\ ,-c osrqTFS7J UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION 10

Z 1200 Sixth Avenue, Suite 900

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Seattle, WA 98101-3140

November 16, 2012

MEMORANDUM

SUBJECT: Intalco BART Technical Review Memo

OFFICE OF

ENVIRONMENTAL ASSESSMENT

FROM:

TO: Steve Body, Environmental Scientist

State and Tribal Air Programs Unit, OAWT

This technical memo summarizes my review and technical analysis regarding the

application of Best Available Retrofit Technology (BART) at the Alcoa Intalco Works

primary aluminum smelter in Ferndale, Washington. As described below, my review

focused primarily on BART for sulfur dioxide [SO 2 ] emitted from the potlines.

Due to the length and complexity of this technical memo, I have structured the document as

a technical report, including a table of contents, list of attachments, and references.

If you have any questions about this memo, please call me at 3-1217.

C: Mark Filippini, Unit Manager, ESU, OEA

Debra Suzuki, Unit Manager, STAPU, OAWT

Juliane Matthews, ORC

Dave Bray, OAWT
 

2 

Table of Contents 

1. Documents Reviewed ............................................................................................................ 4

2. Scope of Review ..................................................................................................................... 5

3. Anode Bake Oven ................................................................................................................... 5

4. Review of SO2 Control Technologies for the Potlines ......................................................... 6

4.1. Dry Sorbent Injection (DSI) or Dry Scrubbing ................................................................. 6

4.2. Semi-Dry FGD or Spray Drying ......................................................................................... 7

4.3. Seawater Scrubbing ........................................................................................................... 8

4.4. Sodium Scrubbing .............................................................................................................. 8

5. Review of Limestone Slurry Forced Oxidation (LSFO) Wet Scrubbing ............................. 9

5.1. Technical Feasibility .......................................................................................................... 9

5.2. Cost Effectiveness ............................................................................................................. 10

5.2.1. Low Bid .......................................................................................................................... 10

5.2.2. Single Scrubbing Tower ............................................................................................... 11

5.2.3. Equipment Life .............................................................................................................. 12

5.2.4. Gypsum Reuse ............................................................................................................... 13

5.2.5. Erection Cost ................................................................................................................. 14

5.2.6. Summary of Cost Effectiveness ................................................................................... 14

5.3. Environmental Impacts of LSFO ..................................................................................... 15

5.3.1. Wastewater ................................................................................................................... 15

5.3.2. Water ............................................................................................................................. 16

5.3.3. Air Quality ..................................................................................................................... 16

5.3.4. Energy ............................................................................................................................ 17

5.3.5. Solid Waste .................................................................................................................... 17
 

3 

Attachments 

Ecology BART Analysis for Intalco ................................................................................. Attachment 1 

Environ BART Analysis for Intalco ................................................................................. Attachment 2 

Hatch Pre-Feasibility Report ............................................................................................ Attachment 3 

40 CFR 51 Appendix Y ......................................................................................................... Attachment 4 

Intalco Primary Call Log – Zach Hedgpeth .................................................................. Attachment 5 

NY SPDES Permit Form NY-2C for Massena-East Smelter .................................... Attachment 6 

Email from Robert Jacobs, NYDEC dated 1/10/12 .................................................. Attachment 7 

NY SPDES Number NY0000132 – Massena-East Smelter ..................................... Attachment 8 

Intalco Wastewater Flow Schematic, June 2011 ....................................................... Attachment 9 

Intalco NPDES Fact Sheet 2007 .....................................................................................Attachment 10 

EPA Region 10 LSFO Cost Effectiveness Analysis ...................................................Attachment 11 

EPA Region 10 LSFO Capital Cost Scaling Summary Table .................................Attachment 12 

EPA Region 10 Market Review for Intalco-Produced Gypsum .........................Attachment 13 

Intalco LSFO Cost Elements Comparison ...................................................................Attachment 14 

EPA Region 10 Intalco Water Demand Memo to File ............................................Attachment 15 
 

4 

1. Documents Reviewed 

This memo describes my technical review of BART as it applies to the Intalco primary 

aluminum smelter. My review necessarily began with the BART analysis for Intalco 

submitted to EPA by the Washington State Department of Ecology1. This document was 

submitted to EPA within Appendix L of the Washington Regional Haze State 

Implementation Plan (SIP), and is available along with supporting information on Ecology’s 

BART website2. This document is also included as Attachment 1 to this memo, and is 

referred to as the “Ecology BART analysis” throughout this memo. 

However, research identified four additional primary technical documents on which 

Ecology’s analysis relied substantially, either directly or indirectly. 

Ecology’s BART analysis was developed primarily based on a BART analysis for Intalco 

prepared by Environ Corporation under contract with the company3. This document is 

included as Attachment 2 to this memo, and is referred to as the “Environ BART analysis” 

throughout this memo. 

The Environ BART analysis contains the BART analyses for the potlines and other emission 

units subject to BART at Intalco. Environ’s technical feasibility and cost evaluation of 

limestone slurry forced oxidation (LSFO) scrubbing for SO2 removal are based in part on a 

pre-feasibility report4 prepared by Hatch under contract with Intalco’s parent company 

Alcoa Corporation. This document is included as Attachment 3 to this memo, and is 

referred to as the “Hatch pre-feasibility report” throughout this memo. 

The Hatch and Environ analyses in turn utilized equipment capital cost quotes from two 

vendor reports commissioned by Alcoa for their smelter in Alcoa, Tennessee. These capital 

cost quote documents are described as the Vendor #1 quote and the Vendor #2 quote in 

this document. I obtained these two vendor documents in order to perform a thorough 

review of the cost analysis. Alcoa submitted these two documents to EPA accompanied by 

a claim that they contained confidential business information (CBI). 

In the Regional Haze SIP, Washington requires all sources subject to BART to follow EPA’s 

BART Guidelines of 40 CFR 51 Appendix Y; see Section 1.1 of the Ecology BART analysis. 

Likewise, I used Appendix Y as the basis for this technical review. A copy of Appendix Y is 

included as Attachment 4 to this document. 

 

1

 Washington State Department of Ecology, “BART Determination Support Document for Alcoa Intalco Works, 

Ferndale, Washington”, dated August 2009, revised February 4, 2010.

2

http://www.ecy.wa.gov/programs/air/globalwarm_RegHaze/BART/BARTInformation.html#Intalco

3

Environ Corporation, “BART Determination for Alcoa Intalco Works, Ferndale, Washington”, dated 

November 2007.

4 Hatch, “Alcoa Primary Metals USA, Pre-Feasibility Report, SO2 Scrubbing for the Intalco Primary Aluminum 

Smelter”, dated November 5, 2007.
 

5 

2. Scope of Review 

I reviewed Ecology’s BART analysis for Intalco in its entirety, but address most components 

in an abbreviated manner or only via summary comment. My review focused on the BART 

determination for sulfur dioxide (SO2) from the potlines for the following reasons: 

1. The pollutants of interest with respect to visibility impacts are particulate matter 

(PM), nitrogen oxides (NOX), and sulfur dioxide (SO2). 

2. SO2 emissions from Intalco significantly impact visibility at Olympic National Park 

and up to six other Class I areas in Washington. 

3. According to the Ecology BART analysis, the potlines are permitted to emit 37,780 

pounds of SO2 per day (6,895 tons per year). 

4. The primary air pollution control system employed by Intalco for control of potline 

emissions consists of dry alumina injection followed by fabric filtration. This level 

of control appears consistent with BART for PM. 

5. As described in the Ecology BART analysis, emissions of NOX from the potlines are 

insignificant since the potlines are electrically heated (versus combustion of fossil 

fuels) and none of the raw materials contain significant quantities of nitrogen. 

6. The potlines are the primary industrial process at the facility and are not equipped 

with active control technology for SO2. Currently the sole air pollution control 

strategy in place to reduce emissions of SO2 from the potlines consists of limits on 

sulfur content in the petroleum coke (3.0 %) and pitch (0.6 %) used in the 

manufacture of the pre-baked anodes. The anodes are consumed in the production 

of aluminum, thereby directly emitting SO2. 

Other than limited discussion of the anode bake oven, the bulk of this memo delineates the 

areas and portions of the BART technical analysis for SO2 emissions from the potlines at the 

Intalco smelter where I disagree with the state and facility analyses. The memo also 

presents my revised cost effectiveness analysis for SO2 from the potlines. I generally agree 

with the Environ and Ecology BART analyses with respect to other pollutants and emission 

units at Intalco. 

3. Anode Bake Oven 

The anode bake oven is the next largest air pollutant emitting process after the potlines. 

The oven has uncontrolled emissions of 181 tons of SO2 per year according to the Environ 

BART analysis. According to the Ecology BART analysis, the oven also emits PM, NOX, 

hydrocarbons, and fluoride, and has a total maximum visibility impact of approximately 

0.053 deciview at Olympic National Park. Environ, in their BART analysis, estimates that 

approximately 40% of this visibility impact is due to SO2 emissions. The oven is fired on 

natural gas and emissions are controlled with a dry alumina scrubber and baghouse similar 

to the potlines. The existing dry scrubber system provides high efficiency emission control 

for PM. In their BART analysis, Ecology rejected low efficiency (~20% reduction) controls 

for NOX based on negligible visibility improvement. 

Analyses examining control of SO2 from the anode bake oven assumed that the exhaust gas 

stream would require a separate scrubber from the one controlling the potlines. Based on 
 

6 

a scaling approach described in the Hatch pre-feasibility report, the Environ BART analysis 

includes estimated cost effectiveness values for a dedicated scrubber to control emissions 

from the anode bake oven. These estimates are based on the vendor quotes for the potline 

LSFO scrubber, and resulted in a cost estimate of $36,400/ton of SO2 removed. 

None of the vendor quotes or subsequent cost analyses estimated the cost of routing the 

anode bake oven exhaust gas stream to a scrubber whose primary purpose was controlling 

SO2 emissions from the potlines. Because of the small visibility impact of SO2 emissions 

from the anode bake oven, I did not pursue further research into this potential control 

option. 

4. Review of SO2 Control Technologies for the Potlines 

The Environ BART analysis examined a total of eight control technologies with respect to 

SO2 emissions from the potlines. Two of these control technologies are dry or semi-dry 

scrubbing technologies while the remaining six are wet scrubbing technologies. These 

control technologies are listed below: 

Dry or Semi-Dry Technologies 

1. Dry Sorbent Injection (DSI) or Dry Scrubbing 

2. Semi-Dry Scrubbing or Spray Drying 

Wet Technologies 

3. Limestone Slurry Natural Oxidation (LSNO) Scrubbing

4. Conventional Wet Lime Scrubbing 

5. Dual Alkali Sodium/Lime Scrubbing (dilute mode) 

6. Seawater Scrubbing 

7. Conventional Sodium Scrubbing 

8. Limestone Slurry Forced Oxidation (LSFO) Scrubbing 

Based on the Hatch, Environ, and Ecology documents, I focused my review on LSFO. This 

technology was selected by Environ and Ecology as the best option among the technically 

feasible wet scrubbing technologies, and vendor cost quotes were available. I agree that 

LSFO is the best option based on my independent research and analysis discussed below 

regarding the other technologies, and based on the considerations discussed in the Environ 

and Ecology BART analyses. I did not conduct further analyses regarding LSNO, 

Conventional Wet Lime Scrubbing, and Dual Alkali Sodium/Lime Scrubbing because I agree 

with Ecology’s determination that these technologies either have clear disadvantages or 

are likely to be more costly than LSFO. I conducted targeted research and analysis on the 

remaining control technologies as described below. 

4.1. Dry Sorbent Injection (DSI) or Dry Scrubbing 

Dry Sorbent Injection (DSI) can be used to remove SO2 from an exhaust stream by 

contacting the exhaust gas with a dry powder alkaline reagent, which is usually calcium or 

sodium based. Under appropriate conditions, SO2 and other acid gasses are adsorbed onto 

the dry reagent particles and react with the reagent to form a solid salt. The particulate 

matter must be removed downstream, usually via a baghouse or electrostatic precipitator. 
 

7 

Dry scrubbing can achieve between 50-90% SO2 removal depending on the reagent used 

and other design factors (EPA, 2003). 

The Ecology BART analysis discusses dry scrubbing on page L-68, and rejects the 

technology as technically infeasible due to the low temperature of the exhaust gas 

downstream of the existing baghouses (≤ 205° F) and the low SO2 concentration (≤ 105 

parts per million by volume, ppmv) in the exhaust gas. Ecology based this determination 

on the Environ BART analysis, which in turn appears to be based on an EPA Fact Sheet, 

establishing 300° F as the minimum required temperature for dry sorbent injection (EPA, 

2003). In addition to literature review which generally supports this finding (EPA, 2000 

and NCSU, 1998), I contacted a vendor of dry scrubbing technology5 who confirmed the 

importance of exhaust gas stream temperature, and stated that their dry scrubbing 

technology could successfully control SO2 emissions for gas stream temperatures down to 

approximately 250-260° F. 

Potential approaches to increasing the gas stream temperature such as fixing duct leaks 

which introduce cold ambient air and/or direct heating of the exhaust stream were not 

discussed in the Environ BART analysis. Using strategies such as these, it may be possible 

to raise the gas stream temperature a sufficient amount (on the order of 50-100° F) to 

make dry scrubbing technically feasible. However, direct heating is likely to require 

significant fuel usage since the volumetric flow rate of exhaust gas from the potlines is on 

the order of 2 million actual cubic feet per minute (acfm). 

Upstream of the existing baghouses, the exhaust gas temperature may be in the 

temperature range that is technically feasible for DSI. However, injection of the alkaline 

reagent would be likely to render the baghouse catch unsuitable for recycling to the 

potlines as is the current practice for reclamation of the alumina and collected fluorides. 

Based on these considerations, I agree with Ecology’s determination that with a flue gas 

temperature of ~205° F, dry scrubbing is technically infeasible for control of SO2 emissions 

from the potlines at Intalco. 

4.2. Semi-Dry FGD or Spray Drying 

Spray drying is similar to dry scrubbing except that the alkaline reagent is sprayed in slurry 

form into the exhaust gas (usually within an absorber chamber) upstream of a particulate 

matter removal device. Spray drying is generally able to achieve higher rates of SO2

removal than dry scrubbing because the moisture on the particles enhances SO2 removal 

(EPA, 2003). The quantity of water that is injected is carefully controlled in order to ensure 

that the exhaust gas stream is dry by the time it reaches the particulate matter control 

device. Because of the need to evaporate the moisture introduced into the exhaust gas, 

spray drying generally requires temperatures higher than those needed for dry scrubbing. 

Based on the temperature requirements, I agree that spray drying is technically infeasible 

for control of SO2 from the potlines at Intalco. 

 

5

 See Attachment 5. September 7, 2011 phone conversation with Don Hug of Allied Environmental. 
 

8 

4.3. Seawater Scrubbing 

Seawater scrubbing is used in Europe for control of SO2 emissions from primary aluminum 

smelters similar to Intalco (Exponent, 2005). As with other wet scrubbing technologies, an 

alkaline solution (in this case seawater) is sprayed into the exhaust gas stream within one 

or more vertical towers. By encouraging contact between the SO2-containing gas stream 

and the slightly alkaline seawater, SO2 is removed from the gas stream via absorption. 

Unlike LSFO and certain other wet scrubbing technologies, seawater scrubbing is a “once 

through” technology where the entire scrubber flow rate must be disposed of as 

wastewater. 

As described on pages L-81 to L-83 in their BART analysis, although technically feasible, 

Ecology eliminates seawater scrubbing from consideration as BART due to water quality 

discharge concerns. Unlike aluminum plants in Europe, wastewater discharge from 

primary aluminum smelters in the U.S. must comply with specific limits on fluorides among 

other pollutants (see 40 CFR 421, Subpart B). The Ecology BART analysis reiterates the 

argument developed in the Environ BART analysis stating that the necessary wastewater 

treatment facilities would not be cost-effective, and would produce a large amount of 

wastewater treatment sludge. Treatment of seawater would produce significantly more 

sludge than freshwater since precipitation of the natural salts would be necessary in order 

to remove target pollutants. 

Besides the concerns noted by Ecology the offshore aquatic area immediately surrounding 

the Intalco smelter has been designated as an environmental aquatic reserve for the 

protection of herring. New saltwater intake structures, which would be necessary for 

seawater scrubbing, are explicitly prohibited on page 54 of the Cherry Point Environmental 

Aquatic Reserve Management Plan (DNR, 2010). 

No cost analysis was conducted for seawater scrubbing. It is likely that the costs associated 

with extending saltwater intake and outfall infrastructure beyond the aquatic reserve and 

associated wastewater treatment and sludge disposal costs would result in the technology 

being deemed cost-prohibitive, but these analyses were not included in either the Ecology 

nor Environ BART analyses. Based on these considerations, I agree that although seawater 

scrubbing is technically feasible, it cannot be considered BART for control of SO2 emissions 

from the potlines at Intalco. 

4.4. Sodium Scrubbing 

Sodium scrubbing is a wet scrubbing technology using scrubber liquor containing a sodium 

reagent. The infrastructure and associated capital costs for a sodium scrubber would be 

similar to that of LSFO, although sodium-based reagents are generally more expensive than 

limestone or lime (NCSU, 1998). Furthermore, based on the wastewater issues 

experienced at the Alcoa Massena-East smelter in New York, a new sodium scrubber for the 

potlines at Intalco may require significant upgrades to the wastewater treatment plant at 

Intalco in order to comply with water quality standards and protect the Cherry Point 

Aquatic Reserve. Accordingly, research suggests that sodium scrubbing would be more 

costly than LSFO. 
 

9 

Research indicates that the Massena-East plant is the only primary aluminum plant in the 

United States that currently operates a sodium scrubber for control of SO2 from potlines. 

The sodium scrubber wastewater bleed stream requiring treatment at Massena-East is 

approximately 32 gallons per minute (gpm)6. This facility has had difficulty meeting its 

wastewater discharge permit limits7 despite having more advanced wastewater treatment 

infrastructure than is currently in place at Intalco8. 

Currently, emissions from the roof vents at Intalco are controlled by a series of small, dilute 

sodium scrubbers using soda ash9. The wastewater bleed stream from the roofline 

scrubbers which requires secondary treatment prior to discharge is approximately 48 

gallons per minute (gpm)10. Secondary treatment at Intalco consists of an equalization 

tank followed by two parallel treatment trains, each including reaction and flocculation 

vessels for chemical treatment. Solids are removed using a clarifier and dewatered before 

disposal at the facility’s onsite landfill11. 

The experience at the Massena-East plant is consistent with information available in the 

literature suggesting that treatment of process wastewater from sodium scrubbers can be 

more difficult due to the high solubility of sodium compounds (APTI, 1998). This 

characteristic of sodium scrubbers is also noted on page 17 of the Environ BART analysis. 

Based on these considerations, although sodium scrubbing is technically feasible for 

control of SO2 emissions from the potlines at Intalco, I consider it likely to be more 

expensive than LSFO. 

5. Review of Limestone Slurry Forced Oxidation (LSFO) Wet Scrubbing 

5.1. Technical Feasibility 

On pages 5-5 and 5-17 of their BART analysis, Environ identifies LSFO as the best choice 

among technically feasible control technologies for SO2 emissions from the potlines. I 

agree with this determination based on evaluation of the Environ BART analysis, as well as 

the Hatch pre-feasibility report and the two quotes from Vendors #1 and #2 cited above. 

All of these consultant reports agree that LSFO achieving an SO2 removal efficiency of 95% 

is technically feasible for the Intalco potlines. Ecology also confirms the determination that 

LSFO is technically feasible on page L-68 of their BART analysis. 

 

6

See Attachment 6. New York State Pollutant Discharge Elimination System (SPDES) Number NY0000132. 

Industrial Application Form NY-2C, Section II Outfall Information. Massena-East Facility, Outfall 01A. Process 

wastewater flow rate = 0.046 million gallons per day (~32 gallons per minute).

7

See Attachment 7. January 10, 2012 email from Robert Jacobs, New York State Department of 

Environmental Conservation. 

8

See Attachment 8. New York SPDES Number NY0000132 for the Massena-East Smelter. Carbon treatment 

is cited for Outfall O1A on page 24 of 28. 

9

See Attachment 5. December 2, 2011 phone conversation with Kathryn Mitchell, Environmental Manager – 

Alcoa Intalco Works. 

10 See Attachment 9. Process and Storm Water Flow Schematic, Intalco Aluminum Corporation, June 2011. 

Flow rate to secondary treatment = 0.07 million gallons per day (~48 gallons per minute). 

11 See Attachment 10. Intalco Fact Sheet for NPDES Permit WA-000295-0, March 15, 2007, page 8. 
 

10 

Ecology eliminated LSFO from consideration as BART based on cost-effectiveness as well as 

secondary environmental impacts, which are detailed below. 

5.2. Cost Effectiveness 

As discussed above, all capital cost estimates for LSFO are based on two site-specific 

vendor quotes for the primary aluminum smelter located in Alcoa, Tennessee. In the Hatch 

pre-feasibility report and the Environ BART analysis, the two capital equipment quotes 

were averaged and scaled from the Tennessee facility to the Intalco operations based on 

differences in limestone consumption, gypsum production, and exhaust gas flow rate. 

These calculations are summarized in Appendix D of the Environ BART analysis. Environ’s 

BART analysis for LSFO to control SO2 emissions from the potlines resulted in a cost 

effectiveness value of $7,500/ton of SO2 removed. 

Ecology made several revisions to the Environ cost effectiveness analysis for LSFO for the 

potlines in their BART analysis, reducing the cost effectiveness value to $6,145/ton. The 

most significant change Ecology discusses is to eliminate the second spray tower which 

was included in the Hatch and Environ documents. This second spray tower provided 

100% scrubbing redundancy. 

As described in this memo and attachments, I am further revising the BART cost 

effectiveness analysis for LSFO to control SO2 emissions from the potlines at Intalco. I 

agree with Ecology that the redundant scrubbing tower is not necessary for the purposes of 

Regional Haze, and I also make several other changes to the analysis, further improving the 

cost effectiveness to an estimated range of $3,875 – $4,363/ton. My detailed cost 

effectiveness analysis is included as Attachment 11 to this memo. In addition to 

eliminating the cost for the redundant absorber, the primary changes made to the analysis 

are: 

• The lower of the two vendor quotes is used rather than the average, 

• The scrubber equipment life is assumed to be 30 years rather than 15, 

• I assume the gypsum by-product is re-used rather than sent to a landfill, and 

• I evaluated the cost using a 40% erection cost factor (per the EPA Control Cost 

Manual), and alternatively an 80% erection cost factor (as used by Environ). 

The following sections include my rationale and basis for the primary changes to the 

Environ cost effectiveness analysis for LSFO on the potlines. 

5.2.1. Low Bid 

As discussed, I obtained copies of the capital equipment quotes from Vendor #1 and 

Vendor #2 for LSFO to be installed on the potlines at the Tennessee smelter. The Environ 

BART analysis averaged these two quotes in applying these capital costs to the Intalco 

potlines. This approach is unacceptable based on the EPA Air Pollution Control Cost 

Manual (EPA, 2002), and is not in accordance with standard contracting procedures. 
 

11 

The Control Cost Manual clearly supports the use of the low bid. Specifically, the manual 

states that “[s]ignificant savings can be had by soliciting multiple quotes”12 and discusses 

the ability to “compare to other bids”13. 

This is in accordance with the standard contracting procedure of selection of the lowest 

responsive bid for equipment or services. The qualifier “responsive” generally serves to 

allow exclusion of bids which are deemed inadequate to satisfy the requirements of the 

project. In this case, both bids were submitted by experienced, reliable equipment 

suppliers and were obviously considered responsive by Hatch and Environ since both 

quotes were utilized in both the Environ BART analysis and the Hatch pre-feasibility report 

for Intalco. 

My cost effectiveness analysis uses the lower of the two capital equipment quotes, scaled 

from the Tennessee smelter to Intalco using the method described in the Hatch prefeasibility report. The specific method used to scale the capital quotes developed for the 

Tennessee smelter to the Intalco smelter is described in section 5 of the Hatch report. This 

scaling approach can be summarized as follows. 

The total capital cost of the LSFO system is broken down into specific components of the air 

pollution control system. For example, the reagent feed system is assumed to account for 

10% of the total capital cost. Each specific component of the capital cost is then scaled 

based on the most relevant operational parameter using a general formula for cost scaling. 

For example, the reagent feed system cost is scaled based on estimated limestone 

consumption. 

In calculating my scaled capital cost, I followed the method described in the Hatch prefeasibility report with the exception that I used the lower of the two bids rather than the 

average. The EPA Region 10 and Environ capital cost scaling calculations are summarized 

in Attachment 12. Scaling the capital costs based on the lower bid rather than the average 

reduced the Intalco capital cost from $80,445,682 to $71,142,440. 

5.2.2. Single Scrubbing Tower 

The Environ BART analysis is based on the assumption of a two absorber (spray tower) 

system, providing 100% redundancy. This approach was taken in order to provide the 

same level of emissions control all the time, including during routine shutdown and 

maintenance of the primary spray tower. Primary aluminum facilities such as Intalco do 

not typically shut down operations periodically (as is usual across industry) since a potline 

is in continuous operation once started-up. 

The Ecology BART analysis reduces the costs significantly by assuming that the LSFO 

system required to be installed on the potlines will have only a single absorber tower. One 

of the vendors provided quotes for both dual tower and single tower LSFO systems, with 

 

12 EPA, 2002. Page 3-38; Chapter 3 – Electrostatic Precipitators; Section 6 – Particulate Matter Controls.

13 EPA, 2002. Page 1-29; Chapter 1 – Selective Non-catalytic Reduction (SNCR); Section 4.2 – NOX Post 

Combustion.
 

12 

the single tower system capital costs being about 28% lower than the dual tower system. 

Installation of LSFO with a single absorber tower would result in some amount of scrubber 

down time during which emissions from the existing dry scrubbers/fabric filters would be 

released uncontrolled for SO2 emissions (as is currently the case all the time).

I agree that this change made by Ecology is appropriate, and consider that the significant 

additional cost incurred by a two tower design to provide 100% redundancy is not an 

appropriate basis for rejecting LSFO as too costly as BART. A single scrubbing tower 

designed to treat the entire potline exhaust gas stream can be expected to achieve 

significant SO2 reductions at a reduced cost. I consider this type of system modification to 

be appropriate in order to develop a cost effective BART control option to protect visibility 

under the Regional Haze Program. 

My analysis incorporates this reduced capital equipment cost as well as reduced SO2

removal based on an estimated two week annual shutdown of the scrubber for necessary 

maintenance. 

5.2.3. Equipment Life 

The Environ BART analysis uses an expected equipment lifetime of 15 years for the LSFO 

system. No basis for the 15 year lifetime is given; the number is listed only as an 

assumption. I disagree that 15 years is an appropriate length of time to use as the 

equipment life14 for LSFO. My cost analysis uses a 30 year lifetime. My basis and rationale 

are described below. 

The expected service life of wet flue gas desulfurization (FGD) systems such as LSFO is 

cited as 30 years in the literature. Specifically, the air pollution control textbook 

“Estimating Costs for Air Pollution Control”

15 cites 30 years as the typical lifetime for FGD 

systems (Vatavuk, 1990). Additionally, an equipment life of 30 years is cited in published 

papers, including a 2002 article in Chemical Engineering & Technology magazine (Warych, 

2002)16 and a published EPA report (Kaplan, 1990). 

The actual life of wet FGD scrubbers installed at coal fired power plants has been 

demonstrated to be 30 years or more for many plants. Industry reports establish scrubber 

longevity near or exceeding 30 years. For example, I examined a public report by the 

Electric Power Research Institute (EPRI) which reviewed the operations of a large number 

of coal fired power plants (EPRI, 2005). Of the plants reviewed in this report, roughly a 

dozen plants which are currently in operation have wet limestone FGD systems that were 

installed in the 1970’s and 1980’s. Examination of the record of FGD systems on coal fired 

power plants is useful due to the established nature of this control device in industry, and 

because the large exhaust gas flow rates from utility boilers are generally comparable to 

those produced by primary aluminum smelters such as Intalco. In fact, the less 

 

14 EPA, 2002. See Chapter 2 – Cost Estimation: Concepts and Methodology; Section 1 – Introduction, 

specifically pages 2-19 through 2-21 for discussion of equipment life. 

15 Vatavuk, 1990. See page 198.

16 Warych, 2002. See pages 427-432. 
 

13 

concentrated pollutant gas stream from an aluminum smelter suggests that the FGD system 

longevity may be enhanced when compared to an FGD scrubber controlling emissions from 

a coal fired boiler due to reduced wear and tear on the scrubber components. 

Based on the literature citations of 30 years as a typical expected FGD life and the actual 

longevity of FGD equipment in industry I consider 30 years to be a reasonable timeframe 

for use as the actual equipment life for LSFO at Intalco. The use of a 30 year life is also 

consistent with other BART determinations made by EPA. See for example the Oklahoma 

BART Federal Implementation Plan (FIP) final rule issued by Region 617. 

5.2.4. Gypsum Reuse 

The Environ BART analysis assumes the gypsum produced as a by-product from LSFO at 

Intalco would be disposed of in a landfill at a cost of $145/ton (about $4 million per year). 

Yet the Environ BART analysis as well as LSFO design information contained within the 

vendor cost quotes indicates that the gypsum produced as a by-product of LSFO would be 

suitable for re-use. 

Region 10 conducted an internal economic analysis to evaluate the potential for beneficial 

reuse of the gypsum by-product from LSFO (Attachment 13). This analysis identified 

several applications for FGD gypsum in addition to market factors which suggest the likely 

presence of a market for the gypsum produced by Intalco. Specifically, the analysis found 

that a significant price differential exists between FGD gypsum and natural (mined) 

gypsum favoring the former. Also, the quantity of FGD gypsum produced by Intalco would 

constitute a very small percentage of the market and is comparable to the quantity likely 

used by area cement plants18. Also, anecdotal evidence indicates that synthetic gypsum 

produced by the LSFO scrubber at the TransAlta coal-fired power plant in Centralia, WA is 

a highly sought after “green” product19. Additionally, with the recently imposed 

requirement that the TransAlta plant cease burning coal in their two boilers in 2020 and 

202520, this local source of synthetic gypsum will no longer be available. This would 

reasonably be expected to positively impact demand for other regional sources of synthetic 

gypsum such as Intalco. 

Furthermore, a cost study for the LSFO scrubber at the Centralia power plant which was 

conducted by Sargent & Lundy (Sargent, 1996) prior to scrubber construction took re-use 

of the gypsum by-product into account and applied a credit of $5/ton to the cost analysis. 

 

17 76 FR 81728, December 28, 2011. 

18 For example, the Ash Grove Cement Plant in Seattle has a maximum production capacity of approximately 

750,000 tons of cement clinker per year (PSCAA, 2004). Gypsum is generally used as an additive to clinker at 

approximately 4-5% by weight (Shreve’s, 1984). At the 5% rate, the Ash Grove Cement Plant in Seattle would 

use about 37,500 tons of gypsum annually when operating at full load. According to Environ, a LSFO scrubber 

at Intalco would produce approximately 27,130 tons of gypsum when operating at full capacity. 

19

“TransAlta and George Pacific Share Win-Win Situation”. Daniel Brunell. Association of Washington 

Business online article. July-August 2004. 

http://www.awb.org/articles/environment/transalta_and_georgia_pacific_share_win_win_situation.htm

20 See Ecology Order No. 6426, 1st Revision, Issued December 13, 2011. Available on Ecology’s website at 

http://www.ecy.wa.gov/programs/air/TransAlta/TransAlta_Revised_BART_CO_12-13-2011.pdf
 

14 

Sargent & Lundy also estimate that disposal of the FGD gypsum would cost only $6/ton. 

Although these costs are presented in 1996 dollars, a large discrepancy exists between the 

Sargent & Lundy analysis and the $145/ton disposal cost used in the Environ BART 

analysis. 

Based on the design specification establishing that the gypsum by-product would be 

suitable for commercial reuse, the evidence suggesting a likely market for the gypsum, and 

the considerable financial incentive that would exist for Intalco to sell or even give away 

the FGD gypsum rather than landfill it, I do not agree that it is reasonable to assume that 

the gypsum from the LSFO process will be disposed of in a landfill. Furthermore, it appears 

that the $145/ton disposal cost used in the Environ BART analysis likely overstates the 

disposal costs. 

My cost effectiveness analysis therefore eliminates the gypsum disposal costs and assumes 

that Intalco gives the gypsum away free on board21 at the facility in Ferndale. Any proceeds 

from the sale of the gypsum would further improve the LSFO scrubber cost effectiveness. 

5.2.5. Erection Cost 

The Environ BART analysis doubles the cost factor used in the EPA Control Cost Manual to 

estimate the costs of erecting the control equipment. Specifically, the EPA Control Cost 

Manual estimates the erection cost as 40% of the purchased equipment cost (PEC). 

Environ’s BART analysis doubles this factor to 80% of the PEC. The Environ BART analysis 

justifies this increase only by referring to “retrofit of the existing plant and onsite 

fabrication”. In my opinion, inadequate basis is provided in the Environ BART analysis for 

this cost increase. 

As discussed in the EPA Control Cost Manual, it is reasonable to consider additional costs 

which are determined to be necessary for retrofit projects. However, since no basis for the 

doubled erection cost was provided, my cost effectiveness analysis presents costs with and 

without this additional cost in order to illustrate the impact this apparently arbitrary and 

unsupported additional cost has on cost effectiveness. If the EPA Control Cost methodology 

is used, my estimate of the cost effectiveness of LSFO falls from $4,363/ton to $3,875/ton. 

5.2.6. Summary of Cost Effectiveness 

A table describing the differences between the Environ and the EPA Region 10 LSFO cost 

analyses in more detail is included as Attachment 14. The following summarizes the 

Environ and EPA LSFO cost analyses. 

Environ EPA Region 10

Low

EPA Region 10

High

Capital Cost (millions) $235 $128 $152

Annual O&M Costs (millions) $21 $14 $14

Cost Effectiveness ($/ton) $7,500 $3,875 $4,363

 

21 Free on Board, defined here where the buyer pays for all loading, transportation, and unloading costs.
 

15 

5.3. Environmental Impacts of LSFO 

Although operation of an LSFO scrubber on the Intalco potlines has the potential to reduce 

SO2 emissions by over 6,000 tons per year, the scrubber would result in collateral energy 

and environmental impacts. A summarized discussion of these impacts is included below. 

5.3.1. Wastewater 

According to the Environ BART analysis, “only a very small purge or blowdown stream is 

required”22 for the LSFO system contemplated for control of SO2 from the Intalco potlines. 

Review of the vendor reports obtained by Region 10 from Alcoa corroborates this 

statement, indicating that preliminary design of the LSFO system included either a 

wastewater purge flow rate of a few gallons per minute, or no purge flow rate at all. 

Further, Section 3.2 of the Hatch pre-feasibility report includes a detailed description of the 

liquid stream dispositions, and states that "the gypsum is left with 15 percent moisture 

which prevents the need for a liquid purge stream otherwise needed to purge impurities 

from the process". 

I also conducted additional investigations to further examine whether LSFO is likely to 

result in significant negative water quality impacts. My additional work on this subject 

included research to: 

1. Better understand the ability of Intalco’s existing wastewater treatment 

infrastructure to handle the projected additional wastewater flow rate (if any) from 

a new LSFO scrubber, and 

2. Explore the implications of the Washington Department of Natural Resources 

(DNR) Cherry Point Aquatic Reserve Management Plan (DNR, 2010). 

In order to adequately understand the potential water quality implications of a new LSFO 

scrubber on the potlines at Intalco, I consulted with wastewater engineering staff within 

EPA Region 10. I provided our wastewater engineer with the specific information on the 

projected LSFO wastewater purge stream contained in the CBI vendor documents in 

addition to publicly available information on Intalco’s current wastewater effluent streams 

and treatment infrastructure. Specifically, this information included the preliminary design 

purge flow rate of not more than a few gallons per minute (or no flow at all), and the 

detailed information regarding the existing wastewater quantity and quality as well as 

existing treatment infrastructure at the Intalco smelter. The detailed information 

regarding the current wastewater streams and treatment infrastructure is contained in the 

NPDES materials included as Attachments 9 and 10. This internal review resulted in the 

opinion that the very small projected new wastewater purge stream from LSFO is unlikely 

to require significant upgrades to the existing wastewater treatment infrastructure at 

Intalco. However, it is likely that modification to the facility NPDES23 permit would be 

required if the scrubber did produce a new, small wastewater purge stream. 

The majority of the near shore aquatic lands adjacent to the Intalco smelter are included in 

an aquatic lands reserve established by the State of Washington (DNR, 2010). This aquatic 

 

22 See Attachment 2, page 5-5. 

23 National Pollutant Discharge Elimination System
 

16 

land is protected by a management plan which would likely subject modified NPDES permit 

approvals to requirements beyond those otherwise applicable such as compliance with 

water quality standards. Review of the management plan as well as discussions with staff 

at the Washington DNR24 and Ecology25 who implement the plan indicate that the most 

likely additional requirements would consist of a series of scientific studies described in 

the management plan. According to DNR and Ecology staff familiar with the topic, an initial 

round of these studies has been completed at a cost of approximately $235,000. This cost 

included method development work so that future iterations of the studies may cost 

substantially less. State staff estimated that if a second round of these studies were 

required for a revised NPDES permit at Intalco, they could be completed in about one year. 

Based on the above information, my cost analysis for LSFO includes an additional $235,000 

in first year costs to cover these scientific studies. 

5.3.2. Water 

According to the Environ BART analysis, a new LSFO scrubber on the Intalco potlines 

would use an estimated 182.5 million gallons of fresh water per year or approximately 0.5 

million gallons per day (MGD). In their BART analysis, Environ states that this 9% increase 

over current usage would “significantly impact the community infrastructure”26. On page 

L-79 of their BART analysis, Ecology discusses comments received from Intalco explaining 

that Intalco has relinquished a portion of their historic water rights, making it difficult to 

obtain the water rights for an LSFO scrubber. 

In order to verify the facility and consultant claims regarding the difficulty of obtaining 

water for an LSFO scrubber, I contacted the Whatcom County Public Utility District (PUD), 

which supplies water to Intalco. Contrary to claims by Environ and Intalco, the PUD 

General Manager Stephan Jilk stated that Whatcom County PUD would have no difficulty 

supplying the necessary additional 0.5 MGD of fresh water required by an LSFO scrubber. 

Mr. Jilk also provided more accurate cost information based on the current fee schedule 

used by the PUD. I have included these revised cost figures in my cost effectiveness 

analysis (see Attachment 11). 

My conversation with the General Manager of the Whatcom County PUD is documented in a 

memo to the project file and is included as Attachment 15. 

5.3.3. Air Quality 

Operation of LSFO would increase particulate matter emissions by an estimated 200-300 

tons per year due to solids in the mist droplets that are not removed by the scrubber mist 

eliminators. The precise additional PM emissions will depend on the efficiency of the mist 

eliminators on the scrubber at removing entrained droplets from the exhaust stream. 

 

24 See Attachment 5. November 16, 18, and 22, 2011 phone conversations with Kyle Murphy, Cherry Point 

Aquatic Reserve staff contact – Washington State Department of Natural Resources. 

25 See Attachment 5. November 22, 2011 phone conversation with Randy Marshall, Washington State 

Department of Ecology. 

26 See Attachment 2, page 5-22.
 

17 

Operation of the scrubber would also increase emissions of greenhouse gases from the 

plant by an estimated 17,597 tons/year carbon dioxide equivalent (CO2e), according to the 

Environ BART analysis. 

5.3.4. Energy 

The project would require approximately 68,824,000 kW-hr of electricity per year, or 7.4 

MW. This equates to an increase of about 1.6% from plant maximum power usage of 450 

megawatts27 (Herald, 2011). 

5.3.5. Solid Waste 

The project is projected to produce approximately 27,130 tons of commercial grade 

gypsum annually, which would require disposal if not re-used. As discussed above, I 

consider it reasonable to assume this commercial grade by-product would be reused. 

 

27 365 MW consumption at 80% capacity  ~450 MW at 100% capacity. 
 

18 

References 

APTI, 1998. Scrubber Systems Operation Review Self Instructional Manual, Air Pollution 

Training Institute (APTI) Course SI:412C, Second Edition – Lesson 9: Flue Gas Desulfurization 

(Acid Gas Removal) Systems. Gerald T. Joseph, et al. Industrial Extension Service, College of 

Engineering, North Carolina State University. 1998. Developed under EPA Cooperative 

Agreement CT-902765. 

DNR, 2010. Cherry Point Environmental Aquatic Reserve Management Plan. Washington 

Department of Natural Resources. November 2010. 

http://www.dnr.wa.gov/Publications/aqr_cp_mgmt_plan_2010.pdf

EPA, 2000. Srivistava Ravi K. Controlling SO2 Emissions: A Review of Technologies. US 

Environmental Protection Agency, Office of Research and Development. EPA/600/R00/093. 

EPA, 2002. EPA Air Pollution Control Cost Manual, Sixth Edition. US Environmental 

Protection Agency, Office of Air Quality Planning and Standards. EPA/452/B-02-001. 

http://www.epa.gov/ttn/catc/dir1/c_allchs.pdf

EPA, 2003. Air Pollution Control Technology Fact Sheet: Flue Gas Desulfurization – Wet, 

Spray-Dry and Dry Scrubbers. US Environmental Protection Agency, CICA. EPA-452/F-03-

034. http://www.epa.gov/ttn/catc/dir1/ffdg.pdf

EPRI, 2005. Flue Gas Desulfurization Systems: Component Material Performance & Welding. 

Electric Power Research Institute (EPRI), December 2005. 

Exponent, 2005. Ecological Risk Assessment for Use of Wet Scrubbers at Alcoa Fjarðaál 

Aluminum Plant in Reyðarfjörður, Fjarðabyggð, Iceland. Exponent. September 2005. 

Herald, 2011. Stark, John. Intalco adding 60 jobs, restarting idled smelting capacity.

Bellingham Herald. January 8, 2011. 

http://www.bellinghamherald.com/2011/01/07/1804810/alcoa-to-restart-intalco-2-

other.html

Kaplan, 1990. Retrofit Costs of SO2 and NOX Control at 200 U.S. Coal-Fired Power Plants. 

Kaplan, et al. Presented at the 1990 Pittsburgh Coal Conference, September 11, 1990. 

NCSU, 1998. Scrubber Systems Operation Review: Self Instructional Manual, APTI Course 

SI:412C, Second Edition. Gerald T. Joseph and David S. Beachler. Industrial Extension 

Service, College of Engineering, North Carolina State University. 1998. 
 

19 

PSCAA, 2004. Air Operating Permit and Statement of Basis for Ash Grove Cement Company, 

Inc. – Seattle, WA. Puget Sound Clean Air Agency. Air Operating Permit Issued May 15, 

2004. 

Air Operating Permit 

http://www.pscleanair.org/announce/permits/issued/11339-faop.pdf

Statement of Basis 

http://www.pscleanair.org/announce/permits/issued/11339-fsob.pdf

Sargent, 1996. Cost Study for a 1,400 MW Flue Gas Desulfurization Unit, Centralia Units 1 & 

2. Sargent & Lundy for Pacificorp. October, 1996. 

Shreve’s, 1984. Shreve’s Chemical Process Industries, 5th Edition. George T. Austin. 

McGraw-Hill. 1984. ISBN 0-07-066167-7. 

Vatavuk, 1990. Estimating Costs for Air Pollution Control . William M. Vatavuk. Lewis 

Publishers. 1990. ISBN 0-87371-142-4. 

Warych, 2002. Optimum Values of Process Parameters of the 'Wet Limestone Flue Gas 

Desulfurization System'. J. Warych and M. Szymanowski. Chemical Engineering & 

Technology, v. 25, 2002. 
BART DETERMINATION 

SUPPORT DOCUMENT FOR 

ALCOA INTALCO WORKS 

FERNDALE, WASHINGTON 

Prepared by 

Washington State Department of Ecology 

Air Quality Program 

August 2009 

Revised February 4, 2010 

Final December 2010 L - 60
TABLE OF CONTENTS 

EXECUTIVE SUMMARY ........................................................................................................... iii

1. INTRODUCTION ................................................................................................................... 1

1.1 The BART Program and Analysis Process ...................................................................... 1

1.2 The Alcoa Intalco Plant .................................................................................................... 2

1.3 BART-Eligible Units at Intalco ........................................................................................ 2

1.3.1 Existing Potline Emissions Control .......................................................................... 3

1.3.2 Existing Anode Bake Furnace Emissions Control .................................................... 3

1.3.3 Existing Aluminum Holding Furnace Emissions Control ........................................ 4

1.3.4 Existing Controls for Material Handling and Transfer Operations, Other Natural 

Gas Combustion, and Other Small Miscellaneous Sources ...................................... 4

2. BART TECHNOLOGY ANALYSIS ..................................................................................... 4

2.1 Potline Control Options .................................................................................................... 4

2.1.1 SO2 Control Options ................................................................................................. 4

2.1.2 PM Control Options .................................................................................................. 8

2.1.3 NOX Control Options ................................................................................................ 9

2.1.4 Intalco’s BART Proposal for the Potlines ................................................................ 9

2.2 Anode Bake Furnace Control Options ........................................................................... 10

2.2.1 SO2 Control Options ............................................................................................... 10

2.2.2 PM Control Options ................................................................................................ 10

2.2.3 NOX Control Options .............................................................................................. 11

2.2.4 Intalco’s BART Proposal for the Anode Bake Furnace .......................................... 12

2.3 Aluminum Holding Furnaces ......................................................................................... 12

2.3.1 Aluminum Holding Furnaces Control Options ....................................................... 12

2.3.2 Intalco’s BART Proposal for the Aluminum Holding Furnaces ............................ 12

2.4 Material Handling and Transfer Operations ................................................................... 13

2.4.1 Material Handling and Transfer Operations and Other Miscellaneous Operations 

Control Options ....................................................................................................... 13

2.4.2 Intalco’s BART Proposal for the Material Handling and Transfer Operations ...... 13

3. VISIBILITY IMPACTS AND DEGREE OF IMPROVEMENT ......................................... 13

4. ECOLOGY’S BART DETERMINATION ........................................................................... 14

Appendix A. Description of Available SO2 Potline Control Options .......................................... 18

Appendix B. LSFO Scrubber Control Scenarios–Emissions and Impacts .................................. 22

Appendix C. Acronyms/Abbreviations ........................................................................................ 24

Final December 2010 L - 61
EXECUTIVE SUMMARY 

The Best Available Retrofit Technology (BART) program is part of the larger effort under the 

federal Clean Air Act Amendments of 1977 to eliminate human-caused visibility impairment in 

all mandatory federal Class I areas. Sources that are required to comply with the BART 

requirements are those sources that: 

1. Fall within 26 specified industrial source categories. 

2. Commenced operation or completed permitting between August 7, 1962 and 

August 7, 1977. 

3. Have the potential to emit more than 250 tons/year of one or more visibility impairing 

compounds. 

4. Cause or contribute to visibility impairment within at least one mandatory federal Class I 

area. 

 

The Alcoa Intalco Works (Intalco) is a primary aluminum smelter facility utilizing the prebake 

process. The smelter is located on Cherry Point near Ferndale, Washington. The aluminum 

smelting process produces emissions of particulate matter (PM), fluorides, sulfur dioxide (SO2), 

carbon monoxide (CO), nitrogen oxides (NOX), and hydrocarbons. The pollutants considered to 

be visibility impairing are PM, SO2, and NOX. 

Aluminum smelters such as the Intalco facility are one of the 26 listed BART source categories. 

The Intalco plant was constructed in 1965 and has the potential to emit more than 250 tons/year 

of PM and SO2. Most of the plant’s emission units are BART-eligible. Intalco’s major sources 

of visibility impairing pollutants are three potlines and an anode bake furnace. 

Modeling of visibility impairment was done following the Oregon/Idaho/Washington/EPARegion 10 BART modeling protocol.1

 Modeled visibility impacts of baseline emissions show 

impacts on the 8th highest day in any year (the 98th percentile value) to be greater than 0.5 

deciviews (dv) at seven Class 1 areas. The highest impact was 2.36 dv on Olympic National 

Park. Modeling showed that SO2 emissions from the existing dry alumina/baghouse potline 

emission control system created 94 percent of the facility’s total visibility impact. 

Intalco prepared a BART technical analysis using Washington State’s BART Guidance.2

The Washington State Department of Ecology (Ecology) determined that the current level of 

emissions control is BART for the applicable units at the Alcoa Intalco Works primary 

aluminum smelter facility. The potlines and anode bake furnace are currently well controlled for 

particulate emissions. A wet scrubber on each source would be required to control SO2

emissions. Modeling indicated that addition of a wet scrubber system on the potlines could 

reduce the visibility impact on Olympic National Park by over a deciview. However, the potline 

scrubber system’s estimated $7,500 cost per ton of SO2 removed was determined to be excessive. 

 

1

 Modeling protocol available at http://www.deq.state.or.us/aq/haze/docs/bartprotocol.pdf. 2

 “Best Available Retrofit Technology Determinations Under the Federal Regional Haze Rule,” Washington State 

Department of Ecology, June 12, 2007. 

Final December 2010 L - 62
iv 

Ecology also determined that the wet scrubber would have an excessive capital cost of $234.5 

million and unacceptable impacts on solid waste generation, electrical power use, and water 

consumption. Ecology determined that a scrubber on the anode bake furnace would have an 

excessive $36,400 cost per ton of SO2 removed. 

Final December 2010 L - 63
March 3, 2009, Revised February 4, 2010 

 

 

1. INTRODUCTION 

1.1 The BART Program and Analysis Process 

The federal Clean Air Act Amendments of 1977 (CAA) established a national goal of 

eliminating man-made visibility impairment in all mandatory federal Class I areas. The Act 

requires certain sources to utilize Best Available Retrofit Technology (BART) to reduce 

visibility impairment as part of the overall plan to achieve that goal. 

Requirements for the BART program and analysis process are given in 40 CFR 51, Subpart P 

and Appendix Y to Part 51.3

 Sources are “BART-eligible” if they: 

1. Fall within 26 specified industrial source categories. 

2. Commenced operation or completed permitting between August 7, 1962 and 

August 7, 1977. 

3. Have the potential to emit more than 250 tons/year of one or more visibility impairing 

compounds including sulfur dioxide (SO2), nitrogen oxides (NOX), particulate matter 

(PM), and volatile organic compounds (VOCs). 

Emission units that meet the source category, age, and potential to emit criteria must also make 

the facility “cause or contribute” to visibility impairment within at least one mandatory federal 

Class I area for a “BART-eligible facility” to be “subject to BART.” Ecology has adopted the 

“cause and contribute” criteria that the United States Environmental Protection Agency (EPA) 

suggested in its guideline. BART-eligible units at a source cause visibility impairment if their 

modeled visibility impairment is at least 1.0 deciview (dv). Similarly the criterion for 

contributing to impairment means that the source causes a modeled visibility change of 0.5 dv or 

more. 

The BART analysis protocol in Appendix Y to Part 51, Sections III–V uses a 5-step analysis to 

determine BART for SO2, NOX, and PM. The five steps are: 

Step 1 – Identify all available retrofit control technologies. 

Step 2 – Eliminate technically infeasible control technologies. 

Step 3 – Evaluate the control effectiveness of remaining control technologies. 

Step 4 – Evaluate impacts and document the results. 

Step 5 – Evaluate visibility impacts. 

Ecology requires a facility that is “subject to BART” to prepare a BART technical analysis 

report and submit it to Ecology. Ecology then evaluates the report and makes a BART 

determination decision. This decision is then issued to the source owner as an enforceable 

Order, and included in the state’s Regional Haze State Implementation Plan (SIP). 

3

 Appendix Y to 40 CFR 51–Guidelines for BART Determinations Under the Regional Haze Rule. 

Final December 2010 L - 64
March 3, 2009, Revised February 4, 2010 

 

As allowed by the EPA BART guidance, Ecology has chosen to consider all five factors in its 

BART determinations. To be selected as BART, a control has to be available, technically 

feasible, cost effective, provide a visibility benefit, and have a minimal potential for adverse nonair quality impacts. Normally, the potential visibility improvement from a particular control 

technology is only one of the factors weighed for determining whether a control constitutes 

BART. However, if two available and feasible controls are essentially equivalent in cost 

effectiveness and non-air quality impacts, visibility improvement becomes the deciding factor for 

the determination of BART. 

1.2 The Alcoa Intalco Plant 

Alcoa Intalco Works (Intalco) is a primary aluminum smelter facility located in Ferndale, 

Washington, near Cherry Point along the Strait of Georgia. The facility produces primary 

aluminum metal by the Hall-Heroult reduction process. It was originally constructed in 1965, 

and began operation in 1966. Intalco is a Title V source operating under Air Operating Permit 

No. 000295-0. Primary aluminum ore reduction plants are one of the 26 BART-eligible source 

categories. Intalco submitted a BART Determination Report to the Washington State 

Department of Ecology (Ecology) on December 4, 2007 as required by Order #5070. 

1.3 BART-Eligible Units at Intalco 

A review of the Intalco emission sources found that: 

1. All of the plant’s individual emission units except for one remelt furnace are BARTeligible by construction date. 

2. The individual emission units in total have a potential to emit greater than or equal to 

250 tons/year of both sulfur dioxide (SO2) and particulate matter (PM). 

3. A baseline Class I area visibility impact analysis of 2003-2005 emissions using the 

CALPUFF model indicated impacts for the entire facility exceeded the 0.5 deciview (dv) 

contribution threshold in at least one Class I area. This confirmed that Intalco was 

subject to BART, and was required to prepare a BART Determination. 

Intalco’s primary aluminum reduction operations include three potlines, an electrode 

manufacturing operation consisting of a paste production operation and a green anode baking 

furnace, and miscellaneous material handling operations. These units were placed into six 

groups: 

1. Potlines (3) 

2. Anode bake furnace (1) 

3. Aluminum holding furnaces (12) 

4. Various material handling and transfer operations 

5. Combustion sources (natural gas, diesel, propane) 

6. Other small miscellaneous sources 

Final December 2010 L - 65
March 3, 2009, Revised February 4, 2010 

 

1.3.1 Existing Potline Emissions Control 

The potline operation manufactures metallic aluminum by the electrolytic reduction of alumina 

in the side-worked prebake cells. Direct electrical current passes between the anodes and the 

carbon cathode that lines the cell walls. This current electrolytically reduces the alumina to 

metallic aluminum and oxygen. Molten aluminum is deposited and accumulates over time at the 

cathode beneath a layer of molten cryolite bath. Periodically the molten aluminum is siphoned 

from beneath the cryolite bath and processed to achieve specific metal properties or is retained as 

pure aluminum. The produced aluminum is solidified into intermediate or final products. 

The major pollutants emitted from the cells are PM, hydrogen fluoride, SO2, and carbon 

monoxide. PM includes particulate fluoride and alumina. SO2 comes from the sulfur in the 

petroleum coke and pitch components used to make the anodes that are consumed by the process. 

NOX emissions are minimal since there is no external fuel or combustion zone and there are no 

large sources of nitrogen in the raw materials. 

The potlines at Intalco consist of six potroom groups of electrolytic reduction cells connected in 

series that produce molten aluminum. There are two potroom groups per potline. Each potroom 

is comprised of 120 reduction cells (or pots) with 18 anodes per cell. All pots at Intalco are 

hooded to control emissions. Emissions captured by the hoods are drawn through one of six 

primary control systems. Each primary control system consists of a dry alumina injection system 

followed by a baghouse for the control of PM and fluoride emissions. The six primary control 

systems are located in the courtyards between the potrooms. The system at Intalco is large, 

treating approximately 1,815,000 acfm of 180°F exhaust gases. This primary PM control system 

has an efficiency of about 97.7 percent. 

A small fraction of the pot emissions escape capture by the hoods and are released inside the 

potrooms. These secondary emissions are drawn through a secondary control system which 

consists of a series of 159 wet roof scrubbers that control PM and fluoride emissions. PM 

control efficiency for this secondary system is approximately 82 percent. 

1.3.2 Existing Anode Bake Furnace Emissions Control 

Anodes are manufactured in an ancillary on-site anode plant. Purchased calcined petroleum coke 

and anode butt material is crushed and sized, mixed together with pitch, and formed into blocks 

called “green anodes.” The green anodes are then cooled prior to being baked in the anode bake 

furnace. Only after the anodes have been baked can they be used in the potlines. 

The anode bake furnace structure is a series of interconnected refractory flues connected to side 

main exhaust manifolds. The furnace is fueled with natural gas. Exhaust gases are routed so that 

flue gases preheat the next section of the furnace to be fired. Flue gases from the anode bake 

furnace contain PM, hydrogen fluoride, SO2, NOX, carbon monoxide, and hydrocarbons. 

The bake furnace emissions are controlled by an alumina dry scrubber which is similar to the 

ones used for the potline primary control system. The bake oven gas stream is cooled by a water 

Final December 2010 L - 66
March 3, 2009, Revised February 4, 2010 

 

spray to reduce the inlet temperature before it enters the scrubber. Fresh and recycled alumina 

are injected into the gas stream, gaseous fluoride and polycyclic organic matter (POM) are 

adsorbed onto the alumina surface, and fabric filters on top of the reactor compartments collect 

entrained particulate matter present in the gas stream. The control system for the anode bake 

furnace treats approximately 216,000 acfm of 205°F exhaust gases. The fabric filters reduce PM 

emissions by as much as 99 percent. 

1.3.3 Existing Aluminum Holding Furnace Emissions Control 

The 12 holding furnaces at Intalco vary in size. They are heated by natural gas burners. The 

largest of these furnaces has a natural gas rated burner rated at 22 MMBtu/hr. There are no 

emission controls associated with the aluminum furnaces at Intalco. Emissions come from 

combustion of natural gas in the burners and the activities associated with treating molten metal 

while being processed in the furnaces. 

1.3.4 Existing Controls for Material Handling and Transfer Operations, Other 

Natural Gas Combustion, and Other Small Miscellaneous Sources 

The remaining emission units are various material handling and transfer operations, natural gas, 

diesel, and propane combustion, and other small miscellaneous sources that support the potlines, 

anode bake furnace and holding furnace operations. Aside from the natural gas combustion 

products, emissions from most of the support operations consist of relatively small amounts of 

PM that are controlled by fabric filter-type control devices. Fabric filters effectively remove 

about 99 percent of particulate emissions. 

Natural gas consumption is mostly in the previously discussed anode bake furnace and aluminum 

holding furnaces. The balance comes from burners in the paste plant. Propane is used in 

forklifts. There are five small auxiliary diesel generators. 

2. BART TECHNOLOGY ANALYSIS 

The Intalco BART technology analysis was based on the 5-step process defined in BART 

guidance and listed in Section 1.1 of this report. Intalco’s analysis included a review of available 

and technically feasible retrofit technologies (Steps 1 and 2), determination of control 

effectiveness for feasible options (Step 3), evaluation of cost and secondary impacts for feasible 

alternatives (Step 4), and analysis of impacts and visibility improvements (Step 5). The analysis 

looked at controls for SO2, PM, and NOX from each category of emission units: the potlines, 

anode bake furnace, aluminum holding furnaces, handling and transfer operations, combustion 

sources, and other small sources. 

2.1 Potline Control Options 

2.1.1 SO2 Control Options 

Final December 2010 L - 67
March 3, 2009, Revised February 4, 2010 

 

Alcoa evaluated eight different SO2 add-on control options along with pollution prevention as 

having potential application for potline SO2 emission control. Six of the control options use wet 

scrubbing and two use dry scrubbing technology. A description of each technology is found in 

Appendix A. 

Wet Scrubbing Technologies

• Limestone slurry scrubbing with forced oxidation (LSFO) 

• Limestone slurry scrubbing with natural oxidation (LSNO) 

• Conventional lime wet scrubbing 

• Seawater scrubbing 

• Dual alkali sodium/lime scrubbing (dilute mode) 

• Conventional sodium scrubbing 

Dry Scrubbing Technologies 

• Dry sorbent injection 

• Semi-dry scrubbing (spray dryer) 

Limestone Slurry Forced Oxidation (LSFO) was determined to be a technically feasible wet 

scrubbing retrofit control option for the potroom reactors even though it is not ideally suited for 

scrubbing SO2 concentrations that are less than or equal to 105 ppm. LSFO was also selected to 

be the best choice of the wet scrubbing technologies. 

Dry sorbent injection downstream of the potline reactor fabric filters is not technically feasible 

because of the low temperatures (less than or equal to 205°F) and low SO2 concentrations (less 

than or equal to 105 ppm). Spray dry scrubbing downstream of the potline reactors fabric filters 

is not technically feasible because of the low temperatures (less than or equal to 205°F) and low 

SO2 concentrations (less than or equal to 105 ppm). 

Pollution Prevention

The guidelines for BART determinations under the Regional Haze Rule recommend 

consideration of pollution prevention options in addition to add-on controls. The primary 

opportunity for pollution prevention in the smelting process to minimize SO2 emissions is 

through controlling the sulfur content in the incoming petroleum coke used to make the anodes. 

Intalco’s Title V operating permit currently has a number of operational limits that cap allowable 

emissions of SO2 from the facility, including a net potline aluminum production limit of 307,000 

tons/year; a daily potline SO2 limit of 37,780 lb/day; limits on sulfur in coke and pitch at 3.0 

percent and 0.6 percent, respectively; and a carbon consumption limit of 0.425 pounds of carbon 

per pound of aluminum produced. 

The current levels of sulfur in petroleum coke used by other aluminum smelters was evaluated to 

determine whether a pollution prevention option using lower sulfur content coke would be a 

Final December 2010 L - 68
March 3, 2009, Revised February 4, 2010 

 

feasible BART option for Intalco. This analysis indicated that some smelters currently utilize 

coke with sulfur contents as low as two percent. An analysis was also done to determine whether 

coke with sulfur levels below three percent can be anticipated to be available into the future. The 

primary conclusions from this analysis indicate that: 

• There will be a continuing increase in the sulfur content of available coke. Low sulfur 

crude oil supplies are becoming less available and more expensive for petroleum 

refineries. In the future, refineries with coking capacity are expected to minimize their 

raw material costs by using more of the higher sulfur crude oils and oil sands that are less 

costly. 

• As oil fields age, the sulfur content of the crude oil is known to increase and the crude oil 

in the fields becomes more viscous and harder to extract. This effect is expected to 

increase the sulfur content of the petroleum materials available to produce anode grade 

coke. 

• Coke is a relatively small, low revenue component of a refinery’s product profile. It is a 

low value product made from the thick, tar-like refinery wastes left over after all of the 

more valuable components have been removed from the petroleum crude. The aluminum 

industry has little influence in controlling the quantity, quality, and price of the coke 

produced by refineries. 

• Global primary aluminum production is expected to grow, resulting in a commensurate 

growth in demand for anode grade coke. Growth in aluminum production will continue 

to outpace the growth in coke production. 

• Coke providers are blending imported, high cost, lower sulfur coke with domestically 

sourced coke in attempts to meet the current specification requirements for coke. 

• Removal or reduction of the sulfur content of the coke once it has been received is not 

feasible. 

Feasible SO2 Control Options from RBLC Database 

The data in the USEPA’s RACT/BACT/LAER (RBLC) database supports the approach of 

limiting raw material sulfur content as a control option for the potlines and the anode bake 

furnace. Many facilities have limited sulfur content in coke to limit SO2 emissions. Two 

facilities have limits of three percent sulfur content in coke and one has a 2.95 percent sulfur 

content limit. One facility is shown in the RBLC to have a wet scrubber to control SO2

emissions;4

 however, an investigation revealed that the wet scrubber was not required as part of 

a best available control technology (BACT) determination and that the facility currently does not 

operate a wet scrubber to control SO2 emissions. That facility’s current Title V permit for 

“Potline 5” limits coke sulfur content to three percent, coal tar pitch sulfur to 0.8 percent, potline 

SO2 emissions to 364.52 lb/hr from the primary emissions control unit, 7.44 lb/hr from the roof 

 

4

 RBLC ID ky-0070 for NSA–A division of Southwire Company on Potline 5 now Century Aluminum of Kentucky, 

LLC, Kentucky Title V Permit #V-01-019. 

Final December 2010 L - 69
March 3, 2009, Revised February 4, 2010 

 

scrubbers, and 49.356 lb/ton of aluminum produced. Alcoa Intalco has a current limit of 44.8 lb 

SO2 emitted per ton of aluminum produced. 

Cost and Other Impacts of Feasible SO2 Potline Controls 

Wet scrubber costs for Intalco were estimated based on cost quotes received by Alcoa from two 

flue gas desulphurization equipment vendors. The cost quotes were originally provided as part 

of the BART analysis for Alcoa’s Tennessee Operations in Alcoa, TN. Both vendors provided 

cost proposals for wet scrubbing systems based on LSFO scrubbers. Lime or sodium based 

scrubbers could also be used for potlines, but lime and sodium are less desirable reagents 

considering that these reagents are much more expensive. An advantage of the limestone forced 

oxidation process is that the spent slurry is oxidized to gypsum, which dewaters more efficiently, 

resulting in less waste materials requiring disposal. An LFSO scrubber was determined to be the 

most appropriate control device for the cost analysis. 

Neither of the two vendors provided a comprehensive installed cost estimate. Both preliminary 

designs were based on a central scrubbing center as the least cost approach, where exhaust from 

all dry scrubbing systems would be ducted to a centralized scrubbing system. Both design 

estimates were based on systems that would provide 100 percent availability of emissions control 

on each day of the year, given that potlines cannot be easily shutdown and restarted for control 

system outages. To achieve this 100 percent availability, the proposed designs includes two 

scrubber towers, one to be active, and one to be held in reserve. 

The capital and total annualized costs for a potline wet scrubber system as proposed was $234.5 

million and 46.8 million per year, respectively. The wet scrubber cost effectiveness was $7,500 

per ton of SO2 removed. A lower cost option based on a single absorber tower based on 

information supplied by Intalco was analyzed by Ecology. A discussion of this option is 

included in Section 4, Ecology’s BART determination. 

The LSFO scrubber process oxidizes the spent slurry to gypsum sludge. The sludge volume 

would be 27,130 tons annually from the potline wet scrubber. It was not known at the time of 

the BART report preparation whether the gypsum would have commercial value or whether 

there would be any demand for it. If not sold, the sludges must be land filled. 

It is estimated that 182.5 million gallons of water will be required annually to operate the potline 

wet scrubber at a cost of approximately $97,000. This would increase Intalco’s daily water 

demand by approximately nine percent. 

A total of approximately 64.8 million kWh would be needed to operate the potline scrubber 

annually. This is equivalent to adding over 6,000 new households to the community.5 Table B-2 

in Appendix B summarizes the impacts analysis. 

 

5

 Calculated based on 2001 average energy usage per household for the U.S. as reported by the Department of 

Energy. See http://www.eia.doe.gov/emeu/reps/enduse/er01_us_tab1.html. 

Final December 2010 L - 70
March 3, 2009, Revised February 4, 2010 

 

Cost of anode grade coke is predicted to continue to rise in the future, as discussed in the 

previous pollution prevention section. Both increasing demand by the aluminum industry and 

the need of refineries to move toward using higher sulfur containing crude oil stocks drive 

Intalco’s prediction. US Gulf calcined anode grade coke increased from $118.50/mt to 

$244.75/mt between 1994 and 2006. The future rate of cost increase is anticipated to be greater 

due to the reasons discussed in the pollution prevention section. 

2.1.2 PM Control Options 

Fabric Filters

 

Fabric filters generally provide high collection efficiencies for both coarse and fine (submicron) 

particles. They are relatively insensitive to fluctuations in gas stream conditions. Efficiency is 

relatively unaffected by large changes in inlet dust loadings. Filter outlet air is very clean.6

Collected material is dry, which usually simplifies processing or disposal. Fabric filters are 

currently applied for controlling PM emissions from the potrooms at Intalco. 

Electrostatic Precipitators

Electrostatic Precipitators (ESPs) are capable of very high removal efficiencies for large and 

small particles.7 They offer control efficiencies that are comparable to fabric filters. Because of 

their modular design, ESPs, like fabric filters, can be applied to a wide range of system sizes. 

The operating parameters that influence ESP performance include particulate mass loading, 

particle size distribution, particulate electrical resistivity, space velocity, and precipitator voltage 

and current. 

 

Dusts with high resistivities are not well-suited for collection in dry ESPs because the particles 

are not easily charged. An ESP is technically feasible for control of PM from the potrooms at 

Intalco. 

Fabric filtration with dry alumina scrubbing has been widely used in the primary aluminum 

industry. Most smelters constructed within the past 20 years have used dry alumina scrubbing 

(either alumina injection or fluidized bed) with fabric filters to control particulate and fluoride 

emissions from potlines. A few plants use control systems consisting of ESPs to collect PM 

followed by spray towers to scrub gaseous fluoride. Wet systems have many disadvantages, 

such as corrosion by hydrofluoric acid, scaling, and acidic wastewater. ESPs and wet systems 

are no longer installed on new smelters in the U.S. 

 

 

6

 EPA 2003, “Air Pollution Control Technology Fact Sheet–Fabric Filter,” EPA-452/F-03-025, August 7. 7

 EPA 2003, “Air Pollution Control Technology Fact Sheet–Dry Electrostatic Precipitator,” EPA-452/F-03-028, 

August 7. 

Final December 2010 L - 71
March 3, 2009, Revised February 4, 2010 

 

Cyclones, Inertial Separators, and Wet Scrubbers 

Cyclones and inertial separators are used for collection of medium-sized and coarse particles. 

Wet scrubbers generally remove large particles and can remove small particles with the use of 

high-pressure drops. However, none of these devices are as effective at removing small and 

submicron particles as fabric filters and ESPs.8

Cost and Other Impacts of Feasible Particulate Potline Controls

Fabric filters are currently used on Intalco’s potlines. Since fabric filters have high control 

effectiveness similar to ESPs, are widely used for potline particulate control in the aluminum 

industry, and have process advantages relative to ESPs, no benefit was seen to switch from fabric 

filters to ESPs for PM control. Because no benefit was seen, no cost analysis of switching to an 

ESP-based particulate control was done. 

2.1.3 NOX Control Options 

Potentially applicable NOX emission controls include combustion controls and post-combustion 

controls. The pots are heated solely through the action of the electric reduction process. There is 

no combustion of fuel. There are also no large sources of nitrogen in the raw materials. This 

makes use of traditional combustion controls like staged combustion or low NOX burners not 

applicable to the potlines. The temperature of the potroom exhaust is approximately 180°F and 

the NOX concentration is less than one parts per million (ppm).

Possible post combustion controls include Selective Non-Catalytic Reduction (SNCR) and 

Selective Catalytic Reduction (SCR). Both involve injecting ammonia or urea into the gas 

stream to react with NOX to produce nitrogen and water. SNCR requires an operating 

temperature of 1,600°F to 2,100°F and inlet NOX concentrations typically from 200 to 400 ppm 

to be about 30-50 percent effective. SCR uses a catalyst to reduce the operating temperature 

requirement to between 500°F to 800°F, and can achieve up to 90 percent reduction of inlet NOX

concentrations to as low as 20 ppm. 

Since there is no external fuel or combustion zone in the smelting cells, there are no technically 

feasible pre-combustion NOX controls. Low temperature and NOX concentration make both 

SNCR and SCR post process NOX controls technically infeasible. 

2.1.4 Intalco’s BART Proposal for the Potlines 

For potline SO2 emissions, Intalco proposed BART to be the current level of control, which 

includes a maximum of three percent sulfur in the coke used to manufacture anodes. Use of wet 

scrubbing technology to reduce potline SO2 emissions was rejected as BART due to excessive 

costs: total cost effectiveness of $7,500 per ton of SO2 removed and capital and total annualized 

 

8

 AWMA 2000, “Air Pollution Engineering Manual,” Second Edition. 

Final December 2010 L - 72
March 3, 2009, Revised February 4, 2010 

 

costs of $234.5 million. A potline wet scrubber would also have substantial non air quality 

impacts, including increased energy usage, added water consumption, and solid waste 

generation. 

For PM emissions, Intalco proposed BART to be the current level of control, which is the use of 

baghouses to control PM emissions from the alumina dry scrubbers, and wet roof scrubbers to 

control secondary PM emissions from the potroom roofs. 

For NOX emissions, Intalco proposed BART to be no controls. 

2.2 Anode Bake Furnace Control Options 

The anode bake furnace process is discussed in Section 1.3.2 of this report. Emissions due to 

anode coke and pitch are similar to those from the potlines, so the same BART control options 

considered for the potlines are applicable to the bake furnace emissions exhaust. It is smaller, 

with only about 12 percent of the airflow volume of the combined potlines emission scrubber. It 

is natural gas fired rather than electrically heated, so it has products of combustion including 

NOX. 

2.2.1 SO2 Control Options 

A wet scrubber was identified as a technically feasible add-on pollution control option for the 

anode bake furnace. The anode bake furnace is a smaller source than the potlines and has a 

lower exhaust gas flow rate. A separate vendor cost proposal was not obtained for the anode 

bake furnace, but an SO2 removal efficiency of 95 percent is assumed to be feasible. Wet 

scrubber costs for the anode bake furnace were scaled from the LSFO potline wet scrubber 

vendor quotes. 

The estimated installed capital cost to add a wet scrubber to remove 95 percent of the SO2 from 

the anode bake furnace exhaust would be approximately $29.5 million with an annualized cost of 

$6.3 million per year. The wet scrubber cost effectiveness is $36,400 per ton of SO2 removed. 

The wet scrubber also has an energy impact of 6,570,000 kW-hr/yr as well as solid waste 

impacts associated with disposal of gypsum sludge from the scrubber and water use impacts 

from scrubber operation. The impacts are summarized in Table B-2 of Appendix B. 

The pollution prevention option of reducing the sulfur content of the anode coke is available for 

the anode bake oven as well as the potlines. See the potline pollution prevention discussion in 

Section 2.1.1. 

2.2.2 PM Control Options 

Dry alumina injection with fabric filtration is currently used for PM control on the anode bake 

furnace. An ESP is also a technically feasible control, with a similar fine particulate PM capture 

Final December 2010 L - 73
March 3, 2009, Revised February 4, 2010 

 

 

efficiency. As described in Section 2.1.2, cyclones, inertial separators, and wet scrubbers are not 

as effective at removing small and submicron particles as fabric filters and ESPs. 

2.2.3 NOX Control Options 

Advanced firing system: NOX emissions from anode baking depend on operating practices and 

burner controls. The traditional methods of preventing NOX formation using staged combustion 

or low NOX burners are not applicable because of the unique configuration of an anode baking 

ring furnace, with fuel injected at several points in narrow flues. However, advanced firing 

systems that measure and regulate fuel flow precisely using a computerized control system can 

reduce total fuel usage. This will also reduce NOX emissions. Prevention of NOX formation 

using a more efficient advanced firing control system is technically feasible for the anode bake 

furnace at Intalco. Total gas usage is projected to be reduced by 20 percent, which would result 

in a corresponding 20 percent reduction in NOX emissions, or approximately 27 tons/year. 

The LoTOXTM system is the patented technology of BOC Gases. In this NOX removal system, 

ozone is injected into the exhaust gas stream in order to oxidize insoluble NOX to soluble 

nitrogen compounds, including N2O5. N2O5 is highly soluble and reacts with moisture in the gas 

stream to form nitric acid. A scrubber is required downstream of the LoTOxTM system to remove 

the nitric acid formed by the reaction of N2O5 and moisture in the gas stream. The ozone is 

typically generated on site and on demand. Since LoTOxTM is a low temperature system, it does 

not require heat input and the low operating temperature (150 to 250°F) allows for stable and 

consistent control even with variations in flow, load, and NOX concentrations.9

Use of the LoTOxTM system has not been demonstrated at an aluminum plant. Research 

indicates that application of the LoTOxTM technology has been limited to a sulfuric acid 

regeneration plant, a lead smelting reverbatory furnace, a stainless steel plant, a coal-fired 

electric generation unit, and two fluidized-bed catalytic cracking units (FCCU) at refineries.10 11

Reported NOX removal efficiencies for the LoTOxTM system are on the order of 90 to 95 percent. 

The temperature of the anode baking emission exhaust (approximately 200°F) is within the 

temperature range where LoTOxTM could be used. Although this technology has not been 

demonstrated on an anode bake furnace, low-temperature oxidation technology may be 

technically feasible for reducing anode bake furnace NOX emissions. At a control efficiency of 

90 percent for NOX emissions when combined with wet scrubbing, the resulting reduction in 

NOX emissions would be 122 tons/year. 

Intalco made the case that cost data for the LoTOxTM system was not readily available. To show 

some cost estimation, Intalco noted that the LoTOxTM system would also require a scrubber 

9

 BOC Process Gas Solutions, 2001, Low Temperature Oxidation System Demonstration at RSR Quemetco, Inc., 

City of Industry, California, June 28. See www.arb.ca.gov/research/icat/projects/boc.pdf. 10 EPA, February 2005, “Using Non-Thermal Plasma to Control Air Pollutants,” EPA-456/R-05-001. See 

www.epa.gov/ttn/catc/dir1/fnonthrm.pdf. 11 EPA RACT/BACT/LAER Clearinghouse (RBLC) database. 

Final December 2010 L - 74
March 3, 2009, Revised February 4, 2010 

 

similar to the one described earlier for SO2 control. That would make the cost of the entire 

LoTOxTM system installation more than the previously estimated SO2 scrubber cost of $29.5 

million. NOX emissions are lower than SO2 emissions for the anode bake furnace, so the cost per 

ton values for NOX would be higher than the $36,400 estimated for SO2. Since cost for the 

LoTOxTM system itself was not available, it is not possible to calculate a cost per ton for the total 

system based on both NOX and SO2. To give a sense of the possible minimum cost, if the 

LoTOxTM system were free, the cost would be greater than $18,000 per ton of total pollutants 

removed. 

2.2.4 Intalco’s BART Proposal for the Anode Bake Furnace 

Intalco proposed that the existing potline SO2 control pollution prevention limit of three percent 

sulfur in the coke to be BART for anode bake furnace SO2 emissions. The cost effectiveness of 

wet scrubbing to reduce SO2 emissions was determined to be excessive at $36,400 per ton of SO2

removed. As discussed below in Section 3, addition of a wet scrubber to the anode bake furnace 

would reduce the visibility impact on Olympic National Park by only 0.024 dv. 

The existing level of control (based on baghouses on the alumina dry scrubbers) was proposed to 

be BART for PM emissions. 

BART for anode bake furnace NOX emissions was proposed to be no additional controls. The 

use of an advanced firing system for reduced energy use was rejected as BART because the 20 

percent reduction in NOX emissions would result in a negligible 27 ton per year NOX reduction 

and visibility improvement. Emissions of all pollutants (SO2 and NOX) from the anode bake 

furnace are responsible for only about one percent of the visibility impact on Olympic National 

Park; the most impacted Class I Area (see Section 3 below). The use of LoTOxTM was rejected 

as BART because the technology is not available or demonstrated in practice for aluminum 

anode bake furnace exhausts. 

2.3 Aluminum Holding Furnaces 

2.3.1 Aluminum Holding Furnaces Control Options 

The 12 holding furnaces at Intalco are heated by natural gas burners, and vary in size, with the 

largest of these furnaces having a natural gas rated burner capacity of 22 MMBtu/hr. Emissions 

come from combustion of natural gas in the burners. There is currently no emission controls 

associated with the aluminum furnaces at Intalco. 

2.3.2 Intalco’s BART Proposal for the Aluminum Holding Furnaces 

Intalco proposed that BART for the aluminum holding furnaces was no controls. The proposal 

rejected additional controls as BART because the modeling analysis discussed in Section 3 

below showed that any visibility improvement would be negligible because the existing burners 

have a negligible contribution to visibility impacts. 

Final December 2010 L - 75
March 3, 2009, Revised February 4, 2010 

 

2.4 Material Handling and Transfer Operations 

2.4.1 Material Handling and Transfer Operations and Other Miscellaneous 

Operations Control Options 

The remaining emission units are various material handling and transfer operations, natural gas, 

diesel, and propane combustion, and other small miscellaneous sources that support the potlines 

and anode bake furnace. Aside from emissions from natural gas combustion, emissions from 

most of the support operations consist of relatively small amounts of PM that are controlled by 

fabric filter control devices. 

2.4.2 Intalco’s BART Proposal for the Material Handling and Transfer 

Operations 

Intalco showed that PM emissions from the BART-eligible material handling and transfer 

operations were all controlled using fabric filter technology. This existing level of emissions 

control was proposed to be BART for these material handling and transfer operations. 

3. VISIBILITY IMPACTS AND DEGREE OF IMPROVEMENT 

A baseline Class I area visibility impact analysis was performed on the BART-eligible 

emission units at Intalco using the CALPUFF model with four kilometer grid spacing as 

recommended by the Oregon/Idaho/Washington/EPA-Region 10 BART modeling protocol. The 

modeled or projected 98th percentile visibility impacts for the entire facility exceed the 0.5 

deciview (dv) contribution threshold in seven Class I areas as shown in Table 3-1. 

Table 3-1. BASELINE VISIBIITY MODELING RESULTS 

Class I Area 

2003 2004 2005 

Modeled 

98th

Percentile 

(deciview) 

Number of 

Days 

Exceeding 

0.5 dv 

Modeled 

98th

Percentile 

(deciview) 

Number of 

Days 

Exceeding 

0.5 dv 

Modeled 

98th

Percentile 

(deciview) 

Number of 

Days 

Exceeding 

0.5 dv 

Alpine Lakes Wilderness Area 1.244 36 0.965 37 0.881 23 

Goat Rocks Wilderness Area 0.500 8 0.579 10 0.317 3 

Glacier Peak Wilderness Area 1.161 37 1.156 38 0.736 23 

Mount Adams Wilderness Area 0.456 7 0.472 6 0.357 2 

Mount Rainier National Park 0.843 22 1.052 26 0.629 15 

North Cascades National Park 1.376 65 1.395 56 1.138 32 

Olympic National Park 2.363 59 1.858 53 2.136 45 

Pasayten Wilderness Area 0.866 30 0.871 33 0.659 13 

Intalco’s modeling consultant evaluated the effects of the different emission sources at the 

Intalco facility to determine which operations resulted in the greatest visibility impacts. This 

Final December 2010 L - 76
March 3, 2009, Revised February 4, 2010 

 

analysis indicated that the potlines are responsible for 98 percent of the visibility impact on the 

most impacted Class I area, and 96 percent of that impact is from the SO2 emissions. Of the 

remaining two percent of the visibility impact, the anode bake furnace is the next largest source 

at about one percent of the impact. The other sources in total are the sources of the remaining 

one percent of the impact. 

