Draft

FACT SHEET FOR NPDES PERMIT WA 0001546

FACILITY NAME TransAlta Centralia Generation LLC

September 2010

PURPOSE of this Fact Sheet

This fact sheet explains and documents the decisions the Department of Ecology (Ecology) made in 

drafting the proposed National Pollutant Discharge Elimination System (NPDES) permit for TransAlta 

Centralia Generation, LLC (TCG). 

The Environmental Protection Agency (EPA) developed the NPDES permitting program as a tool to 

“restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” EPA 

delegated to Ecology the power and duty to write, issue, and enforce NPDES permits within Washington 

State. Both state and federal laws require any industrial facility to obtain a permit before discharging 

waste or chemicals to a water body.

An NPDES permit limits the types and amounts of pollutants the facility may discharge. Those limits are 

based either on (1) the pollution control or wastewater treatment technology available to the industry, or 

on (2) the receiving water’s customary beneficial uses. This fact sheet complies with Section 173-220-

060 of the Washington Administrative Code (WAC), which requires Ecology to prepare a draft permit 

and accompanying fact sheet for public evaluation before issuing an NPDES permit. 

PUBLIC ROLE in the Permit 

Ecology makes the draft permit and fact sheet available for public review and comment at least 30 days 

before issuing the final permit to the facility operator (WAC 173-220-050). Copies of the fact sheet and 

draft permit for TCG, NPDES permit WA001546 are available for public review and comment from June 

9, 2010, until the close of business July 9, 2010. For more details on preparing and filing comments 

about these documents, please see Appendix A - Public Involvement.

Before publishing the draft NPDES permit, TCG, reviewed it for factual accuracy. Ecology corrected any 

errors or omissions about the facility’s location, product type or production rate, discharges or receiving 

water, or its history. 

After the public comment period closes, Ecology will summarize substantive comments and our 

responses to them. Ecology will include our summary and responses to comments to this Fact Sheet as 

Appendix D Response to Comments, and publish it when issuing the final NPDES permit. Ecology will 

not revise the rest of the fact sheet, but the full document will become part of the legal history contained 

in the facility’s permit file. 

Aziz Mahar, P.E., prepared the permit and this fact sheet.
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TABLE OF CONTENTS

I. BACKGROUND INFORMATION ................................................................................................ 4

A. Facility Description............................................................................................................. 5

History ................................................................................................................... 5

Wastewater Treatment ........................................................................................... 6

Solid Waste Management .................................................................................... 11

Discharge Outfalls............................................................................................... 12

B. Permit Status..................................................................................................................... 13

C. Summary of Compliance with Previous Permit Issued .................................................... 13

D. Wastewater Characterization ............................................................................................ 13

E. Description of the Receiving Water.................................................................................. 14

F. SEPA Compliance ............................................................................................................ 14

II. PROPOSED PERMIT CONDITIONS .......................................................................................... 14

A. Design Criteria.................................................................................................................. 15

B. Outfall 001 Technology-Based Effluent Limits................................................................ 15

Outfall 002 Technology-Based Effluent Limits................................................................ 16

C. Surface Water Quality-Based Effluent Limits.................................................................. 17

Numerical Criteria for the Protection of Aquatic Life and Recreation................ 17

Numerical Criteria for the Protection of Human Health...................................... 17

Narrative Criteria ................................................................................................. 18

Antidegradation ................................................................................................... 18

Mixing Zones....................................................................................................... 19

D. Designated Uses and Surface Water Quality Criteria....................................................... 20

E. Evaluation of Surface Water Quality -Based Effluent Limits for Numeric Criteria......... 21

F. Whole Effluent Toxicity ................................................................................................... 23

G. Human Health................................................................................................................... 24

H. Sediment Quality .............................................................................................................. 24

I. Ground Water Quality Limits........................................................................................... 24

J. Comparison of Effluent Limits with Limits of the Previous Permit Issued on 

June 30, 2005 .................................................................................................................... 24

IV. MONITORING REQUIREMENTS.............................................................................................. 26

A. Lab Accreditation ............................................................................................................. 27

V. OTHER PERMIT CONDITIONS ................................................................................................. 27

A. Reporting and Recordkeeping........................................................................................... 27

B. Non Routine and Unanticipated Discharges..................................................................... 27

C. Spill Plan........................................................................................................................... 27

D. Solid Waste Control Plan.................................................................................................. 27

E. Treatment System Operating Plan .................................................................................... 27

F. General Conditions........................................................................................................... 28

VI. PERMIT ISSUANCE PROCEDURES ......................................................................................... 28

A. Permit Modifications ........................................................................................................ 28

B. Proposed Permit Issuance ................................................................................................. 28

VII. REFERENCES FOR TEXT AND APPENDICES........................................................................ 29

APPENDIX A--PUBLIC INVOLVEMENT INFORMATION ................................................................. 30
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APPENDIX B--GLOSSARY ..................................................................................................................... 31

APPENDIX C--COMPLIANCE HISTORY ANDTECHNICAL CALCULATIONS .............................. 35

APPENDIX D--RESPONSE TO COMMENTS ........................................................................................ 45
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INTRODUCTION

The Federal Clean Water Act (FCWA, 1972, and later amendments in 1977, 1981, and 1987) established 

water quality goals for the navigable (surface) waters of the United States. One mechanism for achieving 

the goals of the Clean Water Act is the National Pollutant Discharge Elimination System of permits 

(NPDES permits), administered by the federal Environmental Protection Agency (EPA). The EPA 

authorized the state of Washington to manage the NPDES permit program in our state. Our state 

legislature accepted the delegation and assigned the power and duty for conducting NPDES permitting 

and enforcement to the Department of Ecology (Ecology). The legislature defined Ecology's authority 

and obligations for the wastewater discharge permit program in 90.48 RCW (Revised Code of 

Washington). 

Ecology adopted rules describing how it exercises its authority: 

Procedures Ecology follows for issuing NPDES permits (chapter 173-220 WAC) 

Water quality criteria for surface waters (chapter 173-201A WAC) and for ground waters 

(chapter 173-200 WAC)

Sediment management standards (chapter 173-204 WAC) 

Submission of Plans and Reports for Construction of Wastewater Facilities (chapter 173-240 

WAC)

These rules require any industrial facility operator to obtain an NPDES permit before discharging 

wastewater to state waters. They also help define the basis for limits on each discharge and for 

performance requirements imposed by the permit. 

Under the NPDES permit program and in response to a complete and accepted permit application

Ecology must prepare a draft permit and accompanying fact sheet, and make them available for public 

review before final issuance. Ecology must also publish an announcement (public notice) telling people 

where they can read the draft permit, and where to send their comments, during a period of thirty days 

(WAC 173-220-050). (See Appendix A--Public Involvement for more detail about the Public Notice 

and Comment procedures). After the Public Comment Period ends, Ecology may make changes to the 

draft NPDES permit in response to comments. Ecology will summarize the responses to comments and 

any changes to the permit in Appendix D.

I. BACKGROUND INFORMATION

Table 1 - General Facility Information

Applicant: TransAlta Centralia Generation, LLC

Facility Name and Address:

TransAlta Centralia Generation, LLC

913 Big Hanford Road

Centralia, WA98531

Type of Treatment:

Outfall 001: Coal Pile Runoff - Settling Pond

Stormwater Runoff - Settling Pond

Cooling Tower Blowdown – Settling Pond

Outfall 002 (Sanitary Effluent)– Activated Sludge, 

Oxidation Ditch and Disinfection
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SIC Code 4911 – Electric Power Generation

Discharge Location: Hanaford Creek

Figure 1. Facility Location Map – TransAlta Power Plant

A. Facility Description

History

The TCG, a wholly owned subsidiary of TransAlta Corporation, operates a coal-fired electricity 

generating power plant located approximately six miles northeast of Centralia, Washington. TCG 

operations consist of two, 702.5 Megawatt turbine units that are fueled by coal supplied from out of state 

coal providers located in the Powder River Basin on the Montana/Wyoming border. In addition, TCG 

operates a 250 Megawatt natural gas power plant on the same site utilizing four gas turbine engines and a 

single heat recovery steam generator. The TCG has operated continuously since 1971 with no significant 

alteration. Ecology and EPA classify it as a NPDES major facility. 

Electricity demand typically peaks in the winter and the plant occasionally shutdowns in the spring and 

summer when electricity demand is low. TCG uses these periods to maintain the facility. When 

operating conditions are ideal, the facility generates electricity continuously for months at a time. TCG 

employs approximately 325 employees. Operations personnel work two 12-hour shifts, other personnel 
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(administrative) work 8-hour shifts on regular Monday through Friday business hours, and maintenance 

personnel work 10-hour shifts Monday through Thursday.

Industrial Process

TCG generates electrical power by burning coal mined in Montana and Wyoming. TCG utilizes its two 

boiler units to generate 1,405,000 kilowatts of electrical power per hour, typically totaling between 

7,000,000 and 12,000,000 megawatt hours per year. TCG uses approximately 26,000,000 gallons of 

water per day when operating. Approximately 17,250,000 gallons per day evaporates as the water cools

the steam-electric generating process. TCG uses approximately 2,000,000 gallons per day for air 

pollution control in the current Wet Flue Gas Desulfurization (WFGD) (also referred as scrubber) 

operations. 

TCG draws water for this operation from the Skookumchuck River and the process water discharges to

the Hanaford Creek. Domestic sewage is also generated on the TransAlta site both at the TCG and the 

TransAlta Centralia Mining (TCM) facility adjacent to the power plant. Table 2 summarizes wastewater 

generation.

Table 2 - Wastewater Generation

Source Approximate Discharge, MGD

Sanitary Effluent 0.01

Scrubber wastewater 0.04

Coal pile stormwater runoff 0.5

Plant stormwater runoff 0.4

Cooling tower blowdown 2.4

Water Treatment 

TCG owns and operates its own water treatment plant. Intake water is drawn from the Skookumchuck 

River at a rate of 26 MGD. The facility pumps intake water to the surge pond (Figure 3), then treats it 

with filtration, deionization, and reverse osmosis and then uses it for all power plant and potable water 

demands. 

Wastewater Treatment

A. General Description

TCG treats the coal pile stormwater runoff (CPRO) using flocculation and settling. Sanitary effluent is 

treated by the activated sludge process. TCG treats its stormwater runoff and cooling tower blowdown in 

lagoons in the winter; however, during the summer, it treats these wastewater streams by discharging the 

water to pond 3E and/or reusing it in the Wet Flue Gas Desulfurization (WFGD) (Figure 3) scrubbers. 
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Figure 2. Wastewater Treatment System Network
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B. Wastewater Treatment Procedure

1. Oil Skimmer Pond

TCG uses this 130,000-gallon pond to contain any floating oil or other floating debris from potentially oil 

contaminated areas. The areas that drain to this pond include:

Plant floor drains

Transformer basin drains

Fuel oil and lube oil storage basin drains

Compressor building sump pump drains

Demineralizer neutralization tank drain

Turbine bay sumps

2. South Effluent Pond

The following areas drain to this 5,000,000-gallon pond.

Circulating water cooling tower blowdown

Units 1 and 2 boiler drains

BHP facilities

Air pre-heater wash drains

Cooling tower basin drains

Circulating water system drains

Bottom ash system surge tank overflows

Ultra-pure water treatment plant

3. North Effluent Pond

This pond has a nominal capacity of 3,000,000 gallons. Water passes through a sub-surface culvert from 

the south effluent pond to the north effluent pond. Due to the fact that this culvert is below the normal 

water level, and is further protected by a floating boom, all floating material is effectively trapped in the 

south pond. In addition, the pond’s detention time allows most of the suspended solids adequate time to 

settle out in the south pond. TCG reuses the North Effluent Pond water for:

The plant fire protection system – the primary sources of fire system water are the north effluent 

pond wastewater pumps and the wastewater booster pumps (which are located on the south side 

of unit 2).
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Bottom ash system make-up.

Fly ash bin yard drain wash water.

Dilution water for the CPRO chemicals.

Wash-down water.

In the event wastewater levels exceed safe pond capacity, provision is made to dispose of excess 

wastewater by pumping to the coal pile runoff (CPRO) treatment ponds. 

4. Wastewater Pumping Systems 

TCG uses the following pumping systems to direct wastewater:

North Effluent Pond wastewater pumps – Located just outside (south) of the north effluent pond 

pump house

Two wastewater pumps rated at 3,000 gallons per minute (gpm) and provide wastewater for most 

plant processes 

One north effluent pond irrigation pump rated at 3,000 gpm and used to pump wastewater to the 

wastewater system 

5. Sewage (Domestic wastewater) Treatment Train 

TCG operates a small, packaged, activated sludge sewage treatment plant designed for a maximum flow 

rate of 36,000 gallons per day. This extended aeration, activated sludge; secondary treatment plant 

handles normal plant sewage from the TCG, Big Hanaford Project (BHP) and the TransAlta Centralia 

Mining (TCM) facilities. This process consists of four major components:

Raw sewage pump house

Treatment plant

Oxidation pond

Chlorination contact chamber

Raw sewage flows by gravity into the sump under the floor of the pump house and activates one of the 

two lift pumps. Sewage is pumped through a splitter gate which allows approximately 20 percent of the 

flow to enter the treatment plant and recycles 80 percent back into the sump. This allows a relatively 

steady flow to enter the plant rather than a series of heavy, or “shock loads”.

From the splitter gate, the sewage flows into the aeration basin where diffused air is introduced at timed 

intervals producing O2 level high enough to sustain aerobic bacteria present in the sewage. 

From the aeration basin, the sewage flows into the clarifier where the heavy floc formed in the aeration 

basin readily settle to the bottom and the clear, “treated”, supernatant discharges to the oxidation pond. 
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The settled floc, or sludge, is then returned by a sump system from the bottom of clarifier back to the 

aeration basin where it re-mixes with incoming sewage. 

The oxidation pond serves a two-fold purpose. Its approximate ten day retention period allows the O2

level of the treated sewage to increase to a level more acceptable for discharge into a receiving stream. In 

addition, it provides a buffer zone for any occasional plant upsets that may allow heavier solid materials 

to escape from the clarifier.

TCG treats the effluent from the oxidation pond with sodium hypochlorite to remove any possible 

disease-carrying bacteria before ultimate discharge into Hanaford Creek. Retention time in the chlorine 

contact chamber is approximately 6 to 8 hours. Effluent from the chlorine contact chamber enters the 

CPRO ditch and flows to the series of CPRO ponds before final discharge into Hanaford Creek.

6. CPRO Operation

TCG contains runoff from the coal storage area within a system of dikes and directs it through a series of 

ponds for treatment to remove suspended solids before discharge into Hanaford Creek. In addition to 

water coming directly from the coal pile, sewage treatment plant effluent and yard drains from other areas

within the plant drain to this outfall. The primary treatment method for the CPRO system consists of 

flocculation by the addition of aluminum sulfate and polymer. 

Aluminum sulfate is pumped directly from the bulk storage tank to the culvert inlet next to the CPRO 

pump house. Laboratory personnel determine and set the correct pump stroke. Anionic or Cationic 

polymer is added at the mixing box located between the CPRO pump house and Hanaford Creek. This 

treatment makes larger and heavier floc particles, which then settles in the CPRO pond system. 

7. Discharge to Mine Pond 3E

When the CPRO pond temperature rises due to ambient air temperatures, such that the facility cannot 

meet the Outfall 001 temperature requirements, it pumps this wastewater from the north effluent pond to 

Mine Pond 3E and/or the WFGD and conducts the applicable monitoring. 

Solid Waste Management

Below is a listing and description of solid waste generated by TCG:

Recyclables

Scrap Steel –Steel is collected from around the site in specially marked “scrap steel” recycling bins and 

are then aggregated into large dumpsters. Due to maintenance activities, the amount of the scrap metal 

recycled annually varies significantly but can be as much as 174 tons recycled in 2007. 

 

Office Paper/Cardboard – TCG recycles office paper and card boards in marked containers located in 

all office spaces and in the warehouse. Although estimated at over 75 percent recycled, vendor recycling 

this material does not supply TCG with a mass of the recycled materials.

Plastics and Metals - TCG has recently started recycling spent plastic (water bottles, etc) as well as 

aluminum cans. TCG has not started accounting for this material on a mass basis for tracking and 

reporting.

Tires – All tires are recycled through TCG’s tire suppliers. 
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Other – Spent chemicals and oil and containers are all recycled with the product manufacturers. Many 

manufacturers hold a “deposit” for container which acts an incentive for recycling.

