February 19, 2010 

Steve Wright 

Columbia Falls Aluminum Company, LLC 

2000 Aluminum Drive 

Columbia Falls, MT 59912 

RE: Compliance Monitoring Report (CMR) and Full Compliance Evaluation (FCE) 

Dear Mr. Wright: 

Enclosed is a copy of a CMR for the Columbia Falls Aluminum Company, LLC (CFAC) aluminum 

smelting facility. This report covers the period from April 17, 2008, to February 19, 2010, and 

documents a FCE for the same period. During the most recent inspection, the facility appeared to 

be in compliance with all of the applicable conditions and limitations contained in CFAC’s air 

quality permits. 

Should you have any questions or comments about this report, please contact me at (406) 444-4114. 

Sincerely, 

Robert Gallagher 

Environmental Engineer Specialist 

Air Resources Management Bureau 

E-mail: rgallagher@mt.gov

Enclosure 

cc: Betsy Burns, EPA – Montana 

Wendee Jacobs, Flathead City – County Health Department
MONTANA DEPARTMENT OF ENVIRONMENTAL QUALITY 

AIR RESOURCES MANAGEMENT BUREAU

COMPLIANCE MONITORING REPORT 

This report includes a full compliance evaluation, with any partial evaluations and any investigations 

conducted for the period from April 17, 2008, to February 19, 2010. 

Inspector: Robert Gallagher 

Report Date: February 19, 2010 

I. Facility Information 

A. Facility Name: Columbia Falls Aluminum Company, LLC 

 Location: Section 3, Township 30 North, Range 20 West, Flathead County 

 Latitude: 48.3928 Longitude: -114.13969 

Mailing Address: 2000 Aluminum Drive Columbia Falls, MT 59912 

B. Source Contact(s): Steve Wright – Environmental Manager

 Telephone #: (406) 892-8211 

C. Title V Designation 

 (CDS Class): A – Major 

D. Mega-Site Designation: No

E. SIC Code: 3334 – Primary Aluminum Production

NAICS Code: 331312 – Primary Aluminum Production 

 F. AIRS ID #: 30-029-0012 

 

G. Permit #: Montana Air Quality Permit (MAQP) #2655-05 

Montana Air Quality Operating Permit (MAQOP) #OP2655-02 

 

H. Area Attainment Status: Attainment, but Adjacent to the Columbia Falls Particulate Matter 

with 

an aerodynamic diameter less than or equal to 10 microns (PM10) 

Non-attainment area 

 

I. AFS Action Form Submitted for Full Compliance Evaluation: Yes 

II. General Plant Description: 

 

Columbia Falls Aluminum Company, LLC (CFAC) operates five vertical stud Soderberg potlines at the 

Columbia Falls plant. Each potline has 120 individual cells that produce aluminum by the Hall-Heroult 

process. The Columbia Falls plant’s annual operating capacity is approximately 185,000 tons of 

aluminum, based on an average current efficiency of 90.5%. 

 

The Hall-Heroult process consists of passing an electric current through aluminum oxide ore, or 

alumina (Al2O3), dissolved in molten cryolite. The reduction process takes place in a vertical stud 

Soderberg style pot. Soderberg technology describes the type of consumable carbon anode used in the 
process. 

Buildings, called potrooms, house the cells or “pots”. Two potrooms connected electrically in series 

form one potline. CFAC has 10 potrooms that comprise the five potlines. Emissions from each pot are 

divided into two categories, primary emissions and secondary emissions. The primary-air-pollutioncontrol system treats the primary emissions captured at the pots to remove gaseous and particulate 

emissions. This control system is an Alcoa designed A398 dry-alumina scrubber. Secondary emissions 

are fugitive emissions from the pots vented out the roofline of the potrooms. 

 

A molten bath of cryolite, heated to about 950°C (1740°F) receives alumina. Through the 

electrochemical process, electricity passes from the anode to the cathode, causing the reduction of 

aluminum. The aluminum metal sinks below the cryolite bath forming a molten aluminum “pad.” The 

evolved oxygen atoms bond with the carbon in the anode of the cell forming carbon monoxide and 

carbon dioxide. Other emissions from the process include particulate fluoride and gaseous hydrogen 

fluoride as well as hydrocarbon emissions containing polycyclic organic matter (POM). The aluminum 

metal is siphoned from the pot every 48-hours and transported to the Casting Department, where it is 

cast into ingots of various sizes, shapes and alloys. Each pot produces approximately 1,700 pounds of 

aluminum per day. 

