RESULTS OF THE 2013 EMISSIONS TESTING 

SECTION 114 – INFORMATION COLLECTION REQUEST 

(ICR)

Century Aluminum of Kentucky, LLC 

Hawesville, Kentucky

Submitted to: 

Jamie Coomes 

Century Aluminum of Kentucky, LLC 

1627 State Route 271 North 

Hawesville, Kentucky 42303 

Prepared by: 

GEL Engineering, LLC 

Post Office Box 30712 

Charleston, South Carolina 29417 

May 29, 2013 

 
GEL Engineering, LLC 

A Member of The GEL Group, Inc. 

Nsas00713 

RESULTS OF THE 2013 EMISSIONS TESTING 

SECTION 114 – INFORMATION COLLECTION REQUEST (ICR) 

 

Century Aluminum of Kentucky, LLC 

Hawesville, Kentucky

Table of Contents 

Section Subject Page 

 Signature Page .................................................................................................. iii 

 Executive Summary ........................................................................................... iv 

1.0 Introduction ...................................................................................................... 1 

2.0 Testing Event Participants ................................................................................ 1 

3.0 Identification of Substance, Material or Product Sampled .............................. 2 

 3.1 Potline 1-4 EP84 (Stack) .......................................................................... 2 

 3.2 Potline 4 EP88 (Roof Monitor) ................................................................. 2

4.0 Detailed Process Description ............................................................................ 3 

5.0 Test Results ....................................................................................................... 3 

6.0 Identification of Method(s) Used ..................................................................... 4 

 6.1 Stack Sampling Locations ......................................................................... 4 

 6.2 Velocity and Volumetric Flow Rates ........................................................ 4 

 6.3 Dry Molecular Weight .............................................................................. 5 

 6.4 Moisture Content .................................................................................... 5 

 6.5 Emissions Determinations ....................................................................... 5 

 6.5.1 Particulate Matter Emissions Determination .............................. 5 

 6.5.2 Metals Emissions Determination................................. .................. 5 

 6.5.3 POM Emissions Determinations .................................................. 6 

7.0 Date of Performance Test ................................................................................. 6 

8.0 Test Plan and Procedures ................................................................................. 6 

9.0 Identification of Substance, Material or Product Sampled .............................. 6 

10.0 Deviations/Additions/Exclusions – Test Plan/ 

 Test Methods/Quality Manual ......................................................................... 6 

11.0 Specific Test Conditions/Environmental Conditions ........................................ 6 

12.0 Test Results: Uncertainty/Errors/Limiting Conditions ..................................... 6 
ii 

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RESULTS OF THE 2013 EMISSIONS TESTING 

SECTION 114 – INFORMATION COLLECTION REQUEST (ICR) 

 

Century Aluminum of Kentucky, LLC 

Hawesville, Kentucky

Table of Contents (Cont.) 

Section Subject Page 

13.0 Equipment Calibration Certificates .................................................................. 6 

 13.1 Nozzles ..................................................................................................... 7 

 13.2 Pitot Tubes ............................................................................................... 7 

 13.3 Dry Gas Meter .......................................................................................... 7 

 13.4 Thermocouples ........................................................................................ 7 

 13.5 Balance ..................................................................................................... 7 

 13.6 Barometer ................................................................................................ 7 

14.0 Documentation and Sufficient Raw Data to 

 Verify and Reproduce Report Calculations ...................................................... 7 

 

Appendices 

I ERT Reports 

II Summary of Test Results 

III Test Method Formulas and Nomenclature 

IV Field Data Sheets 

V Laboratory Analytical Data 

VI Method 315 Analytical Report 

VII Method 29 Analytical Report 

VIII Facility and Process Data 

IX Equipment Calibration Data 

X Anemometer Readings 
iii 

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Signature Page

This document entitled, “Results of the 2013 Emissions Testing Section 114 – Information 

Collection Request (ICR),” has been prepared and reviewed by the undersigned at the request of 

and for the exclusive use of Century Aluminum of Kentucky, LLC facility located in Hawesville, 

Kentucky. It has been prepared in accordance with accepted quality control practices and it has 

been reviewed by the undersigned. 