Standard Solid Waste Refuse

TCG aggressively pursues opportunities to re-use and recycle solid wastes. Many wastes still require off 

-site disposal and are wastes common to households, municipalities and businesses. They consist of 

packaging containers, non-recyclable plastic and rubber material etc. All solid wastes are collected within 

TCG physical boundary, where it collects and monitors all stormwater and wastewater for contaminants, 

and treats as necessary prior to discharge. 

Sludge Disposal

Sludge disposal at TCG consists of three main types: 

Sewage treatment plant sludge 

CPRO sludge 

Effluent pond cleaning sludge

Sewage Treatment Plant Sludge 

A local contractor disposes of the normal operational sludge and its volume averages 3,000 to 5,000 

gallons per quarter. As needed, the facility performs a general sewage treatment plant cleaning.

CPRO Sludge Disposal

The facility currently disposes of the CPRO sediment by pumping it with a floating dredge and booster 

pumps to a dewatering pond on the east appendage of the coal pile.

Effluent Pond Cleaning 

TCG uses the wastewater from the north effluent pond for various plant processes. The largest portion is 

used in ash handling systems. Overflow from the ash system returns to the south effluent pond. This 

constitutes the major source of the settable suspended solids in the effluent ponds. Another source of 

solids is silt from various yard drains. TCG periodically removes these solids using a floating dredge and 

dewaters the waste using the same method as for the CPRO sediment. The total volume of sediment 

handled varies, but it ranges from 5,000 to 10,000 cubic yards per year.

DISCHARGE OUTFALLS

This NPDES permit authorizes wastewater discharge through two outfalls (Outfalls 001 and 002). 

Outfall 001 -The list below identifies the sources of discharge through outfall 001: 

Outfall 002 (domestic wastewater effluent)

South and north effluent ponds
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Coal pile runoff 

The discharge flows for the TCG are conveyed through various drains and pipe lines from the TCG 

facility to a series of settling ponds. The CPRO treatment ponds are the confluence of the north and the 

south pond system. The cooling tower blow down, coal pile runoff, site stormwater runoff and treated 

sanitary wastewater flows during the wet season operations. The CPRO ponds are divided by berms and 

curtains into eight cells. The final cell discharges to the monitoring station (parshall flume) and then Big

Hanford Creek. 

Outfall 002-TCG designed this internal outfall to monitor the quality of domestic waster (Sanitary 

sewage) system, with a rated capacity of 20,000 gallons per day (30-day average). The wastewater 

through this outfall combines with the outfall 001 discharge at the CPRO treatment collection box. 

B. Permit Status

TCG submitted an application for permit renewal on January 27, 2009. Ecology accepted it as complete 

on February 3, 2009.

C. Summary of Compliance with Previous Permit Issued

Ecology staff last conducted a non- sampling compliance inspection on December 4, 2008. 

TCG for the most part has complied with the effluent limits and permit conditions throughout the duration 

of the permit issued on June 30, 2005. There were a number of exceptions in which TCG failed to 

comply with the permit requirements. Ecology assessed facility compliance based on its review of the

facility’s Discharge Monitoring Reports (DMRs) and inspections conducted by Ecology. The permit 

violations are appended in appendix C of this fact sheet.

D. Wastewater Characterization

The concentration of pollutants in the discharge was reported in the NPDES application and in discharge 

monitoring reports. The tabulated data represents the quantity and quality of the effluent discharged 

during the time period of July 1, 2005, through February 2010. The following statistical analysis shows 

that the Permittee, for the most part, has remained within the permit limits. 

Table 3: Outfall 001 discharge characteristics, Discharge to Hanaford Creek

Combined domestic and process wastewater discharge

Parameter Minimum Maximum Average Median No. of data 

points

Permit 

limit, 

maximum

Flow, MGD 0.56 8 3.57 3.3 39 12.12

Total Residual Chlorine, 

mg/L 0.00 0.87 0.095 0.04 39 0.20

Oil and Grease, mg/L 2 2.4 2.066 2 6 20

Total Suspended Solids, 

mg/L 1.5 36.7 7.143 4.8 39 100

Chromium, Total, mg/L 0.007 0.009 0.0074 0.007 5 0.2
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Combined domestic and process wastewater discharge

Parameter Minimum Maximum Average Median No. of data 

points

Permit 

limit, 

maximum

Zinc, mg/L 0.001 0.02 0.008 0.006 5 1

Dissolved Oxygen, mg/L 8.25 13.7 10.61 10.60 39 8

(minimum)

Temperature, Background,

oC 3.95 18 9.65816 8.9 49 N/A

Turbidity, Background, NTU 1.3 50 12.09 9.32 54 N/A

Table 4- Domestic wastewater discharge characteristics

Outfall 002 – Domestic wastewater discharge

Parameter Minimum Maximum Average Median No. of data 

points

Permit 

Limit

(maximum)

Flow, MGD 0.006 0.0251 0.0133 0.0130 56 0.036

BOD, mg/L 2 142 17.2 8 56 45

TSS, mg/L 0.4 36.8 11.4 10.2 56 45

Total Residual Chlorine , 

mg/L

0.5 3.5 1.425 1.45 45 2.0

Fecal Coliform #/100mL 0 336 41 4.5 56 400

E. Description of the Receiving Water

TCG discharges to Hanaford Creek. Other nearby point-sources outfalls include, TransAlta Centralia 

Mining and Limited Purpose Landfill discharges. Significant nearby non-point sources of pollutants are 

not known. 

F. SEPA Compliance

Regulation exempts reissuance or modification of any wastewater discharge permit from the SEPA 

process as long as the permit contains conditions are no less stringent than state rules and regulations. 

The exemption applies only to existing discharges, not to new discharges. 

II. PROPOSED PERMIT CONDITIONS

Federal and state regulations require that effluent limits in an NPDES permit must be either technology or 

water quality-based.

Technology-based limits are based upon the treatment methods available to treat specific 

pollutants. Technology-based limits are set by the EPA and published as a regulation, or Ecology 

develops the limit on a case-by-case basis (40 CFR 125.3, and chapter 173-220 WAC). 
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Water quality-based limits are calculated so that the effluent will comply 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 (40 CFR 

131.36). 

Ecology must apply the most stringent of these limits to each parameter of concern. These limits 

are described below.

The limits in this permit reflect information received in the application and from supporting reports 

(engineering, hydrogeology, etc.). Ecology evaluated the permit application and determined the limits 

needed to comply with the rules adopted by the state of Washington. Ecology does not develop effluent 

limits for all reported pollutants. Some pollutants are not treatable at the concentrations reported, are not 

controllable at the source, are not listed in regulation, and do not have a reasonable potential to cause a 

water quality violation. 

Nor does Ecology usually develop permit limits for pollutants that were not reported in the permit 

application but that may be present in the discharge. The permit does not authorize discharge of the nonreported pollutants. During the five-year permit term, the facility’s effluent discharge conditions may 

change from those conditions reported in the permit application. The facility must notify Ecology, as 

described in 40 CFR 122.42(a), if significant changes occur in any constituent. Industries may be in 

violation of their permit until Ecology modifies the permit to reflect additional discharge of pollutants.

A. Design Criteria

According to WAC 173-220-150 (1)(g), neither flows nor waste loadings may exceed approved design 

criteria, however, Ecology does not have an engineering report that specifies the design criteria for the 

wastewater treatment plant at this facility. 

B. Technology-Based Effluent Limits

The applicable federal code for this type of discharge (outfall 001) is 40 Code of Federal Regulations 

(CFR) 423. This code, 40 CFR 423, states the following: 

“423.13 Effluent limitations guidelines representing the degree of effluent reduction attainable by the 

application of the best available technology economically achievable (BAT).

Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this part must 

achieve the following effluent limitations representing the degree of effluent reduction attainable by the 

application of the best available technology economically achievable (BAT).

(a) There shall be no discharge of polychlorinated biphenyl compounds such as those commonly used for 

transformer fluid.

(d)(1) The quantity of pollutants discharged in cooling tower blowdown shall not exceed the quantity 

determined by multiplying the flow of cooling tower blowdown times the concentration listed below:

Table 5- Cooling Tower Blowdown BAT Limits

Pollutant or pollutant property

BAT effluent limitations

Maximum Average concentration (mg/L)
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concentration 

(mg/L)

Free available chlorine 0.5 0.2

Pollutant or pollutant property

Maximum for any 1 

day −(mg/L)

Average of daily values for 30 

consecutive days shall not exceed 

=(mg/L)

The 126 priority pollutants contained in 

chemicals added for cooling tower 

maintenance, except:

(

1

) (

1

)

Chromium, total 0.2 0.2

Zinc, total 1.0 1.0

1No detectable amount.

(2) Neither free available chlorine nor total residual chlorine may be discharged from any unit for more 

than two hours in any one day and not more than one unit in any plant may discharge free available or 

total residual chlorine at any one time unless the utility can demonstrate to the Regional Administrator or 

State, if the State has NPDES permit issuing authority, that the units in a particular location cannot 

operate at or below this level of chlorination.

(3) At the permitting authority's discretion, instead of the monitoring specified in 40 CFR 122.11(b)

compliance with the limitations for the 126 priority pollutants in paragraph (d)(1) of this section may be 

determined by engineering calculations which demonstrate that the regulated pollutants are not 

detectable in the final discharge by the analytical methods in 40 CFR part 136.”

Outfall 002

TCG has also domestic wastewater treatment plant and the applicable Code of Federal Regulation (CFR) 

and Washington Administrative Code (WAC) are the following:

Technology-Based Effluent Limits

Federal and state regulations define technology-based effluent limits for municipal wastewater treatment 

plants. These effluent limits are given in 40 CFR Part 133 (federal) and in chapter 173-221 WAC. These 

regulations are performance standards that constitute all known, available, and reasonable methods of 

prevention, control, and treatment (AKART) for municipal wastewater. Chapter 173-221 WAC lists the 

following technology-based limits for pH, fecal coliform, BOD5, and TSS: 

Table 6:Technology-based Limits for Outfall 002.

Parameter Limit

pH The pH must measure within the range of 6.0 to 9.0 standard units.

Fecal Coliform Bacteria Monthly Geometric Mean = 200 organisms/100 mL

Weekly Geometric Mean = 400 organisms/100 mL
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Parameter Limit

BOD5

(concentration)

Average Monthly Limit is the most stringent of the following:

- 30 mg/L

- may not exceed fifteen percent (15 percent) of the average

- influent concentration 

Average Weekly Limit = 45 mg/L

TSS

(concentration)

Average Monthly Limit is the most stringent of the following:

- 30 mg/L

- may not exceed fifteen percent (15 percent) of the average

- influent concentration

Average Weekly Limit = 45 mg/L

Chlorine Average Monthly Limit = 2.0 mg/L

Maximum Daily Limit = 2.0 mg/L

The existing permit has a chlorine limit of 2.0 mg/L for outfall 002 and the facility is able to comply with 

it. The proposed permit includes the same limit. This chlorine limit is higher than the technology based 

and water quality based limits due to the fact that at this outfall 002, the Permittee is not directly 

discharging their wastewater to the surface water. This outfall 002 is discharging to outfall 001 which 

does go to the surface water. The chlorine limit will change at outfall 001 to a stricter limit of 0.2 mg/L.

The technology-based mass limits are based on WAC 173-220-130(3)(b) and 173-221-030(11)(b). 

Monthly effluent mass loadings for both BOD5 and TSS (lbs/day) = maximum monthly design flow 

(0.036MGD) x Concentration limit (30 mg/L) x 8.34 (conversion factor) = mass limit 9.0 lb/day.

The weekly average effluent mass loading = 1.5 x monthly loading = 13.5 lbs/day.

C. Surface Water Quality-Based Effluent Limits

The Washington State Surface Water Quality Standards (chapter 173-201A WAC) were designed to 

protect existing water quality and preserve the beneficial uses of Washington's surface waters. Waste 

discharge permits must include conditions that ensure the discharge will meet established surface water 

quality standards (WAC 173-201A-510). Water quality-based effluent limits may be based on an 

individual waste load allocation or on a waste load allocation developed during a basin wide total 

maximum daily loading study (TMDL).

Numerical Criteria for the Protection of Aquatic Life and Recreation

Numerical water quality criteria are published in the Water Quality Standards for Surface Waters (chapter 

173-201A WAC). They specify the levels of pollutants allowed in receiving water to protect aquatic life

and recreation in and on the water. Ecology uses numerical criteria 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 

limits, the discharge must meet the water quality-based limits.

Numerical Criteria for the Protection of Human Health 
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The U.S. EPA has published 91 numeric water quality criteria for the protection of human health that are 

applicable to dischargers in Washington State (40 CFR 131.36). These criteria are designed to protect 

humans from exposure to pollutants linked to cancer and other diseases, based on consuming fish and 

shellfish and drinking contaminated surface waters. The Water Quality Standards also include 

radionuclide criteria to protect humans from the effects of radioactive substances.

Narrative Criteria

Narrative water quality criteria (e.g., WAC 173-201A-240(1); 2006) limit the toxic, radioactive, or other 

deleterious material concentrations that the facility may discharge to levels below those which have the 

potential to:

Adversely affect designated water uses.

Cause acute or chronic toxicity to biota.

Impair aesthetic values.

Adversely affect human health. 

Narrative criteria protect the specific designated uses of all fresh waters (WAC 173-201A-200, 2006) and 

of all marine waters (WAC 173-201A-210,; 2006) in the State of Washington.

Antidegradation 

The purpose of Washington's Antidegradation Policy (WAC 173-201A-300-330; 2006) is to:

Restore and maintain the highest possible quality of the surface waters of Washington.

Describe situations under which water quality may be lowered from its current condition.

Apply to human activities that are likely to have an impact on the water quality of surface water.

Ensure that all human activities likely to contribute to a lowering of water quality, at a minimum, 

apply all known, available, and reasonable methods of prevention, control, and treatment 

(AKART).

Apply three Tiers of protection (described below) for surface waters of the state. 

Tier I ensures existing and designated uses are maintained and protected and applies to all waters 

and all sources of pollutions. Tier II ensures that waters of a higher quality than the criteria 

assigned are not degraded unless such lowering of water quality is necessary and in the overriding 

public interest. Tier II applies only to a specific list of polluting activities. Tier III prevents the 

degradation of waters formally listed as "outstanding resource waters," and applies to all sources 

of pollution.

A facility must prepare a Tier II analysis when all three of the following conditions are met: 

The facility is planning a new or expanded action.

Ecology regulates or authorizes the action.
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The action has the potential to cause measurable degradation to existing water quality at the edge 

of a chronic mixing zone. 

This facility must meet Tier I requirements. 

Dischargers must maintain and protect existing and designated uses. Ecology may not allow any 

degradation that will interfere with, or become injurious to, existing or designated uses, except as 

provided for in chapter 173-201A WAC. 

For waters that do not meet assigned criteria, or protect existing or designated uses, Ecology will 

take appropriate and definitive steps to bring the water quality back into compliance with the 

water quality standards. 

Whenever the natural conditions of a water body are of a lower quality than the assigned criteria, 

the natural conditions constitute the water quality criteria. Where water quality criteria are not 

met because of natural conditions, human actions are not allowed to further lower the water 

quality, except where explicitly allowed in this chapter.

Ecology’s analysis described in this fact sheet demonstrates that the existing and designated uses of the 

receiving water will be protected under the conditions of the proposed permit. 

Mixing Zones

A mixing zone is the defined area in the receiving water surrounding the discharge port(s), where 

wastewater mixes with receiving water. Within mixing zones the pollutant concentrations may exceed 

water quality numeric criteria, so long as the diluting wastewater doesn’t interfere with designated uses of 

the receiving water body (e.g., recreation, water supply, and aquatic life and wildlife habitat, etc.). The 

pollutant concentrations outside of the mixing zones must meet water quality numeric criteria. 

State and federal rules allow mixing zones because the concentrations and effects of most pollutants 

diminish rapidly after discharge, due to dilution. Ecology defines mixing zone sizes to limit the amount 

of time any exposure to the end-of-pipe discharge could harm water quality, plants, or fish.

The state’s water quality standards allow Ecology to authorize mixing zones for the facility’s permitted 

wastewater discharges only if those discharges already receive all known, available, and reasonable 

methods of prevention, control and treatment (AKART). Mixing zones typically require compliance with 

water quality criteria within a specified distance from the point of discharge; and use no more than 25

percent of the available width of the water body for dilution. Ecology uses modeling to estimate the

amount of mixing within the mixing zone and determine the potential for violating the water quality 

standards at the edge of the mixing zone and derive any necessary effluent limits. Steady-state models are 

the most frequently used tools for conducting mixing zone analyses. Ecology chooses values for each 

effluent and for receiving water variables that correspond to the time period when the most critical 

condition is likely to occur (see Ecology’s Permit Writer’s Manual). Each critical condition parameter 

(by itself) has a low probability of occurrence and the resulting dilution factor is conservative. The term 

“reasonable worst-case” applies to these values.

