MEMORANDUM

DATE: A ugust 26

, 201 4

SUBJECT: Revised Development of the Risk and Technology Review (RTR) Emissions

Dataset for the Ferroalloys Production Source Category for the 2014 Supplemental Proposal

FROM: Bradley Nelson, EC/R, Inc.

TO: Phil Mulrine , EPA OAQPS/SPPD/ MMG

1.0 PURPOSE

The purpose of this memorandum is to document the methodologies used to estimate pollutant emissions from processes at two ferroalloy facilities ; Eramet Marietta Inc. (Eramet) and Felman Production (Felman)

. The emission estimates developed in this task were used to create a
database that will be used as input to the risk assessment modeling to estimate the risks due to
emiss ions from these facilities as part of the “risk and technology” (RTR) review for the Ferroalloy Production source category. This analysis supplements the original RTR analysis 1
that supported proposed amendments to the national emission standards for haza rdous air pollutants (NESHAP) for the ferroalloys production source category published in the Federal Register on November 23, 2011 (76 FR 72508).

2.0 BACKGROUND

Under the "technology review" provision of CAA S ection 112, EPA is required to review maximum achievable control technology (MACT) standards and to revise them "as necessary (taking into account developments in practices, processes and control technologies)" no less frequently than every 8 years. Under the "residual risk" provision of the CAA section 112, within 8 years after promulgation of the MACT standards, EPA must evaluate the remaining risks due to emissions of air toxics from the source category and promulgate amendments to the standards if requ ired to provide an ample margin of safety to protect public health or prevent an
adverse environmental effect. EPA has combined the two review activities into the RTR review for the Ferroalloys Production source category.

1 Memorandum from Bradley Nelson, EC/R, Inc. to Conrad Chin, EPA OAQPS/SPPD/MMG

, Draft Development of the RTR Emissions Dataset for the Ferroalloys Production Source Category , October 14, 2011. EPA

- HQ

- OAR

2010

- 0895

- 0040DRAFT FOR INTERNAL REVIEW

2 The MACT standards, for Ferromanganese and Silicomanganese Production appl y to new and existing ferroalloy production facilities that manufacture ferromanganese and /or silicomanganese and are major sources of hazardous air pollutant ( HAP ) emissions or are co

- located at major

sour ces of HAP emissions.

These f erroalloy products are produced using submerged electric arc furnaces, which are furnaces in which the electrodes are submerged into the charge. The submerged arc process is a reduction smelting operation. The reactants co nsist of metallic ores (ferrous oxides, silicon oxides, manganese oxides, etc.) and a carbon

- source reducing agent, usually in the form of coke, charcoal, high

- and low

- volatility coal, or wood chips. Raw materials are crushed and sized, and then conveyed to a mix house for weighing and blending. Conveyors, buckets, skip hoists, or cars transport the processed material to hoppers above the furnace. The mix is gravity

- fed through a feed chute either continuously or intermittently, as needed. At high temp eratures in the reaction zone, the carbon source reacts with metal oxides to form carbon monoxide and to
reduce the ores to base metal. 2 The molten material (product and slag) is tapped from the furnace, sometimes subject to post

- furnace refining, and pou red into casting beds on the furnace
room floor. Once the material hardens, it is transported to product crushing and sizing systems and packaged for transport to the customer.

The NESHAP established emissions standards for the following HAP emission sources at a ferroalloy production facility :

 Submerged arc furnaces

 Metal oxygen refining (MOR) process

 Crushing and screening operations

 Fugitive dust sources.

The current rule contains emission standards that limit particulate matter (PM) emissions fro m existing and new or reconstructed emission sources. The limits for the submerged arc furnaces depend on the product produced and furnace design. The rule also includes limits for the air pollution control devices associated w ith the MOR process and cru shing and screening operations. The current rule sets emission standards for fugitive dust sources by limiting the amount of visible emissions that can be observed from the furnace buildings.

To estimate the facility HAP emissions, a n Information Collection Request (ICR) under Section 114 of the Clean Air Act (CAA) was sent to both ferroalloy production facilities on April 28, 2010 and December 21, 2012 to gather source emission testing data from the furnace s (which

2 EPA

, AP 42, Fifth Edition Compilation of Air Pollutant Emission Factors, Volume 1: Stationary Point and Area Sour ces , Chapter 12.4. Ferroalloy Production. 10/86.DRAFT FOR INTERNAL REVIEW

3 include emissions that occur during charging, smelting , and tapping ) , MOR process and the product crushing process. The HAP source test data that w ere collected from the control device
outlet for each furnace include: metal HAP (arsenic, cadmium, chromium (total and Cr +6 ) , lead,

manganese, mercury, and nickel ) 3 , hydrochloric acid

, hydrofluoric acid, hexavalent chrom ium

, formaldehyde, polycyclic aromatic hydrocarbons (PAH), p olychlorinated b iphenyls (PCB), and

c hlorodibenzodioxin s and chlorodibenzofurans (CDD/CDF) . In addi tion, non

- HAP emissions
were measured from the furnace control device outlet for: particulate matter and carbon
monoxide. The source test data collected for the crushing and sizing operations include: particulate matter, metal HAP (arsenic, total chromium, lead, manganese, mercury, and nickel)

. 4
The source test data collected from the MOR baghouse outlet include: particulate matter, metal HAP (arsenic, total chromium, lead, manganese, mercury, and nickel). 5

3.0 FERROALLOY FACILITY SUMMARY

The following section describes the HAP emission sources for the Eramet and Felman ferroalloy production facilities , which are the two existing facilities in the source category

. Figure 3

- 1 provides a schematic of the smelting, tapping, and casting emission points for a typical ferroalloys production operation.

Eramet Marietta Inc.

The Eramet facility is located in Marietta, Ohio, and ferromanganese (FeMn) and silicomanganese (S iMn) are produced using two furnaces identified as Furnace 1 and Furnace
12.

Furnace 1 is a submerged arc furnace rated at 30 megawatts (MW) and is equipped with a negative pressure fabric filter to control particulate emissions and metal HAP. The fabr ic filter controls emissions from the furnace smelting operation and was installed in 2011 to replace a wet scrubber system. A separate fabric filter system identified as Furnace 1 Tapping Baghouse is used to control captured fugitive emissions from the t apping process from this furnace. The casting process associated with this furnace is uncontrolled.

3 Total phosphorus was measured for the ICR using EPA Method 29; however this method does not distinguish between white phosphorus (which is a non

- HAP) and red phosphorus (which is a HAP). Due to the uncert ainty of the percentage of red phosphorus in the total phosphorus test results, it was concluded that phosphorus would not be incorporated in the emissions used for modeling.

4 T otal phosphorus was measured using Method 29 and therefore not included in th e emissions used for modeling

. 5 Again, total phosphorus was measured using Method 29 and therefore not included in the emissions used for modeling

.Figure 3

- 1. Diagram of the Ferroalloys Process and Emission PointsFurnace 12 is a submerged arc furnace rated at 22 MW and is equipped with two wet scrubbers

to control emissions from the furnace smelting operation and captured fugitive emissions from the tapping process. The scrubbers operate simultaneously and exhaust through a single stack. The casting process associated with this furnace is uncontrolled.

The facilit y has a third furnace, Furnace 1 8, which is permitted, but is considered to be inoperable until extensive repair is made to the furnace. Theref ore, Furnace 18 was not considered an emission source and was not included in the emission inventory for Eramet for
actual emissions

. However, an estimate of Furnace 18 emissions was included for the calculation
of MACT “allowable” emissions. Other HAP em ission sources include the MOR process controlled by a positive

- pressure baghouse which also controls fugitive emissions captured from casting of the product from MOR and a crushing a nd sizing system (C2P) that is controlled by
three negative pressure baghouse s . There are also fugitive emissions that are emitted from each of these emission sources, in addition to the fugitive emissions from the casting operations for Furnace 1, Furnace 12, and the MOR process

.

The emission sources used for modeling emissions from the Eramet facility were developed
based on the plant configuration discussed above and data and information collected through the
ICRs . For the furnace s, emission points were developed for the control device outlet emissi ons and for fugitive emissions from the furnace smelting and furnace tapping

. For the MOR process ,

e mission points were developed for the MOR baghouse outlet and for fugitive emissions from the MOR process

. For the crushing system, emission points were developed for each of the three baghouse outlets and one emission point for fugitive emissions from the crushing operation. Emission points were also developed for fugitive emissions from casting operations associated
with each of the two furnaces and for the MOR process.

Felman Production Inc.

The Felman facility is located in New Haven, West Virginia and produces SiMn using three
furnaces identified as Furnace 2, Furnace 5, and Furnace 7. Furnaces 2, 5, and 7 are open submerged arc furnaces rated at 32, 20, and 20 MW respectively. Each of these furnaces is equipped with a positive

- pressure baghouse to control emissions of PM and metal HAP from the
furnace. The baghouse from each furnace also controls the captured fugitive emissions from the

assoc iated furnace tapping and casting processes.

The facility has a crushing and sizing system controlled using a negative pressure baghouse. There are also fugitive emissions that are emitted from each of these emissions sources, in addition to the fugitive emissions from the casting operations for Furnace 2, Furnace 5, and

Furnace 7.DRAFT FOR INTERNAL REVIEW

6 The Felman facility emission points used for modeling emissions were developed from the plant configuration discussed above and data and information collected through the ICR

. Emission points were developed for the control device outlet s for each of the three furnace s, as well as fugitive emission point s for smelting and tapping at each of the three furnace s. For the crushing
system s , emission points were developed for the crusher baghouse outlet and fugitive emissions
from the crushing units . Emission points were also developed for casting fugitive emissions
from each of the three furnace s.

4 .0 POINT SOURCE POLLUTANT E MISSION DATA

The following section describes the test data that w ere collected from emission point sources at each of the ferroalloy facilities. This section will describe the test methods that were used to measure emissions for each pollutant from the processes that were tested. A summary of the type of pollutant data collected in the ICR s is presented in Table 4

- 1. More information on the
test data collected in the ICR can be found in the test data review summaries 6

, 7 located in the
docket.

These test report reviews provide a description of how the test data were analyzed and compiled, and provides a comparison of the reported test results with the calculated results used to estimate the modeling emissions. The individual test reports submit ted by the facilities can also be found
in the docket.

Some of the analytical r esults for the HAP pollutants were reported below the detection limit. For these test results, one half of the detection limit was used to estimate the emission rate of the HAP pollutant. The use of one half of the detection limit for calculating emission rates from analytical data results reported below the detection limit is based on EPA’s revised procedures 8
for developing emission factors.