 

III. Applicable Air Programs: 

A. State Implementation Plan (SIP) – CFAC has the potential to emit greater than 25 tons per year 

(TPY) of PM10, carbon monoxide (CO), oxides of nitrogen (NOx), sulfur dioxide (SO2), and volatile 

organic compounds (VOC); therefore, an MAQP is required. MAQP #2655-05 has been issued by 

the Department of Environmental Quality – Air Resources Management Bureau (Department) and 

lists the conditions under which CFAC must operate to be in compliance with the SIP. 

B. New Source Performance Standards (NSPS) – CFAC is not an affected facility under NSPS 

Subpart S – Standards of Performance for Primary Aluminum Reduction Plants because none of the 

units in the subpart that are present at CFAC were constructed or modified after October 23, 1974. 

C. Prevention of Significant Deterioration (PSD) – This facility is subject to PSD, because it is a 

listed source and has potential emissions greater than 100 TPY for PM10, CO, SO2, and VOC. 

D. Title V Program – CFAC is a major source under the Title V Operating Permit program because 

the facility has potential emissions greater than 100 TPY. The facility currently operates under 

MAQOP #OP2655-02. 

E. Maximum Achievable Control Technology (MACT) – CFAC is subject to: 

• Primary Aluminum Smelter MACT (40 Code of Federal Regulations (CFR) 63, Subpart 

LL), and 

• Secondary Aluminum Smelter MACT (40 CFR 63, Subpart RRR) for parts of the Casting 

operation. 

F. Acid Rain – CFAC is not subject to the Acid Rain program because it is not designed to produce 

electricity. 

IV. Applicable Requirements:

The following table includes a list of the emitting units and the most recent observation of those units. 

The observations recorded are from the January 14, 2010, on-site inspection unless otherwise noted. 
Summary of Emitting Units and Compliance Observation 