An evaluation of the potential improvement in visibility that would result from application of 

feasible pollution prevention/add-on control options was done. CALPUFF modeling was 

performed for two control scenarios: one with wet SO2 scrubbing applied to the potline and one 

with wet SO2 scrubbing applied to the anode bake furnace. In general, this modeling was the 

same as the baseline modeling except stack data and emission data associated with the 

application of the feasible add-on controls were used as model inputs. Emission information for 

both baseline and control scenario modeling is found in Appendix B. 

The addition of a potline wet scrubber reduced modeled visibility impacts in all Class I areas. 

For example, the baseline modeling results indicate that the highest 98th percentile visibility 

impact from Intalco’s BART-eligible sources at Olympic National Park estimated that wet 

scrubbers installed on the potlines would provide up to 1.172 dv of visibility improvement. The 

modeled visibility improvements from adding a wet scrubber at the anode bake furnace only are 

much smaller. The post-control modeling results for the anode bake furnace indicate visibility 

might be improved by up to 0.024 dv at Olympic National Park. 

4. ECOLOGY’S BART DETERMINATION 

Ecology’s BART determination for Intalco is given in Table 4-1. A more detailed description of 

each decision follows. 

 

Table 4-1. BART DETERMINATION FOR INTALCO

Pollutant BART Determination 

Potlines 

SO2

Use of the current level of control, which is a pollution prevention limit of 3% 

sulfur in the coke used to manufacture anodes. 

PM 

Use of the current level of control, which is the use of baghouses to control 

PM emissions from the alumina dry scrubbers, and wet roof scrubbers to 

control secondary PM emissions from the potroom roofs. 

NOX No control 

Anode Bake Furnace 

SO2

Use of the current level of control, which is a pollution prevention limit of 3% 

sulfur in the coke used to manufacture anodes. 

PM Use of the current level of control, which is the use of a baghouse. 

NOX No control 

Aluminum Holding Furnaces 

SO2 No control 

Final December 2010 L - 77
March 3, 2009, Revised February 4, 2010 

 

Pollutant BART Determination 

PM No control 

NOX No control 

Material Handling and Transfer Operations 

SO2 No control 

PM Use of the current level of control, which is use of fabric filters. 

NOX No control 

Aluminum Potlines 

Ecology determined that for SO2 emissions from the potlines, BART is the current level of 

control, which is a pollution prevention limit of three percent sulfur in the coke used to 

manufacture anodes. 

Ecology agrees with Intalco that a pollution prevention limit based on coke sulfur content below 

three percent is infeasible as BART based on an evaluation of the future availability of petroleum 

coke with lower sulfur content. 

Ecology rejected the use of wet scrubbing technology as BART to reduce potline SO2 emissions 

because of its excessive costs. Ecology has evaluated the cost estimate provided by Alcoa for 

this plant including adjusting Alcoa’s cost estimates for various items like operational and 

maintenance labor. For the proposed two absorption tower design, our revised annualized cost 

was $6,574 per ton of SO2 removed. The capital and total annualized costs were estimated to be 

$208.5 million and $40.9 million per year, respectively. 

A single absorption tower design option was included in one of the two original Tennessee plant 

scrubber system proposals (by Babcock), but not evaluated by Intalco’s within its BART 

proposal for Intalco This design would cost less, principally by eliminating the second, backup 

scrubber tower. With the single absorber tower configuration, if the scrubber tower needed to be 

taken down for maintenance, the primary control system emissions would need to bypass the 

absorber tower while maintenance occurs, resulting in SO2 emissions identical to the current 

rates during the bypassing. Unlike an electrical power plant where routine and planned 

shutdowns occur during which maintenance can be carried out, an aluminum smelter does not 

normally stop operating once it has started. Babcock estimated that the single tower design 

reduced the Total Capital Investment Costs (TCIC) by 28.1 percent, or to 71.9 percent of their 

two scrubber system proposal. Ecology scaled this cost reduction to the Intalco cost estimate, 

and included additional cost reductions in annual operating labor and maintenance labor as much 

as practical. The resulting capital and total annualized costs were $185.1 million and $38.7 

million respectively. This gave a cost effectiveness of $6,145 per ton of SO2 removed assuming 

an identical SO2 removal rate. Any direct venting of the emission gasses during maintenance of 

the absorber tower would lower the SO2 tons removed and increase this dollars/ton cost 

effectiveness estimate. Ecology finds the single absorber option to not be cost effective. 

Final December 2010 L - 78
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Any potline wet scrubber system would also have substantial energy and non air quality impacts, 

including electricity, water, and waste disposal. Specifically for the limestone control option, 

Intalco has estimated that there would be an increased energy usage of 64,824,000 kWh of 

electricity per year, added water consumption of 183 million gallons per year, a need to 

discharge wastewater from the scrubber system, and solid waste generation of 27,000 tons/year. 

In response to comments by Ecology on the wet scrubber option, Intalco identified additional 

impediments to utilizing a wet scrubbing system. The most important for implementing a wet 

scrubbing system is that they currently purchase potable water for industrial purposes and have 

turned over water rights previously issued to Intalco to the water district. The result of this water 

transfer is the plant would have difficulty in acquiring water rights for this consumptive 

industrial purpose. 

Based on the cost effectiveness and the non air quality impacts of a wet scrubbing system, 

Ecology determined BART for SO2 is the current level of emissions control. 

Ecology determined that for PM emissions from the potlines, BART is the current level of 

control, which is the use of baghouses to control PM emissions from the alumina dry scrubbers, 

and wet roof scrubbers to control secondary PM emissions from the potroom roofs. 

Ecology determined that there are no feasible technologies for the control of NOX from the 

potlines. BART for NOX is determined to be no controls. 

Anode Bake Furnace 

Ecology determined that the petroleum coke sulfur limit accepted as BART for the potlines is 

also BART for anode bake furnace SO2 emissions. The cost of wet scrubbing to reduce SO2

emissions would be excessive at $36,400 per ton of SO2 removed while providing minimal 

visibility improvement. 

Ecology determined that the existing level of control (based on baghouses on the alumina dry 

scrubbers) is BART for PM emissions. 

Ecology determined that BART for anode bake furnace NOX emissions is no controls. The use 

of an advanced firing system for reduced energy use was rejected as BART because the 

technology would result in a negligible emission reduction and visibility improvement. 

Similarly, the use of LoTOxTM was rejected as BART because the cost of the technology would 

be excessive and it has not been demonstrated in practice on aluminum plant anode bake 

furnaces. 

Aluminum Holding Furnaces

 

Final December 2010 L - 79
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Ecology determined that BART for the aluminum holding furnaces is no controls. The use of 

additional controls was rejected as BART because any visibility improvement would be 

negligible due to the low level of emissions from the natural gas-fired burners. 

Material Handling and Transfer Operations 

Ecology determined that since PM emissions from the BART-eligible material handling and 

transfer operations are all controlled using fabric filter technology, the existing level of emissions 

control is BART for these material handling and transfer operations. 

Ecology determined that BART for NOX and SO2 emissions from material handling and transfer 

operations is no controls. Material handling and transfer operations are a negligible source of 

NOX and SO2 emissions. Additional control of these pollutants would provide negligible 

visibility improvement. 

 

Final December 2010 L - 80
March 3, 2009, Revised February 4, 2010 

 

APPENDIX A 

DESCRIPTION OF AVAILABLE SO2 POTLINE CONTROL OPTIONS 

Technology Description 

Limestone Slurry 

Forced Oxidation 

(LSFO) 

Limestone slurry forced oxidation (LSFO) is used extensively in the 

utility flue gas desulphurization (FGD) market. It has not been used on 

an aluminum smelter. The raw material is finely ground limestone. The 

most commonly used equipment is an open, multi-level, countercurrent 

spray tower scrubber equipped with spray nozzles to inject the limestone 

slurry droplets into the gas stream. Liquor is collected at the bottom of 

the tower and sparged with air to oxidize the calcium sulfite to calcium 

sulfate to enhance the settling properties of the calcium sulfate. 

Recirculation pumps circulate the scrubbing liquor to the spray nozzles. 

SO2 removal efficiencies of 90% have been achieved. The bleed from 

the scrubber is sent to a dewatering system to remove excess moisture. 

For an aluminum smelter, the process will produce either solid gypsum 

waste or commercial-grade gypsum suitable for reuse as a cement 

additive if a cement production facility is available and willing to accept 

the material. Only a very small purge or blowdown stream is required. 

Limestone Slurry 

Natural Oxidation 

(LSNO) 

Limestone slurry natural oxidation (LSNO) is very similar to LSFO. 

The major difference is the absence of an oxidation stage. The 

gypsum/calcium sulfite product is essentially a waste product with 

limited possibilities of use for agricultural purposes. 

Conventional Lime 

Wet Scrubbing 

Conventional lime wet scrubbing is also similar to LSFO except that the 

raw material is hydrated lime or quick lime that is either slaked on-site 

or purchased in the slaked form. The system typically uses forced 

oxidation, although natural oxidation is possible. The process will 

produce either solid gypsum waste or commercial-grade gypsum 

suitable for reuse as a cement additive if a cement production facility is 

available and willing to accept the material. 

Seawater 

Scrubbing 

Seawater scrubbing is a method for controlling SO2 emissions in which 

seawater is used to absorb SO2 in exhaust gases. Seawater is slightly 

alkaline (with a pH of approximately 8). SO2 has a high solubility in 

seawater. Absorbed SO2 is subsequently oxidized to sulfates by the use 

of aeration and the pH is adjusted by the addition of additional seawater. 

There are three main steps in this process: absorption, oxidation, and 

neutralization. Seawater is passed countercurrent through the gaseous 

exhaust stream, typically using a spray column in the aluminum 

industry. SO2 preferentially dissolves in the seawater. Removal 

efficiencies of 85 to 95% have been measured in practice. The clean 

Final December 2010 L - 81
March 3, 2009, Revised February 4, 2010 

 

Technology Description 

exhaust gas is de-misted prior to release to the atmosphere. The 

acidified seawater is then passed to an oxidation basin in which air is 

blown through the effluent. The additional oxygen ensures that the 

dissolved SO2 is converted to sulfates. Finally, additional fresh seawater 

is added to raise the pH to neutral (or slightly alkaline) and the seawater 

is discharged back into the ocean. 

The effluent from this process will typically have a temperature increase 

of about 1°C and will have a change in sulfate concentration of 

approximately 2 to 5% above background.12 13 Scrubbing of the potline 

emissions also adds fluoride and trace amounts of polycyclic aromatic 

hydrocarbons (PAHs) to the effluent seawater. The volume of seawater 

required varies with exhaust flow rate and SO2 loading in the gaseous 

exhaust stream. At Intalco, the volumetric flow rate needed was 

estimated to be approximately 2.2 million gallons per hour. 

A global review of feasible control technologies identified seawater 

scrubbing as having been installed at seven aluminum smelters, none of 

which are in the U.S. Even though this technology has been identified 

as a control technology in operation at six primary aluminum ore 

reduction plants in Norway and one primary aluminum ore reduction 

plant in Sweden, there are two reasons why this technology is not 

feasible at Intalco: 

1. Federal Clean Water Act Section 304(b) effluent limitations 

guidelines would not allow discharge of the scrubber solutions to 

the nearby salt water without extensive treatment to remove the 

sulfides, fluorides, and other pollutants. Removal of potline 

fluoride from the seawater scrubber effluent may be feasible, but 

would also require precipitation of many other naturally 

occurring salts in the seawater (chlorides, sulfates, other 

fluorides, etc.), resulting in the unnecessary generation of large 

amounts of sludge for land disposal. Seawater scrubbing is, 

therefore, not a viable alternative for smelters in the U.S., 

especially when compared with other scrubbing technologies that 

use fresh water and require treatment/disposal for only those 

salts present in the potline exhaust. 

2. The portion of Puget Sound where seawater would be withdrawn 

and discharged has been included as part of the Cherry Point 

 

12 Information from the ALSTOM Seawater FGD–Environmental Impact website at 

www.environment.power.alstom.com/home/power/seawater_fgd/environmental_impact.htm. 13 Kwawaji, Akili D., et al. 2005. “Seawater Scrubbing for the Removal of Sulfur Dioxide in a Steam Turbine 

Power Plant.” Proceeding of the PWR2005 ASME Power Conference. April 5-7. Chicago, IL. 

Final December 2010 L - 82
March 3, 2009, Revised February 4, 2010 

 

Technology Description 

Aquatic Reserve that was established in 2000. The construction 

of intake and/or discharge structures within the Cherry Point 

Aquatic Reserve would require an impact analysis, assessment, 

and DNR authorization of any environmental impacts associated 

with a seawater scrubbing system. Since more than seven years 

have passed since Cherry Point was designated as an aquatic 

reserve and the initial SEPA evaluation has yet to be completed, 

the time required to complete an analysis of the environmental 

impacts associated with a seawater scrubbing system and obtain 

the requisite authorizations for a system that withdraws seawater 

from and discharges scrubber liquor into the Cherry Point 

Aquatic Reserve would make this technology infeasible for 

BART compliance. 

Dual Alkali 

Sodium/Lime 

Scrubbing 

(dilute mode) 

Dual alkali sodium/lime scrubbing (dilute mode) uses a caustic sodium 

solution in the scrubber tower. A portion of the scrubbing liquid is 

discharged to a neutralization stage where lime slurry is used to 

regenerate the caustic, which is returned to the scrubber. The bleed from 

the scrubber is sent to a dewatering system to produce a gypsum 

byproduct. The process will produce either solid gypsum waste or 

commercial-grade gypsum suitable for reuse as a cement additive. Dual 

alkali sodium/lime scrubbing (dilute mode) is not currently marketed by 

major FGD vendors because the system is too complicated and 

expensive. Because of lack of availability and anticipated excessive 

cost, dual alkali sodium/lime scrubbing is determined to be not 

technically feasible. 

Conventional 

Sodium Scrubbing 

Conventional sodium scrubbing has been installed in at least 12 

aluminum smelters around the world. An alkaline solution of either 

soda ash or sodium hydroxide is pumped into the scrubbing tower and 

recirculated through a network of spray nozzles. Atomized droplets 

contact the up-flowing gas containing SO2. Where this technology has 

been deployed, the liquid effluent containing dissolved salts, including 

sodium and fluorides, has been discharged into a large receiving stream 

or an open body of water without treatment. As discussed earlier in 

conjunction with seawater scrubbing, untreated discharge is not feasible 

for Intalco. As a result of the inability to discharge effluent, treated or 

otherwise, into a receiving water, Alcoa determined conventional 

sodium scrubbing to not be technically feasible. 

Dry Injection 

In dry injection, a reactive alkaline powder is injected into a furnace, 

ductwork, or a dry reactor. Typical removal efficiencies with calcium 

adsorbents are 50 to 60% and up to 80% with sodium base adsorbents. 

However, as with wet scrubbing, disposal of waste using sodium 

Final December 2010 L - 83
BART Support Document Page 21 of 23 

Alcoa Intalco Works 

March 3, 2009, Revised February 4, 2010 

 

Technology Description 

adsorbents must consider their high solubility in water compared to 

those from calcium adsorbents. The temperature range over which 

scrubbing has been used is 300 to 1,800°F; the minimum temperature is 

300 to 350°F. Dry systems are rarely used and according to EPA, only 

3% of FGD systems installed in the U.S. are dry systems.14 The dry 

waste material is removed using particulate control devices such a fabric 

filter or an electrostatic precipitator (ESP).

Semi-Dry 

Scrubbing 

Semi-dry scrubbing is more commonly referred to as spray drying. 

Calcium hydroxide slurry (lime mixed with water) is introduced into a 

spray dryer tower. Sodium compounds can be used, but as with the dry 

scrubber, the high solubility of the sodium-based waste products in 

water complicates disposal of the waste. The slurry is atomized and 

injected into a reactor with the exhaust gases, where droplets react with 

SO2 as the liquid evaporates. 

This system is categorized as a semi-dry system because the end product 

of the SO2 conversion reaction is a dry material. The dry waste product 

is collected in the bottom of the spray dryer reactor and a fabric filter or 

ESP downstream of the spray dryer removes the CaSO3, CaSO4, and 

unreacted lime. This air pollution control system uses water for 

evaporative cooling and for the SO2 reaction. It operates in a 

temperature range of 300 to 350°F because the temperature of the gases 

must be high enough to evaporate the water portion of the slurry. 

Approximately 12% of the FGD systems installed in the U.S. are spraydry systems15 with typical SO2 removal efficiencies in the range of 80 to 

90 percent. Unlike a wet scrubbing system, there is no liquid blowdownstream from the dry system and the collected solids are typically 

land filled. 

 

14 EPA 2003, “Air Pollution Control Technology Fact Sheet–Flue Gas Desulfurization,” EPA-452/F-03-034. 

15 Ibid. 

Final December 2010 L - 84
February 3, 2009 

APPENDIX B. LSFO SCRUBBER CONTROL SCENARIOS–EMISSIONS AND IMPA

Table B-1. EMISSION RATES FOR SO2 CONTROL SCENARIOS1

Control 

Scenario 

SO2 Control 

Technology 

Evaluated 

SO2 NO2 PM2.5 

Emissions 

(tons/yr) 

% Reduction 

(increase)2

Emissions 

(tons/yr) 

% Reduction 

(increase) 2

Emissions 

(tons/yr) 

% Reduction 

(increase) 2

Em

(to

Current Allowable Emissions 

Operating Limit of 3% Sulfur in Coke 

7,076 136 693 

Scenario 1 

Plus LSFO Scrubber Only for Potlines 

854 88 136 0 984 (42) 1

Scenario 2 

Plus LSFO Scrubber Only for Anode Bake Furnace 

6,904 2 136 0 747 (8) 

1. Total emission rate for the potline primary control system, the potline secondary control system emissions, and the anod

2. Compared with current potential emissions. Intalco’s BART technical analysis provides information on increases in em

due to LSFO scrubbers. Because sulfate dominates visibility impacts on Class I areas, these small increases in particulathe BART determination.

L - 85
BART Support Document 

Alcoa Intalco Works February 3, 2009 

Table B-2. SUMMARY OF THE IMPACTS ANALYSIS FOR SO2 CONTROL SCENAR

Control 

Scenario 

SO2 Control 

Technology 

Evaluated 

SO2

Emission 

Rate1

(tons/yr) 

SO2

Emission 

Reductions2

(tons/yr) 

Installed 

Capital Cost 

Total 

Annualized 

Control 

Costs 

Cost 

Effectiveness 

(per ton SO2

removed) 

Energy 

Impact 

(kW-hr/yr) 

En

Current Allowable Emissions 

Operating Limit of 3% Sulfur in Coke 

7,076 

Scenario 1 

Plus LSFO Scrubber Only for Potlines 

854 6,223 $234,531,049 $46,820,000 $7,500 64,824,000 

27,1disp182.mak

Scenario 2 

Plus LSFO Scrubber Only for Anode Bake Furnace 

6,904 172 $29,482,194 $6,227,000 $36,400 6,570,000 

639.disp12.8 mak

1. Total emission rate for the potline primary control system, the potline secondary control system, and the anod2. Compared with current potential emissions. 

L - 86
February 3, 2009 

 

APPENDIX C. ACRONYMS/ABBREVIATIONS 

BACT Best Available Control Technology 

BART Best Available Retrofit Technology 

dv Deciview(s) 

CO Carbon Monoxide 

Ecology Washington State Department of Ecology 

EPA United States Environmental Protection Agency 

ESPs Electrostatic Precipitators 

Intalco Alcoa Intalco Works 

LSFO Limestone Slurry Forced Oxidation 

LSNO Limestone Slurry Natural Oxidation 

mt Metric Ton 

NOX Nitrogen Oxides 

PM Particulate Matter 

PM10 Particulate Matter (with a mean diameter less than 10 microns) 

ppm Parts per Million 

PSCAA Puget Sound Clean Air Agency 

SIP Regional Haze State Implementation Plan 

SO2 Sulfur Dioxide 

VOC Volatile Organic Compound 

Final December 2010 L - 87
BART DETERMINATION FOR ALCOA INTALCO WORKS 

FERNDALE, WASHINGTON 

Prepared for: 

Alcoa Intalco Works 

Ferndale, Washington 

Prepared by: 

ENVIRON Corporation 

6001 Shellmound Street, Suite 700 

Emeryville, California 94608 

November 2007 

Contract Number 03-8979C 
Intalco BART Determination FINAL.doc - i - 

TABLE OF CONTENTS 

1.0 INTRODUCTION.......................................................................................................... 1-1

2.0 IDENTIFICATION OF BART-ELIGIBLE UNITS AT INTALCO ........................ 2-1

3.0 BART-ELIGIBLE EMISSION UNIT GROUP DESCRIPTION ............................. 3-1

3.1 PRIMARY ALUMINUM REDUCTION PROCESS DESCRIPTION........................................ 3-1 

3.1.1 EXISTING POTLINE EMISSIONS CONTROL......................................................... 3-2 

3.1.2 ANODE BAKE FURNACE EMISSIONS CONTROL................................................. 3-2 

3.1.3 ALUMINUM HOLDING FURNACE EMISSIONS CONTROL .................................... 3-3 

4.0 BASELINE CONDITIONS AND VISIBILITY IMPACTS FOR BART-ELIGIBLE 

UNITS ............................................................................................................................. 4-1

4.1 CALPUFF MODEL AND BASELINE EMISSION INPUTS ............................................... 4-1 

4.2 SCREENING-LEVEL MODELING ANALYSIS................................................................. 4-1 

4.3 REFINED MODELING ANALYSIS................................................................................. 4-2 

5.0 BART ANALYSIS FOR BART-ELIGIBLE EMISSION UNITS ............................ 5-1

5.1 AVAILABLE AND TECHNICALLY FEASIBLE EMISSION CONTROL OPTIONS ................. 5-1 

5.1.1 POTLINE EMISSIONS AND EXISTING CONTROLS ............................................... 5-1 

5.1.2 ANODE BAKE FURNACE EMISSIONS AND EXISTING CONTROLS ....................... 5-1 

5.1.3 POTENTIALLY APPLICABLE BART CONTROL OPTIONS FOR SO2 ..................... 5-2 

5.1.4 POTENTIALLY APPLICABLE BART CONTROL OPTIONS FOR PM.................... 5-12 

5.1.5 POTENTIALLY APPLICABLE BART CONTROL OPTIONS FOR NOX .................. 5-13 

5.1.6 SUMMARY OF TECHNICALLY FEASIBLE BART CONTROL OPTIONS ............... 5-15 

5.2 CONTROL EFFECTIVENESS OF FEASIBLE OPTIONS ................................................... 5-17 

5.2.1 SO2 WET SCRUBBING .................................................................................... 5-17 

5.2.2 SO2 POLLUTION PREVENTION ........................................................................ 5-18 

5.2.3 ANODE BAKE FURNACE ADVANCED FIRING SYSTEM .................................... 5-18 

5.2.4 ANODE BAKE FURNACE LOTOXTM SYSTEM .................................................. 5-18 

5.3 EVALUATION OF COSTS AND OTHER IMPACTS......................................................... 5-18 

5.3.1 COST IMPACTS FOR FEASIBLE CONTROLS ...................................................... 5-18 

5.3.2 ENERGY IMPACTS........................................................................................... 5-21 

5.3.3 GREENHOUSE GAS GENERATION ................................................................... 5-21 

5.3.4 NON-AIR QUALITY ENVIRONMENTAL IMPACTS............................................. 5-21 

5.3.5 REMAINING USEFUL LIFE............................................................................... 5-22 

5.4 EVALUATE VISIBILITY IMPACTS .............................................................................. 5-22 

6.0 DETERMINATION OF BART.................................................................................... 6-1

6.1 ALUMINUM POTLINES................................................................................................ 6-1 

6.2 ANODE BAKE FURNACE............................................................................................. 6-1 

6.3 ALUMINUM HOLDING FURNACES .............................................................................. 6-2 

6.4 MATERIAL HANDLING AND TRANSFER OPERATIONS................................................. 6-2 
Intalco BART Determination FINAL.doc - ii - 

TABLES 

3-1 Primary Aluminum Reduction Emission Units 

4-1 Source Input Data for Baseline Modeling – Point Sources 

4-2 Source Input Data for Baseline Modeling – Line Sources 

4-3 Source Input Data for Baseline Modeling – Area Sources 

4-4 Source Input Data for Baseline Modeling – Volume Sources 

4-5 Screening Baseline Visibility Modeling Results 

4-6 Refined Baseline Visibility Modeling Results 

4-7 Culpability Analysis for Refined Baseline Visibility Modeling Results in Olympic 

National Park 

5-1 RBLC Database Search Results for Primary Aluminum Facilities 

5-2 Post Control SO2 Emission Rates 

5-3 Summary of Impacts Analysis for SO2 Control Scenarios 

5-4 Source Input Data for Post Control SO2 Modeling 

5-5 Post Control SO2 Visibility Modeling Results 

FIGURES 

5-1 Wet Scrubber Process Flow Diagram 

APPENDICES 

A BART Modeling Results 

B Business Confidential Information 

C Pre-Feasibility Report 

D Wet Scrubber Economic and Energy Impact 

E Greenhouse Gas Emission Calculations 
Intalco BART Determination FINAL.doc - iii - 

ACRONYMS 

acfm actual cubic feet per minute 

AWMA Air and Waste Management Association 

BACT Best Available Control Technology 

BART Best Available Retrofit Technology 

CAA Clean Air Act 

CFR Code of Federal Regulations 

DNR Department of Natural Resources 

dv deciview 

ELG Effluent Limitations Guidelines 

ESP Electrostatic Precipitator 

FGD Flue Gas Desulfurization 

Intalco Alcoa Intalco Works 

LAER Lowest Achievable Emissions Rate 

lb/day pounds per day 

LSFO Limestone Slurry Forced Oxidation 

LSNO Limestone Slurry Natural Oxidation 

MW Megawatt 

NESHAP National Emission Standards for Hazardous Air Pollutants 

NOx Nitrogen Oxides 

PAH Polycyclic Aromatic Hydrocarbons 

PM Particulate Matter 

PM2.5 Particulate Matter less than 2.5 micrometers in diameter 

PM10 Particulate Matter less than 10 micrometers in diameter 

ppm parts per million 

ppmv parts per million by volume 

RACT Reasonably Available Control Technology 

RBLC RACT/BACT/LAER Clearinghouse 

SCR Selective Catalytic Reduction 

SEPA State Environmental Protection Act 

SNCR Selective Non-Catalytic Reduction 

SO2 Sulfur Dioxide 

USEPA United States Environmental Protection Agency 
Intalco BART Determination FINAL.doc - ES-1 - 

EXECUTIVE SUMMARY 

The Clean Air Act (CAA) requires the protection of visibility in 156 scenic areas across the 

United States. Under CAA Section 169A(b)(2)(A), states must require certain existing stationary 

sources to install Best Available Retrofit Technology (BART). Alcoa, Inc. – Intalco Works 

(Intalco) is a “BART-eligible” source. A BART determination is required because Intalco emits 

air pollutants that may reasonably be anticipated to contribute to impairment of visibility in a 

Class I area. 

The BART analysis contained herein lists the individual BART-eligible emission units and 

evaluates visibility impacts, control option feasibility, cost effectiveness and visibility 

improvement. The BART evaluation was completed according to guidance provided in 40 Code 

of Federal Regulations (CFR) 51, Appendix Y and the Washington, Oregon, and Idaho BART 

modeling protocol1

. 

A baseline Class I area visibility impact analysis was performed on 100 BART-eligible emission 

units at Intalco using the CALPUFF model as recommended by the modeling protocol. These 

sources include three potlines, the anode bake furnace, 12 aluminum holding furnaces, various 

material handling and transfer operations, natural gas, diesel and propane combustion sources, 

and other small miscellaneous sources. 

The modeled or projected 98th percentile visibility impacts for the entire facility exceed the 0.5 

deciview (dv) contribution threshold in five Class I areas: Alpine Lakes Wilderness Area, 

Glacier Peak Wilderness Area, Mount Rainier National Park, North Cascades National Park, and 

Olympic National Park. The highest modeled facility-wide impact is 1.527 deciviews (dv) in the 

Olympic National Park (ONP). The modeled visibility impacts are primarily from the potlines, 

with a small amount from the anode bake furnace. Other sources contribute negligible amounts 

to the total as described further below. 

The highest modeled or projected 98th percentile visibility impact of the potlines is 

approximately 1.44 dv in the ONP. The projected impacts in the other, more distant, Class I 

areas are lower. More than 98% of the projected impact from the potlines is attributable to 

emissions from the potroom primary control devices, with the remainder from the existing 

potroom roof scrubbers. More than 96% of the potroom primary control device impact is from 

emissions of sulfur dioxide (SO2). 

 

1 Modeling Protocol for Washington, Oregon, and Idaho: Protocol for the Application of the CALPUFF Modeling 

System Pursuant to the Best Available Retrofit Technology (BART) Regulation.

www.deq.state.or.us/aq/haze/docs/bartprotocol. October 11, 2006. 
Intalco BART Determination FINAL.doc - ES-2 - 

Results from the BART analysis for potroom emissions determined that BART for potline SO2

emissions is a pollution prevention limit of 3% sulfur in the calcined petroleum coke used to 

manufacture anodes (i.e., coke). BART for other pollutants emitted from the potlines 

[particulate matter (PM) and nitrogen oxides (NOx)] was determined to be the existing level of 

emission control. 

The highest modeled or projected 98th percentile visibility impact from the anode bake furnace is 

approximately 0.053 dv in ONP, with lower projected impacts in other Class I areas. More than 

40% of the anode bake furnace impact (0.02 dv) is from SO2 emissions and 55% of the impact 

(0.03 dv) is from NOx. The analysis of control options for the anode bake furnace determined 

that BART for bake furnace SO2 emissions is a pollution prevention limit of 3% sulfur in the 

coke. BART for other pollutants emitted from the anode bake furnace (NOx and PM) was 

determined to be the existing level of emission control. 

Additional BART-eligible emission units at the Intalco facility include aluminum holding 

furnaces, various material handling and transfer operations, natural gas, diesel, and propane 

combustion, and other small miscellaneous sources that support the primary aluminum ore 

reduction process. The combined projected impacts from all remaining BART-eligible emission 

units (sources other than the potlines and anode bake furnace) are less than 0.05 dv in ONP, with 

lower projected impacts in other Class I areas. Considering the minimal contribution to visibility 

impairment (less than 0.05 dv) and the existing level of emissions control, these emission sources 

were excluded from further engineering analysis and BART was determined to be no further 

emissions control for these sources. 
Intalco BART Determination FINAL.doc 1-1

1.0 INTRODUCTION 

The Clean Air Act (CAA) requires the protection of visibility in 156 scenic areas across the 

United States. Under CAA Section 169A(b)(2)(A), states must require certain existing stationary 

sources to install Best Available Retrofit Technology (BART). A “BART-eligible” source is one 

that is contained in the 26 identified source categories that has the potential to emit greater than 

or equal to 250 tons per year of any air pollutant and was put in place during the 15-year interval 

between August 7, 1962, and August 7, 1977. BART is required when any source meeting this 

definition emits any air pollutant that may reasonably be anticipated to cause or contribute to any 

impairment of visibility in any Class I area. 

 
Intalco BART Determination FINAL.doc 2-1

2.0 IDENTIFICATION OF BART-ELIGIBLE UNITS AT INTALCO 

Alcoa, Inc. – Intalco Works (Intalco) operates emission units that fall within the categories of 

primary aluminum ore reduction plants, one of the 26 identified source categories to which 

BART is applicable. The Intalco facility was originally constructed in 1965, and began 

operation in 1966. Therefore, the facility’s emission units were in existence on August 7, 1977, 

but were not in operation before August 7, 1962. The facility has the potential to emit greater 

than or equal to 250 tons/year of sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate 

matter (PM), all of which have been classified as visibility impairing pollutants. As such, the 

Intalco facility is defined as a BART-eligible source. All emission units at Intalco, with the 

exception of one remelt furnace, were constructed between August 7, 1962 and August 7, 1977 

and are, therefore, BART-eligible. 
Intalco BART Determination FINAL.doc 3-1

3.0 BART-ELIGIBLE EMISSION UNIT GROUP DESCRIPTION 

3.1 PRIMARY ALUMINUM REDUCTION PROCESS DESCRIPTION

Intalco’s primary aluminum reduction operations include three potlines, an electrode 

manufacturing operation, consisting of a paste production operation and a green anode baking 

furnace, and miscellaneous material handling operations. 

The potline operation manufactures metallic aluminum by the electrolytic reduction of alumina 

in side-worked prebake cells. Direct electrical current, passing between anodes and the cathode, 

electrolytically reduces the alumina to metallic aluminum and oxygen. Molten aluminum is 

deposited and accumulates over time at the cathode beneath a layer of molten cryolite bath. 

Periodically the molten aluminum is siphoned from beneath the cryolite bath and processed to 

achieve specific metal properties or is retained as pure aluminum. The produced aluminum is 

solidified into intermediate or final products. 

Anodes are manufactured in an ancillary on-site paste production plant. Calcined petroleum 

coke used to manufacture anodes (i.e., coke) is crushed and sized, anode butt material is crushed 

and sized, and both are mixed together with pitch and formed into self-supporting carbonaceous 

blocks called “green anodes.” The green anodes are then cured and baked in furnaces before 

being used in the side-worked prebake aluminum reduction process. 

Table 3-1 presents the individual emission units that are included in the primary aluminum 

reduction emission unit group and that were identified as BART-eligible emission units. Potlines 

A, B, and C emit SO2 and PM, and the anode bake furnace emits lesser amounts of SO2, NOx, 

and PM. These emission units are already equipped with sophisticated emission control 

equipment for PM, so the BART determination for these emission units focuses primarily on 

potential reductions for SO2 and NOx. 

The remaining emission units identified in Table 3-1 include aluminum holding furnaces, various 

material handling and transfer operations, natural gas, diesel, and propane combustion, and other 

small miscellaneous sources that support the potlines and anode bake furnace. Aside from the 

natural gas combustion products, emissions from most of the support operations consist of 

relatively small amounts of PM that are controlled by fabric filter type control devices. Fabric 

filters effectively remove more than 99% of particulate emissions and, based on the control 

technology review, represent the best available control for these types of material handling and 

transfer operations. The natural-gas fired units at Intalco emit very little PM. Given the 

relatively low level of emissions, the fact that fabric filters represent the best available control, 

and the minimal impacts of these sources on visibility, these emission units were excluded from 
Intalco BART Determination FINAL.doc 3-2

further BART engineering analysis. BART for these support operations was determined to be 

the existing level of control. 

3.1.1 Existing Potline Emissions Control 

The potlines at Intalco consist of six potroom groups [i.e., “...a group of potroom segments 

ducted to a common control system” (40 Code of Federal Regulations 60.191)] of electrolytic 

reduction cells connected in series that produce molten aluminum. There are two potroom 

groups per potline. Each potroom is comprised of 120 reduction cells (or pots) with 18 anodes 

per cell. All pots at Intalco are hooded to control emissions. Emissions captured by the hoods 

are drawn through primary control systems, which consist of dry alumina injection systems with 

baghouses for the control of PM and fluoride emissions. A small fraction of the pot emissions 

escape capture by the hoods and are released inside the potrooms. These secondary emissions 

are drawn through a secondary control system which consists of wet roof scrubbers that control 

PM and fluoride emissions. 

Each of Intalco’s primary control system centers consists of multi-compartment baghouse cells. 

Either reverse pulse or reverse flow is used in cleaning the fabric filters of the baghouse cells. 

The multiple compartment design allows for maintenance and troubleshooting of individual cells 

while the baghouse center is still operating. The PM control efficiency of the primary control 

system is estimated to be 97.7% based on measured emissions. 

Fugitive potroom emissions from primary aluminum smelters are typically not controlled. 

However, Intalco operates a secondary pollution control system on each of its potlines to abate 

fugitive emissions. The secondary control system consists of 159 wet roof scrubbers for the 

three potlines. Each wet roof scrubber treats approximately 10,000 actual cubic feet per minute 

(acfm) of potroom air. The wet roof scrubbers become inoperable and must be shutdown during 

any sustained periods of below-freezing temperatures in order to avoid permanent damage from 

freezing. These shutdowns occur only in the winter months, and occur infrequently. For the last 

four operating years, shutdowns due to cold temperatures have averaged less than six or seven 

days per year. The PM control efficiency of the secondary control system is estimated to be 

approximately 82%. 

3.1.2 Anode Bake Furnace Emissions Control 

Products of natural gas combustion, products of combustion from volatiles liberated during the 

baking of green anodes, and other emissions typically associated with anode baking are 

exhausted to a dry alumina scrubbing system. The baking furnace emission control equipment 

conditions the exhaust gases prior to alumina being injected. Fabric filtration modules located 

downstream of the alumina injection reduce PM emissions by as much as 99%. 
Intalco BART Determination FINAL.doc 3-3

3.1.3 Aluminum Holding Furnace Emissions Control 

The 12 holding furnaces at Intalco vary in size. The largest of these furnaces has a natural gas 

rated burner capacity of 22 MMBtu/hr. There are no emission controls associated with the 

aluminum furnaces at Intalco. 
Intalco BART Determination FINAL.doc 4-1

4.0 BASELINE CONDITIONS AND VISIBILITY IMPACTS FOR BARTELIGIBLE UNITS 

CALPUFF modeling was performed to evaluate the cumulative visibility impacts of BARTeligible emission units at Intalco, and to compare the relative contribution of individual emission 

units to the total visibility impact. All modeling performed in association with this BART 

determination was done by TRC Environmental Corporation following the WDOE’s BART 

modeling protocol2. The complete Intalco BART modeling report is contained in Appendix A. 

4.1 CALPUFF MODEL AND BASELINE EMISSION INPUTS

CALPUFF and its meteorological model CALMET are designed to handle the complexities 

posed by complex terrain, long source receptor distances, chemical transformation and 

deposition, and other issues related to Class I impacts. The USEPA adopted the CALPUFF 

modeling system as a guideline model for source-receptor distances greater than 50 km and for 

use on a case-by-case basis in complex flow situations for shorter distances (Federal Register, 

April 15, 2003). CALPUFF was recommended for Class I impact assessments by the Federal 

Land Managers Workgroup in 2000 and the Interagency Workgroup on Air Quality Modeling in 

1998. CALPUFF is recommended by USEPA (Federal Register, July 6, 2005) and the State of 

Washington3

 for BART analyses. 

Tables 4-1, 4-2, 4-3, and 4-4 present the baseline modeling source input data for point sources, 

line sources, area sources, and volume sources, respectively, that were used in the CALPUFF 

model to forecast the visibility impacts. In accordance with Section IV of 40 CFR 51 Appendix 

Y and the BART modeling protocol for Washington, Oregon, and Idaho, baseline emission rates 

used in the model were based on 24-hour average actual emissions from the highest emitting day. 

4.2 SCREENING-LEVEL MODELING ANALYSIS

Screening runs were performed for 2003 through 2005 using the 4-km resolution CALMET 

meteorological data set prepared by Geomatrix for Washington, Oregon, and Idaho. Eight Class 

I areas (Mount Adams Wilderness Area, North Cascades National Park, Goat Rock Wilderness 

Area, Pasayten Wilderness Area, Glacier Peak National Park, Alpine Lakes Wilderness Area, 

Olympic National Park, and Mount Rainier National Park) were included in the screening level 

visibility modeling. 

 

2 Modeling Protocol for Washington, Oregon, and Idaho: Protocol for the Application of the CALPUFF Modeling 

System Pursuant to the Best Available Retrofit Technology (BART) Regulation.

www.deq.state.or.us/aq/haze/docs/bartprotocol.pdf. October 11, 2006. 3

 Ibid. 
Intalco BART Determination FINAL.doc 4-2

The screening level analysis results are presented in Table 4-5. These results project visibility 

impacts within Mount Adams Wilderness Area of less than 0.5 dv, indicating that Intalco does 

not contribute to visibility impairment in the Mount Adams Wilderness Area. A refined, 1-km 

visibility impact analysis was subsequently performed on the remaining seven Class I areas. 

4.3 REFINED MODELING ANALYSIS

Table 4-6 presents the modeled 98th percentile total source visibility impacts (reported as 

deciviews) for 2003, 2004, and 2005 in the seven Class I areas identified in the screening 

modeling analysis as having visibility impacts greater than 0.5 dv. Refined modeled visibility 

impacts exceed the contribution threshold limit of 0.5 dv at Alpine Lakes Wilderness Area, 

Glacier Peak Wilderness Area, Mount Rainier National Park, North Cascades National Park, and 

Olympic National Park. Refined modeled visibility impacts at the Goat Rock and Pasayten 

Wilderness Areas were below the 0.5 dv contribution threshold. The highest predicted visibility 

impacts were in Olympic National Park. 

Table 4-7 presents a culpability analysis for Olympic National Park. Individual emission unit 

visibility impacts in Olympic National Park were used to identify which emission units were 

forecasted to have the most impact on visibility impairment. The modeled or projected 98th

percentile visibility impact from the combined potline emissions for the maximum year is 

approximately 1.44 dv in Olympic National Park. More than 98% of this projected impact from 

the potlines is attributable to emissions from the potroom primary control devices, with the 

remainder from the potroom wet roof scrubbers. More than 96% of the potroom primary control 

device impact is from emissions of SO2. The modeled or projected 98th percentile visibility 

impact for the maximum year from the anode bake furnace was 0.053 dv in Olympic National 

Park. More than 40% of the anode bake furnace impact is attributable to SO2 emissions and 

approximately 55% of the impact is from NOx emissions. The total projected impacts from the 

remainder of the facility’s BART-eligible sources for the maximum year are 0.049 dv in 

Olympic National Park. 

For all emission units other than the potlines and anode bake furnace, the refined modeling 

results in Table 4-7 show a combined total visibility impact that is less than 0.05 dv. The 

combined impact of these emission units is less than 10% of the facility-wide contribution 

threshold level of 0.5 dv for BART applicability established for Washington4

. Reduction in 

emissions from these units would not result in significant visibility improvement in any of the 

Class I areas. For example, the modeled visibility impact from all 12 aluminum holding furnaces 

(casthouse stacks in Table 4-7) was 0.004 dv at ONP. The use of added controls for these 

 

4 Modeling Protocol for Washington, Oregon, and Idaho: Protocol for the Application of the CALPUFF Modeling 

System Pursuant to the Best Available Retrofit Technology (BART) Regulation. October 11, 2006. 

www.deq.state.or.us/aq/haze/docs/bartprotocol.pdf 
Intalco BART Determination FINAL.doc 4-3

furnaces would provide a negligible visibility improvement at ONP, as well as the other Class I 

areas. 

Based on results from the baseline modeling, the scope of the BART control analysis and 

engineering cost calculations were focused on the potlines and anode bake furnace. 
Intalco BART Determination FINAL.doc 5-1 

5.0 BART ANALYSIS FOR BART-ELIGIBLE EMISSION UNITS 

The results of the refined CALPUFF modeling show that Intalco’s potline reactors and anode 

bake furnace contribute to visibility impairment in five Class I areas. The BART analysis 

completed for these emission sources is described in this section. The analysis included a review 

of available and technically feasible retrofit technologies (Steps 1 and 2), determination of 

control effectiveness for feasible options (Step 3), evaluation of cost and secondary impacts for 

feasible alternatives (Step 4), and analysis of impacts and visibility improvements (Step 5). 

5.1 AVAILABLE AND TECHNICALLY FEASIBLE EMISSION CONTROL OPTIONS

Steps 1 and 2 of the BART analysis are to identify available emission control options and to 

evaluate the technical feasibility of these control technologies. Control options for the potline 

reactors and anode bake furnace are described separately in the following sections. 

5.1.1 Potline Emissions and Existing Controls 

Aluminum is manufactured in large electrolytic reduction cells called pots. Aluminum is 

produced from alumina in the pot as current is passed from a carbon anode to carbon blocks on 

the pot wall, which serve as the cathode. The anodes are made from pitch and coke. The major 

pollutants emitted from the cells are PM, hydrogen fluoride, SO2, and carbon monoxide. PM 

includes particulate fluoride, carbon dust, and alumina. SO2 comes from the sulfur in the 

components used to make the anodes. NOx emissions are minimal since there is no external fuel 

or combustion zone and there are no large sources of nitrogen in the raw materials. 

Emissions from the pots are collected by close capture hoods over each pot. The hoods enclose 

the pot as tightly as possible to collect off-gases, but sections may be removed to allow anodes to 

be changed. The off-gases are collected into manifolds that combine the gases from the 

individual pots. The temperature of the exhaust gases entering the control equipment is typically 

150 to 300°F5

. The combined gases are routed to a dry alumina scrubber. The potline primary 

control systems for Intalco's three potlines consist of dry scrubbers using alumina injection with 

fabric filtration for PM control. The system at Intalco is large, treating approximately 1,815,000 

acfm of 180°F exhaust gases. 

5.1.2 Anode Bake Furnace Emissions and Existing Controls 

The anode bake furnace structure is a series of interconnected refractory flues connected to side 

main exhaust manifolds. The furnace is fueled with natural gas. Exhaust gases are routed so that 

 

5

 Air and Waste Management Association (AWMA). 2000. Air Pollution Engineering Manual, Second Edition. 
Intalco BART Determination FINAL.doc 5-2 

flue gases preheat the next section to be fired. Flue gases from the anode bake furnace contain 

PM, hydrogen fluoride, SO2, carbon monoxide, and hydrocarbons. 

The bake furnace control device used at Intalco is similar to the potline primary control system, 

consisting of dry alumina injection with fabric filtration. The bake oven gas stream is 

conditioned by a water spray to reduce the inlet temperature before it enters the scrubber. Fresh 

and recycled alumina are injected into the gas stream, gaseous fluoride and POM are adsorbed 

onto the alumina surface, and fabric filters on top of the reactor compartments collect entrained 

particulate matter present in the gas stream. The system at Intalco treats approximately 216,000 

acfm of 205°F exhaust gases. 

5.1.3 Potentially Applicable BART Control Options for SO2

Sulfur in the anodes is oxidized, releasing SO2 from the potlines as the anodes are consumed. 

SO2 is also released from the anode bake furnace as pitch used to help form the anodes is 

oxidized during the baking process. Options for controlling SO2 include both add-on controls 

and pollution prevention. 

5.1.3.1 Add-on Emission Controls 

Absorption and adsorption have been used for the control of SO2 emissions from 

numerous power utility and industrial processes. As a result many commercialized 

control technologies have been used for SO2 control. However, the practical application 

of these controls systems to the potline reactors and anode bake furnace is limited by the 

very low inlet SO2 levels, in the range of 100 parts per million by volume (ppmv), and 

the expected range of gas conditions, including temperature, oxygen content, humidity, 

SO2/O2 ratio, and gas impurities. 

Eight different SO2 control options were considered as having potential practical 

application as part of the BART analysis. Two of these technologies have been applied 

to the control of SO2 emissions at aluminum smelters. Six of the control options use wet 

scrubbing and two use dry scrubbing technology. The eight potentially applicable control 

options are: 

• Limestone slurry scrubbing with forced oxidation 

• Limestone slurry scrubbing with natural oxidation 

• Conventional lime wet scrubbing 

• Seawater scrubbing 

• Dual alkali sodium/lime scrubbing (dilute mode) 

• Conventional sodium scrubbing 
Intalco BART Determination FINAL.doc 5-3 

• Dry injection 

• Semi-dry scrubbing 

5.1.3.1.1 Wet Scrubbing 

The primary development of SO2 control technology occurred because of the need to 

control emissions from the coal-fired, electric utility power industry6. The large 

volumetric size of the potroom exhaust (approximately 1,815,000 acfm) would 

require a system similar to those used in the electric utility power industry. 

The typical temperature range for wet scrubbers is 300 to 700°F. For utility 

combustion units, wet scrubbing systems have been installed on systems as large as 

1,500 megawatts (MW). Sodium compounds, lime, or limestone can be used. 

However, the high solubility of sodium complicates disposal of waste and 

wastewater. The typical sorbent material is lime or limestone. Lime is generally 

easier to manage on-site but is significantly more costly. Wet limestone scrubbing 

has a high capital and operating cost due to the handling of liquid reagent and waste, 

but is the preferred process for coal-fired utility power plants due to the low cost of 

limestone and high removal efficiencies. Typical removal efficiencies for wet 

scrubbers are between 80 and 95%. Approximately 85% of the flue gas 

desulfurization (FGD) systems installed in the United States are wet scrubber 

systems7. 

In wet scrubbers, the waste gas enters a large vessel (spray tower or absorber), where 

it is sprayed with water slurry. The calcium in the slurry reacts with SO2 to form 

CaSO3. A portion of the slurry from the reaction tank is pumped into the thickener, 

where the solids settle before going to a filter for final dewatering to about 50% 

solids. Figure 5-1 is a simplified process flow diagram of a conventional wet 

scrubber. 

 

6

 AWMA. 2000. Air Pollution Engineering Manual, Second Edition. 7

 USEPA. 2003. “Air Pollution Control Technology Fact Sheet – Flue Gas Desulfurization.” EPA-452/F-03-034. 

August 8. 
Intalco BART Determination FINAL.doc 5-4 

Figure 5-1. Wet scrubber process flow diagram 

Inlet

Gas

Particulate Control

Clean gas out

Spray tower/absorber

Fly Ash

Lime (stone)

and Water

Reaction

Tank

Calcium-based

sorbent spray

Thickener

Filter

Solids

Stabilized Waste

Lime

Blending

Pugmill

Reagent

Supply

Liquid Waste

Stream

In the utility industry, the CaSO3 waste product is usually mixed with fly ash 

(approximately 1:1) and fixative lime (approximately 5%) and typically disposed of 

in landfills. Alternately, the forced oxidation process oxidizes the spent slurry to 

gypsum. Gypsum crystals dewater more efficiently and reduce the size of waste 

handling equipment. Depending on quality and demand, the gypsum may be 

commercially sold, eliminating the need for landfilling the waste product. 

“Mist eliminators” installed at the spray tower outlet or downstream ductwork 

remove droplets from the gas. In some power plant installations, the gas is reheated 

to avoid corrosion downstream. Many scrubbers have gas bypassing capability, 

which can be used for gas reheating. If the wet scrubber is downstream of a highefficiency particulate removal device [fabric filter or electrostatic precipitator (ESP)], 

the particulate concentration may be higher leaving the scrubber than entering due to 

the solids in mist droplets that are carried out of the scrubber. 
Intalco BART Determination FINAL.doc 5-5 

Some disadvantages of using wet scrubbing techniques in many applications are the 

requirement to treat wastewater, the need to construct components from expensive 

alloys to resist corrosion, and much higher energy usage. A practical issue associated 

with a wet scrubber system is the complexity of the system. The space required for a 

wet system is substantial (i.e., large footprint), the systems require more maintenance 

due to their complexity, and more personnel are required for their operation. 

5.1.3.1.1.1 Limestone Slurry Forced Oxidation 

Limestone slurry forced oxidation (LSFO) is used extensively in the utility FGD 

market. The raw material is finely ground limestone. There are a number of 

suppliers of LSFO technology. The most commonly used equipment is an open, 

multi-level, countercurrent spray tower scrubber equipped with spray nozzles to 

inject the limestone slurry droplets into the gas stream. Liquor is collected at the 

bottom of the tower and sparged with air to oxidize the calcium sulfite to calcium 

sulfate to enhance the settling properties of the calcium sulfate. Recirculation 

pumps circulate the scrubbing liquor to the spray nozzles. SO2 removal 

efficiencies of 90% have been achieved. The bleed from the scrubber is sent to a 

dewatering system to remove excess moisture. For an aluminum smelter, the 

process will produce either solid gypsum waste or commercial-grade gypsum 

suitable for reuse as a cement additive if a cement production facility is available 

and willing to accept the material. Only a very small purge or blowdown stream 

is required. 

LSFO was determined to be a technically feasible retrofit control option for the 

potroom reactor and the anode baking exhausts even though it is not ideally suited 

for scrubbing SO2 concentrations that are less than or equal to 105 ppm. 

5.1.3.1.1.2 Limestone Slurry Natural Oxidation 

Limestone slurry natural oxidation (LSNO) is very similar to LSFO. The major 

difference is the absence of an oxidation stage. The gypsum/calcium sulfite 

product is essentially a waste product with limited possibilities of use for 

agricultural purposes. 

5.1.3.1.1.3 Conventional Lime Wet Scrubbing 

Conventional lime wet scrubbing is also similar to LSFO except that the raw 

material is hydrated lime or quick lime that is either slaked on-site or purchased in 

the slaked form. The system typically uses forced oxidation, although natural 

oxidation is possible. The process will produce either solid gypsum waste or 
Intalco BART Determination FINAL.doc 5-6 

commercial-grade gypsum suitable for reuse as a cement additive if a cement 

production facility is available and willing to accept the material. 

5.1.3.1.1.4 Seawater Scrubbing 

Seawater scrubbing is a method for controlling SO2 emissions in which seawater 

is used to absorb SO2 in exhaust gases. Seawater is slightly alkaline (with a pH of 

approximately 8). SO2 has a high solubility in seawater. Absorbed SO2 is 

subsequently oxidized to sulfates by the use of aeration and the pH is adjusted by 

the addition of additional seawater. 

There are three main steps in this process: absorption, oxidation, and 

neutralization. Seawater is passed countercurrent through the gaseous exhaust 

stream, typically using a spray column in the aluminum industry. SO2

preferentially dissolves in the seawater. Removal efficiencies of 85% to 95% 

have been measured in practice. The clean exhaust gas is de-misted prior to 

release to the atmosphere. The acidified seawater is then passed to an oxidation 

basin in which air is blown through the effluent. The additional oxygen ensures 

that the dissolved SO2 is converted to sulfates. Finally, additional fresh seawater 

is added to adjust the pH back up to neutral (or slightly alkaline) and the seawater 

is discharged back into the ocean. 

The effluent from this process will typically have a temperature increase of about 

1°C and will have a change in sulfate concentration of approximately 2-5% above 

background8,9. Scrubbing of the potline emissions also adds fluoride and trace 

amounts of polycyclic aromatic hydrocarbons (PAHs) to the effluent seawater. 

No additional chemicals are required and there is normally no solid waste 

generated for disposal as the effluent is typically discharged directly to the sea. 

The pH of the effluent can be adjusted to within the original range in the 

neutralization step of the process. 

The volume of seawater required varies with exhaust flowrate and SO2 loading in 

the gaseous exhaust stream. Based on a review of specifications for existing 

potline seawater scrubbing systems, the volumetric flowrate of seawater needed 

for proper operation of a seawater scrubber at Intalco would be approximately 2.2 

million gallons of seawater per hour. 

 

8

 Information from the ALSTOM Seawater FGD – Environmental Impact website 

(www.environment.power.alstom.com/home/power/seawater_fgd/environmental_impact.htm) 9

 Kwawaji, Akili D., et. al. 2005. “Seawater Scrubbing for the Removal of Sulfur Dioxide in a Steam Turbine 

Power Plant”. Proceeding of the PWR2005 ASME Power Conference. April 5-7. Chicago, IL. 
Intalco BART Determination FINAL.doc 5-7 

A global review of feasible control technologies identified seawater scrubbing as 

having been installed at seven aluminum smelters, none of which are in the 

United States10. Even though this technology has been identified as a control 

technology in operation at six primary aluminum ore reduction plants in Norway 

and one primary aluminum ore reduction plant in Sweden11, there are two reasons 

why this technology is not feasible at Intalco. 

1) The Administrator of USEPA has issued environmental regulations 

establishing effluent limitations guidelines (ELGs) pursuant to section 304(b) of 

the Clean Water Act for facilities producing primary metals from ore concentrates 

and recovering secondary metals from recycled wastes. The ELGs are for 

facilities that discharge or may discharge pollutants to waters of the United States 

or which introduce or may introduce pollutants into a publicly owned treatment 

works. Seawater scrubbers installed to abate SO2 and other visibility impairing 

pollutants from the Intalco’s BART eligible potline emission units would be 

subject to the ELGs for “Potline SO2 Emissions Wet Air Pollution Control.”12 A 

seawater scrubber installed downstream of the alumina dry scrubbers at Intalco 

would remove both fluoride and SO2 from the dry scrubber exhaust. The amount 

of fluoride absorbed into the seawater would exceed the ELG, requiring treatment 

of the seawater to remove fluoride before it could be discharged back into the sea. 

For example with three potlines operational, approximately 159 lb/day of fluoride 

would be absorbed by the seawater and the applicable ELG would be 59.5 lb/day 

(monthly average). Removal of potline fluoride from the seawater scrubber 

effluent may be feasible, but would also require precipitation of many other 

naturally occurring salts in the seawater (chlorides, sulfates, other fluorides, etc.), 

resulting in the unnecessary generation of large amounts of sludge for land 

disposal. Seawater scrubbing is, therefore, not a viable alternative for smelters in 

the United States, especially when compared with other scrubbing technologies 

that use fresh water and require treatment/disposal for only those salts present in 

the potline exhaust. 

2) In addition to the regulatory restrictions and economic viability issues 

discussed above, a seawater scrubber is infeasible for BART compliance due to 

permitting obstacles. The Washington State Environmental Policy Act (SEPA), 

Chapter 43.21C RCW was enacted in 1971, and it provides the framework for 

agencies to consider the environmental consequences of a proposal before taking 

 

10 The HATCH Group. 2006. “Analysis of Options for BART Compliance”. April 18. Page 4. 11 Ibid. Page 9. 

12 40 CFR 421.23(n) 
Intalco BART Determination FINAL.doc 5-8 

action. It also gives agencies the ability to condition or deny proposals due to 

adverse impacts identified as likely to occur as a result of a proposal. The portion 

of Puget Sound where seawater would be withdrawn and discharged for an Intalco 

seawater scrubber has been included as part of the Cherry Point Aquatic Reserve 

that was established in 2000. The Aquatic Reserves Program is part of the 

Washington Department of Natural Resources (DNR) efforts to promote 

preservation, restoration, and enhancement of state-owned aquatic sites that 

benefit the health of native aquatic habitat and species in the state. The aquatic 

reserves established by DNR are aquatic lands of special educational or scientific 

interest, or lands of special environmental importance. The construction of intake 

and/or discharge structures within the Cherry Point Aquatic Reserve would 

require an impact analysis, assessment, and DNR authorization of any 

environmental impacts associated with a seawater scrubbing system. Since seven 

years have already passed since Cherry Point was designated as an aquatic reserve 

and the initial SEPA evaluation has yet to be completed, the time required to 

complete an analysis of the environmental impacts associated with a seawater 

scrubbing system and obtain the requisite authorizations for a system that 

withdraws seawater from and discharges scrubber liquor into the Cherry Point 

Aquatic Reserve would render this technology infeasible for BART compliance. 

5.1.3.1.1.5 Dual Alkali Sodium/Lime Scrubbing (Dilute Mode) 

Dual alkali sodium/lime scrubbing (dilute mode) uses a caustic sodium solution in 

the scrubber tower. A portion of the scrubbing liquid is discharged to a 

neutralization stage where lime slurry is used to regenerate the caustic, which is 

returned to the scrubber. The bleed from the scrubber is sent to a dewatering 

system to produce a gypsum byproduct. The process will produce either solid 

gypsum waste or commercial-grade gypsum suitable for reuse as a cement 

additive. It should be noted, however, that dual alkali sodium/lime scrubbing 

(dilute mode) is not currently marketed by major FGD vendors because the 

system is too complicated and expensive. 

5.1.3.1.1.6 Conventional Sodium Scrubbing 

Globally, conventional sodium scrubbing has been installed in at least 12 

aluminum smelters. An alkaline solution of either soda ash or sodium hydroxide 

is pumped into the scrubbing tower and recirculated through a network of spray 

nozzles. Atomized droplets contact the up-flowing gas containing SO2. Where 

this technology has been deployed, the liquid effluent containing dissolved salts, 

including sodium and fluorides, has been discharged into a large receiving stream 

or an open body of water without treatment. 
Intalco BART Determination FINAL.doc 5-9 

5.1.3.1.2 Dry Scrubbing 

5.1.3.1.2.1 Dry Injection 

In dry injection, a reactive alkaline powder is injected into a furnace, ductwork, or 

a dry reactor. Typical removal efficiencies with calcium adsorbents are 50 to 

60% and up to 80% with sodium base adsorbents. However, as with wet 

scrubbing, disposal of waste using sodium adsorbents must consider their high 

solubility in water compared to those from calcium adsorbents. The temperature 

range over which scrubbing has been used is 300 to 1,800°F; the minimum 

temperature is 300 to 350°F. Dry systems are rarely used and according to 

USEPA only 3% of FGD systems installed in the United States are dry systems13. 

The dry waste material is removed using particulate control devices such a fabric 

filter or an ESP. 

Dry scrubbing downstream of the potline reactors and anode bake furnace fabric 

filters is not technically feasible because of the low temperatures (less than or 

equal to 205°F) and low SO2 concentrations (less than or equal to 105 ppm). 

5.1.3.1.2.2 Semi-Dry Scrubbing (Spray Dryer) 

Semi-dry scrubbing is more commonly referred to as spray drying. Calcium 

hydroxide slurry (lime mixed with water) is introduced into a spray dryer tower. 

Sodium compounds can be used, but as with the dry scrubber, the high solubility 

of the sodium-based waste products in water complicates disposal of the waste. 

The slurry is atomized and injected into a reactor with the exhaust gases, where 

droplets react with SO2 as the liquid evaporates. This system is categorized as a 

semi-dry system because the end product of the SO2 conversion reaction is a dry 

material. The dry waste product is collected in the bottom of the spray dryer 

reactor and a fabric filter or ESP downstream of the spray dryer removes the 

CaSO3, CaSO4, and unreacted lime. This air pollution control system uses water 

for evaporative cooling and for the SO2 reaction. It operates in a temperature 

range of 300 to 350°F because the temperature of the gases must be high enough 

to evaporate the water portion of the slurry. Approximately 12% of the FGD 

systems installed in the United States are spray dry systems14 with typical SO2

removal efficiencies in the range of 80 to 90%. Unlike a wet scrubbing system 

there is no liquid blow-down stream from the dry system and the collected solids 

are typically landfilled. 

 

13 USEPA. 2003. “Air Pollution Control Technology Fact Sheet – Flue Gas Desulfurization.” EPA-452/F-03-034. 

August 8. 14 Ibid. 
Intalco BART Determination FINAL.doc 5-10 

Spray dry scrubbing downstream of the potline reactors and anode bake furnace 

fabric filters is not technically feasible because of the low temperatures (less than 

or equal to 205°F) and low SO2 concentrations (less than or equal to 105 ppm). 

5.1.3.2 Pollution Prevention 

The guidelines for BART determinations under the Regional Haze Rule recommend 

consideration of pollution prevention options in addition to add-on controls. The primary 

opportunity for pollution prevention in the smelting process to minimize SO2 emissions is 

through limitations on the sulfur content in the incoming coke. Coke is a major raw 

material used in the manufacture of green anodes. Green anodes are subsequently baked 

in a furnace prior to their use in the smelting process. 

Intalco’s Title V operating permit currently has a number of operational limits that cap 

allowable emissions of SO2 from the facility, including: a net potline aluminum 

production limit of 307,000 ton/yr; a daily potline SO2 limit of 37,780 pounds per day 

(lb/day); limits on sulfur in coke and pitch at 3.0% and 0.6%, respectively; and a carbon 

consumption limit of 0.425 pounds of carbon per pound of aluminum produced. 

During the BART process, Intalco evaluated the current levels of sulfur in coke used by 

other aluminum smelters to determine whether a pollution prevention option using lower 

sulfur content coke would be a feasible BART option. This analysis indicated that 

certain smelters currently utilize coke with sulfur contents as low as 2%. Given that 

sulfur contents lower than the current Intalco specification are utilized, Intalco undertook 

a low sulfur coke availability analysis to determine whether coke at levels below 3% 

would be available beyond 2013 when BART controls requirements are anticipated. 

Confidential research information belonging to the market analysts assisting with the 

coke availability analysis is included in Appendix B. The primary conclusions from this 

analysis indicate that: 

• Coke is a byproduct of the oil refining process. The sulfur content of the world’s 

crude oil supply has been and will continue increasing in sulfur content. Those 

refiners with coking capacity are minimizing their raw material costs by 

maximizing use of high sulfur crude oils and oil sands to the optimal extent for 

their overall refinery design. The result will be a continuing increase in the sulfur 

content of available coke. 

• Coke is a relatively small, low revenue component of the refinery’s product 

profile. As such, the aluminum industry has little influence in controlling the 

quantity, quality, and price of the coke produced by refineries. 
Intalco BART Determination FINAL.doc 5-11 

• Anode grade (or anode quality) coke is a small subset of the total coke produced 

world-wide. Growth in the aluminum industry has increased the demand for the 

limited quantities of anode grade coke and has driven prices for coke to 

unprecedented levels. Refining higher sulfur crude oils and oil sands further 

shrinks this small subset of anode grade coke. 

• Prices for coke nearly doubled from 1994 to 2006. 

• The increased global growth in aluminum production will continue to outpace the 

production of coke. 

• Primary aluminum production is expected to grow at the rate of 3 to 4% annually, 

resulting in a commensurate growth in demand for anode grade coke. 

• Coke providers are blending imported, high cost, lower sulfur coke with 

domestically sourced coke in attempts to meet the current specification 

requirements for coke. 

• Removal or reduction of the sulfur content of the coke once it has been received is 

not feasible. 

• Aluminum smelters are experimenting with alternative cokes and technologies 

that are outside of the traditional specifications to ensure continued aluminum 

production in the face of the changing characteristics of this key raw material. 

• The deterioration in coke quality and the tightness of supply is expected to 

continue for the foreseeable future. 

• The increased demand for coke will force the aluminum industry to accept lower 

quality coke with higher sulfur contents. 

Based on the market and availability analysis of the future coke supply, Intalco 

determined that it is infeasible to consider coke at sulfur contents below 3% as a BART 

pollution prevention option because a supply of coke with sulfur contents below 3% 

cannot be ensured beyond 2013 when BART control requirements are anticipated. These 

same market pressures are expected to force facilities currently using coke with sulfur 

contents below 3% to begin using higher sulfur content coke in the future. Although 

coke at sulfur contents below 3% is considered infeasible due to availability concerns, a 

pollution prevention option that maintains Intalco’s current sulfur in coke limit of 3% is 

considered technically viable or feasible, assuming that sufficient imported lower sulfur 

coke remains available to allow blending to 3% sulfur content beyond 2013. 
Intalco BART Determination FINAL.doc 5-12 

5.1.3.3 Feasible Control Options from RBLC Database 

A review of USEPA’s RACT/BACT/LAER Clearinghouse (RBLC) database was also 

completed to determine which control technologies or techniques have been utilized by 

primary aluminum ore reduction plants. The results from the RBLC database search are 

summarized in Table 5-1. 

The data in the RBLC database support the approach of limiting raw material sulfur 

content as a control option for the potlines and the anode bake furnace. Many facilities 

have limited sulfur content in coke to limit SO2 emissions. Two facilities have limits of 

3% sulfur content in coke and one has a 2.95% sulfur content limit. One facility is shown 

in the RBLC to have a wet scrubber to control SO2 emissions; however, an investigation 

revealed that the wet scrubber was not required as part of a best available control 

technology (BACT) determination and that the facility currently does not operate a wet 

scrubber to control SO2 emissions. That facility’s current Title V permit for “Potline 5” 

simply limits coke sulfur content to 3% and coal tar pitch sulfur to 0.8%. 

Dry alumina scrubbers (with fabric filters) are the controls that have been considered 

BACT for PM.

5.1.4 Potentially Applicable BART Control Options for PM 

Potentially applicable PM emission controls are discussed in the following sections. 

5.1.4.1 Fabric Filters 

Fabric filters generally provide high collection efficiencies for both coarse and fine 

(submicron) particles. They are relatively insensitive to fluctuations in gas stream 

conditions. Efficiency is relatively unaffected by large changes in inlet dust loadings. Filter 

outlet air is very clean15. Collected material is dry, which usually simplifies processing or 

disposal. Fabric filters are currently applied for controlling PM emissions from the 

potrooms and the anode bake furnace at Intalco. 

5.1.4.2 Electrostatic Precipitators 

ESPs are capable of very high removal efficiencies for large and small particles16. They 

offer control efficiencies that are comparable to fabric filters. Because of their modular 

design, ESPs, like fabric filters, can be applied to a wide range of system sizes. The 

operating parameters that influence ESP performance include fly ash mass loading, 

particle size distribution, fly ash electrical resistivity, and precipitator voltage and current. 

 

15 USEPA. 2003. “Air Pollution Control Technology Fact Sheet – Fabric Filter.” EPA-452/F-03-025. August 7. 16 USEPA. 2003. “Air Pollution Control Technology Fact Sheet – Dry Electrostatic Precipitator.” EPA-452/F-03-

028. August 7. 
Intalco BART Determination FINAL.doc 5-13 

Dusts with high resistivities are not well-suited for collection in dry ESPs because the 

particles are not easily charged. This also affects the ash layers on the collecting 

electrodes. An ESP is technically feasible for control of PM from the potrooms and the 

anode bake furnace at Intalco. 

5.1.4.3 Cyclones, Inertial Separators, and Wet Scrubbers 

Cyclones and inertial separators are used for collection of medium-sized and coarse 

particles. Wet scrubbers generally remove large particles but can remove small particles 

with the use of high pressure drops. However, none of these devices are as effective at 

removing small and submicron particles as fabric filters and ESPs17. 

5.1.5 Potentially Applicable BART Control Options for NOx

Potentially applicable NOx emission controls include combustion controls and post-combustion 

controls. 

5.1.5.1 Combustion Controls 

The concentration of NOx in the potroom reactor exhaust is extremely low (less than 1 

ppm) because there is no external fuel or combustion zone and there are no large sources 

of nitrogen in the raw materials. Traditional methods of preventing NOx formation using 

staged combustion or low NOx burners are not applicable to the potlines at Intalco. 

NOx emissions from anode baking depend on operating practices and burner controls. 

The traditional methods of preventing NOx formation using staged combustion or low 

NOx burners are not applicable because of the unique configuration of an anode baking 

ring furnace, with fuel injected at several points in narrow flues. However, advanced 

firing systems that measure and regulate fuel flow precisely using a computerized control 

system may reduce NOx emissions by reducing total fuel usage. Prevention of NOx

formation using advanced firing control is technically feasible for the anode bake furnace 

at Intalco. 

5.1.5.2 Post-Combustion Controls 

Selective non-catalytic reduction (SNCR), selective catalytic reduction (SCR), and low 

temperature oxidation (LoTOx) controls are discussed in this section. 

5.1.5.2.1 Selective Non-Catalytic Reduction 

SNCR is an add-on technique that involves injecting ammonia or urea into a specific 

temperature zone in a furnace or boiler. The ammonia or urea reacts with NOx in the gas 

to produce nitrogen and water. SNCR typically provides a NOx reduction of 30 to 50%. 
Intalco BART Determination FINAL.doc 5-14 

The effectiveness of SNCR depends on the temperature where reagents are injected, 

mixing of the reagent in the gas, residence time of the reagent within the required 

temperature window, and the ratio of reagent to NOx. The required temperature window 

is 1,600 to 2,100°F. Typical uncontrolled NOx levels where this technology has been 

applied vary from 200 to 400 ppm. SNCR is less effective at lower levels of uncontrolled 

NOx

18. 

The temperature (approximately 200°F) and NOx concentration (less than 1 ppm) of the 

potroom emission exhaust are outside the levels where SNCR could be used. Thus, 

SNCR is not technically feasible for the potlines at Intalco. 

The temperature of the anode baking emission exhaust (300 to 450°F) is below the 

temperature where SNCR could be used. Downstream of the reactor where tar vapors are 

removed, the temperature is approximately 200°F, which is also below the appropriate 

range. In addition, the NOx concentration (less than 20 ppm) is below the level where 

SNCR could be used. Thus, SNCR is not technically feasible for the anode bake furnace 

at Intalco. 

5.1.5.2.2 Selective Catalytic Reduction 

SCR is an add-on technique similar to SNCR that involves injecting ammonia into flue 

gas in the presence of a metal-based catalyst to convert NOx emissions to elemental 

nitrogen and water. The catalyst allows SCR systems to operate at much lower 

temperatures than SNCR; typical temperatures for SCR are 500 to 800°F, compared with 

1,600 to 2,100°F for SNCR. The optimum temperature range is 700 to 750°F19. SCR is 

capable of NOx reduction efficiencies in the range of 70 to 90% and can be used with 

NOx concentrations as low as 20 ppm. However, higher NOx levels result in increased 

performance20. 

The temperature of the potroom emission exhaust (approximately 200°F) and NOx

concentration (less than 1 ppm) of the potroom emission exhaust are outside the levels 

where SCR could be used. Thus, SCR is not technically feasible for the potlines at 

Intalco. 

The temperature of the anode baking emission exhaust (300 to 450°F) is below the 

temperature where SCR could be used. Downstream of the reactor where tar vapors are 

 17 AWMA. 2000. Air Pollution Engineering Manual, Second Edition. 18 USEPA. 2003. “Air Pollution Control Technology Fact Sheet – Selective Non-Catalytic Reduction.” EPA452/F-03-031. August 8. 

19 USEPA. 2002. EPA Air Pollution Control Cost Manual, Sixth Edition. EPA/452/B-02-001. January. 20 USEPA. 2003. “Air Pollution Control Technology Fact Sheet – Selective Catalytic Reduction.” EPA-452/F-03-

032. August 8. 
Intalco BART Determination FINAL.doc 5-15 

removed, the temperature is approximately 200°F, which is also below the appropriate 

range. In addition, the NOx concentration (less than 20 ppm) is below the level where 

SCR could be used. Thus, SCR is not technically feasible for the anode bake furnace at 

Intalco. 

5.1.5.2.3 Low-temperature Oxidation Technology (LoTOxTM) 

The LoTOxTM system is the patented technology of BOC Gases. In this NOx removal 

system, ozone is injected into the exhaust gas stream in order to oxidize insoluble NOx to 

soluble nitrogen compounds, including N2O5. N2O5 is highly soluble and reacts with 

moisture in the gas stream to form nitric acid. A scrubber is required downstream of the 

LoTOxTM system to remove the nitric acid formed by the reaction of N2O5 and moisture 

in the gas stream. The ozone is typically generated on site and on demand. Since 

LoTOxTM is a low temperature system it does not require heat input and the low operating 

temperature (150 to 250°F) allows for stable and consistent control even with variations 

in flow, load, and NOx concentrations21. 

Use of the LoTOxTM system has not been demonstrated at an aluminum plant. Research 

indicates that application of the LoTOxTM technology has been limited to a sulfuric acid 

regeneration plant, a lead smelting reverbatory furnace, a stainless steel plant, a coal-fired 

electric generation unit, and two fluidized-bed catalytic cracking units (FCCU) at 

refineries22,23. Reported NOx removal efficiencies for the LoTOxTM system are on the 

order of 90% to 95%. 

The temperature of the anode baking emission exhaust (approximately 200°F) is within 

the temperature range where LoTOxTM could be used. Although this technology has not 

been demonstrated on an anode bake furnace, low-temperature oxidation technology may 

be technically feasible for reducing anode bake furnace NOx emissions. 

5.1.6 Summary of Technically Feasible BART Control Options 

5.1.6.1 Feasible BART Control Options for SO2

Two technically feasible options were identified for controlling SO2 emissions from the 

potlines and anode bake furnace: 

• Adding a wet scrubber to the potline and/or anode bake furnace exhausts, and 

 

21 BOC Process Gas Solutions. 2001. Low Temperature Oxidation System Demonstration at RSR Quemetco, Inc., 

City of Industry, California. June 28. (www.arb.ca.gov/research/icat/projects/boc.pdf) 22 USEPA. 2005. “Using Non-Thermal Plasma to Control Air Pollutants”. EPA-456/R-05-001. February. 

www.epa.gov/ttn/catc/dir1/fnonthrm.pdf, 23 USEPA RACT/BACT/LAER Clearinghouse (RBLC) database. 
Intalco BART Determination FINAL.doc 5-16 

• A pollution prevention option limiting the sulfur content in the coke used to 

produce anodes to 3.0%. 

These two options were evaluated further as part of the BART determination analysis. 

5.1.6.2 Feasible BART Control Options for PM 

Cyclones, inertial separators, wet scrubbers, ESPs, and fabric filters are all technically 

feasible for controlling potroom PM emissions. However, ESPs and fabric filters are 

superior devices for controlling fine PM. 

Fabric filtration with dry alumina scrubbing has been widely used in the primary 

aluminum industry. Most smelters constructed within the past 20 years have used dry 

alumina scrubbing with fabric filters to control emissions from potlines. A few plants use 

control systems consisting of ESPs to collect PM followed by spray towers to scrub 

gaseous fluoride. Wet systems have many disadvantages, such as corrosion by 

hydrofluoric acid, scaling, and the requirement to treat wastewater. ESPs and wet 

systems are no longer installed on new smelters24. 

Dry scrubbers are widely used on anode bake furnaces because they provide effective 

removal of hydrocarbons, fluorides, and PM. Wet systems have the same disadvantages 

for anode bake furnaces as for potlines: corrosion by hydrofluoric acid, scaling, and the 

requirement to treat wastewater. Dry scrubbers with fabric filters are a superior choice 

for anode bake furnaces. 

Given that fabric filters are already used for PM control and that these high-efficiency 

devices are superior or equal to other feasible control options, no further analysis of PM 

controls was performed. 

5.1.6.3 Feasible BART Control Options for NOx

Since there is no external fuel or combustion zone in the smelting cells, there are no 

technically feasible pre-combustion NOx controls. Likewise, there are no technically 

feasible add-on controls because of the temperature of the potroom exhaust 

(approximately 200°F) and low NOx concentration (less than 1 ppm). 

Advanced firing systems may prevent NOx formation by reducing natural gas usage and 

are technically feasible for the anode bake furnace. Add-on SCR and SNCR controls are 

not feasible at the furnace exhaust because of the temperature (less than 450°F) and 

presence of tar vapor. SCR and SNCR are not feasible downstream of the reactor 

because of the temperature (approximately 200°F) and low NOx concentration (less than 

 

24 Air and Waste Management Association (AWMA). 2000. Air Pollution Engineering Manual, Second Edition. 
Intalco BART Determination FINAL.doc 5-17 

20 ppm). The use of low temperature oxidation (LoTOxTM) may be a viable option for 

reducing NOx emissions if a wet scrubber were installed on the bake furnace for SO2

control. 

The option for reducing NOx formation through advanced firing systems for the anode 

bake furnace was evaluated further as part of the BART determination analysis. Further 

consideration was also given to the potential use of low temperature oxidation 

(LoTOxTM). 

5.2 CONTROL EFFECTIVENESS OF FEASIBLE OPTIONS

Step 3 of the BART analysis is to evaluate the control effectiveness of the technically feasible 

control technologies. 

5.2.1 SO2 Wet Scrubbing 

A wet scrubber was identified as a technically feasible add-on pollution control option to 

reduce SO2 from the potline reactors. Typical removal efficiencies are 80 to 95%. 

Capital cost estimates and control efficiencies for wet scrubbers at Intalco were 

developed by scaling costs from two vendor quotes obtained for the installation of LSFO 

scrubbing technology at Alcoa’s facility in Alcoa, Tennessee. Each of the vendors that 

provided proposals for the Tennessee facility indicated that a 95% SO2 removal was 

technically feasible. Accordingly, an SO2 removal efficiency of 95% was used in the 

Intalco BART analysis for the wet scrubber control option. 

Mist droplets will be a component of the gas stream emitted from the scrubber. Solids in 

the droplets will become airborne PM when the water in the droplets evaporates. The PM 

concentration in the outlet of the wet scrubber was predicted to be 20 mg/Nm3 by one of 

the vendors. This compares to a concentration of 10 mg/Nm3

 currently emitted from the 

existing potline control system. Consequently, the wet scrubber option would cause a 

collateral increase in PM from the potlines. 

A wet scrubber was also identified as a technically feasible add-on pollution control 

option for the anode bake furnace since it has an SO2 concentration and a temperature 

similar to the potline reactor exhaust. However, the anode bake furnace is a smaller 

source than the potlines because of the lower exhaust gas flow rate (1,950,000 acfm 

versus 202,500 acfm). A separate vendor cost proposal was not obtained for the anode 

bake furnace, but an SO2 removal efficiency of 95% is assumed to be feasible. Wet 

scrubber costs for the anode bake furnace were also scaled from the LSFO potline wet 

scrubber vendor quotes. 
Intalco BART Determination FINAL.doc 5-18 

Table 5-2 summarizes the SO2, NOx, and PM emission levels under the control scenarios 

considered for BART. The emissions represent the combined total emissions from the 

primary and secondary potline control systems and the anode bake furnace for each 

scenario. Control scenario #1 is the addition of a wet scrubber to the potline reactors. 

Control scenario #2 is the addition of a wet scrubber to the anode bake furnace. The 

current potential emissions with 3.0% sulfur coke are also listed. The emissions 

reductions achievable for each of the scenarios were compared to current potential 

emissions. 

5.2.2 SO2 Pollution Prevention 

The pollution prevention option represents a 3.0% sulfur limit in the coke used to produce 

anodes. This option reflects the current sulfur limit in Intalco’s Title V operating permit. 

5.2.3 Anode Bake Furnace Advanced Firing System 

NOx emissions from the anode bake furnace could be reduced by incorporating an advanced 

firing system. Total gas usage is projected to be reduced by 20%, which would result in a 

corresponding 20% reduction in NOx emissions, or approximately 27 tons/year. 