6 Memorandum from Bradley Nelson, EC/R to Conrad Chin, EPA/OAQPS/SPPD/MMG

, Ferroalloys 2012 Test Report Review

, May 28, 2013

. 7 Memorandum from Bradley Nelson, EC/R to Conrad Chin, EPA/OAQPS/SPPD/MMG

, Ferroalloys 201 3 Test Report Review , July 29 , 2013

. 8 Recommended Procedures for Development of Emissions Factors and Use of the WebFIRE Emissions Factor Datab ase, Revised Draft Report, December 17, 2010

. http://www.epa.gov/ttn/chief/efpac/procedures/procedures_draft122010.pdfDRAFT FOR INTERNAL REVIEW

7 Table 4

- 1. Summ ary of HAP Emissions Data Collected in the ICR s

Facility Process Particulate Matter Metal HAP Mercury Cr+6 HCl/ HF Form

aldehyde PAH, PCB, CDD/CDF

Method

5D a Method 5 Method 29 Method
29/30B SW Method

0061 Method 26A Method 316 Method
23/0010 CARB

428/429

Felman Furnace       

Crusher   

Eramet Furnace        

MOR   

Crusher   

a The furnaces at Felman are each equipped with positive pressure baghouse and therefore Method 5D was used to measure PM emissions from these emission sources. All other emission sources are equipped with either a negative pressure baghouse or ve nturi

scru bber and were measured using Method 5.DRAFT FOR INTERNAL REVIEW

8 Particulate Matter

Test data for PM were received from both ferroalloy facilities for each furnace and for one product crushing operation. Eramet provided PM results from the Furnace 12 scrubber outlet, the Furnace 1 baghouse outlet, the Furnace 1 tapping baghouse outlet, t he MOR process baghouse outlet, and from the crushing and sizing operation baghouses (C2P Crushing/Sizing Baghouse #1) using EPA Method 5. Felman provided PM test results from the Furnace 2 baghouse outlet, the Furnace 5 baghouse outlet, the Furnace 7 bag house outlet using EPA Method 5D, and the baghouse outlet from the crushing and sizing operation using EPA Method 5.

Metal HAP

Test data for metal HAP (arsenic, cadmium, chromium, lead, manganese, mercury, and nickel) were
collected from the Furnace 12 scrubber outlet, the Furnace 1 baghouse outlet, the Furnace 1 tapping baghouse outlet, and from Baghouse #1 from the product crushing operation at Eramet. The metal HAP data for Felman were obtained from the Furnace 2 baghouse outlet, the Furnace 5 bagho use outlet, and the baghouse controlling emissions from the crushing and sizing operation. The furnace and product crushing test data from both facilities were collected using EPA Method 29 for arsenic (As), cadmium (Cd), total chromium (Cr), lead (Pb), m anganese (Mn), total mercury (Hg), and nickel (Ni). Additional mercury test data were collected for both facilities using EPA Method 30B. The EPA Method 29 analytical results were corrected using the reported field blank 9 results from the analytical test report.

Hexavalent Chromium

Hexavalent chromium (Cr +6 ) test data were collected from Furnace 2 and Furnace 12 for the Felman and Eramet facilities respectively, using EPA SW Method 0061 . No hexavalent chromium data were requested for the product crus hing operations. Hexavalent chromium emissions were estimated for the furnaces that were not tested and the product crushing operations by using the hexavalent chromium/PM ratio from the tested sources. A discussion of this calculation is provided
in Sec tion 5.0.

Hydrochloric Acid/Hydrofluoric Acid

Test data for hydrochloric acid (HCl) and hydrofluoric acid (HF) were collected from the Furnace 12 scrubber outlet, and the Furnace 1 baghouse outlet at Eramet. Test data for HCl was also collected for the Furnace 1 tapping baghouse at Eramet. Test data f or HCl and HF were collected

9 The primary purpose of field blanks is to trac e sources of artificially introduced contamination. The f ield b lank results include total ambient conditions during sampling and laboratory sources of contamination.DRAFT FOR INTERNAL REVIEW

9 for the Furnace 2 baghouse outlet at Felman. In addition, HCl data was collected for the Furnace 5 and Furnace 7 baghouse outlets at Felman. The HCl and HF data for both facilities were collected using EPA Method 26A. The pr oduct crushing processes at both facilities were not tested for HCl or HF, because it believed that these are non

- combustion processes and thus do not emit these HAP pollutants.

The test data for HCl is a mixture of detected and non

- detected analytical re sults. There were a total of 29 runs that reported non

- detect analytical results out of the total of 45 test runs for HCl. For the analytical results that were reported as non

- detect, one half of the detection limit was used
to estimate the HCl concentra tion for the test runs. For HF, all of the test results were reported as

non

- detect, and again, one half of the detection limit was used to estimate the HF concentration for
the test runs. While we calculated numerical estimates for HF based on the assump tion that non

detects were equal to 1⁄2 detection limit and included these estimates in the inputs to our risk model, we have no evidence that HF is emitted from these sources. Therefore, for purposes of our estimates of emissions and associated risks, we ar e assuming that HF is not emitted from these sources.

Formald e hyde

Testing for formaldehyde was performed on the Furnace 12 scrubber outlet, the Furnace 1 baghouse outlet, and the Furnace 1 tapping baghouse outlet at Eramet, and the Furnace 2 baghouse ou tlet, Furnace 5 baghouse outlet, and Furnace 7 baghouse outlet at Felman. All of the formaldehyde test data was collected using EPA Method 316. Formaldehyde testing was not performed on any of the product crushing processes, because it believed that these are non

- combustion processes and thus do not emit these HAP pollutants.

The test data for formaldehyde reported 6 runs below the detection limit out of a total of 18 test

runs. The emissions rates for the detected formaldehyde runs ranged from 0.01 to 0.26 pounds per hour with an average and median of 0.07 and 0.05 pounds per hour , respectively

. For the analytical results that were reported as non

- detect, one half of the detecti on limit was used to estimate the formaldehyde concentration for the test runs.

PAH/PCB/

CDD/CDF

Test data for polychlorinated biphenyls (PCB), c hlorinated dibenzo

- p

- dioxins (CDD), and
chlorinated dibenzo

- p

- furans (CDF) were collected at the Furnace 12 s crubber outlet, Furnace 1 baghouse outlet, and the Furnace 1 tapping baghouse outlet at Eramet. The test methods used to collect the samples were EPA Method 23, Method 0010, California Air Resources Board (CARB)
Method 428 and CARB 429. Test data were co llected for PAH, PCB, and CDD/CDF data for the Furnace 2 baghouse outlet and the Furnace 5 baghouse outlet at Felman using CARB methods 428 and 429. Test data for PAH were collected at the Furnace 7 baghouse outlet at Felman using
CARB method 429. No PAH , PCB, or CDD/CDF emissions data were collected for the productDRAFT FOR INTERNAL REVIEW

10 crushing units, because these are non

- combustion processes and thus do not emit these HAP pollutants.

The analytical results for CDD/CDF reported 230 of the individual compounds were below the
detection limit out of a total of 306 reported individual compound s. For the individual CDD/CDF compounds that were detected, the emissions ranged from 1.8 x 10 - 10 to 7.3 x 10 - 8 pounds per hour with an average and median of 6.5 x 10 - 8 and 3.5 x 10 - 9 pounds per hour, respectively. For PCBs,
107 out of 207 reported individual compounds were reported below the detection limit. The
emissions from these detected individual PCB compounds ranged from 7.0 x 10 - 10 to 7.5 x 10 - 6
pounds per hour with an average and median of 5.8 x 10 - 7 and 4.6 x 10 - 8 pounds per hour, respectively. For PAHs, 1 8 out of 513 individual compounds analytical results were reported below
the detection limit. For the individual PAH compounds that were detected, the emission value s ranged from 1. 9 x 10 - 6 to 1.9 x 10 - 1 pounds per hour with an average and median of 7.6 x 10 - 3 and

1 .5 x 10 - 3 pounds per hour, respectively. For the test results that were reported below the detection limit, one half of the detection limit was used to calculate the concentration and emission rate for the purposes of estimating emissions for the risk assessment modeling

.

Other Data

In addition to the pollutant data described above, analyses of the coal/coke and furnace exhaust concentrations of oxygen (O 2 ), carbon dioxide (CO 2 ), and carbon monoxide (CO) were measured.
The O 2 and CO 2 concentrations were measured using EPA Method 3A, and the CO concentration was measured using EPA Method 10. For coal/coke, the samples were analy zed using ASTM
D3177

- 02 for sulfur, D3172

- 07 for proximate analysis, and D3176

- 09 for ultimate analysis. Visible emission data from the furnace building using EPA Method 9 were also provided in the test reports. These visible emission reports provide opa city readings from the furnace buildings for furnace smelting and tapping operations during the furnace control device outlet tests

.

5 .0 METHODOLOGY FOR DEVELOPING EMISSION ESTIMATES

The test data provided in the ICR response s w ere used to develop a mode ling emissions database
for estimating the risks associated with the HAP emissions from the ferroalloy production facilities. The analytical results provided in the ICR response s were used to calculate emissions for each of the pollutants. This section describes the methodology used to estimate annual emissions from all of the sources at each of the ferroalloy facilities. A summary of the estimated annual HAP
emissions is provided at the end of this section.

Some of the pollutant emission s were based on one or more analytical results that were reported below the detection limit. For these analytical results, one half of the detection limit was used to estimate the pollutant concentration

. For some HAP (e.g., dioxins, furans, PCBs), the m ajority ofDRAFT FOR INTERNAL REVIEW

11 the test results were below detection limit. For HF, all the results were below detection. Nevertheless, to be conservative (i.e., overestimat ing rather than underestimat ing emissions and risks), we developed estimated emissions for these HAP using the method described above.

5.1 F urnace Smelting Emissions

The furnace annual emissions for all pollutants were estimated using the information provided in the facility’s ICR test reports . The annual emissions for the tested furnace units were calculated using stack gas parameters and analytical results provided in the submitted test reports and

convert ed to annual emissions assuming the furnaces operate 24 hours per day for 365 days per year (i.e., 8

, 760 hours of operation per year )

. We have PM test results for all stack emissions points. For some of the other pollutants, we only have data for a subset of emissions points. For those pollutants that were not tested for a specif i c emissions point , the annual emissions were estimated
b y multiplying the PM emissions rate by the pollutant

- to

- PM ratio from a comparable emission

source. A more detailed description for each facility is provided in the paragraphs below.

Eramet

The Eramet facility provided ICR test data for all pollutants for the Furnace 12 scrubber outlet and the Furnace 1 baghouse outlet with the exception of Cr +6

, which was not tested at the Furnace 1 baghouse outlet

. Eramet also provided test data from the Furnace 1 and 12 smelting baghouse outlets and the Furnace 1 tapping baghouse outlet during production of FeMn and SiMn.

The main source of manganese ( Mn ) and mercury ( Hg ) emissions from the furnace smelting

process is the manganese ore used by Eramet to produce the ferroalloys product , which may contain Hg as an impurity

. The amount of Mn ore used to produce a ton of FeMn is greater than the
amount of Mn ore used to produce a ton of SiMn. Therefore, Mn and Hg emissions are higher during the production of FeMn than during the production of SiMn. The other HAP pollutant
emissions were assumed to be equivalent during the production of either FeMn or SiMn.