Emission 

Unit ID 

Emission Unit 

Description 

Pollution Control Device 

Or Practice Observations 

EU001 Ball Mill North – MH01 Baghouse Out of Service

EU002 Ball Mill South – MH02 Baghouse Out of Service

EU003 Coke Silo – MH04 Baghouse Out of Service

EU004 East Alumina Elevator – MH06 Baghouse Out of Service

EU005 East Alumina Unloading – MH07 Baghouse Out of Service

EU006 East Conveyor Storage – MH08 Baghouse Out of Service

EU007 West Alumina Unloading – MH09 Baghouse Out of Service

EU008 Anode Dust Control System – MH03 Baghouse Out of Service

EU009 Coke Unloading – MH05 Baghouse Out of Service

EU010 West Conveyor Storage – MH10 Baghouse Out of Service

EU011 Potline Sweeping – AR04 Baghouse Out of Service

EU012 Treatment of Aluminum Crucibles 

(TAC) Operations – CO10 Baghouse Out of Service

EU013 Pin Cleaning – West Plant – CR07 Baghouse Out of Service

EU014 Pin Cleaning – East Plant – CR07a Baghouse Out of Service

EU015 Paste Plant Extruder – PP01 Dry Coke Scrubber (Baghouse) Out of Service

EU016 Paste Plant Mixer – PP02 Dry Coke Scrubber (Baghouse) Out of Service

EU017 Pinhole Paste Drying – PP03 Baghouse Out of Service

EU018 Pitch Storage Tank Vents – PP04 Condensation Tower/Vent Out of Service

EU019 Therminol Oil Heating System – PP05 None Out of Service

EU020 East Plant Dry Scrubber Alumina 

Transfer (North) – AR01 Baghouse Out of Service

EU021 East Plant Dry Scrubber Alumina 

Transfer (South) – AR02 Baghouse Out of Service

EU022 West Plant Dry Scrubber Alumina 

Transfer (North) – AR06 Baghouse Out of Service

EU023 West Plant Dry Scrubber Alumina 

Transfer (South) – AR07 Baghouse Out of Service

EU024 Primary Gas Collection System – West 

Plant (Potlines 1 & 2) – AR05 

Dry Alumina Scrubber #1 

(Reactor #1 & Baghouse) Out of Service

EU025 Primary Gas Collection System – West 

Plant (Potlines 1 & 2) – AR05 

Dry Alumina Scrubber #2 

(Reactor #2 & Baghouse) Out of Service

EU026 Primary Gas Collection System – West 

Plant (Potlines 1 & 2) – AR05 

Dry Alumina Scrubber #3 

(Reactor #3 & Baghouse) Out of Service

EU027 Primary Gas Collection System – West 

Plant (Potlines 1 & 2) – AR05 

Dry Alumina Scrubber #4 

(Reactor #4 & Baghouse) Out of Service

EU028 Primary Gas Collection System – East 

Plant (Potlines 3, 4, & 5) – AR05 

Dry Alumina Scrubber #5 

(Reactor #5 & Baghouse) Out of Service

EU029 Primary Gas Collection System – East 

Plant (Potlines 3, 4, & 5) – AR05 

Dry Alumina Scrubber #6 

(Reactor #6 & Baghouse) Out of Service

EU030 Primary Gas Collection System – East 

Plant (Potlines 3, 4, & 5) – AR05 

Dry Alumina Scrubber #7 

(Reactor #7 & Baghouse) Out of Service

EU031 Primary Gas Collection System – East 

Plant (Potlines 3, 4, & 5) – AR05 

Dry Alumina Scrubber #8 

(Reactor #8 & Baghouse) Out of Service

EU032 Primary Gas Collection System – East 

Plant (Potlines 3, 4, & 5) – AR05 

Dry Alumina Scrubber #9 

(Reactor #9 & Baghouse) Out of Service

EU033 Primary Gas Collection System – East 

Plant (Potlines 3, 4, & 5) – AR05 

Dry Alumina Scrubber #10 

(Reactor #10 & Baghouse) Out of Service

EU034 Potline #1 Roof Vent, West Plant None Out of Service

EU035 Potline #2 Roof Vent, West Plant None Out of Service

EU036 Potline #3 Roof Vent, East Plant None Out of Service
Emission 

Unit ID 

Emission Unit 

Description 

Pollution Control Device 

Or Practice Observations 

EU037 Potline #4 Roof Vent, East Plant None Out of Service

EU038 Potline #5 Roof Vent, East Plant None Out of Service

EU039 Casting Furnace #3 – CO01 None 

The Secondary Aluminum MACT 

covers the Casting Operations. The 

MACT II regulates reactive fluxing 

in the furnaces. The MACT II 

Prohibits use of Chlorine, without 

additional record keeping. 

EU040 Casting Furnace #4 – CO02 None 

EU041 Casting Furnace #6 – CO03 None 

EU042 Casting Furnace #7 – CO04 None 

EU043 Casting Furnace #8 & #9 – CO05 None 

EU044 Casting Pit #3 – CO06 None 

EU045 Casting Pit #4 – CO06 None 

EU046 Casting Pit #6 & #7 – CO06 None 

EU047 Casting Pit #8 & #9 – CO06 None 

EU048 Dross Handling – CO07 None 

EU049 Sheet Ingot Saw – CO08 Target Box and Cyclone Out of Service

EU050 T-Ingot Saw – CO09 Target Box and Filter or Cyclone Out of Service

EU051 Sandblasting Activities – CR01 None Out of Service

EU052 Lectromelt Furnace – CR03 Baghouse Out of Service

EU053 Rod Mill / Material Storage – CR04 Baghouse Out of Service

EU054 Change House Boiler #1 – MP01 None 

All Boilers are Natural Gas Fired 

Boilers. The Annual Certification 

shows that only natural gas or 

propane fuels these units. See annual 

Certification received 1/20/10. 

EU055 Change House Boiler #2 – MP02 None 

EU056 Lab Boiler #1 – MP07 None 

EU057 Machine Shop Boiler #1 – MP08 None 

EU058 Machine Shop Boiler #2 – MP09 None 

EU059 Paste Plant Boiler #1 – MP11 None 

EU060 Paste Plant Boiler #2 – MP12 None 

EU061 Warehouse Boiler #1 – MP16 None 

EU062 Warehouse Boiler #2 – MP17 None 

EU063 Haul Road Emissions – MP05 None Out of Service 

EU064 Gasoline Storage Tank – MP04 None OK by design of system. See annual 

Certification received 1/20/10. 