 

 Craig McKenzie, QSTI 

 Senior Project Manager 

 

 Kirk Alexander 

 Senior Project Manager 

 

 Keith McCullock 

 Industrial Services Business Unit Manager 

 May 29, 2013 

 

 Date 

 
iv 

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A Member of The GEL Group, Inc. 

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Executive Summary 

Emission testing of the Potline 4 Main Stack and M14 Roof Monitor Downcomer located at the 

Century Aluminum of Kentucky, LLC facility in Hawesville, Kentucky, was performed by GEL 

Engineering, LLC (GEL) personnel on March 12-14, 2013 and May 7-9, 2013. The following table 

provides the measured emission rates: 

EMISSIONS TEST RESULTS 

(Test Run Averages).

Pollutant EPA Method 

Line 1-4 Stack 

(lbs/hr) 

Line 1-4 Stack 

(lbs/ton 

processed)1 

Line 4 

Roof 

Monitor2 

(lbs/hr) 

Downcomer2 

(lbs/ton 

processed) 

PM 17 NA NA 33.22 5.29 

POM 315 4.09 0.163 8.04 1.15 

Antimony 29 1.45E-03 5.78E-05 8.28E-04 1.19E-04 

Arsenic 29 4.87E-03 1.94E-04 1.56E-03 2.23E-04 

Beryllium 29 7.11E-03 2.84E-04 2.14E-03 3.06E-04 

Cadmium 29 1.60E-03 6.38E-05 6.54E-04 9.36E-05 

Chromium 29 1.15E-02 4.58E-04 1.62E-02 2.31E-03 

Cobalt 29 1.56E-03 6.22E-05 3.66E-03 5.24E-04 

Lead 29 2.41E-02 9.63E-04 1.05E-02 1.51E-03 

Manganese 29 1.34E-02 5.33E-04 5.27E-02 7.53E-03 

Nickel 29 4.90E-02 1.96E-03 1.65E-01 2.36E-02 

Mercury 29 6.85E-04 2.74E-05 < 1.23E-03 < 1.76E-04 

Selenium 29 1.18E-03 4.72E-05 6.55E-04 9.37E-05 

1

Note: lbs/ton processed = pounds per ton of aluminum processed. 

2

Note: The mass emissions are based upon the air flow rates taken from the two plant 

 anemometers during testing. The Potline 4 M14 Downcomer total line consists of two rooms. The 

 anemometer readings are provided in Appendix VII. 
GEL Engineering, LLC 

A Member of The GEL Group, Inc. 

Nsas00713 

RESULTS OF THE 2013 EMISSIONS TESTING 

SECTION 114 – INFORMATION COLLECTION REQUEST 

Century Aluminum of Kentucky, LLC 

Hawesville, Kentucky 

1.0 INTRODUCTION 

Stationary source sampling of Potline 4 located at the Century Aluminum of Kentucky, LLC 

(Century Aluminum) facility in Hawesville, Kentucky was performed by GEL Engineering, LLC 

(GEL) personnel on March 12-14, 2013 and May 7-9, 2013. This sampling program entailed 

sampling at two sampling locations; 

• Potline 4 Air Control Stack (Main Stack) – EP84 

• Potline 4 M14 Roof Monitor Manifold Stack (Downcomer) – EP88 

The purpose of this stack testing event was to adhere to an Information Collection Request 

(ICR), issued by the United States Environmental Protection Agency (USEPA) specifically 

pursuant to Clean Air Act (CAA) Section 114 Emissions Data Collection Request for the 

Primary Aluminum Reduction Plant Source Category. 