5.2.4 Anode Bake Furnace LoTOxTM System 

NOx emissions from the anode bake furnace could potentially be reduced by using the LoTOxTM

system for post-combustion control. This technology has a control efficiency of 90% for NOx

emissions when combined with wet scrubbing, resulting in a potential reduction in NOx

emissions of approximately 122 tons/year. 

5.3 EVALUATION OF COSTS AND OTHER IMPACTS

Step 4 of the BART analysis involves evaluation of cost and other impacts, including energy 

impacts, greenhouse gas generation, non-air quality environmental impacts, and remaining useful 

life. Costs of control, energy impacts, greenhouse gas generation impacts, non-air quality 

environmental impacts, and remaining useful life are evaluated in this section. 

5.3.1 Cost Impacts for Feasible Controls 

5.3.1.1 Wet Scrubbers 

The exhaust gases from each potline are routed to dry alumina reactors. Potline gases 

currently exhaust to atmosphere from stacks above the fabric filters in each of the six 

baghouse scrubbing centers, which are located in courtyards between the potrooms. 

Wet scrubber costs for Intalco were estimated based on cost quotes received by Alcoa 

from two flue gas desulphurization equipment vendors. The cost quotes were originally 

provided as part of the BART analysis for Alcoa’s Tennessee Operations in Alcoa, TN. 
Intalco BART Determination FINAL.doc 5-19 

Both vendors provided cost proposals for wet scrubbing systems based on limestone 

forced oxidation (LSFO) SO2 scrubbers. Lime- or sodium-based scrubbers could also be 

used for potlines, but lime and sodium are less desirable reagents considering that these 

reagents are much more expensive. An advantage of the limestone forced oxidation 

process is that the spent slurry is oxidized to gypsum, which dewaters more efficiently, 

resulting in less waste materials requiring disposal. Thus, an LFSO scrubber was 

determined to be the most appropriate control device for the cost analysis. The vendor 

proposals are provided in Appendix B. These proposals contain confidential business 

information and are, therefore, labeled as confidential. 

Neither of the two vendors provided a comprehensive installed cost estimate. Both 

preliminary designs were based on a central scrubbing center as the least cost approach, 

where exhaust from all dry scrubbing systems would be ducted to a centralized scrubbing 

system. Both design estimates were based on systems that would provide 100% 

availability of emissions control on each day of the year, given that potlines cannot be 

easily shutdown and restarted for control system outages. 

One vendor provided an estimate of the scrubber equipment only. The other provided an 

“indicative price,” with an installed cost assumed equal to the equipment cost. Important 

retrofit considerations for installing a potline wet scrubbing system include: (1) that gases 

must be collected from multiple individual baghouse stacks, (2) the system must 

simultaneously maintain balanced flow from multiple potline control devices, and (3) the 

system installation would require transport of new components through narrow passages 

in the existing potline. Coordination of the equipment delivery and the daily work 

schedule of the potline operation would also affect the control system installation. One 

of the vendors recognized the complexity of this project, pointing out in their proposal 

that an extensive engineering effort was needed because of space limitations, access 

limitations, uncertainty as to laydown areas, and uncertainty of ductwork and supports. 

These retrofit issues would apply equally to both the Alcoa, TN facility and Intalco. 

The vendor cost proposals for the Tennessee facility were based on a total scrubber exit 

gas volume of approximately 1,580,000 acfm at 101o

F compared to a design exit gas 

volume of approximately 1,950,000 acfm at 98o

F for Intalco. Vendor equipment cost 

proposals for the Alcoa, TN facility therefore had to be adjusted to account for 

differences in exhaust gas volume and other design parameters. 

Hatch, an engineering firm contracted by Alcoa, prepared a pre-feasibility report for 

Intalco in which equipment costs provided by one of the vendors for the Alcoa, TN 

facility were scaled or adjusted to estimate LSFO equipment costs for Intalco. The 

procedure used by Hatch adjusted equipment cost estimates using appropriate exponential 
Intalco BART Determination FINAL.doc 5-20 

factors for equipment type (reagent feed, SO2 removal, gas handling, etc.), along with 

differences in system exhaust gas volume, limestone consumption, and gypsum byproduct generation. ENVIRON used the cost adjustment approach developed by Hatch 

to prepare an average equipment cost based on both vendor quotations. The equipment 

cost scaling procedures are outlined in the Hatch report in Appendix C and ENVIRON’s 

parallel calculations based on the average of the two vendor quotes are provided in 

Appendix D. 

The average scrubber equipment cost was used with factors from the EPA Air Pollution 

Cost Control Manual25 to determine installation costs and total capital costs. Operating 

costs were calculated based on utility and raw material requirements provided by Hatch, 

along with unit cost information provided by Intalco and other cost assumptions from the 

EPA Air Pollution Cost Control Manual. Complete cost calculations and assumptions 

are provided in Appendix D. 

Separate vendor cost quotes were not obtained for installing a wet SO2 scrubbing system 

on the anode bake furnace. Instead, the potline SO2 scrubber equipment costs were 

scaled to estimate Intalco anode bake control equipment costs using the same approach 

discussed above for the potlines. The anode bake wet scrubber design was based on a 

scrubber exhaust gas volume of 202,500 acfm at 98oF. The vendor equipment costs were 

adjusted using exponential factors that account for differences in exhaust gas volume, 

limestone consumption, and gypsum by-product generation. 

Table 5-3 summarizes the cost of installing and operating an LSFO wet scrubber on the 

Intalco potlines and anode bake furnace to remove 95% of the SO2. The capital and total 

annualized costs for a potline wet scrubber are high at approximately $234.5 million and 

$46.8 million per year, respectively. The wet scrubber cost effectiveness is also high at 

$7,500 per ton of SO2 removed. 

The estimated installed capital cost to add a wet scrubber to remove 95% of the SO2 from 

the anode bake furnace exhaust would be approximately $29.5 million with an annualized 

cost of $6.3 million per year. The wet scrubber cost effectiveness is also high at $36,400 

per ton of SO2 removed. 

5.3.1.2 Coke Sulfur Limit 

Intalco is currently able to obtain coke with 3.0% sulfur without incurring significant additional 

cost. However, as low sulfur coke becomes more difficult to procure, the cost will increase. 

Additional information regarding low sulfur coke availability is included in Appendix B. 

 

25 USEPA. 2000. EPA Air Pollution Cost Control Manual, Sixth Edition. EPA-452/B-02-001. January 2002 (and 

updates). 
Intalco BART Determination FINAL.doc 5-21 

5.3.1.3 Anode Bake Furnace LoTOxTM System 

Cost data for the LoTOxTM system is not readily available. However, as demonstrated above for 

the control of SO2 emissions from the anode bake furnace, the cost of the downstream scrubber 

required for the use of the LoTOxTM system would make this option cost prohibitive. NOx

emissions are lower than SO2 emissions for the anode bake furnace, so the cost per ton values for 

NOx would be even higher than for SO2. 

5.3.2 Energy Impacts 

A wet scrubber removes SO2 by forcing the exhaust gas through a spray tower or absorber where 

it contacts water droplets that contain the unreacted lime or limestone. Energy is required to 

overcome the resistance of the scrubber components as well as falling water droplets. A 

substantial amount of energy would be associated with fans to move the potline and anode bake 

furnace exhaust streams through scrubbers. Other energy is required for the slurry pumps, 

instrumentation, and miscellaneous items (e.g., lighting). The total energy required26 would be 

approximately 7,400 kilowatt-hours (kWh)/hr for the potline scrubber and 750 kWh/hr for the 

anode bake furnace scrubber. As listed in Table 5-3, this is equivalent to 64,824,000 kWh of 

electricity per year for the potline scrubber. A wet scrubber on the anode bake furnace would 

add 6,570,000 kWh per year. 

5.3.3 Greenhouse Gas Generation 

Greenhouse gases (GHGs) are gaseous compounds that are known to provide a warming effect to 

the atmosphere. The predominant GHG is carbon dioxide (CO2). Other GHGs include nitrous 

oxide and methane. The proposed SO2 control devices will increase overall emissions of GHGs 

via three mechanisms: (1) as a byproduct of the reaction chemistry in the scrubbers, (2) as 

indirect emissions from the generation of electricity required to power the scrubbing systems, 

and (3) as direct emissions from vehicle travel for the additional personnel that will be required 

at the facility to maintain and operate the scrubbing systems. The details of the GHG emission 

calculations for each of these mechanisms are presented in the Appendix E. 

The total GHGs (in carbon dioxide equivalents) generated by the implementation of the proposed 

scrubbing system for the potline fumes was estimated to be 96,441 pounds per day, or 17,597 

tons per year. The total GHGs (in carbon dioxide equivalents) generated by the implementation 

of the proposed scrubbing system for the anode baking furnace was estimated to be 7,298 pounds 

per day, or 1,330 tons per year. 

5.3.4 Non-Air Quality Environmental Impacts 

Both of the wet scrubber proposals were based on the LSFO process. This process oxidizes the 

spent slurry to gypsum, which may be landfilled or commercially sold. There is no way to know 
Intalco BART Determination FINAL.doc 5-22 

at this time whether the gypsum would have commercial value or whether there would be any 

demand for it. Therefore, it must be assumed that 27,130 tons of waste from a potline wet 

scrubber and 639.5 tons of waste from an anode bake furnace wet scrubber would be landfilled 

each year. 

It is estimated that 182.5 million gallons of water will be required annually to operate the potline 

wet scrubber at a cost of approximately $97,000. This will significantly impact the community 

infrastructure in that this will increase Intalco’s daily water demand by approximately 9%27. 

It is also estimated that a total of approximately 71.4 million kWh would be needed to operate 

the potline and anode bake furnace scrubbers annually. This would impact power demand in the 

community and would also have an environmental impact due to power production equivalent to 

adding approximately 6,700 new households in the community28. 

5.3.5 Remaining Useful Life 

The Intalco smelter has been in operation since 1966 and remains a critical component of 

Alcoa’s aluminum production in the United States. The facility intends to be in operation 

throughout the period of the Regional Haze Program. 

5.4 EVALUATE VISIBILITY IMPACTS

Step 5 of the BART analysis involves evaluation of visibility impacts. More specifically, this is 

an evaluation of the potential improvement in visibility resulting from application of feasible 

pollution prevention/add-on control options. Refined CALPUFF modeling was performed for 

two control scenarios: one with wet SO2 scrubbing applied to the potline and one with wet SO2

scrubbing applied to the anode bake furnace. This modeling was accomplished according to 

State of Washington’s BART modeling protocol29. In general, this modeling was the same as the 

baseline modeling except stack data and emission data associated with the application of the 

feasible add-on controls were used as model inputs. Table 5-4 presents the post-control 

modeling source input data that were used in the CALPUFF model to forecast visibility impacts 

for the two control options. 

Table 5-5 presents the results of modeling with the two scrubber SO2 control scenarios along 

with baseline impacts. As shown in Table 5-5, the addition of a potline wet scrubber reduced 

 26 Hatch. 2007. SO2 Scrubbing for the INTALCO Primary Aluminum Smelter: Pre-Feasibility Report. July 26. 27 Based on average facility incoming water flow rates for 1998 through 2000, the three most recent years the 

facility was at full production. 28 Calculated based on 2001 average energy usage per household for the United States as reported by the 

Department of Energy (http://www.eia.doe.gov/emeu/reps/enduse/er01_us_tab1.html). 

29 Modeling Protocol for Washington, Oregon, and Idaho: Protocol for the Application of the CALPUFF Modeling 

System Pursuant to the Best Available Retrofit Technology (BART) Regulation. October 11, 2006. 

www.deq.state.or.us/aq/haze/docs/bartprotocol.pdf 
Intalco BART Determination FINAL.doc 5-23 

modeled visibility impacts in all five Class I areas to between approximately 0.1 and 0.35 dv for 

the three years modeled. For example, the baseline modeling results indicate that the highest 98th

percentile visibility impact from Intalco’s BART-eligible sources at Olympic National Park with 

3% sulfur in the coke was 1.527 dv. The post-control modeling results indicate that the highest 

98th percentile visibility impact from Intalco’s BART-eligible sources at Olympic National Park 

with wet scrubbers installed on the potlines was 0.355 dv in 2003. This represents a 1.17 dv 

reduction in total facility visibility impacts at Olympic National Park with the addition of wet 

scrubbers on the potlines. 

The modeled visibility improvements shown in Table 5-5 from adding a wet scrubber at the 

anode bake furnace are minimal, with improvements ranging from approximately 0.004 to 0.024 

dv compared to the baseline conditions. For example, the post-control modeling results for the 

anode bake furnace indicate a highest 98th percentile visibility impact of 1.503 dv compared to 

the baseline value of 1.527 dv in 2003. This represents less than a 2% reduction in total facility 

visibility impacts at Olympic National Park with the addition of wet scrubbers on the anode bake 

furnace. 

For NOx, the use of an advanced firing system or LoTOxTM technology for the anode bake 

furnace would also result in minimal improvements in visibility. The baseline visibility 

modeling indicated that the highest 98th percentile visibility impact due to anode bake furnace 

NOx emissions was approximately 0.03 dv (55% of 0.053 dv). Therefore, a 20% reduction in 

NOx emissions from the anode bake furnace with the use of an advanced firing system would 

reduce Intalco’s total visibility impacts by approximately 0.006 dv and a 90% reduction with the 

use of LoTOxTM would reduce the impacts by approximately 0.027 dv. Based on the minimal 

change in visibility forecast resulting from the installation of an advanced firing system or use of 

LoTOxTM, it was determined that neither of these technologies represents reasonably effective 

BART control technologies for the anode bake furnace. 
 

Intalco BART Determination FINAL.doc 6-1

6.0 DETERMINATION OF BART 

6.1 ALUMINUM POTLINES

For potline SO2 emissions, BART was determined to be the current level of control, which is a 

pollution prevention limit of 3% sulfur in the coke used to manufacture anodes. A pollution 

prevention limit based on coke sulfur contents below 3% was determined by Intalco to be 

infeasible as BART for 2013 and beyond based on a market and availability analysis for future 

coke supply. Use of wet scrubbing technology to reduce potline SO2 emissions was rejected as 

BART due to excessive costs: total cost effectiveness of $7,500 per ton of SO2 removed and 

capital and total annualized costs of $234.5 million and $46.8 million per year, respectively. A 

potline wet scrubber would also have substantial secondary impacts, including increased energy 

usage of 64,824,000 kWh of electricity per year, added water consumption of 183 million 

gallons per year, and solid waste generation of 27,000 tons per year. 

For PM emissions, BART was determined to be the current level of control, which is the use of 

baghouses to control PM emissions from the alumina dry scrubbers and wet roof scrubbers to 

control secondary PM emissions from the potroom roofs. 

There are no feasible technologies for control of NOx from the potlines; thus, BART for NOx

was determined to be no controls. 

6.2 ANODE BAKE FURNACE

A pollution prevention limit of 3% sulfur in the coke was also determined to be BART for anode 

bake furnace SO2 emissions. The cost of wet scrubbing to reduce SO2 emissions would be 

excessive at $36,400 per ton of SO2 removed while providing minimal visibility improvement. 

The existing level of control (based on baghouses on the alumina dry scrubbers) was determined 

to be BART for PM emissions. 

BART for anode bake furnace NOx emissions was determined to be no controls. The use of an 

advanced firing system for reduced energy use was rejected as BART because the technology 

would result in negligible visibility improvement. Similarly, the use of LoTOxTM was rejected as 

BART because the cost of the technology would be excessive and result in negligible visibility 

improvement. 
 

Intalco BART Determination FINAL.doc 6-2

6.3 ALUMINUM HOLDING FURNACES

BART for the aluminum holding furnaces was determined to be no controls. The use of 

additional controls was rejected as BART because any visibility improvement would be 

negligible. 

6.4 MATERIAL HANDLING AND TRANSFER OPERATIONS

PM emissions from the BART-eligible material handling and transfer operations are all 

controlled using fabric filter technology. This existing level of emissions control was determined 

to be BART for these material handling and transfer operations. 
TABLES 
Process 

Number

Emission Unit 

ID Emission Unit Description

Visibility 

Impairing 

Pollutants

Existing 

Pollution 

Controls

Modeling Source 

Type

5 181-186 Potline primary emission control system stacks PM, SOx

Reactor/ 

Fabric Filter Point

5 22-180 Potline secondary emission control system stacks PM, SOx

Roof Water 

Scrubbers Line

3 187 Anode bake furnace PM, SOx, NOx

Reactor/ 

Fabric Filter Point

6 4, 5, 7, 8, 10, 11, 

13, 14, 16-19 Aluminum holding furnaces PM Fabric Filter Point

2 188 Paste plant baghouse stack PM Fabric Filter Point

2 189 Phase A ball mill baghouse stack PM Fabric Filter Point

2 191 Phase B ball mill baghouse stack PM Fabric Filter Point

7 195 Primary WTP kiln wet scrubber PM Wet Scrubber Point

4 198 Rod shop (west) baghouse stack PM Fabric Filter Point

4 199 Rod shop (east) baghouse stack PM Fabric Filter Point

7 208 Ladle cleaning baghouse stack PM Fabric Filter Point

7 209 Autogenous mill baghouse stack PM Fabric Filter Point

7 210 TAC station baghouse stack PM Fabric Filter Point

6 217 Remelt furnace stack PM Point

2 232 Butts baghouse stack PM Fabric Filter Point

4 260 Aluminum spray cyclone stack PM Point

4 312 Rod shop induction furnace (east) stack PM Point

4 313 Rod shop induction furnace (west) stack PM Point

2 316 Pitch fume treatment system PM Point

3 251 Anode bake building monitor roof PM Volume

3 252 Anode block hole blower PM Volume

4 257A Rod shop crust recovery discharge to trucks from bins #1 and #2 PM Volume

4 257B Rod shop crust recovery discharge to trucks from bins #1 and #2 PM Volume

4 259A Rod shop carbon recovery discharge to trucks from bins #1 and #2 PM Volume

4 259B Rod shop carbon recovery discharge to trucks from bins #1 and #2 PM Volume

7 280 Annex cathode assembly area roof vents PM Volume

7 282 Annex ramming paste area roof vents PM Volume

1 239 Paved road vehicle dust emissions PM Area

1 241 Facility-wide natural gas combustion PM, SOx, NOx Area

7 273 Alumina ore handling fugitive dust PM Area

1 233 General welding PM Volume (combined)

1 240 Fugitive dust from loading and dumping waste PM Volume (combined)

1 242 Plant-wide propane combustion emissions PM, SOx, NOx Volume (combined)

2 190 Phase "A" mixer fugitives PM Volume (combined)

2 192 Phase "B" mixer fugitives PM Volume (combined)

2 193 KVS ball mill baghouse stack PM Fabric Filter Volume (combined)

2 194 Pet coke baghouse stack PM Fabric Filter Volume (combined)

2 243 Paste plant roof vents PM, SOx, NOx Volume (combined)

2 244 Phase "A" paste cooling conveyor fugitives PM Volume (combined)

2 245 Phase "B" paste cooling conveyor fugitives PM Volume (combined)

2 248 Scrap paste storage bins PM Volume (combined)

2 249 Paste plant vacuum system baghouse stack PM Fabric Filter Volume (combined)

3 250 Packing coke silo vent PM Volume (combined)

4 253 Rod shop roof vents (north) PM Volume (combined)

4 254 Rod shop roof vents (south) PM Volume (combined)

4 255 Hot anode butts transport PM Volume (combined)

4 256A,B Rod shop crust recovery discharge to storage bins #1 and #2 PM Volume (combined)

4 258A,B Rod shop carbon recovery discharge to storage bins #1 and #2 PM Volume (combined)

4 263 Cooling of cast iron dross sows outside rod shop PM Volume (combined)

Table 3-1

Primary Aluminum Reduction Emission Units

Alcoa Intalco Works

Ferndale, Washington
Process 

Number

Emission Unit 

ID Emission Unit Description

Visibility 

Impairing 

Pollutants

Existing 

Pollution 

Controls

Modeling Source 

Type

Table 3-1

Primary Aluminum Reduction Emission Units

Alcoa Intalco Works

Ferndale, Washington

5 238 Auxiliary diesel generators PM, SOx, NOx Volume (combined)

6 3, 6, 9, 12, 15 Casting pit steam exhaust stacks PM Volume (combined)

6 21 Pigger cooling conveyor exhaust stack PM Volume (combined)

6 220a, 220b, 

221a, 221b MHD holding furnaces PM Volume (combined)

6 266 Casthouse monitor roof PM Volume (combined)

6 269 Pigger aluminum furnace door exhaust hood PM Volume (combined)

6 315 Dross/silicon storage baghouse PM Fabric Filter Volume (combined)

7 196 Primary WTP reclaimed storage silo baghouse stack PM Fabric Filter Volume (combined)

7 206 Pangborn baghouse stack PM Fabric Filter Volume (combined)

7 207 Annex paste plant baghouse stack PM Fabric Filter Volume (combined)

7 211 Alumina ore silo #1 baghouse stack PM Fabric Filter Volume (combined)

7 212 Alumina ore silo #2 baghouse stack PM Fabric Filter Volume (combined)

7 213 Alumina ore silo #3 baghouse stack PM Fabric Filter Volume (combined)

7 214 Alumina ore silo #4 railcar unloader baghouse stack PM Fabric Filter Volume (combined)

7 215 Alumina ore pier-head transfer point baghouse stack PM Fabric Filter Volume (combined)

7 216 Alumina ore ship unloading baghouse stack PM Fabric Filter Volume (combined)

7 226 Aluminum fluoride silo baghouse stack PM Fabric Filter Volume (combined)

7 228 Covered annex bunkers for crust and digout PM Volume (combined)

7 229 Brick crushing facility baghouse stack PM Fabric Filter Volume (combined)

7 274 Alumina silo #4 truck loader baghouse stack PM Fabric Filter Volume (combined)

7 275 Aluminum fluoride/anthracite railcar unloading fugitive dust PM Volume (combined)

7 276 Coke unloading and transfer fugitive dust PM Volume (combined)

7 281 Annex ramming paste area roof vents PM Volume (combined)

7 284 Annex west pitch melter stack PM Volume (combined)

7 285 Annex east pitch melter stack PM Volume (combined)

7 286 Annex ramming paste mixer stack PM Volume (combined)

7 287 Autogenous mill silo baghouse stack PM Fabric Filter Volume (combined)

7 293 Baghouse hopper unloading PM Volume (combined)

7 295 Landfill - solid waste PM Volume (combined)

7 296 Landfill - RCRA waste PM Volume (combined)

7 306 Alumina ore ship unloader clamshell PM Volume (combined)

8 222 Paint shop shot blaster baghouse stack PM Fabric Filter Volume (combined)
LCC 

Coordinate 

X

LCC 

Coordinate 

Y

Stack 

Height

Base 

Elevation

Effective 

Stack 

Diameter

Exit 

Velocity

Flow 

Rate

Exit 

Temperature

PM10 

Emission 

Rate

Filterable 

PM2.5 

Emission 

Rate

Conde

PM

Emi

R

(km) (km) (m) (m) (m) (m/s) (m3/s) (°K) (g/s) (g/s) (g

DSA1 -120.536 -14.914 19.8 65.4 3.733 12.98 142.1 363.7 1.81 0.097 1.DSA2 -120.466 -15.150 19.8 63.9 3.733 13.05 142.8 363.7 1.81 0.097 1.

DSB3 -120.691 -14.958 17.9 62.2 5.957 5.17 144.1 353.1 1.81 0.097 1.DSB4 -120.621 -15.195 17.9 61.4 5.957 5.17 144.1 353.1 1.81 0.097 1.DSC5 -120.840 -15.000 17.9 59.7 5.723 4.90 126.0 355.1 1.81 0.097 1.DSC6 -120.770 -15.238 17.9 59.0 5.723 4.79 123.2 355.1 1.81 0.097 1.

BAKEOVEN -121.011 -15.391 25.5 57.5 2.129 12.98 46.2 369.4 0.35 0.15 0.

CAST1-6 -120.392 -15.061 26.9 66.1 2.365 5.69 25.0 433.0 0.33 0.079 0.CAST7-8 -120.415 -14.965 23.2 66.1 1.365 5.69 8.3 433.0 0.11 0.026 0.0

CAST9-10 -120.422 -14.960 18.4 66.1 1.365 5.69 8.3 433.0 0.11 0.026 0.0

CAST11-12 -120.433 -14.922 23.2 66.1 1.365 5.69 8.3 433.0 0.11 0.026 0.0

188 -120.933 -15.393 36.1 58.5 1.462 5.34 9.0 Ambient 0.010 0.010189 -120.919 -15.088 36.1 58.5 1.287 3.63 4.7 Ambient 0.090 0.090191 -120.940 -15.395 36.1 58.5 1.287 3.63 4.7 Ambient 0.090 0.090195 -120.553 -15.394 17.7 63.1 0.61 4.29 1.3 343.0 0.080 0.080198 -120.957 -15.122 13.3 58.5 1.219 20.23 23.6 Ambient 0.24 0.24199 -120.953 -15.121 13.3 58.5 1.219 20.23 23.6 Ambient 0.24 0.24208 -121.006 -15.002 5.0 58.5 1.828 2.53 6.6 Ambient 0.076 0.076209 -121.095 -14.985 15.7 74.4 0.914 36.19 23.7 Ambient 0.43 0.43210 -120.400 -15.282 9.4 65.2 0.762 3.11 1.4 395.0 0.00018 0.00018217 -120.360 -15.210 23.2 77 1.365 5.69 8.3 433.0 0.026 0.0035 0.0232 -120.931 -15.423 6.6 58.2 0.61 29.12 8.5 Ambient 0.097 0.097260 -120.925 -15.134 11 59.1 0.26 1.46 0.08 Ambient 0.025 0.025312 -120.922 -15.099 13.7 58.5 0.49 1.59 0.30 370.0 0.11 0.11313 -120.941 -15.104 13.7 58.5 0.49 1.59 0.30 370.0 0.11 0.11316 -120.858 -15.400 22.86 57.96 1.372 15.9 23.5 302.9 0.30 0.30

Source 

Description

Table 4-1

Source Input Data for Baseline Modeling - Point Sources

Alcoa Intalco Works

Ferndale, Washington
Roof Scrubber Water On Conditions

LCC 

Coordinate 

Begin X

LCC 

Coordinate 

Begin Y

LCC 

Coordinate 

End X

LCC 

Coordinate 

End Y

Release 

Height

Base 

Elevation

Line 

Source 

Width

Exit 

Velocity

Flow 

Rate

Buoyancy 

Parameter

PM10 

Emission 

Rate

Filterable 

PM2.5 

Emission 

Rate

C

(km) (km) (km) (km) (m) (m) (m) (m/s) (m3/s) (m4/s3) (g/s) (g/s) 

WSLINEA1 -120.532 -14.845 -120.422 -15.219 16.40 65.4 4.24 3.920 55.32 410.22 2.30 0.87 WSLINEA2 -120.606 -14.867 -120.496 -15.241 16.40 64.1 4.24 3.920 55.32 410.22 2.30 0.87 

WSLINEB1 -120.681 -14.892 -120.571 -15.266 16.40 62.9 4.24 3.990 56.30 417.52 2.30 0.87 WSLINEB2 -120.755 -14.914 -120.645 -15.288 16.40 61.7 4.24 3.990 56.30 417.52 2.30 0.87 WSLINEC1 -120.828 -14.936 -120.719 -15.309 16.40 60.5 4.24 3.904 55.08 408.49 2.30 0.87 WSLINEC2 -120.903 -14.958 -120.793 -15.332 16.40 59.3 4.24 3.904 55.08 408.49 2.30 0.87 

Roof Scrubber Water Off Conditions

LCC 

Coordinate 

Begin X

LCC 

Coordinate 

Begin Y

LCC 

Coordinate 

End X

LCC 

Coordinate 

End Y

Release 

Height

Base 

Elevation

Line 

Source 

Width

Exit 

Velocity

Flow 

Rate

Buoyancy 

Parameter

PM10 

Emission 

Rate

Filterable 

PM2.5 

Emission 

Rate

C

(km) (km) (km) (km) (m) (m) (m) (m/s) (m3/s) (m4/s3) (g/s) (g/s) 

WSLINEA1 -120.532 -14.845 -120.422 -15.219 16.40 65.4 4.24 3.920 55.32 860.33 11.94 4.48 WSLINEA2 -120.606 -14.867 -120.496 -15.241 16.40 64.1 4.24 3.920 55.32 860.33 11.94 4.48 

WSLINEB1 -120.681 -14.892 -120.571 -15.266 16.40 62.9 4.24 3.990 56.30 875.62 11.94 4.48 WSLINEB2 -120.755 -14.914 -120.645 -15.288 16.40 61.7 4.24 3.990 56.30 875.62 11.94 4.48 WSLINEC1 -120.828 -14.936 -120.719 -15.309 16.40 60.5 4.24 3.904 55.08 856.70 11.94 4.48 WSLINEC2 -120.903 -14.958 -120.793 -15.332 16.40 59.3 4.24 3.904 55.08 856.70 11.94 4.48 

Source 

Description

Source 

Description

Table 4-2

Source Input Data for Baseline Modeling - Line Sources

Alcoa Intalco Works

Ferndale, Washington
Southwest 

Corner LCC 

Coordinate X

Southwest 

Corner LCC 

Coordinate Y

Release 

Height

Initial 

σz

Base 

Elevation

Total 

Area

PM10 

Emission 

Rate

Filterable 

PM2.5 

Emission 

Rate

Cond

P

Em

R

(km) (km) (m) (m) (m) (m2) (g/s/m2) (g/s/m2) (g/

239 Fugitive dust from vehicle travel on paved roads -120.536 -14.914 5 10 60 720,000 0.00000040 0.000000059 241 Facility-wide natural gas combustion (fugitive) -120.466 -15.150 15 15 60 720,000 0.00000022 0.00000022 273 Alumina ore handling fugitive dust -120.691 -14.958 15 15 60 720,000 0.000000053 0.0000000080 

Source 

ID Source Description

Table 4-3

Source Input Data for Baseline Modeling - Area Sources

Alcoa Intalco Works

Ferndale, Washington
Reference 

LCC 

Coordinate 

X

Reference 

LCC 

Coordinate 

Y

Release 

Height

Initial 

σy

Initial 

σz

Base 

Elevation

PM10 

Emission 

Rate

Filterable 

PM2.5 

Emission 

Rate

(km) (km) (m) (m) (m) (m) (g/s) (g/s) 

251 Anode bake building monitor roof -120.982 -15.242 22 33.7 10.2 58.7 0.13 0.13 252 Anode block hole blower -120.982 -14.242 22 33.7 10.2 58.7 0.12 0.12 

257A Rod shop crust recovery discharge to trucks from bins #1 and #2 -120.948 -15.123 4.6 1.07 1.07 58.5 0.0021 0.00032 

257B Rod shop crust recovery discharge to trucks from bins #1 and #2 -120.906 -15.112 4.6 1.07 1.07 58.5 0.0021 0.00032 

259A Rod shop carbon recovery discharge to trucks from bins #1 and #2 -120.948 -15.123 4.6 1.07 1.07 58.5 0.0030 0.00046 

259B Rod shop carbon recovery discharge to trucks from bins #1 and #2 -120.906 -15.112 4.6 1.07 1.07 58.5 0.0030 0.00046 

280 Annex cathode assembly area roof vent -120.983 -15.013 18.3 8.97 8.51 58.5 0.054 0.054 282 Annex ladle rebuild area rood vents -120.952 -14.99 18.3 8.97 8.51 58.5 0.38 0.38 

Others1 Other sources smaller than 0.1 g/s, combined (no SOx or NOx) -120.665 -15.076 4.6 1.07 1.07 62.0 0.358 0.307 

Others2 Other sources greater than 0.1 g/s, combined (no SOx or NOx) -120.665 -15.076 4.6 1.07 1.07 62.0 0.849 0.7414 

Others3 Other sources, combined (with SOx or NOx emissions) -120.665 -15.076 4.6 1.07 1.07 62.0 0.1722 0.1676 

Source 

ID Source Description

Table 4-4

Source Input Data for Baseline Modeling - Volume Sources

Alcoa Intalco Works

Ferndale, Washington
Modeled 

98th 

Percentile

Modeled 

98th 

Percentile

Modeled 

98th 

Percentile

(deciview) (deciview) (deciview)

Alpine Lakes Wilderness Area 1.244 36 0.965 37 0.881 23

Goat Rock Wilderness Area 0.500 8 0.579 10 0.317 3

Glacier Peak Wilderness Area 1.161 37 1.156 38 0.736 23

Mount Adams Wilderness Area 0.456 7 0.472 6 0.357 2

Mount Rainier National Park 0.843 22 1.052 26 0.629 15

North Cascades National Park 1.376 65 1.395 56 1.138 32

Olympic National Park 2.363 59 1.858 53 2.136 45

Pasayten Wilderness Area 0.866 30 0.871 33 0.659 13

Note:

2003

Number of 

Days 

Exceeding 

0.5 dv

2004

Number of 

Days 

Exceeding 

0.5 dv

Modeled visibility impacts that exceed the 0.5 dv contribution threshold are presented in bold in this table.

Table 4-5

Screening Baseline Visibility Modeling Results

Alcoa Intalco Works

Ferndale, Washington

Class I Area

2005

Number of 

Days 

Exceeding 

0.5 dv
Modeled 

98th 

Percentile

Modeled 

98th 

Percentile

Modeled 

98th 

Percentile

(deciview) (deciview) (deciview)

Alpine Lakes Wilderness Area 0.738 24 0.742 18 0.632 9

Goat Rock Wilderness Area 0.332 4 0.287 5 0.194 0

Glacier Peak Wilderness Area 0.916 24 0.769 25 0.552 10

Mount Rainier National Park 0.660 11 0.574 9 0.414 3

North Cascades National Park 0.936 36 0.986 35 0.693 14

Olympic National Park 1.527 41 1.369 37 1.225 34

Pasayten Wilderness Area 0.448 6 0.469 6 0.412 2

Note:

Table 4-6

Refined Baseline Visibility Modeling Results

Alcoa Intalco Works

Ferndale, Washington

Modeled visibility impacts that exceed the 0.5 dv contribution threshold are presented in bold in this table.

Class I Area

2005

Number of 

Days 

Exceeding 

0.5 dv

2003

Number of 

Days 

Exceeding 

0.5 dv

2004

Number of 

Days 

Exceeding 

0.5 dv
Modeled 98th 

Percentile

(deciview) SO4 NO3 Filterable PM2.5 Coarse PM Co

Total of all sources 1.527 92.5% 3.0% 0.5% 0.5% Potline primary emission controls 1.414 96.6% 0% 0.05% 0.3% 

Potline secondary emission controls 0.026 67.6% 0% 5% 5.4% Anode bake furnace 0.048 59.4% 39.1% 0% 0% 

Casthouse stacks 0.002 0% 0% 0% 0% All other stacks 0.003 0% 0% 80.0% 20.0% All volume sources 0.022 6.3% 75.0% 12.5% 6.3% All area sources 0.011 0% 93.8% 0% 0% Total of all sources 1.369 80.8% 4.4% 1.7% 2.4% Potline primary emission controls 1.142 90.6% 0% 0.12% 1.1% 

Potline secondary emission controls 0.124 40.4% 0% 10.1% 11.8% Anode bake furnace 0.053 40.8% 55.3% 1.3% 1.3% Casthouse stacks 0.004 0% 0% 16.7% 16.7% All other stacks 0.006 0% 0% 66.7% 33.3% All volume sources 0.025 2.8% 69.4% 16.7% 11.1% All area sources 0.014 0% 95.0% 5.0% 5.0% Total of all sources 1.225 90.3% 2.5% 0.95% 0.89% Potline primary emission controls 1.080 95.7% 0% 0% 0% 

Potline secondary emission controls 0.079 61.5% 0% 7.3% 5.5% Anode bake furnace 0.039 62.3% 34.0% 0% 0% Casthouse stacks 0.001 0% 0% 0% 0% All other stacks 0.003 0% 0% 75.0% 25.0% All volume sources 0.016 4.5% 68.2% 13.6% 9.1% All area sources 0.007 0% 90.0% 0% 0% 

200320042005

Year Source Group

Percentage of Species Contribution

Table 4-7

Culpability Analysis for Refined Baseline Visibility Modeling Results in Olympic National Park

Alcoa Intalco Works

Ferndale, Washington
RBLC ID Facility Last Update Process Pollutant Control Option Percent Efficiency E

KY-0070 NSA - A Division of Southwire Company 03/02/2004 Potline 5 SO2 Wet scrubber1 93% 

SC-0037 Alumax of South Carolina 09/17/2002 Potroom Groups (4) PM Existing dry alumina scrubbers (fabric filter) SC-0037 Alumax of South Carolina 09/17/2002 Potroom Groups (4) SO2 Limit maximum % sulfur of anode coke to 2.95%; limit maximum % sulfur of anode pitch to 1.2% 

SC-0037 Alumax of South Carolina 09/17/2002 Anode Bake Plant SO2

No upgrade; limit maximum % sulfur of anode coke to 2.95%; limit maximum % sulfur of anode pitch to 1.2%

SC-0037 Alumax of South Carolina 09/17/2002 Anode Bake Plant PM No upgrade; limit sulfur content of raw materials SC-0037 Alumax of South Carolina 09/17/2002 Anode Bake Plant NOx No upgrade; limit sulfur content of raw materials 

KY-0041 Arco Metals Co. 12/18/2001 Primary Aluminum Reduction Potline PM Baghouse, hooding for raw material handling 98% 

KY-0041 Arco Metals Co. 12/18/2001 Primary Aluminum Reduction Potline SO2 Fuel spec: low sulfur coke and pitch (calc. 3% sulfur) 

OR-0002 Alumax Pacific Corp. 12/18/2001 Entire Plant PM Baghouse 5.4 lb

5.0 lb

OR-0002 Alumax Pacific Corp. 12/18/2001 Anode Coke SO2 Fuel spec: sulfur limit in coke 

WA-0003 Alcoa 12/18/2001 Potlines 1, 2, and 3 SO2 Fuel spec: limit S content in coke, raw 

NC-0003 Alcoa 01/28/2002 Potline 3 PM Fabric filter NC-0003 Alcoa 01/28/2002 Potline 3 SO2 

NC-0003 Alcoa 01/28/2002 Anode Production SO2 

NC-0003 Alcoa 01/28/2002 Anode Production PM 

MO-0036 Noranda Aluminum, Inc. 05/09/2006 Carbon Baking Furnace for Potline 3 PM10 

MO-0036 Noranda Aluminum, Inc. 05/09/2006 Potline 1 PM10 Coated filter dry scrubber 

MO-0036 Noranda Aluminum, Inc. 05/09/2006 Potline 3 PM10 Coated filter dry scrubber 

Note:

1 This wet scrubber is not actually used or required by permit.

Table 5-1

RBLC Database Search Results for Primary Aluminum Facilities

Alcoa Intalco Works

Ferndale, Washington
Emissions Emissions Emissions Emission

(tons/yr) (tons/yr) (tons/yr) (tons/yr

1 LSFO Scrubber for Potlines 854 88 136 0 984 (42) 1,113 2 LSFO Scrubber for Anode Bake Furnace 6,904 2 136 0 747 (8) 921 

Current 

Allowable 

Emissions

Operating Limit of 3% Sulfur in Coke 7,076 136 693 869

Notes:

SO2 NOx

Table 5-2

Post Control Emission Rates1

Alcoa Intalco Works

Ferndale, Washington

% Reduction 

(Increase)2

1 Emission rates include the potline primary control system, the potline secondary control system emissions, and the anode ba

emissions.

2 Compared with current potential emissions.

PM2.5 

% Reduction 

(Increase)2

% Reduction 

(Increase)2

Control 

Scenario

SO2 Control 

Technology
Control 

Scenario

Control 

Technology 

Evaluated

Controlled 

SO2 Emission 

Rate1

(tons/year)

SO2 

Emission 

Reductions2

(tons/year)

Installed 

Capital Cost

Total 

Annualized 

Control 

Costs

Cost 

Effectiveness

(per ton SO2 

removed)

Energy 

Impact

(kW-hr/yr)

291 tons/yr PM2.5 27,130 to

243 tons/yr PM10 182.5 m

17,597 tons/yr GHG3

54 tons/yr PM2.5 639.5 to

52 tons/yr PM2.5 12.8 m

1,330 tons/yr GHG3

Current 

Allowable 

Emissions

Operating Limit of 3% Sulfur in Coke

7,076

Notes:

3 Greenhouse gas (GHG) emissions are presented as CO2 equivalent emissions. The GHG emission calculations are presented in Appendix E.

Non-A

Table 5-3

Summary of the Impacts Analysis for SO2 Control Scenarios

Alcoa Intalco Works

Ferndale, Washington

Collateral Increase 

in Other Pollutants

1 Emission rates include the potline primary control system, the potline secondary control system emissions, and the anode bake furnace emissions.2 Compared with current potential emissions.

12

LSFO Scrubber for PotlinesLSFO Scrubber for Anode Bake Furnace

854

6,904

6,223

172 $29,482,194

$234,531,049

6,570,000

$46,820,000 64,824,000

$6,277,000

$7,500

$36,400
LCC 

Coordinate 

X

LCC 

Coordinate 

Y

Stack 

Height

Base 

Elevation

Effective 

Stack 

Diameter

Exit 

Velocity

Exit 

Temperature

PM10 

Emission 

Rate

Filterable 

PM2.5 

Emission 

Rate

C

(km) (km) (m) (m) (m) (m/s) (°K) (g/s) (g/s) 

1 LSFO Scrubber for Potlines Potline Wet Scrubber2 -120.425 -15.316 38.1 59.0 8.1 18.3 310 0.00 17.8 

2 LSFO Scrubber for Anode Bake Furnace Anode Bake Furnace Wet Scrubber3 -121.018 -15.614 30.5 57.5 2.6 18.3 336 0.00 1.70 

Notes:

1 Source input data for all other sources are the same as listed in Table 4-1 through 4-4 for the baseline modeling.2 Potline wet scrubber source replaces sources DSA1, DSA2, DSB3, DSB4, DSC5, and DSC6 in Table 4-1 from the baseline modeling.3 Anode bake oven wet scrubber source replaces source BAKEOVEN in Table 4-1 from the baseline modeling.

Control 

Scenario

SO2 Control 

Technology Source Description

Table 5-4

Source Input Data for Post Control SO2 Modeling1

Alcoa Intalco Works

Ferndale, Washington
Modeled 

98th 

Percentile

Modeled 

98th 

Percentile

Mode

98th 

Percen

(deciview) (deciview) (decivi

Alpine Lakes Wilderness Area 0.158 0 0.147 0 0.12Glacier Peak Wilderness Area 0.190 0 0.163 0 0.12Mount Rainier National Park 0.108 0 0.107 0 0.08North Cascades National Park 0.198 0 0.212 0 0.17Olympic National Park 0.355 2 0.303 1 0.32Alpine Lakes Wilderness Area 0.723 22 0.729 18 0.62

Glacier Peak Wilderness Area 0.901 24 0.752 23 0.54

Mount Rainier National Park 0.648 11 0.565 9 0.41

North Cascades National Park 0.921 36 0.974 34 0.68

Olympic National Park 1.503 41 1.348 37 1.20

Alpine Lakes Wilderness Area 0.738 24 0.742 18 0.63

Glacier Peak Wilderness Area 0.916 24 0.769 25 0.55

Mount Rainier National Park 0.660 11 0.574 9 0.41

North Cascades National Park 0.936 36 0.986 35 0.69

Olympic National Park 1.527 41 1.369 37 1.22

Note:

Table 5-5

SO2 Post Control Visibility Modeling Results

Alcoa Intalco Works

Ferndale, Washington

Control 

Scenario

SO2 Control 

Technology 

Evaluated

Class I Area

2003

Number of 

Days 

Exceeding 

0.5 dv

2004

Number of 

Days 

Exceeding 

0.5 dv

Current 

Allowable 

Emissions

Operating Limit of 3% Sulfur in Coke

Modeled visibility impacts that exceed the 0.5 dv contribution threshold are presented in bold in this table.

LSFO Scrubber for Potlines 1

2 LSFO Scrubber for Anode Bake Furnace
APPENDICES 
APPENDIX A: 

BART MODELING RESULTS
APPENDIX B: 

BUSINESS CONFIDENTIAL INFORMATION
APPENDIX C: 

PRE-FEASIBILITY REPORT
APPENDIX D: 

WET SCRUBBER ECONOMIC AND ENERGY IMPACT
Potlines Anode Bake Furnace Vendor Quote #1 Vendor Quote #2 Average Potli

Reagent feed system 10% 0.33 0.80 $6,500,000 $8,200,000 $7,350,000 $7,894SO2 removal system 35% 0.50 0.80 $22,750,000 $28,700,000 $25,725,000 $28,54

Flue gas system 30% 0.50 0.80 $19,500,000 $24,600,000 $22,050,000 $24,46By-product handling system 10% 0.40 0.80 $6,500,000 $8,200,000 $7,350,000 $8,104General support equipment 15% 0.15 0.80 $9,750,000 $12,300,000 $11,025,000 $11,43

TOTAL $65,000,000 $82,000,000 $73,500,000 $80,44

Scaling of Capital Equipment Costs Based on Vendor Proposals

Intalco Works

Ferndale, Washington

Intalco 

Fraction of 

Total 

Equipment 

Cost

Scrubber Component

Scaling Equation 

Exponent Tennessee Potline Scrubber Equipment Costs

BART cost calculations 110607.xls-Capital equipment costs 
Potlines

Intalco Works

Ferndale, Washington

Value Notes/References

Capital Investment Costs

Direct Capital Costs (DCC)

Purchased Equipment Costs (PEC)

Adsorber vessels with internals $80,445,682 Based on vendor quotations for Tennessee Alcoa smelter, adjusted for 

scrubber exhaust gas flow rate, limestone consumption, and gypsum 

generation per Pre-feasability Report (Hatch 2007)

Pumps Included

Limestone prep Included

Dewatering systems Included

Fans Included

Inlet ductwork Included

Stacks Included

Continuous Emission Monitoring system (2 stacks) $80,000

Subtotal (EC) $80,525,682

Instrumentation $4,026,284 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of EC; adjusted 

from 10% since basic instrumentation is included in proposal)

Sales tax $5,234,169 State sales tax rate for Washington is 6.5%

Freight $4,026,284 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of EC)

Total Purchased Equipment Costs (PEC) $93,812,419

Direct Installation Costs (DIC)

Foundations and supports $11,257,490 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (12% of PEC)

Handling and erection $75,049,936 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (80% of PEC; adjusted 

from 40% to account for retrofit of existing plant and onsite fabrication)

Electrical $938,124 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Piping $28,143,726 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (30% of PEC)

Insulation $938,124 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Painting $938,124 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Total Direct Installation Costs (DIC) $117,265,524

Total Direct Capital Costs $211,077,944 Sum of PEC and DIC

Indirect Capital Costs (ICC)

Engineering $4,690,621 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of PEC; adjusted 

from 10% since vendor proposal includes an allowance for engineering)

Construction and field expenses $9,381,242 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (10% of PEC)

Contractor fees $4,690,621 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of PEC; adjusted 

from 10% based on assumption that vendor will oversee scrubber 

installation)

Start-up $938,124 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Performance test $938,124 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Contingencies $2,814,373 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (3% of PEC)

Total Indirect Capital Costs $23,453,105

Total Capital Investment Costs (TCIC) $234,531,049 Sum of DCC and ICC

References:

Hatch. 2007. SO 2 Scrubbing for the INTALCO Primary Aluminum Smelter: Pre-Feasibility Report . July 26.

USEPA. 2002. EPA Air Pollution Control Cost Manual , Sixth Edition. EPA/452/B-02-001. January.

Captial Investment Cost Analysis for SO2 Control Using a Wet Scrubber

BART cost calculations 110607.xls-Capital cost calcs (potlines) E N V I R O N
Potlines

Intalco Works

Ferndale, Washington

Value Units Notes/References

Annual Operation and Maintenance Costs

Direct Annual Costs (DAC)

Operating labor

Operator $324,120 Assumes $37 per hour with one full-time operator, 3 shifts per 

day

Supervisor $48,618 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (15% of 

operator costs)

Water $96,725

Water usage 500,000 gal/day Pre-feasability Report (Hatch 2007)

Cost of water $0.00053 $/gal Intalco controller

Limestone $470,052

Limestone usage 14,244 tons/yr Pre-feasability Report (Hatch 2007)

Cost of limestone $33 $/ton Assumes $28/ton for 8 mesh size limestone plus $5/ton for 

shipping by barge

Compressed air $18,922

Compressed air usage 150 scfm Pre-feasability Report (Hatch 2007)

Cost of compressed air $0.24 $/1000 scf Average compressed air generation cost for industrial facilities 

(http://www1.eere.energy.gov/industry/bestpractices/pdfs/com

pressed_air1.pdf) 

Gypsum disposal $3,933,809

Gypsum generation rate 6,194 lb/hr Pre-feasability Report (Hatch 2007)

Cost of gypsum disposal $145 $/ton Non-hazardous waste disposal and transportation costs

Maintenance

Labor $673,920 Assumes $45 per hour with 4 full-time maintenance personnel, 

one shift per day, 5 days per week and 1 maintenance 

personnel for all other shifts

Material $1,303,000 Cost for low sulfur boiler system with 1.7 macfm inlet/1.5 

macfm outlet, which is smaller than the potline system with 2.2 

macfm inlet/2.0 macfm outlet (Sargent & Lundy LLC 2003)

Electricity $3,409,742

Electricity usage 7,400 kWh/hr Pre-feasability Report (Hatch 2007)

Electricity cost $0.0526 $/kWh Facility average power rate for 2007 (Intalco controller)

Total Direct Annual Costs $10,278,908

Indirect Annual Costs (IAC)

Overhead $1,409,795 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (60% of total 

labor and maintenance material costs)

General and administrative costs $4,690,621

USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (2% of TCIC)

Property tax $2,345,310

USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Insurance $2,345,310

USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Total Indirect Annual Costs $10,791,037 Sum of PEC and DIC

Total Annual Operating and Maintenance Costs $21,069,945 Sum of DAC and IAC

References:

Hatch. 2007. SO 2 Scrubbing for the INTALCO Primary Aluminum Smelter: Pre-Feasibility Report . July 26.

Sargent & Lundy LLC. 2003. Wet Flue Gas Desulfurization Technology Evaluation . Prepared for National Lime Association. January.

USEPA. 2002. EPA Air Pollution Control Cost Manual , Sixth Edition. EPA/452/B-02-001. January.

Operation and Maintenance Cost Analysis for SO2 Control Using a Wet Scrubber

BART cost calculations 110607.xls-O&M cost calcs (potlines) E N V I R O N
Installation of Wet Scrubber on Potline Exhaust

Reference

Potline hooding capture efficiency 95%Total potline uncontrolled SOx emission rate 37,780 lb/day Total potline SOx emission limit

Primary potline control system uncontrolled SOx emission rate 35,891 lb/day Calculated based on potline hooding capture e

SOx control efficiency 95%

Controlled SOx emission rate 1,795 lb/day

Uncontrolled annual SOx emissions 6,550 tpy

Controlled annual SOx emissions 328 tpy

SOx reduction 6,223 tpy

Direct capital costs (DCC) 211,077,944 $ Indirect capital costs (ICC) 23,453,105 $ Total capital costs 234,531,049 $ Interest rate 7% USEPA 2002, Section 1, Chapter 2.4.2Period of annualization 15 years AssumptionCapital recovery discount factor 0.11 USEPA 2002, Section 1, Chapter 2.4.4.4, EquAnnualized capital cost 25,750,000 $ USEPA 2002, Section 1, Chapter 2.4.4.4, Equ

Operating labor costs 324,120 $ Supervisory labor costs 48,618 $ Maintenance labor costs 673,920 $ Maintenance material costs 1,303,000 $ Electricity costs 3,409,742 $ Water costs 96,725 $ Limestone costs 470,052 $ Compressed air costs 18,922 $ Gypsum disposal costs 3,933,809 $ Overhead 1,409,795 $ Property tax 2,345,310 $ Insurance 2,345,310 $ General and administrative costs 4,690,621 $ Total annual cost estimate 46,820,000 $ Cost of option per ton SO x reduced $ 7,500

BART cost calculations 110607.xls-Potline scrubber cost summary 
Captial Investment Cost Analysis for SO2 Control Using a Wet Scrubber

Anode Bake Furnace

Intalco Works

Ferndale, Washington

Value Notes/References

Capital Investment Costs

Direct Capital Costs (DCC)

Purchased Equipment Costs (PEC)

Adsorber vessels with internals $10,042,642 Based on vendor quotations for Tennessee Alcoa smelter, adjusted for 

exhaust gas flow rate per Pre-feasability Report (Hatch 2007)

Pumps Included

Limestone prep Included

Dewatering systems Included

Fans Included

Inlet ductwork Included

Stacks Included

Continuous Emission Monitoring system (2 stacks) $80,000

Subtotal (EC) $10,122,642

Instrumentation $506,132 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of EC; adjusted 

from 10% since basic instrumentation is included in proposal)

Sales tax $657,972 State sales tax rate for Washington is 6.5%

Freight $506,132 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of EC)

Total Purchased Equipment Costs (PEC) $11,792,878

Direct Installation Costs (DIC)

Foundations and supports $1,415,145 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (12% of PEC)

Handling and erection $9,434,302 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (80% of PEC; adjusted 

from 40% to account for retrofit of existing plant and onsite fabrication)

Electrical $117,929 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Piping $3,537,863 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (30% of PEC)

Insulation $117,929 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Painting $117,929 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Total Direct Installation Costs (DIC) $14,741,097

Total Direct Capital Costs $26,533,975 Sum of PEC and DIC

Indirect Capital Costs (ICC)

Engineering $589,644 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of PEC; adjusted 

from 10% since vendor proposal includes an allowance for engineering)

Construction and field expenses $1,179,288 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (10% of PEC)

Contractor fees $589,644 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of PEC; adjusted 

from 10% based on assumption that vendor will oversee scrubber 

installation)

Start-up $117,929 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Performance test $117,929 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Contingencies $353,786 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (3% of PEC)

Total Indirect Capital Costs $2,948,219

Total Capital Investment Costs (TCIC) $29,482,194 Sum of DCC and ICC

References:

Hatch. 2007. SO 2 Scrubbing for the INTALCO Primary Aluminum Smelter: Pre-Feasibility Report . July 26.

USEPA. 2002. EPA Air Pollution Control Cost Manual , Sixth Edition. EPA/452/B-02-001. January.

BART cost calculations 110607.xls-Capital cost calcs (ABF) E N V I R O N
Operation and Maintenance Cost Analysis for SO2 Control Using a Wet Scrubber

Anode Bake Furnace

Intalco Works

Ferndale, Washington

Value Units Notes/References

Annual Operation and Maintenance Costs

Direct Annual Costs (DAC)

Operating labor

Operator $324,120 Assumes $37 per hour with one full-time operator, 3 shifts per 

day

Supervisor $48,618 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (15% of 

operator costs)

Water $6,771

Water usage 35,000 gal/day Pre-feasability Report (Hatch 2007)

Cost of water $0.00053 $/gal Intalco controller

Limestone $11,286

Limestone usage 342 tons/yr Pre-feasability Report (Hatch 2007)

Cost of limestone $33 $/ton Assumes $28/ton for 8 mesh size limestone plus $5/ton for 

shipping by barge

Compressed air $6,307

Compressed air usage 50 scfm Pre-feasability Report (Hatch 2007)

Cost of compressed air $0.24 $/1000 scf Average compressed air generation cost for industrial facilities 

(http://www1.eere.energy.gov/industry/bestpractices/pdfs/com

pressed_air1.pdf) 

Gypsum disposal $92,725

Gypsum generation rate 146 lb/hr Pre-feasability Report (Hatch 2007)

Cost of gypsum disposal $145 $/ton Non-hazardous waste disposal and transportation costs

Maintenance

Labor $336,960 Assumes $45 per hour with 2 full-time maintenance personnel, 

one shift per day, 5 days per week and a half-time maintenance 

personnel equivalent for all other shifts

Material $163,796 Calculated based on estimated maintenance material costs for 

potline scrubber and ratio of purchased equipment costs for the 

anode bake furnace and potline scrubbers

Electricity $345,582

Electricity usage 750 kWh/hr Pre-feasability Report (Hatch 2007)

Electricity cost $0.0526 $/kWh Facility average power rate for 2007 (Intalco controller)

Total Direct Annual Costs $1,336,165

Indirect Annual Costs (IAC)

Overhead $524,097 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (60% of total 

labor and maintenance material costs)

General and administrative costs $589,644

USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (2% of TCIC)

Property tax $294,822

USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Insurance $294,822

USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Total Indirect Annual Costs $1,703,384 Sum of PEC and DIC

Total Annual Operating and Maintenance Costs $3,039,549 Sum of DAC and IAC

References:

Hatch. 2007. SO 2 Scrubbing for the INTALCO Primary Aluminum Smelter: Pre-Feasibility Report . July 26.

USEPA. 2002. EPA Air Pollution Control Cost Manual , Sixth Edition. EPA/452/B-02-001. January.

BART cost calculations 110607.xls-O&M cost calcs (ABF) E N V I R O N
Installation of Wet Scrubber on Anode Bake Furnace Exhaust

Reference

Uncontrolled SOx emission rate 994 lb/day

SOx control efficiency 95%

Controlled SOx emission rate 50 lb/day

Uncontrolled annual SOx emissions 181 tpy

Controlled annual SOx emissions 9 tpy

SOx reduction 172 tpy

Direct capital costs (DCC) 26,533,975 $ Indirect capital costs (ICC) 2,948,219 $ Total capital costs 29,482,194 $ Interest rate 7% USEPA 2002, Section 1, Chapter 2.4.2Period of annualization 15 years AssumptionCapital recovery discount factor 0.11 USEPA 2002, Section 1, Chapter 2.4.4.4, Equation 2.8aAnnualized capital cost 3,237,000 $ USEPA 2002, Section 1, Chapter 2.4.4.4, Equation 2.8

Operating labor costs 324,120 $ Supervisory labor costs 48,618 $ Maintenance labor costs 336,960 $ Maintenance material costs 163,796 $ Electricity costs 345,582 $ Water costs 6,771 $ Limestone costs 11,286 $ Compressed air costs 6,307 $ Gypsum disposal costs 92,725 $ Overhead 524,097 $ Property tax 294,822 $ Insurance 294,822 $ General and administrative costs 589,644 $ Total annual cost estimate 6,277,000 $ Cost of option per ton SO x reduced $ 36,400

BART cost calculations 110607.xls-Furnace scrubber cost summary 
APPENDIX E: 

GREENHOUSE GAS EMISSION CALCULATIONS
 E-1 

BART Determination 

Alcoa Intalco Works 

Ferndale, Washington 

Greenhouse Gas Emission Calculations 

Greenhouse gases (GHGs) are gaseous compounds that are considered to act as heat trapping 

constituents of the atmosphere. Although there are many gases that may trap heat in the 

atmosphere, there are six GHGs recognized by international and domestic regulations on climate 

change: carbon dioxide (CO2), nitrous oxide (N2O), methane, hydrofluorocarbons (HFCs), 

chlorinated fluorocarbons (CFCs), and sulfur hexafluoride. More than 80% of the global warming 

potential results from CO2 emissions. 

The proposed sulfur dioxide (SO2) control devices will contribute to the facility’s overall emissions 

of GHGs via three mechanisms: (1) as a byproduct of the reaction chemistry in the scrubbers, (2) as 

indirect emissions from the generation of electricity required to power the scrubbing systems, and 

(3) as direct emissions from vehicle travel for the additional personnel that will be required at the 

facility to maintain and operate the scrubbing systems. 

The estimate of carbon dioxide emissions resulting from the reaction of limestone with the sulfur 

dioxide in the exhaust streams is based on the theoretical reaction chemistry, assuming no other 

byproducts resulting from incomplete reaction. Consistent with the BART analysis, we assumed 

that 95% of the incoming sulfur dioxide reacts with the limestone, and hence is removed from the 

exhaust stream. There are three reactions taking place in the scrubber: 

1) Dissolution of the limestone in the scrubbing water: 

CaCO3 + H2O Æ Ca+2 + HCO3

-

 + OH2) Dissolution of the sulfur dioxide in the scrubbing water: 

SO2 + H2O Æ 2H+

 + SO3

-2

3) Oxidation of the sulfite ions to sulfate ions (and hence, formation of gypsum or calcium sulfate): 

Ca+2 + HCO3

-

 + OH- + 2H+ + SO3

-2 + 1⁄2 O2 Æ CaSO4 + CO2 +2 H2O 

Consistent with the chemical balance shown above, for every mole of SO2 reacted, a mole of 

carbon dioxide is formed. 

The inlet sulfur dioxide molar flowrate was estimated based on design parameters provided by 

Hatch Associates1. Assuming a minimum 95% sulfur dioxide control efficiency (that is, assuming 

that 95% of the sulfur dioxide reacts with the limestone), the mass of carbon dioxide evolved was 

calculated based on the reaction chemistry presented above. 

 

1

 Hatch Associates. 2007. Pre-Feasibility Report – SO2 Scrubbing for the INTALCO Primary Aluminum Smelter. 

November 5. Tables 3 and 6 (potline exhaust and anode baking furnace exhaust, respectively). 
 E-2 

The implementation of the proposed scrubbing systems would also generate GHGs indirectly, as a 

result of consuming electricity. The generation of electricity at some off-site location would 

produce GHGs. The methodology described in the California Climate Action Registry General 

Reporting Protocol (CCARGRP)2

, for estimating indirect emissions of GHGs from electricity use 

was followed. Based on design specifications provided by Hatch Associates3, the daily electricity 

usage of each scrubber (potline fumes scrubber and the anode bake furnace scrubber) were 

multiplied by a state-specific carbon dioxide emission factor. The state-specific emission factor 

was found in the USEPA Emissions and Generation Resource Integrated Database for 2006

(eGrid2006)4 for Washington state. To estimate the emissions of nitrous oxide and methane (two 

minor GHG components from combustion sources), the default emission factors provided in the 

CCARGRP5

 were used. To convert the estimated nitrous oxide and methane emissions to carbon 

dioxide equivalents, the CCARGRP provides an estimate of each compound’s global warming 

potential (GWP)6

. For example, methane has a GWP of 21 times that of carbon dioxide; therefore, 

to convert the methane emission rate to carbon dioxide equivalents, we multiply the methane 

emission rate by its GWP. 

The last potential source of GHGs resulting from the implementation of the proposed scrubbing 

systems is from vehicle travel to and from the facility by additional personnel necessary for the 

operation and maintenance of the scrubbing systems. Based on facility estimates, the potline fumes 

scrubbing system would require nine additional employees per day on weekdays and six additional 

personnel per day on weekends. Similarly, the anode baking furnace scrubbing system would 

require six additional employees per day on weekdays and 4.5 additional personnel equivalents per 

day on weekends. It was assumed that each person would drive a roundtrip distance of 20 miles 

per day. This is approximately the roundtrip distance between the facility and downtown 

Bellingham, Washington. The emission estimates of carbon monoxide, nitrous oxide, and methane 

in the vehicle exhaust were based on assuming an average fuel economy. The fleet average (1988 

to 2007) fuel economy from the USEPA7

 was used. The emission factor for carbon dioxide was 

provided in the CCARGRP for non-California gasoline8. The emission factors for nitrous oxide 

and methane from vehicles were based on the average of the 1988 to present emission factors 

provided in the CCARGRP9

. To convert the nitrous oxide and methane emission rates to carbon 

dioxide equivalents, the GWP for each compound was applied as discussed above. 

 

2

 California Climate Action Registry. 2007. California Climate Action Registry General Reporting Protocol 

(CCARGRP): Reporting Entity-Wide Greenhouse Gas Emissions. Version 2.2. March. Chapter 6. 3

 Hatch Associates. 2007. Pre-Feasibility Report – SO2 Scrubbing for the INTALCO Primary Aluminum Smelter. 

November 5. Tables 5 and 8 (potline fumes scrubbing and anode baking furnace scrubbing, respectively). 4

 United States Environmental Protection Agency (USEPA). 2007. Emissions and Generation Resource Integrated 

Database for 2006 (eGrid2006). Version 2.1. April. Year 2004 summary tables. 

5

 California Climate Action Registry. 2007. California Climate Action Registry General Reporting Protocol 

(CCARGRP): Reporting Entity-Wide Greenhouse Gas Emissions. Version 2.2. March. Table C-2 6

 Ibid. Table III.6-1. 

7

 United States Environmental Protection Agency (USEPA). 2007. Light-Duty Automotive Technology and Fuel 

Economy Trends: 1975 to 2007 (Table 1 – Cars and Trucks). 

8

 California Climate Action Registry. 2007. California Climate Action Registry General Reporting Protocol 

(CCARGRP): Reporting Entity-Wide Greenhouse Gas Emissions. Version 2.2. March. Table C-3. 9

 Ibid. Table C-4 (used weighted average of the factors provided for various spans of model years). 
 E-3 

The GHG emission calculations described above are presented in the attached tables. The total 

GHGs (in carbon dioxide equivalents) generated by the implementation of the proposed scrubbing 

system for the potline fumes was estimated to be 96,441 pounds per day, or 17,598 tons per year. 

The total GHGs (in carbon dioxide equivalents) generated by the implementation of the proposed 

scrubbing system for the anode baking furnace was estimated to be 7,298 pounds per day, or 1,330 

tons per year. 
Greenhouse Gases Emissions

Intalco (Ferndale, WA)

Scope :

Assumptions:

Sources of Greenhouse Gases :

Summary of Potline Wet Scrubber GHG Emission Estimates :

Mass of CO2 evolved from scrubbing potroom emissions 31,969 lb/day

Mass of GHGs (in CO2 equivalents) evolved from electricity production for scrubbing system 64,294 lb/day

Mass of GHGs (in CO2 equivalents) evolved from vehicle travel for additional personnel 177.9 lb/day

96,441 lb/day

17,597 tons/yr

Summary of Anode Bake Furnace Wet Scrubber GHG Emission Estimates :

Mass of CO2 evolved from scrubbing anode bake furnace emissions 663 lb/day

Mass of GHGs (in CO2 equivalents) evolved from electricity production for scrubbing system 6,516 lb/day

Mass of GHGs (in CO2 equivalents) evolved from vehicle travel for additional personnel 118.6 lb/day

7,298 lb/day

1,330 tons/yr

TOTAL GHGs (CO2 equivalents)

TOTAL GHGs (CO2 equivalents)

- The addition of personnel as a result of the operation of the scrubbing systems (vehicle travel)

Calculation of greenhouse gases from the implementation of a flue gas desulfurization system. There will be one 

scrubbing system for the potrooms and one for the anode baking furnace. The scrubbing system consists of a 

limestone-gypsum forced oxidation (LSFO) process.

CO2 is the primary greenhouse gas evolved. Other components, such as methane or nitrous oxide are in de minimus 

quantities. These will be included where there is sufficient information for their estimate.

- Reaction chemistry of the limestone and sulfur dioxide (LSFO)

- Energy consumption of the scrubbing systems
GHG Emissions from Scrubbing Potline Emissions

Scrubbing Reaction Chemistry:1) CaCO3 + H2O ------> Ca+2 + HCO3- + OH2) SO2 + H2O -----------> 2H+ + SO3-23) Ca+2 + HCO3- + OH- + SO3-2 + 2H+ + 1/2 O2 ----------------> CaSO4 + CO2 + 2H2O

So, for every one mole of SO2 (64 grams) removed, one mole of CO2 (44 grams) is evolved.

Based on the final Hatch pre-feasibility report (dated November 5, 2007):

Parameter Reference

SO2 concentration 300 mg/Nm3 Hatch, Table 3

Flowrate 1,814,880 scfm Hatch, Table 3

51,394 m3/min

SO2 at inlet of FGD system 257.0 grams/second Calculated, based on FGD inlet flow characteristics presented in Hatch, Table 

4.02 moles SO2/second Based on molar mass of SO2 of 64 grams/mole

Removal efficiency 95% minimum Hatch, Table 4Moles of SO2 reacted 3.81 moles SO2/second

Moles of CO2 evolved 3.81 moles CO2/second

Mass of CO2 evolved 167.8 grams CO2/second Based on molar mass of CO2 of 44 grams/mole

14,500,691 grams CO2/day

31,969 lb CO2/day

Value
GHG Emissions from Scrubbing Anode Baking Furnace Emissions

Scrubbing Reaction Chemistry:

1) CaCO3 + H2O ------> Ca+2 + HCO3

-

 + OH -

2) SO2 + H2O -----------> 2H+ + SO3

-2

3) Ca+2 + HCO3

-

 + OH - + SO3

-2 + 2H+

 + 1/2 O2 ----------------> CaSO4 + CO2 + 2H2O

So, for every one mole of SO2 (64 grams) removed, one mole of CO2 (48 grams) is evolved.

Based on the final Hatch pre-feasibility report (dated November 5, 2007):

Parameter Reference

SO2 at inlet of FGD system 5.33 grams/second Hatch, Table 6

0.083 moles SO2/second Based on molar mass of SO2 of 64 grams/mole

Removal efficiency 95% minimum Hatch, Table 7

Moles of SO2 reacted 0.079 moles SO2/second

Moles of CO2 evolved 0.079 moles CO2/second

Mass of CO2 evolved 3.5 grams CO2/second Based on molar mass of CO2 of 44 grams/mole

300,772 grams CO2/day

663 lb CO2/day

Value
GHGs resulting from electricity generation associated with potline scrubber system1

Parameters ReferenceElectricity usage for potline wet scrubber 7,400 kWh/h Hatch, Table 5Electricity usage for potline wet scrubber 177,600 kWh/day Assumes continuous operation of wet scrubberN2O global warming potential (GWP) 310 Table III.6.1 - CCARGRP

Methane GWP 21 Table III.6.1 - CCARGRPEmission Factors Reference

CO2 360 lb/MWh Emission factors for Washington state (eGrid 2006 Version 2.1, A

CO2 0.36 lb/kWh

N2O 0.004 lb/MWh Default emission factors for N2O and methane for Washington sta

Methane 0.037 lb/MWh Default emission factors for N2O and methane for Washington staEmission Estimates

CO2 63,936 lb/day

N2O 0.71 lb/day

Methane 6.57 lb/dayConversion of non-CO2 GHGs to CO2 equivalents

CO2 63,936 lb/day

N2O - CO2 equivalents 220 lb/day

Methane - CO2 equivalents 138 lb/day

Total CO2 equivalents 64,294 lb/day

Notes:

1Based on methodology described in the California Climate Action Registry General Reporting Protocol (CCARGRP) (March 2007) and th

Emissions & Generation Resource Integrated Database (eGrid2006).
GHGs resulting from electricity generation associated with anode bake furnace scrubber system1

Parameters ReferenceElectricity usage for anode bake furnace wet scrubber 750 kWh/h Hatch, Table 8Electricity usage for anode bake furnace wet scrubber 18,000 kWh/day Assumes continuous operation of wet scrubberN2O global warming potential (GWP) 310 Table III.6.1 - CCARGRP

Methane GWP 21 Table III.6.1 - CCARGRPEmission Factors Reference

CO2 360 lb/MWh Emission factors for Washington state (eGrid 2006 Version 2.1, A

CO2 0.36 lb/kWh

N2O 0.004 lb/MWh Default emission factors for N2O and methane for Washington st

Methane 0.037 lb/MWh Default emission factors for N2O and methane for Washington stEmission Estimates

CO2 6,480 lb/day

N2O 0.07 lb/day

Methane 0.67 lb/dayConversion of non-CO2 GHGs to CO2 equivalents

CO2 6,480 lb/day

N2O - CO2 equivalents 22 lb/day

Methane - CO2 equivalents 14 lb/day

Total CO2 equivalents 6,516 lb/day

Notes:

1Based on methodology described in the California Climate Action Registry General Reporting Protocol (CCARGRP) (March 2007) and t

Emissions & Generation Resource Integrated Database (eGrid2006).
GHGs resulting from vehicle travel for additional personnel associated with potline scrubber system1

Parameters ReferenceAdditional operating personnel 3 One additional full-time operator per shift, three shifts per day (assumption)Additional maintenance personnel (weekdays) 6 Four additional full-time maintenance personnel, one shift per day, plus one additional fulltime maintenance personnel for off-shifts (assumption)Additional maintenance personnel (weekends) 3 One additional full-time maintenance personnel for off-shifts (assumption)Total additional personnel (weekdays) 9Total additional personnel (weekends) 6Daily round trip distance 20 miles/trip Assumption (distance from plant to downtown Bellingham, WA is approximately 10 miles)Total daily mileage (weekdays) 180 miles/dayTotal daily mileage (weekends) 120 miles/dayAverage fuel economy 20.3 miles/gallon Fleet average (1988 to 2007 model years); USEPA, Light-Duty Automotive Technology 

and Fuel Economy Trends: 1975 to 2007, Table 1 (Cars and Trucks)

N2O global warming potential (GWP) 310 Table III.6.1 - CCARGRPMethane GWP 21 Table III.6.1 - CCARGRPEmission Factors ReferenceCO2 emission factor 8.78 kg/gallon Non-CA gasoline; Table C.3, CCARGRPN2O emission factor 0.050 grams/mile Weighted average of 1988 to present automobile model years; Table C.4, CCARGRPMethane emission factor 0.049 grams/mile Weighted average of 1988 to present automobile model years; Table C.4, CCARGRPEmission EstimatesCO2 (weekdays) 171.4 lb/dayN2O (weekdays) 0.020 lb/dayMethane (weekdays) 0.019 lb/dayCO2 (weekends) 114.3 lb/dayN2O (weekends) 0.013 lb/dayMethane (weekends) 0.013 lb/dayConversion of non-CO2 GHGs to CO2 equivalentsCO2 (weekdays) 171.4 lb/dayN2O - CO2 equivalents (weekdays) 6.2 lb/dayMethane - CO2 equivalents (weekdays) 0.4 lb/day

Total CO2 equivalents (weekdays) 177.9 lb/day

CO2 (weekends) 114.3 lb/day

N2O - CO2 equivalents (weekends) 4.1 lb/dayMethane - CO2 equivalents (weekends) 0.3 lb/day

Total CO2 equivalents (weekends) 118.6 lb/day

CO2 (annual) 28.2 tons/yr

N2O - CO2 equivalents (annual) 1.0 tons/yrMethane - CO2 equivalents (annual) 0.1 tons/yr

Total CO2 equivalents (annual) 29.3 tons/yr

Notes:

1Based on methodology described in the California Climate Action Registry General Reporting Protocol (CCARGRP) (March 2007).
GHGs resulting from vehicle travel for additional personnel associated with anode bake furnace scrubber system1

Parameters ReferenceAdditional operating personnel 3 One additional full-time operator per shift, three shifts per day (assumption)Additional maintenance personnel (weekdays) 3 Two additional full-time maintenance personnel, one shift per day, plus one additional halftime equivalent maintenance personnel for off-shifts (assumption)Additional maintenance personnel (weekends) 1.5 One additional half-time equivalent maintenance personnel for off-shifts (assumption)Total additional personnel (weekdays) 6Total additional personnel (weekends) 4.5Daily round trip distance 20 miles/trip Assumption (distance from plant to downtown Bellingham, WA is approximately 10 miles)Total daily mileage (weekdays) 120 miles/dayTotal daily mileage (weekends) 90 miles/dayAverage fuel economy 20.3 miles/gallon Fleet average (1988 to 2007 model years); USEPA, Light-Duty Automotive Technology 

and Fuel Economy Trends: 1975 to 2007, Table 1 (Cars and Trucks)

N2O global warming potential (GWP) 310 Table III.6.1 - CCARGRPMethane GWP 21 Table III.6.1 - CCARGRPEmission Factors ReferenceCO2 emission factor 8.78 kg/gallon Non-CA gasoline; Table C.3, CCARGRPN2O emission factor 0.050 grams/mile Weighted average of 1988 to present automobile model years; Table C.4, CCARGRPMethane emission factor 0.049 grams/mile Weighted average of 1988 to present automobile model years; Table C.4, CCARGRPEmission EstimatesCO2 (weekdays) 114.3 lb/dayN2O (weekdays) 0.013 lb/dayMethane (weekdays) 0.013 lb/dayCO2 (weekends) 85.7 lb/dayN2O (weekends) 0.0099 lb/dayMethane (weekends) 0.0096 lb/dayConversion of non-CO2 GHGs to CO2 equivalentsCO2 (weekdays) 114.3 lb/dayN2O - CO2 equivalents (weekdays) 4.1 lb/dayMethane - CO2 equivalents (weekdays) 0.3 lb/day

Total CO2 equivalents (weekdays) 118.6 lb/day

CO2 (weekends) 85.7 lb/day

N2O - CO2 equivalents (weekends) 3.1 lb/dayMethane - CO2 equivalents (weekends) 0.2 lb/day

Total CO2 equivalents (weekends) 89.0 lb/day

CO2 (annual) 19.3 tons/yr

N2O - CO2 equivalents (annual) 0.7 tons/yrMethane - CO2 equivalents (annual) 0.05 tons/yr

Total CO2 equivalents (annual) 20.0 tons/yr

Notes:

1Based on methodology described in the California Climate Action Registry General Reporting Protocol (CCARGRP) (March 2007).
 

 

Alcoa Primary Metals 

USA 

Pre-Feasibility Report 

 

SO2 Scrubbing for the INTALCO Primary 

Aluminum Smelter 

H-325640 

 2 

November 5, 2007 
Alcoa Primary Metals - SO2 Scrubbing for the INTALCO Primary Aluminum Smelter 

Pre-Feasibility Report 

ISO 9001 PR325640.10001, Rev. 2

325640-RPT-CA01-10001.Doc © Hatch 2006/03 a

Project Report 

PR325640.10001 

Rev. 2, Page 1

November 5, 2007 

Alcoa Primary Metals 

SO2 Scrubbing for the INTALCO Primary 

Aluminum Smelter 

 DISTRIBUTION 

Alcoa Hatch 

 Michael Palazzolo Martin Desmeules 

James Schon Don Wilson 

 Stephan Broek 

Pre-Feasibility Report 

Table of Contents 

1. Summary ................................................................................................................................................. 2

2. Introduction ............................................................................................................................................ 4

2.1 Process Selection ........................................................................................................................... 4

2.2 FGD System Configuration............................................................................................................. 4

3. FGD System for the Potrooms................................................................................................................. 6

3.1 Design Basis................................................................................................................................... 6

3.2 Process description ........................................................................................................................ 7

3.3 Mass balance of an FGD system treating the fumes from the potrooms........................................... 8

3.4 Consumables ............................................................................................................................... 10

3.5 Scope of work.............................................................................................................................. 10

4. FGD System for the Baking Furnace...................................................................................................... 12

4.1 Design basis................................................................................................................................. 12

4.2 Process description ...................................................................................................................... 13

4.3 Mass balance for an FGD system to treat the fumes from the baking furnace................................ 14

4.4 Consumables ............................................................................................................................... 15

4.5 Scope of work.............................................................................................................................. 15

5. Capital cost estimates............................................................................................................................ 18

5.1 Methodology ............................................................................................................................... 18

5.2 Cost estimate for the potline FGD system..................................................................................... 20

5.3 Cost estimate for the baking furnace FGD system......................................................................... 20
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1. Summary 

This report is a pre-feasibility study for the implementation of flue gas desulphurisation (FGD) 

systems at the primary aluminum smelter of Intalco Works in Ferndale, Washington. The study focus 

is on controlling the SO2 emissions from the potrooms and from the baking furnace. The target 

removal is set for 95% of the released SO2 at the emissions sources. 

For both solutions the well known Limestone/Gypsum Forced Oxidation (LSFO) process is applied. 

This widely used process uses limestone as a reagent and produces gypsum as a by-product. This 

product can either be reused or safely stored in a landfill. 

Potlines 

For the potlines the selected configuration is a gas collection system that connects to each dry 

scrubbing system and redirects all fumes to a central FGD system. The FGD system comprises of 

two large open spray tower type absorbers in which the fumes are washed and cleaned. One such 

unit is operating while the second is on standby. The limestone handling as well as the gypsum 

recovery is done in a single plant serving both absorbers. Appropriate redundancy is built-in to 

ensure the 100% availability that is required in a smelter that operates 24 hrs a day, every day of the 

year. 

The FGD system is designed to handle 1,814,880 SCFM of fumes from the potrooms. This equates to 

an annual SO2 emission reduction of 7,875 tpa. The associated limestone consumption is 14,244 tpa 

while the water intake is 500,000 US Gallons per day. The annual gypsum production is 27,130 ton. 

The cost estimate is a factored cost estimate using information derived from previous studies and cost 

databases. The following table presents the results for the potline FGD system. 

Table 1: Capital cost estimate for the potline FGD system 

All values in million USD

Equipment Installation Subtotal

Reagent feed system $6.98 $6.98 $13.96

SO2 removal system $25.24 $25.24 $50.49

Flue gas system $21.64 $21.64 $43.27

Byproduct handling $7.17 $7.17 $14.33

General support equipment $10.11 $10.11 $20.23

TOTAL PROCESS CAPITAL $71.14 $71.14 $142.28

POTLINE FGD

Anode Baking Furnace 

A smaller source of SO2 emissions are the fumes from the anode baking furnace. In this case a single 

collector duct is tied into the existing dry scrubbing system to connect to the FGD system. This FGD 

system is much smaller but has the same configuration as the potline FGD system. It provides for 

100% available scrubbing. 
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The FGD system is designed to handle 172,510 SCFM of fumes from the potrooms. This equates to 

an annual SO2 emission reduction of 175 tpa. The associated limestone consumption is 342 tpa 

while the water intake is 35,000 US Gallons per day. The annual gypsum production is 640 ton. 

The cost estimate is a factored cost estimate using information derived from previous studies and cost 

databases. The following table presents the results for the potline FGD system. 