The following tables outline the applicable requirements, emissions limitations, and the compliance 

status for the emitting units during the period covered by this Compliance Monitoring Report (CMR). 

A. FACILITY-WIDE 

Condi

-tion Rule Citation Rule Description Pollutant/Parameter Limit Compliance 

Status 

A.1 ARM 17.8.331 Fluoride Emissions Fluoride emissions 

2.6 lbs/ton of alum. 

produced, averaged 

over calendar month 

OUT* 

A.2 ARM 17.8.332 Visible Air Contaminants 

from Potroom Opacity 10% IN 

A.3 ARM 17.8.749 Particulate Matter, 

Airborne Fugitive Emissions Controlled by 

Baghouse IN 

A.4 ARM 17.8.308(2) Particulate Matter, 

Airborne Reasonable Precaution 0.02 gr/dscf IN 

A.5 ARM 17.8.308(3) Particulate Matter, 

Airborne 

Reasonable Precaution, 

Construction 20% IN 

A.6 ARM 17.8.309 Particulate Matter, Fuel 

Burning Equipment Particulate Matter E = 0.882 * H-0.1664 Or 

E = 1.026 * H-0.233 IN 

A.7 ARM 17.8.310 Particulate Matter, 

Industrial Processes Particulate Matter E = 4.10 * P0.67 Or 

E = 55 * P0.11- 40 IN 

A.8 ARM 17.8.322(4) Sulfur Oxide Emissions, 

Sulfur in Fuel 

Sulfur in Fuel (liquid or 

solid fuels) 1 lb/MMBtu Fired IN 

A.9 ARM 17.8.322(5) Sulfur Oxide Emissions, Sulfur in Fuel (gaseous) 50 gr/100 CF IN 
Condi

-tion Rule Citation Rule Description Pollutant/Parameter Limit Compliance 

Status 

Sulfur in Fuel 

A.10 ARM 17.8.324(3) Hydrocarbon Emissions, 

Petroleum Products Gasoline Storage Tanks ------- IN 

A.11 ARM 17.8.324 Hydrocarbon Emissions, 

Petroleum Products 65,000-Gallon Capacity ------- IN 

A.12 ARM 17.8.324 Hydrocarbon Emissions, 

Petroleum Products 

Oil-effluent Water 

Separator ------- IN 

A.13 ARM 17.8.1212 Reporting Requirements Compliance Monitoring ------- IN 

A.14 ARM 17.8.1207 Reporting Requirements Annual Certification ------- IN 

A.15 ARM 17.74.336 Asbestos Asbestos ------- IN 

A.16 40 CFR Part 63, 

Subpart LL Aluminum MACT Fluoride, Polycyclic 

Organic Matter See Appendix G IN 

*Violation Letter #VLRAG09-21 was issued for exceeding the fluoride emissions limit during July 2009. 

 

B. EU001 – EU007 MATERIAL HANDLING EMITTING UNITS WITH BAGHOUSES 

EU001 – Ball Mill North EU003 – Coke Silo 

EU002 – Ball Mill South 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

B.1, B.4, 

B.5, B.7, 

B.9 

Opacity 20% Method 9 As Required by 

the Department Semiannual IN 

Baghouse I & M (Append. K) Ongoing Semiannual IN

B.3, B.6, 

B.8, B.9 

Particulate 

Matter E = 55*P0.11 – 40 Method 5 As Required by 

the Department Semiannual IN

EU004 – East Alumina Elevator 

EU005 – East Alumina Unloading 

EU006 – East Conveyor Storage 

EU007 – West Alumina Unloading 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