2.0 TESTING EVENT PARTICIPANTS 

The following table summarizes the participants in the testing event: 

Name Job Title Affiliation 

Craig McKenzie, QSTI Senior Project Manager GEL 

Kirk Alexander, QSTI Senior Project Manager GEL 

Gregg Szymkowicz Field Team Leader GEL 

Charles Rice Sampling Technician GEL 

Sean Huber Sampling Technician GEL 

Derek Anderson Sampling Technician GEL 

Jamie Coomes Environmental Operations Century 

Mr. Craig McKenzie of GEL served as Project Manager, and the client representative for the 

stationary source sampling was Mr. Jamie Coomes. Mr. Craig McKenzie was the Qualified 

Source Testing Individual (QSTI) on site during this testing event. 

3.0 IDENTIFICATION OF SUBSTANCE, MATERIAL OR PRODUCT SAMPLED 

Pursuant to the guidelines of the ICR notification, Century Aluminum submitted past testing 

data on targeted sources to the EPA on March 22, 2013. Upon review, the USEPA outlined 

specific sources and parameters to be tested. The specific sources targeted for this ICR and 
Results of the 2013 Emissions Testing of Line 4 May 29, 2013 

Main Stack and Downcomer Page 2 

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parameters are as follows: 

3.1 Potline 1-4 Stack (EP84) 

Emissions tests were conducted on the exhaust stack using the EPA methodologies listed 

below: 

Parameter Method(s) Duration 

Gas Velocity and Volume Flow Rates 1 & 2 as required 

O2/CO2 3 as required 

Moisture Content 4 as required 

Metals 129 3 four-hour runs 

Polycyclic Organic Matter (POM) 315 6 three-hour 

runs 

**Notes: 

 

1 Metals targeted included antimony, arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, 

 nickel, selenium and mercury. 

3.2 Potline 4 Roof Monitor (EP88) 

Emissions tests were conducted on the Line 4 permanently installed manifold system, using 

the EPA methodologies listed below: 

Parameter Method(s) Duration 

Gas Velocity and Volume Flow Rates 14 as required 

O2/CO2 3 as required 

Moisture Content 4 as required 

PM 17 6 four-hour runs 

Metals 129 3 four-hour runs 

POM 315 6 three-hour 

runs 

**Notes: 

 

1 Metals targeted included antimony, arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, 

 nickel, selenium and mercury. 

Please note all emissions testing were conducted on the Line 4 manifold during the night 

shifts. This was done to perform the testing during the anode changes as detailed by the 

ICR notification. During each test run, multiple anodes were set along Line 4. A process log 

of the anode setting is included in Appendix VIII. 
Results of the 2013 Emissions Testing of Line 4 May 29, 2013 

Main Stack and Downcomer Page 3 

Century Aluminum of Kentucky, LLC, Hawesville, Kentucky 

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A Member of The GEL Group, Inc. 

Nsas00713 

Line 4 consists of two buildings, with each building containing two sections. The ICR testing 

of the Line 4 Roof Manifold followed the guidelines of EPA Method 14. The Summary of 

Results for the Downcomer sampling is detailed in the EPA Electronic Reporting Tool (ERT). 

Whereas, the Summary of Test Results for the Testing Section of Line 4 and entire line 

emissions factors are detailed in Appendix II. 

4.0 DETAILED PROCESS DESCRIPTION 

Century’s Kentucky facility is located in Hancock County near Hawesville. 

Century is a primary aluminum reduction facility that produces aluminum by the 

electrolytic reduction of aluminum oxide (alumina). Alumina arrives at the plant via 

barge or rail transport for reduction to aluminum in shallow rectangular cells called 

“pots.” These pots are carbon steel shells and are arranged electrically in series to 

form a potline. The building that houses the potline is divided into two rooms by a 

center aisle. Each section of the line is called a potroom and each potroom has a 

dedicated roof monitor. 