The mixing zone analysis produces a numerical value called a dilution factor (DF). A dilution factor 

represents the amount of mixing of effluent and receiving water that occurs at the boundary of the mixing 

zone. For example, a dilution factor of 10 means the effluent comprises 10 percent by volume and the 

receiving water comprises 90 percent of the total volume at the boundary of the mixing zone. Ecology 

uses dilution factors with the water quality criteria to calculate reasonable potentials and effluent limits. 
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Water quality standards include both aquatic life-based criteria and human health-based criteria. The 

former are applied at both the acute and chronic mixing zone boundaries; the latter are applied only at the 

chronic boundary. The concentration of pollutants at the boundaries of any of these mixing zones may 

not exceed the numerical criteria for that zone. 

Each aquatic life acute criterion is based on the assumption that organisms are not exposed to that 

concentration for more than one-hour and more often than one exposure in three years. Each aquatic life 

chronic criterion is based on the assumption that organisms are not exposed to that concentration for 

more than four consecutive days and more often than once in three years. 

The two types of human health-based water quality criteria distinguish between those pollutants linked to 

non-cancer effects (non-carcinogenic) and those linked to cancer effects (carcinogenic). The human 

health-based water quality criteria incorporate several exposure and risk assumptions. These assumptions 

include:

A 70-year lifetime of daily exposures.

An ingestion rate for fish or shellfish measured in kg/day.

An ingestion rate of two liters/day for drinking water

A one-in-one-million cancer risk for carcinogenic chemicals.

The water quality standards impose certain conditions before allowing the discharger a mixing zone. This 

permit does not authorize a mixing zone.

D. Designated Uses and Surface Water Quality Criteria

Applicable designated uses and surface water quality criteria are defined in chapter 173-201A WAC. In 

addition, the U.S. EPA set human health criteria for toxic pollutants (40 CFR 131.36). Criteria applicable 

to this facility’s discharge are summarized below in Table 7.

Aquatic Life Uses are designated based on the presence of, or the intent to provide protection for, 

the key uses. All indigenous fish and non-fish aquatic species must be protected in waters of the 

state in addition to the key species. The Aquatic Life Uses for this receiving water are identified 

below.

Table: 7 Aquatic Life Uses & Associated Criteria

Core Summer Salmonid Habitat

Temperature Criteria – Highest 7DAD MAX 16°C (60.8°F)

Dissolved Oxygen Criteria 9.5 mg/L

Turbidity Criteria • 5 NTU over background when the background is 

50 NTU or less; or 

• A 10 percent increase in turbidity when the 

background turbidity is more than 50 NTU

Total Dissolved Gas Criteria Total dissolved gas shall not exceed 110 percent of 

saturation at any point of sample collection
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pH Criteria pH shall be within the range of 6.5 to 8.5, with a 

human-caused variation within the above range of 

less than 0.2 units

The recreational uses are extraordinary primary contact recreation, primary contact recreation, 

and secondary contact recreation. The recreational uses for this receiving water are identified 

below.

Table 8 Recreational Uses & Associated Criteria

Recreational use Criteria

Primary Contact 

Recreation

Fecal coliform organism levels must not exceed a geometric mean value of 100 

colonies /100 mL, with not more than 10 percent of all samples (or any single 

sample when less than ten sample points exist) obtained for calculating the 

geometric mean value exceeding 200 colonies /100 mL

The water supply uses are domestic, agricultural, industrial, and stock watering.

The miscellaneous fresh water uses are wildlife habitat, harvesting, commerce and navigation, 

boating, and aesthetics.

E. Evaluation of Surface Water Quality -Based Effluent Limits for Numeric Criteria

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 biological oxygen demand (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.

With technology-based controls (AKART), the limits are higher than the water quality criteria limits for

chromium and chlorine. Given an analysis of the past five years of data, this showed that if there would 

have been water quality based limits; the Permittee would have exceeded those limits for these two

pollutants. In this proposed NPDES permit, Ecology requires the Permittee to continue to have the 

technology based limits for this permit cycle but within five years they must submit a plan and report to 

meet the water quality and technology based limits (see S11. special condition of this permit). 

Temperature--The state temperature standards (WAC 173-201A-200-210 and 600-612) include multiple 

elements:

Annual summer maximum threshold criteria (June 15 to September 15)

Supplemental spawning and rearing season criteria (September 15 to June 15)

Incremental warming restrictions

Protections against acute effects

Ecology evaluates each criterion independently to determine reasonable potential and derive permit 

limits. 

Annual summer maximum and supplementary spawning/rearing criteria
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Each water body has an annual maximum temperature criterion [WAC 173-201A-200(1) (c), 210(1)(c), 

and Table 602]. These threshold criteria (e.g., 12, 16, 17.5, 20°C) protect specific categories of aquatic 

life by controlling the effect of human actions on summer temperatures. 

Some waters have an additional threshold criterion to protect the spawning and incubation of salmonids 

(9°C for char and 13°C for salmon and trout) [WAC 173-201A-602, Table 602]. These criteria apply 

during specific date-windows.

The threshold criteria apply at the edge of the chronic mixing zone. Criteria for most fresh waters are 

expressed as the highest 7-Day average of daily maximum temperature (7-DADMax). The 7-DADMax 

temperature is the arithmetic average of seven consecutive measures of daily maximum temperatures. 

Criteria for marine waters and some fresh waters are expressed as the highest 1-Day annual maximum 

temperature (1-DMax). 

Incremental warming criteria

The water quality standards limit the amount of warming human sources can cause under specific 

situations [WAC 173-201A-200(1)(c)(i)-(ii), 210(1)(c)(i)-(ii)]. The incremental warming criteria apply at 

the edge of the chronic mixing zone.

At locations and times when background temperatures are cooler than the assigned threshold criterion, 

point sources are permitted to warm the water by only a defined increment. These increments are 

permitted only to the extent doing so does not cause temperatures to exceed either the annual maximum 

or supplemental spawning criteria.

At locations and times when a threshold criterion is being exceeded due to natural conditions, all human 

sources, considered cumulatively, must not warm the water more than 0.3°C above the naturally warm 

condition. 

When Ecology has not yet completed a TMDL, our policy allows each point source to warm water at the 

edge of the chronic mixing zone by 0.3°C. This is true regardless of the background temperature and 

even if doing so would cause the temperature at the edge of a standard mixing zone to exceed the numeric 

threshold criteria. Allowing a 0.3°C warming for each point source is reasonable and protective where 

the dilution factor is based on 25 percent or less of the critical flow. This is because the fully mixed effect 

on temperature will only be a fraction of the 0.3°C cumulative allowance (0.075°C or less) for all human 

sources combined. 

Temperature Acute Effects

Instantaneous lethality to passing fish: The upper 99th percentile daily maximum effluent temperature 

must not exceed 33°C; unless a dilution analysis indicates ambient temperatures will not exceed 33°C 2-

seconds after discharge.

General lethality and migration blockage: Measurable (0.3°C) increases in temperature at the edge of 

a chronic mixing zone are not allowed when the receiving water temperature exceeds either a 1DMax of 

23°C or a 7DADMax of 22°C.

Lethality to incubating fish: Human actions must not cause a measurable (0.3°C) warming above 

17.5°C at locations where eggs are incubating. 
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Turbidity--The permit requires turbidity monitoring to assess compliance with the water quality criteria 

for turbidity (see Table 8) because of potential fluctuations in turbidity of both the receiving water and the 

effluent. 

Toxic Pollutants--Federal regulations (40 CFR 122.44) require Ecology to place limits in NPDES 

permits on toxic chemicals in an effluent whenever there is a reasonable potential for those chemicals to 

exceed the surface water quality criteria. Ecology does not exempt facilities with technology-based 

effluent limits from meeting the surface water quality standards. Generally federal discharge limits are 

more stringent than surface water quality standards, except zinc, chromium and total residual chlorine, for 

this type of discharge. 

40 CFR 423 requires that the Permittee must achieve non- detectable levels for the priority pollutants 

(priority pollutant less chromium and zinc) for the cooling tower blow down discharge before this water is 

discharged to the surface water (Hanaford Creek). This NPDES permit requires the Permittee to conduct 

and submit a priority pollutant analysis report once per permit cycle. Ecology received an electronic copy 

of the priority pollutant analysis report on April 13, 2010. This report showed that the Permittee has met 

the non detectable requirement for all priority pollutants except for the following parameters: Arsenic, 

Copper, Lead, Nickel, Selenium and Zinc. 

Ecology conducted a reasonable potential analysis (See Appendix C) on chlorine, chromium, arsenic and 

selenium parameters to determine whether it would be necessary to require effluent limits in this permit. 

The reasonable potential analysis showed that there is no reasonable potential that the Permittee would 

exceed the water quality criteria for arsenic. But this analysis did show that there was a reasonable 

potential that the Permittee would exceed the water quality criteria for chlorine, chromium and selenium. 

There were some parameters such as copper, lead, nickel and zinc which Ecology was unable to 

determine the reasonable potential that the Permittee would exceed the water quality criteria because of 

the lack of the data. The new proposed permit will require the Permittee to collect hardness data for the 

five year permit cycle. This additional data will assist Ecology in calculating the water quality criteria 

and reasonable potential analysis for the future.

F. Whole Effluent Toxicity

Acute

WET testing conducted during effluent characterization showed no reasonable potential for effluent 

discharges to cause receiving water acute toxicity. The proposed permit does not impose an acute WET 

limit. TCG must retest the effluent before submitting an application for permit renewal. In addition: 

If this facility makes process or material changes which, in Ecology's opinion, increase the 

potential for effluent toxicity, then Ecology may (in a regulatory order, by permit modification, or 

in the permit renewal) require the facility to conduct additional effluent characterization. 

If WET testing conducted for submittal with a permit application fails to meet the performance 

standards in WAC 173-205-020, Ecology will assume that effluent toxicity has increased. TCG 

may demonstrate to Ecology that effluent toxicity has not increased, by performing additional 

WET testing after the process or material changes have been made.

Chronic
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WET testing conducted during effluent characterization showed no reasonable potential for effluent 

discharges to cause receiving water chronic toxicity. The proposed permit does not impose a chronic 

WET limit. TCG must retest the effluent before submitting an application for permit renewal. In addition:

If this facility makes process or material changes which, in Ecology's opinion, increase the 

potential for effluent toxicity, then Ecology may (in a regulatory order, by permit modification, or 

in the permit renewal) require the facility to conduct additional effluent characterization

If WET testing conducted for submittal with a permit application fails to meet the performance 

standards in WAC 173-205-020, Ecology will assume that effluent toxicity has increased. TCG 

may demonstrate to Ecology that effluent toxicity has not increased by performing additional 

WET testing after the process or material changes have been made.

G. Human Health

Washington’s water quality standards include 91 numeric human health-based criteria that Ecology must 

consider when writing NPDES permits. These criteria were established in 1992 by the U.S. EPA in its 

National Toxics Rule (40 CFR 131.36). The National Toxics Rule allows states to use mixing zones to 

evaluate whether discharges comply with human health criteria.

Ecology determined the effluent may contain chemicals of concern posing a risk to human health. 

Ecology determined this because data or process information indicates regulated chemicals occur in the 

discharge.

H. Sediment Quality

The aquatic sediment standards (WAC 173-204) protect aquatic biota and human health. Under these 

standards Ecology may require a facility to evaluate the potential for its discharge to cause a violation of 

sediment standards (WAC 173-204-400). You can obtain additional information about sediments at the 

Aquatic Lands Cleanup Unit website. http://www.ecy.wa.gov/programs/tcp/smu/sediment.html

Ecology could not determine at this time the potential for this discharge to cause a violation of sediment 

quality standards. If in the future Ecology determines a potential for violation of the Sediment Quality 

Standards, it will issue an order requiring TCG to demonstrate either:

The point of discharge is not an area of deposition or,

Toxics do not accumulate in the sediments even though the point of discharge is a depositional 

area.

I. Ground Water Quality Limits

The Ground Water Quality Standards, (chapter 173-200 WAC), protect beneficial uses of ground water. 

Permits issued by Ecology must not allow violations of those standards (WAC 173-200-100). 

TCG does not discharge wastewater to ground and therefore Ecology imposed no permit limits to protect 

ground water.

J. Comparison of Effluent Limits with Limits of the Previous Permit Issued on June 30, 2005

Table 9 Comparison of Effluent Limits
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Basis of 

Limit

Previous Effluent Limits:

Outfall # 001

Proposed Effluent Limits: 

Outfall # 001

Parameter Average Monthly Maximum Daily Average 

Monthly

Maximum 

Daily

Flow Technology 6.36 12.12 6.36 12.12

Total Suspended 

Solids, mg/L Technology 30 100 30 100

Oil and Grease, 

mg/L Technology 15 20 15 20

Chromium, mg/L Technology 0.20 0.20 0.20 0.20

Zinc, mg/L Technology 1.0 1.0 1.0 1.0

Temperature, oC

Water 

Quality

18° C when 

background is less 

than 18° C. 

Background plus 

0.3° C when 

background is 

greater than 18° C. 

no increase more 

than 28° C divided 

by background 

temperature plus 7.

18° C when 

background is 

less than 18° C. 

Background plus 

0.3° C when 

background is 

greater than 18° 

C. no increase 

more than 28° C 

divided by 

background 

temperature plus 

7.

16° C when 

background is 

less than 16° 

C. 

Background 

plus 0.3° C 

when 

background is 

greater than 

16° C. No 

increase more 

than 28° C 

divided by 

background 

temperature 

plus 7.

16° C when 

background 

is less than 

16° C. 

Background 

plus 0.3° C 

when 

background 

is greater 

than 16° C. 

No increase 

more than 

28° C 

divided by 

background 

temperature 

plus 7.

Oil and Grease, 

visual No visible sheen No visible sheen No visible sheen

No visible 

sheen

Dissolved 

Oxygen, mg/L

Water 

Quality Minimum, 8 mg/L N/A Minimum, 9.5 mg/L N/A

pH Technology 6.0 – 10.0 6.0 - 9.0

Total Residual

Chlorine , mg/L Technology 0.20 0.50 0.20 0.20
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Basis of 

Limit

Previous Effluent Limits:

Outfall # 001

Proposed Effluent Limits: 

Outfall # 001

Parameter Average Monthly Maximum Daily Average 

Monthly

Maximum 

Daily

Turbidity (NTU) Water 

Quality

5 NTU over 

background when 

background is less 

than 50 NTU. 

Maximum 10% 

increase over 

background when 

background is over 

50 NTU.

5 NTU over 

background 

when 

background is 

less than 50 

NTU. Maximum 

10% increase 

over background 

when 

background is 

over 50 NTU.

5 NTU over 

background 

when 

background is 

less than 50 

NTU. 

Maximum 

10% increase 

over 

background 

when 

background is 

over 50 NTU.

5 NTU over 

background 

when 

background 

is less than 

50 NTU. 

Maximum 

10% increase 

over 

background 

when 

background 

is over 50 

NTU.

Priority 

Pollutants less 

chromium and 

zinc, μg/L 

Technology Zero Zero

NonDetectable

amount

NonDetectable

amount

Basis of 

Limit

Previous Effluent Limits: 

Outfall # 002

Proposed Effluent Limits: 

Outfall # 002

Parameter Average Monthly Maximum Daily Average 

Monthly

Average 

weekly

Flow, MGD Technology 0.020 0.036 No Limit No Limit

Total Suspended 

Solids Technology 30 mg/L 45 mg/L 30 mg/L, 9 lbs/day

45 mg/L, 

13.5 lbs/day

BOD5, Technology 30 mg/L 45 mg/L 30 mg/L, 9 

lbs/day

45 mg/L, 

13.5 lbs/day

Parameter Average Monthly Maximum Daily Average 

Monthly

Maximum 

Daily

Fecal Coliform 

#/100ml Technology 200 400 200 400

Total Residual

Chlorine , mg/L Technology 2.0 2.0 2.0 2.0

IV MONITORING REQUIREMENTS

Ecology requires monitoring, recording, and reporting (WAC 173-220-210 and 40 CFR 122.41) to verify 

that the treatment process is functioning correctly and that the discharge complies with the permit’s 

effluent limits.

The monitoring schedule is detailed in the proposed permit under Condition S.2. 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.
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A. Lab Accreditation

Ecology requires that facilities must use a laboratory registered or accredited under the provisions of 

chapter 173-50 WAC, Accreditation of Environmental Laboratories to prepare all monitoring data (with 

the exception of certain parameters).

V OTHER PERMIT CONDITIONS

A. Reporting and Recordkeeping

Ecology based permit condition S3. on our authority to specify any appropriate reporting and 

recordkeeping requirements to prevent and control waste discharges (WAC 173-220-210).