To estimate the annual Mn and Hg emissions for these emission sources, it was assumed that FeMn
and SiMn were produced equ ally during the year by each furnace ( e.g., 4,380 hours per year producing SiMn and 4,380 hours per year producing FeMn). This assumption was based on
conversations with Eramet on the historical production of the FeMn and SiMn products at their facility

. The annual emissions were calculated by averaging the emissions during the production of each product and multiplying that average value by the number of production hours. The FeMn and
SiMn totals were then added to calculate the annual emissions. T he equation for estimating the
f urnace smelting baghouse outlet and the furnace tapping baghouse M n emissions is provided
below.DRAFT FOR INTERNAL REVIEW

12 where;

M n Annual = Annual M n emissions from furnace smelting baghouse ou tlet or the tapping baghouse
outlet when producing FeMn and SiMn

, M n SiMn = Average M n test results when producing SiMn in pounds per hour

, M n FeMn = Average M n test results when producing FeMn in pounds per hour

, 4,380 hours per year.

The same equation is used to estimate the annual Hg emissions using the average Hg test results for FeMn and SiMn production. The formula is as follows;

where;

Hg Annual = Annual Hg emissions from furnace smelting baghouse outlet or the tapping baghouse outlet when producing FeMn and SiMn, Hg SiMn = Average Hg test results when producing SiMn in pounds per hour

, Hg FeMn = Average Hg test results when producing FeMn in pound s per hour

, 4,380 hours per year.

To estimate the Cr +6 emissions from the Furnace 1 baghouse outlet , the Furnace 1 baghouse outlet PM emission rate was multiplied by the Furnace 12 scrubber outlet Cr +6

- to

- PM ratio. The equation
for the Cr +6 emissions estimation for the Furnace 1 baghouse outlet are shown below: ( )

where;

Cr +6 Furnace 1 = Estimated C r +6 emissions from EAF 1 in tons per year,

PM F urnace 1 = PM test results for the Furnace 1 baghouse outlet in tons per year,
Cr +6 F urnace 12 = Cr +6 test results from the Furnace 12 scrubber outlet in tons per year, and

PM F urnace 12 = PM test results from the Furnace 12 scrubber outlet in tons per year.

FelmanDRAFT FOR INTERNAL REVIEW

13 The Felman facility submitted several test reports for Furnaces 2, 5, and 7 that provided pollutant
test data . The test reports for Furnace 2 provided test data for PM, metal HAP, Cr +6 , HCl, HF, formaldehyde, PAH, CDD/CDF, and PCB. The test reports for Furnace 5 provided test data for PM, metal HAP, HCl, formaldehyde, PAH, CDD/CDF, and PCB. The test reports for Furnace 7 provided test data for PM, metal HAP, HCl, formaldehyde, and PAH. The Cr +6 and HF emissions
for Furnaces 5 and 7 were estimated using the pollutant

- to

- PM ratio from Furnace 2 using the same estimation approach used for Eramet , as described above. The CDD/CDF and PCB emissions from Furnace 7 were assumed to be the same as the reported emissions from Furnace 5. This assumption is based on the fact that both Furnace 5 and Furnace 7 are the same size and produc e the same product.

5.2 Furnace Smelting Fugitive Emissions

At the top of the furnaces there is hooding that captures the vast majority of the emissions comin g out of the top of the furnace smelting operation and these emissions are vented to a control device (either a baghouse or scrubber). Therefore, we have developed estimates of the fugitive emissions from the top of these furnaces. As shown in table 5

- 2, we estimate that about 98% of these emissions are captured and directed to a control device. This estimate is based on observations of the furnace smelting process and hood system. However, it is not a closed system and we believe there are some fugitiv e emissions coming from this source.

We have not identified any emissions factors based on the direct measurement of fugitive emissions from ferroalloys production furnaces to estimate these emissions. Therefore, we use d a mass balance approach to estima te these emissions. The specific method is described in the following paragraphs.

The furnace smelting fugitive emissions were estimated by calculating the uncontrolled PM emissions from the furnace and estimating the percentage of the uncontrolled PM emissions that are captured from the furnace . The difference between the uncontrolled pollutant emission s and the estimated captured pollutant emissions were assumed to be the furnace fugitive emissions. The
uncontrolled PM pollutant emissions w ere calcu lated using the furnace annual emissions for PM
and the estimated control efficiency. A summary of the assumed fabric filter and scrubber control efficiencies for the pollutants is presented in Table 5

- 1 . These control efficiencies are based on expected control efficiencies found on the EPA Clean Air Technology Center website

. 10 A summary of the assumed process fugitive capture efficiencies is provided in Table 5

- 2. These capture efficiencies are based on visual observations of the fugitive capture durin g process operations. It was also assumed that 92 percent of the furnace control device emissions are generated from the furnace and 8 percent of the furnace control device emissions are generated

10 EPA Technology Transfer Network

, Clean Air Technology Center

, General Information on CAT C Products

, http://www.epa.gov/ttncatc1/products.htmlDRAFT FOR INTERNAL REVIEW

14 Table 5

- 1

. Assumed Control Device Efficiencies used to Estimate Furnace Fugitive Emissions

Pollutant(s) Scrubber Control Efficiency (%) Fabric Filter

Control Efficiency (%)

Particulate Matter 90 98

Metal HAP 90 98

Hexavalent Chromium 90 98

Mercury 15 15
Hydrochloric Acid/Hydrofluoric Acid 90 0
Formaldehyde 90 0

PAH, PCB, CDD/CDF 50 50

Table 5

- 2

. Assumed Baseline C apture Efficiencies used to

Estimate Process Fugitive Emissions

Pollutant(s) Assumed Fugitive Capture Efficiency (%)

Eramet
Furnace 1 and 12 Smelting 98

Furnace 1 Tapping 20
Furnace 12 Tapping 30

MOR Process 40
Furnace 1 and 12 Casting 0
MOR Casting 40
Crushing and Sizing 95

Felman
Furnace 2, 5, & 7 Smelting 98
Furnace 2, 5, & 7 Tapping 70
Furnace 2, 5, & 7 Casting 40
Crushing and Sizing 85DRAFT FOR INTERNAL REVIEW

15 during tapping of the furnace

. These assumptions are based on engineering judgment of the furnace operations and the tapping fugitive capture systems

. The equation used to estimate fugitive PM
emissions from the furnace smelting process is shown below;

[ ( ) ( ) ( ) ] [ ( ) ( ) ]

where;

P M smelt = Estimated fugitive PM emissions from the furnace in tons per year,

P M out = Control device outlet PM emissions in tons per year, CE = Control efficiency of the furnace control device, 0.92 = Percentage of uncontrolled emissions generated from the furnace

, and Capt smelt = Estimated capture efficiency of the furnace smelting operations

.

Other furnace smelting fugitive HAP pollutants from the furnace smelting operation were calculated by multiplying the calculated PM furnace smelting fugitive emissions value by the HAP pollutant

- to

- PM ratio for the associated furnace. The HAP pollutants that were estimated from the
furnace smelting process include; metal HAP ( e.g., Mn, As, Cd, Cr, Ni, Pb) , Cr +6 , HCl, HF, formaldehyde, PAH, CDD/CDF, and PCB. The equation for estimating these fugitive HAP pollutants from the furnace smelting process is shown below; ( )

where;

HAP smelt = Estimated fugitive HAP emissions from furnace smelting in tons per year,

PM smelt = Estimated fugitive PM emissions from furnace smelting in tons per year,

HAP out = Reported outlet HAP emissions from the associated furnace in tons per year, and

P M out = Reported outlet PM emissions from the associated furnace in tons per year.

This approach was used to calculate metal HAP (e.g., Mn, As, Cd, Cr, Ni, Pb), Cr +6 , HCl, HF, formaldehyde, PAH, CDD/CDF, and PCB fugitive emissions from the furnace smelting operation
for each of the furnaces at Eramet and Felman.

The fugitive emissions for mercury were calculated using a different methodology because of the large difference in control efficiency between PM and mercury. As shown in Table 5

- 1, the control efficiency for PM using a fabric filter is 98 percent (90 percent with a scrubber), whereas the control efficiency for mercury using either the fabric filter or scrubber is 15 percent. The lower control efficiency for mercury is based on the assumption th at 80 percent of the total mercury emissions from the furnace smelting process are gaseous elemental mercury and 20 percent areDRAFT FOR INTERNAL REVIEW

16 gaseous mercuric chloride. 11 The furnace control devices can effectively control particulate mercury (e.g., mercuric chloride) f rom the exhaust stream, but little or no control of gaseous elemental mercury emissions or gaseous mercuric chloride

.

Therefore , to account for the difference in control efficiency

, an equation using the different control efficiencies for PM and mercury were substituted into the equation for calculating HAP fugitive
emissions from s me l ting process above. The equation used to estimate fugitive mercury emissions
from the furnace smelting process is provided below ;

( ) ( ) ( )

where;

CE PM = Control efficiency of PM for the control device (98%),
CE Hg = Control efficiency of mercury for the control device (15%), Hg smelt = Estima ted fugitive mercury emissions from furnace smelting in tons per year,

PM smelt = Estimated fugitive PM emissions from furnace smelting in tons per year, Hg out = Reported outlet HAP emissions from the associated furnace in tons per year, and

PM out = Reporte d outlet PM emissions from the associated furnace in tons per year.

5.3 Furnace Tapping Fugitive Emissions

The furnaces at these facilities are typically tapped several times per day from the lower section of the furnace. This process results in signifi cant fugitive emissions. The percent capture of tapping fugitive emissions varies significantly across furnaces. As shown in table 5

- 2, we estimate that the range is about 20% to 70% capture. This variability relates to the design of the tapping system (e.g., use of cascading tapping ladles vs. single ladles), tapping hood design and capacity of the air handling system.

We evaluated available emissions factors (EFs) that could be used to estimate these emissions. We did not identify reliable factors t hat were specific to this industry. However, we found EFs from the steel industry, from a similar process, that we believe are appropriate to use to estimate emissions for tapping from Ferroalloys furnaces. After searching for, and reviewing, available e missions factors, we determined that AP

- 42 EF for Basic Oxygen Furnace (BOF) tapping were the best available EFs to use. Therefore, the furnace tapping fugitive PM emissions for the Eramet and Felman facilities were estimated using an AP

- 42 emission facto r (EF) for Basic Oxygen Furnace (BOF) tapping 12 . The AP

- 42 documentation for BOF tapping fugitives lists two types of EFs

11 EPA, Technology Transfer Network Clearinghouse for Inventories & Emissions Factors Speciate Version 4.3, September 2011.

12 AP

- 42, Compilation of Air Pollutant Emission Factors, Chapter 12.5 Iron and Steel Production, October 1986. http://www.epa.gov/ttn/chief/ap42/ch12/final/c12s05.pdf (see Table 12.5

- 1)DRAFT FOR INTERNAL REVIEW

17 available to estimate these emissions; one measured at the source (which is 0.92 pound PM per ton of product) and one measured at the building monitor (which is 0.29 pound PM per ton of product). After reviewing these EFs, we determined that the BOF tapping building monitor EF was not based on measurements at the building monitor, but on measurements taken in the primary hood using an
i n

- stack filter . The EF incorporates a capture efficiency of 93 percent which was assumed to estimate the building monitor EF. The BOF tapping at source EF was conducted in the hood duct leading to the wet scrubber. Based on this information, the BOF tapping at source EF was determined to be more appropriate and was chosen to estimate the fugitive emissions from tapping from the ferroalloy furnaces.