B.2, B.4, 

B.5, B.7, 

B.9 

Opacity 40% Method 9 As Required by 

the Department Semiannual IN

Baghouse I & M (Append. K) Ongoing Semiannual IN

B.3, B.6, 

B.8, B.9 

Particulate 

Matter E = 55*P0.11 – 40 Method 5 As Required by 

the Department Semiannual IN

C. EU008 – EU014 EU’S WITH BAGHOUSES & GRAIN LOADING RESTRICTIONS 

EU008 – Anode Dust Control System EU012 – Treatment of Aluminum Crucibles 

EU009 – Coke Unloading EU013 – Pin Cleaning - West Plant 

EU010 – West Conveyor Storage EU014 – Pin Cleaning - East Plant 

EU011 – Potline Sweeping 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

C.1, C.4, 

C.5, C.7, 

C.9 

Opacity 20% Method 9 As Required by 

the Department Semiannual IN

Baghouse I & M (Append. K) Ongoing Semiannual IN

C.2, C.6, 

C.8, C.9 

Particulate 

Matter E = 55*P0.11 – 40 Method 5 As Required by 

the Department Semiannual IN

C.3, C.6, 

C.8. C.9 

Particulate 

Matter 0.02 gr/dscf Method 5 As Required by 

the Department Semiannual IN
D. EU015 – EU017 PASTE PLANT EMITTING UNITS WITH BAGHOUSES 

EU015 – Paste Plant Extruder EU016 – Paste Plant Mixer 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

D.2, D.5, 

D.6, D.11, 

D.13, D.15 

Opacity 40% 

Method 9 As Required by 

the Department Semiannual IN

Visual Survey Daily Semiannual IN

D.3, D.8, 

D.10, D.12, 

D.13, D.15 

Particulate 

Matter E = 55*P0.11 – 40 Method 5 As Required by 

the Department Semiannual IN

D.4, D.9, 

D.10, D.13, 

D.15 

Polycyclic 

Organic Matter 

(POM) 

None 

Operation of Dry Coke 

Scrubber: CFAC 

MACT Implementation 

Plan (Appendix F) 

Ongoing Annual 

Certification 

IN

Visual Survey Daily Semiannual IN

 EU017 – Pinhole Paste Drying 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

D.1, D.5, 

D.7, D.11, 

D.14, D.15 

Opacity 20% 

Method 9 As Required by 

the Department Semiannual IN

Baghouse I & M 

(Appendix K) Ongoing Semiannual IN

D.3, D.7, 

D.8, D.12, 

D.14, D.15 

Particulate 

Matter E = 55*P0.11 – 40 Method 5 As Required by 

the Department Semiannual IN

E. EU018 – PITCH STORAGE TANKS 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

E.1, E.2, 

E.3, E.4 Opacity 20% Method 9 As Required by 

the Department Semiannual IN 

F. EU019 – THERMINOL OIL HEATING SYSTEM 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting Requirements 

Compliance 

Method Frequency Status 

F.1, F.2, 

F.3, F.4 Opacity 40% Method 9 As Required by 

the Department Semiannual IN 

G. EU020 – EU023 PRIMARY SCRUBBER SYSTEM ALUMINA TRANSFER EU’S 

EU020 – East Plant Dry Scrubber Alumina Transfer (North) EU022 – West Plant Dry Scrubber Alumina Transfer (North) 

EU021 – East Plant Dry Scrubber Alumina Transfer (South) EU023 – West Plant Dry Scrubber Alumina Transfer (South) 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

G.1, G.3, 

G.4, G.6, 

G.8 

Opacity 20% 

Method 9 As Required by 

the Department Semiannual IN

Baghouse I & M 

(Append. K) Ongoing Semiannual IN

G.2, G.5, 

G.7, G.8 

Particulate 

Matter E = 55*P0.11 – 40 Method 5 As Required by 

the Department Semiannual IN
H. EU024 – EU033 PRIMARY GAS COLLECTION SYSTEM EMITTING UNITS 

EU024 – West Plant - Scrubber #1 EU029 – East Plant - Scrubber #6 

EU025 – West Plant - Scrubber #2 EU030 – East Plant - Scrubber #7 

EU026 – West Plant - Scrubber #3 EU031 – East Plant - Scrubber #8 

EU027 – West Plant - Scrubber #4 EU032 – East Plant - Scrubber #9 

EU028 – East Plant - Scrubber #5 EU033 – East Plant - Scrubber #10 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