B. Non Routine and Unanticipated Discharges

Occasionally, this facility may generate wastewater which was not characterized in the permit application 

because it is not a routine discharge and was not anticipated at the time of application. These wastes 

typically consist of waters used to pressure-test storage tanks or fire water systems or of leaks from 

drinking water systems. 

The permit authorizes non-routine and unanticipated discharges under certain conditions. The facility 

must characterize these waste waters for pollutants and examine the opportunities for reuse. Depending 

on the nature and extent of pollutants in this wastewater and on any opportunities for reuse, Ecology may:

Authorize the facility to discharge the wastewater.

Require the facility to treat the wastewater.

Require the facility to reuse the wastewater.

C. Spill Plan

This facility stores a quantity of chemicals on-site that have the potential to cause water pollution if 

accidentally released. Ecology can require a facility to develop best management plans to prevent this 

accidental release [section 402(a)(1) of the Federal Water Pollution Control Act (FWPCA) and RCW 

90.48.080]. 

TCG developed a plan for preventing the accidental release of pollutants to state waters and for 

minimizing damages if such a spill occurs. The proposed permit requires the facility to update this plan 

and submit it to Ecology.

D. Solid Waste Control Plan

TCG could cause pollution of the waters of the state through inappropriate disposal of solid waste or 

through the release of leachate from solid waste. This proposed permit requires this facility to update the 

approved solid waste control plan designed to prevent solid waste from causing pollution of waters of the 

state. The updated plan must be submitted to Ecology for approval (RCW 90.48.080).

E. Treatment System Operating Plan
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Ecology requires industries to take all reasonable steps to properly operate and maintain their wastewater 

treatment system in accordance with state and federal regulations (40 CFR 122.41(e) and WAC 173-220-

150 (1)(g)). The facility has prepared and submitted an operation and maintenance manual as required by 

state regulation for the construction of wastewater treatment facilities (WAC 173-240-150). 

Implementation of the procedures in the Treatment System Operating Plan ensures the facility’s 

compliance with the terms and limits in the permit.

F. General Conditions

Ecology bases the standardized General Conditions on state and federal law and regulations. They are 

included in all individual industrial NPDES permits issued by Ecology.

VI. PERMIT ISSUANCE PROCEDURES

A. Permit Modifications

Ecology may modify this permit for any of the reasons specified in state or federal regulations. Ecology

may modify this permit to impose numerical limits, if necessary to comply with water quality standards

for surface waters, with sediment quality standards, or with water quality standards for ground waters, 

after obtaining new information from sources such as inspections, effluent monitoring, outfall studies, and 

effluent mixing studies. Ecology may also modify this permit to comply with new or amended state or 

federal regulations.

B. Proposed Permit Issuance

This proposed permit includes all statutory requirements for Ecology to authorize a wastewater discharge. 

The permit includes limits and conditions to protect human health and aquatic life, and the beneficial uses 

of waters of the state of Washington. Ecology proposes to issue this permit for a term of five years.
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VII. REFERENCES FOR TEXT AND APPENDICES

Environmental Protection Agency (EPA) 

1991. Technical Support Document for Water Quality-based Toxics Control. EPA/505/2-90-001.

1988. Technical Guidance on Supplementary Stream Design Conditions for Steady State Modeling. 

USEPA Office of Water, Washington, D.C.

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. 

1972. Characterization of Stream Reaeration Capacity. EPA-R3-72-012. (Cited in EPA 1985 op.cit.) 

Washington State Department of Ecology.

1994. Permit Writer’s Manual. Publication Number 92-109 

Washington State Department of Ecology. 

2007. Focus Sheet on Solid Waste Control Plan, Developing a Solid Waste Control Plan for Industrial 

Wastewater Discharge Permittees. Publication Number 07-10-024

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.

1979. In-stream Deoxygenation Rate Prediction. Journal Environmental Engineering Division, ASCE. 

105(EE2). (Cited in EPA 1985 op.cit.) 
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APPENDIX A--PUBLIC INVOLVEMENT INFORMATION

Ecology proposes to reissue a permit to (insert the facility name). The permit prescribes operating 

conditions and wastewater discharge limits. This fact sheet describes the facility and Ecology’s reasons 

for requiring permit conditions. 

Ecology placed a Public Notice of Application on June 4,2009, and June 11, 2009, in the Daily Chronicle 

to inform the public about the submitted application and to invite comment on the reissuance of this 

permit. 

Ecology will place a Public Notice on June 9, 2010, in the Daily Chronicle to inform the public and to 

invite comment on the proposed reissuance of this National Pollutant Discharge Elimination System 

permit as drafted.

The Notice –

Tells where copies of the draft Permit and Fact Sheet are available for public evaluation (a local 

public library, the closest Regional or Field Office, posted on our website.).

Offers to provide the documents in an alternate format to accommodate special needs.

Asks people to tell us how well the proposed permit would protect the receiving water.

Invites people to suggest fairer conditions, limits, and requirements for the permit.

Invites comments on Ecology’s determination of compliance with antidegradation rules.

Urges people to submit their comments, in writing, before the end of the comment period

Tells how to request a public hearing about the proposed NPDES Permit.

Explains the next step(s) in the permitting process.

Ecology has published a document entitled Frequently Asked Questions about Effective Public 

Commenting which is available on our website at http://www.ecy.wa.gov/biblio/0307023.html. 

You may obtain further information from Ecology by telephone, 360-407-6280, or by writing to the 

permit writer at the address listed below.

Water Quality Permit Coordinator

Department of Ecology

Southwest Regional Office

P.O. Box 47775

Olympia, WA 98504-7775
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APPENDIX B--GLOSSARY

1-DMax or 1-day maximum temperature--The highest water temperature reached on any given day. 

This measure can be obtained using calibrated maximum/minimum thermometers or continuous 

monitoring probes having sampling intervals of thirty minutes or less. 

7-DADMax or 7-day average of the daily maximum temperatures--The arithmetic average of seven 

consecutive measures of daily maximum temperatures. The 7-DADMax for any individual day is 

calculated by averaging that day's daily maximum temperature with the daily maximum temperatures

of the three days prior and the three days after that date.

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--The acronym for “all known, available, and reasonable methods of prevention, control and 

treatment.” AKART is a technology-based approach to limiting pollutants from wastewater 

discharges which requires an engineering judgment and an economic judgment. AKART must be 

applied to all wastes and contaminants prior to entry into waters of the state in accordance with RCW 

90.48.010 and 520, WAC 173-200-030(2)(c)(ii), and WAC 173-216-110(1)(a).

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.

Annual Average Design Flow (AADF)--The average of the daily flow volumes anticipated to occur over 

a calendar year.

Average Monthly Discharge Limit--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 receiving waters 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.
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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.

Compliance Inspection - With 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. In 

addition it includes 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. Ecology may conduct additional 

sampling.

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.

Detection Limit--See Method Detection Level.

Dilution Factor (DF)--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 percent by volume and the receiving water 90

percent.

Engineering Report--A document which thoroughly examines the engineering and administrative 

aspects of a particular domestic or industrial wastewater facility. The report must 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 a period of time 

as is feasible.

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.
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Maximum Daily Discharge Limit--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. 

Maximum Day Design Flow (MDDF)--The largest volume of flow anticipated to occur during a one-day 

period, expressed as a daily average.

Maximum Month Design Flow (MMDF)--The largest volume of flow anticipated to occur during a 

continuous 30-day period, expressed as a daily average.

Maximum Week Design Flow (MWDF)--The largest volume of flow anticipated to occur during a 

continuous 7-day period, expressed as a daily average.

Method Detection Level (MDL)--The minimum concentration of a substance that can be measured and 

reported with 99 percent confidence that the pollutant concentration is above zero and is determined 

from analysis of a sample in a given matrix containing the pollutant.

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. It is the negative logarithm of the hydrogen ion 

concentration. A pH of 7.0 is defined as neutral, and large variations above or below this value are 

considered harmful to most aquatic life.

Peak Hour Design Flow (PHDF)--The largest volume of flow anticipated to occur during a one-hour 

period, expressed as a daily or hourly average.

Peak Instantaneous Design Flow (PIDF)--The maximum anticipated instantaneous flow.

Quantitation Level (QL)--The smallest detectable concentration of analyte greater than the Detection 

Limit (DL) where the accuracy (precision &bias) achieves the objectives of the intended purpose.

This may also be called Minimum Level or Reporting Level.

Reasonable Potential--A reasonable potential to cause a water quality violation, or loss of sensitive 

and/or important habitat.

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 decisionmaking 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).

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 receiving waters may result in solids accumulation. Apart from any 
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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. 

Solid waste--All putrescible and non-putrescible solid and semisolid wastes including, but not limited to, 

garbage, rubbish, ashes, industrial wastes, swill, sewage sludge, demolition and construction wastes, 

abandoned vehicles or parts thereof, contaminated soils and contaminated dredged material, and 

recyclable materials.

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 limits because of factors beyond the reasonable control of the 

facility. 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 receiving waters.
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APPENDIX C-COMPLIANCE HISTORY AND-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 Ecology’s homepage at:

http://www.ecy.wa.gov/programs/eap/pwspread/pwspread.html.
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Table 2- Priority Pollutant Laboratory Report Submitted on April 13, 2010

Matrix Date 

Sampled

Date 

Received

Date 

Analyzed

Method Compound Result Qualifiers Units MDL PQL

Water 11/20/2008 11/20/2008 11/20/2008 EPA 150.1 pH 8.02 pH Units NA NA

Water 11/20/2008 11/20/2008 12/1/2008 EPA 1664-A Oil and Grease 2 U mg/L 1.84 2

Water 11/20/2008 11/20/2008 11/26/2008 EPA 200.7 Boron 2000 μg/L 40 150

Water 11/20/2008 11/20/2008 11/26/2008 EPA 200.7 Tin 50 U μg/L 32 50

Water 11/20/2008 11/20/2008 11/26/2008 EPA 200.7 Titanium 10 U μg/L 4.9 10

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Aluminum 210 μg/L 0.17 0.82

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Antimony 2 μg/L 0.07 0.21

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Arsenic 5 μg/L 0.08 0.24

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Barium 180 μg/L 0.05 0.15

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Beryllium 0.15 U μg/L 0.05 0.15

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Cadmium 0.18 U μg/L 0.06 0.18

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Chromium 7 μg/L 0.07 0.2

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Cobalt 0.13 μg/L 0.04 0.11

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Copper 2 μg/L 0.06 0.18

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Iron 1 U μg/L 5.6 28

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Lead 0.22 μg/L 0.06 0.17

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Magnesium 19000 μg/L 5.9 29

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Manganese 54 μg/L 0.05 0.15

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Molybdenum 21 μg/L 0.66 0.29

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Nickel 1 μg/L 0.05 0.14

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Selenium 3 μg/L 0.13 0.39

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Silver 0.22 U μg/L 0.08 0.22

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Thallium 0.28 U μg/L 0.06 0.28

Water 11/20/2008 11/20/2008 11/21/2008 EPA 200.8 Zinc 1 μg/L 0.11 0.33

Water 11/20/2008 11/20/2008 11/25/2008 EPA 350.3 Ammonia 0.2 U mg/L-N 0.08 0.20

Water 11/20/2008 11/20/2008 12/3/2008 EPA 375.4 Sulfate 440 mg/L 0.98 5.0

Water 11/20/2008 11/20/2008 11/24/2008 EPA 420.1 Total 

Phenolics

0.01 U mg/L 0.006 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 4,4'-DDD 0.01 U μg/L 8E-04 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 4,4'-DDE 0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 4,4'-DDT 0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Aldrin 0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 alpha-BHC 0.01 U μg/L 0.001 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 AlphaChlordane0.01 U ug/L 0.001 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 beta-BHC 0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 12/1/2008 EPA 608 Decachlorobip

henyl

110 % N/A N/A
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Matrix Date 

Sampled

Date 

Received

Date 

Analyzed

Method Compound Result Qualifiers Units MDL PQL

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 delta-BHC 0.01 U μg/L 8E-04 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Dieldrin 0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Endosulfan I 0.01 U μg/L 0.001 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Endosulfan II 0.01 U μg/L 9E-04 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Endosulfan 

Sulfate

0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Endrin 0.01 U μg/L 0.001 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Endrin 

Aldehyde

0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Endrin Ketone 0.01 U μg/L 0.008 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 gamma-BHC 

(Lindane)

0.01 U μg/L 0.001 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 gamaChlordane0.01 U μg/L 0.001 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Heptachlor 0.01 U μg/L 0.007 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Heptachlor 

Epoxide

0.01 U μg/L 0.002 0.01

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Methoxychlor 0.01 U μg/L 0.006 0.01

Water 11/20/2008 11/20/2008 12/1/2008 EPA 608 PCB 0.1 U μg/L 0.012 0.1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 TetrachloroM-Xylene99 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 608 Toxaphene 1 U μg/L 0.11 1.0

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,1,1-

Trichloroethan

e

1 U μg/L 0.26 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,1,2,2-

Tetrachloroeth

ane

1 U μg/L 0.15 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,1,2-

Trichloroethan

e

1 U μg/L 0.19 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,1-

Dichloroethane

1 U μg/L 0.20 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,1-

Dichloroethyle

ne

1 U μg/L 0.39 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,2-

Dichloroethane

1 U μg/L 0.15 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,2-

Dichloroethane

-d4

104 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 1,2-

Dichloropropa

ne

1 U μg/L 0.31 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 2-

Chloroethylvin

yl Ether

10 U μg/L 0.72 10

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 4-

Bromofluorobe

nzene

110 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Acrolein 10 U μg/L 5.92 10

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Acrylonitrile 10 U μg/L 0.65 10

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Benzene 1 U μg/L 0.32 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Bischloromethylether1 U μg/L 0.72 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Bromoform 1 U μg/L 0.16 1
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Matrix Date 

Sampled

Date 

Received

Date 

Analyzed

Method Compound Result Qualifiers Units MDL PQL

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Carbon 

Tetrachloride

1 U μg/L 0.08 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Chlorobenzene 1 U μg/L 0.17 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Chlorodibromo

methane

1 U μg/L 0.17 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Chloroethane 1 U μg/L 0.5 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Chloroform 1 U μg/L 0.11 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 cis-1,3-

Dichloroprope

ne

1 U μg/L 0.24 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Dibromofluoro

methane

85 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Dichlorobromo

methane

1 U μg/L 0.20 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Dichlorodifluo

romethane

1 U μg/L 0.20 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Ethylbenzene 1 U μg/L 0.20 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Methyl

Bromide

1 U μg/L 0.29 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Methyl 

Chloride

1 U μg/L 0.29 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Methylene 

chloride

1 U μg/L 1.32 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Tetrachloroeth

ylene

1 U μg/L 0.38 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Toluene 1 U μg/L 0.26 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Toluene-d8 116 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 trans-1,2-

Dichloroethyle

ne

1 U μg/L 0.28 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 trans-1,3-

Dichloroprope

ne

1 U μg/L 0.15 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Trichloroethyl

ene

1 U μg/L 0.22 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Trichlorofluor

omethane

1 U μg/L 0.16 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 624 Vinyl chloride 1 U μg/L 0.11 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 1,2,4-

Trichlorobenze

ne

2.5 U μg/L 0.27 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 1,2-

Dichlorobenze

ne

2.5 U μg/L 0.19 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 1,3-

Dichlorobenze

ne

2.5 U μg/L 0.18 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 1,4-

Dichlorobenze

ne

2.5 U μg/L 0.24 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2,4,6-

Tribromophen

ol

112 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2,4,6-

Trichlorophen

ol

2.5 U μg/L 0.32 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2,4-

Dichloropheno

l

2.5 U μg/L 0.41 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2,4-

Dimethylphen

ol

2.5 U μg/L 0.43 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2,4-

Dinitrophenol

10 U μg/L 0.69 10
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Matrix Date 

Sampled

Date 

Received

Date 

Analyzed

Method Compound Result Qualifiers Units MDL PQL

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2,4-

Dinitrotoluene

2.5 U μg/L 0.35 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2,6-

Dinitrotoluene

2.5 U μg/L 0.37 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2-

Chloronaphtha

lene

2.5 U μg/L 0.14 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2-

Chlorophenol

2.5 U μg/L 0.26 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2-

Fluorobiphenyl

71 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2-

Fluorophenol

79 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 2-Nitrophenol 2.5 U μg/L 0.38 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 3,3-