As mentioned above, t he EF for BOF tapping at source is listed as 0.92 pound of PM per ton of product produced (lb/Ton). However, after reviewing the source of the EF , it was determined that
the test data used to determine the EF was based on an estimated capture of 70% of the total emissions (with 30 percent escaping t o the building) . Therefore, t o estimate the total PM emissions from BOF tapping, the EF of 0.92 lb/Ton was divided by 70 percent to obtain the total PM EF of
1.3 lb/Ton. This EF and the following equation were used to estimate fugitive PM emissions from tapping of the furnaces at Eramet and Felman.

( ) ( )

where;

PM t ap = Estimated fugitive PM emissions from tapping in tons per year,
1.3 = PM fugitive EF for BOF tapping in pounds per ton of steel produced, P = Reported production of product for the associated furnace in tons per hour, and Capt t ap = Estimated capture efficiency of the furnace tapping operations (see Table 5

- 2)

, 8760 = Hours of operation per year, 2000 = Pounds per ton.

The emissions of metal HAP (e.g., Mn, As, Cd, Cr, Ni, and Pb ) , Cr +6 , HCl, and HF from the furnace tapping process w ere estimated using the HAP

- to

- PM ratio from the respective furnace outlet emissions. The equation for estimating these fugitive HAP emissions is provided below ; ( )

where;

HAP t ap = Estimated fugitive HAP (e.g., Mn, Ni, Pb, As) e missions from tapping in tons per year,

PM t ap = Estimated fugitive PM emissions from tapping in tons per year,DRAFT FOR INTERNAL REVIEW

18 HAP out = Reported outlet HAP (e.g., Mn, Ni, Pb, As) emissions from the associated furnace in tons per year, and

PM out = Reported outlet PM emissions from the associated furnace in tons per year.

The majority of Hg, PCB, PAH, CDD/CDF and formaldehyde emissions are assumed to come from the furnace smelting operation , due to the volatility of these HAP and the heat generated in the smelting process. The emissions test results from the Furnace 1 tapping baghouse compared to the test results from the primary furnace 1 stack confirms t hat this is the case. For example, the measured mercury emissions were about 1 5 ,000 times higher from the furnace 1 primary baghouse compared to the tapping baghouse. This shows that the vast majority of mercury emissions are emitted through the stacks a nd not as fugitives. However, emissions of these HAP were measured in the Furnace 1 tapping baghouse at Eramet (emissions were not zero) , and therefore are assumed
to be emitted to some degree as fugitives during the furnace tapping process. To estimate these fugitive emissions, an EF was developed using the available test data from the Furnace 1 tapping baghouse for each of these pollutants. For mercury, the EF was developed using the PM and Hg
emission result from the Furnace 1 tapping baghouse at Eramet and the tapping PM EF used to calculate the fugitive PM emissions from tapping. The equation for calculating the Hg EF is as follows;

( ) ( )

where;

FeMn EF Hg tap = Hg fugitive EF from fu rnace tapping in pounds per ton of FeMn produced

, 1.3 = PM fugitive EF for BOF tapping in pounds per ton of steel produced,
0.0000526 = Reported outlet H g emissions from the Furnace 1 tapping baghouse in tons per year,
and
2.34 = Reported outlet PM emissio ns from the Furnace 1 tapping baghouse in tons per year.

This calculation provide s a n Hg ta p ping fugitive EF of 2.91 x 10 - 5 pounds per ton of FeMn produced. The Hg emission rate was calculated using 2013 test data from the Furnace 1 tapping baghouse and the PM emissions rate was calculated using 2011, 2012 13 and 2013 14 test data from the Furnace 1 tapping baghouse. T h e reported test results are based on the production of FeMn, which produces higher Hg emissions rates in comparison to SiMn production. Becau se there was no Hg test data from the Furnace 1 tapping baghouse during SiMn production, an Hg EF was developed for SiMn production using the calculated FeMn Hg emissions factor and applying a ratio

13 Memorandum from Bradley Nelson, EC/R to Conrad Chin, EPA/OAQPS/SPPD/MMG

, Ferroalloys 2012 Test Report Review

, May 28, 2013

. 14 Memorandum from Bradley Nelson, EC/R to Conrad Chin, EPA/OAQPS/SPPD/MMG

, Ferroalloys 201 3 Test Report Review , July 29 , 2013

.DRAFT FOR INTERNAL REVIEW

19 of the Furnace 1 baghouse outlet Hg emissions for SiMn an d FeMn production. The equation for calculating the Hg EF for SiMn production is as follows;

( ) ( )

where;

SiMn EF Hg tap = Hg fugitive EF from furnace tapping in pounds per ton of SiMn produced,
2.91 x 10 - 5 = Hg fugitive EF from furnace tapping in pounds per ton of FeMn produced,
0.00 678 = Reported outlet Hg emissions from the Furnace 1 baghouse outlet during SiMn production in pounds per year, and
0.0288 = Reported outlet Hg emissions from the Furnace 1 bag house outlet during FeMn production in pounds per year

.

This calculation provides an Hg tapping fugitive EF of 6.85 x 10 - 6 pounds per ton of SiMn produced. The SiMn Hg EF was used to estimate Hg fugitive emissions from the tapping process for Furnaces 2, 5, and 7 at Felman , which produce only SiMn

. This factor may overestimate the mercury emissions from Felman, because Felman uses a lower mercury content manganese ore in comparison to the manganese ore used by Eramet. However, since there is no specific test data
from the tapping process at Felman , it is believed that this SiMn Hg emissions factor will provide a conservative estimate of fugitive Hg emissions from tapping. For Eramet, an average of the FeMn and the SiMn Hg EF s (1.80 x 10 - 5 pounds per ton of FeMn/SiMn produced ) was used to estimate Hg fugitive emissions from the tapping process. An average was used because of the assumption (as described in Section 5.1) of 50 percent annual SiMn production and 50 percent annual FeMn production for both Furnace s 1 and 12 at Eramet. Th ese EF s and the following equation were used to estimate fugitive Hg emissions from tapping of the furnaces at Eramet and Felman.

( ) ( )

where;

Hg tap = Estimated fugitive Hg emissions from tapping in tons per year,

EF Hg tap = Hg fugitive EF for tapping in pounds per ton of product (SiMn or SiMn/FeMn), P = Reported production of product for the associated furnace in tons per hour, and Capt tap = Estimate d capture efficiency of the furnace tapping operations, 8760 = Hours of operation per year, 2000 = Pounds per ton.

The estimated capture efficiency of the tapping operations for each of the furnaces are provided in
Table 5

- 2.DRAFT FOR INTERNAL REVIEW

20 The PCB, PAH, CDD/CDF and f ormaldehyde fugitive emissions from the tapping process were calculated using the same methodology used to estimate fugitive Hg emissions. An EF was developed for each of the organic HAP compounds using the test data from the Furnace 1 tapping baghouse. It was assumed for this analysis that there is no variation of fugitive organic HAP fugitive emissions based on product (e.g., SiMn or FeMn produ ction). As an example, the equation for calculating the naphthalene EF is as follows;

( ) ( )

where;

EF Naphthalene tap = Naphthalene fugitive EF from furnace tapping in pounds per ton of FeMn or SiMn produc ed, 1.3 = PM fugitive EF for BOF tapping in pounds per ton of steel produced,
1.34 x 10 - 2 = Reported outlet naphthalene emissions from the Furnace 1 tapping baghouse in tons per year, and 2.34 = Reported outlet PM emissions from the Furnace 1 tapping baghouse in tons per year.

This calculation provides a naphthalene tap p ing fugitive EF of 7.42 x 10 - 3 pounds per ton of FeMn or SiMn produced

. This methodology was used to estimate the fugitive organic HAP emissions factor for each of the organic HAP com pounds

. A table of the organic HAP fugitive EF s for the tapping process is provided in Table 5

- 3. Th ese EF s and the following equation were used to estimate fugitive organic HAP emissions from tapping of the furnaces at Eramet and Felman. An example of the naphthalene fugitive emission calculation is provided below;

( ) ( )

where;

Naphthalene tap = Estimated fugitive naphthalene emissions from tapping in tons per year,
EF Naphthalene tap = Naphthalene fugitive EF for tapping in pounds per ton of product (SiMn or SiMn/FeMn), P = Reported production of product for the associated furnace in tons per hour, and Capt tap = Estimated capture efficiency of the furna ce tapping operations, 8760 = Hours of operation per year, 2000 = Pounds per ton.

The estimated capture efficienc ies of the tapping operations for each furnace are provided in Table 5

- 2.DRAFT FOR INTERNAL REVIEW

21 5.4 Casting/MOR Fugitive Emissions

We also evaluated available emissions factors that could be used to estimate casting and MOR fugitive emissions. We identified one EF for casting specific to this industry from Ohio EPA of 2.4

lb/ton

. However, we could not find any documentation to suppo rt this emissions factor, so we determined it was not appropriate to use it. We did not find any other EFs specific to this industry. However, we did identify EFs from the Steel industry from AP

- 42 for a similar source known as hot
metal transfer

. 15 Simi lar to the tapping EFs, we identified two EFs (one “at the monitor” and one “at the source”). The “hot metal transfer at monitor” EF is 0.056 lb/ton and the EF for the “hot metal transfer at source” is 0.19 lb/ton. However, we evaluated these EFs further and concluded
there was no actual test at the “monitor”. Furthermore the 0.056 lb/ton test assumed 100% capture (the test was conducted using an in

- stack filter). Therefore, we determined it was not appropriate to use the “at monitor” EF. The only rema ining available EF that seemed valid was the 0.19 lb/ton EF. Thus, after searching for, and reviewing available emissions factors, we concluded the best
available EF to use to estimate these emissions was the 0.19 lb/ton EF.

The MOR process involves the top lance injection of oxygen to reduce the carbon content and increase the manganese content of the molten FeMn product. The majority of the fugitive emissions from this process occur during the transfer of the molten metal from the tapping vessel to
the MOR vessel, and during the waiting period for the MOR vessel to become free. Other fugitive emissions from this source occur during the injection of oxygen

. H owever this process is well
controlled and is not expected to be a significant source of fugitiv e emissions. Since the majority of fugitive emissions from MOR occur during pouring and waiting, it was assumed that the ‘hot metal transfer at source” EF of 0.19 lb/ton would be appropriate for estimating fugitive emission from the

MOR.

Therefore, parti culate matter emissions from casting and the MOR process were estimated using an

AP

- 42 PM EF for hot metal transfer (at source) of 0.19 pounds of fugitive PM emissions per ton of hot metal. This EF was used to estimate the fugitive PM emissions from casti ng and MOR operations. This EF and the following equation were used to estimate fugitive PM emissions from product casting at Eramet and Felman and the MOR process at Eramet.