Table 2: Capital cost estimate for the baking furnace FGD system 

All values in million USD

Equipment Installation Subtotal

Reagent feed system $0.36 $0.36 $0.72

SO2 removal system $4.13 $4.13 $8.25

Flue gas system $3.54 $3.54 $7.07

Byproduct handling $0.36 $0.36 $0.71

General support equipment $0.50 $0.50 $1.01

TOTAL PROCESS CAPITAL $8.88 $8.88 $17.76

BAKING FURNACE FGD
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2. Introduction 

This report presents a pre-feasibility study on the implementation of FGD systems at the Intalco 

primary aluminum smelter in Ferndale, Washington. 

The aluminum smelter has two primary sources of sulphur emissions, one is the pot rooms and the 

second is the anode baking furnace. This report includes the design and cost information on a 

dedicated FGD system for each of these main sources. 

2.1 Process Selection 

In previous studies Best Available Technologies were identified. For studies at the Alcoa Tennessee 

smelter the limestone-gypsum forced oxidation (LSFO) process was selected for further evaluation . 

2.2 FGD System Configuration 

2.2.1 Pot room system 

The FGD system is designed to capture fumes from the potrooms under fully operational conditions. 

A comprehensive evaluation was done to see what configuration would be more effective: a set of 

scrubbing towers per potline (equal to two potrooms) or one central system with long collector ducts 

feeding into the central system. 

Two main criteria were used to decide what configuration to apply: 1) The sum of all fumes must be 

treated in one scrubbing tower and 2) maintenance must be minimized. 

The first criteria was met after calculations showed that the sum of all flows would result in a 

scrubbing tower with a diameter of 60 feet. A large diameter tower is not uncommon and several 

FGD wet scrubbing towers with diameters of this size have been constructed world-wide. Having 

many smaller scrubbing towers versus one large tower design combined with collector ducts made 

of regular gauge steel is considered to be less cost effective than the latter case. 

The second criteria concerns maintenance. The LSFO process basically is the circulation of a slurry 

of water, limestone and gypsum. It is abrasive and to a certain extent corrosive. Therefore, a lot of 

maintenance activity is associated with the circulation pumps and the scrubbing tower. Based on 

the design criteria of minimized maintenance, the selected system configuration was based on a 

single large scrubbing tower that would treat all of the pot room ventilation flows. Potroom flow 

would be combined into a single stream by a network of ducts, collecting fume from the current dry 

gas cleaning systems. . 

An additional consideration was the continuous operation of a smelter. A single scrubbing tower 

must be taken down for service five to ten days per year (conservatively). This means that during 

periods of maintenance, there would be no scrubbing of SO2 if a single scrubbing tower were 

installed. To provide 100 percent scrubbing availability during maintenance periods, a second 

scrubbing tower of the same size would be added to the design to ensure continuous SO2 treatment 

during periods when the first scrubbing tower is taken out of service. 
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2.2.2 Baking furnace system 

The FGD system for the baking furnace is of a simpler concept. The baking furnace is currently 

operated with an evaporative cooling tower followed by a dry gas cleaning system. The new FGD 

system will be connected downstream to the dry gas cleaning unit. 

Anode Baking 

Furnace

Evaporative gas cooler

Dry gas cleaning

(New) SO2 Control system

Figure 1: Overall gas cleaning concept for the anode baking furnace. 
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3. FGD System for the Potrooms 

3.1 Design Basis 

The design basis for both scrubbing systems has been based on technical process information 

provided by Alcoa. The information is based on actual operating conditions and operating 

information for Intalco Works. 

The following table presents the design basis for the FGD system serving the potlines. 

Table 3: Design basis for the potline FGD system at Intalco Works 

Design parameter Unit Value 

Number of potrooms in service - 6 

Number of GTCs per potroom - 1 

Total number of GTCs connected - 6 

No. of reduction cells per potroom - 120 

Ventilation flow for one reduction cell ACFM 3,000 (@212 °F) 

 SCFM (70 °F) 2,354 

Air addition in each dry gas cleaning unit SCFM 20,000 (Estimate) 

Total flow of fumes to the FGD system SCFM 1,814,880 

Nominal fume temperature °F 180 

Composition of the fumes at the inlet of the FGD system 

Sulphur dioxide (SO2) ppmv 105 (300 mg/Nm3) 

Hydrogen fluoride (HFg) mg/Nm3 5 

Water vapour (H2O) vol% 3 

Particulates mg/Nm3 10 

In addition, the following system requirements are applied in the design of the system. 

Table 4: Design requirements 

Aspect Unit Requirement 

Desulphurization efficiency % Min. 95 

Removal efficiency of particulates and 

fluorides 

- No increment 

Residual droplets mg/Nm3 Max. 100 
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Spare scrubbing capacity % 100 

(1 full scrubbing tower standby/no spare spray layers inside 

one scrubbing tower)

Limestone properties: 

- CaCO3 content 

- Reactivity 

- Particle size distribution 

% 

Microns 

Min. 85 

Must comply with vendor 

specification. 

96% < 75 microns 

(To be verified with vendor) 

Gypsum by-product: 

- Application 

- Sulfate / Sulfite ratio 

- Residual moisture 

- 

- 

% 

Disposal 

99 / 1 (Full oxidation) 

15 

Chloride concentration in the slurry ppm 5,500 

Waste water requirements - None. 

3.2 Process description 

The fumes from the potrooms are extracted from the stack of the existing dry gas cleaning systems 

(GTCs). Each stack will be provided with an adaptor and a valve that connects to the collector duct 

for the FGD system. This design allows for the GTCs to continue operation as it is today. The goal is 

that the GTCs do not “see” the additional FGD system. To achieve this, pressure control is applied in 

the collector duct whereby the pressure at the GTCs is maintained constant by a dedicated fan in the 

collector duct. 

The collector ducts go over the potrooms and come together at the central FGD system. In each 

collector duct a damper is added in order to isolate an individual duct. 

The combined fumes are blown into the scrubbing tower. The tower is an open spray design and 

has two spray layers installed. Each layer has a dedicated recycle pump. Because there is a second 

scrubbing tower in standby there is no need to have additional spray layers installed. 

Above the spray layers are two chevron type horizontal mist eliminators. Below the lower mist 

eliminator is the main wash system and between the two mist eliminators is a second wash system. 

There is no need for a third wash system at the top of the stack as this can be washed manually once 

a year. 

The two scrubbing towers vent to a combined stack that emits cleaned gases at a level 

approximately 150 feet above the ground. 
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Two slurry pumps recycle the slurry through the spray levels with the appropriate nozzles. These 

can be either hollow cone or full cone nozzles. The slurry is semi-atomized into a spray of droplets 

that mix with the incoming fumes. 

The bottom of the scrubbing tower fulfills several functions. It has to provide enough liquid head for 

the pumps, it provides for enough retention time for the gypsum to grow into a desirable particle size 

distribution so that is can be dewatered properly, it is used for pH control, and it provides for the 

means to oxidize all the sulphite into sulphate. 

The fumes from the potroom contain close to 20 volume percent of oxygen. Experience with similar 

scrubbing systems of this type shows that 20 volume percent of oxygen is enough to provide full 

oxidation of sulphite into sulphate. However, for safety reasons (one wants to have the slurry fully 

oxidized at all times), a small amount of compressed air is introduced by a small blower. 

A bleed system withdraws slurry from the scrubbing tower. A loop is used to measure the pH while 

the rest is fed to a hydroclone battery. This is the first stage of solids dewatering. The overflow of 

the hydroclones is returned to the scrubbing tower while the underflow is collected and fed to a 

vacuum filter. The system is engineered such that the underflow can be fed directly onto the filter. 

The thickened slurry is dewatered on the vacuum filter to about 85 percent dry solids. The filtrate 

and wash/rinse water is collected and returned to the scrubbing tower. The gypsum is left with 15 

percent moisture which prevents the need for a liquid purge stream otherwise needed to purge 

impurities from the process. The gypsum is moist enough to be stored in semi open warehouse and 

can be loaded into dump trucks and taken to a third party. 

Limestone is delivered in powder form and added to the process water and fed from the slurry tank 

to the scrubbing tower via a pH control system. 

3.3 Mass balance of an FGD system treating the fumes from the potrooms 

Limestone slurry

storage tank

Limestone

silo

Make-up

water

Wash & rinse water

Filtrate tank Gypsum product

Vacuum

Belt filter

Hydroclones

Belt filter 

feed tank

Scrubber

Oxidation

air

Gas outlet
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GAS (lb/hr) Fumes from 

one potroom

Fumes from 6 

potrooms Oxidation air Clean gases

N2 1,025,647 6,153,884 4,514 6,158,398 

O2 285,454 1,712,725 1,368 1,713,645 

CO2 413 2,479 3 3,751 

H2O 25,375 152,251 82 324,134 

H20 (l) - - - 653 

SO2 316 1,893 - 95 

SO3 - - - - 

HCl - - - - 

HF 5 32 - 1 

Particulate 5 32 - 11 

Mass flow (lb/hr) 8,023,295 1,337,216 5,967 8,200,687 

Volume flow (ACFM) 2,214,685 369,114 1,365 1,984,246 

Volume flow (SCFM) 1,814,887 302,481 1,343 1,877,773 

Temperature (°F) 189 189 77 98 

Pressure (Inch WG) 407.7 407.7 405.3 405.3 

LIQUID / 

SOLIDS (lb/hr)

Absorber 

recycle Absorber bleed pH loop Hydroclone 

overflow

Hydroclone 

underflow

Liquid 30,849,560 78,847 25,708 46,671 6,467 

Solids 5,444,040 13,914 4,537 4,086 5,291 

Total 36,293,600 92,761 30,245 50,757 11,759 

Solids concentration 15 15 15 8 45

Density (SG) 1.10 1.10 1.10 1.05 1.34

Flow (GPM) 169 66,050 55 96 18 

LIQUID / 

SOLIDS (lb/hr)

Vacuum filter 

feed

Filter wash 

water Rinse water Filtrate Gypsum

Liquid 6,467 - 10,530 16,068 929 

Solids 5,291 - - 26 5,265 

Total 11,759 - 10,530 16,095 6,194 

Solids concentration 45 - - 0.2 85 

Density (SG) 1.00 1.34 1.00 1.01 1.50 

Flow (GPM) - 18 21 32 -

LIQUID / 

SOLIDS (lb/hr) Limestone Process water

Limestone 

slurry to 

absorber

Liquid - 9,757 9,757 

Solids 3,252 - 3,252 

Total 3,252 9,757 13,009 

Solids concentration 100 - 25 

Density (SG) 1.00 2.80 1.19 

Flow (GPM) - - - 

LIQUID / 

SOLIDS (lb/hr)

Process water 

intake

Water to 

absorber

Water to 

limestone 

preparation

Water to 

gypsum 

dewatering

Water for 

oxidation air 

cooling

Liquid 174,362 152,973 9,757 10,530 1,102 

Solids - - - - -

Total 174,362 152,973 9,757 10,530 1,102 

Solids concentration - - - - -

Density (SG) 1.00 1.00 1.00 1.00 1.00 

Flow (GPM) 306 348 19 21 2 
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3.4 Consumables 

The following list presents the main consumables for the FGD system treating the fumes from the 

potrooms. 

Table 5: Consumables 

Consumable Unit Value 

Process water US Gallons per day 500,000 

Limestone Short tons per day 39 

Compressed air SCFM 150 

Electric power kWh/h 7,400 

3.5 Scope of work 

The following is the scope of work used to develop the cost estimates. The overall basis is a lump 

sum contract with a single vendor/contractor. 

GTC connections

All GTC stacks will be equipped with an adaptor that connect them to common scrubber ducts. The 

adaptors fit on the stacks and a valve is included. 

Collector ducts

Each GTC will be connected to a collector duct and fan system. There are six collector ducts and fan 

systems, including isolation valves. The work includes structural steel work needed to position the 

collector ducts over the potrooms and to the central FGD system. 

Scrubbing tower

Two scrubbing towers are included and they both are identical in size and have the same equipment 

and controls so that they can be operated independently from each other. 

On the bottom, two 48-inch diameter pipes are connected to the tower and the suction of the recycle 

pumps. Each suction pipe has included a butterfly type valve to isolate a pump. Each recycle pump 

operates at 33,000 GPM. The discharge is also 48 inches in diameter and goes up the spray levels. 

Inside the scrubbing tower two spray levels are installed that form a network of smaller diameter 

pipes in order to provide equal distribution of the slurry over the cross section of the tower. 

A common water supply system (tank and pumps) serves both scrubbing towers. It will connect to 

the three wash levels above the mist eliminators. 

A common air compressor is included for the supply of oxidation air. To prevent clogging of the line 

where air is injected, water is injected to saturate the air before it hits the slurry in the scrubbing 

tower. 
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Primary dewatering

A first dewatering step is needed to create the right slurry density for final dewatering. A set of 

hydroclones is included to thicken the slurry from 15 percent solids to about 45 percent. The 

hydroclone set has included a chute to intercept the thickened slurry in case of a line blockage. In 

that case all slurry is returned. 

Secondary dewatering

A vacuum belt filter is included for the dewatering of the gypsum slurry. This has included a vacuum 

system, wash & rinse system and discharge chute. In order to provide limited redundancy, two 75 

percent capacity filters are included. 

A filtrate collection system is incorporated to return any liquids to the scrubbing tower. 

The vacuum filters are elevated in a building and the lower section has a dump & storage area for the 

gypsum. A front loader picks up the gypsum and dumps it into a dump truck for disposal. 

Limestone system

The scope of work also includes an integrated silo and slurry preparation tank. Trucks are equipped 

with unloading equipment to deliver the limestone powder into the tank. The tank is provided with 

an agitator and pump set. The pumps are connected to a loop that passes both scrubbing towers. 

Slurry is drawn from the loop based on pH control. Dosing valves are included. 

General systems and facilities

To prevent any uncontrolled releases into the environment, a slurry collection system is included in 

and around the central system to collect spills and overflows. A sump with a submerged pump is 

included and all slurry is transferred to the operating scrubbing tower. 

The vendor will provide all automation and control systems to minimize manual intervention 

required from operating personnel. 

Chemical sampling and analysis is added to the current work load of the laboratory staff. Some new 

equipment like slurry analysers will be provided. 
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4. FGD System for the Baking Furnace 

4.1 Design basis 

The following table presents the design basis for the FGD system serving the baking furnace. 

Table 6: Design basis for the baking furnace FGD system – Intalco Works 

Design parameter Unit Value 

Number of fires in service - All 

Total flow of fumes in the existing stack ACFM 216,000 

Nominal fume temperature °F 205 

Composition of the baking furnace fumes at the inlet of the FGD system 

Sulphur dioxide (SO2) ppmv 25 (5.33 grams/sec) 

Hydrogen fluoride (HFg) mg/Nm3 5 

Water vapour (H2O) vol% 20.7 

Particulates mg/Nm3 <5 (0.35 grams/sec) 

In addition, the following system requirements are applied in the design of the system. 

Table 7: Design requirements for the baking furnace FGD system 

Aspect Unit Requirement 

Desulphurization efficiency % Min. 95 

Removal efficiency of particulates and 

fluorides 

- No increment 

Residual droplets mg/Nm3 Max. 100 

Spare scrubbing capacity % 100 

(1 full scrubbing tower standby/no spare spray layers inside 

one scrubbing tower)

Limestone properties: 

- CaCO3 content 

- Reactivity 

- Particle size distribution 

% 

Microns 

Min. 85 

Must comply with vendor 

specification. 

96% < 75 microns 

(To be verified with vendor) 
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Gypsum by-product: 

- Application 

- Sulfate / Sulfite ratio 

- Residual moisture 

- 

- 

% 

Disposal 

99 / 1 (Full oxidation) 

15 

Chloride concentration in the slurry ppm 7,500 

Waste water requirements - None. 

4.2 Process description 

The fumes from the ring duct are passed on to the evaporative cooling tower to cool the fumes and 

to precipitate some of the tars. The fumes are led into the dry gas cleaning system in which alumina 

is injected for particulate, tar, and fluoride removal. The fumes pass the bag filters and enter the 

plenum outlet. 

The combined fumes are blown into the scrubbing tower. The tower is an open spray design and 

has two spray layers. Each layer has a dedicated recycle pump. Because there is a second scrubbing 

tower in standby there is no need to have additional spray layers. 

Above the spray layers are two chevron type horizontal mist eliminators. Below the lower mist 

eliminator is the main wash system and between the two mist eliminators is a second wash system. 

There is no need for a third wash system at the top of the stack as this can be washed manually once 

a year. 

The scrubbing tower has an integrated stack that emits the clean gases at a level approximately 150 

feet above the ground. 

Two slurry pumps recycle the slurry through the spray levels with the appropriate nozzles. These 

can be either hollow cone or full cone nozzles. The slurry is semi-atomized into a spray of droplets 

and washes the incoming fumes. 

The bottom of the scrubbing tower fulfills several functions. It has to provide enough liquid head for 

the pumps, it provides for enough retention time for the gypsum to grow into a desirable particle size 

distribution so that is can be dewatered properly, it is used for pH control, and it provides for the 

means to oxidize all the sulphite into sulphate. All this is incorporated within the design. 

Air is injected under the liquid level of the scrubber tower bottom to provide for the required 

oxidation sulphites into sulphates. A small blower is used to inject the air. 

A bleed system withdraws slurry from the scrubbing tower. A loop is used to measure the pH while 

the rest is fed to a hydroclone battery. This is the first stage of solids dewatering. The overflow of 

the hydroclones is returned to the scrubbing tower while the underflow is collected and fed to a 

vacuum filter. The system is engineered such that the underflow can be fed directly onto the filter. 

The thickened slurry is dewatered on the vacuum filter to about 85 percent dry solids. The filtrate 

and wash/rinse water is collected and returned to the scrubbing tower. The gypsum is left with 15 

percent moisture which will prevents the need for a liquid purge stream otherwise needed to purge 
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impurities from the process. The gypsum is moist enough to be stored in semi open warehouse and 

can be loaded into dump trucks and taken to a third party. 

Limestone is delivered in powder form and added to the process water and fed from the slurry tank 

to the scrubbing tower via a pH control system. 

4.3 Mass balance for an FGD system to treat the fumes from the baking furnace 

GAS (lb/hr)

Fumes from dry 

gas cleaning 

system

Oxidation air Clean gases

N2 516,752 224 516,977 

O2 24,683 68 24,741 

CO2 88,656 0 88,687 

H2O 99,881 4 111,652 

H20 (l) - - 61 

SO2 42 - 2 

SO3 - - - 

HCl - - - 

HF 3 - 0 

Particulate 3 - 1 

Mass flow (lb/hr) 297 730,020 742,121 

Volume flow (ACFM) 68 218,111 202,525 

Volume flow (SCFM) 67 172,510 176,787 

Temperature (°F) 77 212 145 

Pressure (Inch WG) 405.3 407.7 405.3 

LIQUID / 

SOLIDS (lb/hr)

Absorber 

recycle Absorber bleed pH loop Hydroclone 

overflow

Hydroclone 

underflow

Liquid 1,616,844 26,676 25,427 1,097 152 

Solids 285,325 4,707 4,487 96 124 

Total 1,902,170 31,383 29,914 1,193 276 

Solids concentration 15 15 15 8.05 45

Density (SG) 1.09 1.09 1.09 1.02 1.31

Flow (GPM) 58 3,500 55 2.3 0.4 

Limestone slurry

storage tank

Limestone

silo

Make-up

water

Wash & rinse water

Filtrate tank Gypsum product

Vacuum

Belt filter

Hydroclones

Belt filter 

feed tank

Scrubber

Oxidation

air

Gas outlet
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LIQUID / 

SOLIDS (lb/hr)

Vacuum filter 

feed

Filter wash 

water Rinse water Filtrate Gypsum

Liquid 152 - 247 378 22 

Solids 124 - - 1 124 

Total 276 - 247 378 146 

Solids concentration 45 - - 0 85 

Density (SG) 1.00 1.33 1.00 1.00 1.50 

Flow (GPM) - 0.4 0.5 0.8 - 

LIQUID / 

SOLIDS (lb/hr) Limestone Process water

Limestone 

slurry to 

absorber

Liquid - 235 235 

Solids 78 - 78 

Total 78 235 314 

Solids concentration 100 - 25 

Density (SG) 1.19 2.80 1.00 

Flow (GPM) 0.5 - 0.5 

LIQUID / 

SOLIDS (lb/hr)

Process water 

intake

Water to 

absorber

Water to 

limestone 

preparation

Water to 

gypsum 

dewatering

Water for 

oxidation air 

cooling

Liquid 11,865 10,279 235 247 1,102 

Solids - - - - -

Total 11,865 10,279 235 247 1,102 

Solids concentration - - - - -

Density (SG) 1.00 1.00 1.00 1.00 1.00 

Flow (GPM) 21 24 0.5 0.5 2.2 

4.4 Consumables 

The following list presents the main consumables for the control system. 

Table 8: Baking furnace FGD consumables 

Consumable Unit Value 

Process water US Gallons per day 35,000 

Limestone Short tons per day 1.0 

Compressed air SCFM 50 

Electric power kWh/h 750 

4.5 Scope of work 

The following is the scope of work used to develop the cost estimates. The overall basis is a lump 

sum contract with a single vendor/contractor. 
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GTC connection

New fans will be installed to replace the existing fans downstream of the dry gas cleaning system. 

The fans are provided with an inlet manifold that connects to the scrubbing towers. Isolation 

dampers are included to separate one scrubbing tower from operation. 

Scrubbing tower

Two scrubbing towers are included and they both are identical in size and have the same equipment 

and controls so that they can operate independently from each other. 

The bottom two 4 inch diameter pipes are connected to the tower and the suction of the recycle 

pumps. Each suction pipe has included a butterfly type valve to isolate the pump. Each recycle 

pump operates at 1,750 GPM. The discharge is also 4 inches in diameter and goes to the spray 

levels. Inside the scrubbing tower two spray levels are installed and form a network of smaller 

diameter pipes in order to provide equal distribution of the slurry over the cross section of the tower. 

A common water supply system (tank and pumps) serves both scrubbing towers. It will connect to 

the three wash levels around the mist eliminators. 

A common air compressor is included for the supply of oxidation air. To prevent clogging of the line 

where air is injected, water is injected to saturate the air before it hits the slurry in the scrubbing 

tower. 

Primary dewatering

A first dewatering step is needed to create the right slurry density for final dewatering. A set of 

hydroclones is included to thicken the slurry from 15 percent solids to about 45 percent. The 

hydroclone set has included a chute to intercept the thickened slurry in case nothing can go to the 

filter. In that case all slurry is returned. 

Secondary dewatering

A vacuum belt filter is included for the dewatering of the gypsum slurry. This has included a vacuum 

system, wash & rinse system and discharge chute. In order to provide limited redundancy two 75 

percent capacity filters are included. 

A filtrate collection system is incorporated to return any liquids to the scrubbing tower. 

The vacuum filters are elevated in a building and the lower section has a dump & storage area for the 

gypsum. A front loader picks up the gypsum and dumps it into a dump truck for disposal. 

Limestone system

The scope of work also includes an integrated silo and slurry preparation tank. Trucks are equipped 

with unloading equipment to deliver the limestone powder into the tank. The tank is provided with 

an agitator and pump set. The pumps are connected to a loop that passes both scrubbing towers. 

Slurry is drawn from the loop based on pH control. Dosing valves are included. 
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General systems and facilities 

To prevent any uncontrolled releases into the environment, a slurry collection system is included in 

and around the central system to collect spills and overflows. A sump with a submerged pump is 

included and all slurry is transferred to the operating scrubbing tower. 

The vendor will provide all automation and control systems to minimize manual intervention 

required from operating personnel. 

Chemical sampling and analysis is added to the current work load of the laboratory staff. Some new 

equipment like slurry analysers will be provided. 
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5. Capital cost estimates 

In this section are provided all capital cost estimates for both the potroom FGD system and the 

baking furnace FGD system. 

All equipment cost estimates are based on cost proposals provided by Alstom Power and Babcock 

Power for Alcoa’s smelter in Alcoa, TN and a pre-feasibility study prepared by Hatch for the Alcoa 

TN smelter, entitled “SO2 Scrubber for Alcoa Tennessee” (June 7, 2007 (Hatch report number 

PRH322820.0001). 

5.1 Methodology 

For this high level study, costs have been scaled based on specific design and operational aspects of 

FGD systems. The key three scaling parameters are the volume of gases going through, the amount of 

limestone consumed and the amount of gypsum by-product produced. These three parameters help 

scale certain parts of the FGD system scale properly; however, to apply such method a break down is 

required for the cost provided in the study for Alcoa Tennessee works. This was not presented in the 

previous study and as such it has been included here. 

Based on Hatch’ experience with cost analysis of FGD systems the following break down is derived 

and applied in this study: 

Table 9: Break down of FGD sub system costs 

Sub system Fraction of cost of the total 

Reagent feed system 10% of TPC 

SO2 removal system 35% of TPC 

Flue gas system 30% of TPC 

By-product handling 10% of TPC 

General support equipment 15% of TPC 

TOTAL PROCESS CAPITAL (TPC) 100% 
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Table 10: Cost break down of the Alcoa Tennessee works FGD system. 

All values in million USD

Equipment Installation Subtotal

Reagent feed system $6.50 $6.50 $13.00

SO2 removal system $22.75 $22.75 $45.50

Flue gas system $19.50 $19.50 $39.00

Byproduct handling $6.50 $6.50 $13.00

General support equipment $9.75 $9.75 $19.50

TOTAL PROCESS CAPITAL $65.00 $65.00 $130.00

TENNESSEE POTLINE FGD

This table is used as a basis for the tables that follow and represent the results for the Intalco smelter. 

Next step in the methodology is to convert the sub system costs from one case to another. For this 

the general formula of cost scaling is applied: 

n

Q

Q P P 













 = ×

1

2

2 1

From the Hatch database of cost information related to large FGD systems is further derived: 

Table 11: Exponent n for scaled cost estimation. 

Sub system Exponent n 

Reagent feed system 0.33 

SO2 removal system 0.50 

Flue gas system 0.50 

By-product handling 0.40 

General support equipment 0.15 

These exponents apply to large scale FGD units. For the baking furnace, which is much smaller, in 

the report is applied an exponent of 0.8 for all sub systems. This is consistent with earlier work 

prepared by the Alcoa team. 

In order to scale costs between the different cases the following scaling factors have been applied: 
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Table 12: Scaling parameters. 

Scaling value 

Parameter 

Tennessee 

(Q1) 

Intalco Potline 

(Q2) 

Intalco Baking Furnace 

(Q2) 

Clean flue gas flow (ACFM) 1,582,432 1,948,246 202,525 

Limestone consumption (tpa) 10,407 12,921 315 

Gypsum production (tpa) 19,272 24,607 578 

Example: 

9.59

10,407

12,921 8.93

0.33

2  = 

 



 P = x 

This example shows that for Intalco the estimate costs for the reagent (limestone) feed system is 9.59 

million USD. 

5.2 Cost estimate for the potline FGD system 

The following table presents the results from the cost estimation for the FGD system, servicing the 

potline ventilation fumes at Intalco. 

Table 13: Cost estimate for the Intalco Works potline FGD system 

All values in million USD

Equipment Installation Subtotal

Reagent feed system $6.98 $6.98 $13.96

SO2 removal system $25.24 $25.24 $50.49

Flue gas system $21.64 $21.64 $43.27

Byproduct handling $7.17 $7.17 $14.33

General support equipment $10.11 $10.11 $20.23

TOTAL PROCESS CAPITAL $71.14 $71.14 $142.28

POTLINE FGD

5.3 Cost estimate for the baking furnace FGD system 

The following table presents the results from the cost estimation for the FGD system, servicing the 

potline ventilation fumes at Intalco. 
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Table 14: Cost estimate for the Intalco Works baking furnace FGD system. 

All values in million USD

Equipment Installation Subtotal

Reagent feed system $0.36 $0.36 $0.72

SO2 removal system $4.13 $4.13 $8.25

Flue gas system $3.54 $3.54 $7.07

Byproduct handling $0.36 $0.36 $0.71

General support equipment $0.50 $0.50 $1.01

TOTAL PROCESS CAPITAL $8.88 $8.88 $17.76

BAKING FURNACE FGD

S. Broek 
Sheridan Science and Technology Park, 2800 Speakman Drive 

Mississauga, Ontario, Canada L5K 2R7 

Tel 905 855 7600  Fax 905 855 8270 
39156 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

requirements, Sulfur oxides, Volatile 

organic compounds.

Dated: June 15, 2005. 

Stephen L. Johnson, 

Administrator.

■ For the reasons set forth in the 

preamble, part 51 of chapter I of title 40 

of the Code of Federal Regulations is 

amended as follows:

PART 51—REQUIREMENTS FOR 

PREPARATION, ADOPTION, AND 

SUBMITTAL OF IMPLEMENTATION 

PLANS

■ 1. The authority citation for part 51 

continues to read as follows:

Authority: 23 U.S.C. 101; 42 U.S.C. 7410–

7671q.

■ 2. Section 51.302 is amended by 

revising paragraph (c)(4)(iii) to read as 

follows:

§ 51.302 Implementation control strategies 

for reasonably attributable visibility 

impairment.

* * * * *

(c) * * * 

(4) * * * 

(iii) BART must be determined for 

fossil-fuel fired generating plants having 

a total generating capacity in excess of 

750 megawatts pursuant to ‘‘Guidelines 

for Determining Best Available Retrofit 

Technology for Coal-fired Power Plants 

and Other Existing Stationary Facilities’’

(1980), which is incorporated by 

reference, exclusive of appendix E to the 

Guidelines, except that options more 

stringent than NSPS must be 

considered. Establishing a BART 

emission limitation equivalent to the 

NSPS level of control is not a sufficient 

basis to avoid the analysis of control 

options required by the guidelines. This 

document is EPA publication No. 450/

3–80–009b and has been approved for 

incorporation by reference by the 

Director of the Federal Register in 

accordance with 5 U.S.C. 552(a) and 1 

CFR part 51. It is for sale from the U.S. 

Department of Commerce, National 

Technical Information Service, 5285 

Port Royal Road, Springfield, Virginia 

22161. It is also available for inspection 

from the National Archives and Records 

Administration (NARA). For 

information on the availability of this 

material at NARA, call 202–741–6030, 

or go to: http://www.archives.gov/

federal_register/index.html.

* * * * *

■ 3. Section 51.308 is amended by 

revising paragraph (b), removing and 

reserving paragraph (c), revising 

paragraphs (e)(1)(ii), (e)(3), and (e)(4), 

and adding paragaphs (e)(5) and (6) to 

read as follows:

§ 51.308 Regional haze program 

requirements.

* * * * *

(b) When are the first implementation 

plans due under the regional haze 

program? Except as provided in 

§ 51.309(c), each State identified in 

§ 51.300(b)(3) must submit, for the 

entire State, an implementation plan for 

regional haze meeting the requirements 

of paragraphs (d) and (e) of this section 

no later than December 17, 2007. 

(c) [Reserved]

* * * * *

(e) * * * 

(1) * * * 

(ii) A determination of BART for each 

BART-eligible source in the State that 

emits any air pollutant which may 

reasonably be anticipated to cause or 

contribute to any impairment of 

visibility in any mandatory Class I 

Federal area. All such sources are 

subject to BART. 

(A) The determination of BART must 

be based on an analysis of the best 

system of continuous emission control 

technology available and associated 

emission reductions achievable for each 

BART-eligible source that is subject to 

BART within the State. In this analysis, 

the State must take into consideration 

the technology available, the costs of 

compliance, the energy and nonair 

quality environmental impacts of 

compliance, any pollution control 

equipment in use at the source, the 

remaining useful life of the source, and 

the degree of improvement in visibility 

which may reasonably be anticipated to 

result from the use of such technology. 

(B) The determination of BART for 

fossil-fuel fired power plants having a 

total generating capacity greater than 

750 megawatts must be made pursuant 

to the guidelines in appendix Y of this 

part (Guidelines for BART 

Determinations Under the Regional 

Haze Rule).

(C) Exception. A State is not required 

to make a determination of BART for 

SO2 or for NOX if a BART-eligible 

source has the potential to emit less 

than 40 tons per year of such 

pollutant(s), or for PM10 if a BARTeligible source emits less than 15 tons 

per year of such pollutant.

* * * * *

(3) A State which opts under 40 CFR 

51.308(e)(2) to implement an emissions 

trading program or other alternative 

measure rather than to require sources 

subject to BART to install, operate, and 

maintain BART may satisfy the final 

step of the demonstration required by 

that section as follows: If the 

distribution of emissions is not 

substantially different than under 

BART, and the alternative measure 

results in greater emission reductions, 

then the alternative measure may be 

deemed to achieve greater reasonable 

progress. If the distribution of emissions 

is significantly different, the State must 

conduct dispersion modeling to 

determine differences in visibility 

between BART and the trading program 

for each impacted Class I area, for the 

worst and best 20 percent of days. The 

modeling would demonstrate ‘‘greater 

reasonable progress’’ if both of the 

following two criteria are met: 

(i) Visibility does not decline in any 

Class I area, and 

(ii) There is an overall improvement 

in visibility, determined by comparing 

the average differences between BART 

and the alternative over all affected 

Class I areas. 

(4) A State that opts to participate in 

the Clean Air Interstate Rule cap-andtrade and trade program under part 96 

AAA–EEE need not require affected 

BART-eligible EGU’s to install, operate, 

and maintain BART. A State that 

chooses this option may also include 

provisions for a geographic 

enhancement to the program to address 

the requirement under § 51.302(c) 

related to BART for reasonably 

attributable impairment from the 

pollutants covered by the CAIR cap-andtrade program. 

(5) After a State has met the 

requirements for BART or implemented 

emissions trading program or other 

alternative measure that achieves more 

reasonable progress than the installation 

and operation of BART, BART-eligible 

sources will be subject to the 

requirements of paragraph (d) of this 

section in the same manner as other 

sources. 

(6) Any BART-eligible facility subject 

to the requirement under paragraph (e) 

of this section to install, operate, and 

maintain BART may apply to the 

Administrator for an exemption from 

that requirement. An application for an 

exemption will be subject to the 

requirements of § 51.303(a)(2)–(h).

* * * * *

■ 4. Appendix Y to Part 51 is added to 

read as follows:

Appendix Y to Part 51—Guidelines for 

BART Determinations Under the 

Regional Haze Rule 

Table of Contents 

I. Introduction and Overview 

A. What is the purpose of the guidelines? 

B. What does the CAA require generally for 

improving visibility? 

C. What is the BART requirement in the 

CAA? 

D. What types of visibility problems does 

EPA address in its regulations? 

Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39157

E. What are the BART requirements in 

EPA’s regional haze regulations? 

F. What is included in the guidelines? 

G. Who is the target audience for the 

guidelines? 

H. Do EPA regulations require the use of 

these guidelines? 

II. How to Identify BART-eligible Sources 

A. What are the steps in identifying BARTeligible sources? 

1. Step 1: Identify emission units in the 

BART categories 

2. Step 2: Identify the start-up dates of the 

emission units 

3. Step 3: Compare the potential emissions 

to the 250 ton/yr cutoff 

4. Final step: Identify the emission units 

and pollutants that constitute the BARTeligible source. 

III. How to Identify Sources ‘‘Subject to 

BART’’

IV. The BART Determination: Analysis of 

BART Options 

A. What factors must I address in the 

BART Analysis? 

B. What is the scope of the BART review? 

C. How does a BART review relate to 

maximum achievable control technology 

(MACT) standards under CAA section 

112? 

D. What are the five basic steps of a caseby-case BART analysis? 

1. Step 1: How do I identify all available 

retrofit emission control techniques? 

2. Step 2: How do I determine whether the 

options identified in Step 1 are 

technically feasible? 

3. Step 3: How do I evaluate technically 

feasible alternatives? 

4. Step 4: For a BART review, what 

impacts am I expected to calculate and 

report? What methods does EPA 

recommend for the impacts analyses? 

a. Impact analysis part 1: how do I estimate 

the costs of control? 

b. What do we mean by cost effectiveness? 

c. How do I calculate average cost 

effectiveness? 

d. How do I calculate baseline emissions? 

e. How do I calculate incremental cost 

effectiveness?

f. What other information should I provide 

in the cost impacts analysis? 

g. What other things are important to 

consider in the cost impacts analysis? 

h. Impact analysis part 2: How should I 

analyze and report energy impacts? 

i. Impact analysis part 3: How do I analyze 

‘‘non-air quality environmental 

impacts?’’

j. Impact analysis part 4: What are 

examples of non-air quality 

environmental impacts? 

k. How do I take into account a project’s 

‘‘remaining useful life’’ in calculating 

control costs? 

5. Step 5: How should I determine 

visibility impacts in the BART 

determination? 

E. How do I select the ‘‘best’’ alternative, 

using the results of Steps 1 through 5? 

1. Summary of the impacts analysis 

2. Selecting a ‘‘best’’ alternative 

3. In selecting a ‘‘best’’ alternative, should 

I consider the affordability of controls? 

4. SO2 limits for utility boilers 

5. NOX limits for utility boilers 

V. Enforceable Limits/Compliance Date 

I. Introduction and Overview 

A. What is the purpose of the guidelines? 

The Clean Air Act (CAA), in sections 169A 

and 169B, contains requirements for the 

protection of visibility in 156 scenic areas 

across the United States. To meet the CAA’s 

requirements, we published regulations to 

protect against a particular type of visibility 

impairment known as ‘‘regional haze.’’ The 

regional haze rule is found in this part at 40 

CFR 51.300 through 51.309. These 

regulations require, in 40 CFR 51.308(e), that 

certain types of existing stationary sources of 

air pollutants install best available retrofit 

technology (BART). The guidelines are 

designed to help States and others (1) 

identify those sources that must comply with 

the BART requirement, and (2) determine the 

level of control technology that represents 

BART for each source. 

B. What does the CAA require generally for 

improving visibility? 

Section 169A of the CAA, added to the 

CAA by the 1977 amendments, requires 

States to protect and improve visibility in 

certain scenic areas of national importance. 

The scenic areas protected by section 169A 

are ‘‘the mandatory Class I Federal Areas 

* * * where visibility is an important 

value.’’ In these guidelines, we refer to these 

as ‘‘Class I areas.’’ There are 156 Class I areas, 

including 47 national parks (under the 

jurisdiction of the Department of Interior—

National Park Service), 108 wilderness areas 

(under the jurisdiction of the Department of 

the Interior—Fish and Wildlife Service or the 

Department of Agriculture—U.S. Forest 

Service), and one International Park (under 

the jurisdiction of the Roosevelt-Campobello 

International Commission). The Federal 

Agency with jurisdiction over a particular 

Class I area is referred to in the CAA as the 

Federal Land Manager. A complete list of the 

Class I areas is contained in 40 CFR 81.401 

through 81.437, and you can find a map of 

the Class I areas at the following Internet site: 

http://www.epa.gov/ttn/oarpg/t1/fr_notices/

classimp.gif.

The CAA establishes a national goal of 

eliminating man-made visibility impairment 

from all Class I areas. As part of the plan for 

achieving this goal, the visibility protection 

provisions in the CAA mandate that EPA 

issue regulations requiring that States adopt 

measures in their State implementation plans 

(SIPs), including long-term strategies, to 

provide for reasonable progress towards this 

national goal. The CAA also requires States 

to coordinate with the Federal Land 

Managers as they develop their strategies for 

addressing visibility. 

C. What is the BART requirement in the 

CAA? 

1. Under section 169A(b)(2)(A) of the CAA, 

States must require certain existing stationary 

sources to install BART. The BART provision 

applies to ‘‘major stationary sources’’ from 26 

identified source categories which have the 

potential to emit 250 tons per year or more 

of any air pollutant. The CAA requires only 

sources which were put in place during a 

specific 15-year time interval to be subject to 

BART. The BART provision applies to 

sources that existed as of the date of the 1977 

CAA amendments (that is, August 7, 1977) 

but which had not been in operation for more 

than 15 years (that is, not in operation as of 

August 7, 1962). 

2. The CAA requires BART review when 

any source meeting the above description 

‘‘emits any air pollutant which may 

reasonably be anticipated to cause or 

contribute to any impairment of visibility’’ in 

any Class I area. In identifying a level of 

control as BART, States are required by 

section 169A(g) of the CAA to consider: 

(a) The costs of compliance, 

(b) The energy and non-air quality 

environmental impacts of compliance, 

(c) Any existing pollution control 

technology in use at the source, 

(d) The remaining useful life of the source, 

and 

(e) The degree of visibility improvement 

which may reasonably be anticipated from 

the use of BART. 

3. The CAA further requires States to make 

BART emission limitations part of their SIPs. 

As with any SIP revision, States must 

provide an opportunity for public comment 

on the BART determinations, and EPA’s 

action on any SIP revision will be subject to 

judicial review.

D. What types of visibility problems does EPA 

address in its regulations? 

1. We addressed the problem of visibility 

in two phases. In 1980, we published 

regulations addressing what we termed 

‘‘reasonably attributable’’ visibility 

impairment. Reasonably attributable 

visibility impairment is the result of 

emissions from one or a few sources that are 

generally located in close proximity to a 

specific Class I area. The regulations 

addressing reasonably attributable visibility 

impairment are published in 40 CFR 51.300 

through 51.307. 

2. On July 1, 1999, we amended these 

regulations to address the second, more 

common, type of visibility impairment 

known as ‘‘regional haze.’’ Regional haze is 

the result of the collective contribution of 

many sources over a broad region. The 

regional haze rule slightly modified 40 CFR 

51.300 through 51.307, including the 

addition of a few definitions in § 51.301, and 

added new §§ 51.308 and 51.309. 

E. What are the BART requirements in EPA’s 

regional haze regulations? 

1. In the July 1, 1999 rulemaking, we added 

a BART requirement for regional haze. We 

amended the BART requirements in 2005. 

You will find the BART requirements in 40 

CFR 51.308(e). Definitions of terms used in 

40 CFR 51.308(e)(1) are found in 40 CFR 

51.301. 

2. As we discuss in detail in these 

guidelines, the regional haze rule codifies 

and clarifies the BART provisions in the 

CAA. The rule requires that States identify 

and list ‘‘BART-eligible sources,’’ that is, that 

States identify and list those sources that fall 

within the 26 source categories, were put in 

place during the 15-year window of time 

from 1962 to 1977, and have potential 

39158 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

emissions greater than 250 tons per year. 

Once the State has identified the BARTeligible sources, the next step is to identify 

those BART-eligible sources that may ‘‘emit 

any air pollutant which may reasonably be 

anticipated to cause or contribute to any 

impairment of visibility.’’ Under the rule, a 

source which fits this description is ‘‘subject 

to BART.’’ For each source subject to BART, 

40 CFR 51.308(e)(1)(ii)(A) requires that States 

identify the level of control representing 

BART after considering the factors set out in 

CAA section 169A(g), as follows:

—States must identify the best system of 

continuous emission control technology for 

each source subject to BART taking into 

account the technology available, the costs 

of compliance, the energy and non-air 

quality environmental impacts of 

compliance, any pollution control 

equipment in use at the source, the 

remaining useful life of the source, and the 

degree of visibility improvement that may 

be expected from available control 

technology.

3. After a State has identified the level of 

control representing BART (if any), it must 

establish an emission limit representing 

BART and must ensure compliance with that 

requirement no later than 5 years after EPA 

approves the SIP. States may establish 

design, equipment, work practice or other 

operational standards when limitations on 

measurement technologies make emission 

standards infeasible. 

F. What is included in the guidelines? 

1. The guidelines provide a process for 

making BART determinations that States can 

use in implementing the regional haze BART 

requirements on a source-by-source basis, as 

provided in 40 CFR 51.308(e)(1). States must 

follow the guidelines in making BART 

determinations on a source-by-source basis 

for 750 megawatt (MW) power plants but are 

not required to use the process in the 

guidelines when making BART 

determinations for other types of sources. 

2. The BART analysis process, and the 

contents of these guidelines, are as follows: 

(a) Identification of all BART-eligible 

sources. Section II of these guidelines 

outlines a step-by-step process for identifying 

BART-eligible sources. 

(b) Identification of sources subject to 

BART. As noted above, sources ‘‘subject to 

BART’’ are those BART-eligible sources 

which ‘‘emit a pollutant which may 

reasonably be anticipated to cause or 

contribute to any impairment of visibility in 

any Class I area.’’ We discuss considerations 

for identifying sources subject to BART in 

section III of the guidance. 

(c) The BART determination process. For 

each source subject to BART, the next step 

is to conduct an analysis of emissions control 

alternatives. This step includes the 

identification of available, technically 

feasible retrofit technologies, and for each 

technology identified, an analysis of the cost 

of compliance, the energy and non-air quality 

environmental impacts, and the degree of 

visibility improvement in affected Class I 

areas resulting from the use of the control 

technology. As part of the BART analysis, the 

State should also take into account the 

remaining useful life of the source and any 

existing control technology present at the 

source. For each source, the State will 

determine a ‘‘best system of continuous 

emission reduction’’ based upon its 

evaluation of these factors. Procedures for the 

BART determination step are described in 

section IV of these guidelines.

(d) Emissions limits. States must establish 

emission limits, including a deadline for 

compliance, consistent with the BART 

determination process for each source subject 

to BART. Considerations related to these 

limits are discussed in section V of these 

guidelines. 

G. Who is the target audience for the 

guidelines? 

1. The guidelines are written primarily for 

the benefit of State, local and Tribal agencies, 

and describe a process for making the BART 

determinations and establishing the emission 

limitations that must be included in their 

SIPs or Tribal implementation plans (TIPs). 

Throughout the guidelines, which are written 

in a question and answer format, we ask 

questions ‘‘How do I * * *? ’’ and answer 

with phrases ‘‘you should * * *, you must 

*** ’’ The ‘‘you’’ means a State, local or 

Tribal agency conducting the analysis. We 

have used this format to make the guidelines 

simpler to understand, but we recognize that 

States have the authority to require source 

owners to assume part of the analytical 

burden, and that there will be differences in 

how the supporting information is collected 

and documented. We also recognize that data 

collection, analysis, and rule development 

may be performed by Regional Planning 

Organizations, for adoption within each SIP 

or TIP. 

2. The preamble to the 1999 regional haze 

rule discussed at length the issue of Tribal 

implementation of the requirements to 

submit a plan to address visibility. As 

explained there, requirements related to 

visibility are among the programs for which 

Tribes may be determined eligible and 

receive authorization to implement under the 

‘‘Tribal Authority Rule’’ (‘‘TAR’’) (40 CFR 

49.1 through 49.11). Tribes are not subject to 

the deadlines for submitting visibility 

implementation plans and may use a 

modular approach to CAA implementation. 

We believe there are very few BART-eligible 

sources located on Tribal lands. Where such 

sources exist, the affected Tribe may apply 

for delegation of implementation authority 

for this rule, following the process set forth 

in the TAR. 

H. Do EPA regulations require the use of 

these guidelines? 

Section 169A(b) requires us to issue 

guidelines for States to follow in establishing 

BART emission limitations for fossil-fuel 

fired power plants having a capacity in 

excess of 750 megawatts. This document 

fulfills that requirement, which is codified in 

40 CFR 51.308(e)(1)(ii)(B). The guidelines 

establish an approach to implementing the 

requirements of the BART provisions of the 

regional haze rule; we believe that these 

procedures and the discussion of the 

requirements of the regional haze rule and 

the CAA should be useful to the States. For 

sources other than 750 MW power plants, 

however, States retain the discretion to adopt 

approaches that differ from the guidelines. 

II. How to Identify BART-Eligible Sources 

This section provides guidelines on how to 

identify BART-eligible sources. A BARTeligible source is an existing stationary 

source in any of 26 listed categories which 

meets criteria for startup dates and potential 

emissions. 

A. What are the steps in identifying BARTeligible sources? 

Figure 1 shows the steps for identifying 

whether the source is a ‘‘BART-eligible 

source:’’

Step 1: Identify the emission units in the 

BART categories, 

Step 2: Identify the start-up dates of those 

emission units, and 

Step 3: Compare the potential emissions to 

the 250 ton/yr cutoff.

Figure 1. How to determine whether a 

source is BART-eligible: 

Step 1: Identify emission units in the 

BART categories

Does the plant contain emissions units in one 

or more of the 26 source categories? 

➜ No ➜ Stop 

➜ Yes ➜ Proceed to Step 2

Step 2: Identify the start-up dates of these 

emission units

Do any of these emissions units meet the 

following two tests? 

In existence on August 7, 1977 

AND 

Began operation after August 7, 1962 

➜ No ➜ Stop 

➜ Yes ➜ Proceed to Step 3

Step 3: Compare the potential emissions 

from these emission units to the 250 ton/yr 

cutoff

Identify the ‘‘stationary source’’ that 

includes the emission units you 

identified in Step 2. 

Add the current potential emissions from 

all the emission units identified in Steps 

1 and 2 that are included within the 

‘‘stationary source’’ boundary. 

Are the potential emissions from these 

units 250 tons per year or more for any 

visibility-impairing pollutant? 

➜ No ➜ Stop 

➜ Yes ➜ These emissions units 

comprise the ‘‘BART-eligible source.’’

1. Step 1: Identify Emission Units in the 

BART Categories 

1. The BART requirement only applies to 

sources in specific categories listed in the 

CAA. The BART requirement does not apply 

to sources in other source categories, 

regardless of their emissions. The listed 

categories are: 

(1) Fossil-fuel fired steam electric plants of 

more than 250 million British thermal units 

(BTU) per hour heat input, 

(2) Coal cleaning plants (thermal dryers), 

(3) Kraft pulp mills, 

(4) Portland cement plants, 

(5) Primary zinc smelters, 

(6) Iron and steel mill plants, 

(7) Primary aluminum ore reduction 

plants, 

Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39159

(8) Primary copper smelters, 

(9) Municipal incinerators capable of 

charging more than 250 tons of refuse per 

day, 

(10) Hydrofluoric, sulfuric, and nitric acid 

plants, 

(11) Petroleum refineries, 

(12) Lime plants, 

(13) Phosphate rock processing plants, 

(14) Coke oven batteries, 

(15) Sulfur recovery plants, 

(16) Carbon black plants (furnace process), 

(17) Primary lead smelters, 

(18) Fuel conversion plants, 

(19) Sintering plants, 

(20) Secondary metal production facilities, 

(21) Chemical process plants, 

(22) Fossil-fuel boilers of more than 250 

million BTUs per hour heat input, 

(23) Petroleum storage and transfer 

facilities with a capacity exceeding 300,000 

barrels, 

(24) Taconite ore processing facilities, 

(25) Glass fiber processing plants, and 

(26) Charcoal production facilities. 

2. Some plants may have emission units 

from more than one category, and some 

emitting equipment may fit into more than 

one category. Examples of this situation are 

sulfur recovery plants at petroleum 

refineries, coke oven batteries and sintering 

plants at steel mills, and chemical process 

plants at refineries. For Step 1, you identify 

all of the emissions units at the plant that fit 

into one or more of the listed categories. You 

do not identify emission units in other 

categories.

Example: A mine is collocated with an 

electric steam generating plant and a coal 

cleaning plant. You would identify emission 

units associated with the electric steam 

generating plant and the coal cleaning plant, 

because they are listed categories, but not the 

mine, because coal mining is not a listed 

category.

3. The category titles are generally clear in 

describing the types of equipment to be 

listed. Most of the category titles are very 

broad descriptions that encompass all 

emission units associated with a plant site 

(for example, ‘‘petroleum refining’’ and ‘‘kraft 

pulp mills’’). This same list of categories 

appears in the PSD regulations. States and 

source owners need not revisit any 

interpretations of the list made previously for 

purposes of the PSD program. We provide the 

following clarifications for a few of the 

category titles: 

(1) ‘‘Steam electric plants of more than 250 

million BTU/hr heat input.’’ Because the 

category refers to ‘‘plants,’’ we interpret this 

category title to mean that boiler capacities 

should be aggregated to determine whether 

the 250 million BTU/hr threshold is reached. 

This definition includes only those plants 

that generate electricity for sale. Plants that 

cogenerate steam and electricity also fall 

within the definition of ‘‘steam electric 

plants’’. Similarly, combined cycle turbines 

are also considered ‘‘steam electric plants’’

because such facilities incorporate heat 

recovery steam generators. Simple cycle 

turbines, in contrast, are not ‘‘steam electric 

plants’’ because these turbines typically do 

not generate steam.

Example: A stationary source includes a 

steam electric plant with three 100 million 

BTU/hr boilers. Because the aggregate 

capacity exceeds 250 million BTU/hr for the 

‘‘plant,’’ these boilers would be identified in 

Step 2.

(2) ‘‘Fossil-fuel boilers of more than 250 

million BTU/hr heat input.’’ We interpret this 

category title to cover only those boilers that 

are individually greater than 250 million 

BTU/hr. However, an individual boiler 

smaller than 250 million BTU/hr should be 

subject to BART if it is an integral part of a 

process description at a plant that is in a 

different BART category—for example, a 

boiler at a Kraft pulp mill that, in addition 

to providing steam or mechanical power, 

uses the waste liquor from the process as a 

fuel. In general, if the process uses any byproduct of the boiler and the boiler’s function 

is to serve the process, then the boiler is 

integral to the process and should be 

considered to be part of the process 

description. 

Also, you should consider a multi-fuel 

boiler to be a ‘‘fossil-fuel boiler’’ if it burns 

any amount of fossil fuel. You may take 

federally and State enforceable operational 

limits into account in determining whether a 

multi-fuel boiler’s fossil fuel capacity 

exceeds 250 million Btu/hr. 

(3) ‘‘Petroleum storage and transfer 

facilities with a capacity exceeding 300,000 

barrels.’’ The 300,000 barrel cutoff refers to 

total facility-wide tank capacity for tanks that 

were put in place within the 1962–1977 time 

period, and includes gasoline and other 

petroleum-derived liquids. 

(4) ‘‘Phosphate rock processing plants.’’

This category descriptor is broad, and 

includes all types of phosphate rock 

processing facilities, including elemental 

phosphorous plants as well as fertilizer 

production plants. 

(5) ‘‘Charcoal production facilities.’’ We 

interpret this category to include charcoal 

briquet manufacturing and activated carbon 

production. 

(6) ‘‘Chemical process plants.’’ and 

pharmaceutical manufacturing. Consistent 

with past policy, we interpret the category 

‘‘chemical process plants’’ to include those 

facilities within the 2-digit Standard 

Industrial Classification (SIC) code 28. 

Accordingly, we interpret the term ‘‘chemical 

process plants’’ to include pharmaceutical 

manufacturing facilities. 

(7) ‘‘Secondary metal production.’’ We 

interpret this category to include nonferrous 

metal facilities included within SIC code 

3341, and secondary ferrous metal facilities 

that we also consider to be included within 

the category ‘‘iron and steel mill plants.’’

(8) ‘‘Primary aluminum ore reduction.’’ We 

interpret this category to include those 

facilities covered by 40 CFR 60.190, the new 

source performance standard (NSPS) for 

primary aluminum ore reduction plants. This 

definition is also consistent with the 

definition at 40 CFR 63.840. 

2. Step 2: Identify the Start-Up Dates of the 

Emission Units 

1. Emissions units listed under Step 1 are 

BART-eligible only if they were ‘‘in 

existence’’ on August 7, 1977 but were not 

‘‘in operation’’ before August 7, 1962. 

What does ‘‘in existence on August 7, 1977’’

mean? 

2. The regional haze rule defines ‘‘in 

existence’’ to mean that: 

‘‘the owner or operator has obtained all 

necessary preconstruction approvals or 

permits required by Federal, State, or local 

air pollution emissions and air quality laws 

or regulations and either has (1) begun, or 

caused to begin, a continuous program of 

physical on-site construction of the facility or 

(2) entered into binding agreements or 

contractual obligations, which cannot be 

canceled or modified without substantial loss 

to the owner or operator, to undertake a 

program of construction of the facility to be 

completed in a reasonable time.’’ 40 CFR 

51.301. 

As this definition is essentially identical to 

the definition of ‘‘commence construction’’

as that term is used in the PSD regulations, 

the two terms mean the same thing. See 40 

CFR 51.165(a)(1)(xvi) and 40 CFR 52.21(b)(9). 

Under this definition, an emissions unit 

could be ‘‘in existence’’ even if it did not 

begin operating until several years after 1977.

Example: The owner of a source obtained 

all necessary permits in early 1977 and 

entered into binding construction agreements 

in June 1977. Actual on-site construction 

began in late 1978, and construction was 

completed in mid-1979. The source began 

operating in September 1979. The emissions 

unit was ‘‘in existence’’ as of August 7, 1977.

Major stationary sources which 

commenced construction AFTER August 7, 

1977 (i.e., major stationary sources which 

were not ‘‘in existence’’ on August 7, 1977) 

were subject to new source review (NSR) 

under the PSD program. Thus, the August 7, 

1977 ‘‘in existence’’ test is essentially the 

same thing as the identification of emissions 

units that were grandfathered from the NSR 

review requirements of the 1977 CAA 

amendments.

3. Sources are not BART-eligible if the only 

change at the plant during the relevant time 

period was the addition of pollution controls. 

For example, if the only change at a copper 

smelter during the 1962 through 1977 time 

period was the addition of acid plants for the 

reduction of SO2 emissions, these emission 

controls would not by themselves trigger a 

BART review. 

What does ‘‘in operation before August 7, 

1962’’ mean? 

An emissions unit that meets the August 7, 

1977 ‘‘in existence’’ test is not BART-eligible 

if it was in operation before August 7, 1962. 

‘‘In operation’’ is defined as ‘‘engaged in 

activity related to the primary design 

function of the source.’’ This means that a 

source must have begun actual operations by 

August 7, 1962 to satisfy this test.

Example: The owner or operator entered 

into binding agreements in 1960. Actual onsite construction began in 1961, and 

construction was complete in mid-1962. The 

source began operating in September 1962. 

The emissions unit was not ‘‘in operation’’

before August 7, 1962 and is therefore subject 

to BART.

What is a ‘‘reconstructed source?’

1. Under a number of CAA programs, an 

existing source which is completely or 

39160 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

1 Fine particles: Overview of Atmospheric 

Chemistry, Sources of Emissions, and Ambient 

Monitoring Data, Memorandum to Docket OAR 

2002–006, April 1, 2005.

2Note: Most of these terms and definitions are the 

same for regional haze and the 1980 visibility 

regulations. For the regional haze rule we use the 

term ‘‘BART-eligible source’’ rather than ‘‘existing 

stationary facility’’ to clarify that only a limited 

subset of existing stationary sources are subject to 

BART.

substantially rebuilt is treated as a new 

source. Such ‘‘reconstructed’’ sources are 

treated as new sources as of the time of the 

reconstruction. Consistent with this overall 

approach to reconstructions, the definition of 

BART-eligible facility (reflected in detail in 

the definition of ‘‘existing stationary 

facility’’) includes consideration of sources 

that were in operation before August 7, 1962, 

but were reconstructed during the August 7, 

1962 to August 7, 1977 time period. 

2. Under the regional haze regulations at 40 

CFR 51.301, a reconstruction has taken place 

if ‘‘the fixed capital cost of the new 

component exceeds 50 percent of the fixed 

capital cost of a comparable entirely new 

source.’’ The rule also states that ‘‘[a]ny final 

decision as to whether reconstruction has 

occurred must be made in accordance with 

the provisions of §§ 60.15 (f)(1) through (3) of 

this title.’’ ‘‘[T]he provisions of §§ 60.15(f)(1) 

through (3)’’ refers to the general provisions 

for New Source Performance Standards 

(NSPS). Thus, the same policies and 

procedures for identifying reconstructed 

‘‘affected facilities’’ under the NSPS program 

must also be used to identify reconstructed 

‘‘stationary sources’’ for purposes of the 

BART requirement. 

3. You should identify reconstructions on 

an emissions unit basis, rather than on a 

plantwide basis. That is, you need to identify 

only the reconstructed emission units 

meeting the 50 percent cost criterion. You 

should include reconstructed emission units 

in the list of emission units you identified in 

Step 1. You need consider as possible 

reconstructions only those emissions units 

with the potential to emit more than 250 tons 

per year of any visibility-impairing pollutant. 

4. The ‘‘in operation’’ and ‘‘in existence’’

tests apply to reconstructed sources. If an 

emissions unit was reconstructed and began 

actual operation before August 7, 1962, it is 

not BART-eligible. Similarly, any emissions 

unit for which a reconstruction 

‘‘commenced’’ after August 7, 1977, is not 

BART-eligible. 

How are modifications treated under the 

BART provision? 

1. The NSPS program and the major source 

NSR program both contain the concept of 

modifications. In general, the term 

‘‘modification’’ refers to any physical change 

or change in the method of operation of an 

emissions unit that results in an increase in 

emissions. 

2. The BART provision in the regional haze 

rule contains no explicit treatment of 

modifications or how modified emissions 

units, previously subject to the requirement 

to install best available control technology 

(BACT), lowest achievable emission rate 

(LAER) controls, and/or NSPS are treated 

under the rule. As the BART requirements in 

the CAA do not appear to provide any 

exemption for sources which have been 

modified since 1977, the best interpretation 

of the CAA visibility provisions is that a 

subsequent modification does not change a 

unit’s construction date for the purpose of 

BART applicability. Accordingly, if an 

emissions unit began operation before 1962, 

it is not BART-eligible if it was modified 

between 1962 and 1977, so long as the 

modification is not also a ‘‘reconstruction.’’

On the other hand, an emissions unit which 

began operation within the 1962–1977 time 

window, but was modified after August 7, 

1977, is BART-eligible. We note, however, 

that if such a modification was a major 

modification that resulted in the installation 

of controls, the State will take this into 

account during the review process and may 

find that the level of controls already in place 

are consistent with BART. 

3. Step 3: Compare the Potential Emissions 

to the 250 Ton/Yr Cutoff 

The result of Steps 1 and 2 will be a list 

of emissions units at a given plant site, 

including reconstructed emissions units, that 

are within one or more of the BART 

categories and that were placed into 

operation within the 1962–1977 time 

window. The third step is to determine 

whether the total emissions represent a 

current potential to emit that is greater than 

250 tons per year of any single visibility 

impairing pollutant. Fugitive emissions, to 

the extent quantifiable, must be counted. In 

most cases, you will add the potential 

emissions from all emission units on the list 

resulting from Steps 1 and 2. In a few cases, 

you may need to determine whether the plant 

contains more than one ‘‘stationary source’’

as the regional haze rule defines that term, 

and as we explain further below.

What pollutants should I address? 

Visibility-impairing pollutants include the 

following: 

(1) Sulfur dioxide (SO2), 

(2) Nitrogen oxides (NOX), and 

(3) Particulate matter. 

You may use PM10 as an indicator for 

particulate matter in this intial step. [Note 

that we do not recommend use of total 

suspended particulates (TSP) as in indicator 

for particulate matter.] As emissions of PM10

include the components of PM2.5 as a subset, 

there is no need to have separate 250 ton 

thresholds for PM10 and PM2.5; 250 tons of 

PM10 represents at most 250 tons of PM2.5, 

and at most 250 tons of any individual 

particulate species such as elemental carbon, 

crustal material, etc. 

However, if you determine that a source of 

particulate matter is BART-eligible, it will be 

important to distinguish between the fine 

and coarse particle components of direct 

particulate emissions in the remainder of the 

BART analysis, including for the purpose of 

modeling the source’s impact on visibility. 

This is because although both fine and coarse 

particulate matter contribute to visibility 

impairment, the long-range transport of fine 

particles is of particular concern in the 

formation of regional haze. Thus, for 

example, air quality modeling results used in 

the BART determination will provide a more 

accurate prediction of a source’s impact on 

visibility if the inputs into the model account 

for the relative particle size of any directly 

emitted particulate matter (i.e. PM10 vs. 

PM2.5). 

You should exercise judgment in deciding 

whether the following pollutants impair 

visibility in an area: 

(4) Volatile organic compounds (VOC), and 

(5) Ammonia and ammonia compounds. 

You should use your best judgment in 

deciding whether VOC or ammonia 

emissions from a source are likely to have an 

impact on visibility in an area. Certain types 

of VOC emissions, for example, are more 

likely to form secondary organic aerosols 

than others.1 Similarly, controlling ammonia 

emissions in some areas may not have a 

significant impact on visibility. You need not 

provide a formal showing of an individual 

decision that a source of VOC or ammonia 

emissions is not subject to BART review. 

Because air quality modeling may not be 

feasible for individual sources of VOC or 

ammonia, you should also exercise your 

judgement in assessing the degree of 

visibility impacts due to emissions of VOC 

and emissions of ammonia or ammonia 

compounds. You should fully document the 

basis for judging that a VOC or ammonia 

source merits BART review, including your 

assessment of the source’s contribution to 

visibility impairment.

What does the term ‘‘potential’’ emissions 

mean? 

The regional haze rule defines potential to 

emit as follows:

‘‘Potential to emit’’ means the maximum 

capacity of a stationary source to emit a 

pollutant under its physical and operational 

design. Any physical or operational 

limitation on the capacity of the source to 

emit a pollutant including air pollution 

control equipment and restrictions on hours 

of operation or on the type or amount of 

material combusted, stored, or processed, 

shall be treated as part of its design if the 

limitation or the effect it would have on 

emissions is federally enforceable. Secondary 

emissions do not count in determining the 

potential to emit of a stationary source.

The definition of ‘‘potential to emit’’ means 

that a source which actually emits less than 

250 tons per year of a visibility-impairing 

pollutant is BART-eligible if its emissions 

would exceed 250 tons per year when 

operating at its maximum capacity given its 

physical and operational design (and 

considering all federally enforceable and 

State enforceable permit limits.)

Example: A source, while operating at onefourth of its capacity, emits 75 tons per year 

of SO2. If it were operating at 100 percent of 

its maximum capacity, the source would emit 

300 tons per year. Because under the above 

definition such a source would have 

‘‘potential’’ emissions that exceed 250 tons 

per year, the source (if in a listed category 

and built during the 1962–1977 time 

window) would be BART-eligible.

How do I identify whether a plant has more 

than one ‘‘stationary source?’’

1. The regional haze rule, in 40 CFR 

51.301, defines a stationary source as a 

‘‘building, structure, facility or installation 

which emits or may emit any air pollutant.’’ 2

Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39161

3We recognize that we are in a transition period 

from the use of the SIC system to a new system 

called the North American Industry Classification 

System (NAICS). For purposes of identifying BARTeligible sources, you may use either 2-digit SICS or 

the equivalent in the NAICS system.

4Note: The concept of support facility used for 

the NSR program applies here as well. Support 

facilities, that is facilities that convey, store or 

otherwise assist in the production of the principal 

product, must be grouped with primary facilities 

even when the facilities fall wihin separate SIC 

codes. For purposes of BART reviews, however, 

such support facilities (a) must be within one of the 

26 listed source categories and (b) must have been 

in existence as of August 7, 1977, and (c) must not 

have been in operation as of August 7, 1962.

5We expect that regional planning organizations 

will have modeling information that identifies 

sources affecting visibility in individual class I 

areas.

The rule further defines ‘‘building, structure 

or facility’’ as:

all of the pollutant-emitting activities which 

belong to the same industrial grouping, are 

located on one or more contiguous or 

adjacent properties, and are under the control 

of the same person (or persons under 

common control). Pollutant-emitting 

activities must be considered as part of the 

same industrial grouping if they belong to the 

same Major Group (i.e., which have the same 

two-digit code) as described in the Standard 

Industrial Classification Manual, 1972 as 

amended by the 1977 Supplement (U.S. 

Government Printing Office stock numbers 

4101–0066 and 003–005–00176–0, 

respectively).

2. In applying this definition, it is 

necessary to determine which facilities are 

located on ‘‘contiguous or adjacent 

properties.’’ Within this contiguous and 

adjacent area, it is also necessary to group 

those emission units that are under ‘‘common 

control.’’ We note that these plant boundary 

issues and ‘‘common control’’ issues are very 

similar to those already addressed in 

implementation of the title V operating 

permits program and in NSR. 

3. For emission units within the 

‘‘contiguous or adjacent’’ boundary and 

under common control, you must group 

emission units that are within the same 

industrial grouping (that is, associated with 

the same 2-digit SIC code) in order to define 

the stationary source.3 For most plants on the 

BART source category list, there will only be 

one 2-digit SIC that applies to the entire 

plant. For example, all emission units 

associated with kraft pulp mills are within 

SIC code 26, and chemical process plants 

will generally include emission units that are 

all within SIC code 28. The ‘‘2-digit SIC test’’

applies in the same way as the test is applied 

in the major source NSR programs.4

4. For purposes of the regional haze rule, 

you must group emissions from all emission 

units put in place within the 1962–1977 time 

period that are within the 2-digit SIC code, 

even if those emission units are in different 

categories on the BART category list.

Examples: A chemical plant which started 

operations within the 1962 to 1977 time 

period manufactures hydrochloric acid 

(within the category title ‘‘Hydrochloric, 

sulfuric, and nitric acid plants’’) and various 

organic chemicals (within the category title 

‘‘chemical process plants’’). All of the 

emission units are within SIC code 28 and, 

therefore, all the emission units are 

considered in determining BART eligibility 

of the plant. You sum the emissions over all 

of these emission units to see whether there 

are more than 250 tons per year of potential 

emissions. 

A steel mill which started operations 

within the 1962 to 1977 time period includes 

a sintering plant, a coke oven battery, and 

various other emission units. All of the 

emission units are within SIC code 33. You 

sum the emissions over all of these emission 

units to see whether there are more than 250 

tons per year of potential emissions.

4. Final Step: Identify the Emissions Units 

and Pollutants That Constitute the BARTEligible Source 

If the emissions from the list of emissions 

units at a stationary source exceed a potential 

to emit of 250 tons per year for any visibilityimpairing pollutant, then that collection of 

emissions units is a BART-eligible source.

Example: A stationary source comprises 

the following two emissions units, with the 

following potential emissions: 

Emissions unit A 

200 tons/yr SO2

150 tons/yr NOX

25 tons/yr PM 

Emissions unit B 

100 tons/yr SO2

75 tons/yr NOX

10 tons/yr PM

For this example, potential emissions of SO2

are 300 tons/yr, which exceeds the 250 tons/

yr threshold. Accordingly, the entire 

‘‘stationary source’’, that is, emissions units 

A and B, may be subject to a BART review 

for SO2, NOX, and PM, even though the 

potential emissions of PM and NOX at each 

emissions unit are less than 250 tons/yr each.

Example: The total potential emissions, 

obtained by adding the potential emissions of 

all emission units in a listed category at a 

plant site, are as follows:

200 tons/yr SO2

150 tons/yr NOX

25 tons/yr PM

Even though total emissions exceed 250 

tons/yr, no individual regulated pollutant 

exceeds 250 tons/yr and this source is not 

BART-eligible. 

Can States establish de minimis levels of 

emissions for pollutants at BART-eligible 

sources? 

In order to simplify BART determinations, 

States may choose to identify de minimis 

levels of pollutants at BART-eligible sources 

(but are not required to do so). De minimis 

values should be identified with the purpose 

of excluding only those emissions so 

minimal that they are unlikely to contribute 

to regional haze. Any de minimis values that 

you adopt must not be higher than the PSD 

applicability levels: 40 tons/yr for SO2 and 

NOX and 15 tons/yr for PM10. These de 

minimis levels may only be applied on a 

plant-wide basis. 

III. How to Identify Sources ‘‘Subject to 

BART’’

Once you have compiled your list of 

BART-eligible sources, you need to 

determine whether (1) to make BART 

determinations for all of them or (2) to 

consider exempting some of them from BART 

because they may not reasonably be 

anticipated to cause or contribute to any 

visibility impairment in a Class I area. If you 

decide to make BART determinations for all 

the BART-eligible sources on your list, you 

should work with your regional planning 

organization (RPO) to show that, collectively, 

they cause or contribute to visibility 

impairment in at least one Class I area. You 

should then make individual BART 

determinations by applying the five statutory 

factors discussed in Section IV below. 

On the other hand, you also may choose to 

perform an initial examination to determine 

whether a particular BART-eligible source or 

group of sources causes or contributes to 

visibility impairment in nearby Class I areas. 

If your analysis, or information submitted by 

the source, shows that an individual source 

or group of sources (or certain pollutants 

from those sources) is not reasonably 

anticipated to cause or contribute to any 

visibility impairment in a Class I area, then 

you do not need to make BART 

determinations for that source or group of 

sources (or for certain pollutants from those 

sources). In such a case, the source is not 

‘‘subject to BART’’ and you do not need to 

apply the five statutory factors to make a 

BART determination. This section of the 

Guideline discusses several approaches that 

you can use to exempt sources from the 

BART determination process. 

A. What Steps Do I Follow To Determine 

Whether a Source or Group of Sources Cause 

or Contribute to Visibility Impairment for 

Purposes of BART? 

1. How Do I Establish a Threshold? 

One of the first steps in determining 

whether sources cause or contribute to 

visibility impairment for purposes of BART 

is to establish a threshold (measured in 

deciviews) against which to measure the 

visibility impact of one or more sources. A 

single source that is responsible for a 1.0 

deciview change or more should be 

considered to ‘‘cause’’ visibility impairment; 

a source that causes less than a 1.0 deciview 

change may still contribute to visibility 

impairment and thus be subject to BART. 

Because of varying circumstances affecting 

different Class I areas, the appropriate 

threshold for determining whether a source 

‘‘contributes to any visibility impairment’’ for 

the purposes of BART may reasonably differ 

across States. As a general matter, any 

threshold that you use for determining 

whether a source ‘‘contributes’’ to visibility 

impairment should not be higher than 0.5 

deciviews. 

In setting a threshold for ‘‘contribution,’’

you should consider the number of emissions 

sources affecting the Class I areas at issue and 

the magnitude of the individual sources’

impacts.5 In general, a larger number of 

sources causing impacts in a Class I area may 

warrant a lower contribution threshold. 

States remain free to use a threshold lower 

than 0.5 deciviews if they conclude that the 

39162 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

6Note that the contribution threshold should be 

used to determine whether an individual source is 

reasonably anticipated to contribute to visibility 

impairment. You should not aggregate the visibility 

effects of multiple sources and compare their 

collective effects against your contribution 

threshold because this would inappropriately create 

a ‘‘contribute to contribution’’ test.

7The model code and its documentation are 

available at no cost for download from http://

www.epa.gov/scram001/tt22.htm#calpuff.

8The Guideline on Air Quality Models, 40 CFR 

part 51, appendix W, addresses the regulatory 

application of air quality models for assessing 

criteria pollutants under the CAA, and describes 

further the procedures for using the CALPUFF 

model, as well as for obtaining approval for the use 

of other, nonguideline models.

9 Interagency Workgroup on Air Quality Modeling 

(IWAQM) Phase 2 Summary Report and 

Recommendations for Modeling Long Range 

Transport Impacts, U.S. Environmental Protection 

Agency, EPA–454/R–98–019, December 1998.

location of a large number of BART-eligible 

sources within the State and in proximity to 

a Class I area justify this approach.6

2. What Pollutants Do I Need to Consider? 

You must look at SO2, NOX, and direct 

particulate matter (PM) emissions in 

determining whether sources cause or 

contribute to visibility impairment, including 

both PM10 and PM2.5. Consistent with the 

approach for identifying your BART-eligible 

sources, you do not need to consider less 

than de minimis emissions of these 

pollutants from a source. 

As explained in section II, you must use 

your best judgement to determine whether 

VOC or ammonia emissions are likely to have 

an impact on visibility in an area. In 

addition, although as explained in Section II, 

you may use PM10 an indicator for particulate 

matter in determining whether a source is 

BART-eligible, in determining whether a 

source contributes to visibility impairment, 

you should distinguish between the fine and 

coarse particle components of direct 

particulate emissions. Although both fine 

and coarse particulate matter contribute to 

visibility impairment, the long-range 

transport of fine particles is of particular 

concern in the formation of regional haze. Air 

quality modeling results used in the BART 

determination will provide a more accurate 

prediction of a source’s impact on visibility 

if the inputs into the model account for the 

relative particle size of any directly emitted 

particulate matter (i.e. PM10 vs. PM2.5).

3. What Kind of Modeling Should I Use To 

Determine Which Sources and Pollutants 

Need Not Be Subject to BART? 

This section presents several options for 

determining that certain sources need not be 

subject to BART. These options rely on 

different modeling and/or emissions analysis 

approaches. They are provided for your 

guidance. You may also use other reasonable 

approaches for analyzing the visibility 

impacts of an individual source or group of 

sources. 

Option 1: Individual Source Attribution 

Approach (Dispersion Modeling) 

You can use dispersion modeling to 

determine that an individual source cannot 

reasonably be anticipated to cause or 

contribute to visibility impairment in a Class 

I area and thus is not subject to BART. Under 

this option, you can analyze an individual 

source’s impact on visibility as a result of its 

emissions of SO2, NOX and direct PM 

emissions. Dispersion modeling cannot 

currently be used to estimate the predicted 

impacts on visibility from an individual 

source’s emissions of VOC or ammonia. You 

may use a more qualitative assessment to 

determine on a case-by-case basis which 

sources of VOC or ammonia emissions may 

be likely to impair visibility and should 

therefore be subject to BART review, as 

explained in section II.A.3. above. 

You can use CALPUFF 7 or other 

appropriate model to predict the visibility 

impacts from a single source at a Class I area. 

CALPUFF is the best regulatory modeling 

application currently available for predicting 

a single source’s contribution to visibility 

impairment and is currently the only EPAapproved model for use in estimating single 

source pollutant concentrations resulting 

from the long range transport of primary 

pollutants.8 It can also be used for some other 

purposes, such as the visibility assessments 

addressed in today’s rule, to account for the 

chemical transformation of SO2 and NOX.

There are several steps for making an 

individual source attribution using a 

dispersion model: 

1. Develop a modeling protocol. Some 

critical items to include in the protocol are 

the meteorological and terrain data that will 

be used, as well as the source-specific 

information (stack height, temperature, exit 

velocity, elevation, and emission rates of 

applicable pollutants) and receptor data from 

appropriate Class I areas. We recommend 

following EPA’s Interagency Workgroup on 

Air Quality Modeling (IWAQM) Phase 2 

Summary Report and Recommendations for 

Modeling Long Range Transport Impacts 9 for 

parameter settings and meteorological data 

inputs. You may use other settings from 

those in IWAQM, but you should identify 

these settings and explain your selection of 

these settings.

One important element of the protocol is 

in establishing the receptors that will be used 

in the model. The receptors that you use 

should be located in the nearest Class I area 

with sufficient density to identify the likely 

visibility effects of the source. For other Class 

I areas in relatively close proximity to a 

BART-eligible source, you may model a few 

strategic receptors to determine whether 

effects at those areas may be greater than at 

the nearest Class I area. For example, you 

might chose to locate receptors at these areas 

at the closest point to the source, at the 

highest and lowest elevation in the Class I 

area, at the IMPROVE monitor, and at the 

approximate expected plume release height. 

If the highest modeled effects are observed at 

the nearest Class I area, you may choose not 

to analyze the other Class I areas any further 

as additional analyses might be unwarranted. 

You should bear in mind that some 

receptors within the relevant Class I area may 

be less than 50 km from the source while 

other receptors within that same Class I area 

may be greater than 50 km from the same 

source. As indicated by the Guideline on Air 

Quality Models, 40 CFR part 51, appendix W, 

this situation may call for the use of two 

different modeling approaches for the same 

Class I area and source, depending upon the 

State’s chosen method for modeling sources 

less than 50 km. In situations where you are 

assessing visibility impacts for sourcereceptor distances less than 50 km, you 

should use expert modeling judgment in 

determining visibility impacts, giving 

consideration to both CALPUFF and other 

appropriate methods. 

In developing your modeling protocol, you 

may want to consult with EPA and your 

regional planning organization (RPO). Upfront consultation will ensure that key 

technical issues are addressed before you 

conduct your modeling.

2. With the accepted protocol and compare 

the predicted visibility impacts with your 

threshold for ‘‘contribution.’’ You should 

calculate daily visibility values for each 

receptor as the change in deciviews 

compared against natural visibility 

conditions. You can use EPA’s ‘‘Guidance for 

Estimating Natural Visibility Conditions 

Under the Regional Haze Rule,’’ EPA–454/B–

03–005 (September 2003) in making this 

calculation. To determine whether a source 

may reasonably be anticipated to cause or 

contribute to visibility impairment at Class I 

area, you then compare the impacts predicted 

by the model against the threshold that you 

have selected. 

The emissions estimates used in the 

models are intended to reflect steady-state 

operating conditions during periods of high 

capacity utilization. We do not generally 

recommend that emissions reflecting periods 

of start-up, shutdown, and malfunction be 

used, as such emission rates could produce 

higher than normal effects than would be 

typical of most facilities. We recommend that 

States use the 24 hour average actual 

emission rate from the highest emitting day 

of the meteorological period modeled, unless 

this rate reflects periods start-up, shutdown, 

or malfunction. In addition, the monthly 

average relative humidity is used, rather than 

the daily average humidity—an approach 

that effectively lowers the peak values in 

daily model averages. 

For these reasons, if you use the modeling 

approach we recommend, you should 

compare your ‘‘contribution’’ threshold 

against the 98th percentile of values. If the 

98th percentile value from your modeling is 

less than your contribution threshold, then 

you may conclude that the source does not 

contribute to visibility impairment and is not 

subject to BART. 

Option 2: Use of Model Plants To Exempt 

Individual Sources With Common 

Characteristics 

Under this option, analyses of model 

plants could be used to exempt certain 

BART-eligible sources that share specific 

characteristics. It may be most useful to use 

this type of analysis to identify the types of 

small sources that do not cause or contribute 

to visibility impairment for purposes of 

BART, and thus should not be subject to a 

BART review. Different Class I areas may 

have different characteristics, however, so 

Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39163

10CALPUFF Analysis in Support of the June 2005 

Changes to the Regional Haze Rule, U.S. 

Environmental Protection Agency, June 15, 2005, 

Docket No. OAR–2002–0076.

11That is, emission units that were in existence 

on August 7, 1977 and which began actual 

operation on or after August 7, 1962.

you should use care to ensure that the criteria 

you develop are appropriate for the 

applicable cases. 

In carrying out this approach, you could 

use modeling analyses of representative 

plants to reflect groupings of specific sources 

with important common characteristics. 