Dichlorobenzi

dine

20 U μg/L 11.2 20

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 3,4-

Benzofluorant

hene

1 U μg/L 1.00 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 4,6-Dinitro-oCresol10 U μg/L 0.66 10

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 4-

Bromophenylphenylether

2.5 U μg/L 0.25 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 4-

Chlorophenylphenylether

2.5 U μg/L 0.29 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 4-Nitrophenol 2.5 U μg/L 0.9 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Acenaphthene 1 U μg/L 0.21 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Acenaphthylen

e

1 U μg/L 0.25 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Anthracene 1 U μg/L 0.21 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Azobenzene 2.5 U μg/L 0.24 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Benzidine 20 U μg/L 0.38 20

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Benzo(a)Anthr

acene

1 U μg/L 0.15 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Benzo(a)Pyren

e

1 U μg/L 0.53 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Benzo(ghi)Per

ylene

1 U μg/L 0.49 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Benzo(k)Fluor

anthene

1 U μg/L 0.76 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 bis(2-

Chloroethoxy)

Methane

2.5 U μg/L 0.24 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Bis(2-

Chloroethyl)Et

her

2.5 U μg/L 0.21 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 bis(2-

chloroisopropy

l)Ether

2.5 U μg/L 0.23 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 bis(2-

Ethylhexyl)Pht

halate

2.5 U μg/L 0.33 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Butylbenzyl 

phthalate

2.5 U μg/L 0.50 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Chrysene 1 U μg/L 0.24 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Dibenz(a,h)An

thracene

1 U μg/L 0.56 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Diethylphthala

te

2.5 U μg/L 0.19 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Dimethyl 

Phthalate

2.5 U μg/L 0.19 2.5
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 41 of 70

Matrix Date 

Sampled

Date 

Received

Date 

Analyzed

Method Compound Result Qualifiers Units MDL PQL

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Di-nButylphthalate2.5 U μg/L 0.22 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Di-n-Octyl 

Phthalate

2.5 U μg/L 1.12 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Fluoranthene 1 U μg/L 0.46 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Fluorene 1 U μg/L 0.33 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Hexachloroben

zene

2.5 U μg/L 0.13 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Hexachlorobut

adiene

2.5 U μg/L 0.24 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Hexachlorocyc

lopentadiene

2.5 U μg/L 0.77 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Hexachloroeth

ane

2.5 U μg/L 0.27 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Indeno(1,2,3-

cd)Pyrene

1 U μg/L 0.56 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Isophorone 2.5 U μg/L 0.25 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Naphthalene 1 U μg/L 0.12 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Nitrobenzene 2.5 U μg/L 0.28 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Nitrobenzened573 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Nnitrosodimethy

lamine

2.5 U μg/L 0.83 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 N-Nitroso-Din-Propylamine2.5 U μg/L 0.30 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 NNitrosodiphen

ylamine

2.5 U μg/L 1.60 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 P-Chloro-mCresol2.5 U μg/L 0.43 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Pentachloroph

enol

10 U μg/L 0.28 10

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Phenanthrene 1 U μg/L 0.22 1

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Phenol 2.5 U μg/L 0.28 2.5

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Phenol-d6 80 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 p-Terphenyld1494 % N/A N/A

Water 11/20/2008 11/20/2008 11/26/2008 EPA 625 Pyrene 1 U μg/L 0.29 1

Water 11/20/2008 11/20/2008 12/2/2008 SM 2120B Color 43 Color 

Units

5.8 15

Water 11/20/2008 11/20/2008 11/25/2008 SM 2540-D Total 

Suspended 

Solids

4 mg/L 0.49 0.50

Water 11/20/2008 11/20/2008 11/25/2008 SM 4500-F C Fluoride 2.1 mg/L 0.025 0.20

Water 11/20/2008 11/20/2008 11/26/2008 SM 5210 B BOD 5.2 mg/L N/A 2.0

Water 11/20/2008 11/20/2008 11/26/2008 SM 5220-D COD 2 U mg/L 0.31 2.0

Water 11/20/2008 11/20/2008 11/21/2008 SM 9222D Fecal Coliform 

by MF

40 CFU/100

ml

N/A 1

Water 11/20/2008 11/20/2008 11/20/2008 SM4500-ClGTotal Residual 

Chlorine

0.04 mg/L 0.017 0.04

Water 11/20/2008 11/20/2008 11/21/2008 SM4500CNETotal Cyanide 0.01 U mg/L 0.004 0.01

Water 11/20/2008 11/20/2008 11/21/2008 SM4500NO2

B

Nitrite 0.04 mg/L-N 0.004 0.01

Water 11/20/2008 11/20/2008 11/25/2008 SM4500NO3

E

Nitrate 4.8 mg/L-N 0.24 0.5

Water 11/20/2008 11/20/2008 11/26/2008 SM4500-P E Total 

Phosphorus

0.2 mg/L 0.066 0.2
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 42 of 70

Matrix Date 

Sampled

Date 

Received

Date 

Analyzed

Method Compound Result Qualifiers Units MDL PQL

Water 11/20/2008 11/20/2008 12/2/2008 SM4500-S2-

E

Sulfide 0.5 U mg/L 0.18 0.5

Water 11/20/2008 11/20/2008 12/3/2008 SM4500-

SO3-B

Sulfite 2 U mg/L 1.2 2.0

Water 11/20/2008 11/20/2008 12/4/2008 SM5310 B Total Organic 

Carbon

6 mg/L 0.60 2.5

Water 11/20/2008 11/20/2008 11/24/2008 SM5540 C Surfactants 

(MBAS)

0.04 mg/L 0.026 0.03

Water 11/20/2008 11/20/2008 12/3/2008 Summation Total Organic 

Nitrogen as N

0.5 U mg/L-N 0.24 0.5

Water 11/20/2008 11/20/2008 11/21/2008 SW846 3010 Digestion d N/A N/A

Water 11/20/2008 11/20/2008 11/25/2008 EPA 350.3 Ammonia 3.4 mg/L-N 0.08 0.2

Water 11/20/2008 11/20/2008 11/26/2008 SM 5210 B BOD 3.3 mg/L N/A 2.0

Water 11/20/2008 11/20/2008 11/26/2008 SM 5220-D COD 2 U mg/L 0.31 2.0

Water 11/20/2008 11/20/2008 12/4/2008 SM5310 B Total Organic 

Carbon

5 mg/L 0.60 2.5

Table 3- Reasonable Potential to exceed the water quality standards

State Water 

Quality Standard 

Max concentration at 

edge of ... 

Metal 

Criteria 

Translator 

as decimal 

Metal 

Criteria 

Translator 

as decimal 

Ambient 

Conc. 

(metals as 

dissolved) 

Acute Chroni

c 

Acute 

Mixing 

Zone 

Chronic 

Mixing 

Zone 

LIMIT 

REQ’D

Parameter Acute Chronic μg/L μg/L μg/L μg/L μg/L

Total Residual

Chlorine 0 19 11 1149.88 1149.88 YES

Arsenic 1 1 0 360 190 30.99 30.99 NO

Chromium 0.99 0.99 0 15 10 16.11 16.11 YES

Selenium 1 1 0 20 5 185.96 185.96 YES

Table 3- Reasonable Potential to exceed the water quality standards -continued

Effluent 

percentile 

value 

Max 

effluent 

conc. 

measured 

Coeff of 

Variation 

# of 

samples 

Multiplier Acute 

Dil’n 

Factor 

Chronic 

Dil’n 

Factor

Parameter Pn μg/L CV s n 1 1

Total 

Residual

Chlorine 

0.95 0.911 870 1.17 0.93 32 1.32 1 1

Arsenic 0.95 0.05 5 0.6 0.55 1 6.2 1 1

Chromium 0.95 0.05 7 0.6 0.55 5 2.32 1 1

Selenium 0.95 0.05 80 0.6 0.55 1 2.32 1 1

Table 4 – Reasonable Potential Analysis based on EPA recommended water quality criteria (Memo 

June 7, 2010)
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

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Parameter

State Water Quality 

Standard

Max 

concentration 

at edge of...

Metal 

Criteria 

Translator 

as 

decimal

Metal 

Criteria 

Translator 

as 

decimal

Ambient 

Concentration 

(metals as 

dissolved) Acute Chronic

Acute 

Mixing 

Zone

Chronic 

Mixing 

Zone

LIMIT 

REQ'D?

Effluent 

percentile 

value

Max effluent 

conc. 

measured 

(metals as 

total 

recoverable)

Coeff 

Variation

# of 

samples Multiplier

Acute 

Dil'n 

Factor

Chronic 

Dil'n 

Factor

Acute Chronic ug/L ug/L ug/L ug/L ug/L Pn ug/L CV s n

Copper 0.83 0.83 13.0000 9.0000 10.29 10.29 YES 0.95 0.050 2.00 0.60 0.55 1 6.20 1 1

Lead 0.95 0.95 65.0000 2.5000 1.30 1.30 NO 0.95 0.050 0.22 0.60 0.55 1 6.20 1 1

Nickel 0.99 0.99 470.0000 52.0000 6.14 6.14 NO 0.95 0.050 1.00 0.60 0.55 1 6.20 1 1

Zinc 0.95 0.95 120.0000 120.0000 5.86 5.86 NO 0.95 0.050 1.00 0.60 0.55 1 6.20 1 1
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

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FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

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APPENDIX D--RESPONSE TO COMMENTS

Earthjustice submitted comments on July 9, 2010

Comment 1

Waste Streams

The proposed Permit and Fact Sheet disclose that several waste streams make up TransAlta’s wastewater 

discharge covered by this Permit. See pages 6-10 Fact Sheet. Included in those waste streams is 

circulating water cooling tower blowdown, units 1 and 2 boiler drains, cooling tower basin drains, bottom 

ash system surge tank overflows, coal pile runoff, and flue gas desulfurization (FGD) wastewater. It 

appears that TransAlta, for the industrial (as opposed to sanitary effluent) wastewater uses settling ponds. 

Some flocculation is used, but it is unclear from the Fact Sheet to which wastes, exactly, the chemical 

treatment is applied. It appears to be only to the coal pile runoff. There is no apparent case-by-case 

analysis of BAT demonstrated in the Permit, Fact Sheet, or file for this Permit. The Fact Sheet discloses 

application of the old, existing BAT effluent limitation guidelines for cooling tower blowdown only. Fact 

Sheet, pp. 15-16. It also appears that Ecology has not assessed/applied AKART for the industrial process 

wastewater.

Ecology Response

TransAlta Centralia Generation (TCG), Figure 3, flow treatment schematic on page 8 of the fact sheet 

shows that wastewater chemical treatment occurs at the coal pile runoff collection pond. In addition, the 

WFGD-scrubber wastewater is treated before it reaches to the coal pile runoff treatment pond. The fact 

sheet has addressed EPA’s guidelines for the cooling tower blowdown industrial process (please see page 

15 & 16 of the TCG fact sheet). The other industrial process wastewaters have been determined by 

Ecology to be all known available reasonable treatment methods (AKART) through approval of 

engineering or use of effluent guidelines. For example, the wet flue gas desulfurization (WFGD)

scrubber wastewater used AKART when TCG treated the wastewater before discharging to the coal pile 

runoff treatment unit. Figures 1 and 2 show a treatment train for WFGD generated at the TCG operation. 

Ecology reviewed and approved this WFGD treatment engineering report on December 16, 2005.

Ecology has used the best available technology (BAT) guidelines for the cooling tower blowdown as the 

final effluent monitoring as the interim standard for all industrial process waste streams at the TCG site. 

Even though the permit does not directly specify individual limits on every waste stream that does not 

mean those streams are not subject to the same limits as those applied to the cooling tower blowdown 

wastewater. The cooling tower blowdown pollutant limits are the most stringent limits except for 

chromium, zinc and chlorine as federal law requires.

TCG’s WFGD scrubber wastewater treatment is nearly identical to EPA’s proposed guidance for WFGD 

scrubber wastewater treatment in their study of October 2009 (Figure 3). In addressing the coal 

combustion residue solid waste (bottom and fly ash), Ecology has issued a separate NPDES permit for 

this industrial process in 2009. The proposed compliance schedule requires the Permittee to produce an 

AKART analysis which will lead to potential AKART limits (Please see response to comment 7C). 

Action Taken: Added documentation confirming the WFGD blowdown is treated.
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

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FACT SHEET FOR NPDES PERMIT WA 0001546

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FACT SHEET FOR NPDES PERMIT WA 0001546

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FACT SHEET FOR NPDES PERMIT WA 0001546

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Comment 2

Waterbodies Affected

TransAlta discharges these wastes to Hanaford Creek at Outfall 001. The discharge is approximately 1⁄2 to 

3⁄4 mile from the confluence of Hanaford Creek and the Skookumchuck River. The Skookumchuck is a 

tributary of the Chehalis River. According to the Washington Department of Fish and Wildlife’s website, 

Hanaford Creek has a winter steelhead run and the Skookumchuck has fall Chinook and chum salmon 

runs.

A sibling company, TransAlta Centralia Mining, L.L.C. is the permittee on two other NPDES permits 

related to the facility in Centralia, Washington. Permit No. 0040215 covers discharges from a new 

landfill TransAlta has created in an existing coal mine pit. The landfill appears to accept fly and bottom

ash from the coal-plant steam generation operation. In its first year, the landfill has had problems 

complying with its NPDES Permit requirements. Permit No. 0037338 covers non-continuous discharges 

from a series of other existing mine pits on the larger facility site. The mine pit permit is linked to the 

Permit under review here in that industrial process wastewater and coal pile runoff which is covered 

under this Permit, is routed to the Pond 3E mine-pit system of ponds during summer low-flow months, 

and ultimately discharged under Permit 0037338. Fact Sheet at p. 11. It appears that there is no treatment 

other than settling for the pollutants that go this route. All three permits discharge within the 

Skookumchuck watershed, some to Hanaford Creek, some to other creeks that join the Skookumchuck.

The Conservation Organizations are concerned with separation of the subject Permit and Permit 0037338 

when the same pollutants and sources of pollutants are discharged under each. They should be treated as

one NPDES permit with multiple outfalls. Also, routing cooling tower blowdown and FGD wastewater 

to mine pits where acidic conditions are likely present, contributes to the dissolution of metals in the 

blowdown and FGD waste streams which in turn contributes to higher discharges of dissolved metals 

under the mine pit Permit. It is clear that Permit 0037338 does not impose BAT and is also not in 

compliance with the CWA. By treating them separately, TransAlta and the state deprive the public of the 

opportunity to understand and comment on the entirety of the system and the cumulative damage to the 

environment. Ecology should consolidate these permits and reissue them as one with full public process.

Ecology’s Response

Ecology’s Water Quality Program has issued TransAlta Centralia Operation three separate NPDES 

permits for different industrial processes so Ecology could accurately monitor the wastewater of each 

industrial process and set the appropriate limits for each process. It is important that Ecology regulate and 

monitor these wastes streams/pollutants at the source. Each permit that Ecology has issued to TransAlta 

(TransAlta Centralia Mining, TransAlta Centralia Generation LLC and Limited Purpose Landfill) has 

different applicable federal regulations. Each type of permit has different limits based on the 

concentrations of the pollutants allowed by federal and state law for surface water. This practice by 

Ecology to require each creek and tributary which is receiving treated wastewater to meet the federal and 

state water quality standards is a stricter standard for TransAlta to meet than just monitoring the overall 

water quality at downstream Hanaford Creek and Skookumchuck River. Each permit is significantly 

complex and an attempt to combine them would not result in an improved and understandable permit. 

Also, when TCG discharges to pond 3E, the Permittee is required to comply with all applicable permit 

effluent limits, except temperature and dissolved oxygen. Currently, pond 3E is not state designated 

surface water, therefore temperature and dissolved oxygen limits are not applied. 

Action Taken: None
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

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Comment 3

Pollutants

There are a variety of pollutants in TransAlta’s discharge to Outfall 001 of this Permit as well as 

temperature limitations. Some of them are conventional pollutants and, consistent with EPA’s Final 

Study, many of the pollutants are priority pollutants of concern such as mercury, selenium, copper, 

chromium, lead, and arsenic. The Fact Sheet also identifies sulfates. TransAlta has recorded violations of 

Permit conditions for BOD, TSS, and chlorine during the previous 5 years. Correspondence in the file 

appears to indicate that TransAlta blames these violations, for the most part, on algae growth in its pond 

system. While that may be the cause, it does not excuse the violations. There is no discussion in the Fact 

Sheet or file of how these violations will be avoided in the future (one of the BOD violations was June of 

2009). 

It also appears from correspondence between TransAlta and Ecology in the spring of 2010 that TransAlta 

has improperly measured temperature 600 feet downstream of outfall 001 in violation of the permit 

requirements to sample for temperature 300 feet from the outfall. Therefore, it appears that on some 

occasions, TransAlta has also violated the permit temperature limits.