( ) ( ) where;

PM cast = Estimated fugitive PM emissions from casting in tons per year, 0.19 = PM EF for hot metal transfer in pounds per ton of steel produced, P = Reported production of product for the associated furnace in tons per hour, and

15 AP

- 42, Compilation of Air Pollutant Emission Factors, Chapter 12.5 Iron and Steel Production, October 1986. http://www.epa.gov/ttn/chief/ap42/ch12/final/c12s05.pdf (see Table 12.5

- 1)DRAFT FOR INTERNAL REVIEW

22 Capt cast = Estimated capture efficiency of the casting/MOR operations, 8760 = Hours of operation per year, 2000 = Pounds per ton.

The casting/MOR fugitive emissions for metal HAP (e.g., Mn, As, Cd, Cr, Ni, Pb), Cr +6 , HCl , and HF were estimated using the HAP

- to

- PM profile based on furnace emissions of each of the pollutants and multiplying that profile by the estimated casting fugitive PM emission rate. The equation used to estimate these HAP emissions is shown below; ( )

where;

HAP cast = Estimated HAP emissions from casting/MOR in tons per year,

PM cast = Estimated PM emissions from casting/MOR in tons per year,

HAP out = HAP emissions from the associated EAF in tons per year, and

PM out = PM emissions from the associated EAF in tons per year.

Fugitive emissions of mercury from the casting process were calculated using the Hg tapping EFs and a ratio of the tapping and ca sting fugitive PM EFs. The equation for calculating the Hg EF for SiMn production and FeMn/SiMn production is as follows;

( ) ( )

where;

SiMn EF Hg cast = Hg fugitive EF from casting in pounds per ton of SiMn pro duced,
6.85 x 10 - 6 = Hg fugitive EF for tapping in pounds per ton of SiMn produced, 0.19 = PM EF for hot metal transfer in pounds per ton of steel produced, 1.3 = PM fugitive EF for BOF tapping in pounds per ton of steel produced.DRAFT FOR INTERNAL REVIEW

23 Table 5

- 3. Summary of Organic HAP Fugitive Emission Factors for Tapping and Casting at Ferroalloys Production FacilitiesDRAFT FOR INTERNAL REVIEW

24 Th e result of this calculation gives an Hg casting fugitive EF of 1.00 x 10 - 6 pounds per ton of Si Mn produced. Th e same methodology and equation w ere used with the average FeMn/SiMn Hg EF
derived in Section 5.3 to calculate the FeMn/SiMn Hg EF which results in an Hg casting fugitive

EF of 2.63 x 10 - 6 pounds per ton of FeMn/ SiMn produced . These EF s were then used to estimate fugitive Hg emissions from casting from the furnaces at Eramet and Felman using the equation below;

( ) ( )
where;

Hg cast = Estimated fugitive Hg emissions from casting in tons per year,

EF Hg cast = Hg fugitive EF for casting in pounds per ton of product (SiMn or SiMn/FeMn), P = Reported production of product for the associated furnace in tons per hour, and Capt cast = Estimated capture efficiency of the furnace casting operations (see table 5

- 2)

, 8760 = Hours of operati on per year, 2000 = Pounds per ton.

The estimated capture efficiency of the casting operations for each of the furnaces are provided in
Table 5

- 2.

For casting, it was assumed that the fugitive emissions of PCB and CDD/CDF occur during the tapping proces s, but do not occur during the casting process because the se HAPs are products of incomplete combustion and no combustion occurs outside of the furnace . Therefore, only fugitive emissions of PAH and formaldehyde were estimated for casting. The PAH and fo rmaldehyde fugitive emissions from casting were calculated using the same methodology used to estimate fugitive Hg emissions. An EF was developed for each of the organic HAP compounds using the tapping EF and the ratio of the tapping and casting fugitive PM EF s. Again, no distinction was
made between SiMn or FeMn produc tion. As an example, the equation for calculating the naphthalene EF is as follows;

( ) ( )

where;

EF Naphthalene cast = Naphthalene fugitive EF from furnace casting in pounds per ton produced,
7.42 x 10 - 3 = Naphthalene fugitive EF for BOF tapping in pounds per ton of steel produced,
0.19 = PM EF for hot metal transfer in pounds per ton of steel produced, 1.3 = PM fugitive EF for BOF tapping in pounds per ton of steel produced.DRAFT FOR INTERNAL REVIEW

25 This calculation provides a naphthalene casting fugitive EF of 1. 08 x 10 - 3 pounds per ton of FeMn or SiMn produced. This methodology was used to estimate the fugitive PAH and formaldehyde
emissions fa ctor for each of the compounds

. T able 5

- 3 lists the organic HAP fugitive EF s for the tapping process. These EF s and the following equation were used to estimate fugitive PAH and formaldehyde emissions from tapping of the furnaces at Eramet and Felman. An example of the naphthalene fugitive emission calculation is provided below;

( ) ( )
where;

Naphthalene cast = Estimated fugitive naphthalene emissions from casting in tons per year,

EF Naphthalene cast = Naphthalene fugitive EF for casting in pounds per ton of product (SiMn or SiMn/FeMn), P = Reported production of product for the associated furnace in tons per hour, and Capt cast = Estimated capture efficiency of the furnace casting operations (see table 5

- 2)

, 8760 = Hours of operation per year, 2000 = Pounds per ton.

The estimated capture efficienc ies of the casting operations for each of the furnaces are provided in Table 5

- 2.

5.5 Product Crushing Operations Emissions

The product crushing emissions were calculated using the test data provided in the test reports submitted by the facilities. The product crushing and sizing operation at Eramet is controlled by three baghouses. The facility provided test data for one of the baghouses, and the other two baghouse s were assumed to have the same emissions. Felman listed two product crushing and sizing units in their ICR, but noted that only one of the systems is operated.

The hourly emission s reported in the t est report w ere multiplied by the annual hours of operation to estimate the annual emission from the product crusher. In the case of Eramet, the product crushing and sizing system is limited to 5840 hours per year by permit. Therefore, 5840 hours per yea r was used to calculate annual emissions from the Eramet crushing and sizing system. For Felman, the crushing and sizing system was estimated to operate 6240 hours per year. These hours of operation were provided by the facilities in their estimates of b aseline emissions. 16

, 17

16 QSEM Solutions, Inc., Eramet Marietta Inc. Technical Comments to Alternative Approach to NESHAP Subpart XXX Compliance

- November 23, 2011 Proposed Rule, June 29, 2012

. 17 Email from Amy M Lincoln, Beveridge & Diamond, P.C. to Conrad Chin, EPA, RE: Felman Fugitive Emissions Control and Test Protocols , 8/06/2012.DRAFT FOR INTERNAL REVIEW

26 5.6 Product Crushing Operations Fugitive Emissions

The annual fugitive emission s from the product crushing operations were estimated by using the

AP

- 42 EF s for Metallic Minerals Processing. 18 The facilities provided information on the number of emission sources of fugitive emissions from the product and sizing process. These emission
sources were classified in to the following EF groups ; primary crushing, secondary crushing and material handling and transfer. The filterable PM

- 10 EF s were used from each of the classifications
because these are the respirable portion of PM emissions from the crushing and sizing operation.
The EF s for primary crushing, secondary crushing, and material handling an d transfer are 0.05, 0.12, and 0.06 pounds per ton processed respectively. The PM

- 10 EF for secondary crushing was
listed as non

- detect, however the PM

- 10 EF was estimated by reducing the PM EF for secondary crushing by a factor of 10. This is the same fa ctor of reduction that is shown for primary crushing. The fugitive emissions were calculated by totaling the number of each crushing and sizing operation and multiplying that by the emissions factor, capture efficiency, and the crushing and sizing product ion rate as shown in the equation below: [ ∑ ( ) ( ) ]

w here ;

E FCSPM = Estimated fugitive emissions from crushing and sizing in tons per year, ƩCS = Number of crushing, screening, conveyor, or material handling emission points,

EF CS = Crushing, screening, conveyor, or material handling EF in pounds per ton,

P EAF = Crushing and sizing production rate in tons per hour,
CAP CS = Assumed capture efficiency for the crushing and sizing operations (95%),
H = number of ho urs of operation during the year, and 2000 pounds per ton.

The sum of the emissions from the PM fugitive crushing, screening, conveyor, and material handling emission points provides the crushing and sizing fugitive emissions. Metal HAP fugitive
emissions were calculated using the metal HAP

- to

- PM ratio s from the crushing baghouse emissions
data and multiplying that ratio by the calculated fugitive PM emissions for the crushing and sizing fugitives as shown in the equation below. The number of operating hours per year is based on the normal annual operating hours or is limited to the number of ho urs by permit. [ ( ) ( ) ]

where;

18 AP

- 42, Compilation of Air Pollutant Emission Factors, Chapter 11.24 Metallic Mineral Processing, August 1982. http://www.epa .gov/ttn/chief/ap42/ch11/final/c11s24.pdf (see Table 11.24

- 2)DRAFT FOR INTERNAL REVIEW

27 HAP CS = Estimated fugitive HAP emissions from crushing and sizing in tons per year,

PM CS = Estimated fugitive PM emissions from crushing and sizing in tons per year,

HAP CS out = Calculated HAP emissions from crushing and sizing baghouse outlet, and

PM CSout = Calculated PM emissions from crushing and sizing baghouse outlet.

5.7 Baseline Annual HAP Emissions for the Ferroalloy Production Facilities

The baseline annual HAP emiss ions were calculated for each of the previously described emission points and are summarized in Table 5

- 4

. The test data from Eramet Furnace 1 and 12 smelting baghouse outlets and the Furnace 1 tapping baghouse outlet provided HAP emission results for both production of FeMn and SiMn. To estimate the annual HAP emissions f or these emission sources

, it was assumed that both Furnaces 1 and 12 produce Fe Mn 4,380 hours of the year and SiMn is produced 4,380 hours of the year (see section 5.1)

. The furnaces at Felman Production produce only SiMn, and thus no such adjustments to the annual emissions were necessary

. As shown in Table 5

- 4, fugitive emissions were esti mated to be 82 percent of the total HAP emissions from Eramet and 73 percent of the total HAP emissions from Felman.