H.1, H.4, 

H.5, H.9, 

H.12, H.13 

Opacity 20% Method 9 As Required by the 

Department Semiannual IN 

Visual Survey Daily 

H.2, H.6, 

H.8, H.10, 

H.12, H.13 

Total Fluoride 

(TF) 

1.3 kg/Mg (per 

Month) or Table 

C of Appendix G 

Method 13B or 

CFAC MACT 

Implementation Plan 

(Appendix F) 

Annual Quarterly IN 

H.3, H.7, 

H.8, H.11, 

H.12, H.13 

Polycyclic 

Organic 

Matter (POM) 

1.8 kg/Mg (per 

Quarter) or Table 

C of Appendix G 

Method 315 or 

CFAC MACT 

Implementation Plan 

(Appendix F) 

Annual Quarterly IN 

 

I. EU034 – EU038 POTLINE ROOF VENT EMITTING UNITS 

EU034 – Potline #1 Roof Vent – West Plant EU037 – Potline #4 Roof Vent – East Plant 

EU035 – Potline #2 Roof Vent – West Plant EU038 – Potline #5 Roof Vent – East Plant 

EU036 – Potline #3 Roof Vent – East Plant 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

I.1, I.4, I.5, 

I.8, I.9, I.12 Opacity 10% 

Method 9 (Appendix J) Quarterly 

Visual Surveys Quarterly IN

(Appendix J) Daily 

I.2, I.6, 

I.10, I.12 

Total Fluoride 

(TF) 

1.3 kg/Mg (per 

Month) or Table C 

of Appendix G 

Method 13B & Method 

14 (Appendix F) 

Three Test Runs 

per Month Quarterly OUT*

I.3, I.7, 

I.11, I.12 

Polycyclic 

Organic 

Matter (POM) 

1.8 kg/Mg (per 

Quarter) or Table 

C of Appendix G 

Method 315 & Method 

14 (Appendix F) 

One Test Run 

per Month Quarterly IN

*Violation Letter #VLRAG09-21 was issued for exceeding the fluoride emissions limit during July 2009. 

J. EU039 – EU043 CASTING FURNACE EMITTING UNITS 

EU039 – Casting Furnace #3 EU042 – Casting Furnace #7 

EU040 – Casting Furnace #4 EU043 – Casting Furnace #8 & #9 

EU041 – Casting Furnace #6 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

J.1, J.4, J.5, 

J.6 Opacity 40% Natural Gas or Liquid 

Petroleum Gas Combustion Ongoing Annual 

Certification IN

J.2, J.4, J.5, 

J.6 

Particulate 

Matter E = 0.882xH-0.1664 Natural Gas or Liquid 

Petroleum Gas Combustion Ongoing Annual 

Certification IN

J.3, J.4, J.5, 

J.6 Sulfur in Fuel 50 gr/100 cu ft Natural Gas or Liquid 

Petroleum Gas Combustion Ongoing Annual 

Certification IN
K. EU044 – EU048 CASTING PIT EMITTING UNITS 

EU044 – Casting Pit #3 EU047 – Casting Pit #8 & #9 

EU045 – Casting Pit #4 EU048 – Dross Handling 

EU046 – Casting Pit #6 & #7 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting Requirements 

Compliance 

Method Frequency Status 

K.1, K.3, 

K.5, K.7 Opacity 40% Method 9 As Required by 

the Department Semiannual IN

K.2, K.4, 

K.6, K.7 

Particulate 

Matter E = 4.10*P0.67 Method 5 As Required by 

the Department 

Annual 

Certification IN

L. EU049 – EU050 ALUMINUM SAW EMITTING UNITS 

EU049 – Sheet Ingot Saw EU050 – T-Ingot Saw 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