Based on these analyses, you may find that 

certain types of sources are clearly 

anticipated to cause or contribute to visibility 

impairment. You could then choose to 

categorically require those types of sources to 

undergo a BART determination. Conversely, 

you may find based on representative plant 

analyses that certain types of sources are not 

reasonably anticipated to cause or contribute 

to visibility impairment. To do this, you may 

conduct your own modeling to establish 

emission levels and distances from Class I 

areas on which you can rely to exempt 

sources with those characteristics. For 

example, based on your modeling you might 

choose to exempt all NOX-only sources that 

emit less than a certain amount per year and 

are located a certain distance from a Class I 

area. You could then choose to categorically 

exempt such sources from the BART 

determination process. 

Our analyses of visibility impacts from 

model plants provide a useful example of the 

type of analyses that can be used to exempt 

categories of sources from BART.10 In our 

analyses, we developed model plants (EGUs 

and non-EGUs), with representative plume 

and stack characteristics, for use in 

considering the visibility impact from 

emission sources of different sizes and 

compositions at distances of 50, 100 and 200 

kilometers from two hypothetical Class I 

areas (one in the East and one in the West). 

As the plume and stack characteristics of 

these model plants were developed 

considering the broad range of sources within 

the EGU and non-EGU categories, they do not 

necessarily represent any specific plant. 

However, the results of these analyses are 

instructive in the development of an 

exemption process for any Class I area.

In preparing our analyses, we have made 

a number of assumptions and exercised 

certain modeling choices; some of these have 

a tendency to lend conservatism to the 

results, overstating the likely effects, while 

others may understate the likely effects. On 

balance, when all of these factors are 

considered, we believe that our examples 

reflect realistic treatments of the situations 

being modeled. Based on our analyses, we 

believe that a State that has established 0.5 

deciviews as a contribution threshold could 

reasonably exempt from the BART review 

process sources that emit less than 500 tons 

per year of NOX or SO2 (or combined NOX

and SO2), as long as these sources are located 

more than 50 kilometers from any Class I 

area; and sources that emit less than 1000 

tons per year of NOX or SO2 (or combined 

NOX and SO2) that are located more than 100 

kilometers from any Class I area. You do, 

however, have the option of showing other 

thresholds might also be appropriate given 

your specific circumstances. 

Option 3: Cumulative Modeling To Show 

That No Sources in a State Are Subject to 

BART 

You may also submit to EPA a 

demonstration based on an analysis of overall 

visibility impacts that emissions from BARTeligible sources in your State, considered 

together, are not reasonably anticipated to 

cause or contribute to any visibility 

impairment in a Class I area, and thus no 

source should be subject to BART. You may 

do this on a pollutant by pollutant basis or 

for all visibility-impairing pollutants to 

determine if emissions from these sources 

contribute to visibility impairment. 

For example, emissions of SO2 from your 

BART-eligible sources may clearly cause or 

contribute to visibility impairment while 

direct emissions of PM2.5 from these sources 

may not contribute to impairment. If you can 

make such a demonstration, then you may 

reasonably conclude that none of your BARTeligible sources are subject to BART for a 

particular pollutant or pollutants. As noted 

above, your demonstration should take into 

account the interactions among pollutants 

and their resulting impacts on visibility 

before making any pollutant-specific 

determinations. 

Analyses may be conducted using several 

alternative modeling approaches. First, you 

may use the CALPUFF or other appropriate 

model as described in Option 1 to evaluate 

the impacts of individual sources on 

downwind Class I areas, aggregating those 

impacts to determine the collective 

contribution of all BART-eligible sources to 

visibility impairment. You may also use a 

photochemical grid model. As a general 

matter, the larger the number of sources 

being modeled, the more appropriate it may 

be to use a photochemical grid model. 

However, because such models are 

significantly less sensitive than dispersion 

models to the contributions of one or a few 

sources, as well as to the interactions among 

sources that are widely distributed 

geographically, if you wish to use a grid 

model, you should consult with the 

appropriate EPA Regional Office to develop 

an appropriate modeling protocol. 

IV. The BART Determination: Analysis of 

BART Options 

This section describes the process for the 

analysis of control options for sources subject 

to BART. 

A. What factors must I address in the BART 

review? 

The visibility regulations define BART as 

follows: 

Best Available Retrofit Technology (BART)

means an emission limitation based on the 

degree of reduction achievable through the 

application of the best system of continuous 

emission reduction for each pollutant which 

is emitted by . . . [a BART-eligible source]. 

The emission limitation must be established, 

on a case-by-case basis, taking into 

consideration the technology available, the 

costs of compliance, the energy and non-air 

quality environmental impacts of 

compliance, any pollution control equipment 

in use or in existence at the source, the 

remaining useful life of the source, and the 

degree of improvement in visibility which 

may reasonably be anticipated to result from 

the use of such technology.

The BART analysis identifies the best 

system of continuous emission reduction 

taking into account: 

(1) The available retrofit control options, 

(2) Any pollution control equipment in use 

at the source (which affects the availability 

of options and their impacts), 

(3) The costs of compliance with control 

options, 

(4) The remaining useful life of the facility, 

(5) The energy and non-air quality 

environmental impacts of control options 

(6) The visibility impacts analysis. 

B. What is the scope of the BART review? 

Once you determine that a source is subject 

to BART for a particular pollutant, then for 

each affected emission unit, you must 

establish BART for that pollutant. The BART 

determination must address air pollution 

control measures for each emissions unit or 

pollutant emitting activity subject to review.

Example: Plantwide emissions from 

emission units within the listed categories 

that began operation within the ‘‘time 

window’’ for BART 11 are 300 tons/yr of NOX, 

200 tons/yr of SO2, and 150 tons/yr of 

primary particulate. Emissions unit A emits 

200 tons/yr of NOX, 100 tons/yr of SO2, and 

100 tons/yr of primary particulate. Other 

emission units, units B through H, which 

began operating in 1966, contribute lesser 

amounts of each pollutant. For this example, 

a BART review is required for NOX, SO2, and 

primary particulate, and control options must 

be analyzed for units B through H as well as 

unit A.

C. How does a BART review relate to 

Maximum Achievable Control Technology 

(MACT) Standards under CAA section 112, 

or to other emission limitations required 

under the CAA? 

For VOC and PM sources subject to MACT 

standards, States may streamline the analysis 

by including a discussion of the MACT 

controls and whether any major new 

technologies have been developed 

subsequent to the MACT standards. We 

believe that there are many VOC and PM 

sources that are well controlled because they 

are regulated by the MACT standards, which 

EPA developed under CAA section 112. For 

a few MACT standards, this may also be true 

for SO2. Any source subject to MACT 

standards must meet a level that is as 

stringent as the best-controlled 12 percent of 

sources in the industry. Examples of these 

hazardous air pollutant sources which 

effectively control VOC and PM emissions 

include (among others) secondary lead 

facilities, organic chemical plants subject to 

the hazardous organic NESHAP (HON), 

pharmaceutical production facilities, and 

equipment leaks and wastewater operations 

at petroleum refineries. We believe that, in 

many cases, it will be unlikely that States 

will identify emission controls more 

stringent than the MACT standards without 

39164 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

12 In identifying ‘‘all’’ options, you must identify 

the most stringent option and a reasonable set of 

options for analysis that reflects a comprehensive 

list of available technologies. It is not necessary to 

list all permutations of available control levels that 

exist for a given technology—the list is complete if 

it includes the maximum level of control each 

technology is capable of achieving.

13 In EPA’s 1980 BART guidelines for reasonably 

attributable visibility impairment, we concluded 

that NSPS standards generally, at that time, 

represented the best level sources could install as 

BART. In the 20 year period since this guidance 

was developed, there have been advances in SO2

control technologies as well as technologies for the 

control of other pollutants, confirmed by a number 

of recent retrofits at Western power plants. 

Accordingly, EPA no longer concludes that the 

NSPS level of controls automatically represents 

‘‘the best these sources can install.’’ Analysis of the 

BART factors could result in the selection of a 

NSPS level of control, but you should reach this 

conclusion only after considering the full range of 

control options.

identifying control options that would cost 

many thousands of dollars per ton. Unless 

there are new technologies subsequent to the 

MACT standards which would lead to costeffective increases in the level of control, you 

may rely on the MACT standards for 

purposes of BART. 

We believe that the same rationale also 

holds true for emissions standards developed 

for municipal waste incinerators under CAA 

section 111(d), and for many NSR/PSD 

determinations and NSR/PSD settlement 

agreements. However, we do not believe that 

technology determinations from the 1970s or 

early 1980s, including new source 

performance standards (NSPS), should be 

considered to represent best control for 

existing sources, as best control levels for 

recent plant retrofits are more stringent than 

these older levels. 

Where you are relying on these standards 

to represent a BART level of control, you 

should provide the public with a discussion 

of whether any new technologies have 

subsequently become available. 

D. What Are the Five Basic Steps of a Caseby-Case BART Analysis? 

The five steps are:

STEP 1—Identify All 12 Available Retrofit 

Control Technologies,

STEP 2— Eliminate Technically Infeasible 

Options, 

STEP 3— Evaluate Control Effectiveness of 

Remaining Control Technologies, 

STEP 4— Evaluate Impacts and Document 

the Results, and 

STEP 5—Evaluate Visibility Impacts. 

1. STEP 1: How do I identify all available 

retrofit emission control techniques? 

1. Available retrofit control options are 

those air pollution control technologies with 

a practical potential for application to the 

emissions unit and the regulated pollutant 

under evaluation. Air pollution control 

technologies can include a wide variety of 

available methods, systems, and techniques 

for control of the affected pollutant. 

Technologies required as BACT or LAER are 

available for BART purposes and must be 

included as control alternatives. The control 

alternatives can include not only existing 

controls for the source category in question 

but also take into account technology transfer 

of controls that have been applied to similar 

source categories and gas streams. 

Technologies which have not yet been 

applied to (or permitted for) full scale 

operations need not be considered as 

available; we do not expect the source owner 

to purchase or construct a process or control 

device that has not already been 

demonstrated in practice. 

2. Where a NSPS exists for a source 

category (which is the case for most of the 

categories affected by BART), you should 

include a level of control equivalent to the 

NSPS as one of the control options.13 The 

NSPS standards are codified in 40 CFR part 

60. We note that there are situations where 

NSPS standards do not require the most 

stringent level of available control for all 

sources within a category. For example, postcombustion NOX controls (the most stringent 

controls for stationary gas turbines) are not 

required under subpart GG of the NSPS for 

Stationary Gas Turbines. However, such 

controls must still be considered available 

technologies for the BART selection process.

3. Potentially applicable retrofit control 

alternatives can be categorized in three ways. 

• Pollution prevention: use of inherently 

lower-emitting processes/practices, including 

the use of control techniques (e.g. low-NOX

burners) and work practices that prevent 

emissions and result in lower ‘‘productionspecific’’ emissions (note that it is not our 

intent to direct States to switch fuel forms, 

e.g. from coal to gas), 

• Use of (and where already in place, 

improvement in the performance of) add-on 

controls, such as scrubbers, fabric filters, 

thermal oxidizers and other devices that 

control and reduce emissions after they are 

produced, and 

• Combinations of inherently loweremitting processes and add-on controls. 

4. In the course of the BART review, one 

or more of the available control options may 

be eliminated from consideration because 

they are demonstrated to be technically 

infeasible or to have unacceptable energy, 

cost, or non-air quality environmental 

impacts on a case-by-case (or site-specific) 

basis. However, at the outset, you should 

initially identify all control options with 

potential application to the emissions unit 

under review.

5. We do not consider BART as a 

requirement to redesign the source when 

considering available control alternatives. 

For example, where the source subject to 

BART is a coal-fired electric generator, we do 

not require the BART analysis to consider 

building a natural gas-fired electric turbine 

although the turbine may be inherently less 

polluting on a per unit basis. 

6. For emission units subject to a BART 

review, there will often be control measures 

or devices already in place. For such 

emission units, it is important to include 

control options that involve improvements to 

existing controls and not to limit the control 

options only to those measures that involve 

a complete replacement of control devices.

Example: For a power plant with an 

existing wet scrubber, the current control 

efficiency is 66 percent. Part of the reason for 

the relatively low control efficiency is that 22 

percent of the gas stream bypasses the 

scrubber. A BART review identifies options 

for improving the performance of the wet 

scrubber by redesigning the internal 

components of the scrubber and by 

eliminating or reducing the percentage of the 

gas stream that bypasses the scrubber. Four 

control options are identified: (1) 78 percent 

control based upon improved scrubber 

performance while maintaining the 22 

percent bypass, (2) 83 percent control based 

upon improved scrubber performance while 

reducing the bypass to 15 percent, (3) 93 

percent control based upon improving the 

scrubber performance while eliminating the 

bypass entirely, (this option results in a ‘‘wet 

stack’’ operation in which the gas leaving the 

stack is saturated with water) and (4) 93 

percent as in option 3, with the addition of 

an indirect reheat system to reheat the stack 

gas above the saturation temperature. You 

must consider each of these four options in 

a BART analysis for this source.

7. You are expected to identify potentially 

applicable retrofit control technologies that 

represent the full range of demonstrated 

alternatives. Examples of general information 

sources to consider include: 

• The EPA’s Clean Air Technology Center, 

which includes the RACT/BACT/LAER 

Clearinghouse (RBLC); 

• State and Local Best Available Control 

Technology Guidelines—many agencies have 

online information—for example South Coast 

Air Quality Management District, Bay Area 

Air Quality Management District, and Texas 

Natural Resources Conservation Commission; 

• Control technology vendors; 

• Federal/State/Local NSR permits and 

associated inspection/performance test 

reports; 

• Environmental consultants; 

• Technical journals, reports and 

newsletters, air pollution control seminars; 

and 

• The EPA’s NSR bulletin board—http://

www.epa.gov/ttn/nsr;

• Department of Energy’s Clean Coal 

Program—technical reports; 

• The NOX Control Technology ‘‘Cost 

Tool’’—Clean Air Markets Division Web 

page—http://www.epa.gov/airmarkets/arp/

nox/controltech.html;

• Performance of selective catalytic 

reduction on coal-fired steam generating 

units—final report. OAR/ARD, June 1997 

(also available at http://www.epa.gov/

airmarkets/arp/nox/controltech.html); 

• Cost estimates for selected applications 

of NOX control technologies on stationary 

combustion boilers. OAR/ARD June 1997. 

(Docket for NOX SIP Call, A–96–56, item II–

A–03); 

• Investigation of performance and cost of 

NOX controls as applied to group 2 boilers. 

OAR/ARD, August 1996. (Docket for Phase II 

NOX rule, A–95–28, item IV–A–4); 

• Controlling SO2 Emissions: A Review of 

Technologies. EPA–600/R–00–093, USEPA/

ORD/NRMRL, October 2000; and 

• The OAQPS Control Cost Manual. 

You are expected to compile appropriate 

information from these information sources. 

8. There may be situations where a specific 

set of units within a fenceline constitutes the 

Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39165

logical set to which controls would apply 

and that set of units may or may not all be 

BART-eligible. (For example, some units in 

that set may not have been constructed 

between 1962 and 1977.) 

9. If you find that a BART source has 

controls already in place which are the most 

stringent controls available (note that this 

means that all possible improvements to any 

control devices have been made), then it is 

not necessary to comprehensively complete 

each following step of the BART analysis in 

this section. As long these most stringent 

controls available are made federally 

enforceable for the purpose of implementing 

BART for that source, you may skip the 

remaining analyses in this section, including 

the visibility analysis in step 5. Likewise, if 

a source commits to a BART determination 

that consists of the most stringent controls 

available, then there is no need to complete 

the remaining analyses in this section. 

2. STEP 2: How do I determine whether the 

options identified in Step 1 are technically 

feasible?

In Step 2, you evaluate the technical 

feasibility of the control options you 

identified in Step 1. You should document a 

demonstration of technical infeasibility and 

should explain, based on physical, chemical, 

or engineering principles, why technical 

difficulties would preclude the successful 

use of the control option on the emissions 

unit under review. You may then eliminate 

such technically infeasible control options 

from further consideration in the BART 

analysis. 

In general, what do we mean by technical 

feasibility? 

Control technologies are technically 

feasible if either (1) they have been installed 

and operated successfully for the type of 

source under review under similar 

conditions, or (2) the technology could be 

applied to the source under review. Two key 

concepts are important in determining 

whether a technology could be applied: 

‘‘availability’’ and ‘‘applicability.’’ As 

explained in more detail below, a technology 

is considered ‘‘available’’ if the source owner 

may obtain it through commercial channels, 

or it is otherwise available within the 

common sense meaning of the term. An 

available technology is ‘‘applicable’’ if it can 

reasonably be installed and operated on the 

source type under consideration. A 

technology that is available and applicable is 

technically feasible. 

What do we mean by ‘‘available’’ technology? 

1. The typical stages for bringing a control 

technology concept to reality as a commercial 

product are: 

• Concept stage; 

• Research and patenting; 

• Bench scale or laboratory testing; 

• Pilot scale testing; 

• Licensing and commercial 

demonstration; and 

• Commercial sales. 

2. A control technique is considered 

available, within the context presented 

above, if it has reached the stage of licensing 

and commercial availability. Similarly, we do 

not expect a source owner to conduct 

extended trials to learn how to apply a 

technology on a totally new and dissimilar 

source type. Consequently, you would not 

consider technologies in the pilot scale 

testing stages of development as ‘‘available’’

for purposes of BART review. 

3. Commercial availability by itself, 

however, is not necessarily a sufficient basis 

for concluding a technology to be applicable 

and therefore technically feasible. Technical 

feasibility, as determined in Step 2, also 

means a control option may reasonably be 

deployed on or ‘‘applicable’’ to the source 

type under consideration. 

Because a new technology may become 

available at various points in time during the 

BART analysis process, we believe that 

guidelines are needed on when a technology 

must be considered. For example, a 

technology may become available during the 

public comment period on the State’s rule 

development process. Likewise, it is possible 

that new technologies may become available 

after the close of the State’s public comment 

period and before submittal of the SIP to 

EPA, or during EPA’s review process on the 

SIP submittal. In order to provide certainty 

in the process, all technologies should be 

considered if available before the close of the 

State’s public comment period. You need not 

consider technologies that become available 

after this date. As part of your analysis, you 

should consider any technologies brought to 

your attention in public comments. If you 

disagree with public comments asserting that 

the technology is available, you should 

provide an explanation for the public record 

as to the basis for your conclusion. 

What do we mean by ‘‘applicable’’

technology? 

You need to exercise technical judgment in 

determining whether a control alternative is 

applicable to the source type under 

consideration. In general, a commercially 

available control option will be presumed 

applicable if it has been used on the same or 

a similar source type. Absent a showing of 

this type, you evaluate technical feasibility 

by examining the physical and chemical 

characteristics of the pollutant-bearing gas 

stream, and comparing them to the gas 

stream characteristics of the source types to 

which the technology had been applied 

previously. Deployment of the control 

technology on a new or existing source with 

similar gas stream characteristics is generally 

a sufficient basis for concluding the 

technology is technically feasible barring a 

demonstration to the contrary as described 

below. 

What type of demonstration is required if I 

conclude that an option is not technically 

feasible? 

1. Where you conclude that a control 

option identified in Step 1 is technically 

infeasible, you should demonstrate that the 

option is either commercially unavailable, or 

that specific circumstances preclude its 

application to a particular emission unit. 

Generally, such a demonstration involves an 

evaluation of the characteristics of the 

pollutant-bearing gas stream and the 

capabilities of the technology. Alternatively, 

a demonstration of technical infeasibility 

may involve a showing that there are 

unresolvable technical difficulties with 

applying the control to the source (e.g., size 

of the unit, location of the proposed site, 

operating problems related to specific 

circumstances of the source, space 

constraints, reliability, and adverse side 

effects on the rest of the facility). Where the 

resolution of technical difficulties is merely 

a matter of increased cost, you should 

consider the technology to be technically 

feasible. The cost of a control alternative is 

considered later in the process.

2. The determination of technical 

feasibility is sometimes influenced by recent 

air quality permits. In some cases, an air 

quality permit may require a certain level of 

control, but the level of control in a permit 

is not expected to be achieved in practice 

(e.g., a source has received a permit but the 

project was canceled, or every operating 

source at that permitted level has been 

physically unable to achieve compliance 

with the limit). Where this is the case, you 

should provide supporting documentation 

showing why such limits are not technically 

feasible, and, therefore, why the level of 

control (but not necessarily the technology) 

may be eliminated from further 

consideration. However, if there is a permit 

requiring the application of a certain 

technology or emission limit to be achieved 

for such technology, this usually is sufficient 

justification for you to assume the technical 

feasibility of that technology or emission 

limit. 

3. Physical modifications needed to resolve 

technical obstacles do not, in and of 

themselves, provide a justification for 

eliminating the control technique on the 

basis of technical infeasibility. However, you 

may consider the cost of such modifications 

in estimating costs. This, in turn, may form 

the basis for eliminating a control technology 

(see later discussion). 

4. Vendor guarantees may provide an 

indication of commercial availability and the 

technical feasibility of a control technique 

and could contribute to a determination of 

technical feasibility or technical infeasibility, 

depending on circumstances. However, we 

do not consider a vendor guarantee alone to 

be sufficient justification that a control 

option will work. Conversely, lack of a 

vendor guarantee by itself does not present 

sufficient justification that a control option or 

an emissions limit is technically infeasible. 

Generally, you should make decisions about 

technical feasibility based on chemical, and 

engineering analyses (as discussed above), in 

conjunction with information about vendor 

guarantees. 

5. A possible outcome of the BART 

procedures discussed in these guidelines is 

the evaluation of multiple control technology 

alternatives which result in essentially 

equivalent emissions. It is not our intent to 

encourage evaluation of unnecessarily large 

numbers of control alternatives for every 

emissions unit. Consequently, you should 

use judgment in deciding on those 

alternatives for which you will conduct the 

detailed impacts analysis (Step 4 below). For 

example, if two or more control techniques 

result in control levels that are essentially 

identical, considering the uncertainties of 

emissions factors and other parameters 

39166 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

14The OAQPS Control Cost Manual is updated 

periodically. While this citation refers to the latest 

version at the time this guidance was written, you 

should use the version that is current as of when 

you conduct your impact analysis. This document 

is available at the following Web site: http://

www.epa.gov/ttn/catc/dir1/cs1ch2.pdf.

15 You should include documentation for any 

additional information you used for the cost 

calculations, including any information supplied by 

vendors that affects your assumptions regarding 

purchased equipment costs, equipment life, 

replacement of major components, and any other 

element of the calculation that differs from the 

Control Cost Manual.

pertinent to estimating performance, you may 

evaluate only the less costly of these options. 

You should narrow the scope of the BART 

analysis in this way only if there is a 

negligible difference in emissions and energy 

and non-air quality environmental impacts 

between control alternatives. 

3. STEP 3: How do I evaluate technically 

feasible alternatives? 

Step 3 involves evaluating the control 

effectiveness of all the technically feasible 

control alternatives identified in Step 2 for 

the pollutant and emissions unit under 

review. 

Two key issues in this process include: 

(1) Making sure that you express the degree 

of control using a metric that ensures an 

‘‘apples to apples’’ comparison of emissions 

performance levels among options, and 

(2) Giving appropriate treatment and 

consideration of control techniques that can 

operate over a wide range of emission 

performance levels. 

What are the appropriate metrics for 

comparison? 

This issue is especially important when 

you compare inherently lower-polluting 

processes to one another or to add-on 

controls. In such cases, it is generally most 

effective to express emissions performance as 

an average steady state emissions level per 

unit of product produced or processed. 

Examples of common metrics: 

• Pounds of SO2 emissions per million Btu 

heat input, and 

• Pounds of NOX emissions per ton of 

cement produced. 

How do I evaluate control techniques with a 

wide range of emission performance levels? 

1. Many control techniques, including both 

add-on controls and inherently lower 

polluting processes, can perform at a wide 

range of levels. Scrubbers and high and low 

efficiency electrostatic precipitators (ESPs) 

are two of the many examples of such control 

techniques that can perform at a wide range 

of levels. It is not our intent to require 

analysis of each possible level of efficiency 

for a control technique as such an analysis 

would result in a large number of options. It 

is important, however, that in analyzing the 

technology you take into account the most 

stringent emission control level that the 

technology is capable of achieving. You 

should consider recent regulatory decisions 

and performance data (e.g., manufacturer’s 

data, engineering estimates and the 

experience of other sources) when 

identifying an emissions performance level 

or levels to evaluate.

2. In assessing the capability of the control 

alternative, latitude exists to consider special 

circumstances pertinent to the specific 

source under review, or regarding the prior 

application of the control alternative. 

However, you should explain the basis for 

choosing the alternate level (or range) of 

control in the BART analysis. Without a 

showing of differences between the source 

and other sources that have achieved more 

stringent emissions limits, you should 

conclude that the level being achieved by 

those other sources is representative of the 

achievable level for the source being 

analyzed. 

3. You may encounter cases where you 

may wish to evaluate other levels of control 

in addition to the most stringent level for a 

given device. While you must consider the 

most stringent level as one of the control 

options, you may consider less stringent 

levels of control as additional options. This 

would be useful, particularly in cases where 

the selection of additional options would 

have widely varying costs and other impacts. 

4. Finally, we note that for retrofitting 

existing sources in addressing BART, you 

should consider ways to improve the 

performance of existing control devices, 

particularly when a control device is not 

achieving the level of control that other 

similar sources are achieving in practice with 

the same device. For example, you should 

consider requiring those sources with 

electrostatic precipitators (ESPs) performing 

below currently achievable levels to improve 

their performance. 

4. STEP 4: For a BART review, what impacts 

am I expected to calculate and report? What 

methods does EPA recommend for the 

impacts analysis? 

After you identify the available and 

technically feasible control technology 

options, you are expected to conduct the 

following analyses when you make a BART 

determination:

Impact analysis part 1: Costs of 

compliance, 

Impact analysis part 2: Energy impacts, and 

Impact analysis part 3: Non-air quality 

environmental impacts. 

Impact analysis part 4: Remaining useful 

life.

In this section, we describe how to conduct 

each of these three analyses. You are 

responsible for presenting an evaluation of 

each impact along with appropriate 

supporting information. You should discuss 

and, where possible, quantify both beneficial 

and adverse impacts. In general, the analysis 

should focus on the direct impact of the 

control alternative. 

a. Impact analysis part 1: how do I estimate 

the costs of control? 

1. To conduct a cost analysis, you: 

(1) Identify the emissions units being 

controlled, 

(2) Identify design parameters for emission 

controls, and 

(3) Develop cost estimates based upon 

those design parameters. 

2. It is important to identify clearly the 

emission units being controlled, that is, to 

specify a well-defined area or process 

segment within the plant. In some cases, 

multiple emission units can be controlled 

jointly. However, in other cases, it may be 

appropriate in the cost analysis to consider 

whether multiple units will be required to 

install separate and/or different control 

devices. The analysis should provide a clear 

summary list of equipment and the 

associated control costs. Inadequate 

documentation of the equipment whose 

emissions are being controlled is a potential 

cause for confusion in comparison of costs of 

the same controls applied to similar sources. 

3. You then specify the control system 

design parameters. Potential sources of these 

design parameters include equipment 

vendors, background information documents 

used to support NSPS development, control 

technique guidelines documents, cost 

manuals developed by EPA, control data in 

trade publications, and engineering and 

performance test data. The following are a 

few examples of design parameters for two 

example control measures:

Control device Examples of design

parameters 

Wet Scrubbers .. Type of sorbent used (lime, 

limestone, etc.). 

Gas pressure drop. 

Liquid/gas ratio. 

Selective Catalytic Reduction.Ammonia to NOX molar 

ratio. 

Pressure drop. 

Catalyst life. 

4. The value selected for the design 

parameter should ensure that the control 

option will achieve the level of emission 

control being evaluated. You should include 

in your analysis documentation of your 

assumptions regarding design parameters. 

Examples of supporting references would 

include the EPA OAQPS Control Cost 

Manual (see below) and background 

information documents used for NSPS and 

hazardous pollutant emission standards. If 

the design parameters you specified differ 

from typical designs, you should document 

the difference by supplying performance test 

data for the control technology in question 

applied to the same source or a similar 

source. 

5. Once the control technology alternatives 

and achievable emissions performance levels 

have been identified, you then develop 

estimates of capital and annual costs. The 

basis for equipment cost estimates also 

should be documented, either with data 

supplied by an equipment vendor (i.e., 

budget estimates or bids) or by a referenced 

source (such as the OAQPS Control Cost 

Manual, Fifth Edition, February 1996, EPA 

453/B–96–001).14 In order to maintain and 

improve consistency, cost estimates should 

be based on the OAQPS Control Cost Manual,

where possible.15 The Control Cost Manual

addresses most control technologies in 

sufficient detail for a BART analysis. The 

cost analysis should also take into account 

any site-specific design or other conditions 

identified above that affect the cost of a 

particular BART technology option.

Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39167

16Whenever you calculate or report annual costs, 

you should indicate the year for which the costs are 

estimated. For example, if you use the year 2000 as 

the basis for cost comparisons, you would report 

that an annualized cost of $20 million would be: 

$20 million (year 2000 dollars).

b. What do we mean by cost effectiveness? 

Cost effectiveness, in general, is a criterion 

used to assess the potential for achieving an 

objective in the most economical way. For 

purposes of air pollutant analysis, 

‘‘effectiveness’’ is measured in terms of tons 

of pollutant emissions removed, and ‘‘cost’’

is measured in terms of annualized control 

costs. We recommend two types of costeffectiveness calculations—average cost 

effectiveness, and incremental cost 

effectiveness. 

c. How do I calculate average cost 

effectiveness? 

Average cost effectiveness means the total 

annualized costs of control divided by 

annual emissions reductions (the difference 

between baseline annual emissions and the 

estimate of emissions after controls), using 

the following formula:

Average cost effectiveness (dollars per ton 

removed) = Control option annualized 

cost 16

Baseline annual emissions—Annual 

emissions with Control option

Because you calculate costs in (annualized) 

dollars per year ($/yr) and because you 

calculate emissions rates in tons per year 

(tons/yr), the result is an average costeffectiveness number in (annualized) dollars 

per ton ($/ton) of pollutant removed. 

d. How do I calculate baseline emissions? 

1. The baseline emissions rate should 

represent a realistic depiction of anticipated 

annual emissions for the source. In general, 

for the existing sources subject to BART, you 

will estimate the anticipated annual 

emissions based upon actual emissions from 

a baseline period. 

2. When you project that future operating 

parameters (e.g., limited hours of operation 

or capacity utilization, type of fuel, raw 

materials or product mix or type) will differ 

from past practice, and if this projection has 

a deciding effect in the BART determination, 

then you must make these parameters or 

assumptions into enforceable limitations. In 

the absence of enforceable limitations, you 

calculate baseline emissions based upon 

continuation of past practice. 

3. For example, the baseline emissions 

calculation for an emergency standby 

generator may consider the fact that the 

source owner would not operate more than 

past practice of 2 weeks a year. On the other 

hand, baseline emissions associated with a 

base-loaded turbine should be based on its 

past practice which would indicate a large 

number of hours of operation. This produces 

a significantly higher level of baseline 

emissions than in the case of the emergency/

standby unit and results in more costeffective controls. As a consequence of the 

dissimilar baseline emissions, BART for the 

two cases could be very different. 

e. How do I calculate incremental cost 

effectiveness? 

1. In addition to the average cost 

effectiveness of a control option, you should 

also calculate incremental cost effectiveness. 

You should consider the incremental cost 

effectiveness in combination with the average 

cost effectiveness when considering whether 

to eliminate a control option. The 

incremental cost effectiveness calculation 

compares the costs and performance level of 

a control option to those of the next most 

stringent option, as shown in the following 

formula (with respect to cost per emissions 

reduction):

Incremental Cost Effectiveness (dollars per 

incremental ton removed) = (Total 

annualized costs of control option) ¥

(Total annualized costs of next control 

option) ÷ (Control option annual 

emissions) ¥ (Next control option 

annual emissions)

Example 1: Assume that Option F on 

Figure 2 has total annualized costs of $1 

million to reduce 2000 tons of a pollutant, 

and that Option D on Figure 2 has total 

annualized costs of $500,000 to reduce 1000 

tons of the same pollutant. The incremental 

cost effectiveness of Option F relative to 

Option D is ($1 million ¥ $500,000) divided 

by (2000 tons ¥ 1000 tons), or $500,000 

divided by 1000 tons, which is $500/ton.

Example 2: Assume that two control 

options exist: Option 1 and Option 2. Option 

1 achieves a 1,000 ton/yr reduction at an 

annualized cost of $1,900,000. This 

represents an average cost of ($1,900,000/

1,000 tons) = $1,900/ton. Option 2 achieves 

a 980 tons/yr reduction at an annualized cost 

of $1,500,000. This represents an average cost 

of ($1,500,000/980 tons) = $1,531/ton. The 

incremental cost effectiveness of Option 1 

relative to Option 2 is ($1,900,000 ¥

$1,500,000) divided by (1,000 tons ¥ 980 

tons). The adoption of Option 1 instead of 

Option 2 results in an incremental emission 

reduction of 20 tons per year at an additional 

cost of $400,000 per year. The incremental 

cost of Option 1, then, is $20,000 per ton ¥

11 times the average cost of $1,900 per ton. 

While $1,900 per ton may still be deemed 

reasonable, it is useful to consider both the 

average and incremental cost in making an 

overall cost-effectiveness finding. Of course, 

there may be other differences between these 

options, such as, energy or water use, or nonair environmental effects, which also should 

be considered in selecting a BART 

technology.

2. You should exercise care in deriving 

incremental costs of candidate control 

options. Incremental cost-effectiveness 

comparisons should focus on annualized cost 

and emission reduction differences between 

‘‘dominant’’ alternatives. To identify 

dominant alternatives, you generate a 

graphical plot of total annualized costs for 

total emissions reductions for all control 

alternatives identified in the BART analysis, 

and by identifying a ‘‘least-cost envelope’’ as 

shown in Figure 2. (A ‘‘least-cost envelope’’

represents the set of options that should be 

dominant in the choice of a specific option.)

39168 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

Example: Eight technically feasible control 

options for analysis are listed. These are 

represented as A through H in Figure 2. The 

dominant set of control options, B, D, F, G, 

and H, represent the least-cost envelope, as 

we depict by the cost curve connecting them. 

Points A, C and E are inferior options, and 

you should not use them in calculating 

incremental cost effectiveness. Points A, C 

and E represent inferior controls because B 

will buy more emissions reductions for less 

money than A; and similarly, D and F will 

buy more reductions for less money than C 

and E, respectively.

3. In calculating incremental costs, you: 

(1) Array the control options in ascending 

order of annualized total costs, 

(2) Develop a graph of the most reasonable 

smooth curve of the control options, as 

shown in Figure 2. This is to show the ‘‘leastcost envelope’’ discussed above; and 

(3) Calculate the incremental cost 

effectiveness for each dominant option, 

which is the difference in total annual costs 

between that option and the next most 

stringent option, divided by the difference in 

emissions, after controls have been applied, 

between those two control options. For 

example, using Figure 2, you would calculate 

incremental cost effectiveness for the 

difference between options B and D, options 

D and F, options F and G, and options G and 

H. 

4. A comparison of incremental costs can 

also be useful in evaluating the viability of 

a specific control option over a range of 

efficiencies. For example, depending on the 

capital and operational cost of a control 

device, total and incremental cost may vary 

significantly (either increasing or decreasing) 

over the operational range of a control 

device. Also, the greater the number of 

possible control options that exist, the more 

weight should be given to the incremental 

costs vs. average costs. It should be noted 

that average and incremental cost 

effectiveness are identical when only one 

candidate control option is known to exist. 

5. You should exercise caution not to 

misuse these techniques. For example, you 

may be faced with a choice between two 

available control devices at a source, control 

A and control B, where control B achieves 

slightly greater emission reductions. The 

average cost (total annual cost/total annual 

emission reductions) for each may be deemed 

to be reasonable. However, the incremental 

cost (total annual costA – B/total annual 

emission reductionsA – B) of the additional 

emission reductions to be achieved by 

control B may be very great. In such an 

instance, it may be inappropriate to choose 

control B, based on its high incremental 

costs, even though its average cost may be 

considered reasonable. 

6. In addition, when you evaluate the 

average or incremental cost effectiveness of a 

control alternative, you should make 

reasonable and supportable assumptions 

regarding control efficiencies. An 

unrealistically low assessment of the 

emission reduction potential of a certain 

technology could result in inflated costeffectiveness figures. 

f. What other information should I provide in 

the cost impacts analysis? 

You should provide documentation of any 

unusual circumstances that exist for the 

source that would lead to cost-effectiveness 

estimates that would exceed that for recent 

retrofits. This is especially important in cases 

where recent retrofits have cost-effectiveness 

values that are within what has been 

considered a reasonable range, but your 

analysis concludes that costs for the source 

being analyzed are not considered 

reasonable. (A reasonable range would be a 

range that is consistent with the range of cost 

effectiveness values used in other similar 

permit decisions over a period of time.)

Example: In an arid region, large amounts 

of water are needed for a scrubbing system. 

Acquiring water from a distant location could 

greatly increase the cost per ton of emissions 

reduced of wet scrubbing as a control option.

g. What other things are important to 

consider in the cost impacts analysis? 

In the cost analysis, you should take care 

not to focus on incomplete results or partial 

calculations. For example, large capital costs 

for a control option alone would not preclude 

selection of a control measure if large 

emissions reductions are projected. In such a 

case, low or reasonable cost effectiveness 

numbers may validate the option as an 

appropriate BART alternative irrespective of 

the large capital costs. Similarly, projects 

with relatively low capital costs may not be 

cost effective if there are few emissions 

reduced. 

h. Impact analysis part 2: How should I 

analyze and report energy impacts? 

1. You should examine the energy 

requirements of the control technology and 

determine whether the use of that technology 

results in energy penalties or benefits. A 

source owner may, for example, benefit from 

the combustion of a concentrated gas stream 

rich in volatile organic compounds; on the 

other hand, more often extra fuel or 

electricity is required to power a control 


ER06JY05.000</GPH>
Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39169

device or incinerate a dilute gas stream. If 

such benefits or penalties exist, they should 

be quantified to the extent practicable. 

Because energy penalties or benefits can 

usually be quantified in terms of additional 

cost or income to the source, the energy 

impacts analysis can, in most cases, simply 

be factored into the cost impacts analysis. 

The fact of energy use in and of itself does 

not disqualify a technology. 

2. Your energy impact analysis should 

consider only direct energy consumption and 

not indirect energy impacts. For example, 

you could estimate the direct energy impacts 

of the control alternative in units of energy 

consumption at the source (e.g., BTU, kWh, 

barrels of oil, tons of coal). The energy 

requirements of the control options should be 

shown in terms of total (and in certain cases, 

also incremental) energy costs per ton of 

pollutant removed. You can then convert 

these units into dollar costs and, where 

appropriate, factor these costs into the 

control cost analysis. 

3. You generally do not consider indirect 

energy impacts (such as energy to produce 

raw materials for construction of control 

equipment). However, if you determine, 

either independently or based on a showing 

by the source owner, that the indirect energy 

impact is unusual or significant and that the 

impact can be well quantified, you may 

consider the indirect impact. 

4. The energy impact analysis may also 

address concerns over the use of locally 

scarce fuels. The designation of a scarce fuel 

may vary from region to region. However, in 

general, a scarce fuel is one which is in short 

supply locally and can be better used for 

alternative purposes, or one which may not 

be reasonably available to the source either 

at the present time or in the near future. 

5. Finally, the energy impacts analysis may 

consider whether there are relative 

differences between alternatives regarding 

the use of locally or regionally available coal, 

and whether a given alternative would result 

in significant economic disruption or 

unemployment. For example, where two 

options are equally cost effective and achieve 

equivalent or similar emissions reductions, 

one option may be preferred if the other 

alternative results in significant disruption or 

unemployment. 

i. Impact analysis part 3: How do I analyze 

‘‘non-air quality environmental impacts?’’

1. In the non-air quality related 

environmental impacts portion of the BART 

analysis, you address environmental impacts 

other than air quality due to emissions of the 

pollutant in question. Such environmental 

impacts include solid or hazardous waste 

generation and discharges of polluted water 

from a control device. 

2. You should identify any significant or 

unusual environmental impacts associated 

with a control alternative that have the 

potential to affect the selection or elimination 

of a control alternative. Some control 

technologies may have potentially significant 

secondary environmental impacts. Scrubber 

effluent, for example, may affect water 

quality and land use. Alternatively, water 

availability may affect the feasibility and 

costs of wet scrubbers. Other examples of 

secondary environmental impacts could 

include hazardous waste discharges, such as 

spent catalysts or contaminated carbon. 

Generally, these types of environmental 

concerns become important when sensitive 

site-specific receptors exist or when the 

incremental emissions reductions potential 

of the more stringent control is only 

marginally greater than the next mosteffective option. However, the fact that a 

control device creates liquid and solid waste 

that must be disposed of does not necessarily 

argue against selection of that technology as 

BART, particularly if the control device has 

been applied to similar facilities elsewhere 

and the solid or liquid waste is similar to 

those other applications. On the other hand, 

where you or the source owner can show that 

unusual circumstances at the proposed 

facility create greater problems than 

experienced elsewhere, this may provide a 

basis for the elimination of that control 

alternative as BART.

3. The procedure for conducting an 

analysis of non-air quality environmental 

impacts should be made based on a 

consideration of site-specific circumstances. 

If you propose to adopt the most stringent 

alternative, then it is not necessary to 

perform this analysis of environmental 

impacts for the entire list of technologies you 

ranked in Step 3. In general, the analysis 

need only address those control alternatives 

with any significant or unusual 

environmental impacts that have the 

potential to affect the selection of a control 

alternative, or elimination of a more stringent 

control alternative. Thus, any important 

relative environmental impacts (both positive 

and negative) of alternatives can be compared 

with each other. 

4. In general, the analysis of impacts starts 

with the identification and quantification of 

the solid, liquid, and gaseous discharges from 

the control device or devices under review. 

Initially, you should perform a qualitative or 

semi-quantitative screening to narrow the 

analysis to discharges with potential for 

causing adverse environmental effects. Next, 

you should assess the mass and composition 

of any such discharges and quantify them to 

the extent possible, based on readily 

available information. You should also 

assemble pertinent information about the 

public or environmental consequences of 

releasing these materials. 

j. Impact analysis part 4: What are examples 

of non-air quality environmental impacts? 

The following are examples of how to 

conduct non-air quality environmental 

impacts: 

(1) Water Impact

You should identify the relative quantities 

of water used and water pollutants produced 

and discharged as a result of the use of each 

alternative emission control system. Where 

possible, you should assess the effect on 

ground water and such local surface water 

quality parameters as ph, turbidity, dissolved 

oxygen, salinity, toxic chemical levels, 

temperature, and any other important 

considerations. The analysis could consider 

whether applicable water quality standards 

will be met and the availability and 

effectiveness of various techniques to reduce 

potential adverse effects. 

(2) Solid Waste Disposal Impact

You could also compare the quality and 

quantity of solid waste (e.g., sludges, solids) 

that must be stored and disposed of or 

recycled as a result of the application of each 

alternative emission control system. You 

should consider the composition and various 

other characteristics of the solid waste (such 

as permeability, water retention, rewatering 

of dried material, compression strength, 

leachability of dissolved ions, bulk density, 

ability to support vegetation growth and 

hazardous characteristics) which are 

significant with regard to potential surface 

water pollution or transport into and 

contamination of subsurface waters or 

aquifers. 

(3) Irreversible or Irretrievable Commitment 

of Resources

You may consider the extent to which the 

alternative emission control systems may 

involve a trade-off between short-term 

environmental gains at the expense of longterm environmental losses and the extent to 

which the alternative systems may result in 

irreversible or irretrievable commitment of 

resources (for example, use of scarce water 

resources). 

(4) Other Adverse Environmental Impacts

You may consider significant differences in 

noise levels, radiant heat, or dissipated static 

electrical energy of pollution control 

alternatives. Other examples of non-air 

quality environmental impacts would 

include hazardous waste discharges such as 

spent catalysts or contaminated carbon. 

k. How do I take into account a project’s 

‘‘remaining useful life’’ in calculating control 

costs? 

1. You may decide to treat the requirement 

to consider the source’s ‘‘remaining useful 

life’’ of the source for BART determinations 

as one element of the overall cost analysis. 

The ‘‘remaining useful life’’ of a source, if it 

represents a relatively short time period, may 

affect the annualized costs of retrofit 

controls. For example, the methods for 

calculating annualized costs in EPA’s 

OAQPS Control Cost Manual require the use 

of a specified time period for amortization 

that varies based upon the type of control. If 

the remaining useful life will clearly exceed 

this time period, the remaining useful life has 

essentially no effect on control costs and on 

the BART determination process. Where the 

remaining useful life is less than the time 

period for amortizing costs, you should use 

this shorter time period in your cost 

calculations. 

2. For purposes of these guidelines, the 

remaining useful life is the difference 

between: 

(1) The date that controls will be put in 

place (capital and other construction costs 

incurred before controls are put in place can 

be rolled into the first year, as suggested in 

EPA’s OAQPS Control Cost Manual); you are 

conducting the BART analysis; and

(2) The date the facility permanently stops 

operations. Where this affects the BART 

determination, this date should be assured by 

a federally- or State-enforceable restriction 

preventing further operation. 

3. We recognize that there may be 

situations where a source operator intends to 

shut down a source by a given date, but 

wishes to retain the flexibility to continue 

39170 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

17The model code and its documentation are 

available at no cost for download from http://

www.epa.gov/scram001/tt22.htm#calpuff.

18 Interagency Workgroup on Air Quality 

Modeling (IWAQM) Phase 2 Summary Report and 

Recommendations for Modeling Long Range 

Transport Impacts, U.S. Environmental Protection 

Agency, EPA–454/R–98–019, December 1998.

operating beyond that date in the event, for 

example, that market conditions change. 

Where this is the case, your BART analysis 

may account for this, but it must maintain 

consistency with the statutory requirement to 

install BART within 5 years. Where the 

source chooses not to accept a federally 

enforceable condition requiring the source to 

shut down by a given date, it is necessary to 

determine whether a reduced time period for 

the remaining useful life changes the level of 

controls that would have been required as 

BART. 

If the reduced time period does change the 

level of BART controls, you may identify, 

and include as part of the BART emission 

limitation, the more stringent level of control 

that would be required as BART if there were 

no assumption that reduced the remaining 

useful life. You may incorporate into the 

BART emission limit this more stringent 

level, which would serve as a contingency 

should the source continue operating more 

than 5 years after the date EPA approves the 

relevant SIP. The source would not be 

allowed to operate after the 5-year mark 

without such controls. If a source does 

operate after the 5-year mark without BART 

in place, the source is considered to be in 

violation of the BART emissions limit for 

each day of operation. 

5. Step 5: How should I determine visibility 

impacts in the BART determination? 

The following is an approach you may use 

to determine visibility impacts (the degree of 

visibility improvement for each source 

subject to BART) for the BART 

determination. Once you have determined 

that your source or sources are subject to 

BART, you must conduct a visibility 

improvement determination for the source(s) 

as part of the BART determination. When 

making this determination, we believe you 

have flexibility in setting absolute thresholds, 

target levels of improvement, or de minimis

levels since the deciview improvement must 

be weighed among the five factors, and you 

are free to determine the weight and 

significance to be assigned to each factor. For 

example, a 0.3 deciview improvement may 

merit a stronger weighting in one case versus 

another, so one ‘‘bright line’’ may not be 

appropriate. [Note that if sources have 

elected to apply the most stringent controls 

available, consistent with the discussion in 

section E. step 1. below, you need not 

conduct, or require the source to conduct, an 

air quality modeling analysis for the purpose 

of determining its visibility impacts.] 

Use CALPUFF,17 or other appropriate 

dispersion model to determine the visibility 

improvement expected at a Class I area from 

the potential BART control technology 

applied to the source. Modeling should be 

conducted for SO2, NOX, and direct PM 

emissions (PM2.5 and/or PM10). If the source 

is making the visibility determination, you 

should review and approve or disapprove of 

the source’s analysis before making the 

expected improvement determination. There 

are several steps for determining the 

visibility impacts from an individual source 

using a dispersion model:

• Develop a modeling protocol. 

Some critical items to include in a 

modeling protocol are meteorological and 

terrain data, as well as source-specific 

information (stack height, temperature, exit 

velocity, elevation, and allowable and actual 

emission rates of applicable pollutants), and 

receptor data from appropriate Class I areas. 

We recommend following EPA’s Interagency 

Workgroup on Air Quality Modeling 

(IWAQM) Phase 2 Summary Report and 

Recommendations for Modeling Long Range 

Transport Impacts 18 for parameter settings 

and meteorological data inputs; the use of 

other settings from those in IWAQM should 

be identified and explained in the protocol.

One important element of the protocol is 

in establishing the receptors that will be used 

in the model. The receptors that you use 

should be located in the nearest Class I area 

with sufficient density to identify the likely 

visibility effects of the source. For other Class 

I areas in relatively close proximity to a 

BART-eligible source, you may model a few 

strategic receptors to determine whether 

effects at those areas may be greater than at 

the nearest Class I area. For example, you 

might chose to locate receptors at these areas 

at the closest point to the source, at the 

highest and lowest elevation in the Class I 

area, at the IMPROVE monitor, and at the 

approximate expected plume release height. 

If the highest modeled effects are observed at 

the nearest Class I area, you may choose not 

to analyze the other Class I areas any further 

as additional analyses might be unwarranted.

You should bear in mind that some 

receptors within the relevant Class I area may 

be less than 50 km from the source while 

other receptors within that same Class I area 

may be greater than 50 km from the same 

source. As indicated by the Guideline on Air 

Quality Models, this situation may call for 

the use of two different modeling approaches 

for the same Class I area and source, 

depending upon the State’s chosen method 

for modeling sources less than 50 km. In 

situations where you are assessing visibility 

impacts for source-receptor distances less 

than 50 km, you should use expert modeling 

judgment in determining visibility impacts, 

giving consideration to both CALPUFF and 

other EPA-approved methods. 

In developing your modeling protocol, you 

may want to consult with EPA and your 

regional planning organization (RPO). Upfront consultation will ensure that key 

technical issues are addressed before you 

conduct your modeling. 

• For each source, run the model, at precontrol and post-control emission rates 

according to the accepted methodology in the 

protocol. 

Use the 24-hour average actual emission 

rate from the highest emitting day of the 

meteorological period modeled (for the precontrol scenario). Calculate the model results 

for each receptor as the change in deciviews 

compared against natural visibility 

conditions. Post-control emission rates are 

calculated as a percentage of pre-control 

emission rates. For example, if the 24-hr precontrol emission rate is 100 lb/hr of SO2, 

then the post control rate is 5 lb/hr if the 

control efficiency being evaluated is 95 

percent. 

• Make the net visibility improvement 

determination. 

Assess the visibility improvement based on 

the modeled change in visibility impacts for 

the pre-control and post-control emission 

scenarios. You have flexibility to assess 

visibility improvements due to BART 

controls by one or more methods. You may 

consider the frequency, magnitude, and 

duration components of impairment. 

Suggestions for making the determination 

are: 

• Use of a comparison threshold, as is 

done for determining if BART-eligible 

sources should be subject to a BART 

determination. Comparison thresholds can be 

used in a number of ways in evaluating 

visibility improvement (e.g. the number of 

days or hours that the threshold was 

exceeded, a single threshold for determining 

whether a change in impacts is significant, or 

a threshold representing an x percent change 

in improvement). 

• Compare the 98th percent days for the 

pre- and post-control runs. 

Note that each of the modeling options 

may be supplemented with source 

apportionment data or source apportionment 

modeling. 

E. How do I select the ‘‘best’’ alternative, 

using the results of Steps 1 through 5? 

1. Summary of the Impacts Analysis 

From the alternatives you evaluated in 

Step 3, we recommend you develop a chart 

(or charts) displaying for each of the 

alternatives: 

(1) Expected emission rate (tons per year, 

pounds per hour); 

(2) Emissions performance level (e.g., 

percent pollutant removed, emissions per 

unit product, lb/MMBtu, ppm); 

(3) Expected emissions reductions (tons 

per year); 

(4) Costs of compliance—total annualized 

costs ($), cost effectiveness ($/ton), and 

incremental cost effectiveness ($/ton), and/or 

any other cost-effectiveness measures (such 

as $/deciview); 

(5) Energy impacts; 

(6) Non-air quality environmental impacts; 

and 

(7) Modeled visibility impacts. 

2. Selecting a ‘‘best’’ alternative 

1. You have discretion to determine the 

order in which you should evaluate control 

options for BART. Whatever the order in 

which you choose to evaluate options, you 

should always (1) display the options 

evaluated; (2) identify the average and 

incremental costs of each option; (3) consider 

the energy and non-air quality environmental 

impacts of each option; (4) consider the 

remaining useful life; and (5) consider the 

modeled visibility impacts. You should 

provide a justification for adopting the 

technology that you select as the ‘‘best’’ level 

of control, including an explanation of the 

Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 39171

CAA factors that led you to choose that 

option over other control levels. 

2. In the case where you are conducting a 

BART determination for two regulated 

pollutants on the same source, if the result 

is two different BART technologies that do 

not work well together, you could then 

substitute a different technology or 

combination of technologies. 

3. In selecting a ‘‘best’’ alternative, should I 

consider the affordability of controls?

1. Even if the control technology is cost 

effective, there may be cases where the 

installation of controls would affect the 

viability of continued plant operations. 

2. There may be unusual circumstances 

that justify taking into consideration the 

conditions of the plant and the economic 

effects of requiring the use of a given control 

technology. These effects would include 

effects on product prices, the market share, 

and profitability of the source. Where there 

are such unusual circumstances that are 

judged to affect plant operations, you may 

take into consideration the conditions of the 

plant and the economic effects of requiring 

the use of a control technology. Where these 

effects are judged to have a severe impact on 

plant operations you may consider them in 

the selection process, but you may wish to 

provide an economic analysis that 

demonstrates, in sufficient detail for public 

review, the specific economic effects, 

parameters, and reasoning. (We recognize 

that this review process must preserve the 

confidentiality of sensitive business 

information). Any analysis may also consider 

whether other competing plants in the same 

industry have been required to install BART 

controls if this information is available. 

4. Sulfur dioxide limits for utility boilers 

You must require 750 MW power plants to 

meet specific control levels for SO2 of either 

95 percent control or 0.15 lbs/MMBtu, for 

each EGU greater than 200 MW that is 

currently uncontrolled unless you determine 

that an alternative control level is justified 

based on a careful consideration of the 

statutory factors. Thus, for example, if the 

source demonstrates circumstances affecting 

its ability to cost-effectively reduce its 

emissions, you should take that into account 

in determining whether the presumptive 

levels of control are appropriate for that 

facility. For a currently uncontrolled EGU 

greater than 200 MW in size, but located at 

a power plant smaller than 750 MW in size, 

such controls are generally cost-effective and 

could be used in your BART determination 

considering the five factors specified in CAA 

section 169A(g)(2). While these levels may 

represent current control capabilities, we 

expect that scrubber technology will 

continue to improve and control costs 

continue to decline. You should be sure to 

consider the level of control that is currently 

best achievable at the time that you are 

conducting your BART analysis. 

For coal-fired EGUs with existing postcombustion SO2 controls achieving less than 

50 percent removal efficiencies, we 

recommend that you evaluate constructing a 

new FGD system to meet the same emission 

limits as above (95 percent removal or 0.15 

lb/mmBtu), in addition to the evaluation of 

scrubber upgrades discussed below. For oilfired units, regardless of size, you should 

evaluate limiting the sulfur content of the 

fuel oil burned to 1 percent or less by weight. 

For those BART-eligible EGUs with preexisting post-combustion SO2 controls 

achieving removal efficiencies of at least 50 

percent, your BART determination should 

consider cost effective scrubber upgrades 

designed to improve the system’s overall SO2

removal efficiency. There are numerous 

scrubber enhancements available to upgrade 

the average removal efficiencies of all types 

of existing scrubber systems. We recommend 

that as you evaluate the definition of 

‘‘upgrade,’’ you evaluate options that not 

only improve the design removal efficiency 

of the scrubber vessel itself, but also consider 

upgrades that can improve the overall SO2

removal efficiency of the scrubber system. 

Increasing a scrubber system’s reliability, and 

conversely decreasing its downtime, by way 

of optimizing operation procedures, 

improving maintenance practices, adjusting 

scrubber chemistry, and increasing auxiliary 

equipment redundancy, are all ways to 

improve average SO2 removal efficiencies. 

We recommend that as you evaluate the 

performance of existing wet scrubber 

systems, you consider some of the following 

upgrades, in no particular order, as potential 

scrubber upgrades that have been proven in 

the industry as cost effective means to 

increase overall SO2 removal of wet systems: 

(a) Elimination of Bypass Reheat; 

(b) Installation of Liquid Distribution 

Rings; 

(c) Installation of Perforated Trays; 

(d) Use of Organic Acid Additives; 

(e) Improve or Upgrade Scrubber Auxiliary 

System Equipment; 

(f) Redesign Spray Header or Nozzle 

Configuration. 

We recommend that as you evaluate 

upgrade options for dry scrubber systems, 

you should consider the following cost 

effective upgrades, in no particular order: 

(a) Use of Performance Additives; 

(b) Use of more Reactive Sorbent; 

(c) Increase the Pulverization Level of 

Sorbent; 

(d) Engineering redesign of atomizer or 

slurry injection system. 

You should evaluate scrubber upgrade 

options based on the 5 step BART analysis 

process. 

5. Nitrogen oxide limits for utility boilers

You should establish specific numerical 

limits for NOX control for each BART 

determination. For power plants with a 

generating capacity in excess of 750 MW 

currently using selective catalytic reduction 

(SCR) or selective non-catalytic reduction 

(SNCR) for part of the year, you should 

presume that use of those same controls yearround is BART. For other sources currently 

using SCR or SNCR to reduce NOX emissions 

during part of the year, you should carefully 

consider requiring the use of these controls 

year-round as the additional costs of 

operating the equipment throughout the year 

would be relatively modest. 

For coal-fired EGUs greater than 200 MW 

located at greater than 750 MW power plants 

and operating without post-combustion 

controls (i.e. SCR or SNCR), we have 

provided presumptive NOX limits, 

differentiated by boiler design and type of 

coal burned. You may determine that an 

alternative control level is appropriate based 

on a careful consideration of the statutory 

factors. For coal-fired EGUs greater than 200 

MW located at power plants 750 MW or less 

in size and operating without postcombustion controls, you should likewise 

presume that these same levels are costeffective. You should require such utility 

boilers to meet the following NOX emission 

limits, unless you determine that an 

alternative control level is justified based on 

consideration of the statutory factors. The 

following NOX emission rates were 

determined based on a number of 

assumptions, including that the EGU boiler 

has enough volume to allow for installation 

and effective operation of separated overfire 

air ports. For boilers where these 

assumptions are incorrect, these emission 

limits may not be cost-effective.

39172 Federal Register / Vol. 70, No. 128 / Wednesday, July 6, 2005 / Rules and Regulations 

19No Cell burners, dry-turbo-fired units, nor wetbottom tangential-fired units burning lignite were 

identified as BART-eligible, thus no presumptive 

limit was determined. Similarly, no wet-bottom 

tangential-fired units burning sub-bituminous were 

identified as BART-eligible.

20These limits reflect the design and 

technological assumptions discussed in the 

technical support document for NOX limits for 

these guidelines. See Technical Support Document 

for BART NOX Limits for Electric Generating Units 

and Technical Support Document for BART NOX

Limits for Electric Generating Units Excel 

Spreadsheet, Memorandum to Docket OAR 2002–

0076, April 15, 2005.

21See Technical Support Document for BART 

NOX Limits for Electric Generating Units and 

Technical Support Document for BART NOX Limits 

for Electric Generating Units Excel Spreadsheet,

Memorandum to Docket OAR 2002–0076, April 15, 

2005. 22 70 FR 9705, February 28, 2005.

TABLE 1.—PRESUMPTIVE NOX EMISSION LIMITS FOR BART-ELIGIBLE COAL-FIRED UNITS.19

Unit type Coal type 

NOX presumptive 

limit

(lb/mmbtu) 20

Dry-bottom wall-fired ................................................................. Bituminous ................................................................................ 0.39 

Sub-bituminous ........................................................................ 0.23 

Lignite ....................................................................................... 0.29 

Tangential-fired ......................................................................... Bituminous ................................................................................ 0.28 

Sub-bituminous ........................................................................ 0.15 

Lignite ....................................................................................... 0.17 

Cell Burners .............................................................................. Bituminous ................................................................................ 0.40 

Sub-bituminous ........................................................................ 0.45 

Dry-turbo-fired ........................................................................... Bituminous ................................................................................ 0.32 

Sub-bituminous ........................................................................ 0.23 

Wet-bottom tangential-fired ...................................................... Bituminous ................................................................................ 0.62 

MostEGUs can meet these presumptive 

NO X limits through the use of current 

combustion control technology, i.e. the 

careful control of combustion air and lowNOX burners. For units that cannot meet 

these limits using such technologies, you 

should consider whether advanced 

combustion control technologies such as 

rotating opposed fire air should be used to 

meet these limits.

Because of the relatively high NOX

emission rates of cyclone units, SCR is more 

cost-effective than the use of current 

combustion control technology for these 

units. The use of SCRs at cyclone units 

burning bituminous coal, sub-bituminous 

coal, and lignite should enable the units to 

cost-effectively meet NOX rates of 0.10 lbs/

mmbtu. As a result, we are establishing a 

presumptive NOX limit of 0.10 lbs/mmbtu 

based on the use of SCR for coal-fired 

cyclone units greater than 200 MW located at 

750 MW power plants. As with the other 

presumptive limits established in this 

guideline, you may determine that an 

alternative level of control is appropriate 

based on your consideration of the relevant 

statutory factors. For other cyclone units, you 

should review the use of SCR and consider 

whether these post-combustion controls 

should be required as BART. 

For oil-fired and gas-fired EGUs larger than 

200MW, we believe that installation of 

current combustion control technology to 

control NOX is generally highly cost-effective 

and should be considered in your 

determination of BART for these sources. 

Many such units can make significant 

reductions in NOX emissions which are 

highly cost-effective through the application 

of current combustion control technology.21

V. Enforceable Limits/Compliance Date 

To complete the BART process, you must 

establish enforceable emission limits that 

reflect the BART requirements and require 

compliance within a given period of time. In 

particular, you must establish an enforceable 

emission limit for each subject emission unit 

at the source and for each pollutant subject 

to review that is emitted from the source. In 

addition, you must require compliance with 

the BART emission limitations no later than 

5 years after EPA approves your regional 

haze SIP. If technological or economic 

limitations in the application of a 

measurement methodology to a particular 

emission unit make a conventional emissions 

limit infeasible, you may instead prescribe a 

design, equipment, work practice, operation 

standard, or combination of these types of 

standards. You should consider allowing 

sources to ‘‘average’’ emissions across any set 

of BART-eligible emission units within a 

fenceline, so long as the emission reductions 

from each pollutant being controlled for 

BART would be equal to those reductions 

that would be obtained by simply controlling 

each of the BART-eligible units that 

constitute BART-eligible source. 

You should ensure that any BART 

requirements are written in a way that clearly 

specifies the individual emission unit(s) 

subject to BART regulation. Because the 

BART requirements themselves are 

‘‘applicable’’ requirements of the CAA, they 

must be included as title V permit conditions 

according to the procedures established in 40 

CFR part 70 or 40 CFR part 71. 

Section 302(k) of the CAA requires 

emissions limits such as BART to be met on 

a continuous basis. Although this provision 

does not necessarily require the use of 

continuous emissions monitoring (CEMs), it 

is important that sources employ techniques 

that ensure compliance on a continuous 

basis. Monitoring requirements generally 

applicable to sources, including those that 

are subject to BART, are governed by other 

regulations. See, e.g., 40 CFR part 64 

(compliance assurance monitoring); 40 CFR 

70.6(a)(3) (periodic monitoring); 40 CFR 

70.6(c)(1) (sufficiency monitoring). Note also 

that while we do not believe that CEMs 

would necessarily be required for all BART 

sources, the vast majority of electric 

generating units potentially subject to BART 

already employ CEM technology for other 

programs, such as the acid rain program. In 

addition, emissions limits must be 

enforceable as a practical matter (contain 

appropriate averaging times, compliance 

verification procedures and recordkeeping 

requirements). In light of the above, the 

permit must: 

• Be sufficient to show compliance or 

noncompliance (i.e., through monitoring 

times of operation, fuel input, or other 

indices of operating conditions and 

practices); and 

• Specify a reasonable averaging time 

consistent with established reference 

methods, contain reference methods for 

determining compliance, and provide for 

adequate reporting and recordkeeping so that 

air quality agency personnel can determine 

the compliance status of the source; and 

• For EGUS, specify an averaging time of 

a 30-day rolling average, and contain a 

definition of ‘‘boiler operating day’’ that is 

consistent with the definition in the 

proposed revisions to the NSPS for utility 

boilers in 40 CFR Part 60, subpart Da.22 You 

should consider a boiler operating day to be 

any 24-hour period between 12:00 midnight 

and the following midnight during which 

any fuel is combusted at any time at the 

steam generating unit. This would allow 30-

day rolling average emission rates to be 

calculated consistently across sources.

[FR Doc. 05–12526 Filed 7–5–05; 8:45 am] 

BILLING CODE 6560–50–P

Attachment	5	

Intalco	Primary	Phone	Log	–	Zach	Hedgpeth	

Date Person Topic

9/7/11	 Don	Hug,	Allied	Env.	 Dry	scrubbing	temp	requirements.	

9/7/11	 Kathryn	Mitchell,	Intalco	

Jimmy	Jones,	Alcoa	

Obtaining	Alstom	&	Babcock	quote	docs.	

9/20/11	 Kathryn	Mitchell,	Intalco	 Existing	wastewater	treatment	facilities	for	

roofline	scrubbers.	

11/16/11	 Kyle	Murphy,	WA	DNR	 Studies	required	under	Cherry	Pt	Plan.		

Discussion	of	DNR	aquatic	leases	in	general.	

11/18/11	 Kyle	Murphy,	WA	DNR	 Current	Intalco	aquatic	lease	documents.		

Outfall	location.		General	lease	requirements.	

11/22/11	 Randy	Marshall,	Ecology	 Studies	required	under	Cherry	Pt	Plan.	

11/22/11	 Kyle	Murphy,	WA	DNR	 Studies	required	under	Cherry	Pt	Plan.	

11/28/11	 Linda	Martin,	KYDEP	 Rio	Tinto	Alcan	plant	wet	scrubbing	cost	

analysis.	

12/2/11	 Ben	Girtain‐Plowe,	NYDEC	 West	Massena	plant	documents.	

12/2/11	 Kathryn	Mitchell,	Intalco	

Jimmy	Jones,	Alcoa	

Alstom	&	Babcock	quotes.		Wastewater	

stream	expected	from	LSFO	per	quote	docs.		

Current	mini‐scrubbers	on	roofline.	

12/8/11	 Stephen	Jilk,	Whatcom	PUD	 PUD	ability	to	provide	500k	gpd	increased	

supply	to	Intalco,	and	related	fees.	

12/9/11	 Judy	Schweiters,	Ecology	 Intalco	BART	in	general.	

1/6/12	 Judy	Schweiters,	Ecology	 Existing	wastewater	infrastructure.	

1/10/12	 Randy	Hamilton,	TCEQ	 Permit	for	Oak	Grove	boiler	with	LSFO.	

3/20/12	 Clint	Lamoreaux,	SWCAA	 LSFO	costs	at	TransAlta.		Contact	with	

TransAlta.	

6/20/12	 Jimmy	Jones,	Alcoa	 EPA	cost	analysis	and	technical	basis.	

7/19/12	 Jimmy	Jones,	Alcoa	 Alcoa	cost	scaling	approach	for	partial	

scrubbing.	




Re: Zach's contact info -- Massena East permit 

Zach Hedgpeth to: Robert Jacobs 01/10/2012 11:26 AM

Bob,

Thanks for your thoughts and the wastewater update. I'd enjoy talking this aspect over further with you, 

since our potential project has some noteworthy differences from Massena.

Give me a call sometime if this interests you,

Zach

-------------------------------------------------------------

Zach Hedgpeth, PE

EPA Region 10

Office of Environmental Assessment

(206) 553-1217

hedgpeth.zach@epa.gov

"Robert Jacobs" Not a problem. On a side note, the scrubber in u... 01/10/2012 10:58:55 AM

From: "Robert Jacobs" <rxjacobs@gw.dec.state.ny.us>

To: Zach Hedgpeth/R10/USEPA/US@EPA

Cc: "Steve Botsford" <srbotsfo@gw.dec.state.ny.us>, "Thomas Morgan" 

<tfmorgan@gw.dec.state.ny.us>

Date: 01/10/2012 10:58 AM

Subject: Re: Zach's contact info -- Massena East permit

Not a problem. 

On a side note, the scrubber in use in Massena is not without it's problems. 

The unit is fine for removing the sulfur, but it also picks up some of the 

fluorides. I don't know the details because this falls under our water 

resources division, but with the EPA Water Quality regulations, the facility 

is having problems meeting the water quality standards for fluorides. My 

understanding is once it's in the water, there's no efficient way of removing. 

So, it could be a matter of trading one problem for another if a facility were 

made to install a scrubber.

Something to consider. 

Thanks.

Bob

>>> Zach Hedgpeth <Hedgpeth.Zach@epamail.epa.gov> 1/10/2012 1:34 PM >>>

I really appreciate the fast action Bob,

Zach
From: "Robert Jacobs" <rxjacobs@gw.dec.state.ny.us>

To: Zach Hedgpeth/R10/USEPA/US@EPA

Date: 01/10/2012 10:27 AM

Subject: Re: Zach's contact info -- Massena East permit

Zach,

Attached is the Title V permit issued for the construction and operation 

of the Alcoa owned Reynolds Plant in Massena NY. 

Let me know if you need anything else.

Bob Jacobs

315-785-6457

NYS DEC Region 6

Watertown, NY

>>> Zach Hedgpeth <Hedgpeth.Zach@epamail.epa.gov> 1/10/2012 1:11 PM >>>

Here you are....thanks again Bob.

Zach

-------------------------------------------------------------

Zach Hedgpeth, PE

EPA Region 10

Office of Environmental Assessment

(206) 553-1217

hedgpeth.zach@epa.gov 

[attachment "Reynolds Metals Massena NY Facility Title V permit 1999.pdf" 

deleted by Zach Hedgpeth/R10/USEPA/US] 
New York State Department of Environmental Conservation 

Division of Environmental Permits, Region 6 

• Dulles State Office Building, 317 Washington Street, Watertown, New York 13601-3787 

Phone: (315) 785-2245 • FAX: (315) 785-2242 ~,.,-..~ ~) f:,-'1 ;,'• 

Website: www .dec.state.ny. us 

. \ Alexander B. Grannis 

Commissioner 

CERTIFIED MAIL • RETURN RECEIPT REQUESTED 

September 18, 2007 

REYNOLDS METALS COMPANY 

ALCOA-EAST 

Attn: Mr. Wesley N. Oberholzer, Location Manager 

P. 0. Box 500 

Massena, NY 13662 

BUREAU OF WATER PERMITS o;cc".'~n 

SEP 2 0 2007 

RE: MODIFICATION TO SPDES PERMIT #NY0000132; DEC #6-4058-00024/00001 

ALCOA-EAST. (T) MASSENA. ST. LAWRENCE COUNTY. 

Dear Mr. Oberholzer: 

This is to inform you that pursuant to Article 17, Title 8 of the Environmental Conservation Law 

and 6NYCRR Part 757, the Department has made a determination to modify the permit 

referenced above as indicated in the following enclosed revised permit (pages 1-28). This revised 

permit supersedes the previous corresponding permit. This modification will be come effe1ctive 

October 1 , 2007. 

The permit is being modified to revise the Outfall 002 construction compliance dates; correct the 

WTC page relative to current usage; and to reference the correct name of the current 

Environmental Manager (revisions to pages 1, 15, 23, and 26). 

If you have any questions, you may contact me at 315-785-2245 or Ann Rice at 315-785-2513. 

S~n,rely, i /) /_ u 

~nM-tetU~ 

Lawrence R. Ambeau 

Regional Permit Administrator 

Region 6 

LRA:ACR:sgs 

Enclosure 

cc: Charles Dobbs, ALCOA, w/enc. 

T.-homas Lightfoot, ALCOA, w/enc. 

vAian Fuchs, BWP, Albany, w/enc. 

Shayne Mitchell, BWP, w/enc. 

NYSDOH, Canton, w/enc. 

USEPA, Region II, w/enc. 

Ann Rice/SPDES File, w/enc. 
Industrial Code: 

Discharge Class (CL): 

Toxic Class (TX): 

Major Drainage Basin: 

Sub Drainage Basin: 

Water Index Number: 

Compact Area: 

NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL CONSERVATION 

State Pollutant Discharge Elimination System (SPDES) 

DISCHARGE PERMIT 

3334 

03 

T 

09 

01,03 

SL, SL-1 

Special Conditions (Part 1) 

SPDES Number: 

DEC Number: 

Effective Date (EDP): 

Expiration Date (ExDP): 

Modification Dates: 

NY- 0000132 

6-4058-00024/00001 

06/01/04 

06/01/09 

10/01107 

first3.00 

This SPDES permit is issued in compliance with Title 8 of Article 17 of the Environmental Conservation Law of New York 

State and in compliance with the Clean Water Act, as amended, (33 U.S.C. §1251 et.seq.)(hereinafter referred to as "the Act"). 

PERMITTEE NAME AND ADDRESS j) 0 

Name: Reynolds Metals Compan~'+ ~" ' 

Street: 201 Isabella Street ' l ,p & 

Attention: Smelting Operations Manager 

City: Pittsburgh State: PA Zip Code: ·15212-5858: 

is authorized to discharge from the facility described below: 

FACILITY NAME AND ADDRESS 

Name: 

Location (C,T,V): 

Facility Address: 

City: 

NYTM-E: 

Alcoa -East 

Massena (T) 

194 County Route 45 

Massena 

From Outfall No.: 001 at Latitude: 44 o 

into receiving waters known as: St. Lawrence River 

and; (list other Outfalls, Receiving Waters & Water Classifications) 

002, 003, 005, & 008 

010 & 011 

St. Lawrence River 

Raquette River 

59 I 

County: 

State: NY 

NYTM-N: 

St. Lawrence 

Zip Code: 13662 

10 " & Longitude: 74 o 44 , 

Class A 

Class B 

Class: A 

50 If 

in accordance with: effluent limitations; monitoring and reporting requirements; other provisions and conditions set forth this permit; 

and 6 NYCRR Part 750-1.2(a) and 750-2. 

DISCHARGE MONITORING REPORT (DMR) MAILING ADDRESS 

Mailing Name: Alcoa, Inc. 

Street: P.O. Box 150 

City: Massena State: NY Zip Code: 13662 

Responsible Official or Agent: Charles Dobbs, Environmental Manager Phone: 315-764-4642 

This permit and the authorization to discharge shall expire on midnight of the expiration date shown above and the permittee shall 

not discharge after the expiration date unless this permit has been renewed, or extended pursuant to law. To be authorized to discharge 

beyond the expiration date, the permittee shall apply for permit renewal not less than 180 days prior to the expiration date shown above. 

DISTRJBUTION: 

Bureau of Water Permits 

NYSDOH, Canton 

USEP A Region II 

SPDES File 

Permit Administrator: Lawrence R. Ambeau, Region 6 

Address: 317 Washington Street 

Watertwon, New York 13601 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 2 of 28 

PERMIT LIMITS, LEVELS AND MONITORING DEFINITIONS 

C:\MvFiles\0000132o.07m()(I.$1Y1.wnd 

OUTFALL WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRING 

This cell describes the type of wastewater authorized This cell lists classified The date this page The date this page 

for discharge. Examples include process or sanitary waters of the state to which starts in effect. (e.g. is no longer in 

wastewater, storm water, non-contact cooling water. the listed outfall discharges. EDPorEDPM) effect. (e.g. ExDP) 

!PARAMETER MINIMUM MAXIMUM UNITS SAMPLE FREQ. SAMPLE TYPE 

e.g. pH, TRC, The minimum level that must be The maximum level that may not SU, °F, 

~emperature, D.O. maintained at all instants in time. be exceeded at any instant in time. mg/1, etc. 

PARA- EFFLUENT LIMIT PRACTICAL QUANTITA TION ACTION UNITS SAMPLE SAMPLE 

[METER LIMIT(PQL) LEVEL FREQUENCY TYPE 

Limit types are defined below in For the purposes of compliance Type I or This can Examples Exarnples 

Note I. The effluent limit is assessment, the analytical method Type II include units include Daily, include 

developed based on the more specified in the permit shall be used Action Levels of flow, pH, 3/week, grab, 24 

stringent oftechnology-based limits, to monitor the amount of the are mass, weekly, hour 

required under the Clean Water Act, pollutant in the outfall to this level, monitoring Temperature, 2/month, composite 

or New York State water quality provided that the labpratory analyst requirements, concentration. monthly, and 3 grab 

standards. The limit has been has complied with the specified as defined Examples quarterly, 2/yr samples 

derived based on existing quality assurance/quality control below in Note include !J.g/1, and yearly. collected 

assumptions and rules. These procedures in the relevant method. 2, that trigger lbs/d, etc. over a 6 

assumptions include receiving water Monitoring results that are lower additional hour 

hardness, pH and temperature; rates than this level must be reported, but monitoring period. 

of this and other discharges to the shall not be used to determine and permit 

receiving stream; etc. If assumptions compliance with the calculated limit. review when 

or rules change the limit may, after This PQL can be neither lowered exceeded. 

due process and modification of this nor raised without a modification of 

I permit, change. this permit. 

Note 1: DAILY DISCHARGE.: The discharge of a pollutant measured during a calendar day or any 24-hour period that reasonably represents the calendar 

day for the purposes of sampling. For pollutants expressed in units of mass, the 'daily discharge' is calculated as the total mass of the pollutant discharged 

over the day. For pollutants with limitations expressed in other units of measurement, the 'daily discharge' is calculated as the average measurement of 

the pollutant over the day. 

DAILY MAX.: The highest allowable daily discharge. DAILY MIN.: The lowest allowable daily discharge. 

MONTHLY A VG: The highest allowable average of daily discharges over a calendar month, calculated as the sum of each of the daily discharges 

measured during a calendar month divided by the number of daily discharges measured during that month. 

7 DAY ARITHMETIC MEAN (7 day average): The highest allowable average of daily discharges over a calendar week. 

30 DAY GEOMETRIC MEAN: The highest allowable geometric mean of daily discharges over a calendar month, calculated as the antilog of: the sum 

of the log of each of the daily discharges measured during a calendar month divided by the number of daily discharges measured during that montl}. 

7 DAY GEOMETRIC MEAN: The highest allowable geometric mean of daily discharges over a calendar week. 

RANGE: The minimum and maximum instantaneous measurements for the reporting period must remain between the two values shown. 

Note 2: ACTION LEVELS: Routine Action Level monitoring results, if not provided for on the Discharge Monitoring Report (DMR) form, shall be 

appended to the DMR for the period during which the sampling was conducted. If the additional monitoring requirement is triggered as noted below, 

the permittee shall undertake a short-term, high-intensity monitoring program for the parameter(s). Samples identical to those required for routine 

monitoring purposes shall be taken on each of at least three consecutive operating and discharging days and analyzed. Results shall be expressed in terms 

of both concentration and mass, and shall be submitted no later than the end of the third month following the month when the additional monitoring 

requirement was triggered. Results may be appended to the DMR or transmitted under separate cover to the same address. Iflevels higher than the Action 

Levels are confirmed, the permit may be reopened by the Department for consideration of revised Action Levels or effluent limits. The permittee is not 

authorized to discharge any of the listed parameters at levels which may cause or contribute to a violation of water quality standards. TYPE I : The 

additional monitoring requirement is triggered upon receipt by the permittee of any monitoring results in excess of the stated Action LeveL TYPE II: 

The additional monitoring requirement is triggered upon receipt by the permittee of any monitoring res~lts that show the stated action level exceeded for 

four of six consecutive samples, or for two of six consecutive samples by 20 % or more, or for any one sample by 50 % or more. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 3 of 28 

· PERMIT LIMITS, LEVELS AND MONITORING 

C:\MvF11esl0000132o.07mod.sm.wod 

OUTFALL NUMBER WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRING II 

001 Noncontact cooling water (electrical system), St. Lawrence River 06/01104 05/31109 

stormwater runoff, mechanical pump gland 

seal water, and outfall 01A. 

ETER MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES (FN) 

pH 6.0 9.0 su Weekly Grab 

Temperature Monitor A 90 oF Weekly Grab 

EFFLUENT LIMIT PQL MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. Daily Max. TYPE I TYPE II 

'Flow Monitor Monitor MGD Conti Recorder 

Total Dissolved Solids Monitor Monitor mg/1 Weekly 24hr.comp. 

Total Suspended Solids Monitor 20 mg/1 Weekly 24hr.comp. 

Oil & Grease Monitor 10 g Once/2 weeks Grab 

Foam (visible) None None Weekly Grab 1 

Aluminum, Total 4.6 i 7.5 lbs/day Weekly 24hr.comp. 2 

Arsenic, Total . . 0.30 lbs/day Quarterly 24hr.comp. 

Chlorine, Total Residual Monitor 1000 ug/1 Monthly Grab 

Copper, Total - - 0.35 lbs/day Quarterly 24hr.comp. 3 

Cyanide, Total 0.57 1.2 lbs/day Once/2 weeks 24hr.comp. 2 

80 200 ug/1 

Fluoride, Total 140 210 lbs/day Weekly 24hr.comp. 2 

20,000 30,000 ug/1 

Nickel, Total 0.38 0.56 lbs/day Monthly 24hr.comp. II 

Phosphorus, Total Monitor I Monitor lbs/day Quarterly 24hr.comp. 

Selenium, Total . 0.20 lbs/day Quarterly 24hr.comp. 

Tin, Total 0.25 0.43 lbs/day Quarterly 24hr.comp. 

Zinc, Total Monitor 1.1 lbs/day Monthly 24hr.comp. 