5.8 Enhanced Capture Annual HAP Emissions for the Ferroalloy Production Facilities

For purposes of the supplemental analysis, we develope d an enhanced capture control option to evaluate residual risk. The enhanced capture annual HAP emissions were calculated assuming 95 percent of fugitive HAP emissions would be captured by the enhanced capture system. Some of the fugitive emission source s were assumed to only use primary capture to achieve 95 percent capture. Other fugitive emission sources were assumed to use both primary and secondary capture to achieve a total of 95 percent capture of fugitive emissions. Captured fugitive HAP emissio ns from the enhanced primary capture system were routed to the assumed source control device and reduced using the control efficiencies listed in Table 5

- 1. Secondary fugitive HAP emissions were assumed to be routed to a new control device and reduced by the control efficiency values listed in Table 5

- 1. A summary of the assumptions and calculations are provided for each of the facilities below. A schematic of the enhanced capture system is provided in Figure 5

- 1.DRAFT FOR INTERNAL REVIEW

28 Table 5

- 4

. Summary of t he Baseline Facility Process Annual HAP Emissions (Tons/year) for the Ferroalloy Production IndustryDRAFT FOR INTERNAL REVIEW

29 Eramet Marietta

The methodology for calculating the enhanced capture emissions from Eramet were based on the proposed fugitive emissions capture plan 19 submitted by the facility. The submitted capture plan proposed increasing the primary capture of fugitive tapping emissions from the furnaces to 95 percent, adding 95 percent primary capture to the casting beds for Furnaces 1 and 1 2, and adding primary and secondary capture to the MOR building to achieve a total capture of 95 percent from the MOR process and MOR casting. A mass balance approach was taken to calculate the enhanced capture emissions from many of the emission sources that are equipped with control devices. Even though, the baghouse or scrubber is a constant outlet device (e.g., the particulate matter concentration in the stack gas is constant), the volumetric flow rate to the control device will
increase due to the ad dition of the enhanced capture fugitive streams, hence increasing the emission rate from the control device outlet. A description of the assumptions used to calculate the enhanced capture emissions from each of the emission sources is provided in the foll owing sections.

Furnace 1 and Associated Emission Sources

The enhanced capture emissions from the Furnace 1 tapping process were calculated assuming an
i ncrease of the primary capture of the fugitive emissions from the estimated 20 percent at baseline

t o 95 percent at the enhanced capture level. The captured emissions from tapping were assumed to be routed to the Furnace 1 baghouse, instead of the dedicated Furnace 1 tapping baghouse. The Furnace 1 baghouse was noted in the control plan to have extra c apacity to control fugitive emission streams from both Furnace 1 tapping and casting. An example of the enhanced capture PM emissions calculation for Furnace 1 tapping fugitives is shown below:

( ) ( )

where;

3.70 = Enhanced capture fugitive PM emissions from Furnace 1 tapping in tons per year, 59.2 = Baseline fugitive PM emissions from Furnace 1 tapping in tons per year, 20% = Baseline capture percent of Furnace 1 tapping emissions, and 95% = Enhance capture percent of Furnace 1 tapping emissions.

19 QSEM Solutions, Inc., Eramet Marietta Inc. Technical Comments to Alternative Approach to NESHAP Subpart XXX Compliance

- November 23, 2011 Proposed Rule, June 29, 2012

.DRAFT FOR INTERNAL REVIEW

30DRAFT FOR INTERNAL REVIEW

31 The enhanced capture casting fugitive emissions from Furnace 1 were also calculated using the same methodology above. The only exception is that there is currently no capture of fugitive
emissions fr om Furnace 1 casting. The control plan submitted by Eramet proposed adding primary capture of 95 percent to the Furnace 1 casting area and routing the captured emissions to the Furnace 1 tapping baghouse, which in the proposed plan will only be used to co ntrol captured fugitive emissions for Furnace 1 casting. An example of the enhanced capture PM emissions calculation for Furnace 1 casting fugitive is shown below:

( )

where;

0.541 = Enhanced capture fugitive PM emissions from Furnace 1 casting in tons per year, 10.8 = Baseline fugitive PM emissions from Furnace 1 casting in tons per year, and 95% = Enhanced capture percent of Furnace 1 casting emissions.

No changes to the capture system for the Furnace 1 smelting operation were proposed in Eramet’s capture plan. The current system was assumed to achieve 98 percent capture of fugitive emission from the furnace operations, therefore the calculated fugitive emissions at the enhanced capture level are the same as the calculated fugitive emi ssions from baseline. There is an increase in the Furnace 1 baghouse outlet emissions in the enhanced capture scenario because the emissions from Furnace 1 tapping, and the Furnace 1 tapping baghouse are now routed to the Furnace 1 baghouse.
The Furnace 1 tapping baghouse was assumed to control captured fugitive emissions from Furnace 12 tapping and Furnace 12 casting in the enhanced capture scenario. The enhanced capture emission rate from the Furnace 1 baghouse outlet was calculated by adding the basel ine emissions from the Furnace 1 baghouse and the Furnace 1 tapping baghouse with the difference of fugitive emissions from Furnace 1 tapping. An example of the PM emissions calculation is shown below:

( 59.2

- 3.70)*(1

- 98%) where;

10.7 = En hanced capture PM emissions from the Furnace 1 baghouse outlet in tons per year, 7.23 = Baseline PM emissions from the Furnace 1 baghouse outlet in tons per year, 2.34 = Baseline PM emissions from the Furnace 1 tapping baghouse in tons per year,
59.2 = Ba seline fugitive PM emissions from Furnace 1 tapping in tons per year, 3.7 = Enhanced capture fugitive PM emissions from Furnace 1 tapping in tons per year, and 98% = Assumed PM control efficiency of the Furnace 1 baghouse.DRAFT FOR INTERNAL REVIEW

32 Note that the control efficiency is only applied to the fugitive casting emissions. The PM emissions from the Furnace 1 baghouse and Furnace 1 tapping baghouse are already provided as controlled
emissions.

As noted in the calculation above, the outlet emissions from the Furnace 1 tapp ing baghouse were moved to the Furnace 1 baghouse in the enhanced capture scenario. This baghouse now controls captured fugitive emissions from Furnace 1 casting in the enhanced capture scenario. The enhanced capture emission rate from this baghouse was calculated by adding the difference of fugitive emissions from Furnace 1 casting. Again, a mass balance approach was taken by subtracting the difference in Furnace 1 casting emissions from baseline to enhanced capture. An example of the
PM emissions calc ulation for the Furnace 1 tapping baghouse is shown below:

( 10.8

- 0.541)(1

- 98%) where;

0.206 = Enhanced capture PM emissions from the Furnace 1 tapping baghouse outlet in tons per

year, 10.8 = Baseline fugitive PM emissions from Furnace 1 casting in tons per year, 3.7 = Enhanced capture fugitive PM emissions from Furnace 1 casting in tons per year, and 98% = Assumed PM control efficiency of the Furnace 1 tapping baghouse.

Furnace 12 and Associated Emission Sources

The enhanced capture emissions fro m the Furnace 12 tapping process were calculated assuming an
i ncrease of the primary capture of the fugitive emissions from the estimated 30 percent at baseline

to 95 percent at the enhanced capture level. The captured emissions from tapping were assumed to be routed to a new Furnace 12 tapping/casting baghouse, instead of the Furnace 12 scrubber. The control noted that the Furnace 12 scrubber did not have the capacity to control the enhanced capture fugitive emission stream from both Furnace 12 tapping. An example of the enhanced capture PM emissions calculation for Furnace 12 tapping fugitives is shown below:

( ) ( )

where;

3.56 = Enhanced capture fugitive PM emissions from Furnace 12 tapping in tons per year,
59.2 = Baseline fugitive PM emissions from Furnace 12 tapping in tons per year, 30% = Baseline capture percent of Furnace 12 tapping emissions, and 95% = Enhance capture percent of Furnace 12 tapping emissions.DRAFT FOR INTERNAL REVIEW

33 The enhanced capture casting fugitive emissions from Furnace 12 were also calculated using the same methodology above. The only exception is that there is currently no capture of fugitive emissions from Furnace 12 casting. The control plan submitted by Eramet proposed adding primary capture of 95 percent to the F urnace 12 casting area and routing the captured emissions to a new Furnace 12 tapping/casting baghouse. An example of the enhanced capture PM emissions calculation for Furnace 12 casting fugitive is shown below:

( ) where;

0.520 = Enhance d capture fugitive PM emissions from Furnace 12 casting in tons per year, 10.4 = Baseline fugitive PM emissions from Furnace 12 casting in tons per year, and 95% = Enhanced capture percent of Furnace 12 casting emissions.

No changes to the capture system for the Furnace 12 smelting operation were proposed in Eramet’s capture plan. The current system was assumed to achieve 98 percent capture of fugitive emission from the furnace operations, therefore the calculated fugitive emissions at the enhanced captur e level are the same as the calculated fugitive emissions from baseline. There is a decrease in the Furnace 12 scrubber outlet emissions in the enhanced capture scenario because the captured emissions from Furnace 12 tapping are now being routed to a dedi cated Furnace 12 tapping/casting baghouse. The enhanced capture emission rate from the Furnace 12 scrubber was calculated by assuming that captured tapping emissions are 8 percent of the total emissions from the furnace control device outlet. Therefore, the enhanced capture Furnace 12 scrubber outlet emissions were assumed to be 92 percent of the baseline Furnace 12 scrubber outlet emissions. An example of the
PM emissions calculation is shown below:

where;

38.7 = Enhanced capture PM emi ssions from the Furnace 12 scrubber outlet in tons per year, 42.1 = Baseline PM emissions from the Furnace 12 scrubber outlet in tons per year, and 0.92 = Assumed fraction of emissions from the furnace smelting process.

As noted above, the captured emissi ons from Furnace 12 tapping and casting are routed to a new Furnace 12 tapping/casting baghouse in the enhanced capture scenario. The enhanced capture emission rate from this baghouse was calculated by adding the difference of fugitive emissions
from both tapping and casting from Furnace 12. An example of the PM emissions calculation for the Furnace 12 tapping/casting baghouse is shown below:DRAFT FOR INTERNAL REVIEW

34 [ ( ) ( ) ( ) ] ( ) where;

1.19 = Enhanced capture PM emissions from the Furnace 12 tapp ing/casting baghouse outlet in tons

per year, 10.4 = Baseline fugitive PM emissions from Furnace 12 casting in tons per year, 0.520 = Enhanced capture fugitive PM emissions from Furnace 12 casting in tons per year, 49.8 = Baseline fugitive PM emissions fr om Furnace 12 tapping in tons per year, 3.56 = Enhanced capture fugitive PM emissions from Furnace 12 tapping in tons per year, 42.1 = Baseline PM emissions from the Furnace 12 scrubber outlet in tons per year, 3.56 = Enhanced capture PM emissions from th e Furnace 12 scrubber outlet in tons per year, and 98% = Assumed PM control efficiency of the Furnace 12 tapping/casting baghouse.

MOR and Associated Emission Sources

The enhanced capture fugitive emissions for the MOR process were calculated based on the control plan submitted by Eramet. The control plan proposed increasing the primary capture of the MOR process and adding secondary capture to the building for an overall capture of 95 percent of fugitive emissions generated by the MOR process. To cal culate this scenario, it was assumed that the primary capture would be increased from 40 percent at baseline to 80 percent at the enhanced capture level. An additional capture of 75 percent was used to estimate the secondary capture effect to the MOR proc ess fugitive emissions. An example of the calculation is shown below:

( ) ( ) ( )

where;

1.06 = Enhanced capture PM emissions from the MOR process in tons per year, 12.7 = Baseline fugitive PM emissions from MOR process in tons per yea r, 40% = Baseline capture percentage of fugitive emissions from the MOR process

, 80% = Primary capture percentage of MOR process fugitives for enhanced capture

, and
75% = Secondary capture percentage of MOR process fugitives for e nhanced capture

.