L.1, L.3, 

L.5, L.6 Opacity 20% Method 9 As Required by 

the Department Semiannual IN

L.2, L.4, 

L.5, L.6 

Particulate 

Matter E = 4.10*P0.67 Method 5 As Required by 

the Department Semiannual IN

M. EU051 – SANDBLASTING ACTIVITIES 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

M.1, M.4, 

M.7, M.9 Opacity 20% Method 9 As Required by 

the Department Semiannual IN

M.2, M.5, 

M.7, M.9 Opacity Reasonable 

Precautions Visual Surveys Weekly Semiannual IN

M.3, M.6, 

M.7, M.8, 

M.9 

Particulate 

Matter E = 4.10*P0.67 Normal Operations Annual 

Certification 

Annual 

Certification IN

N. EU052 – LECTROMELT FURNACE EMITTING UNIT 

Conditions Pollutant/ 

Parameter Permit Limit 

Compliance Demonstration Reporting 

Requirement

s 

Compliance 

Method Frequency Status 

N.1, N.3, 

N.4, N.6, N.8 Opacity 20% Method 9 As Required by 

the Department Semiannual IN

Baghouse I & M (Append. K) Ongoing Semiannual IN

N.2, N.4, 

N.5, N.7, N.8 

Particulate 

Matter E = 4.10*P0.67 Method 5 As Required by 

the Department Semiannual IN

O. EU053 – ROD MILL/MATERIAL STORAGE EMITTING UNIT 

Conditions Pollutant / 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

O.1, O.3, 

O.4, O.5, 

O.6, O.7 

Opacity 20% Method 9 As Required by 

the Department Semiannual IN

Baghouse I & M (Append. K) Ongoing Semiannual IN
O.2, O.3, 

O.4, O.5, 

O.6, O.7 

Particulate 

Matter E = 55*P0.11- 40 Method 5 As Required by 

the Department Semiannual IN

P. EU054 – EU062 NATURAL GAS BOILER EMITTING UNITS 

EU054 – Change House Boiler #1 EU059 – Paste Plant Boiler #1 

EU055 – Change House Boiler #2 EU060 – Paste Plant Boiler #2 

EU056 – Lab Boiler #1 EU061 – Warehouse Boiler #1 

EU057 – Machine Shop Boiler #1 EU062 – Warehouse Boiler #2 

EU058 – Machine Shop Boiler #2 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

P.1, P.4, P.5, 

P.6 Opacity 20% Natural Gas 

Combustion Ongoing Annual 

Certification IN

P.2, P.4, P.5, 

P.6 

Particulate 

Matter E = 1.026*H-0.233 Natural Gas 

Combustion Ongoing Annual 

Certification IN

P.3, P.4, P.5, 

P.6 

Sulfur in 

Fuel 50 gr/100 cu ft Natural Gas 

Combustion Ongoing Annual 

Certification IN

Q. EU063 – TRUCK, EQUIPMENT, AND HAUL ROAD EMISSIONS 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

Q.1, Q.3, 

Q.4, Q.5 Opacity 20% Method 9 As Required by 

the Department Semiannual IN

Q.2, Q.3, 

Q.4, Q.5 Opacity Reasonable 

Precautions 

Method 9 As Required by 

the Department Semiannual IN

Maintenance, 

Treatment, and Speed As Needed Semiannual IN

R. EU064 – GASOLINE STORAGE (TANK) EMITTING UNIT 

Conditions Pollutant/ 

Parameter Permit Limit Compliance Demonstration Reporting 

Requirements 

Compliance 

Method Frequency Status 

R.1, R.3, 

R.5, R.6 Opacity 20% Method 9 As Required by 

the Department Semiannual IN

R.2, R.4, R.6 Tanks Submerged Fill Certify Semiannual Semiannual IN

V. Inventory and Description of Regulated Emission Units and Processes: 

CFAC reports emissions of Fluoride and POM quarterly for compliance with the Primary Aluminum 

MACT standard. In July of 2008, plant production decreased as production ceased on 1.75 potlines. In 

February of 2009, plant production decreased again as production ceased on another 0.75 potlines. 

There was one potline operating until the end of October 2009, when plant production was completely 

curtailed. The world market for aluminum and the ability to negotiate a contract for electricity will 

dictate as to whether or not CFAC will resume production. The following table shows actual emissions 

from the facility. Note – Since, allowable emissions (Fluoride and POM) are calculated on a pound of 

emission per ton of aluminum-produced basis, determinations of allowable emissions are not available. 
Actual Emission Inventory Summary (TPY) 

Pollutant 

Permitted 

Actual 2009 

Emissions 

Actual 2008 

Emissions 

Particulate Matter 128.2 601.7 

PM10 42.5 222.8 

SO2 260.3 1007.8 

NOx 1.3 4.5 

CO 3292.5 14656.9 

VOC 35.0 155.6 

Fluoride 17.0 69.4 

POM 10.6 70.9 

VI. Recent Compliance History:

On March 12, 2009, the Department issued Warning Letter #WLRAG09-08 to CFAC for not 

maintaining and not operating emission controls in a manner consistent with good air pollution control 

practices for minimizing emissions while bypassing the exhaust gases past the emission control 

equipment. However, the Department made the determination not to pursue enforcement. 