P AHs, Individual Monitor 10 ug/1 Once/2 weeks 24hr.comp. 4 

Aroclor 1242 Monitor 0.001 300 ng/1 Weekly Grab 

Aroclor 1248 Monitor 0.001 300 ng/1 Weekly Grab HAroclor 1254 Monitor 0.001 300 ng/1 Weekly Grab 5 

Aroclor 1260 Monitor 0.001 300 ngll Weekly Grab 5 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 4 of 28 

PERMIT LIMITS, LEVELS AND MONITORING 

C:IMyFI!es\0000132p.07mod.sm.wpd 

OUTFALL WASTEWATER TYPE RECEIVING EFFECTIVE EXPIRING 

NUMBER WATER 

OIA Potline S02 W APC bleed stream, contaminated gw from North Yard, 001 06/01/04 05/31109 

stormwater runoff, water intake filter backwash, dewatering bed filtrate, direct 

steam sparging, washdown waters, pitch pump house sump & steam condensate, 

No. 6 fuel oil & pitch secondary containment area stormwater, misc. process 

wastewaters, and outfalls 0 I B & 01 C. 

PARAMETER T MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES 

pH I 6.0 9.0 su 2/Week Grab 

EFFLUENT LIMIT PQL MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly A vg. Daily Max. Daily Max. TYPE I TYPE II 

Flow Monitor 220,000 GPD Continuous Recorder 

WAPCFiow Monitor Monitor GPD Daily Totalizer 

CBOD5 - - 20 mg/1 Monthly 24hr.comp. 

jTKN Monitor 20 mg/1 Monthly 24hr.comp. 

Total Dissolved Solids Monitor Monitor mg/1 Once/2 weeks 24hr.cornp. 

Total Suspended Solids Monitor 20 mg/1 Once/2 weeks 24hr.cornp. 

Oil & Grease Monitor 10 mg/1 Mon G~ Foam (visible) - - None visible Weekly Grab 6 

Aluminum, Total 2.8 6.3 lbs/day Once/2 weeks 24hr.comp. 

Antimony, Total 0.85 1.9 lbs/day Quarterly 24hr.comp. 

Fluoride, Total 29 63 lbs/day Once/2 weeks 24hr.comp. 

Benzo(a)pyrene 0.016 0.033 lbs/day Once/2 weeks 24hr.comp. 

P AHs, Individual 1 Monitor 10 ug/1 Once/2 weeks 24hr.cornp. 4 

Phenols, Total - - 50 ug/1 Monthly 24hr.comp. 

Aroclor 1242 Monitor 0.001 300 ng/1 1 Weekly Grab 5 

Aroclor 1248 Monitor 0.001 300 1 ng/1 Weekly Grab 5 

Aroclor 1254 Monitor 0.001 300 ng/1 Weekly Grab 5 

Aroclor 1260 Monitor 0.001 300 ng/1 Weekly Grab 5 

Production Rate (Potroom) Monitor - M#/d Monthly Calculated 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 5 of 28 

C:\MyFIIes\0000132p.07rnod.sm.wpd 

PERMIT LIMITS, LEVELS AND MONITORING 

OUTFALL No. WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRING 

018 Black Mud Pond groundwater. Outfall OIA 06/01104 05/31109 

PARAMETER MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES 

pH Monitor Monitor su Monthly Grab 

ENFORCEABLE LIMIT MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. TYPE I TYPE II I 

Flow Monitor 13,000 GPD Continuous Recorder 

TKN Monitor 20 mg/1 Monthly 4 hr.comp. II 

Cyanide, Total Monitor 1100 ug/1 Once/2 weeks 4hr.comp. I 

I 

OUTFALL No. WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRING 

OIC Landfill groundwater. Outfall OIA 06/01/04 05/31/09 

ENFORCEABLE LIMIT MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. TYPE I TYPE II 

Flow Monitor Monitor GPD Weekly Totalizer 7 

TKN " - 40 mg/1 Monthly Grab 7 

Cyanide, Total - " 2200 ug!l Once/2 weeks Grab 7 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 6 of 28 

· PERMIT LIMITS, LEVELS AND MONITORING 

002 

PARAMETER 

pH 

Temperature 

PARAMETER 

Flow 

Total Dissolved Solids 

Total Suspended Solids 

Oil & Grease 

Foam (visible) 

Aluminum, Total 

Antimony, Total 

Chlorine, Total Residual 

Fluoride, Total 

Nickel, Total 

Phosphorus, Total 

Zinc, Total 

P AHs, Individual 

Phenols, Total 

Aroclor 1242 

Aroclor 1248 

Aroclor 1254 

Aroclor 1260 

Production Rate (DCC) 

WASTEWATER TYPE 

Direct chill contact cooling water, noncontact 

cooling water (compressors and air 

conditioning), stormwater runoff, boiler 

blowdown, steam condensate, and water tower 

overflow. 

MINIMUM MAXIMUM UNITS 

6.0 9.0 su 

Monitor Average 90 oF 

EFFLUENT UMIT PQL 

Monthly Avg. Daily Max. Daily Max. 

Monitor Monitor 

Monitor Monitor 

Monitor 20 

Monitor 1 14 

None None 

Monitor 6.0 

0.60 1.3 

Monitor 1000 

18 42 

0.25 0.38 

Monitor Monitor 

Monitor 1.0 

Monitor 6.0 

. 

Monitor 0.001 300 

Monitor 0.001 300 

Monitor 0.001 300 

Monitor 0.001 300 

Monitor -

RECEIVING WATER EFFECTIVE EXPIRING 

St. Lawrence River 06/01104 05/31/09 

SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES (FN) 

Weekly Grab 

Weekly Grab 

MONITORING 

ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

TYPE I TYPE II 

MGD Continuous Recorder 

mg/1 Weekly Grab 

lbs/day Weekly Grab 12 

lbs/day Weekly Grab 12 

visible Weekly Grab I 

lbs/day Weekly 24hr.comp. 12 

lbs/day Quarterly 24hr.comp. 

ug/1 Once/2 weeks Grab 

lbs/day Monthly 24hr.comp. 

lbs/day Quarterly 24hr.comp. 

lbs/day Quarterly 24hr.comp. 

lbs/day Monthly 24hr.comp. 

ug/1 I Monthly 24hr.c 

50 ug/1 Monthly 24hr.comp . 

ng/1 Weekly Grab 5 

ng/1 Weekly Grab 5 

ng/1 Weekly Grab 5 

ng/1 Weekly Grab 5 

M#/d Monthly Calculated 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 7 of 28 

· PERMIT LIMITS, LEVELS AND MONITORING C:\MvFiles\0000132o.07mcd.sm.wPd 

OUTFALL NUMBER WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRING 

003 Sewage, oil/water separator effluent (steam St. Lawrence River 06/01/04 05/31/09 

cleaning wastewaters), laboratory floor 

drains, east sump groundwater, and 

miscellaneous process wastewaters. 

PARAMETER MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES (FN) 

IPH 6.0 9.0 su 2/Week Grab 

EFFLUENT LIMIT PQL MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. Daily Max. TYPE I TYPE II 

Flow Monitor 0.22 MGD Continuous Recorder 

CBOD5 25 40 mg/1 Monthly 24hr.comp. 

TKN Monitor 20 mg/1 Monthly 24hr.comp. 

Total Dissolved Solids I Monitor Monitor 1 mg/1 Once/2 weeks 24hr.comp. 

Total Suspended Solids Monitor 20 I mg/1 Once/2 weeks 24hr.comp. 

Oil & Grease Monitor 10 mg/1 Monthly Grab 

Foam (visible) None None visible Weekly Grab 1 

Fecal Coliform 200 (30 day geometric mean) MPN/100 m1 Monthly Grab 

400 ( 7 day geometric mean) 

Aluminum, Total 2000 4000 ug/1 Once/2 weeks 24hr.comp. 

Chlorine, Total Residual Monitor 2000 ug/1 2/week Grab 

Cyanide, Total 80 200 ug/1 Once/2 weeks 24hr.comp. 

Fluoride, Total 20,000 30,000 ug/1 Once/2 weeks 24hr.comp. 

Phosphorus, Total Monitor Monitor ug/1 Quarterly 24hr.comp. 

Zinc, Total - - 200 ug/1 Quarterly 24hr.comp. 

P AHs, Individual Monitor 10 ug/1 Monthly 24hr.comp. 4 

Phenols, Total - - 50 ug/1 Once/2 weeks 24hr.comp. 8 

Aroclor 1242 Monitor 0.001 300 ng/1 Weekly Grab 5 

Aroclor 1248 Monitor 0.001 300 ng/1 Weekly Grab 5 

Aroclor 1254 Monitor 0.001 300 ng/l Weekly Grab 5 

Aroclor 1260 Monitor 0.001 300 ng/1 Weekly Grab 5 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 8 of 28 

- PERMIT LIMITS, LEVELS AND MONITORING 

OUTFALL NUMBER WASTEWATER TYPE EXPIRING 

005 Stormwater runoff and vehicle rinse 05/31/09 

PARAMETER MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES (FN) 

pH 6.0 9.0 su Weekly Grab 

Settleable Solids Monitor Average 0.1 mVI 

EFFLUENT LIMIT PQL MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. Daily Max. TYPE I TYPE II 

Flow Monitor Monitor GPD Weekly Instantane:ous 

Total Dissolved Solids Monitor Monitor j mg/1 Monthly Grab 

Total Suspended Solids " " 40 mg/1 Monthly Grab 

Oil &Grease Monitor 10 mg/1 Monthly Grab 

.. - - None visible Weekly Grab 6 

I~ ~ 2000 4000 ug/1 Quarterly Grab 

Fluoride, Total 20,000 30,000 ug/1 Quarterly Grab 

P AHs, Individual Monitor 10 ug/1 Quarterly Grab 4 

Aroclor 1242 Monitor 0.001 300 ng/1 Once/2 weeks Grab 5 

Aroclor 1248 Monitor 0.001 300 ng/1 Once/2 weeks Grab 5 

Aroclor 1254 Monitor 0.001 300 ng/1 eks Grab 

Aroclor 1260 Monitor 0.001 300 ng/1 Once/2 weeks Grab ~ 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 9 of 28 

· PERMIT LIMITS, LEVELS AND MONITORING 

C:IMyFiles\0000132o.07mod.sm.wod 

OUTFALL NUMBER WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRING 

008 Stormwater runoff. St. Lawrence River 06/01/04 05/31/09 

PARAMETER MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES (FN) 

pH 6.0 9.0 su Weekly Grab 

Settleable Solids Monitor Average 0.1 mill Weekly Grab 

EFFLUENT LIMIT QL MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly A vg. Daily Max. Daily Max. TYPE I TYPE II 

I~ Monitor Monitor GPD Weekly Instantaneous 

Total Dissolved Solids Monitor Monitor mg/1 Monthly Grab I 

Total Suspended Solids - - 40 mg/1 Monthly Grab 

Oil & Grease Monitor 10 mg/1 ly Grab 

Foam (visible) - - N visible Weekly Grab 6 

Aluminum, Total 2000 4000 ug/1 Quarterly Grab 

Cyanide, Total 80 200 ug/1 Once/2 weeks Grab 9 

Fluoride, Total 20,000 30,000 ug/1 Once/2 weeks Grab 9 

P AHs, Individual Monitor 10 ug/1 Quarterly Grab 4 

Aroclor 1242 Monitor 0.001 300 ng/1 Monthly Grab 5 

Aroclor 1248 Monitor 0.001 300 ng/1 Monthly Grab 

~I Aroclor 1254 Monitor 0.001 300 . ng/1 Monthly Grab 

Aroclor 1260 Monitor 0.001 300 ng/1 Monthly Grab 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 10 of 28 

· PERMIT LIMITS, LEVELS AND MONITORING 

C:\Myfiles\0000132p,07mod.sm,wp<l 

II OUTFALL NUMBER WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRING 

II 010 Stormwater runoff, vehicle rinse water, and Raquette River 06/01/04 05131109 

noncontact cooling water (rectifier yard). 

PARAMETER MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES (FN) 

pH 6.0 9.0 su Weekly Grab 

Settleable Solids Monitor Average 0.1 ml/1 Weekly Grab 

EFFLUENT LIMIT PQL MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. Daily Max. TYPE I TYPE II. 

Flow Monitor Monitor GPD Weekly Instantaneous 

Total Dissolved Solids Monitor Monitor mg/l Monthly Grab 

Total Suspended Solids - 40 mgll Monthly Grab 

Oil & Grease Monitor 10 mgll Monthly Grab 

Foam (visible) - None visible Weekly Grab 6 

Aluminum, Total 2000 4000 ugll Monthly Grab 

Cyanide, Total 80 200 ugll Once/2 weeks Grab 10 

Fluoride, Total Monthly 10,000 ug/1 Quarterly Grab 

PARs, Individual Monitor 10 ugll Quarterly Grab 4 

Aroclor 1242 Monitor 0.001 300 ng/1 Monthly Grab 5 

Aroclor 1248 Monitor 0.001 300 ng/1 Monthly Grab 5 

Aroclor 1254 Monitor 0.001 300 ngll Monthly Grab 5 

Aroclor 1260 Monitor 0.001 300 ng/1 Monthly Grab 5 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 11 of 28 

PERMIT LIMITS, LEVELS AND MONITORING 

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OUTFALL NUMBER WASTEWATER TYPE RECEIVING WATER EFFECTIVE EXPIRIN 

011 Stormwater runoff and groundwater. R;aguette River 06/01104 05/31/09 

PARAMETER MINIMUM MAXIMUM UNITS SAMPLE FREQUENCY SAMPLE TYPE FOOTNOTES (FN) 

pH 6.0 9.0 su Quarterly Grab 

Settleable Solids Monitor Average 0.1 ml/1 Quarterly Grab 

EFFLUENT LIMIT PQL MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. Dai1yMax. TYPE I TYPE II 

Flow Monitor Monitor GPD Quarterly Instantaneous 

Total Dissolved Solids Monitor Monitor mg/1 Quarterly Grab 

Total Suspended Solids - - 40 mg/1 Quarterly Grab 

Oil & Grease Monitor 10 mg/1 Quarterly Grab 

Foam (visible) - - None visible Quarterly Grab 6 

Aluminum, Total 2000 4000 . ug/1 Quarterly Grab 

Cyanide, Total Monitor 60 ug/1 Quarterly Grab 

Fluoride, Total Monitor 10,000 ug/1 Quarterly Grab 

Iron, Total Monitor Monitor ug/1 Quarterly Grab 

P AHs, Individual Monitor 10 ug/1 Quarterly Grab 4 

Aroclor 1242 Monitor 0.001 300 ng/1 Quarterly Grab 5 

Aroclor 1248 Monitor 0.001 300 ng/1 Quarterly Grab 5 

Aroclor 1254 Monitor 0.001 300 ng/1 Quarterly Grab 5 

Aroclor 1260 Monitor 0.001 300 ng/1 Quarterly Grab 5 
SPDES PERMIT NUMBER NYOOOOI32 

Part I, Page 12 of 28 

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PERMIT LIMITS, LEVELS AND MONITORING 

OUTFALL NUMBER RECEIVING WATER EFFECfiVE EXP1RING 

Sum ofOutfalls 001, 002, 003, 005, 008, 010, and/or 01 L St. Lawrence River 06/01/04 05/31/09 

ENFORCEABLE LIMIT MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly Avg. Daily Max. TYPE I TYPE II 

Benzo( a )anthracene 33 Monitor grams/d Monthly Calculated 11 

Benzo( a )pyrene 20 Monitor grams/d Monthly Calculated 11 

Benzo(b )fluoranthene 33 Monitor grarns/d Monthly Calculated 11 

Benzo(k)fluoranthene 33 Monitor grams/d Monthly Calculated 

"""''· 33 Monitor grams/d Monthly Calculated 

IL 3-cd)pyrene 33 Monitor grams/d Monthly Calc~GJ 

OUTFALL NUMBER RECEIVING WATER EFFECTIVE EXPIRING 

Sum of Outfalls 0 10 and 011. Raquette River 06/01/04 05/31109 

ENFORCEABLE LIMIT MONITORING 

PARAMETER ACTION LEVEL SAMPLE SAMPLE FN 

UNITS FREQUENCY TYPE 

Monthly A vg. Daily~ TYPE II 

Benzo(a)pyrene 1.5 M' Calculated II 
SPECIAL CONDITIONS and DEFINITIONS: 

SPDES PERMIT NUMBER NY0000132 

Part I, Page 13 of 28 

The following special conditions and definitions apply to all activities regulated by this permit .. 

A. Reporting Mass and Concentration- The permittee must report both concentration (in mg/1 for conventionals; in ug/1 for metals, 

inorganics, and organics; in ng/1 for PCBs and specific P AHs) and mass loading (in lbs/day for all but PCBs and P AHs which shall 

be in grams/day) on the DMRs for all parameters except flow, pH, temperature, settleable solids, foam, and fecal coliform. 

B. Composite Samples - All 24 hour composite samples ml!st be flow proportional. All 4 hour composite samples must be time 

proportional. 

C. Analytical Methods- Use of the following analytical methods, or other approved analytical methods that are equally or more 

sensitive, is required. This is necessary in order to ensure adequate detection limits and compliance with permit limits. Less 

sensitive analytical methods may be utilized, and the results compared to permit limits to make compliance determinations. 

However, these less sensitive methods may not be substituted to satisfy routine of other permit-specified monitoring requirements. 

• Cyanide, Total- EPA method 335.2, PQL 60 ug/1 or less. 

• Antimony, Arsenic, Nickel, and Tin - GFAA, PQL 10, 4, 4, and 20 ug/1 or less, respectively. 

• Selenium- GFAA or FAA, PQL 8 ug/1 or less. 

• Zinc- GFAA or ICP, PQL 8 ug/1 or less. 

• PAHs- EPA method 610 (GCIHPLC). 

• Phenols, Total- EPA method 420.2, PQL 8 ug/1 or less. 

• PCB Aroclors- EPA method 608 (GCIECD). The laboratory must make all reasonable attempts to achieve a MDL of 

65 ng/1 or less per Aroclor. Monitoring requirements may be modified in the future, in accordance with 6NYCRR Part 

621, if the Department approves a method different from 608. See footnote 5. 

• Visible Foam 

1) Fill one (1) 500 mL narrow mouth bottle (glass or plastic) with effluent water to be tested. 

2) Upon return to the lab, fill alOOO mL Wheaton narrow mouth glass sample bottle to the 200 mL mark with 

effluent from the 500 mL bottle. 

3) Place the bottle with 200 mL of sample in a constant-temperature bath for a minimum of 1 hour and a rna:runum 

of 2 hours at 25 ± 1 °C (77 ± 1.8°F). 

4) Measure the temperature of the sample and adjust to 25 ± 1 °C (77 ± 1.8°F) if necessary. 

5) Remove the sample from the constant-temperature bath. 

6) Vigorously shake the sample bottle using a minimum of an 8-inch stroke and 40 shakes in less than l 0 seconds. 

7) After completing 40 shakes, start a timer and allow the bottle to stand undisturbed. 

8) If any foam remains after 60 seconds, the sample will be noted as containing visible foam. If no foam remains 

after 60 seconds the sample will be noted as not containing visible foam. 

D. Flow Monitoring: 

Continuous Recorder - A flow measurement system that continuously measures and displays the instantaneous flow rate, and 

cumulative discharge volume, versus time on paper and/or electronically. 

Totalizer A flow measurement system that contiuuously measures and displays the instantaneous flow rate and records the 

cumulative discharge volume on a mechanical meter. 

E. Approvable is defmed as that which can be approved by the Department with only minimal revision. Minimal revision shall mean 

revised and resubmitted to the Department within 30 days of notification by the Department of revisions that are necessary. All 

approvable engineering submissions must include the seal and signature of an engineer licensed to practice in New York State. 

F. Electronic Reporting Within 90 days following the end of each calendar year, the permittee shall submit, to the Regional Water 

Engineer, and the Bureau of Water Permits, accurate summary table(s) including each analytical result for samples collected 

during the previous year. The table shall include daily flow rates (if required by the permit) and the individual sample results in 

both concentration and mass where appropriate. The tables shall be submitted on a personal computer diskette in a spreadsheet 

format acceptable to the Department. This reporting is for informational purposes only and will not be used to determine 

compliance with permit requirements. 
SPECIAL CONDITIONS and DEFINITIONS {continued): 

SPDES PERMIT NUMBER NY0000132 

Part I, Page 14 of 28 

G. Miscellaneous Wastewater Treatment - The Miscellaneous Wastewater Treatment Plan, when approved, shall become an 

enforceable compliance requirement of this SPDES permit. 

H. Stormwater Only Outfalls Monitoring Threshold- Monitoring ofoutfalls 005,008,010, and 011 is not required if the outfall's 

flow rate is less than 5 gpm. However, any monitoring performed at flow rates less than 5 gpm will be used to determine permit 

compliance and must be reported on the DMR. 

F001NOTES: 

The following footnotes apply to certain activities as noted on the previous permit pages. 

1. If foam is observed in accordance with Special Condition C then the permit limit has been exceeded. 

2. Interim requirements are in effect at outfall 001 until December 31, 2005, as follows: aluminum limits of 4.6/22 #I d, cyanide limits 

ofO. 5 7/1.2 lbs/ day and no concentration limits; fluoride limits of140/360 lbs/ day and no concentration limits; and, tin mon:itoring 

with no limits. 

3. Copper monitoring at outfall 001 shall be daily during the first two discharge days following algaecide application. 

4. Each individual Polynuclear Aromatic Hydrocarbon (P AH) detected by EPA method 610 shall be at or below 10 ug/1 ( 6.0 ug/1 

at outfall 002) in order to demonstrate compliance with this limitation. P AHs specifically identified for limitation at the outfall 

are excepted from this requirement. Analytical results shall be summarized and appended to the DMR. For compliance pmposes, 

if one or more P AHs exceed the permitted level for a sampling event it will constitute one permit limit exceedance. 

5 .a. lfPCBs are detected above the Minimum Detection Level (MDL), the permittee shall provide a written detection report attached 

to the DMR. The written detection report shall contain a description of the detection and its known or probable cause; including 

exact dates and if the detection has not been corrected, the anticipated time it is expected to continue; and short term steps taken 

or planned to reduce , eliminate and prevent the detection and its reoccurrence. 

5.b. Non-detect at the MDL or lower is the discharge goal. As outlined in 5a, the permittee shall report all values above the MDL. 

If the level of any aroclor is above 65 ng/1, the permittee must evaluate the treatment system and/or the wastewater source to 

identify the cause of the detectable level ofPCBs in the discharge. Following three consecutive months that include analytical 

results above 65 ng/1, the permittee shall prepare an approvable report identifying the long term measures undertaken to reduce, 

eliminate and prevent the detections and proposed additional steps, if necessary and feasible (both technically and economically), 

to be taken to reduce, eliminate or prevent the recurrence of such detections. This report shall be submitted to the Department 

within 60 days following receipt of sampling results from the third detection monitoring period. 

5.c. If the Department determines that effluent monitoring results above the MDL can be reduced, eliminated or prevented by 

implementation of additional technically and economically feasible measures as proposed by the permittee in 5b, the permittee 

shall implement such additional measures. 

S.d. As treatment technology improvements become available, the permittee shall, at its own initiative or the Department's n~quest, 

review the available technology and submit for Department approval, plans to improve the treatment technology and/or Best 

Management Practices employed to remove the maximum feasible amount of PCBs from the wastewater discharge. 

5.e. This limit is a phased Total Maximum Daily Load limit, prepared in accordance with 6 NYCRR Part 702.16(b). 

5.f. Modification of requirements for use of analytical procedures (Special Condition C) and requirements for use of improved 

treatment technologies as such improved technologies become available (5d) will be implemented as a permit modification in 

accordance with 6 NYCRR Part 621. 
FOOTNOTES (continued): 

SPDES PERMIT NUMBER NY0000132 

Part I, Page 15 of 28 

6. If foam is observed the action level has been exceeded and one duplicate sample must then be analyzed for MBAS. Performance 

of the three day monitoring program is only required if the MBAS result exceeds 400 ug/1. 

7. Outfall 01 C requirements will remain in effect until ExDP. However, there is a treatability threshold. For the purposesof this 

permit, exceedance of the treatability threshold is defmed as either of the following events - three consecutive sample results 

exceed the action level for a parameter or five of the last eight sample results exceed the action level for a parameter. 

If the treatability threshold is exceeded, within 30 days following such exceedance the permittee shall connect up to 10,000 gpd 

of landfill wastewater to the OlB treatment system or send this volume off-site for treatment. If the quantity of wastewater 

requiring treatment exceeds the capacity of the 0 lB treatment system the system shall be expanded as necessary to treat the 

remainder of this wastewater or this excess volume must be sent off-site for treatment. If off-site treatment of this excess volume 

is selected, this opemtion must commence within 60 days. If on-site treatment of this excess volume is selected, the permittee 

has 9 months to propose, receive Department approval of, and construct a system which will achieve fmallimits. 

Once treatment is started, if three consecutive sample results do not exceed the outfall 0 lB pollutant limits or five of the last eight 

sample results do not exceed the outfall 0 lB pollutant limits, then the water may be returned to its originally permitted flow path. 

8. Interim requirements are in effect at outfall 003 until 06/01/2007, as follows: phenols monitoring with no limits. 

9. Interim requirements are in effect at outfall 008 until 06/01/07, as follows: cyanide limits of 1300/2700 ug/1 avg/max, and a 

fluoride limit of 60,000 ug/1 daily average. 

10. Interim requirements are in effect at outfall 010 until 06/01/07, as follows: cyanide limits of350/1100 ug/1 avg/max. 

11. Each month, the P AH results shall be averaged for each outfall. These average outfall values must then be summed and compared 

to the "sum of outfalls" limits to determine compliance. During months when an outfall does not discharge or monitoring is not 

performed, that outfall does not contribute anything to the sum. 

12. Interim requirements are in effect at outfall 002 until 06/01/10, as follows: TSS limits of20/40 mg/1 avg/max, a oil & grease limit 

of 15 mg/1, and an aluminum limit of 12lbs/day. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 16 of 28 

TOXICITY TESTING PROGRAM, TIER 1 -ACUTE TEST 

The Department has dete:rrn:ined that an acute effluent toxicity monitoring program is required. The permittee shall implement the 

program as follows: 

Effluent Toxicity Monitoring Requirements 

Outfall Effluent Reason for Testing Requirement Sample Frequency Sample 

No. Parameters Type 

(Unitsl 

Sum of Toxicity The presence of substances for which ambient Quarterly Flow001, 002, (% water quality criteria do not exist. Uncertainties in weighted 

003,005, Effluent) the development ofTMDLs, WLAs, WQBELs, During calendar years ending in composite 

008,010, etc. The presence of substances for which [6] and [1] of outfalls* 

&011 WQBELs are below analytical detectability. 

The possibility of complex or synergistic 

interactions of chemicals. .. A The effluent toxicity monitoring program shall begm m January of the years noted m the table above. Subsequent modif1cat10n 

or renewal of this permit does not reset or revise the deadline(s)set forth in the preceding sentence unless a new deadline is set 

explicitly by such modification or renewal. 

B. The results of each toxicity test shall be submitted no later than 60 days following the end of each test period. These reports shall 

be submitted to the NYS DEC Regional Water Engineer at Region 6, State Office Building, 317 Washington Street, W ate:rtown, 

NY 13 601-3 787; and to the Toxicity Testing Unit, Bureau of Watershed Assessment and Research, 625 Broadway, Albany, NY 

12233-3502. 

C. Effluent Toxicity shall mean the toxicity of the effluent in acute static renewal tests specified as Tier 1 testing in Methods for 

Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition, 

EPA/600/4-90/027F (1993) or most recent edition (herein referred to as the EPA Acute Manual). Both a vertebrate and 

invertebrate species shall be used for the tests. Where the outfall being tested discharges to estuarine or ocean waters, the marine 

organisms shall be tested. Where the outfall being tested discharges to fresh waters, freshwater organisms shall be tested. Dilution 

water shall be collected according to the EPA Acute Manual. Receiving water shall be used as dilution water unless the 

Department approves a different source. Effluent sampling and holding shall be done as outlined in the EPA Acute Manual, and 

should also be consistent with outfall-specific requirements. Any deviation from procedures in the EPA Acute Manual r<~quires 

prior written approval by the Department. 

D. The· 48-hour EC50 and 48-hour LC50 in % Effluent for both a vertebrate and an invertebrate species shall be dete:rrn:ined and 

reported in accordance with the specified frequency. The 48-hour EC50 and 48-hour LC50 in% Effluent shall be compared to the 

Instream Waste Concentration (IWC) of the effluent calculated based on the daily average effluent flow at the time of the test and 

the critical flow in the St. Lawrence River of 38300 MGD. 

E. Where practicable, monitoring of chemical and physical parameters limited in this permit shall be coordinated so that the re:sulting 

analysis is also representative of the sample used for toxicity testing. 

F. Discharges which use chlorination as part of the waste treatment process for disinfection should be dechlorinated prior to toxicity 

testing or samples shall be taken immediately prior to the chlorination system 

G. In accordance with NYSDEC guidance, the Department may require the permittee to conduct additional toxicity testing. If such 

additional testing is necessary, the permittee shall be notified in writing by the NYS DEC Regional Water Engineer. The written 

notification shall include the reason(s) why such testing is required. 

* -The flow-weighted composite shall be based on 24 hour composite samples taken from outfalls 001, 002, and 003, and, grab samples 

taken from outfalls 005, 008, 010, and 011. 
Outfall 

No. 

Sum of 

001,002, 

003,005, 

008,010, 

& 011 

SPDES PERMIT NUMBER NY0000132 

Part I, Page 17 of 28 

TOXICITY TESTING PROGRAM, TIER 2 -CHRONIC TEST 

Effluent Toxicity Monitoring Requirements 

Effluent Reason for Testing Requirement Sample Frequency Sample 

Parameters Type 

(Units) 

Toxicity The presence of substances for which ambient As directed by the Regional Water Flow-

(% water quality criteria do not exist. Uncertainties in Engineer weighted 

Effluent) the development ofTMDLs, WLAs, WQBELs, composite 

etc. The presence of substances for which of outfalls* 

WQBELs are below analytical detectability. 

The possibility of complex or synergistic 

interactions of chemicals. 

A. The permittee shall implement this effluent toxicity monitoring program beginning in the first month of the first full calendar 

quarter, i.e. January, April, July, or October, that is within 3 months of written notification from the NYSDEC Regional Water 

Engineer that chronic toxicity testing is necessary. The written notification will include the reasons why the chronic toxicity testing 

program is necessary and the sample frequency. 

B. The results of each toxicity test shall be submitted no later than 60 days following the end of each test period. These reports shall 

be submitted to the NYS DEC Regional Water Engineer at Region 6, State Office Building, 317 Washington Street, Watertown, 

NY 13601-3787; and to the Toxicity Testing Unit, Bureau ofWatershedAssessment and Research, 625 Broadway, Albany, NY 

12233-3502. 

C. Effluent toxicity shall mean the toxicity of the effluent in chronic static renewal tests as specified in Short-Term Methods for 

Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, Third Edition, EP A/600/4-91/002 

(1994), the EPA Chronic Manual for Marine Organisms (EPA/600/4-91/003(1994), or the most recent editions (herein referred 

to as the EPA Chronic Manuals). Both a vertebrate and invertebrate species shall be used for the tests. Where the outfaH being 

tested discharges to estuarine or ocean waters, marine organisms shall be tested. Where the outfall being tested discharges to fresh 

waters, freshwater organisms shall be tested. Each test run shall be 'bracketed' with a test of pure effluent and a test of effluent 

diluted sufficiently such that at least one diluted sample shows no toxic effects. Appropriate dilutions between the endpoints shall 

be tested to allow calculation of the Maximum Allowable Waste Concentration. Dilution water shall be collected according to 

the EPA Chronic Manuals. Receiving water shall be used as dilution water unless the Department approves a different source. 

Effluent sampling and holding shall be done as outlined in of the EPA Chronic Manuals. Any deviation from procedures in the 

EPA Chronic Manuals requires prior written approval by the Department. 

D. The Maximum Allowable Waste Concentration (MA WC) in% Effluent, for both a vertebrate and an invertebrate species, shall 

be determined and reported. The MA WC in% Effluent shall be compared to the calculated Instream Waste Concentration (IWC) 

of the effluent. The IWC in % Effluent shall be determined using the daily average effluent flow at the time of sampling and a 

critical receiving water flow in the St. Lawrence River of 38300 MGD. 

E. Where practicable, monitoring of chemical and physical parameters limited in this permit shall be coordinated so that the resulting 

analysis is also representative ofthe samples used for toxicity testing. 

F. Discharges which use chlorination as part of the waste treatment process for disinfection should be dechlorinated prior to toxicity 

testing or samples shall be taken immediately prior to the chlorination system. 

G. In accordance with NYSDEC guidance, the Department may require the permittee to conduct additional toxicity testing. If such 

additional testing is necessary, the permittee shall be notified in writing by the NYS DEC Regional Water Engineer. The written 

notification shall include the reason( s) why such testing is required. 

*-The flow-weighted composite shall be based on 24 hour composite samples taken from outfalls 001, 002, and 003, and, grab samples 

taken from outfalls 005, 008, 010, and 011. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 18 of 28 

TOXICITY REDUCTION EVALUATION COMPLIANCE SCHEDULE 

(a) In accordance with Department guidance on whole effluent toxicity monitoring and control, the Department will evaluate the 

results of acute and/or chronic toxicity testing of discharges authorized by this permit. Based on this evaluation, the Department 

may require the permittee to perform a Toxicity Reduction Evaluation (TRE). Should a TRE be required, the permittee shall be 

notified in writing by the NYS DEC Regional Water Engineer. The written notification shall include the reasons why the TRE 

is required. 

(b) Within 60 days of the date of the written notification from the NYS DEC Regional Water Engineer in (a), the permittee shall 

submit an approvable proposal for Toxicity Reduction Evaluation to the Bureau of Watershed Assessment and Research, 625 

Broadway , Albany, NY 12233-3502. The TRE proposal shall be directed towards identifying the source of the toxicity, 

describing procedures to reduce the toxicity to an acceptable level, identifying monitoring parameters suitable for insuring control 

of the toxicity, and proposing a schedule for completing the TRE. 

(c) Within 14 days of receipt of written approval of the TRE proposal from the DEC Regional Water Engineer, the permittee shall 

implement the approved TRE proposal in accordance with the approved schedule. 

(d) The completed TRE, including data fmdings and recommendations for corrective action, permit limits, and proposed self~ 

monitoring requirements shall be submitted to the Bureau ofWatershed Assessment and Research at the address noted in (b) on 

this page. The Department will review the TRE and may modify the permit, in accordance with applicable law & regulation, to 

incorporate one or more of the following: substance specific numerical limits, toxicity limits, monitoring requirements, and/or 

a schedule of compliance that will ensure acceptable toxicity levels of the effluent. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 19 of 28 

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SPECIAL CONDITIONS- BEST MANAGEMENT PRACTICES 

1. The permittee shall develop a Best Management Practices (BMP) plan to prevent, or minimize the potential for, release of 

significant amounts of toxic or hazardous pollutants to the waters of the State through plant site runoff; spillage and leaks; sludge 

or waste disposal; and storm water discharges including, but not limited to, drainage from raw material storage. Completed BMP 

plans shall be submitted by March 01, 2005 to the Regional Water Engineer at the address shown on the Recording, Reporting 

and Additional Monitoring Requirements page. The BMP plan shall be implemented within 6 months of submission, unless a 

different time frame is approved by this Department. 

2. Subsequent modifications to or renewal of this permit does not reset or revise the deadline set forth in (1) above, unless a new 

deadline is set explicitly by such permit modification or renewal. 

3. The permittee shall review all facility components or systems (including material storage areas; in-plant transfer, proc(~ss and 

material handling areas; loading and unloading operations; storm water, erosion, and sediment control measures; process 

emergency control systems; and sludge and waste disposal areas) where toxic or hazardous pollutants are used, manufactured, 

stored or handled to evaluate the potential for the release of significant amounts of such pollutants to the waters of the State. In 

performing such an evaluation, the permittee shall consider such factors as the probability of equipment failure or improper 

operation; cross-contamination of storm water by process materials, settlement of facility air emissions, the effects of natural 

phenomena such as freezing temperatures and precipitation, fires, and the facility's )listory of spills and leaks. For hazardous 

pollutants, the list of reportable quantities as defined in 40 CFR, Part 117 may be used as a guide in determining siglrificant 

amounts of releases. For toxic pollutants, the relative toxicity of the pollutant shall be considered in determining the significance 

of potential releases. · 

The review shall address all substances present at the facility that are listed as toxic pollutants under Section 307 (a )(1) of th•~ Clean 

Water Act or as hazardous pollutants under Section 311 ofthe Act or that are identified as Chemicals of Concern by the Industrial 

Chemical Survey. Of particular concern are Aluminum, Cyanide, Fluoride, PAHs, and PCBs. 

4. Whenever the potential for a significant release oftoxic or hazardous pollutants to State waters is determined to be present, the 

permittee shall identify BMPs that have been established to minimize such potential releases. Where BMPs are inadequate or 

absent, appropriate BMPs shall be established. In selecting appropriate BMPs, the permittee shall consider typical industry 

practices such as spill reporting procedures, risk identification and assessment, employee training, inspections and records, 

preventive maintenance, good housekeeping, materials compatibility and security. In addition, the permittee may consider 

structural measures (such as secondary containment and erosion/sediment control devices and practices) where appropriate. 

5. Development of the BMP plan shall include sampling of waste stream segments for the purpose of toxic "hot spot" identification. 

The economic achievability of effluent limits will not be considered until plant site "hot spot" sources have been identified, 

contained, removed or minimized through the imposition of site specific BMPs or application of internal facility treatment 

technology. For the purposes of this permit condition a "hot spot" is a segment of an industrial facility; including but not limited 

to soil, equipment, material storage areas, sewer lines etc.; which contributes elevated levels of problem pollutants to the 

wastewater and/or storm water collection system of that facility. For the purposes of this definition, problem pollutants are 

substances for which treatment to meet a water quality or technology requirement may, considering the results of waste stream 

segment sampling, be deemed unreasonable. For the purposes of this defmition, an elevated level is a concentration or mass 

loading of the pollutant in question which is sufficiently higher than the concentration of that same pollutant at the compliance 

monitoring location so as to allow for an economically justifiable removal and/or isolation ofthe segment and/or B.A.T. treatment 

of wastewaters emanating from the segment. 

6. The BMP plan shall be documented in narrative form and shall include any necessary plot plans, drawings or maps. Other 

documents already prepared for the facility such as a Safety Manual or a Spill Prevention, Control and Countermeasure (SPCC) 

plan may be used as part of the plan and may be incorporated by reference. USEPA guidance for development of stonn water 

elements of the BMP is available in the September 1992 manual "Storm Water Management for Industrial Activities," USEPA 

Office of Water Publication EPA 832-R-92-006 (available from NTIS, (703)487-4650, order number PB 92235969). A copy 

of the BMP plan shall be maintained at the facility and shall be available to authorized Department representatives upon request. 

As a minimum, the plan shall include the following BMP's: 

a. BMP Committee e. Inspections and Records i. Security 
b. Reporting ofBMP Incidents f. Preventive Maintenance 

c. Risk Identification & Assessment g. Good Housekeeping 

d. Employee Training h. Materials Compatibility 

SPDES PERMIT NUMBER NY0000132 

Part I, Page 20 of 28 

j. Spill prevention & response 

k. Erosion & sediment control 

1. Management of runoff 

7. The BMP plan shall be reviewed annually and shall be modified whenever: (a) changes at the facility materially increase the 

potential for significant releases of toxic or hazardous pollutants, (b) actual releases indicate the plan is inadequate or (c) a letter · 

from the Regional Water Engineer highlights inadequacies in the plan. 

H. Facilities with Petroleum and/or Chemical Bulk Storage (PBS and CBS) Areas: 

Compliance must be maintained with all applicable regulations including those involving releases, registration, handling and 

storage (6NYCRR 595-599) and (6NYCRR 612-614). Stormwater discharges from handling and storage areas should be 

eliminated where practical. 

A. Spill Cleanup -All spilled or leaked substances must be removed from secondary containment systems as quickly as practical 

and in all cases within 24 hours. The containment system must be thoroughly cleaned to remove any residual contamination which 

could cause contamination ofstormwater and the resulting discharge of pollutants to waters of the State. Following spill cleanup 

the affected area must be completely flushed with clean water three times and the water removed after each flushing for proper 

disposal in an on-site or off-site wastewater treatment plant designed to treat and perinitted to discharge such wastewater. 

Alternatively, the permittee may test the first batch of stormwater following the spill cleanup to determine discharge acceptability. 

If the water contains no pollutants it may be discharged. Otherwise it must be disposed of as noted above. See Discharge 

Monitoring below for the list of parameters to be sampled for. 

B. Discharge Operation- Stormwater must be removed before it compromises the required containment system capacity. Each 

discharge may only proceed with the prior approval of the permittee staff person responsible for ensuring SPDES permit 

compliance. Bulk storage secondary containment drainage systems must be locked in a closed position except when the operator 

is in the process of draining accumulated stormwater. Transfer area secondary containment drainage systems must be locked in 

a closed position during all transfers and must not be reopened unless the transfer area is clean of contaminants. Stormwater 

discharges from secondary containment systems should be avoided during periods of precipitation. A logbook shall be maintained 

on-site noting the date, time and personnel supervising each discharge. 

C. Discharge Screening - . Prior to each discharge from a secondary containment system the stormwater must be screened for 

contamination·. All stormwater must be inspected for visible evidence of contamination. Additional screening methods shall be 

developed by the permittee as part ofthe overall BMP Plan, e.g. the use of volatile gas meters to detect the presence of gross levels 

of gasoline or volatile organic compounds. If the screening indicates contamination, the permittee must collect and analyze a 

representative sample •• of the stormwater. If the water contains no pollutants it may be discharged. Otherwise it must either be 

disposed of in an on-site or off-site wastewater treatment plant designed to treat and permitted to discharge such wastewater or 

the Regional Water Engineer can be contacted to determine if it may be discharged without treatment. 

D. Discharge Monitoring- Unless the discharge from any bulk storage containment system outlet is identified in the SPDES 

permit as an outfall with explicit effluent and monitoring requirements, or the water is properly transferred to a treatment system 

in accordance with the approved Miscellaneous Wastewater Treatment Plan or DEC authorization, the permittee shall monitor 

the outlet as follows: 

(i) Bulk Storage Secondary Containment Systems: 

(a) The volume of each discharge from each outlet must be monitored. A representative sample shall be collected of 

the first discharge • following any cleaned up spill or leak. The sample must be analyzed for pH, the substance( s) stored 

within the containment area and any other pollutants the permittee knows or has reason to believe are present ... 

(b) Every fourth discharge • from each outlet must be sampled for pH, the substance( s) stored within the containment area 

and any other pollutants the permittee knows or has reason to believe are presen(•. 

(ii) Transfer Area Secondary Containment Systems: 

The first discharge • following any spill or leak must be sampled for flow, pH, the substance( s) transferred in that area 

and any other pollutants the permittee knows or has reason to believe are present ... 

E. Discharge Reporting Any results of monitoring required above must be submitted to the Department by appending lhem to 

the corresponding discharge monitoring report (DMR). Failure to perform the required discharge monitoring and reporting shall 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 21 of 28 

constitute a violation of the tenns of the SPDES permit. 

F. Prohibited Discharges- In all cases, any discharge which contains a visible sheen, foam, or odor, or may cause or 

contribute to a violation of water quality is prohibited. The following discharges are prohibited unless specifically authorized 

elsewhere in this SPDES permit: spills or leaks, tank bottoms, maintenance wastewaters, wash waters where detergents or other 

chemicals have been used, tank hydrotest and ballast waters, contained fire fighting runoff, frre training water contaminated by 

contact with pollutants or containing foam or frre retardant additives, and, unnecessary discharges of water or wastewater into 

secondary containment systems. An example of a necessary discharge could be the addition of steam to prevent bulk storage 

containment area sump pumps from freezing during cold weather. 

* 

** 

Discharge includes storm water discharges and snow and ice removal. If applicable, a representative sample of snow and/or ice should be collected 

and allowed to melt prior to assessment. 

If the stored substance is gasoline or aviation fuel then sampled for oil & grease, benzene, ethylbenzene, naphthalene, toluene and total xylenes (EPA 

method 602). lf the stored substance is kerosene, diesel fuel, fuel oil or lubricating oil gasoline or aviation fuel then sampled for oil & grease and 

polynuclear aromatic hydrocarbons (EPA method 61 0). If the substance(s) are listed in Tables 6-8 of application form NY-2C sampling is required. 

lfthe substance(s) are listed in NY-2C Tables 9-10 sampling for appropriate indicator parameters may be required, e.g., substituting BODS for 

methanol, substituting toxicity testing for demeton. Discharge volume may be calculated by measuring the depth of water within the containment 

area times the wetted area converted to gallons or by other suitable methods. Form NY -2C is available on the NYSDEC web site. Contact the facility 

inspector for further guidance. In all cases flow and pH monitoring is required. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 22 of 28 

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· DISCHARGE NOTIFICATION REQUIREMENTS 

a) The permittee shall, except as set forth in (c) below, maintain the existing identification signs at all outfalls to surface waters, 

which have not been waived by the Department in accordance with 17 -0815-a. The sign( s) shall be conspicuous, legible and in 

as close proximity to the point of discharge as is reasonably possible while ensuring the maximum visibility from the surface water 

and shore. The signs shall be installed in such a manner to pose minimal hazard to navigation, bathing or other water related 

activities. If the public has access to the water from the land in the vicinity of the outfall, an identical sign shall be posted to be 

visible from the direction approaching the surface water. 

b) 

The signs shall have minimum dimensions of eighteen inches by twenty four inches (18" x 24") and shall have white letters on 

a green background and contain the following information: 

N.Y.S. PERMITTED DISCHARGE POINT 

SPDES PERMIT No.: NY ___ _ 

OUTFALL No. : __ 

For information about this permitted discharge contact: 

Permittee Name:-----------------------------------

Permittee Contact:-----------------------------------'--

Permittee Phone: ) - ### -#### 

OR: 

NYSDEC Division of Water Regional Office Address : 

NYSDEC Division of Water Regional Phone: { ) - ### -#### 

For each discharge required to have a sign in accordance with a), the permittee shall provide for public review at a repository 

accessible to the public, copies ofthe Discharge Monitoring Reports (DMRs) as required by the RECORDING, REPORTING 

AND ADDITIONAL MONITORING REQIDREMENTS page of this permit. This repository shall be open to the public, at 

a minimum, during normal daytime business hours. The repository may be at the business office repository of the permittee or 

at an off-premises location of its choice (such location shall be the village, town, city or county clerk's office, the local library 

or other location as approved by the Department). In accordance with the RECORDING, REPORTING AND ADDITIONAL 

MONITORING REQIDREMENTS page of your permit, each DMR shall be maintained on record for a period of three years. 

c) If, upon November 1, 1997, the permittee has installed signs that include the information required by 17 -0815-a(2)( a), but do not 

meet the specifications listed above, the permittee may continue to use the existing signs for a period of up to five years, after 

which the signs shall comply with the specifications listed above. · 

d) The permittee shall periodically inspect the outfall identification signs in order to ensure that they are maintained, are still visible 

and contain information that is current and factually correct. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 23 of 28 

WATER TREATMENT CHEMICAL (WTC) REQIDREMENTS (9199) 

New or increased use of a WTC requires prior DEC review and authorization. At a minimum, the permittee must notifY the DEC in writing 

of its intent to change WTC use by submitting a completed WTCFX Form for each WTC. The DEC will review that submittal and 

determine if a SPDES permit modification is necessary or whether WTC review and authorization may proceed outside of the formal permit 

administrative process. The majority of WTC authorizations do not require formal SPDES permit modification. WTCs which are 

used in closed systems and cannot be discharged or those which are discharged to municipal STP do not require DEC review. WTC use 

and discharge questions or requests for forms should be directed to the DEC staff person who developed your SPDES permit. If you 

are not sure who that is, contact the DEC staff person who last inspected your facility. 

Examples ofWTCs include, biocides, coagulants, conditioners, corrosion inhibitors, defoamers, flocculants, scale inhibitors, sequestrants, 

and settling aids. DEC staff may also direct you to use the WTCFX Form for review and authorization of substances other than WTCs, 

e.g. process chemicals. 

Generic WTC Usage Requirements 

l. WTC usage shall not exceed the usage rate reported by the permittee or authorized below, whichever is less. 

2. The discharge shall not cause or contribute to a violation of water quality or an exceedance of AWQC. 

3. The permittee must maintain a logbook of all WTC use, noting for each WTC the date, time, exact location, and amount of each 

dosage, and, the name of the· individual applying or measuring the chemical. The logbook must also document that adequate 

process controls are in place to ensure that excessive levels ofWTCs are not used and subsequently discharged through outfalls. 

The permittee shall retain the logbook data for a period of at least 3 years. This period may be extended by request of the OEC. 

4. The permittee shall provide an annual report, attached to the December DMR, containing the following information fpr each 

outfall: the current list ofWTCs authorized for use and discharge by the DEC, for each WTC the amount in pounds used during 

the year, identification of authorized WTCs the permittee no longer uses, and any other pertinent information. 

L" IS t 0 fWTC s u A th onze . d fi or U sean dD' 1sc h arge 

Affected Outfall(s) Dosage (lbs/day) WTC Manufacturer and Product Name WTC Function 

Avg Max 

002 10 20 BetzDearbom Cortrol IS l 050 Oxygen scavenger 

001, 002,003 150 175 BetzDearborn Flowgard POT6103 Corrosion inhibitor 

001 via OIA 270 306 GE Betz Klaraid CDP450 Coagulant 

002 0.8 2.0 GE Betz Optisperse ADJI 030 Anti foam 

. 002 15 20 GE Betz Optisperse AP0520 Dispersant 

001 via OIA 3.0 5.4 GE Betz Polyfloc APII20 Flocculant 

002 10 40 BetzDearborn Stearnate NA0660 Neutralizing agent 

002 20 40 BetzDearbom Stearnate NF5000 Corrosion inhibitor 

001 via O!A 7800/17300 gal Calcium chloride Fluoride capture 

001, OJA, 002,003,005, & 010 max 50,+ 1.2@ 003 Chlorine Disinfection 

001 4.73 lbs/acre ft Copper sulfate Algaecide 

001 via OlA/OIB Hydrochloric acid pH adjust. & 0 lB de-scaling 

001 via OlA/OlB Sodium hydroxide pH adjustment 

• -AuthoriZed WTCs must e1ther be bsted above or Identified m a letter sent to the pernnttee by the DEC subsequent to Issuance of this 

permit page. In cases where a WTC is listed above and in a letter from the DEC, the more recent document will control. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 24 of 28 

C:\MyFlles\0000132p,07mod.sm.wpd 

MONITORING LOCATIONS 

The permittee shall take samples and measurements, to comply with the monitoring requirements specified in this permit, at the 

location(s) specified below: 

Outfall 001 the effluent from the final treatment unit. 

Outfall 0 1A the effluent from the fmal carbon unit at the weir box, flow monitoring may be performed on the equalization tank effluent. 

Outfall 01B- the effluent from the fmal breakpoint chlorination unit. 

Outfall 01 C - the landfill leachate prior to admixture with other wastewaters. 

Outfall 002 - the effluent from the fmal treatment unit 

Outfall 003 - the effluent from the fmal carbon unit 

Outfall 005 - at the existing pipe invert where the pipe discharges to the St. Lawrence River. 

Outfall 008- at the existing flow measurement weir. 

Outfall 01 0 - at the existing flow measurement weir. 

Outfall 011 -at the sheetpile dam flow measurement weir. 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 25 of 28 

C:\MyFiles\0000132p.07mO<l.sm.wpd 

MONITORING LOCATIONS 

The permittee shall take samples and measurements, to comply with the monitoring requirements specified in this permit, at the 

location(s) specified below: 

RMC - Simplified Outfall Diagram 

No Scale, 11103 

008 

s 

R,P,S,N 

R---__,. 

Route 37 

N,S----1>1 

01C 

.~·-L-...._ ( \ l APC System I '-_ _______ j 

Ra uette River 

= Treatment System • = Monitoring Location 

s 

011 

Wastewaters: 

P = Process/Sewage 

R = Remediation 

N = Noncontact 

S = Storm Water 

S,P 

010 
SPDES PERMIT NUMBER NY0000132 

Part I, Page 26 of 28 

C:\MyFiles\0000132p.07mod.sm.wpd 

SCHEDULE OF COMPLIANCE 

a) The pennittee shall comply with the following schedule. 

Action 

Code 

23099 

01299 

59499 

25099 

25099 

05699 

Outfall 

Number(s) 

east sump, 

001,002, 

003, & 008 

Compliance Action 

A short term monitoring program shall be performed to determine the presence of 

the following substances: 

East Sump contaminated groundwater- priority pollutant metals, total aluminum, 

total cyanide, total fluoride, P AHs, total phenols, and PCB aroclors. 

Outfall 001 -total boron, total lead, total mercury, and total vanadium. 

Outfall 002 - total mercury, total tin, and total vanadium. 

Outfall 003 - total boron, total mercury, total thallium, and total vanadium. 

Outfall 008 -total tin. 

This program shall include the collection and analysis of one 24 hour composite 

sample per week for three consecutive discharge weeks, except only one sample is · 

required for mercury, and mercury and outfall 008 samples must be grabs. Mercury 

analysis must be performed using EPA method 1631. Analytical detection limits 

shall be adequately sensitive to provide meaningful data. Results of sampling, 

together with daily flow measurements, must be summarized and submitted. 

OlA and 003 Submit an approvable Miscellaneous Wastewater Plan which identifies 

miscellaneous contaminated wastewaters and identifies an acceptable procedure for 

handling, treatment, and discharge. 

Implement plan in accordance with the Department's approval. 

Due Date 

12/0112004 

12/0112004 

Upon approval 

002 Submit an approvable outfall VOC trackdown and elimination report. The source 06/0112005 

of the benzene and toluene reported in the 8/17/01 pennit application must be 

identified through waste segment sampling and other means of investigation. These 

substances must either be eliminated from the discharge or the pennittee must 

submit a permit modification request to authorize the routine discharge of these 

substances. 

002 Submit an approvable engineering report detailing measures which are proposed to 06/0112007 

achieve final effluent limitations. 

Commence construction. 

Complete activities in accordance with the Department's approval and comply with 

final effluent limitations. 

06/01/09 

06/01110 

The above compliance actions are one time requirements. The permittee shall comply with the above compliance actions to the 

Department's satisfaction once. When this permit is administratively renewed by NYSDEC letter entitled "SPDES 

NOTICE/RENEW AI.. APPLICATION/PERMIT", the permittee is not required to repeat the submission. The above due dates 

are independent from the effective date of the permit stated in the letter of "SPDES NOTICE/RENEW AI.. 

APPLICATION/PERMIT." 

b) The pennittee shall submit a written notice of compliance or non-compliance with each of the above schedule dates no later than 

14 days following each elapsed date, unless conditions require more immediate notice as prescribed in 6 NYCRR Part 7 50-1.2( a) 

and 7 50-2. All such compliance or non-compliance notification shall be sent to the locations listed under the section of this permit 

entitled RECORDING, REPORTING AND ADDITIONAL MONITORING REQUIREMENTS. Each notice ofnon-corr!Qliance 

shall include the following information: 

Original Fact Sheet (submitted for public 

review May 11-July 22, 2005) 

Revised Fact Sheet (issued with permit 

on March 15, 2007) 

FACT SHEET FOR NPDES PERMIT WA-000295-0 

FACILITY NAME INTALCO ALUMINUM CORPORATION 

SUMMARY 

Fact Sheet Page 1 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
TABLE OF CONTENTS

BACKGROUND INFORMATION ................................................................................................7 

DESCRIPTION OF THE FACILITY .............................................................................7 

History.....................................................................................................................7 

Industrial Process...................................................................................................7 

Discharge Locations...............................................................................................7 

Discharge Descriptions..........................................................................................8 

Diverting Water to the BP Cogeneration Facility.............................................11 

PERMIT STATUS...........................................................................................................11 

SUMMARY OF COMPLIANCE WITH THE PREVIOUS PERMIT ......................13 

WASTEWATER CHARACTERIZATION..................................................................15 

SEPA COMPLIANCE.....................................................................................................17 

PERMIT LIMITATIONS ..............................................................................................................17 

DESIGN CRITERIA .......................................................................................................18 

TECHNOLOGY-BASED EFFLUENT LIMITATIONS.............................................18 

ELIMINATING THE TOTAL SUSPENDED SOLIDS (TSS) 

CONCENTRATION LIMIT FOR OUTFALL 001..........................................23 

REDUCED MONITORING FOR ANTIMONY, NICKEL, B(a)P, COPPER, 

CYANIDE, AND OIL AND GREASE...............................................................24 

SURFACE WATER QUALITY-BASED EFFLUENT LIMITATIONS ...................27 

Numerical Criteria for the Protection of Aquatic Life.....................................27 

Numerical Criteria for the Protection of Human Health.................................27 

Narrative Criteria ................................................................................................28 

Antidegradation ...................................................................................................28 

Effluent Quality....................................................................................................28 

Description of the Receiving Water....................................................................28 

Surface Water Quality Criteria..........................................................................29 

Mixing Zones........................................................................................................30 

Mixing Zone Determinations For Outfalls 001 And 002..................................30 

Diffuser Information............................................................................................34 

Chronic Mixing Zones.........................................................................................35 

Acute Mixing Zones.............................................................................................35 

Consideration of Surface Water Quality-Based Limits for Numeric 

Criteria..................................................................................................................37 

Whole Effluent Toxicity ......................................................................................41 

Toxicity Identification/reduction (TI/RE) .........................................................42 

Cherry Point Herring ..........................................................................................43 

Human Health......................................................................................................45 

Sediment Quality..................................................................................................46 

Fugitive Alumina Impact Study .........................................................................47 

Ground Water Quality Limitations ...................................................................48 

COMPARISON OF EFFLUENT LIMITS WITH THE EXISTING PERMIT 

ISSUED ON SEPTEMBER 1, 1998 ...................................................................49 

Fact Sheet Page 2 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
MONITORING REQUIREMENTS..............................................................................................50 

PERFORMANCE-BASED REDUCTION OF MONITORING 

FREQUENCIES...................................................................................................51 

ACTION LEVELS FOR POLLUTANTS DISCHARGED FROM THE 

STORMWATER POND AND THE SECONDARY WASTEWATER 

TREATMENT SYSTEM ....................................................................................53 

LANDFILL MONITORING ..........................................................................................53 

STORMWATER POND MONITORING.....................................................................54 

EFFLUENT LIMITS BELOW QUANTITATION......................................................54 

EFFLUENT LIMITS BELOW DETECTION..............................................................54 

LAB ACCREDITATION................................................................................................55 

OTHER PERMIT CONDITIONS .................................................................................................55 

OUTFALL 002 DIVERSION..........................................................................................55 

TEMPORARY CURTAILMENT..................................................................................56 

REPORTING AND RECORDKEEPING.....................................................................56 

OPERATION AND MAINTENANCE MANUAL.......................................................57 

SOLID WASTE PLAN....................................................................................................57 

NON-ROUTINE AND UNANTICIPATED DISCHARGES.......................................57 

SPILL PLAN....................................................................................................................58 

TREATMENT EFFICIENCY STUDIES......................................................................58 

Primary Wastewater Treatment System (PWTS) And Secondary 

Wastewater Treatment System (SWTS)............................................................58 

Anode Cooling Water ..........................................................................................58 

OUTFALL EVALUATION............................................................................................58 

BEST MANAGEMENT PRACTICES AND STORMWATER POLLUTION 

PREVENTION PLAN.........................................................................................59 

GENERAL CONDITIONS.............................................................................................59 

PERMIT ISSUANCE PROCEDURES .........................................................................................59 

PERMIT MODIFICATIONS.........................................................................................59 

RECOMMENDATION FOR PERMIT ISSUANCE ...................................................60 

REFERENCES FOR TEXT AND APPENDICES........................................................................61 

APPENDIX A--PUBLIC INVOLVEMENT INFORMATION....................................................62 

APPENDIX B--GLOSSARY ........................................................................................................63 

APPENDIX C--TECHNICAL CALCULATIONS .......................................................................67 

APPENDIX D--RESPONSE TO COMMENTS 

APPENDIX E—MAP OF DISCHARGE LOCATIONS 

APPENDIX F—SUMMARY OF NONCOMPLIANCE 

APPENDIX G—DISCHARGE MONITORING SUMMARY 

Fact Sheet Page 3 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX H—WASTEWATER CHARACTERIZATION 

APPENDIX I—COPPER MONITORING RESULTS 

APPENDIX J—MIXING ZONE ANALYSES 

APPENDIX K—TEMPERATURE ANALYSIS 

APPENDIX L—REASONABLE POTENTIAL TO EXCEED (AQUATIC LIFE CRITERIA 

AND HUMAN HEALTH) ANALYSES FOR OUTFALL 001 

APPENDIX L—REASONABLE POTENTIAL TO EXCEED (AQUATIC LIFE CRITERIA 

AND HUMAN HEALTH) ANALYSES FOR OUTFALL 002 

APPENDIX M—ACUTE AND CHRONIC WET TEST RESULTS FOR OUTFALLS 001 

&002 

APPENDIX N—LANDFILL MONITORING RESULTS 

APPENDIX O—PERFORMANCE BASED REDUCTION OF MONITORING 

FREQUENCIES 

Fact Sheet Page 4 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
INTRODUCTION 

The Federal Clean Water Act (FCWA, 1972, and later modifications, 1977, 1981, and 1987) 

established water quality goals for the navigable (surface) waters of the United States. One of 

the mechanisms for achieving the goals of the Clean Water Act is the National Pollutant 

Discharge Elimination System of permits (NPDES permits), which is administered by the 

Environmental Protection Agency (EPA). The EPA has authorized the State of Washington to 

administer the NPDES permit program. Chapter 90.48 RCW defines the Department of 

Ecology's (Ecology) authority and obligations in administering the wastewater discharge permit 

program. 

The regulations adopted by the State include procedures for issuing permits (Chapter 173-220 

WAC), water quality criteria for surface and ground waters (Chapters 173-201A and 200 WAC), 

and sediment management standards (Chapter 173-204 WAC). These regulations require that a 

permit be issued before discharge of wastewater to waters of the state is allowed. The 

regulations also establish the basis for effluent limitations and other requirements which are to be 

included in the permit. One of the requirements (WAC 173-220-060) for issuing a permit under 

the NPDES permit program is the preparation of a draft permit and an accompanying fact sheet. 

Public notice of the availability of the draft permit is required at least thirty days before the 

permit is issued (WAC 173-220-050). The fact sheet and draft permit are available for review 

(see Appendix A--Public Involvement of the fact sheet for more detail on the Public Notice 

procedures). Appendices B and C include a glossary of the terms used in this fact sheet and a 

reference to access the spreadsheet tools commonly used by Ecology. 

The fact sheet and draft permit were reviewed by the Permittee. Errors and omissions identified 

in that review were corrected before going to public notice. After the public comment period 

closed, Ecology summarized the substantive comments and the responses to each comment. The 

summary and response to comments is included in Appendix D of this fact sheet. Parties who 

submitted comments will receive a copy of Ecology's responses. The fact sheet was revised after 

the public comment period (which ended on July 22, 2005) to correct errors, to expand on 

explanations for conditions in the permit, and to explain changes that were made to the permit in 

response to public comment and other policy updates. 

Fact Sheet Page 5 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
GENERAL INFORMATION 

Applicant Intalco Aluminum Corporation 

Facility Name and Address Intalco Aluminum Corporation 

4050 Mountain View Road 

P.O. Box 937 

Ferndale, Washington 98248 

Type of Facility: Primary Aluminum Smelting 

SIC Code 3334 

Discharge Locations 

Outfall 001 

Outfall 002 

Outfall 003 

Outfall 004 

Outfall 005 

Outfall 011 

Outfall 012 

Strait of Georgia 

Latitude: 48° 50' 26.8" N Longitude: 122° 43' 13.6" W 

Latitude: 48o 50’ 22” N Longitude: 122o 42’ 56.1” W 

Latitude: 48o 50’ 49” N Longitude: 122o 42’ 56.1” W 

Latitude: 48o 50’ 13” N Longitude: 122o 42’ 52” W 

Latitude: 48o 50’ 31” N Longitude: 122o 42’ 49” W 

Latitude: 48o 50’ 33” N Longitude: 122o 42’ 53” W 

Latitude: 48o 50’ 25” N Longitude: 122o 42’ 53” W 

Water Body ID Number WA-01-0030 

Receiving Water Strait of Georgia 

Fact Sheet Page 6 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
BACKGROUND INFORMATION 

DESCRIPTION OF THE FACILITY 

HISTORY

The Intalco Aluminum Corporation (Intalco) began the operations of a primary aluminum 

smelter near Ferndale, Washington in 1966. At full production the facility employs 

approximately 800 people. The smelter is currently operating at approximately 40% capacity 

with a workforce of 400 people. 

INDUSTRIAL PROCESS

The Ferndale facility produces primary aluminum metal by the Hall-Heroult reduction process. 

The facility operates three pot lines, which contain a total of 720 side worked, pre-bake anode 

reduction cells. The smelter, in the past, has been capable of producing approximately 307,000 

tons of aluminum metal per year at full production. All metal produced is cast on-site into 

various sizes and forms: sows, tees, slabs, billets, and ingots. 

Potline A was shutdown in June of 2001. Intalco has been operating Potlines B and C at a 

reduced production level since then. Intalco signed a 5-year power contract with Bonneville 

Power Association on August 01, 2006. Intalco proposes to operate two fully operational 

potlines (a total of 480 pots operating in Potlines A and C) by mid-2007. They propose to do this 

by migrating pots from Potline B to Potline C and starting up Potline A. 

DISCHARGE LOCATIONS

The facility is located near Cherry Point along the Strait of Georgia. The process wastewater 

outfall line (001) is suspended from the shipping pier and extends approximately 1100 feet 

from the edge of the shoreline. The stormwater outfall line (002) is approximately 800 feet 

south of the process outfall line and extends approximately 250 feet from the shoreline in a 

westerly direction. The approximate locations of Outfalls 001, 002, 003, 004, 005, 011, and 

012 are as follows. The locations of these discharges are also shown on the map in Appendix E. 

Outfall Latitude Longitude 

001 48o 50’ 26.8” N 122o 43’ 13.6” W 

002 48o 50’ 22” N 122o 42’ 56.1” W 

003 48o 50’ 49” N 122o 42’ 56.1” W 

004 48o 50’ 13” N 122o 42’ 52” W 

005 48o 50’ 31” N 122o 42’ 49” W 

011 48o 50’ 33” N 122o 42’ 53” W 

012 48o 50’ 25” N 122o 42’ 53” W 

Fact Sheet Page 7 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
DISCHARGE DESCRIPTIONS

Intalco maintains a total of seven outfalls (001, 002, 003, 004, 005, 011, and 012). The discharge 

from each of the outfalls is described below. 

Outfall 001: 

Non-contact cooling water from Intalco’s air compressors is the largest component of the 

discharge at Outfall 001. Treated wastewaters from Intalco’s primary and secondary wastewater 

treatment systems, sanitary lagoon, anode contact cooling water from the carbon plant, and water 

heater/steam cleaner systems are commingled with the non-contact cooling water before 

discharge at Outfall 001. Major pollutants include total suspended solids (TSS), fluoride, and 

aluminum. Other possible pollutants include cyanide, benzo(a)pyrene, and oil and grease. 

The effluent to Outfall 001 is conveyed through a 24-inch diameter fiberglass reinforced plastic 

pipe and discharged through a 24-inch diameter, 120-foot long diffuser. The discharge is 

continuous and in the past has averaged 3.0 million gallons per day (MGD), with a maximum of 

5.0 MGD. The Permittee is supplied with treated (coagulated) water from the Nooksack River 

by the Whatcom Public Utility District #1 (PUD). The plant’s air compressors are water-cooled 

by the PUD water. That cooling water constitutes approximately 80-90% of the volume of 

discharge at Outfall 001. 

Intalco’s Primary Wastewater Treatment System (PWTS) treats wastewater from the potline’s air 

pollution control system (wet scrubbers). The PWTS consists of two clarifiers (the older clarifier 

is only used when the other clarifier is shut down for maintenance). The clarifier provides 

treatment in the form of precipitation and sedimentation to remove solids and to reduce the 

turbidity in the wet scrubber wastewater. Cooling water from the cast house is used as makeup 

water in the PWTS. A small stream of blowdown from the boiler used to heat the caustic 

storage tank (part of the Secondary Wastewater Treatment System described below) is also 

treated in the PWTS. Most of the treated effluent from the clarifier is recycled back into the wet 

scrubbers. The remainder of the effluent is routed to the Secondary Wastewater Treatment 

System (SWTS) for removal of dissolved fluoride. 

The SWTP is comprised of an equalization tank (ET) and two treatment trains running in 

parallel. Each treatment train consists of a reaction tank and a flocculation tank. Additional 

tanks supporting the treatment process are those used for storage of the treatment chemicals 

(calcium chloride, sulfuric acid, and coagulant). Wastewater routed from the PWTS to the 

SWTS for fluoride treatment is pumped into the ET where it is combined with leachate from the 

on-site landfill leachate collection system. Pollutants in the PWTS effluent include high 

concentrations of particulate and fluoride. The landfill leachate contains high concentrations 

of fluoride and occasional high concentrations of cyanide. Wastewater in the equalization tank 

is pumped to the treatment train in the SWTS. Chemical treatment is followed by further 

treatment of the effluent in the form of sedimentation of solids in the clarifier. Some of the 

solids that settle out in the clarifier are recycled back into the clarifier. The remainder of the 

solids (sludge) are dewatered in a rotary vacuum drum filter. The dewatered sludge is disposed 

of in the Permittee’s on-site RCRA landfill. 

Fact Sheet Page 8 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Intalco’s domestic wastewater is discharged to the plant’s aerated sanitary lagoon. Effluent from 

the lagoon is treated by ultraviolet (UV) disinfection before being discharged into a pipeline to 

Outfall 001. Total discharge volume is continuous and in the past has averaged 0.035 MGD. 

The flow rate is expected to go down with the reduction in workforce to less than 400 

employees. The permit allows for a reduction in removal efficiency when the average number of 

employees in a month is below 400. The permitted pollutants in the discharge are biochemical 

oxygen demand (BOD), total suspended solids (TSS), and fecal coliforms. 

Anode contact cooling water is generated during the anode production process. Intalco’s anodes 

are made from petroleum coke and coal tar pitch. The coke and pitch are mixed together and 

then shaped into an anode with a mechanical press under high temperature and pressure. To 

facilitate maintaining the shape of the anode, the anodes are cooled with a strong spray of cold 

water after removal from the press. During the spraying process, the contact water is 

contaminated with coke and pitch containing Polycyclic Aromatic Hydrocarbons (PAHs) 

[including benzo(a)pyrene (B(a)P)]. This wastewater is filtered through a screen (to remove 

solids with adsorbed PAHs). The filtered wastewater is then discharged to the process sewer 

system without any additional treatment before it is discharged at Outfall 001. The permit 

requires the Permittee to conduct a treatment efficiency study of the anode contact cooling water 

filtration system to determine if it meets all known available and reasonable methods of 

treatment (AKART) standards. The treatment efficiency study is discussed in more detail later 

on in this document. 

Intalco operates a steam-cleaning station in each of three maintenance shops (Automotive, 

Central, and Annex). These stations are used to clean various pieces of plant equipment prior to 

maintenance activities. The wastewater from these stations is treated with sand filtration to 

remove suspended solids and with a coalescing filter to remove oil and grease. The filtered 

wastewater is then discharged to the process sewer system without any additional treatment 

before it is discharged at Outfall 001. 

Outfall 002: 

Due to the nature of the aluminum smelting process, there is potential for stormwater to contact 

raw materials, byproduct, or waste materials that could contaminate the stormwater. To mitigate 

the discharge of any suspended solid material, all stormwater collected from the industrial 

portion of the plant site is routed through a stormwater settling pond in the southwest corner of 

the plant. The stormwater pond provides approximately 1.7 million gallons of capacity. The 

pond (built in 1992) is a flow-through system designed to allow solids to settle from the 

stormwater. The stormwater pond is designed to treat maximum stormwater flow rates up to 30 

cubic feet per second (cfs). The pond was conservatively sized (1.9 million gallons) based on the 

6-month, 24-hour design storm volume of 1.5 million gallons. The hydraulic capacity of the 

stormwater system (including diversion structures) was designed for a 100-year, 24-hour (4.0 

inches of rain) storm. All flow in excess of 28 cfs is diverted around the pond via a series of 

three overflow structures. 

Stormwater from outside the industrially developed plant site flows through two separate ditches. 

The two separate ditches combine with the stormwater pond effluent at the Outfall 002 

monitoring and compliance point (D-10). At this point, the water is further treated to remove oil 

Fact Sheet Page 9 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
and other floating materials with a continuously operated mechanical oil skimmer. Absorbent 

materials (e.g. socks) are located immediately prior to the location where the effluent enters the 

discharge pipe. 

The discharge to Outfall 002 is conveyed through a 30-inch diameter fiberglass reinforced plastic 

pipe and has no diffuser. This discharge, in the past, has been continuous and has averaged 0.6 

MGD, with a typical range of 0.1 to 2.4 MGD for a monthly average. During storm events the 

flow may reach levels as high as 12.5 MGD. The primary sources of water for this discharge 

include stormwater runoff from the 320 acres in-plant area and also the off-plant area of Intalco. 

Major pollutants discharged from Outfall 002 include total suspended solids, fluoride, and 

aluminum. 

Periods of zero discharge occur at Outfall 002 during dry summer weather. 

Outfalls 003, 004, and 005: 

Outfall 003 discharges stormwater runoff and leachate from industrial solid waste in a historic 

landfill known as the Beach I Landfill. This landfill was operated from 1966 to 1978 by Intalco 

and is located northwest of the main plant site along a bluff overlooking the Strait of Georgia. 

Outfall 004 discharges stormwater runoff and leachate from industrial solid waste in a historic 

landfill known as Beach II Landfill. This landfill was operated from 1971 to 1984 by Intalco and 

is located southwest of the main plant site along a bluff overlooking the Strait of Georgia. 

Outfall 005 discharges stormwater runoff and leachate from industrial solid waste in a historic 

landfill known as the Construction Debris Landfill. This landfill was operated from 1966 to 

1973 by Intalco and is located due west of the main plant site along a bluff overlooking the Strait 

of Georgia. 

The control and elimination of these discharges is discussed in more detail in the Landfill 

Monitoring section later on in this document. 

Outfalls 011 and 012: 

The silo storage area at the entrance to the pier contains three 100-foot diameter alumina storage 

silos. The drainage area of the alumina silo storage area is about 550 feet by 200 feet (2.5 acres) 

and is divided into two watersheds. 

The northern portion of the silo storage area drains to a single catch basin and discharges to 

Outfall 011. This outfall is embedded deep in the riprap shoreline along the northern edge of the 

silo storage area. Drainage from the stormwater collection ditch on the north side of the road 

enters a catch basin at the southeast corner of the truck escape ramp and is also discharged at 

Outfall 011. Additional drainage from the terraces on the hillside east of the road is conveyed 

through a series of catch basins and drains to the same catch basin at southeast corner of the 

truck escape ramp and is discharged at Outfall 011. Major pollutants include TSS, fluoride, and 

aluminum. Intalco is required to reduce the TSS concentration in the discharge at Outfall 011 by 

implementing the BMPs in Condition S14.A. of the permit. 

Fact Sheet Page 10 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
The middle and southern portion of the silo storage area drain to three catch basins arranged in a 

north-south alignment and connected in series in a single pipe. These three southern most catch 

basins discharge to Outfall 012. This outfall is embedded deep in the riprap shoreline along the 

southern edge of the silo storage area. Outfall 012 is located in an area that is difficult to access 

due to vegetation and is only accessible on foot. Major pollutants include total suspended solids 

(TSS), fecal coliform, fluoride, and aluminum. The results of an analysis of the Outfall 012 

discharge showed that the TSS concentration was higher than the Ecology stormwater 

benchmark and the fecal coliform results were equal to the commonly used monthly average 

fecal coliform permit limit. On May 12, 2004 Ecology inspected Outfall 012 and noticed that 

there was a lot of animal waste in the vicinity of the outfall. The drainage area to Outfall 012 is 

localized and there are no sources of human waste in this area. Therefore, Ecology believes that 

animal waste, not human waste, contributed to the high fecal coliform levels observed at Outfall 

012. Intalco is required to reduce the TSS concentration in the discharge at Outfall 012 by 

implementing the BMPs in Condition S14.A. of the permit. 

The Permittee will be required to collect monthly grab samples from the catch basin sumps for 

Outfalls 011 and 012 when flow is available. The samples will be analyzed for TSS, aluminum, 

and fluoride. After one year of testing at Outfalls 011 and 012, the Permittee will have the 

option to petition Ecology in writing to reduce or eliminate this monitoring. 

DIVERTING WATER TO THE BP COGENERATION FACILITY

Whatcom County Public Utility District No. 1 (PUD) owns the water rights for water in the 

Ferndale area and Intalco and the BP Cherry Point refinery contract for water through the PUD. 

The PUD withdraws water from the Nooksack River. Intalco has recently completed an 

agreement with the PUD and BP for a water reuse project. Under the agreement, Intalco will 

provide the water needed to operate the proposed BP cogeneration facility. Intalco will divert up 

to 4.5 MGD of non-contact, once-through cooling water normally discharged through Outfall 

001, to the cogeneration facility for use in their evaporative cooling system. 

Implementation of this system is expected about six months prior to the start-up of the 

cogeneration facility. This project will allow for the reuse of industrial wastewater rather than 

consuming new water resources from the Nooksack River.

PERMIT STATUS 

The previous permit for this facility was issued on September 1, 1998 and modified on June 1, 

2000 and January 4, 2002. The effluent limitations for Outfall 001, Outfall 002, and the Sanitary 

Lagoon were as shown in the following tables: 

Fact Sheet Page 11 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Effluent Limitations: Outfall # 001

Parameter Units Monthly Average Daily Maximum

Total Suspended Solids

lbs/day

mg/l 

150 

10 

185 

-- 

Fluoride lbs/day 68 296 

Aluminum lbs/day 10.3 30 

Free Cyanide mg/l <0.012 0.012 

Benzo(a)Pyrene mg/l <0.01 0.01 

Oil and Grease mg/l 5 10 

pH Within the range of 6.0 - 9.0 

Effluent Limitations: Outfall # 002 

Parameter Units Monthly Average Daily Maximum

Total Suspended Solids mg/l 35 75 

Fluoride mg/l 35 50 

Aluminum mg/l 10 15 

Benzo(a)Pyrene mg/l -- <0.01 

Oil and Grease mg/l 5 10 

pH Within the range of 6.0 - 9.0 

Fact Sheet Page 12 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Effluent Limitations: Sanitary Lagoon Discharge 

Parameter Units 30-Day Average 7-Day Average

Biochemical Oxygen Demand mg/l 

lbs/day 

45.0 

22.4 

65.0 

32.4 

Total Suspended Solids mg/l 

lbs/day 

45.0 

22.4 

65.0 

32.4 

Fecal Coliform Colonies/100 ml 200 400 

Chlorine mg/l Minimum - 0.1 Maximum - 1.5 

pH Within the range of 6.0 - 9.0 

An application for permit renewal was submitted to Ecology on March 5, 2003 and accepted by 

on June 24, 2003. Additional 2F forms for Outfalls 003, 004, and 005 were submitted to and 

accepted by Ecology. 

SUMMARY OF COMPLIANCE WITH THE PREVIOUS PERMIT 

The facility last received an unannounced Class II inspection on May 23-24, 2006. The facility 

was found to be in compliance with the permit limits at the time of the inspection. The last nonsampling inspection was completed on May 03, 2006. 

In general, the Permittee has remained in compliance with effluent limits and other permit 

requirements during the previous permit term, based on monthly Discharge Monitoring Reports 

(DMRs) and inspections conducted by Ecology. Appendix F summarizes the incidents of 

noncompliance. 

The previous permit required a number of special studies to be completed during the term of the 

permit. Studies of the effluent included annual priority pollutant testing, acute and chronic 

toxicity testing, a stormwater characterization study, and stormwater sampling. Other studies or 

requirements included an outfall evaluation, preparation of stormwater pollution prevention 

plans, a sediment study, an engineering study for chlorination, preparation of a stormwater pond 

operational plan and engineering report, development of a potline ditch cleaning schedule, an 

aluminum and fluoride source study, and a potroom roof run-off study. All of the studies were 

completed as required by the NPDES permit and are discussed in the next section and later in 

this document. 

REVIEW OF PREVIOUS PERMIT REQUIREMENTS 

1. Primary Wastewater Treatment System Operational Plan:

Intalco is required to operate process wastewater treatment systems according to 

procedures and criteria described in an operating plan. Condition S.7 of the previous 

Fact Sheet Page 13 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
permit requires Intalco to update and maintain operational plans on site for the process 

wastewater treatment systems. Intalco has not updated the operational plan for the 

primary treatment system. Condition S10.A of the permit requires Intalco to update their 

O&M Manual to include the PWTS. 

2. Secondary Wastewater Treatment System Operational Plan: 

Intalco submitted a copy of the updated operational plan for the secondary treatment 

system in March 2004. The operational plan for the SWTS fulfills the requirements of 

the previous permit.

3. Sanitary Wastewater Treatment System Operational Plan: 

Intalco submitted a copy of the “Sanitary Water Treatment Facility Operations and 

Maintenance Manual” in March 2004. This manual fulfills the requirements of previous 

permit. 

4. Stormwater Pond Operational Plan: 

Condition S7. of the previous permit required Intalco to develop and maintain a 

Stormwater Pond Operational Plan. In order to meet the requirements for the operational 

plan, Intalco conducted site hydrologic and rainfall characterizations and developed a 

stormwater model. Intalco was also required to submit an as-built engineering report 

which included design criteria for TSS removal efficiencies at the stormwater pond. 