The en hanced capture MOR casting fugitive emissions were calculated using the same assumptions as above for primary and secondary capture at the enhanced capture level. An example of the enhanced capture PM fugitive emissions from MOR casting is shown below.

( ) ( ) ( )

where;DRAFT FOR INTERNAL REVIEW

35 1.06 = Enhanced capture PM emissions from the MOR casting in tons per year, 12.7 = Baseline fugitive PM emissions from MOR casting in tons per year, 40% = Baseline capture percentage of fugitive emissions from the MOR casting, 80% = Primary capture percentage of MOR casting fugitives for enhanced capture, and 75% = Secondary capture percentage of MOR casting fugitives for enhanced capture.

The enhanced capture emissions from the MOR baghouse were calculated to includ e the primary captured fugitive emissions from the MOR process and MOR casting. An example of the enhanced capture PM emissions from the MOR baghouse is shown below . The equation calculates the MOR fugitive emissions that are only captured by the primary capture system.

[ ( ) ( ) ( ) ( ) ] *(1

- 98%)

where;

3.22 = Enhanced capture PM emissions from the MOR baghouse outlet in tons per year, 12.7 = Baseline fugitive PM emissions from the MOR process in tons per year, 40% = Baseline capture percentage of fugitive emissions from the MOR process, 80% = Primary capture percentage of MOR process fugitives for enhanced capture, 12.7 = Baseline fugitive PM emissions from the MOR casting in tons per year, 40% = Baseline captu re percentage of fugitive emissions from MOR casting, 80% = Primary capture percentage of MOR casting fugitives for enhanced capture, and 98% = Assumed PM control efficiency of the MOR process baghouse.

The fugitive emissions captured by the secondary ca pture system in the MOR building were assumed to be sent to a new MOR secondary baghouse. An estimate of the PM emissions from this baghouse is provided in the calculation below . The equation calculates the fugitive MOR emissions that are only captured b y the secondary capture system.

[ ( ) ( ) ( ) ( ) ] *(1

- 98%)

where;

0.127 = Enhanced capture PM emissions from the MOR secondary baghouse outlet in tons per year, 12.7 = Baseline fugitive PM emissions from the MOR process in tons per year, 40% = Baseline capture percentage of fugitive emissions from the MOR process, 80% = Primary capture percentage of MOR process fugitives for enhanced capture, 1.06 = Enhanced capture PM emissions from the MOR process in tons per year,
12.7 = Baseline fugitive PM emissions from the MOR casting in tons per year, 40% = Baseline capture percentage of fugitive emissions from MOR casting, 80% = Primary capture percentage of MOR casting fugitives for enhanced capture,DRAFT FOR INTERNAL REVIEW

36 1.06 = Enhanced capture PM emissions from the MOR casting in tons per year, and 98% = Assumed PM control efficiency of the MOR secondary baghouse.

Crushing & Screening Operations

The control plan submitted by Eramet did not include any capture enhancements to the crushing
and sizi ng system. Therefore, the enhanced capture crushing and screening baghouse and fugitive
emissions are the same as the calculated baseline emissions for these sources.

Felman Production

The methodology for calculating the enhanced capture emissions from Felman were based on the proposed fugitive emissions capture plan 20 submitted by the facility. The submitted capture plan proposed increasing the primary capture of fugitive and adding secondary capture to the furnace building to achieve an overall capture efficiency of 95 percent. To achieve the overall 95 percent capture, it was assumed that the primary capture would be increased to 80 percent and the secondary capture would capture 75 percent of the remaining fugitive emissions in the building. A

mass balance approach was taken to calculate the enhanced capture emissions from many of the emission sources that are equipped with control devices. A description of the assumptions used to calculate the enhanced capture emissions from each of the emission so urces is provided in the following sections.

Furnace and Associated Emission Sources

Because the furnace smelting, tapping, and casting operation for Furnace 2, 5, and 7 occur in the same building, the same calculation methodology was used for each of these operations. The emissions estimate for fugitive tapping emissions for the enhanced capture scenario were calculated by applying both the primary capture efficiency and the secondary capture efficiency to the tapping operation for Furnaces 2, 5, and 7. An example of the enhanced capture PM tapping fugitive emissions estimate for Furnace 2 is shown in the equation below.

( ) ( ) ( )

Where;

2.88 = Enhanced capture PM fugitive emissions from Furnace 2 tapping in tons per year,

1 7

. 3 = Baseline fugitive PM emissions from Furnace 2 tapping in tons per year,

7 0% = Baseline capture percentage of fugitive emissions from the Furnace 2 tapping

, 80% = Primary capture percentage of furnace tapping fugitives for enhanced capture, and

20 Chu and Gassman, Des ign Narrative, Ju ly 9, 2012

.DRAFT FOR INTERNAL REVIEW

37 75% = Secondary capture percentage of furnace tapping fugitives for enhanced capture.

The casting fugitive emissions are calculated using the same methodology above for tapping fugitive emissions. The emissions estimate for fugitive casting emissions fo r the enhanced capture scenario were calculated by applying both the primary capture efficiency and the secondary capture efficiency to the casting operation for Furnaces 2, 5, and 7. An example of the enhanced capture PM casting fugitive emissions estima te for Furnace 2 is shown in the equation below.

( ) ( ) ( )

Where;

0.420 = Enhanced capture PM fugitive emissions from Furnace 2 casting in tons per year, 5.04 = Baseline fugitive PM emissions from Furnace 2 casting in tons per year, 40% = Baseline capture percentage of fugitive emissions from the Furnace 2 casting, 80% = Primary capture percentage of furnace casting fugitives for enhanced capture, and 75% = Secondary capture percentage of furnace casting fugitives for enhanced captu re.

The proposed control plan submitted by Felman also included changes to the capture of the furnace smelting emissions for Furnace 2, 5, and 7. These changes are expected to increase the fugitive capture from the furnace smelting operations from 98 to 99 percent. Therefore, there is a reduction in the enhanced capture furnace fugitive emissions from Furnaces 2, 5, and 7. An example of the furnace smelting fugitive emission calculation for Furnace 2 is shown below:

( ) ( ) ( )

where ;

1.70 = Enhanced capture PM fugitive emissions from Furnace 2 smelting in tons per year, 13.6 = Baseline fugitive PM emissions from Furnace 2 smelting in tons per year, 98% = Baseline capture percentage of fugitive emissions from the Furnace 2 smelting, 99% = Primary capture percentage of furnace smelting fugitives for enhanced capture, and 75% = Secondary capture percentage of furnace smelting fugitives for enhanced capture.

The furnace baghouse outlet emissions from each of the furnaces increase due to the addition of primary enhanced capture emissions from smelting, tapping, and casting. An example of the PM baghouse outlet emissions from Furnace 2 is shown in the equation below:

[ ( ) ( ) ( ) ( )

( ) ( ) ] ( )DRAFT FOR INTERNAL REVIEW

38 where;

14.8 = Enhanced capture PM emissions from the Furnace 2 baghouse outlet in tons per year,

1 4

. 5 = Baseline fugitive PM emissions from the Furnace 2 baghouse outlet in tons per year, 13.6 = Baseline fugitive PM emissions from Furnace 2 smelting in tons per year, 98% = Baseline capture percentage of fugitive emissions from the Furnace 2 smelting, 99% = Primary capture percentage of furnace smelting fugitives for enhanced capture, 17.3 = Baseline fugitive PM emissions from Furna ce 2 tapping in tons per year, 70% = Baseline capture percentage of fugitive emissions from the Furnace 2 tapping, 80% = Primary capture percentage of furnace tapping fugitives for enhanced capture, 5.04 = Baseline fugitive PM emissions from Furnace 2 cas ting in tons per year, 40% = Baseline capture percentage of fugitive emissions from the Furnace 2 casting, 80% = Primary capture percentage of furnace casting fugitives for enhanced capture, and 98% = Assumed PM control efficiency of the Furnace 2 baghou se.

The Felman control plan proposed that captured secondary fugitive emissions from the furnace smelting, tapping, and casting processes would be controlled by a new secondary furnace baghouse. An example of the calculated PM emissions from this baghous e is shown below:

( ) ( ) ( )

where;

0.742 = Enhanced capture PM emissions from the secondary furnace baghouse in tons per year,

12.4 = Sum of the e nhanced capture fugitive PM emissions from smelting, tapping, and casting for Furnaces 2, 5, and 7 in tons per year, 75% = Secondary capture percentage of the furnace building fugitives for enhanced capture, and 98% = Assumed PM control efficiency of the secondary furnace baghouse.DRAFT FOR INTERNAL REVIEW

39 Crushing & Screening Operations

The control plan submitted by Felman did not include any primary capture enhancements to the crushing and sizing system, but does include secondary capture of fugitive emissions from this process. The secondary fugitive capture syste m for the crushing and screening operation is expected to achieve 75 percent capture. An example of the PM fugitive emissions calculation for the crushing and screening operation is shown below:

( ) where;

2.19 = Enhanced capture fugitive PM emissions from crushing and screening in tons per year, 8.74 = Baseline fugitive PM emissions from crushing and screening in tons per year, and 75% = Secondary capture percentage for crushing and screening.

The Felman control plan proposed that capture d secondary fugitive emissions from the crushing and screening process would be controlled by a new secondary crushing baghouse. An example of the calculated PM emissions from this baghouse is shown below:

( ) ( ) ( )

where;

0.0656 = Enhanced capture PM emissions from the secondary crushing baghouse in tons per year, 2.19 = Enhanced capture fugitive PM emissions from crushing and screening in tons per year, 75% = Secondary capture percentage of crushing fugitives for enhanced capture, and 98% = Assumed PM control efficiency of the secondary crushing baghouse.

A summary of the primary and secondary capture assumptions for fugitive emissions from Eramet
and Felman is provided in Table 5

- 5. A summary of the enhanced capture emissions f or Eramet
and Felman is provided in Table 5

- 6.DRAFT FOR INTERNAL REVIEW

40 Table 5

- 5 . Summary of Fugitive Capture Assumptions Used to Estimate the

Enhanced Capture Emissions

Fugitive Emission Source Enhanced Capture HAP Emission Calculation Assumption

Eramet Marietta

Furnace 1 and 12 Furnace Fugitives No change from baseline . Source is assumed to achieve 98% capture.