Ecology’s Response

Whenever any permit violation occurs, the Permittee is issued a warning letter and this requires the 

Permittee to investigate and resolve the problem. During the five year permit cycle, Ecology issued 23

warning letters to TCG. These warning letters occurred infrequently and Trans Alta was able to correct 

the problem within a short time frame. These problems have not persisted, so further action by Ecology 

was not needed. 

There was correspondence between Ecology and Trans Alta pertaining to the distance downstream that 

TCG was monitoring the temperature for outfall 001. This correspondence is not pertinent to the 

requirements in this permit. The 2005 TCG NPDES permit only requires Trans Alta to monitor the 

background temperature of upstream from the outfall 001 on Hanaford Creek. TCG has been doing their 

own downstream monitoring of temperature which is not part of the permit requirements. 

Action Taken: None

Comment 4

Antidegradation

The Fact Sheet outlines Washington antidegradation requirements, but simply states, with no explanation 

or supporting information, that the TransAlta coal plant must meet Tier I levels of antidegradation. This 

suggests the most minimal level of antidegradation protection. It is unclear from the Fact Sheet whether 

this applies to Hanaford Creek only or also to the Skookumchuck and other downstream waters. 

Downstream is relevant because many of the pollutants of concern are conservative (e.g. nutrients) and/or 

bioaccumulative meaning that they are not necessarily more dilute or less damaging the further 

downstream they travel. Moreover, because there is no discussion or supporting information regarding 

the antidegradation consideration for this Permit, it is impossible to discern whether the antidegradation 

analysis was properly made pollutant by pollutant. A waterbody may be Tier I for some pollutants, but 

Tier II for others, requiring a higher level of protection.

Ecology’s Response
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 51 of 70

Tier I criteria ensures that existing and designated uses are maintained and protected and it applies to all 

waters and all sources of pollutants. By default, TCG facility is to meet the Tier I criteria. Tier II criteria 

applies only to a new or expanded facility causing a measureable increase of pollutant in the receiving 

water. TCG is not a new or expanded facility.

The receiving water body of outfall 001 is Hanaford Creek and the limits apply to the wastewater 

discharge to Hanaford Creek.

Action Taken: None

Comment 5

Mixing Zone

It is unclear whether the Permit includes a mixing zone in Hanaford Creek for Outfall 001. The Fact 

Sheet describes in detail Washington’s regulations regarding mixing zones and how they are calculated, 

but it contains no information specific to this Permit and simply concludes with the following statement: 

“The water quality standards impose certain conditions before allowing the discharger a mixing zone.” 

Fact Sheet at p. 20. It appears that the previous version of the Permit included requirements for a mixing 

zone study. Later in the Fact Sheet, in the section describing temperature requirements in Washington, 

there is a statement that “[t]he threshold criteria apply at the edge of the chronic mixing zone.” Fact Sheet 

at p. 22. It is unclear whether this reference is to a mixing zone to be included in the Permit or if it is a 

general reference regarding general Washington requirements. Correspondence from TransAlta in May 

of 2010 suggests that TransAlta expects a mixing zone for pH. Finally, there is no disclosure of a mixing 

zone in the Permit itself. Reading the Fact Sheet and the Permit as a whole, the Conservation 

Organizations understand that this Permit does not allow a mixing zone. If this is incorrect, please clarify 

the requirements and see mixing zone comments below.

Ecology Response

The current permit does not authorize mixing zone to meet the technology based effluent limits. In the 

current permit, Ecology has corrected the permit limit for pH. TCG is required to meet the technology 

based limits for pH 6.0 to 9.0, and these changes are reflected in the new proposed permit. 

Action Taken: Changed pH maximum limit from 10.0 to 9.0 to comply with the federal law 

requirements

Comment 6

WQBELs

The Fact Sheet discloses that for chromium and chlorine, AKART is less stringent than the Water Quality 

standards and that for the previous five years of the permit, Water Quality Based Effluent Limits 

(“WQBELs”) would have been exceeded for these two pollutants. Fact Sheet at p. 21. More clearly 

stated, for the last 5+ years, TransAlta’s discharge has been causing and/or contributing to violations of 

water quality standards for chlorine and chromium. It should be noted that even the lenient chlorine limit 

in the Permit, admittedly inadequate to meet water quality standards, was exceeded several times.”

For toxic, priority pollutants discharged by TransAlta, the Fact Sheet is confusing. It appears that, 

according to an April 2010 report to Ecology by TransAlta, TransAlta does not meet no-detect 

requirements for: arsenic, copper, lead, nickel, selenium, and zinc. Fact Sheet at p. 23. Further, Ecology 
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

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finds that there is a reasonable potential for TransAlta’s discharge of pollutants to violate water quality 

standards for chlorine, chromium and selenium. Ecology discloses that it was unable to determine 

whether TransAlta’s discharge of pollutants will violate or have the potential to violate water quality 

standards for copper, lead, nickel, and zinc. The Fact Sheet discloses only that Ecology was unable to so 

determine due to “lack of data.” There is no information as to why the data was lacking, especially given 

TransAlta’s permit renewal obligation to supply adequate data.

All of these pollutants are of significant concern, some for human health, but especially for aquatic 

ecosystem health. For example, copper interferes with salmonids’ (and likely other fish) olfactory 

abilities which in turn affects predator avoidance and other functions upon which the fish depend on a 

heightened sense of smell. The National Marine Fisheries Service, based upon research it has participated 

in, advises that copper causes these adverse effects in salmon at levels as low as 2 ug/L, which level is 

more stringent than Washington’s numeric criteria for copper. 

Based upon this research, in order to be protective of designated uses for salmonids and other fish in 

Hanaford Creek and the Skookumchuck River and to meet narrative water quality standards, Ecology 

must apply a 2 μg/L criteria for copper and impose effluent limits in this Permit sufficient to comply with 

that criteria.” Selenium contamination, especially in conjunction with mercury (also present in coal plant 

discharges), contributes to increased mortality, reduced growth, and reproductive failures in fish. The 

footnote on page 10 of the comments states that “See, e.g., A. Dennis Lemly, “Pathology of Selenium 

Poisoning in Fish”, Environmental Chemistry of Selenium, 281, 282 (William T. Frankenberger, Jr. & 

Richard A. Engberg, eds.,1998); Dennis A. Lemly, Aquatic Cycling of Selenium: Implications for Fish 

and Wildlife, 5 UDOI FWS Fish and wildlife Leaflet 12 (1987); Dennis A. Lemly, Symptoms and 

Implications of Selenium Toxicity in Fish: The Belews Lake Case Example, Aquatic Toxicology 57 

(2002).” The selenium in the industrial process wastewater is likely increased when the industrial 

wastewater is routed through the mine pits during the summer months.

Despite these findings, the Permit does not set new or more stringent limits for chromium or chlorine. In 

fact, the maximum daily limit for total residual chlorine increases from the last version of the permit to 

this Permit; from 0.20 mg/L to 0.50 mg/L. Fact Sheet at p. 25. The Permit sets no limit for selenium or 

any of the other priority pollutants other than retaining the continuously-violated “no-detect” limit for the 

cooling tower blowdown.

This is confusing. In the Fact Sheet, the no-detect limit is represented as for cooling tower blowdown 

with no apparent limits for the other waste streams. However, there is no internal outfall to which the 

cooling tower blowdown requirements apply. Rather there is only one outfall to Hanaford Creek and it 

appears from the Permit that the no-detect limit applies at the 001 outfall. The actual limits and their 

basis need to be clarified.” Rather, for all of these pollutants, including those Ecology has determined 

have the reasonable potential to violate water quality standards (and that have been violating water quality 

standards), Ecology requires a study, to be completed in 2013. Fact Sheet at pp. 21 and 23; Permit at 

S.11. There are no requirements that the study result in limits or impose particular treatment 

technologies. There is no requirement in the Permit for implementation of study results. Finally, there is 

no reference to the EPA Final Study which already sets forth treatment technologies that work for many, 

if not all, of these pollutants.

Ecology’s Response

The permit that Ecology issued to TCG in June 2005 required the Permittee to meet the non-detect levels 

for all priority pollutants, except zinc and chromium (Cooling Tower Blowdown criteria- 40 CFR 423, 

page 15 of the fact sheet) at the discharge point (outfall 001). Ecology’s permit renewal analysis found 

that some priority pollutants were detected in the TCG’s effluent and they were: antimony arsenic, 
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copper, lead, nickel, selenium, and zinc. Since TCG violated the non-detect limits for the above 

pollutants, Ecology has given TCG a compliance schedule to meet these non-detect requirements. 

In response to the Earthjustice comment that Ecology was unable to determine whether surface water 

quality standards for copper, lead, nickel and zinc were violated, this result occurred due to not having 

data on the hardness of the receiving water. The hardness data was not a requirement in the permit of 

2005 because it used technology based limits and not water quality standards for these priority pollutants. 

In this permit, Ecology is requiring TCG to collect hardness data and this will be used by Ecology to 

establish site specific water quality criteria and evaluate the reasonable potential for these pollutants. In 

the absence of Washington State surface water quality standards for these pollutants, Ecology used EPA 

National recommended water quality standards in a memo dated June 7, 2010, to conduct the reasonable 

potential analysis for copper, lead, nickel and zinc. This analysis revealed that TCG will not exceed 

surface water quality standards for lead, nickel and zinc. On the other hand, copper is expecting to 

exceed the surface water quality standards (See Table 4 of this fact sheet in Appendix C). Based on these 

results, Ecology has established effluent limits for these parameters (See Table 1 of the permit). These 

effluent limits will be effective December 1, 2014.

In response to the Earthjustice comment that Ecology does not set new or more stringent limits for 

chromium or chlorine and that the chlorine limit was raised, it is true that Ecology changed the chlorine 

limit to correct a mistake made in the 2005 permit. The current limit for chlorine is the limit stated in 

40CFR 423. After reconsideration, Ecology has determined that the effluent of 0.20 mg/L is reasonably 

met by TCG and will be maintained as a performance based limit until a WQBEL is established.

Ecology has added in the permit that TCG evaluate the cooling tower blowdown separately as specified in 

the 40 CFR 423. This is part of the compliance schedule and the Permittee is required to submit the 

results of this evaluation (cooling tower blowdown evaluation). Ecology has determined at this time that 

the permittee must monitor outfall 001 and adhere to the cooling tower blowdown effluent limits at the 

discharge point to protect the receiving water body (Hanaford Creek) from the priority pollutants. These 

interim limits will be in place until the final effluent limits are implemented.

The prior permit as well as this new permit requires the Permittee to conduct and report the Whole 

Effluent Toxicity (WET) tests. These tests ensure that all toxic effects from pollutants are accounted for 

in the wastewater effluent. If these tests indicate that toxicity exists in the wastewater, then Ecology 

requires the Permittee to treat the wastewater and remediate the problem.

Action Taken:

1. Evaluation of the cooling tower blowdown waste stream separately as specified in the 40 CFR 423

2. Chlorine permit limit changed from 0.50 mg/L to 0.20 mg/L

Comment 7

THE PERMIT FAILS TO CONFORM TO REQUIREMENTS OF THE CLEAN WATER ACT AND 

WASHINGTON LAW

The Conservation Organizations object to issuance of the Permit as proposed. The Permit fails to apply 

BAT and AKART, allows for the violation of water quality standards, fails to properly apply 

antidegradation requirements, and results in backsliding.

Comment 7A
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The Permit Does Not Require BAT and AKART

BAT and AKART must be required in the Permit regardless of the status of the receiving waters and the 

discharge’s effects on the water. The Permit reflects no analysis or determination of best treatment 

technologies or of all known and reasonable treatment technologies for the pollutants and waste streams 

at issue. The EPA Final Study and June 2010 Guidance clearly demonstrate and find that settling ponds 

(even with some chemical treatment for some pollutants) are not BAT for steam generating electrical 

plants like TransAlta. The Final Study clearly demonstrates and EPA finds that the treatment 

technologies in use at TransAlta’s coal plant cannot achieve the purported “no detect” limits in the Permit 

and likely cannot achieve the limits for chromium. Ecology cannot rely solely on the cooling tower 

blowdown effluent limitation guidelines for pollutant control requirements. Rather, Ecology should, 

consistent with the EPA Final Study and June 2010 Guidance, require additional treatments such as 

biological treatment and/or the zero discharge treatments already in use at other facilities in the U.S. and

Europe for TransAlta’s industrial waste streams (including coal pile runoff.)

Ecology’s Response

This existing and new permit requires BAT for all industrial processes at the TCG site. The requirements 

for the cooling tower blowdown which are based on BAT also apply to all other waste streams at the TCG 

site. In this new permit TCG is required to perform studies which will lead to future AKART limits 

which meet the state surface water quality standards for the parameters that currently TCG has potential 

to exceed. This type of detailed analysis is allowed under federal and state laws in order to give the 

Permittee time to evaluate the AKART.

The priority pollutant analysis that the Permittee submitted to Ecology showed that the Permittee has met 

most of the non-detect levels requirements (see Table 2 of appendix C of the fact sheet). This indicates 

that the TCG settling ponds in combination with chemical treatment has achieved compliance with the 

majority of the technology based requirements and limits. 

For the pollutants that were detected in the effluent wastewater, Ecology conducted a reasonable potential 

analysis against surface water quality standards. Based on this analysis, Ecology determined that there is 

a reasonable potential that the Permittee would exceed the surface water quality standards for certain 

pollutants (See Table 3 and 4 in Appendix C). Based on the reasonable potential analysis, Ecology has 

established final effluent limits (See Table 1- Final Effluent Limits, of the permit) and given TCG a 

compliance schedule. These final effluent permit limits will be effective December 1, 2014. 

Action Taken:

TCG does treat the WFGD blowdown by a lime precipitation, polymer chemical coagulation/

flocculation, and sedimentation system. See Ecology’s response to comment 1.

Comment 7B

The Permit Violates 40 C.F.R. 122.44(d) and WAC 173-220-130.

Ecology has already found that the TransAlta discharge violates (and has been violating) water quality 

standards for chromium and chlorine and has the reasonable potential to violate water quality standards 

for selenium. It is likely that the discharge violates narrative water quality standards for copper given that 

the testing shows copper at or in excess of the 2 μg/L that can adversely affect fish. 
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The Conservation Organizations are further concerned regarding sulfates. Washington does not have a 

numeric water quality standards for sulfates, therefore, the narrative standard applies to protect designated 

uses of Hanaford Creek and other downstream waters. 40 C.F.R. § 122.44(d)(1)(vi) requires states to 

assess pollutants against narratives standards and designated uses, and if the pollutant has the reasonable 

potential to cause a violation of the narrative standard, to set calculated effluent limits designed to attain 

the narrative standard. It is unclear to what extent Ecology has properly assessed sulfate against its 

narrative criterion.” Further, Ecology has failed to actually make a proper reasonable potential 

assessment in that it has not made the effort to acquire data necessary to make such an assessment, as it 

appears that TransAlta’s discharge may violate water quality standards for lead, nickel, and zinc.

Ecology fails to impose limits in the Permit sufficient to ensure that water quality standards are met, in 

violation of 40 C.F.R. § 122.44(d) and WAC 173-220-130. Rather, Ecology requires only a three-year 

study and no implementation of any actual pollutant limits. This is particularly egregious given EPA’s 

Final Study demonstrating that biological treatment or zero discharge technologies can remove many of 

these pollutants. There is no need for a study. The study will simply serve to delay what is required now 

for this Permit. The work has already been done by EPA.

A compliance schedule may not be used in this case for some, if not all, pollutants. After July 1, 1977, 

NPDES permits must require immediate compliance for effluent limitations that are based on water 

quality standards adopted before July 1, 1977. For standards adopted after that date, Ecology may allow 

compliance schedules only if they have first clearly indicated in its water quality standards submitted to 

EPA that it intends to allow compliance schedules for meeting WQBELs. See EPA Memorandum 

“Compliance Schedules for Water Quality-Based Effluent Limitations in NPDES Permits,” May 10, 

2007, copy enclosed [citing In the Matter of Star-Kist Caribe, Inc., 3 E.A.D. 172, 175, 177 (1990)]. To 

the extent that any of the standards in question (including narrative standards) were adopted prior to July 

1, 1977, Ecology cannot allow a compliance schedule for TransAlta to meet WQBELs necessary to 

achieve or maintain those standards. For standards adopted after July 1977, Ecology must comply with 

the requirements for compliance schedules set forth in the EPA May 2007 Memorandum.