To facilitate the electrolytic reduction of alumina to aluminum, prebaked carbon 

blocks or anodes are suspended and extended into the pot. These anodes serve as 

the means of introducing the electrical current to the pot. The lined shell acts as 

the cathode to complete the circuit. The pots contain alumina and cryolite that acts 

as the catalyst for the reaction. Other materials are also added to assist in the 

reaction. Molten aluminum is tapped from the pots and transferred to the 

casthouse for further processing. Emissions from the process are captured by the 

shields that cover the pots and are transported to the emission control system for 

treatment. Fugitive emissions that escape from the pots when alumina is added or 

when anodes are replaced exhaust to the atmosphere through the roof monitors. 

Potlines One through Four commenced operation in 1969 and are considered 

Center-Worked Prebake 3 (CWPB 3) potlines subject to a NESHAP emissions limit for 

Total Fluoride of 2.5 lbs per ton of aluminum produced. 

5.0 TEST RESULTS 

Tests runs measuring the target parameters detailed in Sections 3.1 through 3.2 of this 

report were performed on March 12-14, 2013 and May 7-9, 2013. The test results 

obtained for this sampling program are summarized in the Executive Summary. As per the 

guidance provided in the EPA’s ICR notification, all emissions data from Methods 17, 29, 

and 315 were entered into the EPA ERT and submitted as per the ICR guidance. Also, the 

summary of the Line 4 Roof Monitor Method 14 calculations, which are not supported by 

the ERT, are detailed in the Summary of Test Results. All emissions testing followed the 

directives cited in Tables 1.1 and 1.2 of the ICR notification in regards to sources targeted, 

minimum sample volume collected, and units of measurements (pounds per hour and 

pounds per ton aluminum produced). The ERT reports for each source are included in 

Appendix I. The Summary of Test Results for the Method 14 testing is included in Appendix 
Results of the 2013 Emissions Testing of Line 4 May 29, 2013 

Main Stack and Downcomer Page 4 

Century Aluminum of Kentucky, LLC, Hawesville, Kentucky 

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A Member of The GEL Group, Inc. 

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II.

6.0 IDENTIFICATION OF METHOD(S) USED 

Test parameters and sampling methods for the test program are summarized in Table 1. 

Sampling methods and analytical procedures recommended by the EPA were used during 

this test program. Laboratory and calibration procedures described in EPA Quality 

Assurance Handbook for Air Pollution Control Systems, Vol. III, (EPA/600/R-94/038c), and 

the QA/QC procedures specified in EPA Reference Methods 1, 2, 3, 4, 14, 17, 29, and 315 

were followed during execution of the test program. The sampling and analytical 

methodologies are described below. 

6.1 Stack Sampling Locations 

EPA Method 1 was used to determine the number and location of the sampling points for 

flow determination for both the Main and Downcomer Stacks. The test points for the both 

sources are presented in Appendix IV. The Main Stack is a 311.75-inch diameter stack and 

the sampling platform is located approximately 300 feet above the base of the stack. As 

specified by Method 1, a horizontal cross section of each stack was divided 12 equal areas 

with 3 traverse points located on each of four perpendicular diameters.

The Downcomer stack is a 14-inch diameter stack. As specified by Method 1, a horizontal 

cross section of each stack was divided 12 equal areas with 6 traverse points located on 

each of two perpendicular diameters. Potline 4 consists of two buildings, each with two 

rooms. Each section of the Potline 4 measures 459 feet and 5 inches in length and 19 feet 

and 4 inches in width. The Potline 4 Roof Monitor follows the guidelines of EPA Method 

14, with relation to eight manifold nozzles per section and two anemometers position 

along the testing section. The Downcomer sampling location is located in a building along 

Line 4. 

6.2 Velocity and Volumetric Flow Rates 

EPA Method 2 was used to determine the stack gas velocity and volumetric flow rates for 

the Main Stack. Velocity and volumetric flow rates were calculated based on the average of 

the measurements for each test run. The temperature of the stack was measured by a 

calibrated Type K Thermocouple positioned in the stack in accordance with EPA Method 2. 