Intalco submitted the operating plan and the as-built engineering report as sections of the 

Stormwater Runoff Study Final Report dated July 27, 2001 (final report). Ecology 

reviewed the final report and determined that Intalco had fulfilled the requirements of the 

previous permit. The stormwater pond’s influent flow design criteria (in Condition S4. of 

the permit) is taken from Intalco’s report titled “Proposed Stormwater Pond Outfall 

Changes” (dated October 14, 2003). Intalco made recommendations regarding the 

maintenance of the stormwater pond in the final report that have been included as 

requirements in Condition S14.A. of the permit. 

5. Stormwater Pollution Prevention Plan: 

Condition S.9. of the previous permit required Intalco to submit a Stormwater Pollution 

Prevention Plan (SWPPP). Intalco was required to implement the operational and source 

control BMPs outlined in the SWPPP, submit a schedule for cleaning alumina and other 

debris from the potline ditches, and conduct a study to determine the contributions of 

aluminum and fluoride to the stormwater system from runoff from the roofs of the 

potroom buildings. 

Intalco submitted the SWPPP on August 27, 1999, additional information for the SWPPP 

in January 2000, the schedule for cleaning the potline ditches in January of 2000, and the 

final potroom roof runoff study results in July of 2001. Intalco leased a new more 

effective sweeper and began implementing the potline ditch cleaning schedule in 

Fact Sheet Page 14 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
September 2000. Based on a review of these documents, Ecology determined that Intalco 

has fulfilled the requirements of the previous permit. Intalco recommended BMPs and 

other action items in the SWPPP and also in the Stormwater Runoff Study Final Report. 

Condition S14.A. of the permit requires Intalco to implement the BMPs and other action 

items and to update the SWPPP. 

6. Stormwater Characterization Study:

Condition S11. of the previous permit required Intalco to submit a stormwater sampling 

and analysis plan to Ecology for review and approval within the first year of the permit. 

The purpose of the Plan was to characterize the stormwater pond performance to 

determine the stormwater pond’s pollutant contribution to Outfall 002 versus off-site 

contributions. Intalco submitted a final stormwater sampling and analysis plan in March 

2000. Intalco conducted the stormwater characterization study from April 2000 through 

March 2001. The results of the study are compiled in a document entitled “Stormwater 

Runoff Study Final Report” dated July 27, 2001. Ecology reviewed the results of the 

study and determined that the submittal met the requirements of the previous permit. The 

final report included BMPs that Intalco recommended. Ecology requires Intalco to 

implement and follow these BMPs in Condition S14.A. of the permit. 

WASTEWATER CHARACTERIZATION 

The proposed wastewater discharges were characterized by Intalco in the permit application 

process for conventional pollutants, metals, cyanide, volatile organic compounds, acid 

compounds, base neutral compounds, and pesticides. Long term average values reported below 

for Outfalls 001 and 002 and the sanitary lagoon effluent are based on extensive (daily to 

weekly) monitoring completed during the term of the permit. The table below also includes long 

term averages for pollutants with significant concentrations and/or of interest; the metals and 

organics listed include all of those that were quantified at greater than detection limits. These 

long term averages were calculated from six years of annual priority pollutant testing (1999-

2004). Additional information is included in Appendices G and H. 

Fact Sheet Page 15 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Wastewater Characterization (Long Term Average Value) 

Parameter Concentration Mass 

OUTFALL 001

TSS 4.20 mg/L 106 lbs/day 

Fluoride 0.883 mg/L 23.4 lbs/day 

Aluminum 0.57 mg/L 15.82 lbs/day 

Free Cyanide <0.005 mg/L 0.0025 lbs/day 

B(a)P <0.0001 mg/L 0 lbs/day 

Oil & Grease 0.40 mg/L 10.4 lbs/day 

Temperature 13.12°C 

pH 6.3-8.3 

Ammonia 0.105 mg/L 

Chlorine 0.025 mg/L 

Nitrate-Nitrite 0.644 mg/L 

Nickel 0.008 mg/L 

Zinc 0.012 mg/L 

Phenols 0.068 mg/L 

Total Organic Carbon 1.9 mg/L 

OUTFALL 002

TSS 7.72 mg/L 52.6 lbs/day 

Fluoride 16.1 mg/L 68.5 lbs/day 

Aluminum 0.57 mg/L 17.96 lbs/day 

Free Cyanide <0.005 mg/L -- 

B(a)P <0.0001 mg/L -- 

Oil & Grease 0.47 mg/L 2.41 lbs/day 

Temperature 13.12°C 

pH 6.3-8.2 

Ammonia 0.077 mg/L 

Nitrate-Nitrite 0.088 mg/L 

Arsenic 0.0004 mg/L 

Chromium 0.0006 mg/L 

Fact Sheet Page 16 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Wastewater Characterization (Long Term Average Value) – Continued 

Parameter Concentration Mass 

OUTFALL 002 (continued) 

Nickel 0.015 mg/L 

Zinc 0.045 mg/L 

SANITARY LAGOON EFFLUENT

BOD 13.35 mg/L 4.34 lbs/day 

TSS 9.55 mg/L 3.08 lbs/day 

Fecal Coliform 1.7 cfu/100mL 

pH 6.3-8.2 

SEPA COMPLIANCE 

This permit renewal has no SEPA compliance issues. 

PERMIT LIMITATIONS 

Federal and State regulations require that effluent limitations set forth in a NPDES permit must 

be either technology- or water quality-based. Technology-based limitations are based upon the 

treatment methods available to treat specific pollutants. Technology-based limitations are set by 

regulation or developed on a case-by-case basis (40 CFR 125.3, and Chapter 173-220 WAC). 

Water quality-based limitations are based upon compliance with the Surface Water Quality 

Standards (Chapter 173-201A WAC), Ground Water Standards (Chapter 173-200 WAC), 

Sediment Quality Standards (Chapter 173-204 WAC) or the National Toxics Rule (Federal 

Register, Volume 57, No. 246, Tuesday, December 22, 1992). The more stringent of these two 

limits must be chosen for each of the parameters of concern. Each of these types of limits is 

described in more detail below. 

The limits in this permit are based in part on information received in the application. The 

effluent constituents in the application were evaluated on a technology- and water quality-basis. 

The limits necessary to meet the rules and regulations of the State of Washington were 

determined and included in this permit. Ecology does not develop effluent limits for all 

pollutants that may be reported on the application as present in the effluent. Some pollutants are 

not treatable at the concentrations reported, are not controllable at the source, are not listed in 

regulation, or do not have a reasonable potential to cause a water quality violation. Effluent 

limits are not always developed for pollutants that may be in the discharge are not reported as 

present in the application. In those circumstances the permit does not authorize discharge of the 

non-reported pollutants. Effluent discharge conditions may change from the conditions reported 

in the permit application. If significant changes occur in any constituent, as described in 40 CFR 

122.42(a), the Permittee is required to notify Ecology. The Permittee may be in violation of the 

permit until the permit is modified to reflect additional discharge of pollutants. 

Fact Sheet Page 17 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
DESIGN CRITERIA 

Intalco conducted a study to determine current capacities and treatment efficiencies of their 

wastewater treatment systems. Intalco submitted the results of that study to Ecology in a 

document titled “Primary Water Treatment Plant, Secondary Water Treatment Plant, and 

Sanitary Water Treatment Facility Capacities and Efficiencies” dated June 2004. These reports 

provide preliminary information. The permit will require treatment efficiency studies, when 

warranted, to determine the criteria necessary to monitor the efficiency of these systems. 

TECHNOLOGY-BASED EFFLUENT LIMITATIONS 

Ecology reviewed the applicant's Form R (Toxic Release Inventory Reporting Form), list of 

Superfund Amendments and Reauthorization Act of 1986 (SARA) Title III hazardous substances, 

and Form 2C of the NPDES Permit Application. also reviewed the discharge monitoring reports 

(DMRs), study results, and wastewater inspection results generated during the term of the previous 

permit. 

After reviewing this data, Ecology determined that, in general, the effluent limits from the previous 

permit will remain the same. These limits are believed to be effective regulatory controls. 

Technology-based limitations are set by regulations or developed on a case-by-case basis. EPA 

periodically evaluates specific industries, such as primary aluminum smelting, and publishes 

federal effluent guidelines which represent technology-based effluent limitations. In 

Washington, state law imposes a requirement to provide all known available and reasonable 

methods of treatment (AKART), and this requirement is functionally an overlay on the federal 

requirements. AKART may dictate more stringent technology-based limits than the federal 

effluent guidelines. 

The applicable federal effluent guidelines for the primary aluminum smelting subcategory were 

promulgated by EPA on July 7, 1987 and are published in 40 CFR 421 Subpart B. EPA 

periodically reviews its effluent guidelines and determines when guidelines for specific 

industries need to be updated. In EPA’s Technical Support Document for the 2004 Effluent 

Guidelines Program Plan EPA reviewed the primary aluminum smelting subcategory and 

determined that “reduction in pollutant loadings from raw wastewater to discharges indicate that 

the current treatment in the industry should be resulting in 99+ percent reductions for those 

pollutants regulated in the 1990 rule” and that concentrations of benzo(a)pyrene “are generally 

below treatable concentrations and additional reductions of this pollutant may not be possible.” 

EPA determined in 2004 that the effluent guidelines for the entire Nonferrous Metals 

Manufacturing Point Source Category (of which primary aluminum smelting is a subcategory) 

did not need to be revised 

The effluent limitations for toxic, non-conventional, and conventional pollutants at Outfalls 001 

and 002 in the previous permit were established using Best Professional Judgment (BPJ). 

Although the applicant has discharges that are applicable subcategories in the federal effluent 

guidelines in 40 CFR Part 421 - Subpart B, these guidelines were not used to develop the limits. 

The limits for Outfall 001 are performance based and were developed by running a statistical 

Fact Sheet Page 18 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
analysis on two years of representative monitoring data using a method consistent with EPA and 

Ecology effluent limit setting guidelines. 

The performance-based limits are more stringent than the federal effluent guidelines. Ecology 

has determined that the limits for Outfall 001 are based on AKART but is also requiring 

treatment efficiency studies in this permit. A possible outcome of these studies would be a 

refinement of AKART for this facility. 

The concentration limits for the sanitary lagoon are taken directly from the discharge standards and 

effluent limitations for domestic wastewater facilities, Chapter 173-221 WAC. On January 21, 

2004, Intalco submitted a request for an alternative percent removal effluent limitation at the 

sanitary lagoon during periods of reduced operations or temporary curtailment. Ecology reviewed 

the Permittee’s request and determined that the Permittee meets the criteria required in Chapter 

173-221-050 WAC and Chapter V, Section 3.5.1 of Permit Writer’s Manual. Therefore, the 

removal efficiency for BOD and TSS in the sanitary lagoon discharge was reduced from a 

minimum of 65% to 55% when a monthly average of < 400 persons are employed onsite. The 

Permittee is required to report the number of personnel onsite to Ecology in the monthly discharge 

monitoring report. Upon an increase in personnel to > 400 persons monthly average, the removal 

efficiency for BOD and TSS is required to revert to a minimum of 65%. 

Mass-based limits for B(a)P, antimony, and nickel were removed from the 1991 and 1998 

NPDES permits for undefined reasons. Per 40 CFR 122.44(a)(1) and 122.44(1)(2)(ii), Ecology 

is reinstating these limits. Ecology used representative production rates and the federal effluent 

guidelines for the primary aluminum smelting subcategories in 40 CFR 421 to derive the 

respective production-based effluent limits summarized in the table below (see the footnote for a 

discussion of the derivation of the limits). 

PRODUCTION-BASED EFFLUENT LIMITS

Effluent Limitation 

Guideline 

Production-Based 

Effluent Limit 

Production Rate 

million pounds 

(MMlb) 

Maximum 

Day 

(lb/MMlb) 

Maximum 

Monthly 

Average 

(lb/MMlb) 

Daily 

Maximum 

B(a)P (lbs/day) 

Maximum 

Monthly 

Average 

(lbs/day) 

Anode Contact Cooling and Briquette 

Quenching (40 CFR 421.23(b)) 

1.8 0.007 0.003 0.013 0.005 

Potroom Wet Air Pollution Control (40 CFR 

421.23(m)) 2.1 0.056 0.026 0.118 0.055 

Direct Chill Contact Cooling (40 CFR 421.23(q)) 2.1 NA NA NA NA 

B(a)P Permit Limits when aluminum production is greater than 15,614 tons per month 0.13 0.06 

B(a)P Permit Limits when aluminum production is less than or equal to 15,614 tons 

per month 0.065 0.03 

Fact Sheet Page 19 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
PRODUCTION-BASED EFFLUENT LIMITS 

(CONTINUED) 

Effluent Limitation 

Guideline 

Production-Based 

Effluent Limit 

Antimony 

Production Rate 

million pounds 

(MMlb) 

Maximum 

Day 

(lb/MMlb) 

Maximum 

Monthly 

Average 

(lb/MMlb) 

Daily 

Maximum 

(lbs/day) 

Maximum 

Monthly 

Average 

(lbs/day) 

Anode Contact Cooling and Briquette 

Quenching 1.8 0.403 0.18 0.725 0.324 

Potroom Wet Air Pollution Control 2.1 3.204 1.428 6.728 2.999 

Direct Chill Contact Cooling 2.1 2.565 1.143 5.387 2.400 

Antimony Permit Limits when aluminum production is greater than 15,614 tons per 

month 12.8 5.7 

Antimony Permit Limits when aluminum production is less than or equal to 15,614 

tons per month 6.4 2.85 

Effluent Limitation 

Guideline 

Production-Based 

Effluent Limit 

Nickel 

Production Rate 

million pounds 

(MMlb) 

Maximum 

Day 

(lb/MMlb) 

Maximum 

Monthly 

Average 

(lb/MMlb) 

Daily 

Maximum 

(lbs/day) 

Maximum 

Monthly 

Average 

(lbs/day) 

Anode Contact Cooling and Briquette 

Quenching 1.8 0.115 0.077 0.207 0.139 

Potroom Wet Air Pollution Control 2.1 0.913 0.614 1.917 1.289 

Direct Chill Contact Cooling 2.1 0.731 0.492 1.535 1.033 

Nickel Permit Limits when aluminum production is greater than 15,614 tons per 

month 3.7 2.5 

Nickel Permit Limits when aluminum production is less than or equal to 15,614 tons 

per month 1.85 1.25 

Ecology used monthly average production data from 1999 and 2000 to determine the production 

rates used to derive the monthly average limits for each of the processes. The monthly average 

production rates were also used to derive the maximum daily limits because the Permittee had no 

daily production data available. Ecology used the respective actual maximum monthly average 

production rates (converted to a daily maximum production rate assuming 24 hours of operation 

for 30 days each month) to derive the daily maximum production-based limit. 

Because the Permittee has not operated at full production in recent years, Ecology has established 

tiered production limits with the higher tier applicable when production exceeds 15,614 tons per 

month, and the lower tier applicable when production is less than or equal to 15,614 tons per 

month. 15,614 tons per month aluminum production is half the actual maximum monthly average 

production rate that occurred between 1999 and 2000 when the Permittee operated at full 

production. 

The Permittee’s actual maximum monthly average production data for the Anode Contact Cooling 

and Briquette Quenching process was based on 16 hours of production per day. The Permittee 

plans to operate this process 24 hours a day during the next permit cycle. Ecology converted the 

Fact Sheet Page 20 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
maximum monthly average production rate into a maximum daily production rate based on 24 

hour per day operation for a 30 day month per the calculations below. Ecology used the new 

maximum daily production rate to derive the maximum daily limits for the Anode Contact Cooling 

and Briquette Quenching process. 

Calculations: 

Maximum monthly average production rate = 17668 tons per month 

(17668 tons/month)x(month/30 days)= 589 tons/day 

(589 tons/day)/(16 hours/day)= 37 tons/hour 

(37 tons/hour)x(24 hours/day)=888 tons/24 hour day 

(888 tons/day)x(2000lb/ton)x(MM lb/1.0x106 lb)= 1.8 MM lb/day = Maximum Daily Production 

With the netting out allowance for TSS and aluminum at Outfall 001, the intake water (PUD) 

levels were often higher than effluent levels. This resulted in a large number of zeros in the data 

set. After evaluating several different ways to set limits for TSS and aluminum at Outfall 001 

under the “netting out” provision, the permit writer decided to assign limits from the previous 

permit (issued February 14, 1992). The limits for daily maximum and monthly average TSS and 

daily maximum aluminum were determined by multiplying EPA Best Available Technology 

Economically Achievable (BAT) treatability levels by production normalized flows from process 

and non-process wastewater sources. 

The effluent pH limitation in the permit will continue to be 6.0 to 9.0. This limitation is based on 

Best Practicable Control Technology (BPT) from guidelines in 40 CFR Part 421.22. This range 

(6.0 to 9.0) will not result in water quality violations. 

Stormwater discharged at Outfall 002 is managed by a combination of best management 

practices and treatment by a stormwater detention pond, which Ecology has determined 

constitutes AKART for this facility. Because the monitoring data from Outfall 002 are highly 

auto correlated they do not meet the requirements for normal statistical distribution, a 

requirement for proper use of guidelines for establishing performance-based effluent limits. For 

this reason, limits for Outfall 002 are based on Best Professional Judgement (BPJ). 

NETTING OUT 

The industrial water supplied to Intalco by Whatcom County PUD No. 1 is treated Nooksack 

River water. The treatment process consists of coagulation/flocculation followed by gravity 

separation. The treated water is not filtered and contains concentrations of TSS, aluminum, 

antimony, and nickel. About 80-90% of Intalco’s process water discharge is non-contact cooling 

water. The concentration of these constituents in the PUD supply water is neither increased nor 

decreased by use of once-through non-contact cooling. The TSS and aluminum levels in the 

incoming source water do not meet the technology-based limits for primary aluminum smelters 

that are based upon the amount of product produced. 

Since the TSS, aluminum, antimony and nickel levels in the effluent at Outfall 001 are not fully 

representative of the impacts from the smelter, the NPDES permit allows Intalco to “net out” 

incoming pollutants in the intake water. Netting out allows Intalco to subtract the amount of 

Fact Sheet Page 21 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
TSS, aluminum, antimony and nickel in the intake water from the values in the effluent to 

determine compliance with effluent limits. The effluent limits established for Outfall 001 are for 

the net discharge of TSS, aluminum, antimony and nickel. 

Netting out is allowed in federal regulation, 40 CFR 122.45(g). There is a restriction that the 

discharge is to the same water body as the intake water unless there is a finding of no 

environmental degradation. Ecology policy uses the results of whole effluent toxicity (WET) 

tests as the criteria for determining environmental degradation. WET tests for Outfall 001 

indicate that no reasonable potential exists for acute or chronic receiving water toxicity. 

The permit will be reopened and the netting out provision for TSS, aluminum, antimony and 

nickel will be removed if any new information, such as the results of herring bioassay testing, 

shows that the receiving water environment is adversely affected by these constituents. 

STORMWATER ALLOCATION AT OUTFALL 001 

Condition S1.D of the permit requires Intalco to divert Outfall 002 stormwater to Outfall 001, 

pursuant to a specific time schedule. 

After completing the diversion of stormwater from Outfall 002 to Outfall 001, the effluent limits 

for Outfall 001 will be adjusted to allow an allocation for the following parameters in the 

additional flow: TSS, B(a)P, aluminum, and fluoride. The stormwater allocation for each of 

these parameters will be determined by converting the concentration-based limit for Outfall 002 

from the previous permit (1998) to a mass-based increment and adding it to the baseline effluent 

limit for Outfall 001. The additional stormwater flow from Outfall 002 entering Outfall 001 will 

be determined by continuous flow monitoring at D-10. 

The maximum daily stormwater allocation for fluoride was calculated as follows: 

Fa = Fc x flow x (3,785,000 l/million gallons)/(454,000 mg/lb) 

 

Fa = 416.9 x flow 

Where: 

Fa = Stormwater allocation for fluoride (lb/million gallons) 

Fc = Maximum daily concentration limit for fluoride in 1998 

 permit (50 mg/l) 

flow = Stormwater flow from Outfall 002 (millions of gallons/day) 

The same formula was used to calculate the average monthly stormwater allocation for 

fluoride and the stormwater allocations for TSS and aluminum. The stormwater 

allocation for B(a)P is based on the maximum stormwater B(a)P concentration measured 

in 20 months of Outfall 002 sampling. The allocations are tabulated below: 

Fact Sheet Page 22 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Stormwater Allocation 

(lbs/million gallons) 

Parameter Monthly 

Average 

Daily 

Maximum 

Total Suspended Solids 292 625 

Fluoride 292 417 

Aluminum 83 125 

B(a)P 0.0017 0.0017 

ELIMINATING THE TOTAL SUSPENDED SOLIDS (TSS) CONCENTRATION LIMIT 

FOR OUTFALL 001 

The previous permit contained two separate monthly average discharge limits for Total 

Suspended Solids (TSS) from Outfall 001: 

• 150 pounds/day (mass limit) 

• 10 milligrams/liter (concentration limit) 

During the permit renewal process, Intalco requested that the TSS concentration limit (10 mg/l) 

be eliminated from the new permit. Intalco believed that the mass limit was more stringent and 

thus protective of the receiving water. 

Over the term of the current permit (September 1998 through the present), Intalco has exceeded 

the daily maximum TSS limit on two occasions. The assignable causes for both of these 

exceedances were related to upsets in the operation of the facility’s secondary wastewater 

treatment plant. Intalco has never exceeded the monthly average TSS concentration limit or the 

monthly average TSS mass limit. 

At Ecology’s request, Intalco analyzed a database of over 1200 daily TSS measurements from 

the discharge. Intalco was able to show a correlation between TSS concentration and TSS mass 

discharges at Outfall 001. A monthly average discharge of TSS at a concentration of 10 mg/l is 

predicted to represent a mass discharge of 193 lb/day. Therefore, the 10 mg/l TSS concentration 

limit established in the current permit is less stringent than the 150 lb/day TSS mass limit. After 

reviewing Intalco’s analysis, Ecology agreed that the concentration limit is less stringent than the 

mass-based limit and eliminated it in the permit. 

Fact Sheet Page 23 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
REDUCED MONITORING FOR ANTIMONY, NICKEL, B(a)P, COPPER, CYANIDE, AND 

OIL AND GREASE 

According to 40 CFR 122.44(a)(2)(i), any limit that is based on federal effluent guidelines may 

not be removed from a permit unless the source of the pollutant has been completely eliminated 

and not just controlled. This rule allows a reduction in monitoring at appropriate levels. If the 

Permittee has demonstrated with adequate historic data that they can meet the permit limit then 

monitoring may be reduced to once per year (the minimum required under federal rules – 40 

CFR 122.44(i)(2). If the permit limit was based on BPJ and Ecology is convinced that the 

pollutant has no potential to cause environmental harm, the limit can be removed from the permit 

and replaced by reduced monitoring of the pollutant. 

In the permit, monitoring for B(a)P, antimony, nickel, copper, cyanide, and oil and grease at 

Outfall 001 and for copper, cyanide, B(a)P, and oil and grease at Outfall 002 have been reduced 

from the previous permit. See the discussion of production-based limits for B(a)P, antimony, 

and nickel in “TECHNOLOGY-BASED EFFLUENT LIMITATIONS” earlier in this 

document. See the discussion of the reduced monitoring for B(a)P, and antimony and nickel in 

“PERFORMANCE-BASED REDUCTION OF MONITORING FREQUENCIES” later in 

this document. The Permittee is required to monitor for copper as part of the annual priority 

pollutant scan (PPS) at both outfalls (Condition S1.I) and is required to monitor for cyanide as 

part of the annual PPS at Outfall 002. The monitoring frequency for O&G was reduced to 

monthly for both outfalls. These monitoring changes were made based on reviews of historical 

monitoring data and the fact that the sources of the respective pollutants have either been 

eliminated or are being controlled. The following paragraphs provide information about the 

Permittee’s management of the sources of B(a)P, copper, cyanide, and oil and grease. The 

limits for copper, cyanide, and oil and grease from the previous permit were not changed

B(a)P

Benzo-a-pyrene (B(a)P) is present in very small amounts in the coal tar pitch used in the 

manufacture of anodes for the reduction process. Several improvements in handling practices 

and treatment of wastewater have reduced the likelihood of B(a)P and other related polycyclic 

aromatic hydrocarbons (PAH) being released to the process or stormwater outfalls. The most 

significant source of B(a)P discharge to the process outfall is from anode contact cooling water. 

To mitigate this potential, a filtration system has been installed to augment the existing API 

separator. See the discussions of the anode contact cooling water under Outfall 001 in 

“Discharge Descriptions” above and in “Treatment Efficiency Studies” later in this document. 

In the past, there was a potential for contamination of stormwater with B(a)P because offspecification materials containing B(a)P were stored outside. These off-specification materials 

were diverted from the anode forming process when process upsets occurred and stored until 

they could be reused in the process. Recently, the areas where this temporary storage occurred 

have been covered and bermed to prevent stormwater from contacting this material and to 

prevent stormwater inside the berm from being released to the surrounding area. These materials 

are therefore no longer contributing to stormwater contamination. 

Fact Sheet Page 24 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Over the last permit term, 100% and 99% of the samples collected to monitor B(a)P in the 

discharges from Outfalls 001 and 002 respectively have been below the detection limit of 0.001 

mg/l. 

Copper

The source of copper in Intalco’s wastewater is believed to be from PUD intake water. Since the 

copper monitoring requirement was established in Intalco’s 1998 NPDES permit, 85% of the 

samples collected to monitor copper have had copper concentrations below the detection limit of 

6 micrograms/liter. To date, with the exception of 7 samples, all of the copper values for the 591 

other samples collected were less than 15 micrograms/liter. A summary of the copper 

monitoring data collected over the term of the previous NPDES permit (September 1998- 

October 2004) is provided in Appendix I. 

In October 2003, 5 samples from monitored discharges were found to contain copper 

concentrations above 250 micrograms/liter which were apparently false positives due to 

laboratory reagent water contamination. Monitoring results in December 2003 also indicated 

higher than normal copper concentrations. Intalco conducted an investigation of the root cause 

of these high copper concentrations. Intalco sampled several potential sources of contamination 

and analyzed them for traces of copper. The sources included the laboratory de-ionized water 

system, the acid supplies used for both preservation and digestion, and a representative sampling 

of volumetric glassware, and digestion vessels. Although the investigation did not conclusively 

find the source of the contamination, all of the aforementioned except the de-ionized water 

system were ruled out as potential sources of copper contamination. 

The samples collected from the de-ionized water system did not indicate copper contamination. 

However, inspection of the de-ionized water distribution discovered one faucet with a significant 

leak. When the valve system was removed and examined for damage, a badly corroded brass 

screw was found holding the washer onto the body of the valve stem. The screw was removed 

and replaced with a polypropylene screw. Subsequent analyses of the discharge samples for 

January through October 2004 show that the copper values have returned to the very low levels 

considered normal. 

Cyanide

The Permittee maintains a triple-lined landfill on site which is used for the disposal of spent 

potliner (SPL). This landfill has a leachate collection system and a containment berm in place. 

Cyanide is a component of the SPL in the landfill. A break in the triple liner or a breech in the 

containment berm could result in a potential discharge of cyanide to the stormwater system. 

A review of monthly discharge monitoring reports (DMR) back through January 1994 indicated 

that 100% of the stormwater samples collected at Outfall 002 and analyzed for cyanide were 

below the method detection limit of 0.005 mg/l. Given 10 years of data indicating that there has 

been no cyanide detected in the Outfall 002 discharge, Ecology decided to reduce cyanide 

monitoring from weekly to annually. 

Fact Sheet Page 25 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Oil and Grease

Intalco has made significant advances in source reduction or treatment of organic materials over 

the last ten years. The largest potential for oil contamination occurs in the cooling water used in 

the “Direct chill” or DC casting process. This water has the potential to become contaminated 

with oils used in the hydraulics of this process. All of the water used in the DC casting process 

is pumped to a cooling tower equipped with an oil flocculation and flotation process. The oil, if 

present, is then removed and disposed as a solid waste in an approved landfill. 

Additional measures have been taken to reduce oil and grease contamination from the facility. 

These measures include the installation of small treatment systems to serve steam-cleaning 

operations at the automotive, central maintenance, and annex maintenance shops. The treatment 

systems consist of a coalescing filter and sand filter to remove both oil and grease and suspended 

solids. The waste materials from theses filters are disposed as solid waste. 

Frequency distributions of the Permittee’s oil and grease (O&G) monitoring data collected from 

1991 through 2004 for Outfalls 001 and 002 are presented in Tables 1 and 2 below. The 

Practical Quantitation Limit (PQL) and the Method Detection Limit (MDL) for O&G were 3.0 

mg/L and 1.0 mg/L respectively. Based on a review of this data, Ecology reduced the monitoring 

frequency from daily to monthly for both Outfalls. 

Table 1 – Oil & Grease Monitoring Data for Outfall 001 

Concentration (mg/L) 

Range 

(Maximum Daily Permit 

Limit = 10 mg/L) 

Frequency of 

Occurrence 

% of Total Data in 

Concentration Range 

0-1 2995 60.29% 

1-2 1417 28.52% 

2-3 382 7.69% 

3-4 122 2.46% 

4-5 29 0.58% 

5-6 14 0.28% 

6-7 6 0.12% 

7-8 2 0.04% 

8-9 0 0.00% 

9-10 0 0.00% 

>10(1) 1 0.02% 1

Occurred on July 20, 1991

Fact Sheet Page 26 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Table 2 – Oil & Grease Monitoring Data for Outfall 002 

Concentration 

(mg/L) Range 

(Maximum Daily 

Permit Limit = 10 

mg/L) 

Frequency of 

Occurrence 

% of Total Data in 

Concentration Range 

0-1 2275 46.33% 

1-2 1613 32.85% 

2-3 625 12.73% 

3-4 250 5.09% 

4-5 89 1.81% 

5-6 28 0.57% 

6-7 14 0.29% 

7-8 14 0.29% 

8-9 2 0.04% 

9-10 0 0.00% 

>10 0 0.00% 

SURFACE WATER QUALITY-BASED EFFLUENT LIMITATIONS 

In order to protect existing water quality and preserve the designated beneficial uses of 

Washington's surface waters, WAC 173-201A-060 states that waste discharge permits shall be 

conditioned such that the discharge will meet established Surface Water Quality Standards. The 

Washington State Surface Water Quality Standards (Chapter 173-201A WAC) is a state 

regulation designed to protect the beneficial uses of the surface waters of the state. Surface 

water quality-based effluent limitations may be based on an individual waste load allocation 

(WLA) or on a WLA developed during a basin wide total maximum daily loading study 

(TMDL). 

NUMERICAL CRITERIA FOR THE PROTECTION OF AQUATIC LIFE

"Numerical" water quality criteria are numerical values set forth in the State of Washington's 

Water Quality Standards for Surface Waters (Chapter 173-201A WAC). They specify the levels 

of pollutants allowed in receiving water while remaining protective of aquatic life. Numerical 

criteria set forth in the Water Quality Standards are used along with chemical and physical data 

for the wastewater and receiving water to derive the effluent limits in the discharge permit. 

When surface water quality-based limits are more stringent or potentially more stringent than 

technology-based limitations, they must be used in a permit. 

NUMERICAL CRITERIA FOR THE PROTECTION OF HUMAN HEALTH 

The U.S. EPA has promulgated 91 numeric water quality criteria for the protection of human 

health that are applicable to Washington State (EPA 1992). These criteria are designed to protect 

humans from cancer and other disease and are primarily applicable to fish and shellfish 

consumption and drinking water from surface waters. 

Fact Sheet Page 27 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
NARRATIVE CRITERIA

In addition to numerical criteria, "narrative" water quality criteria (WAC 173-201A-030) limit 

toxic, radioactive, or deleterious material concentrations below those which have the potential to 

adversely affect characteristic water uses, cause acute or chronic toxicity to biota, impair 

aesthetic values, or adversely affect human health. Narrative criteria protect the specific 

beneficial uses of all fresh (WAC 173-201A-130) and marine (WAC 173-201A-140) waters in 

the State of Washington. 

ANTIDEGRADATION 

The State of Washington's Antidegradation Policy requires that discharges into a receiving water 

shall not further degrade the existing water quality of the water body. In cases where the natural 

conditions of a receiving water are of lower quality than the criteria assigned, the natural 

conditions shall constitute the water quality criteria. Similarly, when the natural conditions of a 

receiving water are of higher quality than the criteria assigned, the natural conditions shall be 

protected. More information on the State Antidegradation Policy can be obtained by referring to 

WAC 173-201A-070. 

Ecology has reviewed existing water quality data from Ecology’s long-term monitoring station 

GRG002 and from Eric Crecelius (2000). The data show that the ambient water meets the 

temperature, dissolved oxygen, pH, turbidity, ammonia, cyanide and metals standards for the 

designated Class AA marine waters given in Chapter 173-201A WAC. Therefore, will use the 

designated classification criteria for this water body in the permit. The discharges authorized by 

this permit should not cause a loss of beneficial uses. 

EFFLUENT QUALITY 

Pollutant concentrations of chlorine, copper, cyanide, and nickel in the proposed discharge from 

Outfall 001 exceed aquatic life water quality criteria at the point of discharge with technologybased controls that Ecology has determined to be AKART. Similarly, PAHs in the proposed 

discharge from Outfall 001 exceed the human health water quality criteria. Therefore, Ecology 

considered whether the discharge from Outfall 001 qualifies for a mixing zone in accordance 

with WAC 173-201A-400. 

Pollutant concentrations of copper, and nickel in the proposed discharge from Outfall 002 exceed 

aquatic life water quality criteria at the point of discharge with BMPs and technology-based 

controls that Ecology has determined to be AKART. Similarly, PAHs in the proposed discharge 

from Outfall 002 exceed the human health water quality criteria. Therefore, considered whether 

the discharge from 002 qualifies for a mixing zone in accordance with WAC 173-201A-400. 

DESCRIPTION OF THE RECEIVING WATER

The Permittee discharges to marine waters in the Strait of Georgia and these waters are 

designated waters of extraordinary quality in the vicinity of Outfalls 001, 002, 003-005, 011, and 

012. Characteristic uses include the following: fish migration; fish and shellfish rearing, 

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Intalco NPDES Permit (WA-000295-0) 
spawning and harvesting; wildlife habitat; primary contact recreation; sport fishing; boating and 

aesthetic enjoyment; commerce and navigation. Water quality of this class shall markedly and 

uniformly exceed the requirements for all or substantially all uses. 

The closest Ecology long-term core monitoring station, GRG002, is located in the Strait of 

Georgia near Patos Island. It is far enough away from the Cherry Point industries to prevent 

their discharges from influencing readings taken there. There is also substantial data for this 

station. The station at Bellingham Bay, BLL009, is also very close but is influenced by activity 

in Bellingham and is not suitable for a background data station. The closest long-term rotating 

station is LOP001 in Lopez Sound. 

SURFACE WATER QUALITY CRITERIA

Applicable criteria are defined in Chapter 173-201A WAC for aquatic biota. In addition, U.S. 

EPA has promulgated human health criteria for toxic pollutants (EPA 1992). Criteria for this 

discharge are summarized below: 

Fecal Coliforms 14 organisms/100 mL maximum geometric mean 

Dissolved Oxygen 7.0 mg/L minimum 

Temperature 13 degrees Celsius maximum or incremental increases above 

background 

pH 7.0 to 8.5 standard units 

Turbidity less than 5 NTU above background 

No toxics in toxic amounts (see Appendix L for numeric criteria 

for toxics of concern for this discharge) 

Toxics 

The Strait of Georgia is listed on the 2003/2004 Clean Water Act 303(d) list. It is listed for a 

variety of pollutants found in the sediments near Outfall 001. The following pollutants were 

found in the sediments around the Intalco discharge outfalls: hexachlorobenzene, bis(2-

ethylhexylphthalate), dibenzofuran, phenol, PCBs, and PAHs. 1,2,4-trichlorobenzene and 1,2-

dichlorobenzene were not detected but the detection limits for these parameters exceeded the 

Sediment Quality Standards. Stations near the Intalco discharge that have exceeded numeric 

sediment quality standards have passed confirmatory bioassay testing in accordance with the 

Sediment Management Standards (SMS) rule (Chapter 173-204 WAC). Under the SMS rule, 

sediments that pass confirmatory bioassays meet the sediment quality standards regardless of the 

numeric sediment chemistry results. 

Intalco is required to submit a Sediment Sampling and Analysis Plan in Condition S11.A. of the 

permit. The additional monitoring to recharacterize the sediment in the vicinity of Outfalls 001 

and 002 will be conducted during the beginning of the next permit cycle. 

Fact Sheet Page 29 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
MIXING ZONES

The Water Quality Standards allow Ecology to authorize mixing zones around a point of 

discharge. Both "acute" and "chronic" mixing zones may be authorized for pollutants that can 

have a toxic effect on the aquatic environment near the point of discharge. The concentration of 

pollutants at the boundary of these mixing zones may not exceed the numerical criteria for that 

type of zone. Mixing zones for toxicants can only be authorized for discharges that are receiving 

all known, available, and reasonable methods of prevention, control and treatment (AKART) and 

in accordance with other mixing zone requirements of WAC 173-201A-400. 

The National Toxics Rule (EPA, 1992) allows mixing zones to be used to meet human health 

criteria. Ecology has decided to use the chronic mixing zone for human health criteria. 

Ecology has established a compliance schedule in the permit to divert stormwater from the 

present discharge at Outfall 002 to Outfall 001. After the diversion is complete, Ecology will 

allow some stormwater to be discharged from Outfall 002 at times when the hydraulic capacity 

of Outfall 001 would be exceeded, a condition that is expected to occur very infrequently. The 

following discussion regarding Outfall 002 pertains to the mixing zone for stormwater both 

before and after the diversion. 

MIXING ZONE DETERMINATIONS FOR OUTFALLS 001 AND 002 

1. WAC 173-201A-400(1) requires that the allowable size and location of a mixing zone and 

associated effluent limits be established in a permit. 

This permit specifies the size and location of the allowable mixing zones for Outfalls 001 

and 002 and the associated effluent limits. 

2. WAC 173-201A-400(2) requires a discharger to fully apply AKART prior to being 

authorized a mixing zone. 

Ecology has determined that the treatment provided for the discharges at Outfalls 001 and 

002 and the pollution prevention activities practiced at Intalco meet the requirements of 

AKART. 

3. WAC 173-201A-400(3) requires mixing zone determinations to consider critical discharge 

conditions. 

Critical discharge conditions are those conditions that result in reduced dilution. Factors 

affecting dilution include the depth of water, the density stratification in the water 

column, the density of the effluent, the currents and the rate of discharge. The Permit 

Writer’s Manual provides guidance on how to derive the critical conditions for evaluating 

Fact Sheet Page 30 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
dilution from an outfall. Ecology followed that guidance in determining the acute, 

chronic, and human health criteria dilution factors. 

Critical flow conditions for Outfall 001 were re-evaluated for this permit to consider four 

different flow conditions, which the discharge could experience during the term of the 

permit. The conditions are: 

• Flows based on full production and non-contact cooling water (This is the existing 

condition) 

• Flows based on the addition of Outfall 002 stormwater to full production and noncontact cooling water. 

• Flows based on full production only with the non-contact cooling water removed 

(there are plans for a co-generation facility to be built by the BP refinery, which will 

use the non-contact cooling water). 

• Flows based on full production, no non-contact cooling water, and the addition of 

Outfall 002 stormwater. 

4. WAC 173-201A-400(4) states that no mixing zone shall be granted unless supporting 

information clearly indicates that the mixing zone would not have a reasonable potential to 

cause a loss of sensitive or important habitat, substantially interfere with the existing or 

characteristic uses of the water body, result in damage to the ecosystem, or adversely affect 

public health as determined by the department. 

The wastewater discharges at Outfalls 001 and 002 have been evaluated to determine if 

there is a reasonable potential to exceed water quality standards. Water quality standards 

are based on EPA criteria. EPA’s criteria were developed from toxicity tests with 

numerous organisms. Water quality standards include relevant durations of exposure and 

are not based on instantaneous exposures. 

Acute standards generally are based on a 1-hour exposure at the criteria level and chronic 

standards generally are based on a 4-day exposure at the criteria level. The dilution 

modeling under critical conditions showed that the acute dilution at Outfall 001 was 

attained in less than 1 minute and the chronic dilution in less than 9 minutes. The 

dilution modeling under critical conditions showed that the acute dilution at Outfall 002 

was attained in less than 3 minutes and the chronic dilution in less than 9 minutes. 

Drifting and non-strong swimming organisms in the water column would not be affected 

by Intalco’s discharge because they cannot physically stay in the plume close to the 

outfall long enough to be affected. Strong swimming fish could maintain a position 

within the plume, but they can also avoid it. 

Benthic organisms are not affected by the mixing zone because the plume is buoyant and 

rises in the water column. The diffuser for Outfall 001 itself is attached to pier pilings 

above the bottom which further prevents exposures to benthic organisms. 

Whole effluent toxicity (WET) testing provides a means of evaluating the cumulative 

toxicity of an effluent. WET testing performed by Intalco for Outfall 001 indicates that 

there is no reasonable potential for acute or chronic receiving water toxicity. During this 

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Intalco NPDES Permit (WA-000295-0) 
permit term, stormwater from Outfall 002 will be diverted to Outfall 001 and non-contact 

cooling water from the smelter is scheduled to be routed to the BP cogeneration facility 

for reuse. Non-contact cooling water will no longer be discharged via Outfall 001 if the 

BP cogeneration project is implemented. Consequently, Outfall 001 discharges will 

require additional WET characterization following these changes. 

Stormwater at Outfall 002 has occasionally shown toxicity at dilutions less than the 

chronic critical effluent concentration. Ongoing implementation and refinement of 

stormwater best management practices (BMPs) is effectively reducing stormwater 

toxicity. WET limits are set based on dilution factors. When stormwater is re-routed to 

Outfall 001, the increased mixing allowance will further reduce the potential for the 

stormwater to actually have toxic effects in the receiving water. 

The mixing zone for Outfall 001 is small and is centered at a distance of 1,100 feet from 

shore. The mixing zone does not overlap the herring spawning areas, which are closer to 

shore. The mixing zone for Outfall 002 is small and is centered at a distance of 250 feet 

from shore. When the stormwater is re-routed to Outfall 001, then the mixing zone for 

Outfall 002 will essentially be unused except for when the hydraulic capacity of Outfall 

001 is reached. This is likely to be a very rare occurrence and it is unlikely that these 

events would occur during the herring spawning season. 

There is no documented linkage between Intalco’s treated process water and stormwater 

effluents and the reduction in the local herring population. Intalco will use the recently 

developed herring bioassay tests to evaluate the possible effects of their effluents on 

herring and to compare the herring bioassay results with other EPA approved bioassay 

tests. 

When considering all of the above, Ecology has determined that the mixing zones for 

Outfalls 001 and 002 do not have a reasonable potential to cause a loss of sensitive or 

important habitat, substantially interfere with the existing or characteristic uses of the 

water body, result in damage to the ecosystem, or adversely affect public health. 

However, Ecology has determined that moving the stormwater discharge from Outfall 

002 to Outfall 001 is a reasonable, available, and prudent measure that will provide 

further protection for nearshore habitat. The very infrequent use of Outfall 002 after the 

diversion is complete should not result in harmful effects. 

5. WAC 173-201A-400(5) requires that water quality criteria shall not be violated outside of the 

boundary of a mixing zone. 

Ecology conducted a reasonable potential to exceed analysis for Outfalls 001 and 002 

(see Appendix L), using procedures established by EPA and Ecology, for each pollutant 

to assure that there will be no violations of the water quality criteria outside the boundary 

of the mixing zones. The RPTE analysis used the lowest dilution ratios from all of the 

mixing scenarios that were modeled. Modeling studies by ENSR in 2001 also evaluated 

the aggregate impact of the different industrial discharges in the Cherry Point area and 

documented that the combined discharges do not result in exceedances of water quality 

criteria. Whole effluent toxicity test results at Outfall 002 have also shown much 

improvement as adjustments and additions have been made to BMPs implemented by 

Intalco. 

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Intalco NPDES Permit (WA-000295-0) 
6. WAC 173-201A-400(6) requires that the size of a mixing zone and the concentrations of 

pollutants present shall be minimized. 

The mixing zone size constraints provided in WAC 173-201A-400(7) and (8) are among 

the most limiting in the country. At any given time, the effluent plume actually utilizes 

only a portion of the acute and chronic mixing zone, which effectively minimizes the 

volume of water actually involved in mixing. Because tidal currents change direction, 

the entire volume of the zone is needed to accommodate changes in plume orientation. 

The plume rises through the water column as it mixes and consequently most of the water 

volume in the mixing zone below the depth at which the mixed effluent traps, is not 

involved. Similarly, because the effluent will trap at some depth when density 

stratification is sufficient, waters above the trapping depth will also not be involved in the 

mixing. 

In the case of stormwater, much of the time the rate of discharge is much less than the 

rate that the allowed dilution is based on. That means that much of the time, the actual 

dilution will be greater, or that the allowed dilution will be realized closer to the outfall, 

in less time than under the critical conditions. 

It is impractical to attempt to specify in the permit the actual, more limited volume in 

which the dilution occurs as the plume rises, traps and moves with the current. However, 

the conservative modeled dilution factors implicitly reduce the mixing zone volume from 

the volume described in the permit to just the volume actually utilized by the plume. 

The size of the mixing zone (in the form of the dilution factor) has been minimized by the 

use of design criteria with low probability of occurrence. For example, the reasonable 

potential to exceed analysis used the expected 95th percentile pollutant concentration, the 

90th percentile background concentration, the flux average dilution factor, and the most 

restrictive ambient current relevant to the acute and chronic aquatic life and human health 

criteria. 

The chronic mixing zones for Outfalls 001 and 002 are small, extending 217 feet and 209 

feet, respectively, in all horizontal directions from the discharge points. The acute 

mixing zones are much smaller, extending 22 feet and 21 feet, respectively in all 

horizontal directions. When stormwater is re-routed to Outfall 001, the mixing zone for 

Outfall 002 will only be used during extreme storm events, and that is expected to be a 

rare occurrence. 

For all of the above reasons, the size of the mixing zones for Outfalls 001 and 002 and 

the concentrations of the pollutants present are appropriately and effectively minimized. 

7. WAC 173-201A-400(7)(b) and (8)(b) specify the sizing requirements for mixing zones in 

estuarine waters. 

The boundaries of the mixing zones were sized in accordance with the regulatory 

requirements. The chronic mixing zone for Outfall 001 extends 217 feet in all horizontal 

directions from the diffuser. The acute mixing zone for Outfall 001 extends 22 feet in 

any spatial direction from the diffuser. The chronic mixing zone extends 209 feet in all 

horizontal directions from Outfall 002. The acute mixing zone extends 21 feet in any 

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spatial direction from Outfall 002. The chronic mixing zones for each outfall extend 

from the seabed to the water surface. The human health mixing zones for each outfall are 

the same size as the chronic mixing zones. 

8. WAC 173-201A-400(8) requires that a zone where acute criteria may be exceeded is allowed 

only if it can be demonstrated to the department's satisfaction that the concentration of, and 

duration and frequency of exposure to the discharge, will not create a barrier to the migration 

or translocation of indigenous organisms to a degree that has the potential to cause damage to 

the ecosystem. 

The limited acute mixing zones authorized for Outfalls 001 and 002 will assure that they 

will not create a barrier to migration. The effluents from the two discharges will rise as 

they enter the receiving water assuring that they will not cause translocation of 

indigenous organisms. Dilution modeling has demonstrated that mixing in the acute 

zones occurs very rapidly as the less dense effluent rises through the water column due to 

both the diffuser design and the buoyancy of the effluent. Acute mixing occurs in less 

than a minute for Outfall 001 and in less than 3 minutes for Outfall 002 and the duration 

and frequency of exposure to elevated concentrations by any drifting or non-strong 

swimming organisms is minimized because the organisms simply cannot stay in one 

place while the plume moves past them. Because the mixing zone poses no barrier to 

organisms, strong swimming species are able to avoid the plume. Exposure to elevated 

concentrations in the effluents by benthic organisms is avoided because the plumes rise in 

the water column. 

The acute mixing zones are sized at 10% of the distance of the chronic mixing zones. 

Because the requirements of WAC 173-201A-400 have been satisfied, mixing zones are 

authorized in accordance with the following geometric configurations and dilution factors. 

9. WAC 173-201A-400(9) specifies conditions for allowing the overlap of mixing zones. 

The mixing zones for Outfalls 001 and 002 do not overlap with each other or with 

another mixing zone. 

DIFFUSER INFORMATION

The diffuser at Outfall 001 is approximately 120 feet long with a diameter of 24 inches. There 

are 12 ports on each side (north and south faces) of the diffuser. Each port is 6 inches in 

diameter. The average distance between each of the ports is 8 feet, 8 inches. The end of the 

diffuser has a blind flange with a 6 inch port in the center. The mean lower low water (MLLW) 

depth at the diffuser is 16 feet. 

Outfall 002 extends 250 feet from the shoreline. The open-ended pipe is 30 inches in diameter. 

The MLLW depth at the discharge point is 9 feet. 

This information and additional information is available in the report entitled “Outfalls 001 and 

002 Dilution Ratio Study” submitted to Ecology on December 1, 2006 (Cosmopolitan 

Engineering Group, 2006). 

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CHRONIC MIXING ZONES

WAC 173-201A-400(7)(b) specifies that mixing zones shall not extend in any horizontal 

direction from the discharge ports for a distance greater than 200 feet plus the depth of water 

over the discharge ports as measured during MLLW. Given a MLLW depth of 16 feet for the 

diffuser at Outfall 001, the horizontal distance is 216 feet. The mixing zone extends from the 

seabed to the top of the water surface. The horizontal distance of the chronic mixing zone at 

Outfall 002 is 209 feet. 

ACUTE MIXING ZONES

WAC 173-201A-400(8)(b) specifies that in estuarine waters a zone where acute criteria may be 

exceeded shall not extend beyond 10% of the distance established for the chronic zone. The 

acute mixing zone for Outfall 001 extends 22 feet in any spatial direction from any discharge 

port. The acute mixing zone for Outfall 002 extends 21 feet in any spatial direction from the 

discharge pipe. 

The dilution factors of effluent to receiving water that occur within these zones have been 

determined by the use of a dye study and modeling. The 1991 dye study, the 2002 and 2004 

modeling were re-analyzed in August 2006 and revised in November 2006. The report entitled 

“Outfalls 001 and 002 Dilution Ratio Study” was prepared by Cosmopolitan Engineering Group 

for Intalco. The models used for near field effects were the EPA dilution models DKHW and 

UM3. Far field effects were predicted using the EPA dilution model UM3. The dilution factors 

determined from this analysis are as follows: 

Full Production plus non-contact cooling water and separate stormwater 

outfall (current condition) 

Acute Chronic 

Aquatic Life Outfall 001 27 41 

 Outfall 002 5 33 

Human Health, Carcinogen 

 Outfall 001 NA 56 

 Outfall 002 NA 38 

Human Health, Non-carcinogen 

 Outfall 001 NA 53 

 Outfall 002 NA 38 

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Full Production plus non-contact cooling water plus stormwater 

(diverting Outfall 002 to Outfall 001)

Acute Chronic 

Aquatic Life Outfall 001 26 40 

Human Health, Carcinogen 

 Outfall 001 NA 54 

Human Health, Non-carcinogen 

 Outfall 001 NA 52 

Full production minus non-contact cooling water and separate 

stormwater outfall (sending cooling water to BP Cogen before the 

diversion is complete) 

Acute Chronic 

Aquatic Life Outfall 001 40 66 

 Outfall 002 5 33 

Human Health, Carcinogen 

 Outfall 001 NA 87 

 Outfall 002 NA 38 

Human Health, Non-carcinogen 

 Outfall 001 NA 87 

 Outfall 002 NA 38 

Full Production minus non-contact cooling water plus stormwater 

(diverting Outfall 002 to Outfall 001 and sending cooling water to BP 

Cogen) 

Acute Chronic 

Aquatic Life Outfall 001 28 61 

Human Health, Carcinogen 

 Outfall 001 NA 83 

Human Health, Non-carcinogen 

 Outfall 001 NA 83 

Additional information regarding the updated mixing zone analysis is shown in Appendix J. A 

complete record of the dilution analysis for the Intalco aluminum smelter is available in 

Ecology’s files. 

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Intalco NPDES Permit (WA-000295-0) 
CONSIDERATION OF SURFACE WATER QUALITY-BASED LIMITS FOR NUMERIC CRITERIA

Pollutant concentrations in the proposed discharges exceed water quality criteria with 

technology-based controls, which Ecology has determined to be AKART. A mixing zone is 

authorized for each discharge in accordance with the geometric configuration, flow restriction, 

and other restrictions for mixing zones in Chapter 173-201A WAC as described above. 

Pollutants in an effluent may affect the aquatic environment near the point of discharge (near 

field) or at a considerable distance from the point of discharge (far field). Toxic pollutants, for 

example, are near-field pollutants--their adverse effects diminish rapidly with mixing in the 

receiving water. Conversely, a pollutant such as BOD is a far-field pollutant whose adverse 

effect occurs away from the discharge even after dilution has occurred. Thus, the method of 

calculating surface water quality-based effluent limits varies with the point at which the pollutant 

has its maximum effect. 

The derivation of surface water quality-based limits also takes into account the variability of the 

pollutant concentrations in both the effluent and the receiving water. 

Surface water quality-based limits are derived for the water body's critical condition, which 

represents the receiving water and waste discharge condition with the highest potential for 

adverse impact on the aquatic biota, human health, and existing or characteristic water body 

uses. 

The critical condition for the Georgia Strait at Outfalls 001 and 002 occurs during the neap tide 

at MLLW and with 90th percentile background pollutant concentrations. Ambient data at critical 

conditions in the vicinity of the two outfalls was taken from both historical data at Ecology’s 

Ambient Monitoring Station GRG002 and an intensive monitoring study conducted in JulySeptember 1999 entitled “Concentration of Metals in Marine Water and Effluent of the Alcoa 

Intalco Works,” prepared by Eric Crecelius, Battelle Marine Sciences Laboratory, April 2000): 

Parameter Value Used 

Temperature 19.3o C 

pH (high) 7.9 

Dissolved Oxygen 8.0 mg/l 

Ammonia-N, total 0.45 mg/l 

Cyanide, total <0.01 mg/l 

Fluoride 1.27 mg/l 

Aluminum, dissolved 11.4 μg/l 

Cadmium, dissolved 0.11 μg/l 

Copper, dissolved 0.93 μg/l 

Lead, dissolved 0.02 μg/L 

Mercury 0.0012 μg/L 

Zinc, dissolved 2.90 μg/L 

Other Metals Below detection limits 

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The impacts of dissolved oxygen deficiency, temperature, pH, turbidity, ammonia, metals, and 

other toxics were determined as shown below, using the dilution factors at critical conditions 

described above. 

BOD5

This discharge results in a small amount of BOD loading relative to the large amount of dilution 

occurring in the receiving water at critical conditions. Technology-based limitations will be 

protective of dissolved oxygen criteria in the receiving water. 

Temperature

The impact of the discharges from Outfalls 001 and 002 on the temperature of the receiving 

water was analyzed using the guidance for the State’s new temperature standards, WAC 173-

201A-210. To determine the reasonable potential to exceed temperature standards, Ecology 

evaluated the following criteria: 

1. Annual Summer Maximum Criteria – Each water body has an annual maximum temperature 

criterion. These threshold criteria protect specific categories of aquatic life by controlling the 

effect of human actions on summer temperatures. The reasonable potential to exceed the annual 

summer maximum criteria for Outfalls 001 and 002 was determined by using the following 

equation: 

T chronic = T ambient90 + (T effluent95 - T ambient90)/DF 

Where: 

• T chronic = Receiving water temperature at the chronic mixing zone boundary 

• T ambient90 = 90th percentile of background temperatures at 

Station GRG002 from January 1999 through June 2005 

• T effluent95 = 95th percentile of daily maximum effluent temperatures from 

January 1999 through October 2006. 

• DF = Chronic dilution factor at the critical condition 

If T chronic is greater than the criterion of 13 oC for extraordinary quality receiving waters, an 

effluent limit is needed. 

Table 1 in Appendix K shows that the T chronic in all cases for both Outfalls 001 and 002 is less 

than the temperature criterion of 13 oC. Therefore, there is no predicted violation of Water 

Quality Standards and an effluent limit is not required. 

2. Incremental Warming Criteria – Where background temperatures are cooler than criterion - 

At locations and times when background temperatures are cooler than the assigned threshold 

criterion, point sources are permitted to warm the water at the edge of the mixing zone by only a 

defined increment t. The reasonable potential to exceed incremental warming criteria for 

Outfalls 001 and 002 was determined using the equations below: 

• T chronic = T ambient + (T effluent95 - T ambient)/DF 

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• t = 12/(T ambient – 2) 

Where: 

• T chronic = Receiving water temperature at the chronic mixing zone boundary 

• T ambient = Instantaneous maximum background temperature during critical 

time period at Station GRG002 from January 1999 through June 

2005 

• T effluent95 = 95th percentile of daily maximum effluent temperatures from 

January 1999 through October 2006 

• DF = Chronic dilution factor at the critical condition 

If the ambient background temperature (T ambient) is cooler than the threshold criterion, and if T 

chronic is greater than (T ambient + t), an effluent limit is needed.

Tables 2 and 3 in Appendix K show the reasonable potential to exceed evaluation for several 

ambient temperatures selected from the spring months (March-June) of 1999 through 2005. 

Outfalls 001 and 002 discharge into the Cherry Point area where the herring spawn during the 

spring season. Therefore, spring temperatures were chosen as the critical time period for this 

evaluation. 

In all cases, the T chronic for Outfalls 001 and 002 in Tables 2 and 3 is less than (T ambient + t). 

Therefore, there is no predicted violation of Water Quality Standards and an effluent limit is not 

required. 

3. Incremental Warming Criteria – When the criterion is exceeded due to natural conditions – At 

locations and times when a threshold criterion is being exceeded due to natural conditions, all 

human sources, considered cumulatively, must not warm the waterbody more than 0.3oC above 

the naturally warm condition. If the ambient temperature (expressed as the 90th percentile of 

background temperatures, T ambient90) is warmer than the threshold criterion, then an incremental 

warming analysis must be performed. 

The T ambient90 for the Strait of Georgia in the vicinity of Outfalls 001 and 002 is 11.8 oC, which 

is less than the threshold temperature criterion of 13 oC. Therefore, the incremental warming 

criteria is not applicable. 

pH

Because of the high buffering capacity of marine water, compliance with the technology-based 

effluent limits of 6.0 to 9.0 will assure compliance with the Water Quality Standards for Surface 

Waters. 

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Intalco NPDES Permit (WA-000295-0) 
Turbidity

The impact of turbidity was evaluated based on the range of turbidity in the effluent and turbidity 

of the receiving water. Due to the large degree of dilution, it was determined that the turbidity 

criteria would not be violated outside the designated mixing zone. 

Toxic Pollutants

Federal regulations (40 CFR 122.44) require NPDES permits to contain effluent limits for toxic 

chemicals in an effluent whenever there is a reasonable potential for those chemicals to exceed 

the surface water quality criteria. This process occurs concurrently with the derivation of 

technology-based effluent limits. Facilities with technology-based effluent limits defined in 

regulation are not exempted from meeting the Water Quality Standards for Surface Waters or 

from having surface water quality-based effluent limits. 

The following toxics were determined to be present in the discharge: ammonia, heavy metals, 

cyanide, phenols, and trace PAHs. A reasonable potential analysis (Appendix L) was conducted 

on these parameters to determine whether or not effluent limitations would be required in this 

permit. 

Valid ambient background data was available for ammonia, total cyanide, fluoride, aluminum, 

dissolved cadmium, dissolved copper, dissolved lead, mercury, and dissolved zinc. Calculations 

using all applicable data resulted in a determination that there is no reasonable potential for this 

discharge to cause a violation of water quality standards (See Appendix L). This determination 

assumes that the Permittee meets the other effluent limits of this permit. 

Water quality criteria for metals in Chapter 173-201A WAC are based on the dissolved fraction 

of the metal, except for arsenic and mercury. 

Metal criteria may also be adjusted using the water effects ratio approach established by USEPA, 

as generally guided by the procedures in USEPA Water Quality Standards Handbook, December 

1983, as supplemented or replaced. 

Ammonia

Ammonia is considered to be a toxic pollutant and was evaluated for reasonable potential to 

exceed water quality standards. Determining the site-specific acute and chronic criteria for 

ammonia is slightly more complicated than simply obtaining the criteria from the regulations and 

comparing them to the effluent data. Ammonia's toxicity is dependent on that portion which is 

available in the unionized form. The amount of unionized ammonia is dependent on the pH, 

salinity, and temperature of the receiving water in the marine environment. In order to evaluate 

ammonia toxicity, receiving water information must be used. 

One ambient receiving water station was evaluated to determine the site-specific acute and 

chronic criteria and to obtain background ammonia data. The Ecology ambient monitoring 

station GRG002 was used in this analysis. Acute and chronic ammonia criteria were calculated 

using Hampson's model in a spreadsheet form. From those criteria, the 90th percentile value was 

chosen to represent the critical condition as recommended by the Ecology Permit Writer's 

Manual. The values for the ambient station and the 90th percentile values for background total 

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ammonia concentrations were used in the reasonable potential calculation shown in Appendix L. 

With the available dilution, it was determined that there is no reasonable potential for Intalco to 

exceed water quality standards for ammonia at the edge of the dilution zone. 

WHOLE EFFLUENT TOXICITY

The Water Quality Standards for Surface Waters require that the effluent not cause toxic effects 

in the receiving waters. Many toxic pollutants cannot be detected by commonly available 

detection methods. However, toxicity can be measured directly by exposing living organisms to 

the wastewater in laboratory tests and measuring the response of the organisms. Toxicity tests 

measure the aggregate toxicity of the whole effluent, and therefore this approach is called whole 

effluent toxicity (WET) testing. Some WET tests measure acute toxicity and other WET tests 

measure chronic toxicity. 

Acute toxicity tests measure mortality as the significant response to the toxicity of the effluent. 

Dischargers who monitor their wastewater with acute toxicity tests are providing an indication of 

the potential lethal effect of the effluent to organisms in the receiving environment. 

Chronic toxicity tests measure various sublethal toxic responses such as retarded growth or 

reduced reproduction. Chronic toxicity tests often involve either a complete life cycle test of an 

organism with an extremely short life cycle or a partial life cycle test on a critical stage of one of 

a test organism's life cycles. Organism survival is also measured in some chronic toxicity tests. 

Accredited WET testing laboratories have the proper WET testing protocols, data requirements, 

and reporting format. Accredited laboratories are knowledgeable about WET testing and capable 

of calculating an NOEC, LC50, EC50, IC25, etc. All accredited labs have been provided the most 

recent version of Ecology’s Publication # WQ-R-95-80, Laboratory Guidance and Whole 

Effluent Toxicity Test Review Criteria which is referenced in the permit. Any Permittee 

interested in receiving a copy of this publication may call the Ecology Publications Distribution 

Center 360-407-7472 for a copy. Ecology recommends that Permittees send a copy of the acute 

and chronic toxicity sections of their permits to their laboratory of choice. 

The WET tests for Outfall 001 during effluent characterization indicate that no reasonable 

potential exists to cause receiving water acute or chronic toxicity (See Appendix M). The 

Permittee will not be given an acute or chronic limit for the current discharge configuration at 

Outfall 001. The permit requires Intalco to conduct new characterization testing of the combined 

effluent at Outfall 001 following the diversion of Outfall 002 and to retest the effluent again prior 

to application for permit renewal. This additional testing is to demonstrate that acute or chronic 

toxicity has not increased in the effluent. 

If the Permittee makes process or material changes which, in Ecology’s opinion, results in an 

increased potential for effluent toxicity, then Ecology may require additional effluent 

characterization in a regulatory order, by permit modification, or in the permit renewal. Toxicity 

is assumed to have increased if WET testing conducted for submission with a permit application 

fails to meet the performance standards in WAC 173-205-020, "whole effluent toxicity 

performance standard". The Permittee may demonstrate to Ecology that changes have not 

increased effluent toxicity by performing additional WET testing after the time the process or 

material changes have been made. 

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Acute toxicity of Outfall 002 was measured during compliance monitoring in the previous permit 

term (See Appendix M). On five occasions the acute toxicity was found to be at levels that, in 

accordance with WAC 173-205-050(2)(a), have a reasonable potential to cause receiving water 

toxicity. An acute toxicity limit is therefore required. The acute toxicity limit is no 

statistically significant difference in test organism survival between the acute critical effluent 

concentration (ACEC), 16.7% of the effluent, and the control. 

The acute toxicity limit is set relative to the zone of acute criteria exceedance (acute mixing 

zone) established in accordance with WAC 173-201A-400. The ACEC is the concentration of 

effluent existing at the boundary of the acute mixing zone during critical conditions. 

Monitoring for compliance with an acute toxicity limit is accomplished by conducting an acute 

toxicity test using a sample of effluent diluted to equal the ACEC and comparing test organism 

survival in the ACEC to survival in nontoxic control water. The Permittee is in compliance with 

the acute toxicity limit if there is no statistically significant difference in test organism survival 

between the ACEC and the control. 

Chronic toxicity of Outfall 002 was also measured during compliance monitoring in the previous 

permit term (See Appendix M). On ten occasions the chronic toxicity was found to be at levels 

that, in accordance with WAC 173-205-050(2)(a), have a reasonable potential to cause receiving 

water toxicity. A chronic toxicity limit is therefore required. The chronic toxicity limit is no 

statistically significant difference in test organism response between the chronic critical effluent 

concentration (CCEC), 3.0% of the effluent, and the control. 

The chronic toxicity limit is set relative to the mixing zone established in accordance with WAC 

173-201A-400. The CCEC is the concentration of effluent existing at the boundary of the 

mixing zone during critical conditions. 

Monitoring for compliance with a chronic toxicity limit is accomplished by conducting a chronic 

toxicity test using a sample of effluent diluted to equal the CCEC and comparing test organism 

response in the CCEC to organism response in nontoxic control water. The Permittee is in 

compliance with the chronic toxicity limit if there is no statistically significant difference in test 

organism response between the CCEC and the control. 

TOXICITY IDENTIFICATION/REDUCTION (TI/RE) 

In May 1999, the stormwater discharge from Outfall 002 failed the chronic toxicity testing 

(WET) required in Condition S3. of the previous permit. Intalco began additional chronic testing 

in June 1999 per the requirements of WAC 173-205. The additional chronic testing exhibited 

toxicity failures. The toxicity failures triggered Intalco’s permit requirement to submit a 

Toxicity Identification/Reduction Evaluation (TI/RE) Plan to Ecology for review and approval. 

The purpose of the TI/RE Plan was to evaluate and determine the source of the toxicity and to 

identify measures to eliminate or reduce the toxicity. 

The results of Intalco’s Toxicity Identification Evaluation (TIE) identified aluminum as the 

source of toxicity with complicating factors resulting from the presence of fluoride. 

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Intalco NPDES Permit (WA-000295-0) 
Intalco conducted an Initial Source Assessment Study in response to the TI/RE from January 

through March 2000. The objectives of the study were to: 1) measure the concentrations of total 

and soluble aluminum, fluoride, and total suspended solids (TSS) in stormwater runoff at various 

locations, 2) identify the areas that contain processes which are significant source contributors, 

3) determine which areas would benefit from source reduction strategies and/or stormwater 

treatment, and 4) identify additional sampling studies to better quantify specific source 

contributions. Intalco conducted a Refined Source Assessment from March 2000 through June 

2001 in response to the findings of the Initial Source Assessment. 

In response to the TI/RE, Intalco reviewed and revised their housekeeping best management 

practices (BMPs) starting in June 2000. The BMPs included increased routine sweeping, 

covering the dross and collector bar storage areas, and instituting annual wet and dry season 

inspections as described in Section 10 of Intalco’s Stormwater Pollution Prevention Plan. 

The final report submitted by Intalco in response to the TI/RE is titled “Proposed Stormwater 

Pond Outfall Changes”, dated October 14, 2003. In this report, Intalco proposed modifying the 

stormwater discharge outlet to divert stormwater through Outfall 001. Stormwater flows that 

exceed the hydraulic capacity of Outfall 001 would be discharged through Outfall 002. The 

Outfall 002 diversion is discussed in more detail later in this document. 

Ecology has reviewed and approved all of the documents related to the TI/RE. Condition S.9 of 

the previous permit required Intalco to implement the BMPs and source reduction methods that 

were proposed as a result of the TI/RE. The draft permit requires a number of new BMPs to 

further reduce pollutant loading in the stormwater. Ecology has determined that in addition to 

stormwater treatment, source control/source reduction through BMPs, the diversion of Outfall 

002 to Outfall 001 is AKART for the Intalco facility. Condition S.1.D of the permit requires 

Intalco to complete the diversion within two years of the effective date of the permit. Conditions 

S8. and S9. of the permit require Intalco to recharacterize the effluent from Outfall 001 for acute 

and chronic toxicity. These studies are scheduled to occur after the Outfall 002 diversion has 

been completed and is operational to evaluate the impacts of mixing the effluent from Outfall 

002 with effluent from Outfall 001. 

CHERRY POINT HERRING

Background Information

Ecology has been working with several stakeholders including other state agencies, area 

industries, and the tribes (the Cherry Point Technical Workgroup) to investigate the Cherry Point 

herring decline. Over the past six years, Ecology has worked with Western Washington 

University’s Shannon Point Marine Center (SPMC) to develop herring tests to evaluate effluent 

toxicity as a source of the decline in the Cherry Point herring and to evaluate risks from 

industrial discharges to other herring stocks. As a result of these efforts, SPMC developed three 

herring tests. These three tests are a 96-hour larval acute survival test, a 10-day embryo survival 

and normal development test, and a 10-day larval survival and growth test. SPMC and a 

commercial lab, Nautilus Environmental, conducted validation studies of the three herring tests 

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Intalco NPDES Permit (WA-000295-0) 
during the 2005 herring spawning season. A validation study determines if a lab can get a 

reasonably consistent answer each time a test is performed using the same toxicant. 

Both labs successfully validated the 96-hour larval acute survival test and the 10-day embryo 

survival and normal development test. In November 2005, Ecology approved the regulatory use 

of these tests. The labs could not completely validate the 10-day larval survival and growth test, 

but its partial success and the knowledge gained promise better performance next time. 

Ecology has identified a number of other herring studies that are important in building on the 

success of the herring test development. These studies included comparing the herring embryo 

and larval survival and growth tests with Environmental Protection Agency (EPA) tests, an 

ambient toxicity study, and a temperature tolerance study. These studies and a request for 

funding were proposed to the Cherry Point Technical Workgroup and several other parties in 

2004. No support was offered at that time. 

Following the announcement regarding the validation of the two herring tests and after review 

and comment on the permit requirements in Tesoro’s and Intalco’s proposed NPDES permits, 

several industries approached Ecology to discuss alternatives to including the validated herring 

tests in the NPDES permits. 

Ecology and the industries discussed further refinement of the larval survival and growth test, 

validation of this test, and comparisons of the survival and growth test and the embryo test to 

EPA tests. In order to provide an assessment on Cherry Point herring while perfecting the larval 

survival and growth test and conducting the EPA comparisons, Ecology proposed an ambient 

toxicity study and temperature tolerance study. Industry agreed to support these studies in lieu of 

herring studies being included in this NPDES permit term. 

Agreed Order

Ecology has issued an agreed order with the BP Cherry Point Refinery, ConocoPhillips Ferndale 

Refinery, Shell Puget Sound Refinery, Tesoro Anacortes Refinery, and the Alcoa-Intalco Works 

Aluminum Smelter (Industries) to conduct additional herring research and studies. 

The Agreed Order (No. 3192) requires the five industries to conduct larval acute survival tests 

twice annually at each of their process wastewater and stormwater outfalls and to provide 

$227,000 in funding toward: 1) further refinement and validation of the larval survival and growth

test, 2) comparisons of herring test sensitivity to surrogate EPA tests, 3) an evaluation of ambient 

water toxicity at Cherry Point, 4) a temperature tolerance study of embryos from Cherry Point and 

two other regional herring stocks, and 5) to ensure a supply of herring gonads for use in these 

studies. 

The Order also includes a requirement to follow up on adverse effects found during the course of 

these studies with additional testing and/or investigation. Ecology will review the results of the 

studies required under the Order and include validated herring or equivalent EPA surrogate test 

requirements in the industry National Pollutant Discharge Elimination System (NPDES) permits 

during the next permit cycle. 

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Intalco NPDES Permit (WA-000295-0) 
Additional Benefits

After further refinement, the larval survival and growth test may be validated and approved for 

regulatory use. This will provide another tool for evaluating chronic effects on herring from 

effluent toxicity and expand the number of available commercial labs that can perform the test. 

Assuming that the EPA tests are equally or more sensitive than the herring tests, the EPA tests 

are better for monitoring effluents. The species used in the EPA tests are available year round, 

the tests can be performed more easily, and they are more economical. 

The ambient toxicity test will help Ecology to evaluate the combined effects of industry effluent 

plumes on herring embryos. Herring embryos are sensitive to high water temperatures. The 

temperature tolerance study will help Ecology to determine if water temperatures measured at 

Cherry Point are high enough to cause adverse effects on herring embryos. 

Herring Toxicity Testing Requirements for Intalco

Under the Agreed Order, Intalco will conduct herring larval toxicity testing on the final effluent 

from Outfall 001 twice a year beginning in January 2007. Intalco shall also conduct herring 

larval toxicity testing on the effluent from their stormwater outfall (002) twice a year beginning 

in January 2009, if the diversion to Outfall 001 has not occurred. 

HUMAN HEALTH

Washington’s water quality standards now include 91 numeric health-based criteria that must be 

considered in NPDES permits. These criteria were promulgated for the state by the U.S. EPA in 

its National Toxics Rule (Federal Register, Volume 57, No. 246, Tuesday, December 22, 1992). 

Ecology has determined that the Permittee’s effluent is likely to have chemicals of concern for 

human health. The Permittee's high priority status is based on its status as a major discharger 

and knowledge of data or process information indicating that regulated chemicals occur in the 

discharges from the facility. 

A determination of the discharge's potential to cause an exceedance of the water quality 

standards was conducted as required by 40 CFR 122.44(d) for Outfalls 001 and 002. The 

reasonable potential determination was evaluated following procedures in the Technical Support 

Document for Water Quality-Based Toxics Control (EPA/505/2-90-001) and Ecology’s Permit 

Writer's Manual (Ecology Publication 92-109, July, 1994). The determination indicated that the 

discharges from Outfalls 001 and 002 have no reasonable potential to cause a violation of water 

quality standards, thus an effluent limit is not warranted. See Appendix L. 

Arsenic

In 1992 the USEPA adopted risk-based arsenic criteria for the protection of human health for the 

State of Washington. The criterion for marine waters is 0.14 μg/L inorganic arsenic, and is 

based on exposure from fish and shellfish tissue ingestion. The freshwater criterion is 0.018 

μg/L, and is based on exposure from fish and shellfish tissue and water ingestion. These criteria 

have caused confusion in implementation because they differ from the drinking water maximum 

contaminant level (MCL) of 10 μg/L, which is not risk-based, and because the human health 

Fact Sheet Page 45 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
criteria are sometimes exceeded by natural background concentrations of arsenic in surface water 

and ground water. 

In Washington, when a natural background concentration exceeds the criterion, the natural 

background concentration becomes the criterion, and no dilution zone is allowed. This could 

result in a situation where natural groundwater or surface water used as a municipal or industrial 

source-water would need additional treatment to meet numeric effluent limits even though no 

arsenic was added as waste. Although this is not the case for all dischargers, we do not have data 

at this time to quantify the extent of the problem. 

A regulatory mechanism to deal with the issues associated with natural background 

concentrations of arsenic in groundwater-derived drinking waters is currently lacking. 

Consequently, the Water Quality Program, at this time, has decided to use a three-pronged 

strategy to address the issues associated with the arsenic criteria. The three strategy elements 

are: 

1. Pursue, at the national level, a solution to the regulatory issue of groundwater sources 

with high arsenic concentrations causing municipal treatment plant effluent to exceed 

criteria. The revision of the drinking water MCL for arsenic offered a national opportunity to 

discuss how drinking water sources can affect NPDES wastewater dischargers, however Ecology 

was unsuccessful in focusing the discussion on developing a national policy for arsenic 

regulation that acknowledges the risks and costs associated with management of the public 

exposure to natural background concentrations of arsenic through water sources. The current 

arsenic MCL of 10 μg/L could also result in municipal treatment plants being unable to meet 

criteria-based effluent limits. Ecology will continue to pursue this issue as opportunities arise. 

2. Additional and more focused data collection. The Water Quality Program will in some 

cases require additional and more focused arsenic data collection, will encourage or require 

dischargers to test for source water arsenic concentrations, and will pursue development of a 

proposal to have Ecology's Environmental Assessment Program conduct drinking water source 

monitoring as well as some additional ambient monitoring data. At this time, Washington 

NPDES permits will contain numeric effluent limits for arsenic based only on treatment 

technology and aquatic life protection as appropriate. 

3. Data sharing. Ecology will share data with USEPA as they work to develop new risk-based 

criteria for arsenic and as they develop a strategy to regulate arsenic. 

SEDIMENT QUALITY

Ecology has promulgated aquatic sediment standards (Chapter 173-204 WAC) to protect aquatic 

biota and human health. These standards state that Ecology may require Permittees to evaluate 

the potential for the discharge to cause a violation of applicable standards (WAC 173-204-400). 

In September 1999, Intalco conducted a marine sediment sampling and analysis study. The 

purpose of the Fall 1999 study was to 1) comply with the current NPDES permit sediment 

monitoring requirements, 2) determine if sediment remedial actions were necessary, and 3) 

evaluate sediment quality concerns related to the Department of Natural Resources (DNR) lease 

Fact Sheet Page 46 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
requirements. To meet these objectives, the study focused on: characterizing chemicals of 

potential concern (COC), concentrations and biological effects within and adjacent to the 

NPDES outfall mixing zones, analyzing facility process indicator chemicals including aluminum, 

fluoride, and cyanide, and analyzing select samples for the full suite of Sediment Management 

Standard (SMS) chemicals. 

Sediment was collected and analyzed from depths of 2 cm and 10 cm in order to assess sediment 

quality in the areas of ongoing discharge and in the biologically active zone, respectively. COCs 

were determined to be LPAHs, HPAHs, PCBs, and various semi-volatile organic compounds. 

The full suite of SMS chemicals were analyzed at stations in areas that had not been previously 

characterized. 

The sediment sampling found Sediment Quality Standard (SQS) and cleanup screening level 

(CSL) exceedances of both PCBs and PAHs in the upper 2 cm and the upper 10 cm of sediment. 

Other chemical exceedances included bis(2-ethylhexylphthalate), dibenzofuran, and phenol. 

The aluminum, fluoride, and phenol concentrations in the sediment were found to be equivalent 

to those found in reference samples collected in the Carr Inlet. The levels of phenols are 

believed to be due to the decomposition of coniferous wastes. Cyanide was not detected in any 

of the sediments collected during the investigation. The detection of chemicals that exceeded 

SQS chemical criteria was consistent with historical sampling data. 

Confirmatory bioassays were performed on the upper 10 cm of samples that exceeded the SQS 

chemical criteria. No adverse biological effects were found in any of the sediment samples 

indicating that elevated chemical concentrations in sediments adjacent to the Intalco facility were 

not associated with adverse ecological effects. Under WAC 173-204-310(2), sediment samples 

that pass all of the confirmatory biological tests are considered to pass sediment quality standards 

despite any exceedances of chemical standards. 

After a review of the chemistry and bioassay data collected during the 1999 study, Ecology 

agreed that remedial cleanup action of the sediments adjacent to Intalco is not necessary. 

However, chemical exceedances in surface sediments remain a concern. Chemical exceedances 

in the upper 10 cm near the process and stormwater outfalls may represent effects from the 

current discharges or another continuing source and need further investigation. Condition S11. 

of the permit includes a requirement to submit a Sediment Sampling and Analyses plan to 

conduct additional sediment sampling and analysis for PAHs, PCBs, aluminum, fluoride, and 

cyanide. The sediment recharacterization will be required early in the next permit term to 

evaluate sediment condition following the clean-up and closure of the Beach and Construction 

Landfills as discussed later in this document. 

FUGITIVE ALUMINA IMPACT STUDY

Concerns have been raised about the spillage of alumina ore during ship unloading and its 

possible accumulation in sediments around Intalco’s marine terminal. In December 1999, 

Intalco submitted a notice of construction application requesting approval to upgrade their 

alumina ore unloading air pollution control system. Ecology reviewed the application and issued 

an order of approval to upgrade the control system. After the approval order was issued, Intalco 

Fact Sheet Page 47 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
determined that their pier was not structurally able to accommodate the proposed upgrades and 

the upgrades were not installed. 

Since Intalco determined that the control system could not be upgraded, Intalco has made a 

considerable investment of resources into upgrading and maintaining the integrity of the seal on 

the clamshell and into operating the clamshell to minimize fugitive emissions. Intalco has also 

implemented a number of BMPs to minimize the fugitive emissions. Currently most of the 

alumina ore fugitive emissions are generated as the clamshell is lifted out of the ships hold. 

Based on the evaluations that have been made and the results of the BMPs that have been 

implemented, it is not likely that Intalco will be able to further reduce or eliminate alumina ore 

fugitive emissions. 

Ecology is planning to issue an order by mid-2007 under their air and water quality authorities 

that will require Intalco to evaluate the potential impact of fugitive emissions from alumina ore 

unloading on sediments near the Intalco pier. If the evaluation determines that there is a 

significant impact to sediments, Ecology will require Intalco to propose a method(s) to mitigate 

that impact. 