The study is decidedly not a “compliance schedule.” It is wholly inconsistent with requirements for 

compliance schedules. Under both federal and state permitting requirements, a compliance schedule must 

bring a permittee into compliance as soon as possible, but not later than applicable CWA statutory 

deadlines, and it must do so with interim deadlines requiring specific actions. 40 C.F.R. § 122.47; WAC 

173-220-140. As stated by EPA in its May 2007 Memorandum, any compliance schedule in an NPDES 

permit must be an “enforceable sequence of actions or operations leading to compliance with a [water 

quality-based] effluent limitation [“WQBEL”] as required by the definition of “schedule of compliance in 

section 502(17) of the CWA.” EPA May 2007 Memorandum, p. 2 (emphasis added.) EPA emphasizes 

throughout the memorandum that schedules of compliance must actually set and require compliance with 

the WQBEL. Id. Further, EPA sets out very specific findings before a compliance schedule is warranted, 

none of which have been made here. Finally, EPA is clear that compliance schedules cannot be used to 

wait for completion of TMDL studies or for the development of Use Attainability Analyses.

The provisions in the permit regarding a study are not a compliance schedule as they do nothing to bring 

TransAlta into compliance with the requirement of the Clean Water Act to apply BAT and WQBELs or 

with state law to comply with AKART. Further, TransAlta has three years to complete a study of 

information that should have been developed and provided as part of TransAlta’s permit renewal 

application obligations. There is nothing in the record demonstrating that it takes three years to develop 

and implement a study that is primarily simply characterizing TransAlta’s waste. Waiting for the study is 

akin to waiting for a TMDL or UAA. Finally, and most importantly, the study is entirely unnecessary in 

light of EPA’s Final Study regarding coal plant wastewater. Ecology must amend the permit to provide 

for BAT and AKART and set actual WQBELs.
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Ecology’s Response

Ecology’s new draft permit analysis found that some priority pollutants were detected in the TCG’s 

effluent and they were antimony, arsenic, copper, lead, nickel, selenium, and zinc. Since TCG violated 

the non-detect limits for the above pollutants, Ecology has given TCG a compliance schedule to meet 

these non-detect requirements. 

In response to the Earthjustice comment that Ecology was unable to determine whether water quality 

standards for copper, lead, nickel and zinc were violated, this result occurred due to not having data on 

the hardness of the ambient water. The hardness data was not a requirement in the permit of 2005 

because it used technology based limits and not water quality standards for these priority pollutants. In 

this permit, Ecology is requiring TCG to collect hardness data and this will be used by Ecology to 

evaluate the reasonable potential for these pollutants. This proposed permit has non-detect interim limits 

for all priority pollutants except zinc and chromium. In the absence of Washington State surface water 

quality standards for these pollutants, Ecology used EPA National recommended water quality standards 

in a memo dated June 7, 2010, to conduct the reasonable potential analysis for copper, lead, nickel and 

zinc. This analysis revealed that TCG will not exceed surface water quality standards for lead, nickel and 

zinc. On the other hand, copper is expecting to exceed the surface water quality standards (See Table 3 of 

this fact sheet). Based on these results, Ecology has established effluent limits for these parameters (See 

Table 1 of the permit). This will be effective in the next permit cycle of 2015.

Ecology has determined that BAT is met by the inclusion of federal effluent guidelines technology based 

limits. Furthermore Ecology has determined that the WFGD blowdown discharge meets AKART with 

the lime coagulation/flocculation/sedimentation treatment system.

Action Taken: None

Comment 7C

The Permit Violates Federal Requirements For Variances From Water Quality Standards And For 

Downgrading of Water Quality

Because the Permit fails to include limits necessary to ensure that water quality standards are met in 

receiving waters, and because the Permit does not include a valid compliance schedule, the Permit allows 

a variance from water quality standards for at least the term of the Permit and will allow for the 

downgrading and failure to protect beneficial uses for the term of the Permit. Given these circumstances, 

Ecology has failed to comply with the requirements of 40 C.F.R. §§ 131.1, 131.10(g), 131.10(h) and the 

EPA NPDES Permit Writers Manual and EPA Water Quality Standards Handbook.

Federal law and permitting requirements are clear on when a state may allow a variance from water 

quality standards or under what circumstances a state may allow a downgrading of a waterbody. EPA’s 

NPDES Permit Writers Manual, chapter 10 sets forth the procedures and requirements for state or EPA 

permit writers when assessing a variance like the one that will effectively be in place for TransAlta in this 

Permit. Section 10.2.3 provides:

Water quality standards variances require similar substantive and procedural requirements as removing a 

designated use, but unlike use removal, variances are both discharger and pollutant specific, are timelimited, and do not forego the currently designated use of a water body. A variance is appropriate where 

the state believes that the standard can be ultimately attained. By maintaining the standard rather than 
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changing it, the state will assure that further progress is made in improving the water quality and attaining 

the standard.

USEPA NPDES Permit Writers Manual, EPA 833-B-96-003, Office of Water (Dec. 1996). See also 

USEPA Water Quality Standards Handbook: Second Edition, EPA 823-B-94-005a, Office of Water, § 2.7 

(updated July 2007).

Removal of a use or granting of a variance is subject to very specific conditions. To remove a designated 

use (or grant a variance from water quality standards) the state must adhere to 40 C.F.R. § 131.10(g). 

There is no demonstration here that Ecology has applied the factors and done the analysis required for a 

variance from water quality standards for TransAlta. Moreover, given the factors required for such 

analysis, and given that technology standards have not been met in this Permit, Conservation 

Organizations assert that a variance (or a downgrading in the use) is not supported in this case and the 

Permit should not allow the implicit variance that is currently part of the proposed Permit.

Ecology’s Response

Ecology is not removing the applicable federal requirements. Ecology is requiring the Permittee to 

comply with the surface water quality standards in accordance with a compliance schedule. The 

compliance schedule provides a timeline for the Permittee to conduct AKART analysis and ultimately 

comply with the water quality standards. Ecology has modified the compliance schedule from the PNOP 

draft permit and this new compliance schedule reflects the requirements under the Federal Water 

Pollution Control Act, Section 301, 40 CFR 122.47 and WAC 173-220-140. 

Action Taken: Modified the compliance schedule to conform with the federal and state laws

requirements. 

Compliance Schedule

The following compliance schedule is designed to provide guidance to the permittee to meet the 

effluent limits that permittee was unable to attain and the surface water quality standards that the 

permittee has potential to exceed

1. Submit cooling tower blowdown evaluation as specified under 40 CFR 423, by March 1, 2011.

2. Submit draft AKART/engineering report to address the technology based wastewater effluent 

limits (currently the permittee is unable to meet) and surface water quality standards (the 

permittee has potential to exceed), by December 1, 2011.

3. Ecology review draft AKART/engineering report and provide comments by February 1, 2012.

4. Submit final engineering report by December 1, 2012.

5. Ecology approves final engineering report by March 1, 2013.

6. Complete the implementation of final engineering report by March 1, 2014.

7. New proposed final effluent limits effective December 1, 2014.

Comment 7D

A Mixing Zone Is Inappropriate For These Pollutants And For Hanaford Creek.
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As noted above, it is not clear that a mixing zone has been applied in this Permit. In the event a mixing 

zone is contemplated, Conservation Organizations object to allowance of a mixing zone when TransAlt a 

has not been required to fully apply BAT or AKART prior to being allowed a mixing zone. Conservation 

Organizations also object to any mixing zone for toxic and accumulative pollutants such as copper or 

mercury or ammonia or pollutants that accumulate and express problems downstream such as nutrients. 

A mixing zone is also inappropriate where, as here, anadromous fish use the receiving water. 

Conservation Organizations further object to any mixing zone that fails to follow the constraints of WAC 

173-201A-400 to meet the most restrictive combination of the following:

The mixing zone may not extend in a downstream direction for a distance from outfall 001 greater than 

three hundred feet plus the depth of the water over outfall 001, or extend upstream for a distance of over 

one hundred feet;

The mixing zone may not utilize greater than 25% of the flow; and The mixing zone may not occupy 

greater than 25% of the width of the water body.

Ecology’s Response

In the new proposed permit, Ecology has not authorized a mixing zone for Outfall 001 discharge. This 

language has been amended to clarify this finding.

Action Taken: Permit language clarified to assign no mixing zone.

Comment 7E

The Permit Appears To Violate the Anti-Backsliding Provisions of the Clean Water Act

The proposed Permit appears to include a less-stringent maximum daily effluent limitation for chlorine 

than was previously required. The previous permit imposed a maximum daily effluent limit for chlorine 

of 0.20 mg/L. The proposed Permit relaxes the maximum daily effluent limit for chlorine to 0.50. Fact 

Sheet at p. 25. This is particularly troublesome given the evidence in Ecology’s file that at 0.20 mg/L 

TransAlta was causing or contributing to violations of the water quality standard and the evidence that 

TransAlta has violated the chlorine limit in the past. It appears Ecology is allowing TransAlta to address 

those problems by simply relaxing the limit. This violates 33 U.S.C. § 1342(o).

Ecology’ Response

The permit of 2005 was in error in imposing a limit of 0.20 mg/L for chlorine. It should have been 0.5 

mg/L as stated in 40 CFR 423. This is addressed in the TCG’s fact sheet please see page 15 of the draft 

permit fact sheet, Technology based limits. This change in the chlorine limit is not backsliding. After 

reconsideration, Ecology has determined that the effluent of 0.20 mg/L is reasonably met by TCG and 

will be maintained as a performance based limit until a WQBEL is established.

Action Taken: Chlorine effluent limit changed from 0.50 mg/L to 0.20 mg/L

Comment 7F

The Antidegradation Analysis Is Inadequate
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First, Ecology has not applied AKART or BAT to TransAlta’s discharges which alone appears to violate 

Ecology’s antidegradation policy. WAC 173-201A-300(2)(d).

Second, the Fact Sheet for the Permit flatly states that Tier I (WAC 173-301A-310) applies to this Permit. 

There is no discussion or explanation or evidence as to why, on a pollutant by pollutant basis, this is the 

case as opposed to Tier II. Further, it is apparent from the information in the Fact Sheet and file that in 

fact this Permit will violate even Tier I requirements in that Ecology has determined that for some 

pollutants there is a reasonable potential to violate (not just degrade towards) water quality standards and 

for others Ecology has not made the determination. There is no indication of “appropriate and definitive 

steps to bring the water quality back into compliance with water quality standards” in this Permit.

Further, as noted above, TransAlta discharges under three different NDPES permits. This Permit and 

Permit 0037338 are interconnected in that wastewater from this Permit is sometimes discharged through 

Permit 0037338. There is no indication in the record that a proper, cumulative antidegradation analysis 

has been done, not just for impacts to Hanaford Creek from multiple discharge points from the totality of 

TransAlta’s discharges, but also to the Skookumchuck River.

Ecology’s Response

The existing and new permits require BAT for all industrial processes at the TCG site. It is not accurate 

to state that Ecology has not applied AKART or BAT to TCG discharges and that this violates Ecology’s 

antidegradation policy. The requirements for the cooling tower blowdown are based on BAT and also 

apply to all other waste streams at the TCG site. In this new permit TCG will be required to perform 

studies which will lead to potential future AKART limits. It is inaccurate to say that this permit does not 

require AKART because Ecology is intending to implement more stringent WQBELs once further 

investigation is completed. This type of detailed analysis is allowed under federal and state law in order 

to give the Permittee time to evaluate AKART, and meet the surface water quality standards that currently 

TCG has potential to exceed.

Tier II antidegradation requirements only apply to “new or expanded actions ... that are expected to cause 

a measurable change in the quality of the water.” TCG’s discharge is not a new or expanded action, and 

Tier II requirements therefore do not apply to TCG’s discharge. Ecology believes Tier I antidegradation 

requirements are met because TCG’s NPDES permit includes water quality based effluent limits and 

other requirements that will maintain and protect existing and designated uses in the receiving water. 

Action Taken: None

Comment 8 – Summary

ECOLOGY MUST REVISE THE PERMIT

The Conservation Organizations request that Ecology revise the proposed Permit or otherwise take action 

as follows:

Assess and impose BAT (for example, biological treatment or zero discharge treatment) in 

accordance with EPA’s Final Study and June 2010 Guidance;

Assess and impose AKART (for example, biological treatment or zero discharge treatment);
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Impose Water Quality Based Effluent Limits in accordance with 40 C.F.R. § 122.44(d) for 

chlorine, chromium, selenium, copper (for copper, Ecology should impose an effluent limit below 

2 μg/L in order to protect fish habitat and uses), lead, nickel, and zinc;

Assess the need for a WQBEL for sulfate and impose an effluent limit if necessary;

Perform antidegradation analysis consistent with the requirements of federal and state law and 

cumulatively for impacts to Hanaford Creek and the Skookumchuck River from all Transalta’s 

discharges;

Impose a 0.20 maximum daily limit for chlorine or more stringent limits as necessitated by 40 

C.F.R. § 122.44(d) (addressing the backsliding issue);

Disallow a mixing zone (to the extent that this is currently contemplated or allowed); and

Assess TransAlta’s discharge and limits under this Permit together with the mine pit and landfill 

permits or consolidate this permit with the mine pit permit

Ecology’s Response

Please see Ecology’s responses 1 through 7

Action Taken: None
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COMMENT RECEIVED FROM QUINAULT INDIAN NATION JULY 9, 2010

Comment 1

As the TransAlta site is considered a major NPDES facility that appears to not have had any inspections 

conducted in the most recent NPDES permit, Ecology should perform multiple site inspections during the 

new NPDES permit five year period to gather information on the TransAlta facilities, to gather 

independent water quality samples, and confirm that past observed exceedences of permit limits does not 

constitute a more frequent problem for water quality and QIN treaty sources.

Ecology’s Response

Ecology conducted four non-sampling inspections during the current five year permit cycle. In the next 

five year permit cycle, Ecology will conduct more than one inspection and one would include sampling.

Action Taken: In the next five year permit cycle, Ecology will conduct more than one inspection and one 

would include sampling.

Comment 2

Ecology should identify in the current permit renewal whether the agency conducted any site inspections, 

any actions Ecology considered during the review of the expired permit that would either identify and/or 

address TransAlta activities to reduce or eliminate past exceedences of permit limits or water quality 

standards.

Ecology’s Response

Ecology conducted four non-sampling inspections during the current five year permit cycle. Ecology’s 

proposed draft permit has evaluated the Permittee’s effluent characteristics against the surface water 

quality standards and they are discussed on page 23 of the fact sheet of proposed draft. Also appendix C 

shows the violation history, priority pollutant detection levels and the reasonable potential analysis. 

Ecology has given the Permittee a compliance schedule to meet the surface water quality standards.

Action Taken: Please see Ecology’s response to Earthjustice comment 7C

Comment 3

Ecology should not increase the new discharge permit limit for total chlorine but rather maintain past 

permit limits for this quality parameter.

Ecology’s Response

Ecology has corrected a mistake in the 2005 permit for the chlorine limit for the discharge to conform 

with the 40 CFR 423-BAT limits, please see page 15 of the draft fact sheet. After reconsideration, 

Ecology has determined that the effluent of 0.20 mg/L is reasonably met by TCG and will be maintained 

as a performance based limit until a WQBEL is established.

Action Taken: Chlorine effluent limit changed from 0.50 mg/L to 0.20 mg/L

Comment 4
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Based on the number of metal exceedences from just one sample event, potential harm to aquatic life and 

likely not being consistence with the antidegradation provision of the Clean water Act, Ecology should 

require TransAlta to take annual priority samples and should undertake every effort in the new draft 

permit to ensure outfall001 discharges do not exceed water quality standards or permit levels (Table 2 of 

the draft permit). Ecology should also require TransAlta to identify the facility practices that contribute 

to these discharges and to seek practical ways to reduce these discharges to protect water quality and 

designated uses. Lastly, Ecology should require TransAlta in this NPDES permit renewal to immediately 

undertake actions to reduce discharges of priority pollutant metals to Hanaford Creek that were 

documented to exceed standards in the last permit.

Ecology’s Response

Please see Ecology’s response to Earthjustice comment 7A.

Action Taken: None

Comment 5

While not certain, it is likely (depending on liner exists and the nature of the liner) that Pond 3E may be 

hydraulically connected to Hanaford Creek (pond waters to groundwater, and groundwater moves 

downgradient and discharges to surface water). If this is the case and depending on the geologic 

characteristics of the deposits present, it is possible that pond 3E may discharge to Hanaford Creek. If 

this is the case and pond 3E is located close Hanford Creek in geologic materials with a high hydraulic 

conductivity, it is conceivable that this pond may not cool outfall 001 waters to meet permit limits or 

water quality standards for Hanaford Creek.