Furnace 1 Tapping Fugitives The tapping capture is assumed to increase from 20% at baseline to 95%. Captured emissions routed to Furnace 1 baghouse.
Furnace 12 Tapping Fugitives The tapping capture is assumed to increase from 30% at baseline to 95%. Captured emissions routed to Furnace 12 tapping/casting baghouse (currently Furnace 1 tapping baghouse). Furnace 1 Casting Fugitives The casting capture is assumed to increase from 0% at baseline to 95%. Captured emissions routed to Furnace 1 baghouse. Furnace 12 Casting Fugitives The casting capture is assumed to increase from 0% at baseline to 95%. Captured emissions routed to Furnace 12 tapping/casting baghous e (currently Furnace 1 tapping baghouse).
MOR Process and Casting Fugitives The MOR process and MOR casting primary capture is assumed to increase from 40% at baseline to 80%, and installation of secondary capture of 75% for a total overall capture of 95% . Captured primary emissions routed to MOR baghouse and captured secondary emissions routed to a new MOR s econdary ba ghouse

. Crushing and Sizing Fugitives No change from baseline. Source is assumed to achieve 95% capture.

Felman Production

Furnace 2, 5, 7 Furnace Fugitives The furnace primary capture is assumed to increase from 98% at baseline to 99%, and installation of secondary capture of 75% for a total capture of 99.75%. Captured primary emissions routed to their respective furnace baghouse and c aptured secondary emissions routed to a new secondary baghouse. Furnace 2, 5, 7 Tapping Fugitives The tapping primary capture is assumed to increase from 70% at baseline to 80%, and installation of secondary capture of 75% for a total capture of 95%. Cap tured primary emissions routed to their respective furnace baghouse and captured secondary emissions routed to a new secondary baghouse. Furnace 2, 5, 7 Casting Fugitives The casting primary capture is assumed to increase from 40% at baseline to 80%, and installation of secondary capture of 75% for a total capture of 95%. Captured primary emissions routed to their respective furnace baghouse and captured secondary emissions routed to a new secondary baghouse. Crushing and Sizing Fugitives The crushing an d sizing primary capture is to be 85% , and installation of secondary capture of 75% for a total capture of 9 6 %. Captured primary emissions routed to the crushing and sizing baghouse and captured secondary emissions routed to a new secondary baghouse.DRAFT FOR INTERNAL REVIEW

41 Table 5

- 6

. Summary of the Enhanced Capture Ferroalloys Production F acility Annual HAP Emissions (Tons/year)DRAFT FOR INTERNAL REVIEW

42 In addition to the changes to the fugitive capture efficiencies for enhanced capture, Eramet was also assumed to control mercury emissions from both Furnaces 1 and 12. The mercury emissions are generated during the smelting process from the manganese ore used to produce FeMn and SiMn in both of the furnaces, although there may be trace amounts in the coke or coal used in the smelting

process . The production of FeMn generates considerably more mercury emissions than SiMn production, and is considered to be a significant source of mercury emissions. Since FeMn is produced in each of the furnaces at Eramet, activated carbon injection (ACI) was assumed to be retrofit prior to the control device. The ACI control technology was assumed to achieve 70 percent mercury reduction on Furnace 12 (currently equipped with a venturi scrubber) and 90 percent
reduction on Furnace 1 (currently equipped with a fabric filter). Felman produces only SiMn in each of their three furnaces and was not found to be a significant source of mercury emissions based on the test data results. Therefore, no mercury controls were assumed to be retrofit on the furnace
outlets.

6.0 MODELING DATABASE

Section 112(f)(2) of the Clean Air Act (CAA) directs EPA to assess the risk remaining (residual risk) after the application of maximum achievable control technology (MACT) standards under section 112(d). EPA is to promulgate more stringent standards for a category or subcategory of sources subject to MACT standards under section 112(d) if promulgation of such standards is necessary to protect public health with an ample margin of safety or to prevent (taking into consideration various factors) adverse environmental effects.

In an effort to streamline the process of making residual risk decisions, EPA plans to address residual risk and perform a technology review simultaneously for multiple source categories. For this source category, the first part of this approach is to compile and review facility

- specific data collected by EPA, and to conduct preliminary risk assessments. The risk assessment will include
both chronic and acute inhalatio n risks. The chronic risks are based on long

- term, annual average emissions, while the acute risks are based on short

- term hourly emissions and account for the maximum potential short term emission rates for the industry.

6.1 Chronic Modeling Database

T he chronic modeling database was assembled using the annual pollutant emissions calculated for processes that were tested (e.g., furnace control device outlet, MOR baghouse outlet, crushing and sizing baghouse outlet), and from AP

- 42 EF s for fugitive sourc es that were not tested (e.g., furnace tapping, MOR pouring, crushing and sizing) at each of the ferroalloy facilities. The HAP emissions and the source IDs were then assembled into a database that included other facility descriptors and
emission location parameters (i.e

. , latitude, longitude, emission release height, emission velocity, emission temperature, release length and width). Negative pressure baghouse and scrubberDRAFT FOR INTERNAL REVIEW

43 emission outlets were set up as point sources in the database. Fugitive and posit ive pressure baghouse outlets were set up as area sources.

6.2 Acute Modeling Factors

Rather than developing a separate acute modeling database, acute multipliers were developed for the process emission points. Processes that operate continually, like t he furnace control device outlets, furnace fugitive emissions, and secondary fugitive capture devices, are considered as steady

- state operations

. Estimated yearly emissions from steady

- state emissions points are divided by 8760 to calculate estimated hour ly emissions. Therefore these processes were given an acute multiplier of 1.

Other emission sources such as, tapping fugitives, MOR fugitives, and casting fugitives are the operations that might conceivably result in an emissions spike. These emission points are assumed to operate 25 percent of the time (30 minutes out of each two hour period.) This is a conservative estimate, because it is very unlikely that all furnaces would ever be tapped simultaneously, and it is impossible for tapping a nd casting from a given furnace to occur simultaneously since casting of the molten metal must occur after it is tapped. This methodology is also likely to overestimate the operating frequency of product sizing operations. Following this reasoning, estima ted yearly emissions from intermittent emissions points are divided by 2190 to calculate estimated hourly
emissions. Therefore these processes were given an acute multiplier of 4. A table of the acute multiplier for each of the emissions sources is provi ded in Table 6

- 1.

6.3 MACT Allowables

The modeling emissions calculated from the ICR test data represent an estimate of the mass emissions actually emitted during the specified annual time period. These “actual” emission levels
are often lower than the emission levels that a facility might be allowed to emit and still comply
with the MACT standards. The emissions level allowed to be emitted by the MACT standards is
referred to as the “MACT

- allowable” emissions level. This represents the highest emissio ns level that could be emitted by the facility without violating the MACT standards. The assessment of
these risks at the MACT

- allowable level r eflects the maximum level sources could emit and still comply with national emission standards. For process so urces, the NESHAP specifies numerical emissions limits for particulate matter (as a surrogate for non

- mercury (or particulate) metal HAP) from the electric (submerged) arc furnaces (including smelting and tapping emissions), with the specific limits depend ing on furnace type, size, and product being made. The NESHAP also specifies a numerical concentration limit for PM (as a surrogate for non

- mercury (or particulate) metal HAP) for the crushing and screening process.DRAFT FOR INTERNAL REVIEW

44 Table 6

- 1. Listing of Acute Multipl iers for Ferroalloy Emission PointsDRAFT FOR INTERNAL REVIEW

45 To estimate emissions at the MACT

- allowable level, a ratio of MACT

- allowable to actual
emissions for each of the process source types that are regulated under the existing NESHAP (i.e., furnace control device outlet, MOR baghouse outlet, crushing and screening outlet). This ratio is
based on the maximum emission limits allowed by the MACT standards compared to the reported
actual emissions. T h ese ratios for each emission point type at the facilit ies in this source category
were used to estimate the maximum potential risk estimates that could occur assuming emissions are continuously emitted at the maximum allowed emissions level. Mercury is no t included with
metal HAP because the emissions are not currently regulated by the MACT rule and the emissions are primarily in gaseous elemental form. A table of the MACT

- allowable ratios for metal HAP is presented in Table 6

- 2. An example of the MACT

- al lowable calculation for the Furnace 1 baghouse
is shown below:

( ) ( ) ( ) ( )

where;

0.50 = the assumed fraction of time the facility is producing FeMn or SiMn, 35.9 = the MACT allowable PM emissions rate in pounds per hour when producing SiMn, 29.8 = the MACT allowable PM emission rate in pounds per hour when producing FeMn, 1.79 = the actual average PM emissions rate in pounds per hour based on test data collected during the production of SiMn, and
1.52 = the actual a verage PM emissions rate in pounds per hour based on test data collected during the production of FeMn.

As noted in Section 3.0, Eramet has a third furnace (Furnace 18) that is idle because of damage to the furnace and is unlikely to be repaired and opera ted by the facility in the near future. However, the furnace is still included in their operating permit; t herefore, the emissions will be included in the
allowable emissions file calculations. This is consistent with RTR policy/procedures, which states
that if a process unit and/or facility has not been operating for an extended period of time (years), and is not currently operating, but the unit or facility could theoretically reopen and start again in the future (e.g., still in permit), the emissions s hould not be included in the calculation of “actual” emissions, but should be i nclude d in the estimated potential emissio ns in the “allowables” file.DRAFT FOR INTERNAL REVIEW

46 Table 6

- 2 . Summary of MACT

- Allowable Ratios for Eramet and FelmanDRAFT FOR INTERNAL REVIEW

47 Table 6

- 3 . Summary of Assigned Emission Process Groups for the Ferroalloys SCCDRAFT FOR INTERNAL REVIEW

48 6.4 Emission Process Groups

The emission sources from the test data were divided into emission process groups using the
Standard Classification Codes (SCC) supplied by the facility in the ICR. The emission process groups provided in the SCC list for the Ferroalloys category were; open EAF, fugitive dust sources, raw material crushing and screening operations, casting, and other. T able 6

- 3 presents a summary of the SCC and the assigned emission process group. As shown in Table 6

- 3, the emission process groups assigned in the modeling database for the emission sources were: Open EAF, Raw Material Crushing and Screening Operations, F ugitive Dust Sources, and Casting.

6.5 Latitude/Longitude QA/QC

The latitude and longitude coordinates provided by the facilities were reviewed to ensure that the coordinates matched the location of the emission points. This was done by plotting each emission point on a map of the facility using Google Earth. The plotted emission points were then evaluated in comparison to building layout diagrams provided by the facilities to determine if the emission point matched the expected location of the emissi on point. If it was determined that the emission point did not match the expected location on the diagrams, the point was moved to the expected location and new latitude and longitude coordinates were determined. The map and the emission point coordinate s were sent to the facilities for confirmation of the locations in the December 21,
2013 ICR submittal.

6.6 Stack and Fugitive Parameters QA/QC

The stack and fugitive emission parameters provided by the facility in the ICR were verified to ensure they were correct. The volumetric flow rates for the point sources were checked by calculating the volumetric flow rate using the velocity and duct dimensions. The calculated flow rates were compared with the volumetric flow rates provided in the test reports . If the flow rate difference exceeded 30 percent, engineering judgments were made to revise the velocity or duct dimension data. Fugitive parameters were assigned using the Google Earth map for each of the facilities and estimating the length, width, an d angle of the fugitive emissions. These parameters were sent to the facilities for confirmation of the values that were determined in the December 21,
2013 ICR submittal.