GROUND WATER QUALITY LIMITATIONS

Ecology has promulgated Ground Water Quality Standards (Chapter 173-200 WAC) to protect 

beneficial uses of ground water. Permits issued by Ecology shall be conditioned in such a 

manner so as not to allow violations of those standards (WAC 173-200-100). 

The stormwater pond is lined with a PVC liner. The sanitary lagoon in Intalco’s wastewater 

treatment system consists of an unlined native clay bottom that could potentially discharge to 

ground water. 

There is no data available to determine if there is a potential for an impact to ground water 

beneath the sanitary lagoon. As a result Intalco will be required to submit a ground water impact 

study plan to be implemented in the third and fourth year of the permit. The plan must include 

sampling and testing schedules for the sanitary lagoon for all of the parameters included in the 

groundwater quality standards (GWQS) (except pesticides, radionuclides, PBBs and dioxin), and 

a hydrogeologic investigation to estimate the impact to ground water. If this study determines 

that there is a potential for the wastewater in the sanitary lagoon to cause an exceedance of the 

GWQS, Intalco will be required to install monitoring wells to investigate any actual effects on 

the ground water. 

Fact Sheet Page 48 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
COMPARISON OF EFFLUENT LIMITS WITH THE EXISTING PERMIT ISSUED ON 

SEPTEMBER 1, 1998

Effluent Limitations: Outfall # 001 

Parameter Units Existing Permit New Permit 

Monthly 

Average 

Daily 

Maximum

Monthly 

Average

Daily 

Maximum

Total 

Suspended 

Solids

lbs/day 

mg/l 

150 

10 

185 

-- 

150 

-- 

185 

-- 

Fluoride lbs/day 68 296 68 296 

Aluminum lbs/day 10.3 30 10.3 30 

Free Cyanide mg/l <0.012 0.012 <0.012 0.012 

Benzo(a)Pyrene mg/l <0.01 0.01 

0.03 a/0.06 b 

(lb/day) 

0.065 a/0.13 b 

(lb/day) 

Antimony mg/l NLc NLc 2.85 a

/5.7 b 

(lb/day) 

6.4 a/12.8 b 

(lb/day) 

Nickel mg/l NLc NLc 1.25 a

/2.5 b 

(lb/day) 

1.85 a/3.7 b 

(lb/day) 

Oil and Grease mg/l 5 10 5 10 

pH Within the range of 6.0 - 9.0 Within the range of 6.0 - 9.0 a

 Permit Limit when aluminum production is less than or equal to 15,614 tons per month 

b

 Permit Limit when aluminum production is greater than 15,614 tons per month 

c NL= No Limit 

Effluent Limitations: Outfall # 002 

Parameter Units Existing Permit New permit 

Monthly 

Average 

Daily 

Maximum

Monthly 

Average

Daily 

Maximum

Total 

Suspended 

Solids

mg/l 35 75 35 75 

Fluoride mg/l 35 50 35 50 

Aluminum mg/l 10 15 10 15 

Fact Sheet Page 49 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Effluent Limitations: Outfall # 002 

Free Cyanide mg/l -- -- -- -- 

Benzo(a)Pyrene mg/l -- <0.01 -- <0.01 

Oil and Grease mg/l 5 10 5 10 

pH Within the range of 6.0 - 9.0 Within the range of 6.0 - 9.0 

Effluent Limitations: Sanitary Lagoon 

Existing Permit New permit 

Parameter Units 30-Day 

Average 

7-Day 

Average

30-Day 

Average

7-Day 

Average

Biochemical 

Oxygen Demand

mg/l 

lbs/day 

45.0 

22.4 

65.0 

32.4 

45.0 

22.4 

65.0 

32.4 

Total Suspended 

Solids

mg/l 

lbs/day 

45.0 

22.4 

65.0 

32.4 

45.0 

22.4 

65.0 

32.4 

Fecal Coliform Colonies/100 

ml 200 400 200 400 

Chlorine mg/l <0.012 0.012 -- -- 

Minimum Number 

of Operating 

Tubes

-- 12 

pH Within the range of 6.0 - 9.0 Within the range of 6.0 - 9.0

MONITORING REQUIREMENTS 

Monitoring, recording, and reporting are required (WAC 173-220-210 and 40 CFR 122.41) to 

verify that the treatment process is functioning correctly and the effluent limitations are being 

achieved. 

The monitoring schedule is detailed in the permit under Condition S1. Specified monitoring 

frequencies take into account the quantity and variability of the discharge, the treatment method, 

past compliance, significance of pollutants, and cost of monitoring. 

Fact Sheet Page 50 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
PERFORMANCE-BASED REDUCTION OF MONITORING FREQUENCIES 

EPA published guidance in April of 1996 entitled, “Interim Guidance for Performance-Based 

Reduction of NPDES Permit Monitoring Frequencies”. EPA’s goal is to reduce the regulatory 

burden associated with reporting and monitoring on the basis of excellent performance. The 

guidance recommends looking at and comparing long term average values to permit limits to 

evaluate a facility’s performance. 

Several parameters in Intalco’s treated effluent were evaluated using this guidance. In addition 

to using the approach recommended in the guidance, daily maximum values were also compared 

with permit limits. Appendix O summarizes the current and proposed monitoring frequencies 

based on two years of representative monitoring data (January 2000 – December 2002). 

 For the parameters evaluated, Intalco’s monitoring history has demonstrated an ability to 

consistently meet regulatory limits and knowledge of the treatment system operation. The 

proposed monitoring frequencies are based on the guidance recommendations and best 

professional judgment. 

Ecology deviated from the policy recommendations for fluoride and cyanide at Outfall 001 and 

fluoride and aluminum at Outfall 002 by increasing monitoring upstream at the secondary 

treatment plant and the stormwater pond. The monitoring frequencies for antimony and nickel, 

copper, and oil and grease at Outfall 001 and copper, cyanide, B(a)P, and oil and grease at 

Outfall 002 were further reduced because years of monitoring data and other plant knowledge 

have shown that the sources of these pollutants either no longer exist or have been controlled. 

More detailed information about these specific pollutants is discussed earlier in this document. 

B(a)P

Intalco conducted weekly B(a)P monitoring of Outfall 001 from April 1991 through September 

1998 and monthly monitoring since October 1998. The Outfall 001 data indicates that B(a)P 

concentrations have not been above the detection limit (0.001 mg/L) since February 1996. Prior 

to that, there were 10 occasions (between June 1995 and February 1996) when B(a)P was above 

the detection level (the highest level of B(a)P of those 10 occasions was 0.016 lb/day). Using the 

maximum water flow at Outfall 001 (3.5 million gallons per day), the 0.001 mg/L concentration 

translates to a long term average (LTA) of 0.03 lb/day, which is 100% of the proposed monthly 

average permit limit (0.03 lb/day when production is less than or equal to 15,614 tons per month) 

and 50% of the proposed monthly average permit limit (0.06 lb/day when production is greater 

than 15,614 tons per month). The highest level (0.016 lb/day) reported is 25% of the proposed 

daily maximum permit limit (0.065 lb/day when production is less than or equal to 15,614 tons 

per month) and 12% of the proposed daily maximum permit limit (0.13 lb/day when production 

is greater than 15,614 tons per month). 

Ecology determined a monitoring frequency of once per month and once per quarter at Outfall 

001 for B(a)P based on the previous monitoring frequency (once per month) and the ratio of the 

LTA to the proposed monthly average permit limits for both tiers as outlined in EPA's "Interim 

Guidance for Performance-Based Reduction of NPDES Permit Monitoring Frequencies" dated 

April 1996 (EPA’s Guidance). In EPA’s Guidance, the 100% ratio of LTA to the proposed 

monthly average limit for B(a)P when production is less than or equal to 15,614 tons per month 

requires monitoring once per month. The 50% ratio of LTA to the proposed monthly average 

Fact Sheet Page 51 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
limit for B(a)P when production is greater than 15,614 tons per month requires monitoring once 

per quarter. Because there have been no incidents of B(a)P reported above the detection level of 

0.0001 mg/l since March 2005, Ecology determined that requiring monitoring once per quarter is 

appropriate. 

Antimony and Nickel

As discussed earlier in “TECHNOLOGY-BASED EFFLUENT LIMITATIONS”, Ecology 

added mass-based limits (at Outfall 001) for antimony and nickel to this permit. Ecology 

reviewed the historical antimony and nickel data collected from 1988-1998 at Outfall 001. The 

table below provides a frequency distribution of that data. The data indicates that a significant 

amount of the total nickel and antimony in the effluent comes into the plant in the water supplied 

by the Public Utility District. The LTA of antimony (0.206 lb/day) is 7% of the proposed 

monthly average permit limit (2.85 lb/day when production is less than or equal to 15,614 tons 

per month) and 4% of the proposed monthly average permit limit (5.7 lb/day when production is 

greater than 15,614 tons per month). The highest level reported (0.375 lb/day) is 6% of the 

proposed daily maximum permit limit (6.4 lb/day when production is less than or equal to 15,614 

tons per month) and 3% of the proposed daily maximum permit limit (12.8 lb/day when 

production is greater than 15,614 tons per month). 

The LTA of nickel (0.198 lb/day) is 16% of the proposed monthly average permit limit (1.25 

lb/day when production is less than or equal to 15,614 tons per month) and 8% of the proposed 

monthly average permit limit (2.5 lb/day when production is greater than 15,614 tons per 

month). The highest level reported (0.646 lb/day) is 35% of the proposed daily maximum permit 

limit (1.85 lb/day when production is less than or equal to 15,614 tons per month) and 17% of 

the proposed daily maximum permit limit (3.7 lb/day when production is greater than 15,614 

tons per month). In the last 2 years of data collection (1997 and 1998), the highest level of 

nickel reported (0.256 lb/day) is 14% of the proposed daily maximum permit limit. 

Ecology determined a monitoring frequency of once every 6 months for antimony and nickel 

based on the previous monitoring frequency (once per month in the permit cycles during 1988-

1998 - summarized in the table below) and the ratio of the LTAs to the monthly average permit 

limits (<25%) as outlined in EPA's Guidance. 

Frequency Distribution of Antimony and Nickel Daily Mass Discharge 

Data (1988-1998)

Metal 

Concentration 

Range 

Effluent 

Nickel 

Influent 

Nickel 

Effluent 

Antimony 

Influent 

Antimony 

0.0-0.2 lb/day 174 195 121 50 

0.2-0.4 lb/day 88 87 159 236 

0.4-0.6 lb/day 14 4 0 0 

0.6-0.8 lb/day 4 0 0 0 

0.8-1.0 lb/day 0 0 0 0 

Fact Sheet Page 52 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
ACTION LEVELS FOR POLLUTANTS DISCHARGED FROM THE STORMWATER 

POND AND THE SECONDARY WASTEWATER TREATMENT SYSTEM 

Ecology established “action levels” in the permit for TSS, fluoride, and aluminum discharged in 

the stormwater pond (SWP) effluent and for TSS and fluoride discharged in the Secondary 

Wastewater Treatment System effluent. These action levels were placed in the permit to ensure 

that the Permittee is consistently implementing the required BMPs designed to reduce or 

eliminate the respective pollutants, evaluating the cause of any upward trends in pollutant 

discharges, and taking corrective action to reverse those trends. Ecology determined the action 

levels for the SWP and the SWTS based on an analysis of the 2003 and 2004 monthly 

monitoring data submitted by the Permittee in their discharge monitoring reports (DMRs). 

When action levels are exceeded at the SWP, the Permittee must review BMPs, check for spills 

to the stormwater system, and check ditches and weir integrity and placement. When action 

levels are exceeded at the SWTS, the Permittee must review BMPs, check addition rates of 

treatment chemicals, and influent flows and loading. 

LANDFILL MONITORING 

Intalco signed an Agreed Order with Ecology for the remedial investigation and feasibility study 

of three historic landfills on its property in Ferndale, Washington under the Model Toxics 

Control Act (MTCA). The three landfills -- known as Beach One, Beach Two, and the 

Construction Debris Landfill -- were used from 1965 until the 1970s and early 1980s to dispose 

of industrial solid waste generated at the Intalco plant. The landfills are located on bluffs above 

the Straight of Georgia. 

The Agreed Order required Intalco to determine the volume and type of material found in each 

landfill and to characterize any surface or ground water contamination from the landfills. This 

information was used as the basis for evaluating the different cleanup methods that were most 

appropriate for the site. The cleanup plan for the site was to remove the debris from the two 

Beach Landfills on the bluffs and place it in the permitted hazardous and solid waste landfill 

(Spent Potliner (SPL) Landfill) on the Intalco property and to close and cap the Construction 

Debris Landfill in place. The landfills were cleaned up and closed in the summer and fall of 

2006 under a Consent Decree issued by Ecology. 

Intalco stopped using the landfills in 1984 and closed them by placing soil covers over the 

debris. Intalco has been monitoring seeps located in the hillside below the closed landfills since 

1985. While there has been no determination of an immediate threat to human health or the 

environment from contaminants leaving the site, in November 1999, tests at three landfill 

monitoring stations (Outfalls 003, 004, and 005) indicated contaminants from the landfills may 

be leaching into surface water runoff. 

The results of the November 1999 monitoring as compared to current stormwater limits and the 

marine water quality standards are shown in Appendix N. The majority of the results exceed 

both stormwater limits and surface water quality standards. 

Fact Sheet Page 53 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
Intalco excavated and removed all waste materials and contaminated native soils from the Beach 

I and Beach II Landfills and installed an impermeable cap on the Closed Construction Debris 

Landfill. Ecology determined that this aggressive source control is AKART for the discharges 

from Outfalls 003, 004, and 005. Additional monitoring of these discharges will be conducted in 

accordance with the Consent Decree issued by Ecology. 

The NPDES permit includes new monitoring requirements at the Secondary Treatment Plant to 

test for PCBs and priority pollutant metals in the leachate from the SPL Landfill. Groundwater 

monitoring is required in the consent decree as part of the MTCA cleanup to evaluate impacts to 

groundwater from the closed landfills. 

STORMWATER POND MONITORING 

Condition S1.C of the permit requires Intalco to monitor the stormwater pond effluent whenever 

the average 2-hour flow from the stormwater pond is >3.7cfs (with a maximum required 

frequency of 3 days per week). Intalco determined, based on the results of their Stormwater 

Pond Characterization Study, that the minimum rainfall that occurs before significant flow 

begins at compliance point D-10 is about 0.05 inches of rainfall or 0.20 million gallons, which is 

one-tenth of the design storm volume. A volume of 0.20 million gallons is equal to a 3.7 cfs 

flow rate over a two hour time interval. After evaluating Intalco’s precipitation data for January 

2002 through September 2004, Ecology determined that a stormwater pond monitoring 

frequency based on the threshold volume of 3.7 cfs would be sufficient. 

Intalco will be expected to maintain historic performance levels to continue to receive the 

reduced monitoring. If the performance levels of the facility deteriorate, monitoring frequencies 

will revert to the frequencies in the current permit. 

EFFLUENT LIMITS BELOW QUANTITATION 

The water quality-based effluent limits for cyanide in the wastewater are below the capability of 

current analytical technology to quantify. The Quantitation Level is the level at which 

concentrations can be reliably reported with a specified level of error. For maximum daily 

effluent limits, if the measured effluent concentration is below the Quantitation Level, the 

Permittee reports NQ for non-quantifiable. For average monthly effluent limits, all effluent 

concentrations below the Quantitation Level but above the Method Detection Level are used as 

reported for calculating the average monthly value. 

EFFLUENT LIMITS BELOW DETECTION 

The Method Detection Level (MDL) is the minimum concentration of an analyte that can be 

measured and reported with a 99 percent confidence that its concentration is greater than zero as 

determined by a specific laboratory method. For maximum daily limits, if the concentrations are 

below the MDL the Permittee reports ND for non-detectable. For average monthly limits, all 

values above the MDL are used as reported and all values below the MDL are calculated as zero. 

Fact Sheet Page 54 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
LAB ACCREDITATION 

With the exception of certain parameters the permit requires all monitoring data to be prepared 

by a laboratory registered or accredited under the provisions of Chapter 173-50 WAC, 

Accreditation of Environmental Laboratories. The Intalco laboratory is currently accredited for: 

Chloride SM4500-Cl E 

Chlorine Residual, Total SM4500-Cl G 

Cyanide, Total EPA335.3 

Cyanide, Weak Acid Dissociable SM4500-CN I 

Fluoride SM4500-F E 

Hexane Extractable Material EPA1664 

pH SM4500-H 

Solids, Total Suspended SM2540 D 

Specific Conductance EPA120.1 

Sulfate SM4500-SO4 F 

Aluminum EPA200.7, EPA6010 

Calcium EPA200.7, EPA6010 

Copper EPA200.7, EPA6010 

Potassium SM3500-K B 

Sodium EPA200.7, EPA6010 

OTHER PERMIT CONDITIONS 

OUTFALL 002 DIVERSION 

Permit Condition S1.D requires Intalco to construct a diversion structure so that nearly all 

stormwater would discharge through Outfall 001 (process water outfall) rather than Outfall 002 

(the existing stormwater outfall). Only stormwater flows in excess of the hydraulic capacity of 

Outfall 001 would be discharged through Outfall 002. It is predicted that a discharge of 

stormwater through Outfall 002 would occur very infrequently, approximately once every five 

years or less. This discharge would take place during a high volume short duration rain event, 

typically during winter or spring months. 

Fact Sheet Page 55 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
As discussed elsewhere in the fact sheet, Intalco has a history of toxicity problems in the 

discharge from Outfall 002. The sources of many of these problems have been corrected and 

will continue to be addressed by implementing and following BMPs at the smelter. However, 

the location of the Outfall 002 structure is an ongoing concern; it currently discharges to fairly 

shallow water and is not equipped with a diffuser. Stormwater discharged through Outfall 002 

has the potential to cause toxicity and temperature impacts in the receiving water despite 

Intalco’s ability to comply with permit limits and water quality standards at the edge of the 

mixing zone. 

Receiving water temperature and toxicity are of particular concern because of the presence of 

Cherry Point herring. Cherry Point herring have historically spawned in the vicinity of and at the 

depth of the discharge of Outfall 002. The Cherry Point herring’s rate of development is 

temperature dependent and there has been a demonstrated increase in receiving water 

temperature in their spawning areas. 

Cherry Point herring populations are currently rebounding after being severely depressed to near 

extinction. The receiving water environment needs to be properly managed so that the herring 

stock continue to increase their numbers and have every chance to rebuild. 

Ecology has determined that the best way to minimize potential toxicity and temperature impacts 

in the receiving water is to require Intalco to implement additional BMPs and to divert the 

Outfall 002 discharge through Outfall 001. Outfall 001 is in deeper water and discharges 

through a diffuser away from the herring spawning habitat. It has better dilution within the 

mixing zone so discharging stormwater from Outfall 002 to Outfall 001 will provide greater 

water quality protection. 

Following the diversion, monitoring will continue at the outlet of the stormwater pond to ensure 

the effectiveness of upstream treatment. The permit specifies action levels for the stormwater 

discharge at which Intalco will be required to investigate potential problems and take corrective 

action as necessary. The permit also requires monitoring for any discharges at Outfall 002 after 

the diversion. 

TEMPORARY CURTAILMENT 

A condition is included in the permit allowing the Permittee to petition for reduced monitoring 

and the suspension of studies and certain permit requirements during temporary curtailment of 

smelter operations. 

REPORTING AND RECORDKEEPING 

The conditions in S2. of the permit are based on the authority to specify any appropriate 

monitoring, reporting and recordkeeping requirements to prevent and control waste discharges 

(WAC 173-220-210). 

Fact Sheet Page 56 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
OPERATION AND MAINTENANCE MANUAL 

In accordance with state and federal regulations, the Permittee is required to take all reasonable 

steps to properly operate and maintain their wastewater treatment systems (40 CFR 122.41(e)) 

and WAC 173-220-150 (1)(g). An operation and maintenance (O & M) manual was submitted 

as required by state regulation for the construction of wastewater treatment facilities (WAC 173-

240-150). Intalco is required to update the O&M manual (per Condition S3 of the permit) to 

include changes made to the PWTS, the SWTS, and the anode cooling water treatment system as 

described in Condition S10 of the permit. It has been determined that the implementation of the 

procedures in the O & M manual and Treatment System Operating Plan is a reasonable measure 

to ensure compliance with the terms and limitations in the permit. 

SOLID WASTE PLAN 

Ecology has determined that the Permittee has a potential to cause pollution of the waters of the 

state from leachate of solid waste. 

This permit requires, under the authority of RCW 90.48.080, that the Permittee update the solid 

waste plan designed to prevent solid waste from causing pollution of the waters of the state. The 

plan must be submitted to the local permitting agency for approval, if necessary, and to Ecology. 

The Permittee shall not allow leachate from its solid waste material to enter state waters without 

providing all known, available, and reasonable methods of treatment, nor allow such leachate to 

cause violations of the State Surface Water Quality Standards, Chapter 173-201A WAC, or the 

State Ground Water Quality Standards, Chapter 173-200 WAC. The Permittee shall apply for a 

permit or permit modification as may be required for such discharges to state ground or surface 

waters. 

The Permittee shall manage the pile of furnace brick from the anode plant located adjacent to the 

solid waste landfill in accordance with the management plan required by the Whatcom County 

Health Department. The management plan shall emphasize recycling as much of the brick as 

possible and disposing of the remainder in the on-site landfill. 

NON-ROUTINE AND UNANTICIPATED DISCHARGES 

Occasionally, this facility may generate wastewater which is not characterized in their permit 

application because it is not a routine discharge and was not anticipated at the time of 

application. This wastewater is typically water used to pressure test storage tanks or fire water 

systems or leaks from drinking water systems. It is typically clean but may be contaminated 

with pollutants. The permit contains an authorization for non-routine and unanticipated 

discharges. The authorization requires prior characterization of these wastewaters for pollutants 

and examination of the opportunities for reuse. Depending on the nature and extent of pollutants 

in this wastewater and opportunities for reuse, Ecology may authorize a direct discharge via the 

process wastewater outfall or through a stormwater outfall for clean water, require the 

wastewater to be placed through the facilities wastewater treatment process, or require the water 

to be reused. 

Fact Sheet Page 57 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
SPILL PLAN 

Ecology has determined that the Permittee stores a quantity of chemicals that have the potential 

to cause water pollution if accidentally released. Ecology has the authority to require the 

Permittee to develop best management plans to prevent this accidental release under section 

402(a)(1) of the Federal Water Pollution Control Act (FWPCA) and RCW 90.48.080. 

The Permittee has developed a plan for preventing the accidental release of pollutants to state 

waters and for minimizing damages if such a spill occurs. The permit requires the Permittee to 

update this plan and submit it to Ecology. 

TREATMENT EFFICIENCY STUDIES 

PRIMARY WASTEWATER TREATMENT SYSTEM (PWTS) AND SECONDARY WASTEWATER 

TREATMENT SYSTEM (SWTS) 

Intalco is required to operate process wastewater treatment systems according to procedures and 

criteria described in an operating plan. The previous permit required Intalco to update and 

maintain operational plans onsite for the process wastewater treatment systems. Intalco’s PWTS 

is a clarifier that is used to treat the wastewater from the wet air pollution control system (wet 

scrubbers). The Secondary Wastewater Treatment System (SWTS) is comprised of several 

treatment tanks and a clarifier. The wastewater from the PWTS and landfill leachate is treated 

through chemical precipitation and sedimentation in the SWTS. 

Condition S10.A. of the permit requires Intalco to update their O&M Plan to include their 

operational plan for the PWTS. Condition S10.B. requires Intalco to conduct a treatment 

efficiency study on the SWTS to determine if it meeting the design criteria and to propose and 

implement any changes needed to upgrade the system. 

 

ANODE COOLING WATER

Anode contact water is generated during the anode production process. This wastewater is 

filtered through a screen before it is commingled with other treated wastewaters and discharged 

through Outfall 001. 

Ecology is requiring Intalco (Condition S10.C of the permit) to complete a study of the anode 

contact cooling water filtration system to determine if it meets AKART standards. If the system 

does not meet AKART, Intalco will be required to upgrade the system to AKART standards. 

OUTFALL EVALUATION 

In accordance with Condition S.6 of the previous permit, Intalco conducted an underwater 

inspection of Outfalls 001 and 002 in June 1999. Overall, both outfalls were in good condition. 

No significant damage or deterioration to the pipes was found. At Outfall 001, the clamp bolts 

located at Bent 64 were loose and the vertical support rod on Bent 65 was malfunctioning due to 

a failed weld at the pipe clamp connection. Intalco replaced the bolts on the pipe clamp at Bent 

Fact Sheet Page 58 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
64 and the support rod at Bent 65 and removed marine organisms fouling the diffuser openings 

during the scheduled pier maintenance program in 2000. 

Condition S12. in the permit requires the Permittee to conduct an outfall inspection once per 

permit cycle and submit a report detailing the findings of that inspection. The purpose of the 

inspection is to determine the condition of the discharge pipe and diffusers and to evaluate the 

extent of sediment accumulations in the vicinity of the outfall. 

BEST MANAGEMENT PRACTICES AND STORMWATER POLLUTION PREVENTION 

PLAN 

Condition S14.A. of the permit lists BMPs that will help to further reduce or eliminate pollutants 

in the process and stormwater that is discharged to Outfalls 001 and 002, respectively. 

Permit Condition S14.B., requires Intalco to demonstrate compliance with these BMPs or submit 

a compliance schedule to implement these BMPs in the Stormwater Pollution Prevention Plan. 

Intalco identified the listed BMPs in their Stormwater Pollution Prevention Plan and in their 

Stormwater Runoff Study Final Report (in the sections titled “As-Built Pond Engineering 

Report”, “Site Hydrologic Characterization”, Rainfall Characterization”, “Stormwater Model”, 

and “Stormwater Pond Characterization”) submitted in compliance with Conditions S.9 and S.11 

of the previous permit. 

The stormwater BMPs required in the permit generally fall into two categories, non-capital and 

capital improvements. Non-capital improvements are BMPs that eliminate or minimize exposure 

of stormwater runoff to pollutants. These BMPs include good housekeeping, preventive 

maintenance, inspections, sediment/erosion control, employee training, spill prevention and 

cleanup measures. Capital improvements are BMPs which prevent runoff from contacting storm 

water or which contain/divert/treat contaminated stormwater discharges so that they do not 

impact surface waters. These BMPs require capital expenditures and include detention/retention 

ponds, berms, treatment systems, covering systems, and stormwater diversions. 

GENERAL CONDITIONS 

General Conditions are based directly on state and federal law and regulations and have been 

standardized for all individual industrial NPDES permits issued by Ecology. 

PERMIT ISSUANCE PROCEDURES 

PERMIT MODIFICATIONS 

Ecology may modify this permit to impose numerical limitations, if necessary to meet Water 

Quality Standards for Surface Waters, Sediment Quality Standards, or Water Quality Standards 

for Ground Waters, based on new information obtained from sources such as inspections, 

effluent monitoring, outfall studies, and effluent mixing studies. 

Ecology may also modify this permit as a result of new or amended state or federal regulations. 

Fact Sheet Page 59 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
RECOMMENDATION FOR PERMIT ISSUANCE 

This permit meets all statutory requirements for authorizing a wastewater discharge, including 

those limitations and conditions believed necessary to control toxics, protect human health, 

aquatic life, and the beneficial uses of waters of the State of Washington. Ecology is 

recommending that this permit be issued for (5) years. 

Fact Sheet Page 60 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
REFERENCES FOR TEXT AND APPENDICES 

Cosmopolitan Engineering Group. 2006. Intalco Aluminum Corporation - Outfalls 001 and 002 

Dilution Ratio Study, revised November 2006. 

Crecelius, E. 2000. Concentration of Metals in Marine Water and Effluent of the Alcoa Intalco 

Works. Battelle Marine Sciences Laboratory, April 2000. 

Environmental Protection Agency (EPA) 

1992. National Toxics Rule. Federal Register, V. 57, No. 246, Tuesday, December 22, 1992. 

1991. Technical Support Document for Water Quality-based Toxics Control. EPA/505/2-

90-001. 

1985. Water Quality Assessment: A Screening Procedure for Toxic and Conventional 

Pollutants in Surface and Ground Water. EPA/600/6-85/002a. 

1983. Water Quality Standards Handbook. USEPA Office of Water, Washington, D.C. 

Tsivoglou, E.C., and J.R. Wallace. 

Washington State Department of Ecology. 

 1994. Permit Writer’s Manual. Publication Number 92-109 

Washington State Department of Ecology. 

 Laws and Regulations( http://www.ecy.wa.gov/laws-rules/index.html ) 

 Permit and Wastewater Related Information 

(http://www.ecy.wa.gov/programs/wq/wastewater/index.html 

Wright, R.M., and A.J. McDonnell. 

Fishcher, H.B., E.F. List, R.C.Y. Koh, J. Imberger, and N.H. Brooks, 1979. Mixing in Inland 

and Coastal Waters, Academic Press, Inc., Harcourt Brace Jovanovich Publishers, New York 

NW, pp. 126-127. 

Fact Sheet Page 61 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX A--PUBLIC INVOLVEMENT INFORMATION 

The Department has tentatively determined to reissue a permit to the Intalco Aluminum 

Corporation. The permit contains conditions and effluent limitations that are described in this 

fact sheet. 

The Department will publish a Public Notice of Draft (PNOD) on May 11, 2005 in the 

Bellingham Herald and the Ferndale Westside Record Journal to inform the public that a draft 

permit and fact sheet are available for review. Interested persons are invited to submit written 

comments regarding the draft permit. The draft permit, fact sheet, and related documents are 

available for inspection and copying between the hours of 8:00 a.m. and 5:00 p.m. weekdays, by 

appointment, at the Ecology office listed below. Written comments should be mailed to: 

 Judy Schwieters 

 Department of Ecology 

 Industrial Section 

 P.O. Box 47706 

Olympia, WA 98504-7706 

Any interested party may comment on the draft permit or request a public hearing on this draft 

permit within the sixty (60) day comment period. All comments and requests for a hearing must 

be submitted in writing to the address above by the 5:00 p.m.on Monday July 11, 2005. The 

request for a hearing shall indicate the interest of the party and reasons why the hearing is 

warranted. The Department will hold a hearing if it determines there is a significant public 

interest in the draft permit (WAC 173-220-090). Public notice regarding any hearing will be 

circulated at least thirty (30) days in advance of the hearing. People expressing an interest in this 

permit will be mailed an individual notice of hearing (WAC 173-220-100). 

Comments should reference specific text followed by proposed modification or concern when 

possible. Comments may address technical issues, accuracy and completeness of information, 

the scope of the facility’s proposed coverage, adequacy of environmental protection, permit 

conditions, or any other concern that would result from issuance of this permit. 

The Department will consider all comments received within thirty (30) days from the date of 

public notice of draft indicated above, in formulating a final determination to issue, revise, or 

deny the permit. The Department's response to all significant comments is available upon 

request and will be mailed directly to people expressing an interest in this permit. 

Further information may be obtained from the Department by telephone, (360) 407-6955, or by 

writing to the address listed above. 

This permit and fact sheet were written by Liem Nguyen and Judy Schwieters. 

Update: 

Public Notice Published: May 11, 2005 

Public Comment Period: May11, 2005 through July22, 2005 

Fact Sheet Page 62 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX B--GLOSSARY 

Acute Toxicity--The lethal effect of a compound on an organism that occurs in a short period of 

time, usually 48 to 96 hours. 

AKART-- An acronym for “all known, available, and reasonable methods of treatment”. 

Ambient Water Quality--The existing environmental condition of the water in a receiving 

water body. 

Ammonia--Ammonia is produced by the breakdown of nitrogenous materials in wastewater. 

Ammonia is toxic to aquatic organisms, exerts an oxygen demand, and contributes to 

eutrophication. It also increases the amount of chlorine needed to disinfect wastewater. 

Average Monthly Discharge Limitation --The average of the measured values obtained over a 

calendar month's time.

Best Management Practices (BMPs)--Schedules of activities, prohibitions of practices, 

maintenance procedures, and other physical, structural and/or managerial practices to prevent 

or reduce the pollution of waters of the State. BMPs include treatment systems, operating 

procedures, and practices to control: plant site runoff, spillage or leaks, sludge or waste 

disposal, or drainage from raw material storage. BMPs may be further categorized as 

operational, source control, erosion and sediment control, and treatment BMPs. 

BOD5--Determining the Biochemical Oxygen Demand of an effluent is an indirect way of 

measuring the quantity of organic material present in an effluent that is utilized by bacteria. 

The BOD5 is used in modeling to measure the reduction of dissolved oxygen in a receiving 

water after effluent is discharged. Stress caused by reduced dissolved oxygen levels makes 

organisms less competitive and less able to sustain their species in the aquatic environment. 

Although BOD is not a specific compound, it is defined as a conventional pollutant under the 

federal Clean Water Act. 

Bypass--The intentional diversion of waste streams from any portion of a treatment facility. 

Chlorine--Chlorine is used to disinfect wastewaters of pathogens harmful to human health. It is 

also extremely toxic to aquatic life. 

Chronic Toxicity--The effect of a compound on an organism over a relatively long time, often 

1/10 of an organism's lifespan or more. Chronic toxicity can measure survival, reproduction 

or growth rates, or other parameters to measure the toxic effects of a compound or 

combination of compounds. 

Clean Water Act (CWA)--The Federal Water Pollution Control Act enacted by Public Law 92-

500, as amended by Public Laws 95-217, 95-576, 96-483, 97-117; USC 1251 et seq. 

Compliance Inspection - Without Sampling--A site visit for the purpose of determining the 

compliance of a facility with the terms and conditions of its permit or with applicable statutes 

and regulations. 

Fact Sheet Page 63 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX B—GLOSSARY (CONTINUED) 

Compliance Inspection - With Sampling--A site visit to accomplish the purpose of a 

Compliance Inspection - Without Sampling and as a minimum, sampling and analysis for all 

parameters with limits in the permit to ascertain compliance with those limits; and, for 

municipal facilities, sampling of influent to ascertain compliance with the 85 percent removal 

requirement. Additional sampling may be conducted. 

Composite Sample--A mixture of grab samples collected at the same sampling point at different 

times, formed either by continuous sampling or by mixing discrete samples. May be "timecomposite"(collected at constant time intervals) or "flow-proportional" (collected either as a 

constant sample volume at time intervals proportional to stream flow, or collected by 

increasing the volume of each aliquot as the flow increased while maintaining a constant time 

interval between the aliquots. 

Construction Activity--Clearing, grading, excavation and any other activity which disturbs the 

surface of the land. Such activities may include road building, construction of residential 

houses, office buildings, or industrial buildings, and demolition activity. 

Continuous Monitoring –Uninterrupted, unless otherwise noted in the permit. 

Critical Condition--The time during which the combination of receiving water and waste 

discharge conditions have the highest potential for causing toxicity in the receiving water 

environment. This situation usually occurs when the flow within a water body is low, thus, 

its ability to dilute effluent is reduced. 

Dilution Factor--A measure of the amount of mixing of effluent and receiving water that occurs 

at the boundary of the mixing zone. Expressed as the inverse of the percent effluent fraction 

e.g., a dilution factor of 10 means the effluent comprises 10% by volume and the receiving 

water 90%. 

Engineering Report--A document which thoroughly examines the engineering and 

administrative aspects of a particular domestic or industrial wastewater facility. The report 

shall contain the appropriate information required in WAC 173-240-060 or 173-240-130. 

Fecal Coliform Bacteria--Fecal coliform bacteria are used as indicators of pathogenic bacteria 

in the effluent that are harmful to humans. Pathogenic bacteria in wastewater discharges are 

controlled by disinfecting the wastewater. The presence of high numbers of fecal coliform 

bacteria in a water body can indicate the recent release of untreated wastewater and/or the 

presence of animal feces. 

Grab Sample--A single sample or measurement taken at a specific time or over as short period 

of time as is feasible. 

Fact Sheet Page 64 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX B—GLOSSARY (CONTINUED) 

Industrial Wastewater--Water or liquid-carried waste from industrial or commercial processes, 

as distinct from domestic wastewater. These wastes may result from any process or activity 

of industry, manufacture, trade or business, from the development of any natural resource, or 

from animal operations such as feed lots, poultry houses, or dairies. The term includes 

contaminated storm water and, also, leachate from solid waste facilities. 

Major Facility--A facility discharging to surface water with an EPA rating score of > 80 points 

based on such factors as flow volume, toxic pollutant potential, and public health impact. 

Maximum Daily Discharge Limitation--The highest allowable daily discharge of a pollutant 

measured during a calendar day or any 24-hour period that reasonably represents the calendar 

day for purposes of sampling. The daily discharge is calculated as the average measurement 

of the pollutant over the day. 

Method Detection Level (MDL)--The minimum concentration of a substance that can be 

measured and reported with 99% confidence that the analyte concentration is above zero and 

is determined from analysis of a sample in a given matrix containing the analyte. 

Minor Facility--A facility discharging to surface water with an EPA rating score of < 80 points 

based on such factors as flow volume, toxic pollutant potential, and public health impact. 

Mixing Zone--An area that surrounds an effluent discharge within which water quality criteria 

may be exceeded. The area of the authorized mixing zone is specified in a facility's permit 

and follows procedures outlined in state regulations (Chapter 173-201A WAC). 

National Pollutant Discharge Elimination System (NPDES)--The NPDES (Section 402 of the 

Clean Water Act) is the Federal wastewater permitting system for discharges to navigable 

waters of the United States. Many states, including the State of Washington, have been 

delegated the authority to issue these permits. NPDES permits issued by Washington State 

permit writers are joint NPDES/State permits issued under both State and Federal laws. 

pH--The pH of a liquid measures its acidity or alkalinity. A pH of 7 is defined as neutral, and 

large variations above or below this value are considered harmful to most aquatic life. 

Quantitation Level (QL)-- A calculated value five times the MDL (method detection level). 

Practical Quantitation Limit (PQL) -- is the lowest level that can be 

reliably achieved within specified limits of precision and accuracy during routine 

laboratory operating conditions. The PDL is a calculated value that is five times the MDL 

(method detection level). 

Responsible Corporate Officer-- A president, secretary, treasurer, or vice-president of the 

corporation in charge of a principal business function, or any other person who performs 

similar policy- or decision-making functions for the corporation, or the manager of one or 

more manufacturing, production, or operating facilities employing more than 250 persons or 

have gross annual sales or expenditures exceeding $25 million (in second quarter 1980 

dollars), if authority to sign documents has been assigned or delegated to the manager in 

accordance with corporate procedures (40 CFR 122.22). 

Fact Sheet Page 65 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX B—GLOSSARY (CONTINUED) 

Technology-based Effluent Limit--A permit limit that is based on the ability of a treatment 

method to reduce the pollutant. 

Total Suspended Solids (TSS)--Total suspended solids is the particulate material in an effluent. 

Large quantities of TSS discharged to a receiving water may result in solids accumulation. 

Apart from any toxic effects attributable to substances leached out by water, suspended solids 

may kill fish, shellfish, and other aquatic organisms by causing abrasive injuries and by 

clogging the gills and respiratory passages of various aquatic fauna. Indirectly, suspended 

solids can screen out light and can promote and maintain the development of noxious 

conditions through oxygen depletion. 

State Waters--Lakes, rivers, ponds, streams, inland waters, underground waters, salt waters, and 

all other surface waters and watercourses within the jurisdiction of the state of Washington. 

Stormwater--That portion of precipitation that does not naturally percolate into the ground or 

evaporate, but flows via overland flow, interflow, pipes, and other features of a storm water 

drainage system into a defined surface water body, or a constructed infiltration facility. 

Upset--An exceptional incident in which there is unintentional and temporary noncompliance 

with technology-based permit effluent limitations because of factors beyond the reasonable 

control of the Permittee. An upset does not include noncompliance to the extent caused by 

operational error, improperly designed treatment facilities, lack of preventative maintenance, 

or careless or improper operation. 

Water Quality-based Effluent Limit--A limit on the concentration of an effluent parameter that 

is intended to prevent the concentration of that parameter from exceeding its water quality 

criterion after it is discharged into a receiving water. 

Fact Sheet Page 66 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX C--TECHNICAL CALCULATIONS 

Several of the Excel® spreadsheet tools used to evaluate a discharger’s ability to meet 

Washington State water quality standards can be found on the Department’s homepage at 

http://www.ecy.wa.gov/programs/wq/wastewater/index.html. 

Fact Sheet Page 67 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
APPENDIX D—RESPONSE TO COMMENTS 

APPENDIX E—MAP OF DISCHARGE LOCATIONS 

APPENDIX F—SUMMARY OF NONCOMPLIANCE 

APPENDIX G—DISCHARGE MONITORING SUMMARY 

APPENDIX H—WASTEWATER CHARACTERIZATION 

APPENDIX I—COPPER MONITORING RESULTS 

APPENDIX J—MIXING ZONE ANALYSES 

APPENDIX K—TEMPERATURE ANALYSIS 

APPENDIX L—REASONABLE POTENTIAL TO EXCEED (AQUATIC LIFE 

CRITERIA AND HUMAN HEALTH) ANALYSES FOR OUTFALL 001 

APPENDIX L—REASONABLE POTENTIAL TO EXCEED (AQUATIC LIFE 

CRITERIA AND HUMAN HEALTH) ANALYSES FOR OUTFALL 002 

APPENDIX M—ACUTE AND CHRONIC WET TEST RESULTS FOR OUTFALLS 001 

&002 

APPENDIX N—LANDFILL MONITORING RESULTS 

APPENDIX O—PERFORMANCE BASED REDUCTION OF MONITORING 

FREQUENCIES 

Fact Sheet Page 68 of 68 Revised at Permit Issuance 03/15/07 

Intalco NPDES Permit (WA-000295-0) 
% multiplier Cost Note

Capital Costs

Purchased Equipment Costs

capital costs $ 51,187,853

CEMS $ 40,000 one SO2 CEM system

instrumentation 5% $ 2,561,393 scaled back from 10% CC Manual since basic inst is included in proposal

sales tax 8.20% $ 4,200,684 State 6.5% plus local 1.7%

freight 5% $ 2,561,393 CC Manual

PEC $ 60,551,322

Installation Costs

foundations 12% $ 7,266,159

erection 80% $ 48,441,058 Cost manual default is 40%.

electical 1% $ 605,513

piping 30% $ 18,165,397

inslulation 1% $ 605,513

field painting 1% $ 605,513

TIC $ 75,689,153

Indirect Costs

engineering 5% $ 3,027,566 Cost manual 10%, but bid includes some engineering expenses

construction 10% $ 6,055,132

EPA Region 10 - High

Vendor #1 dual-absorber capital cost, scaled to single absorber cost based on 

Vendor #2

construction 10% $ 6,055,132

contractor fees 5% $ 3,027,566

start-up 1% $ 605,513

performance test 1% $ 605,513

contingencies 3% $ 1,816,540

aquatic studies $ 235,000 Nov 16, 18, and 22 conversations with Kyle Murphy, WA DNR

PUD water connection fee $ 300,000 12/8/11 conversation with Stephan Jilk, Whatcom PUD

Total Indirect Cost $ 15,672,831

Total Capital Investment Cost (TCIC) $ 151,913,306

Capital Recovery

Interest rate 7%

Equipment lifetime 30

Capital cost recovery factor 0.0806 Calculated via Equation 1.34 in the EPA CC Manual

Annual Capital cost $ 12,242,147

Annual Costs

Direct Annual Costs

Operating labor

Operator $ 37.00 $ 324,120

Supervisor 15% $ 48,618

one full time operator, 3 shifts/day

Cost manual 10%, but assumes scrubber vendor will oversee scrubber 

installation and include in capital of equipment

Supervisor 15% $ 48,618

Water

Cost $ 0.00070 $/gal 12/8/11 conversation with Stephan Jilk, Whatcom PUD

Quantity 500,000 Gal/day Pre Feasibility

Annual cost $ 127,750

Limestone usage, tons/yr 14,244.00

Limestone cost/ton $ 33.00

Annual Limestone cost $ 470,052

Compressed air

Plant cost $ 0.24 $/1000 scfm

Quantity 150.00 scfm

Annual cost $ 18,922

Gypsum disposal

Generation rate 6,194.00 lb/hr

 27,130 ton/yr

Cost disposal $/ton nonhazardous solid waste, including transportation

Annual cost $ -

Maintenance Labor $ 45.00 $ 673,920

Materials $ 1,303,000

Elctricity

4 full time maintenance personnel, one shift/day, 5 days/week and 1 

maintenance personnel for all other shifts

Required 7,400.00 KWh/hr Pre Feasibility report

Cost $ 0.05 $/kWh 2007 cost per Intalco

Total Cost $ 3,409,742

Total Direct Annual costs $ 6,376,124

Indirect Annual Costs

Overhead 60% $ 1,409,795 CC Manual, section 2.5.5.7

General and Administrative 2% $ 3,038,266 CC Manual, section 2.5.5.7

Property Tax 1% $ 1,519,133 CC Manual, section 2.5.5.7

Insurance 1% $ 1,519,133 CC Manual, section 2.5.5.7

Total Indirect Annual Costs $ 7,486,327

Total Annual O&M Costs $ 13,862,451

Total Annual Costs $ 26,104,598

SOX Reduction 5983 Assuming 2 week annual shutdown and bypass emissions

$/ton of SOX $ 4,363
% multiplier Cost Note

Capital CostsPurchased Equipment Costscapital costs $ 51,187,853CEMS $ 40,000 one SO2 CEM systeminstrumentation 5% $ 2,561,393 scaled back from 10% CC Manual since basic inst is included in proposalsales tax 8.20% $ 4,200,684 State 6.5% plus local 1.7%freight 5% $ 2,561,393 CC ManualPEC $ 60,551,322Installation Costsfoundations 12% $ 7,266,159erection 40% $ 24,220,529 Cost manual default is 40%.electical 1% $ 605,513piping 30% $ 18,165,397inslulation 1% $ 605,513field painting 1% $ 605,513TIC $ 51,468,624Indirect Costsengineering 5% $ 3,027,566 Cost manual 10%, but bid includes some engineering expensesconstruction 10% $ 6,055,132

EPA Region 10 - Low

Vendor #1 dual-absorber capital cost, scaled to single absorber cost based on Vendor #2

construction 10% $ 6,055,132contractor fees 5% $ 3,027,566start-up 1% $ 605,513performance test 1% $ 605,513contingencies 3% $ 1,816,540aquatic studies $ 235,000 Nov 16, 18, and 22 conversations with Kyle Murphy, WA DNRPUD water connection fee $ 300,000 12/8/11 conversation with Stephan Jilk, Whatcom PUDTotal Indirect Cost $ 15,672,831Total Capital Investment Cost (TCIC) $ 127,692,777Capital RecoveryInterest rate 7%Equipment lifetime 30Capital cost recovery factor 0.0806 Calculated via Equation 1.34 in the EPA CC ManualAnnual Capital cost $ 10,290,302Annual CostsDirect Annual CostsOperating labor

Operator $ 37.00 $ 324,120Supervisor 15% $ 48,618

Cost manual 10%, but assumes scrubber vendor will oversee scrubber installation and include in capital of equipmentone full time operator, 3 shifts/day

Supervisor 15% $ 48,618

Water

Cost $ 0.00070 $/gal 12/8/11 conversation with Stephan Jilk, Whatcom PUDQuantity 500,000 Gal/day Pre FeasibilityAnnual cost $ 127,750

Limestone usage, tons/yr 14,244.00Limestone cost/ton $ 33.00

Annual Limestone cost $ 470,052

Compressed air

Plant cost $ 0.24 $/1000 scfmQuantity 150.00 scfmAnnual cost $ 18,922
Attachment 12 - EPA Region 10 LSFO Capital Cost Scaling Summary Table

Reagent Feed System 10% 0.33 $6,500,000 $8,200,000 $7,350,000 $7,8SO2 Removal System 35% 0.5 $22,750,000 $28,700,000 $25,725,000 $28,5Flue Gas System 30% 0.5 $19,500,000 $24,600,000 $22,050,000 $24,4By-product Handling System 10% 0.4 $6,500,000 $8,200,000 $7,350,000 $8,1General Support Equipment 15% 0.15 $9,750,000 $12,300,000 $11,025,000 $11,4

$65,000,000 $82,000,000 $73,500,000 $80,4

Clean flue gas flow (acfm)Gypsum production (tpa)Gypsum production (tpa)

Scrubber 

Component

Fraction of 

Total 

Equipment 

Cost

Scaling 

Equation 

Exponent

Limestone consumption (tpa)Clean flue gas flow (acfm)

Scaling Parameter

Scaled Aver

Vendor #1 

Vendor #2 Q

(Enviro

Tennessee Potline Scrubber Equipment Costs

Vendor #1 

Quote

Vendor #2 

Quote Average
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

1

MARKET REVIEW 

FOR 

INTALCO PRODUCED FGD GYPSUM 

 

 

 

 

 

 Elliot Rosenberg, Senior Economist 

 March 23, 2012 

 
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

2

 

 Premise: Starting about 2017 the proposed installation of scrubbers at Alcoa’s 

 Intalco aluminum smelting facility at Ferndale Washington would 

 become operational. A by-product of the scrubbers’ operation at full 

 capacity would be an estimated 27,000 tons of FGD gypsum annually. 

 The estimated cost for the disposal of this FGD gypsum at a permitted 

 landfill is estimated to be $145 per ton (equal to $3.915 million 

 annually). 

 

 Task: As a possible lower cost alternative to landfill disposal - 

 A. Determine if there would be a market for Intalco’s FGD 

 gypsum. 

 If there is a market - 

 B. Can this FGD gypsum be sold at a lower cost than would be 

 incurred for landfill disposal? 

SUMMARY

As a result of continuing discussions with EPA Region 10 concerning the treatment of sulfur 

dioxide (SO2) being emitted from Intalco’s Ferndale Washington aluminum smelting facility 

(“Intalco”, “the Ferndale facility”) through the installation of scrubbers, gypsum would be 

produced as a by-product through a process known as Flu Gas Desulfurization (FGD). Gypsum 

produced through this process is referred to as FGD gypsum, synthetic gypsum, or syn-gyp. FGD 

gypsum is one of two primary sources of gypsum; the other gypsum source is from mining and is 

referred to as mined gypsum, crude gypsum or raw gypsum. Intalco’s consultant estimates that 

when the Ferndale facility is operating at full capacity approximately 27,000 tons of FGD 

gypsum would be produced annually, starting about 2017. 

Since disposal of this Intalco’s FGD gypsum at a permitted landfill is relatively costly, and these 

landfill disposal costs significantly impact the standard air quality cost effectiveness for the 

proposed scrubbers1

, the issue for this review was to determine if a market could potentially exist 

for this FGD gypsum. In their cost effectiveness analysis for the proposed scrubber Intalco’s 

consultant assumed disposal costs of $145 per ton including transportation (Environ 2007), equal 

to more than $3.9 million annually operating at full capacity. For this review from a cost 

effectiveness perspective a viable market alternative to landfill disposal means Intalco’s 

alternative ‘disposal’ cost should be less than $145 per ton, i.e., less than the disposal cost at a 

landfill. Ideally this means Intalco would be able to sell its FGD gypsum for a net profit or at 

least break-even. The price Intalco offers for its FGD gypsum, i.e., the company’s sale price, 

                                                           

1 In determining the cost effectiveness of this project proposal, the analysis uses annualized capital costs, and the

project’s annual O&M (operating and maintenance) costs.   
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

3

would be FOB the Ferndale facility2. The final price would be negotiated between Intalco and 

the buyer. 

Indentifying a prospective market (or markets) for Intalco’s FGD gypsum starting about 2017 

infers several conditions, e.g., 

 - there would exist one or more commercial applications for FGD gypsum 

 - the end-user for this FGD gypsum would likely exist within a reasonable distance of the 

 Ferndale facility, implying transportation costs could be an important consideration for 

 the sale of Intalco’s FGD gypsum 

 - Intalco is able to attract a buyer (or buyers) at its FOB price, and 

 - Intalco would be able to secure a long-term contract (e.g., 10 years or more duration) 

Within the confines of this review a prospective market for Intalco’s FGD gypsum was 

determined by identifying current uses for FGD gypsum, relevant supply and demand issues, 

relevant prices, and some market trends. While there are numerous commercial uses for FGD 

gypsum, a large percentage of current FGD gypsum is used in the production of wallboard, and 

the next largest use though a distant second is in the production of cement. 

One fundamental issue is whether Intalco can sell into the FGD gypsum market. This means 

identifying supply side issues that can impact a buyer’s decision to purchase Intalco’s FGD 

gypsum. Assuming that all FGD gypsum is of equal or very similar quality, and prospective 

buyers are free to purchase FGD gypsum without any constraints3, it is necessary to determine 

the size of the FGD gypsum market (production and use), preferably a geographically relevant 

market, and understanding Intalco’s annual production of FGD gypsum as a percentage of total 

FGD gypsum production and use, again preferably within our geographic region. One problem is 

that relevant geographic data can be difficult or impossible to obtain. This means that a 

geographically broader perspective would be the only option available, 4 but the resulting data 

could be less relevant for identifying the prospective market for Intalco’s FGD gypsum. Based 

on broader geographic data, the most current data (for 2011) indicates that Intalco’s annual 

estimated annual production of 27,000 tons of FGD gypsum would equal about 0.000084% of 

total annual U.S. production (other things held constant). 

Using the available though limited information, and in consideration of: the current overall U.S. 

gypsum market; the potentially increasing demand for FGD gypsum for wallboard production, 

cement and agricultural markets; the potential for Intalco’s FGD gypsum to be sold as either as a 

non-calcined or calcined product – where the latter product sells at a significantly higher price 

                                                           

2 FOB = Free on Board. Defined here where the buyer pays for the FGD gypsum and loading at the Ferndale facility.

The buyer is then responsible for transportation to the buyer’s site, and unloading costs. If Intalco pays the loading

cost, then this cost could be reflected in Intalco’s FOB price.    3 That is, buyers are not locked into long‐term agreements, or there is excess demand amongst buyers who are

already locked into contracts for the supply of FGD gypsum.   4 For government reported statistics, where only one or several entities exist and could therefore be easily

identified with the disclosure of their respective data, then by necessity that data then has to be aggregated to a

larger geographic region (i.e., the inclusion of additional data), thereby obviating the possibility of identification of

the source or sources  of this data.   
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

4

compared to the former; the considerable price differential between crude gypsum and FGD 

gypsum, the latter selling at a significant discount to crude gypsum; and the relatively small 

though consistent (prospective) supply of Intalco FGD gypsum as a share of the total market - 

leads me to conclude there could be a prospective market or markets for Intalco’s FGD gypsum. 

Even at an FOB price of $0.00 – in effect the FGD gypsum was free and the buyer only paid for 

loading5

 (and transportation) - Intalco would still realize considerable savings compared to 

incurring the landfill disposal related costs. 

MARKET REVIEW

This review relied on readily available information from several sources in order to determine if 

there is a prospective market for Intalco’s FGD gypsum, starting about 2017. An important 

consideration to keep in mind is that this market determination is forecasted for a period starting 

about five years out and carries with it typical caveats, primarily the issue of forecast reliability. 

Any forecast at this time is based on best professional judgment. 

Primary Reliance on Two Analytical Approaches

The review primarily relied on two approaches: 

 - fundamental analysis: defined here as the study of basic, underlying factors that will 

 affect the supply and demand of the commodity (CFTC 2011) 

 - trend analysis: the study of the general direction of commodity prices, quantities, and 

 other relevant commodity and market statistics over time – used as a method for 

 generally forecasting those relevant elements 

Fundamental Analysis of the FGD Synthetic Gypsum Market 

 The Market

 The FGD Gypsum Market by Use

 FGD gypsum has many diverse applications in the U.S. market 

 (FGDProducts.org), for example in: 

 Wallboard 

o Regular 

o Sheathing 

o Soffit board 

 Water resistant gypsum 

 Cement 

 Lath 

 Wood chip boards 

 Structural Fill 

 Mining Applications 

                                                           

5 Or if Intalco paid for loading, then the FOB price would be: FOB = loading cost per ton  
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

5

o Neutralization or encapsulation of acid-producing 

materials 

o Barrier to acid mine drainage formation 

o Alkaline amendment to neutralize acid-producing rock 

o Subsidence control in underground mines 

 Soil amendment 

 Synthetic soil component 

 Set retarder in portland cement 

 Plaster 

 Agriculture 

o Acid soil amelioration 

o Sodic soil reclamation 

o Surface crust reduction 

o Runoff and erosion reduction 

o Feedlot surface stabilization 

o Fertilizer 

 Glass Making 

 Pigments and/or Fillers 

 Examples of more esoteric applications for gypsum include its use in: 

 Tofu 

 Home brew 

 Foot creams, shampoos, and other hair products 

 Shi Gao6

 Identifying Realistic Markets for Intalco’s FGD Gypsum

 One consideration in determining a realistic market for Intalco’s FGD gypsum is the ability 

 of that market to absorb Intalco’s entire annual production of FGD gypsum on an ongoing

 and consistent periodic basis. Maximum annual FGD gypsum production was estimated by 

 Intalco’s consultant at 27,000 tons per year (EPA 2012), or 2,250 tons per month. This 

 annual production estimate is based on all three potlines at the Ferndale facility being in 

 operation, starting about 2017.7 Other assumptions include: 

 - electric power costs remain relatively constant8

 - there will be limited (though unknown at this time) storage capacity at the Ferndale 

 facility for the FGD gypsum produced. This will determine the minimum frequency for 

 shipping out the FGD gypsum, and 

 - FGD gypsum will be produced by the Ferndale facility at a uniform rate throughout the 

 year. 

                                                           

6 Certain gypsum used as a component in traditional Chinese medicine. 7 Of course if operating at less than full capacity, then annual FGD gypsum would be less than the 27,000 tons per

year. This factor would have to be taken into consideration with any contractual obligation.   8 Electric power accounts for approximately 27% of Alcoa’s primary aluminum production costs, of which Alcoa

generates approximately 23% of the power used at its smelters worldwide.(Alcoa 2010, p.15) With respect to the

Intalco smelter, Alcoa and BPA signed a contract providing for the sale of power that ended May 26, 2011, with a

provision for a 5‐year extension if certain financial tests can be met. If this renewal was taken up then it provides

the Intelco facility with power price stability at least up to about the time syn‐gyp would start being

produced.(Alcoa 2010, p.16)   
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

6

 Therefore, under these assumptions the market must be able to absorb all of the Ferndale 

 facility’s FGD gypsum production. 

 So while FGD gypsum has many applications, it remains to identify a market or markets that 

 can (prospectively) readily absorb all of Intalco’s annual production of FGD gypsum. This 

 means understanding certain market conditions, e.g.: 

 - who are the ‘players’ in the FGD gypsum market, i.e., producers and buyers 

 - overall future FGD gypsum production vis-à-vis future demand 

 - Intalco’s annual FGD gypsum production vis-à-vis total national annual FGD gypsum 

 use 

 - at a minimum there is no substantive quality difference in FGD gypsum produced by 

 Intalco and other FGD gypsum producers, and perhaps Intalco’s FGD gypsum is of a 

 higher quality – and is that relevant 

 - to what extent, if any, does the market address any differences between FGD gypsum 

 (calcined and non-calcined) and crude gypsum – by price, by application? 

 - there should be no barriers to market entry for Intalco’s FGD gypsum 

 - recognizing the role transportation costs could play in determining the competitiveness of 

 Intalco produced FGD gypsum.9

 - to what extent can relevant market conditions be identified with respect to Intalco’s 

 geographic preferences 

 Gypsum Produced

 Production statistics developed by the U.S.G.S. do not actually reflect total U.S. 

 production, since the synthetic gypsum (i.e., FGD gypsum) statistic for production is defined 

 as ‘sold or used - not produced’. As shown in Table 1 estimated 2011 annual use of 

 synthetic gypsum (FGD gypsum) was 12,125,300 short tons.10. Assuming the same annual 

 use for 2017, Intalco’s annual production of 27,000 tons would equal 0.22% of estimated 

 total annual use of FGD gypsum in the U.S.! The American Coal Ash Association’s 

 (ACAA) conservative estimate for 2010 FGD gypsum production is 22,000,000 short tons 

 (ACAA 2010).11 Assuming this figure remains constant through 2017, Intalco’s annual 

 production would amount to no more than 0.12% of total annual U.S. production of 

 FGD gypsum! 

 Another factor to be considered is the location of gypsum production. As shown in the 

 U.S.G.S. section, while it appears no substantial amount of gypsum is produced in the greater 

 Pacific Northwest region (e.g. Washington, Idaho, and Oregon, Montana), FGD gypsum is 

 produced at the Trans Alta power generation plant in Centralia. The company’s website says 

 that it sold 89,100 metric tons of FGD gypsum in 2002 (Trans Alta 2012). Though the 

                                                           

9 One factor In Intalco’s favor is that one or more railroad sidings already exist at the Ferndale facility, thereby

facilitating facility access for railroad bulk carriers.   10 Converted from 11,000 metric tons as shown in Table 1.   11 The actual annual coal derived FGD gypsum production is actually much greater since ACAA indicates that its

survey data represent about 67% of the coal‐fueled electric generation as reported to the EIA (Energy Information

Agency).
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

7

 company will shut down one boiler by December 2020 and its second boiler by December 

 2025 (EPA 2012b), this factor would not appear to have any positive impact for Intalco’s 

 market entry around 2017, though it could possibly have a meaningful positive impact 

 subsequent to the boiler shutdowns.

 

 Price 

 Table 1 shows f.o.b. price estimates for gypsym. These price estimates indicate important 

 differentials between non-calcined crude, non-calcined synthetic, and calcined crude and 

 synthetic. Note there is a substantial price differential between non-calcined crude (i.e., 

 mined) and non-calcined synthetic, estimated to be between $3.63 to $5.44 per short ton.12

 (Table 1) The primary reason is in production costs between crude and FGD gypsum. The 

 former requires a considerable investment and ongoing expense for the specific purpose of 

 mining gypsum, while the latter is produced as a by-product from a process used to improve 

 air quality from certain sources. Hence, there is no direct cost incurred for the production of 

 FGD gypsum (other than storage and handling). If this spread between FGD gypsum and 

 crude gypsum prices remains about the same by 2017, this means that FGD gypsum, 

 including Intalco’s FGD gypsum, would have a real competitive advantage over crude 

 gypsum based on f.o.b. prices. Another significant cost for a buyer of gypsum f.o.b. the 

 gypsum producing facility is the shipping cost. So if a buyer of FGD gypsum can obtain its 

 gypsum from Ferndale as a source that is closer than any other FGD gypsum source, then the 

 prospective buyer would presumably pay less for transportation. Since Intalco would be 

 looking to move its FGD gypsum in the market place, it would be looking at minimizing its 

 FOB price in order to encourage a buyer to purchase its FGD gypsum, which concurrently 

 minimizes Intalco’s ‘disposal’ cost below $145 per ton. 

 

 Demand

 Also notice in Table 1 the price differential between non-calcined gypsum (synthetic and 

 crude), and calcined gypsum. The FOB13 plant price for calcined gypsum is estimated at 

 $27.22 per short ton in 2011, compared to an estimated FOB plant price for non-calcined of 

 $0.91 to $2.72 per short ton; a price differential of $24.50 to $26.31 per short ton. Because 

 calcined gypsum contains about one-quarter the moisture of non-calcined gypsum, shipping 

 costs are lower. Also, (certain) buyers may prefer calcined gypsum as a more usable product. 

 Calcined gypsum could be used directly as is, or water can always be added back in to meet 

 that user’s requirements. Should the proposed Intalco scrubber project proceed, whether 

 Intalco sells non-calcined or calcined FGD gypsum would depend on the buyer’s requirement 

 and whether producing calcined gypsum makes business sense. 

 

                                                           

12 It is my understanding (at this time) that there are no material differences between crude gypsum and syn‐gyp.   13 There are a number of ways to abbreviate Free on Board: FOB, F.O.B., f.o.b., etc. U.S.G.S. prefers f.o.b.
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

8

 Wallboard Market

 Based on the ACAA data, gypsum panel products (e.g., wallboard, etc.) consume about 72% 

 of (coal based) FGD gypsum; cement related uses about 11%; and agriculture about 4.5% 

 (ACAA 2010).14 These three markets are the focus of this review. 

 The U.S.G.S. expert indicated that though there was a decline in wallboard production 

 starting about 2008 (Table 1), subsequently there has been a somewhat slow increase in 

 wallboard production primarily tied to the housing market (ACAA 2010). At this time it is 

 not known if there are any wallboard producers in the greater Pacific Northwest region. If 

 there are, then their proximity to the Ferndale facility could indicate a prospective market for 

 Intalco’s FGD gypsum. 

 Local Cement Market

 With respect to prospective users of syn-gyp in the region, there are at least four and possibly 

 more cement kilns in the region (EPA, 2012): est. gypsum use* 

 Ash Grove Seattle, WA: 750,000 tons clinker per year 37,500 tons/yr 

 LaFarge Seattle, WA: 425,000 tons clinker per year 21,250 tons/yr 

 Ash Grove Durkee, OR: 940,000 tons clinker per year 47,000 tons/yr 

 Vancouver BC: there may be several cement kilns in the BC area 

 __________ 

 * For Portland cement production, the ratio is 95% clinker, 5% gypsum (EPA 2012; Taylor et al 2006). 

 

 Any of these cement kiln operators could be prospective sources for Intalco’s FGD 

 gypsum.15

 Agriculture Markets

 Gypsum is used as an agricultural amendment (Chen and Dick 2011). Gypsum application on 

 a variety of crops has demonstrated increased crop yield with no tillage when compared to 

 crops grown without gypsum using conventional tillage.(Chen and Dick 2011, p.24) 

 Increased crop yield where other farm costs remain constant or are reduced means increased 

 crop revenue, i.e., more income for the farmer. Chen and Dick indicate that “The costs 

 associated with using gypsum, including FGD gypsum, includes the costs of purchasing the 

 material, transporting it from the site of generation to the site of use, and spreading it on the land. The 

 benefits are most often associated with increased crop yields.(p.24) Gypsum as an agricultural 

 amendment is most applicable to more arid lands, for example Eastern Washington, Eastern 

 Oregon, and parts of Idaho.(EPA 2012c) Given their relative proximity to the Ferndale 

 facility; (perhaps) relatively low transportation costs from the Ferndale facility to a primary 

 farm production facility such as a farmers’ cooperative depot16 in these geographic areas; and 

 the prospect of (relatively) low or lower cost gypsum from Intalco, agricultural applications 

                                                           

14 Mining Applications account for 7.8% of FGD Gypsum production. This was not followed for this review as a

prospective market for Intalco’s syn‐gyp.   15 Again assuming these facilities are not locked into marketing agreements that would preclude purchases of

gypsum from other sources. 16 A quick look at BNSF’s website indicates that the company is able to ship bulk fertilizer. It appears the Ferndale

facility already has one or more rail sidings.  
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

9

 in these areas could provide a prospective market for Intalco’s FGD gypsum. Since Intalco 

 must dispose of its FGD gypsum on a constant amount schedule throughout the year and 

 crops are cyclical, identifying an agricultural market or markets is an issue further study. 

 Intalco’s relatively small annual production may also make it easier for the company to sell 

 to a niche geographic agricultural market. 

 

 U.S.G.S. Derived Statistics

 The following was modified from the U.S.G.S. Gypsum Mineral Commodity Summaries for 

 2012, except where noted. 

 Domestic Production and Use: In 2011, domestic production of crude gypsum was 

 estimated to be 9.4 million metric tons (10,361.6 short tons), with a value of about $65.9 

 million. The leading crude gypsum-producing States were, in descending order, Oklahoma, 

 Texas, Iowa, Nevada, and California, which together accounted for 58% of total output. 

 Overall, 47 companies produced gypsum in the United States at 54 mines and plants in 34 

 States. Approximately 90% of domestic consumption, which totaled approximately 23 

 million metric tons (25.4 short tons) was accounted for by manufacturers of wallboard and 

 plaster products; approximately 1.3 million metric tons (1.4 million short tons) for cement 

 production and agricultural applications, and small amounts of high-purity gypsum for a 

 wide range of industrial processes accounted for the remaining tonnage. At the beginning of 

 2011, the production capacity of operating wallboard plants in the United States was about 

 27 billion square feet1 per year.

Table 1

Gypsum Production, Consumption and Prices 

(1 metric ton = 1.1023 short tons) 

source: U.S.G.S.

 

Salient Statistics—United States: 2007 2008 2009 2010 2011e 

Production (million metric tons): 

 Crude 15,700 12,300 10,400 8,840 9,400 

 Synthetic2

 8,370 9,660 8,120 10,700 11,000 

 Calcined3

 21,700 17,900 13,800 12,100 12,100 

Wallboard products sold (million s.f1) 27,800 20,700 18,300 17,200 16,900 

Imports, crude, including anhydrite 9,390 7,330 4,220 3,330 3,300 

Consumption, apparent4

 33,300 29,100 22,600 22,500 23,400 

Price: 

Average crude, FOB mine, dollars/mt 7.50 8.70 8.50 6.90 7.00 

 FOB mine, dollars/st 6.35 

Average calcined5

, FOB plant, dollars/mt 38.30 42.60 35.00 29.70 30.00 

 FOB plant, dollars/st 34.75 38.65 31.75 26.94 27.22 

Non-calcined synthetic, FOB plant6

, dollars/mt 1 – 3 

 FOB plant, dollars/st 0.91 – 2.72

__________ 

e = Estimated. 

1. The standard unit used in the U.S. wallboard industry is square feet. Multiply square feet by 9.29 x 10-2 to 

 convert to square meters. 

2. Data refer to the amount sold or used, not produced. 

3. From domestic crude and synthetic. 

4. Defined as crude production + total synthetic reported used + imports – exports. 

5. Calcined gypsum contains about 1⁄2 molecule of water; non-calcined about 2 molecules of water. 

6. Estimate provided by U.S.G.S. expert. 
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

10

Intalco’s Cost and Income from FGD Gypsum Disposal or Sale

Assuming Intalco is able to sell its FGD gypsum into the marketplace, and based on the 2011 

FOB prices paid for FGD gypsum in short tons (Table 1), the financial return to Intalco would be 

as follows: 

Table 2

Cost/Income from the Disposal and Sale of Intalco FGD Gypsum 

- Does not include storage and related handling costs - 

 (see Table 1 for prices) 

 Total Annual 

 Syn-gyp cost = - $ 

 Annual Production income = +$

 

Landfill Disposal, dollars per short ton 145 27,000 - $3,915,000 

Sale of Intalco FGD gypsum: 

 FOB Ferndale facility, dollars per short ton 0.00 27,000 $ 0 

 FOB Ferndale facility, dollars per short ton 0.91 27,000 + $24,570 

 FOB Ferndale facility, dollars per short ton 2.72 27,000 + $73,440 

 FOB Ferndale facility, dollars per short ton 27.22 27,000 + $734,94017

Table 2 clearly shows that selling its FGD gypsum at any price, even at zero dollars, is 

preferable to the $3.915 million annual cost Intalco would incur for landfill disposal.18 The 

27,000 tons per year annual production of syn-gyp reflects the Ferndale facility operating all 

three of its potlines at full capacity19. 

Conclusion

This conclusion is based on the best information available at this time. Additional information 

that could have proved useful includes: regional/local gypsum related market costs and prices 

[e.g., transportation costs for shipping Intalco’s FGD gypsum by bulk carrier (rail and road) to 

some representative locations (e.g., Tacoma, Portland, Eastern Washington, Eastern Oregon, 

Idaho, etc.); regional use (consumption) of gypsum; regional market prices for FGD gypsum; 

and a more detailed study of the regional gypsum market related issues (e.g., the type of gypsum 

                                                           

17 Actual income would be less since the costs associated with treating the syn‐gyp to produce calcined syn‐gyp

would have to be taken into consideration. 18 It is recognized that whether Intalco disposes of the syn‐gyp at a landfill or by selling it FOB Ferndale facility,

adequate storage must be available to allow for shipment of the syn‐gyp on a regular schedule. Presumably that

storage cost and the associated costs for loading equipment was included in the consultant’s $145/ton estimate

for disposal, and would be similar when selling the FGD gypsum. These costs are not including in the Table 2

income calculations when the FGD gypsum is sold.     19 It should be noted that aluminum smelting capacity at the Ferndale facility could be reduced, concurrently

reducing the quantity of syn‐gyp produced and Intalco’s disposal costs or sales income – though capital costs

would remain constant.
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

11

preferred by potential buyers). That stated, at this time there appear to be a number of issues that 

point positively to a prospective market for Intalco’s FGD gypsum: 

 Intalco’s estimated annual FGD gypsum production is extremely small compared to 

the overall domestic gypsum market (though it is not known what the total gypsum 

use is within this region, a more realistic indicator). This means Intalco does not have 

to locate buyers who only require suppliers who can provide huge quantities of 

gypsum. 

 Intalco would not necessarily have to sell its FGD gypsum at the general market price 

because Intalco, at a minimum, would be able to sell its syn-gyp at a cost that allows 

it to only cover its on-site handling and storage (i.e., break-even) – or perhaps even at 

a cost lower than $145 per ton. 

 The general market price for FGD gypsum is considerably lower than that for crude 

gypsum, thereby giving FGD gypsum, Intalco’s product, a competitive advantage 

when selling into the market. 

 Calcined gypsum commands significantly more than non-calcined gypsum. This 

could prospectively provide a considerably greater return for Intalco (though it is not 

known at this time if there is a regional market for calcined gypsum, and whether the 

seller or buyer performs the calcination process). 

 The wallboard market is gradually recovering as reflected in the improving housing 

market. 

 Agriculture could provide a real market for Intalco’s FGD gypsum, where that 

agriculture market’s proximity to Ferndale translates into lower transportation costs, 

and Intalco’s ability to provide low priced FGD gypsum could translate into a further 

incentive for farmers to purchase the company’s FGD gypsum. 

 The Ferndale facility already has a railroad siding, i.e., access to the BNSF mainline 

and routes north/south and east. 

 The Ferndale facility is relatively close to I5, facilitating easy road transport as a 

possible shipping method. 

 Other than TransAlta, Intalco appears to be the only prospective supplier of FGD 

gypsum in this region. 

Keeping in mind the caveats previously mentioned, particularly the issues with forecasting and 

the limited local market information, it appears there could be a market or markets for Intalco’s 

FGD gypsum starting about 2017, and that any price Intalco receives from a buyer or buyers, 

even if that buyer only pays for loading and transportation, and maybe not even for loading, 

would substantially reduce the financial burden for Intalco compared to paying for landfill 

disposal costs at or near $145 per ton. 

* * * * * 
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

12

References 

ACAA – American Coal Ash Association. 2010. ACAA CCP Survey Results. Annual surveys 

 available from 2000 through 2010. 

http://acaa.affiniscape.com/displaycommon.cfm?an=1&subarticlenbr=3

ALCOA. 2010. 2010 Annual Report and Form 10-K. 

CFTC – Commodity Futures Trading Commission. 2011. Glossary. 

http://www.cftc.gov/ConsumerProtection/EducationCenter/CFTCGlossary/index.htm

Chen, Liming and Warren A. Dick. 2011. “Gypsum as an Agricultural Amendment: General Use 

 Guidelines”. The Ohio State University. Bulletin 945. 

Environ. 2007. Bart Determination for Alcoa Intalco Works, Ferndale, Washington. ENVIRON 

 Corporation, Emeryville, California. November 2007. 

http://www.ecy.wa.gov/programs/air/globalwarm_RegHaze/BART/

 IntalcoBARTDeterminationFINAL.pdf 

EPA. 2008. Agricultural Uses for Flue Gas Desulfurization (FGD) Gypsum. EPA530-F-08-009. 

 March 2008. 

EPA, 2012a. Email from Zach Hedgpeth to Elliot Rosenberg. 1/23/12, and subsequent 

 conversation. 

EPA. 2012b. Email from Zach Hedgpeth to Elliot Rosenberg. 2/09/12. 

EPA. 2012c. Discussion with Karla Anderson. 

FGDProducts. Org. Developed by the ACAA Educational Foundation and its Partner 

 organizations, this website has been designed to provide production, technical and 

 environmental information about the use of FGD Gypsum 

http://www.fgdproducts.org

Taylor, Michael et al. 2006. Energy Efficiency and CO2 Emissions from the Global Cement 

Industry. IEA, Paris, 4-5 September 2006 

 http://www.iea.org/work/2006/cement/taylor_background.pdf 

Transalta. 2012. 

 http://suppliers.transalta.com/sd2002/enviro_performance/land_use/waste.shtml 

USA Gypsum. 2012. Agricultural Gypsum Uses. 
INTALCO FGD GYPSUM MARKET REVIEW ‐ FINAL

13

U.S.G.S. 2012a. Gypsum Statistics and Information.

http://minerals.usgs.gov/minerals/pubs/commodity/gypsum/

U.S.G.S. 2012b. Other estimates and gypsum market information per phone calls with Robert D. 

 Crangle, Jr., Gypsum Commodity Specialist. 
Attachment 14 – Intalco LSFO Cost Elements Comparison

Cost Element Environ Assumption 

Scrubber	redundancy	 Two	scrubber	towers,	each	capable	of	treating	100%	of	the	

exhaust	gas	stream;	i.e.	full	redundancy	during	scrubber	tower	maintenance.	

A	singlexhaus

Equipment	lifetime	 15	years	 30	yeaGypsum	disposal/reuse	 Landfilled.	 Given	aCapital	equipment	quote	 Average	of	two	quotes,	scaled	from	TN	smelter.	 Lower	Sales	Tax	 6.5%	 8.2%	 Water	cost/usage	 $0.00053/gal	 $0.000

PUD	co

Aquatic	studies	(DNR)	 Not	included.	 $235k7 Cost	Effectiveness	 $7,500/ton	 $4,366
1 Arrows	and	dollar	amounts	indicate	the	approximate	impact	of	each	EPA	assumption	to	increase	or	decr

2	A	single	tower	LSFO	system	will	mean	that	emissions	are	bypassed	during	any	time	the	scrubber	is	offlin

downtime	annually	results	in	approximately	240	tons	less	SO2	removed	by	the	scrubber.	

3	The	EPA	Air	Pollution	Control	Cost	Manual	procedures	require	using	the	actual	expected	life	of	the	contr

Section	1	–	Introduction;	Chapter	2	–	Cost	Estimation:	Concepts	and	Methodology:	

 “For	each	alternative,	calculate	a	discounting	factor	each	year	over	the	life	of	the	equipment...”	(Pa

 “...sufficient	to	finance	the	investment	over	its	entire	life,	using	the	formula...[CRF]...where	PMT	is	

at	an	interest	rate,	i...”	(Page	2‐21,	emphasis	added).	

Wet	flue	gas	desulfurization	(FGD)	scrubbers	can	reasonably	be	expected	to	last	30	years	based	on	the	foll

 "...cost of a project over its lifetime	‐	typically 30 years for a FGD system."		‐‐‐	"Estimating	Costs	of	Air	

1990,	Page	198.	



“Book life – 30 years”	‐‐‐	"Optimum	Values	of	Process	Parameters	of	the	'Wet	Limestone	Flue	Gas	DeChemical	Engineering	&	Technology,	v.	25,	2002.	Pages	427‐432.	

 Footnote	to	cost	calculation	table	for	FGD	systems:		"Book life	‐	30 years; Tax life	‐	20 years"	‐‐‐	"Retr

Plants",	Kaplan,	et	al.,	presented	at	the	1990	Pittsburgh	Coal	Conference,	September	11,	1990.	

 The	following	document	contains	information	on	over	a	dozen	coal	fired	boilers	installed	with	wet	

to	confirm	that	the	vast	majority	of	these	plants	are	still	operating.		"Flue	Gas	Desulfurization	SystePower	Research	Institute	(EPRI),	December	2005.	

4	“Market	Review	for	Intalco	Produced	FGD	Gypsum.”		Elliot	Rosenberg,	Senior	Economist.		EPA	Region	105	Using	the	lowest	responsive	bid	is	based	on:	

 Standard	contracting	practice.	 Both	quotes	were	from	reputable,	experienced	equipment	suppliers.	

 EPA	Air	Pollution	Control	Cost	Manual	supports	using	the	lowest	responsive	bid,		specifically	the	m

multiple	quotes”	(Page	3‐38;	Chapter	3	–	Electrostatic	Precipitators;	Section	6	–	Particulate	Matter	

(Page	1‐29;	Chapter	1	–	Selective	Non‐catalytic	Reduction	(SNCR);	Section	4.2	–	NOX	Post	Combusti

6	Conversation	with	Stephan	Jilk,	General	Manager	of	Whatcom	PUD,	fresh	water	supplier	to	Intalco.	7	Conversations	with	Kyle	Murphy,	Washington	DNR	project	manager	for	Cherry	Point	Aquatic	Reserve	Ma
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION 10

1200 Sixth Avenue

Seattle, WA 98101

December 9, 2011

Reply to

Attn Of: OEA-095

MEMORANDUM

SUBJECT: Intalco Ferndale Smelter BART Review - Scrubber Water Demand

FROM:

Zach Hedg kth,

Environmental Engineer, ESU, OEA

TO: File

On the morning of December 8, 201.1, l called Mr. Stephan !ilk, General Manager of the

Whatcom County Public Utility District, which supplies fresh water to the Intalco

smelter. l explained that the EPA (Region 10 in Seattle) is conducting a review of a

Washington State analysis regarding a potential wet scrubbing air pollution control

system at the Ferndale smelter, I explained that in my technical services role within

Region 10, I was calling to verify the availability of additional freshwater supplies which

would be required by a new scrubbing system, or the lack thflreof.

I explained that the initial designs for the scrubber identify a freshwater requirement of

approximately 0.5 million gallons per day (MGD), and that various reports had claimed

that this additional water would be difficult for Intalco to obtain. I asked Mr. f ilk if he

could verify this scarcity of available water.

Mr. !ilk stated that increasing supply to Intalco by 0.5 MGD would not be a problem for

Whatcom PUD in terms of water availability. Mr. Iilk further explained that provision of

this increased supply would entail the following approximate fees:

• One time "connection charge" to increase the amount of water the PUD delivers

to Intalco of approximately $300,000 based on current charge rates, and

® Ongoing water cost of around $700 per million gallons or approximately $350

per day at 0.5 MGD.