Thus, we request Ecology require TransAlta to document conditions of pond 3E, including the nature of 

any pond liner (hydraulic conductivity and engineering design), The hydraulic conductivity of the 

geologic materials present at pond 3E and down gradient toward Hanford Creek, and examine the 

potential for TransAlta wastewater discharges to pond 3E to harm Hanaford Creek water temperatures or 

exceed proposed permit limits. This may require characterization of alluvial materials present at pond 3E 

and in/adjacent to Hanford Creek and to conduct additional surface water monitoring for water 

temperature n Hanaford Creek (upstream and downstream of pond 3E). If pond 3E’s discharge is found 

adversely impact Hanaford Creek water temperature, the QIN would request that Ecology require 

TransAlta to cease such discharges and relocate the current location of outfall 001 to a larger nearby 

waterbody (Skookumchuck River is a possibility) where meeting permit limits and water quality 

standards may be attainable due to greater stream discharge.

Ecology’s Response

Comments noted

Action Taken: Ecology will investigate this issue.

Comment 6

The QIN supports raising TransAlta’s permit limit for DO vial outfall 001 as this higher value is more 

conducive to salmonid survival and maintaining habitat quality for the rearing needs of juvenile Coho 

salmon.

Ecology’s Response
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Comments noted

Action Taken: None
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TransAlta Centralia Generation LLC submitted comments on July 8, 2010

Comment 1

Page 6, Condition S 1.A, Table 1, Lines 2 and 9 The draft permit contains proposed limits for Dissolved 

Oxygen (DO) and Temperature at Outfall 001 based upon the water quality standard for "Core Summer 

Salmonid Habitat" at WAC 170-201A200(1 )(d) for "Hanaford Creek and all the tributaries from the east 

boundary of Sec. 25-T15N-R2W (river mile 4.1) to the unnamed tributary at latitude 46.7295 longitude -

122.6812 except where designated Char." This reach, which includes the TransAlta's Outfall 001, has 

been identified by the Department as incorrectly listed as "Core Summer Salmonid Habitat". It should be 

listed as "Salmonid Spawning, Rearing, and Migration" (See attached e-mail message from Susan Braley 

dated July 1, 2010). Therefore the DO and Temperature limits in the permit for the Outfall 001 should be 

based upon "Salmonid Spawning, Rearing, and Migration" requirements.

Ecology’s Response

The temperature and dissolved oxygen limits in the proposed permit are based on WAC 173-201A which 

currently has temperature set at 16.0 oC and dissolved oxygen at 9.5 mg/L for Hanaford Creek. If these 

temperature and DO limits for Hanaford Creek are revised to 17.5 oC for temperature and dissolved 

oxygen to 8.0 mg/L, these interim limits will be adjusted to reflect this regulation change.

Action Taken: None

Comment 2

Page 6, Condition S 1.A, Table 1, Line 2 The draft permit contains a proposed limit for Dissolved 

Oxygen (DO) at Outfall 001 that is listed as "Minimum, 9.5 mg/L" as a monthly average. As noted 

above, this should be based upon the water quality standard for "Salmonid Spawning, Rearing, and 

Migration" which is "Minimum, 8.0 mg/L". TransAlta has limited data for Dissolved Oxygen in 

Hanaford Creek during the summer period, but the data submitted to the Department indicates that the 

DO in the creek may be lower than 8.2 mg/L at times during the year. Therefore, the standard at WAC 

170-201A-200(1)(d)(i) should be included in the limit for situations when the natural conditions in the 

creek (or the plant effluent) does not achieve 8.0 mg/L, just as the temperature limit in the permit 

currently incorporates 170-201A-200(1)(c)(i) and 170-201A-200(1)(c)(ii). The permit should not require 

a specific DO at Outfall 001, but instead should require Outfall 001 not to decrease DO in the stream by 

more than 0.2 mg/L. This would be applied through upstream and downstream DO monitoring to 

document the DO in Hanaford Creek just as the temperature limit is expressed in allowable increase in 

temperature of the creek.

Ecology’s Response

The temperature and dissolved oxygen limits in the proposed permit are based on WAC 173-201A which 

currently has temperature set at 16.0 oC and dissolved oxygen at 9.5 mg/L for Hanaford Creek. If these 

temperature and DO limits for Hanaford Creek are revised to 17.5 oC for temperature and dissolved 

oxygen to 8.0 mg/L, these interim limits will be adjusted to reflect this regulation change. Ecology has

set this permit’s DO limits based on WAC 173-201A water quality criteria. At this point, Ecology does 

not have sufficient information to alter the water quality criteria for DO.

Action Taken: None
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 65 of 70

Comment 3

Page 6, Condition S 1.A, Table 1, Line 11-The draft permit contains limits for "priority pollutants less 

chromium and zinc" at Outfall 001 that are listed as "No detectable amount". The basis for the limit, as 

described on page 23 of the Fact Sheet, is incorrectly stated as "40 CFR 423 requires that the Permittee 

must achieve non-detectable levels for the priority pollutants (priority pollutant less chromium and zinc) 

for the cooling tower blow down discharge before this water is discharged to the surface water (Hanaford 

Creek)." This section of the Fact Sheet (II E) is discussing the basis for surface water quality based 

limits, not technology based limits. The condition in Table 1 of the permit related to Outfall 001 should 

address compliance with the surface water quality standards. Additionally, it is clear that the technology 

based standard does not require "No detectable amount" of the priority pollutants at Outfall 001.

The referenced standard, as quoted on pages 15-16 of the Fact Sheet, states at 40 CFR 423.13(d)(1) "The 

quantity of pollutants discharged in cooling tower blowdown shall not exceed the quantity determined by 

multiplying the flow of cooling tower blowdown times the concentrations listed below: The 126 priority 

pollutants contained in chemicals added for cooling tower maintenance, no detectable amount, 

except:" Chromium, total and Zinc, total. Additionally, 40 CFR 423 .13( d)(3) states "At the permitting 

authority's discretion, instead of the monitoring specified in 40 CFR 122.11(b) compliance with the 

limitations for the 126 priority pollutants in paragraph (d)(1) of this section may be determined by 

engineering calculations which demonstrate that the regulated pollutants are not detectable in the final 

discharge by the analytical methods in 40 CFR part 136."

It is clear that this standard is intended to prohibit power plants from adding chemicals containing the 

priority pollutants for cooling tower maintenance in quantities that would result in a detectable amount of 

any added chemical that is a priority pollutant being discharged to Outfall 001. We suggest that Line 11 

of Table 1 be eliminated and the technology based standard be applied through a study under condition S 

1l as described at 40 CFR 423.13(d)(3). However, if the Department feels that a technology based limit 

on priority pollutants is required, we suggest that language of 40 CFR 423. 13(d)(1) be used to address 

the technology based standard. Suggested language is: "No amount of the 126 priority pollutants in 

Appendix B of this permit can be contained in chemicals added for cooling tower maintenance that will 

result in a detectable amount in the discharge". We believe that this language will clarify where the basis 

for the requirement for "No detectable amount" comes from and allow TransAlta and the Department to 

address this requirement through a study under condition S 11. If the Department feels a water quality 

based limit on Outfall 001 is required, it should not use the "No detectable amount" language that applies 

for added cooling tower maintenance chemicals but should instead use a limit based upon the water 

quality standards in WAC 173-201A-240 for any chemicals relating to Outfall 001, not the list of 126 

priority pollutants in 40 CFR 423.

Ecology’s Response

The fact sheet has addressed EPA’s guidelines for the cooling tower blowdown industrial process. 

Ecology has used the BAT guidelines for the cooling tower blowdown as the standard for all industrial 

process waste streams for the TCG NPDES permit at this time. In the new proposed permit the cooling 

tower blowdown pollutant limits are applied as an interim permit limits. Ecology will revise and adjust 

the final permit limits based on the AKART analysis required in the compliance schedule of new 

proposed permit. 

Action Taken: None
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 66 of 70

Comment 4

Page 6, Condition S 1.A, Table 1- It should be clarified for DO, Temperature, and Turbidity that 

background readings are taken upstream of Outfall 001 and compared to the downstream reading to 

determine compliance. Perhaps an additional footnote on the conditions for DO, Temperature, and 

Turbidity explaining the monitoring locations would clarify the requirement. If necessary, TransAlta can 

provide the coordinates for the upstream and downstream monitoring locations currently used.

Ecology’s Response

Changes are made in the new proposed permit. This permit adds the location for the background 

sampling for Turbidity and Temperature. Ecology is not changing the permit requirements for DO.

Action Taken: Permits adds the location for the background turbidity and temperature.

Comment 5

Page 7, Condition S 1.A, Table 2, Line 3 There appears to be an error in the units on the Fecal Coliform 

Bacteria limit. We believe the units on the limit should be expressed in "#/100 mL" instead of"#/mL".

Ecology’s Response

It is a typographical error. The fact sheet of the draft permit has the correct unit (see page 26 of the fact 

sheet). The unit for fecal coliform in the permit is changed from #/mL” to “#/100 mL”

Action Taken: Fecal coliform unit corrected in the permit

Comment 6

Page 7, Condition S1.A, Table 2 - The reference "b" on the header "Maximum dailyb" in Table 2 appears 

to be referring to footnote "b" of Table 1. A footnote "b" similar to Table 1 should be added in Table 2 for 

"Maximum daily" and the other references in the table corrected as necessary.

The current footnote "b" correctly references the proper sampling location for BOD. However, it should 

include references for sampling Fecal Coliform Bacteria, Total Chlorine residual, and pH at the same 

sampling location. These parameters in the table should also get the reference to the footnote for the 

sampling location at the outlet of the oxidation pond.

Ecology’s Response

Corrections are made in the permit (please see page 8 table 3 of the permit).

Action Taken: Footnotes added/clarified regarding the effluent sampling collection location

Comment 7
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 67 of 70

Condition S2.A The draft permit increases the frequency for testing Chromium, Zinc, and Hardness in 

Outfall 001 from annually to monthly. Since test data submitted annually for the previous permit have 

shown the results for Chromium and Zinc to be well below the permit limits in condition S 1.A, 

continuing the testing requirement at once per year will give the Department enough data to document 

continued compliance with these limits. If the Department is concerned about compliance with the water

quality standards for Chromium and Zinc (which vary depending upon water hardness), testing twice per 

year (once in the winter and once in the summer) for these parameters (including hardness at the same 

time) will give the Department enough data to document compliance with these standards.

Ecology’s Response

Ecology determined that in order to have a good pool of data for Chromium, and Zinc, it is necessary to 

conduct the effluent testing monthly. Therefore the sampling frequency will remain as stated in the draft 

permit (except hardness). Ecology has changed hardness monitoring frequency from monthly to 

quarterly. This frequency of sampling is a common criteria in many NPDES permits administered by 

Ecology.

Action Taken: None

Comment 8

Condition S 11.A The language in this condition, "This work plan will address methods to meet the 

surface water quality standards (WAC 173-201) and technology based limits to achieve the applicable 

permit limits that currently permit is unable to attend" implies that the plant currently does not meet the 

water quality and technology based limits. We believe that we currently do meet all the technology based 

limits in 40 CFR 423.13(d). The study should be formulated to document that we do meet the limits as

described in the comments on "Condition S 1.A, Table 1, Line 11" above. A study to demonstrate 

compliance with the limitations for the 126 priority pollutants in paragraph 40 CFR 423.13(d)(1) " ... 

determined by engineering calculations which demonstrate that the regulated pollutants are not detectable 

in the final discharge by the analytical methods in 40 CFR part 136" is sufficient and appropriate to 

document compliance with the technology based standards. If the Department includes water quality 

based limits in Table 1, we suggest that the language of this section be modified to include something 

like: "This work plan may also address methods to determine that the surface water quality standards 

(WAC 173-201A) are met."

Ecology’s Response

The lab results and reasonable potential analysis showed that the TCG has a reasonable potential to 

exceed the surface water quality and non-detect priority pollutants requirements (Please see table 2 lab 

report, and 3 and 4 reasonable potential analysis, of Appendix C of the fact sheet).

Action Taken: None

Comment 9
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 68 of 70

Fact Sheet, Pages 13, Section I.C -Summary of Compliance It should be noted that 10 of the exceptions 

listed were for groundwater monitoring of the irrigation outfalls. These outfalls were eliminated in a 

permit revision in 2008.

Ecology’s Response

This Summary of Compliance is required to cover the five year permit compliance history (July 2005 

through June 30, 2010). This NPDES permit covered all types of water bodies, including groundwater. 

During the course of the 2005 permit, TCG was land applying wastewater in the summers and TCG 

violated the groundwater quality limits for certain pollutants. That’s what the summary of compliance 

indicates in the permit.

Action Taken: None

Comment 10

Fact Sheet, Pages 13 and 14, Section I.D -Wastewater Characterization Some of the data in Tables 3 and 

4 appear different than what was submitted in the permit application. It is not clear where this information 

came from. It may be appropriate to review and correct this.

Ecology’s Response

Ecology has analyzed not only the permit application data but also five years of monitoring data that TCG 

has submitted to Ecology during the five year permit cycle. 

Action Taken: None

Comment 11

Fact Sheet, Page 20, Section II.D and E -Designated Uses, Evaluation of Surface Water Quality Section 

II.D of the Fact Sheet discusses the designated uses for Hanaford Creek as "Core Summer Salmonid 

Habitat". As noted above, this segment of Hanaford Creek should be listed as "Salmonid Spawning, 

Rearing, and Migration", so these sections should address those parameters in Table 7 and the discussion, 

not the "Core Summer Salmonid Habitat" parameters listed in the Fact Sheet.

Ecology’s Response

The temperature and dissolved oxygen limits in the proposed permit are based on WAC 173-201A which 

currently has the temperature limit set at 16.0 oC and dissolved oxygen at 9.5 mg/L for Hanaford Creek. 

If these temperature and DO limits for Hanaford Creek are revised to 17.5 oC for temperature and 

dissolved oxygen to 8.0 mg/L, these interim limits will be adjusted to reflect this regulation change.

Action Taken: None

Comment 12
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 69 of 70

Fact Sheet, Page 23, Section II.E -Toxic Pollutants Section II.E of the Fact Sheet states in paragraph 2, 

that "40 CFR 423 requires the Permittee must achieve non-detectable levels for the priority pollutants 

(priority pollutant less chromium and zinc) for the cooling tower blowdown discharge ... " This is not a 

correct interpretation of the standard. As stated on page 16 of the Fact Sheet, the standard requires "The 

quantity of pollutants discharged in cooling tower blowdown shall not exceed the quantity determined by 

multiplying the flow of cooling tower blowdown times the concentrations listed below: The 126 priority 

pollutants contained in chemicals added for cooling tower maintenance, no detectable amount, except" 

Chromium, total and Zinc, total. Detectable amounts of naturally occurring pollutants are allowed in the 

discharge as long as those pollutants were not "added for cooling tower maintenance." The Fact Sheet 

should be corrected to address this.

Ecology’s Response

The fact sheet has addressed federal regulations for the cooling tower blowdown industrial process. 

Ecology has used the BAT guidelines for the cooling tower blowdown as the standard for all industrial 

process waste streams for the TCG NPDES permit at this time. In the new proposed permit the cooling 

tower blowdown pollutant limits are applied as interim permit. Ecology will revise and adjust the final 

permit limits based on the completion of the compliance schedule required in the compliance schedule of 

new proposed permit.

Action Taken: None

Comment 13

Fact Sheet, Page 25 and 26, Table 9 Table 9 should be updated to address "Salmonid Spawning, Rearing, 

and Migration" requirements. The table should also be updated to correct the technology based limits for 

priority pollutants described above.

Ecology’s Response

Please see responses to the comments 1 and 12

Action taken: None

.
FACT SHEET FOR NPDES PERMIT WA 0001546

TRANSALTA CENTRALIA GENERATION LLC (TCG)

Page 70 of 70

References

1. EPA Memorandum of June 7, 2010, James A. Hanlon, Director, Office of Waste Management, 

Water Division Directors Regions 1-10, National Pollutant Discharge Elimination System 

(NPDES) Permitting of Wastewater Discharge form Flue Gas Desulfurization (FGD) and Coal 

Residuals (CCR) Impoundments at Steam Electric Power Plant

2. Water Quality Program Guidance, Implementing the State’s Temperature Standards through 

NPDES Permits, July 2010

3. EPA 821-R-09-008, Steam Electric Power Generating Point Source Category: Final Detailed 

Study Report, October 2009

4. Engineering Report, Treatment of Scrubber (Flue Gas Desulfurization System) Blowdown for 

Discharge to the Existing Plant Wastewater Treatment System, Submitted to Washington 

Department of Ecology Water Quality program, by TransAlta Centralia Generation, LLC on 

November 29, 2005

5. Technical Memorandum – TransAlta Centralia – Dewatered Lime Sludge Characterization 

Summary, Submitted to Ecology on February 15, 2005