EPA Method 14 was used to determine the stack gas velocity and volumetric flow rates for 

the Downcomer Stack. Velocity and volumetric flow rates were calculated based on the 

average of velocity traverses performed before and after each test run. Concurrent 

readings from two plant anemometers were also recorded during each test run. The 

anemometers are continuously recording the flows. These readings were averaged and 

used to determine the Roof Monitor exhaust rate for one section. Since an entire line 

consists of two rooms, the exhaust rate for the entire line is by multiplying the emissions 

results by 4 to calculate pounds per hour. All guidelines were followed as per Method 14 

for calculations and isokinetic verifications. 
Results of the 2013 Emissions Testing of Line 4 May 29, 2013 

Main Stack and Downcomer Page 5 

Century Aluminum of Kentucky, LLC, Hawesville, Kentucky 

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6.3 Dry Molecular Weight 

In accordance with the guidelines in EPA Method 2, the dry molecular weight was assumed 

to be that of ambient air or 29.0.

6.4 Moisture Content

EPA Method 4 was used to determine the moisture content of the stack gas. Following the 

protocol given in Method 4, the volume of the condensed water vapor collected in the 

impingers and the silica gel were weighed before and after sample collection. The 

difference in the two weights of the silica gel, the difference in the two weights of 

condensed water vapor captured in the impingers, and the volume of air sampled with the 

impingers train were used to calculate the moisture content of the stack gas. 

6.5 Emissions Determinations 

Sampling methods and analytical procedures recommended by the EPA were used 

during this test program. The sampling and analytical methodologies are described 

below. 

6.5.1 PM Emissions Determination 

A total of six, 4-hour test runs using EPA Method 17 to determine the PM emission rate 

were conducted on the Line 4 Roof Monitor May 7-9, 2013. Particulate emissions were 

collected isokinetically through a stainless steel sampling head which contained a stainless 

steel filter holder with a quartz fiber filter. The gas then traveled through a heated probe 

to the impinger train. 

Upon completion of each sampling run, the sampling head was removed from the probe 

and allowed to cool prior to sample recovery. Sample recovery consisted of acetone rinses 

of the nozzle and filter head prior to the filter. The quartz fiber filter was also recovered at 

the end of each sampling run for PM determination. The Method 17 weight sheets are 

included in Appendix V. 

6.5.2 Metals Emissions Determinations 

Three 4-hour test runs were conducted using EPA Method 29 to determine the emission 

rates for the target metals at the Line 1-4 Stack and Line 4 Roof Monitor. Emissions were 

collected isokinetically through a heated sampling probe onto heated high purity quartz 

fiber filters. The sampling train was equipped with a glass nozzle, a glass probe liner, a 

quartz fiber filter, two impingers charged with nitric acid and hydrogen peroxide solution 

(5% HNO3/10% H2O2), an empty impinger, two impingers charged with potassium 

permanganate/sulfuric acid solution (4% KMnO4/10% H2SO4) and an impinger charged with 

silica gel. The sample train nozzle and probe were rinsed and scrubbed with acetone until 

clean in the field. The cyclone bypass and front half of the filter housing were rinsed and 

scrubbed with acetone until clean upon return to the laboratory. The acetone rinse from 

each run was collected and analyzed with the collected filters to determine PM emissions. 

The sample train components, including the nozzle, probe, and filter housing, were rinsed 
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and scrubbed with the appropriate rinse solutions until clean for metals analysis. The 

impinger solutions, the rinse solutions, and the filters collected from each run and a field 

blank was then submitted to Element One, Inc. (Element One), digested, and analyzed to 

determine metals emissions. Recovery of moisture train and probe rinses were performed 

in the field while filter recovery and filter bell rinses were performed at GEL. 

6.5.3 Polycyclic Organic Matter Emissions Determinations 

A total of three, 3-hour test runs on Line 1-4 Stack and six, 3-hour runs for the Line 4 Roof 

Monitor using EPA Method 315 to determine the POM emission rates were conducted. 

The sampling train was equipped with a Pyrex nozzle and probe liner, a high purity quartz 

filter, one Greenburg-Smith impinger and one standard impinger both charged with 

deionized water, one empty standard impinger, and one impinger charged with silica gel. 

POM emissions were collected isokinetically through the nozzle and probe onto the heated 

filter. The sample train components, including the nozzle, probe, and filter housing, were 

rinsed and scrubbed until clean after each test run as per EPA Method 315. The samples 

were marked, labeled, and shipped to Resolution Analytics for analysis. 

7.0 DATE OF PERFORMANCE TEST 

The performance test was conducted on March 12-14, 2013 and May 7-9, 2013. 

8.0 TEST PLAN AND PROCEDURES 

A test plan was submitted to DEP by Century Aluminum for this performance test. Refer to 

Table 1 for a summary of the test parameters and sampling methods for the test program. 

9.0 IDENTIFICATION OF SUBSTANCE, MATERIAL OR PRODUCT SAMPLED 

Emission testing of the exhaust flue gas of Line 4 main exhaust stack was performed for 

Metals and POM. The Line 4 Downcomer was also tested for PM, metals, and POM. 

10.0 DEVIATIONS/ADDITIONS/EXCLUSIONS – TEST PLAN/TEST METHODS/QUALITY 

MANUAL 

A test plan was required for this performance test. The performance test was executed 

without any deviations, additions or exclusions to the test methods detailed in the test plan 

and GEL’s quality manual. 

11.0 SPECIFIC TEST CONDITIONS/ENVIRONMENTAL CONDITIONS

The Line 4 process was operating under normal conditions. 

12.0 TEST RESULTS: UNCERTAINTY/ERRORS/LIMITING CONDITIONS 

The performance test was performed as per the test methods. There were no limiting 

conditions or errors during the execution of this testing event. 

13.0 EQUIPMENT CALIBRATION CERTIFICATES 

Equipment calibration data is included in Appendix IX. 
Results of the 2013 Emissions Testing of Line 4 May 29, 2013 

Main Stack and Downcomer Page 7 

Century Aluminum of Kentucky, LLC, Hawesville, Kentucky 

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13.1 Nozzles

Each nozzle is purchased from a stack testing equipment supplier and inspected and 

calibrated before putting it into field use. Thereafter, it is inspected prior to use and if 

damaged, the nozzle is not used. A set of three measurements is made prior to use and 

must be within 0.002 inches. Nozzles are checked prior and after each source test. 

13.2 Pitot Tubes

All pitot tubes used by GEL are purchased along with the probe assembly from a stack 

testing equipment supplier. Prior to being used, the pitot tubes are calibrated as per 

Method 2. Pitot tubes are inspected before each source test and receive a complete 

calibration once per year. 

13.3 Dry Gas Meter 

Complete dry gas meter calibrations are performed annually. After a source test, a single 

point calibration is conducted at the average orifice meter (DH) and maximum vacuum 

readings encountered during the test. If the dry gas meter calibration factor differs from 

the annual calibration by more than +/- 0.05, it is repaired and given another annual 

calibration. 

13.4 Thermocouples

Each new thermocouple purchased by GEL is checked and calibrated prior to use. After 

each source test, all temperature-sensing devices used receive a one-point calibration 

check as per Method 2. 

13.5 Balance

GEL technicians utilize an Ohaus Model E12140 Serial No. G2391121320091P balance. 

The serial number for the calibration weight set is 39325. A copy of the calibration log will 

be provided upon request. 

13.6 Barometer

GEL utilizes the National Weather Service to determine the current barometric pressure. 

This is obtained either by telephone or using the Internet. 

14.0 DOCUMENTATION AND SUFFICIENT RAW DATA TO VERIFY AND REPRODUCE 

REPORT CALCULATIONS 

Test method formulas and nomenclature are included in Appendix III. The field data sheets 

for this testing event are included in Appendix IV. The laboratory analytical data is included 

in Appendices V, IV, and VII. Facility process data is included in Appendix VIII.