Also, on November 19, 2009, the Department issued Violation Letter #VLRAG09-21 to CFAC for 

exceeding the permitted limit of 2.6 lbs of fluoride/ton of aluminum produced for Fluoride emissions in 

July 2009. This non-compliance issue is being reviewed by the Department to determine the 

appropriate response. 

VII. Compliance Monitoring Activities: 

During the reporting period, CFAC conducted maintenance at the facility in accordance with the 

Administrative Rules of Montana (ARM) 17.8.335 – Maintenance of Air Pollution Control Equipment 

for Existing Aluminum Plants. In September 2008 and September 2009, CFAC conducted maintenance 

and complied with the provisions of ARM 17.8.335. 

The Department most recently conducted an inspection on January 14, 2010. I arrived at 2:30 p.m. and 

met with Steve Wright, the Environmental Manager. Mr. Wright and I talked about the U.S. 

Environmental Protection Agency’s (EPA) green house gas reporting requirements and I was informed 

that CFAC produces perfluorocarbons in the crucibles holding the molten aluminum. Mr. Wright asked 

about emission factors and I suggested contacting the EPA. We talked about the recent curtailing of 

aluminum production at the facility and the possibility of CFAC restating someday. There were 

approximately 7 workers on site during the inspection. Mr. Wright said that it would take CFAC 

entering into an electricity contract and better worldwide aluminum prices before the facility could look 

at restarting. Mr. Wright stated that there were current negotiations regarding the electricity contract 

and that CFAC officials had been estimating the cost of a restart. The only emitting units that were still 

operating were some natural gas heaters that are used in conjunction with the water treatment at CFAC. 

 

Upon departure, I took two pictures of the parking area and the roofs (emitting units) at the facility (See 

Pictures #1 & #2). I noted no visible emissions from the facility during the latest inspection. During 
the inspection, the facility appeared to be in compliance with regard to visible emissions. The 

inspection ended at 4:00 p.m. 

VIII. Facility Compliance Report Review: 

The following table is a list of compliance reports the facility submitted during the review period. 

Report Title Date Due Date Received Date Reviewed 

Quarterly Report 1st Quarter 2008 May 15, 2008 Apr 11, 2008 Apr 21, 2008 

Maintenance Event Request for 9/08 Jul 26, 2008 Jul 23, 2008 Sept 2, 2008 

Periodic Startup, Shutdown & Malfunction Report 

January through June 2008 Jul 31, 2008 Jul 22, 2008 Jul 22, 2008 

Semiannual Report & Secondary MACT Requirements 

January through June 2008 Jul 31, 2008 Jul 22, 2008 Jul 22, 2008 

Quarterly Report 2nd Quarter 2008 Aug 15, 2008 Jul 17, 2008 Jul 22, 2008 

Fluoride & POM Emission Testing – Bison Engineering Nov 4, 2008 Nov 5, 2008 Dec 18, 2008 

Maintenance Event Report Nov 14, 2008 Oct 3, 2008 Oct 14, 2008 

Quarterly Report 3rd Quarter 2008 Nov 15, 2008 Oct 16, 2008 Oct 17, 2008 

Periodic Startup, Shutdown & Malfunction Report 

July through December 2008 Jan 31, 2009 Jan 12, 2009 Jan 27, 2009 

Semiannual Report & Secondary MACT Requirements 

July through December 2008 Jan 31, 2009 Jan 12, 2009 Jan 27, 2009 

Title V Annual Certification 2008 Jan 31, 2009 Jan 12, 2009 Feb 5, 2009 

Annual Emission Inventory Data Request Feb 15, 2009 Jan 14, 2009 Jan 23, 2009 

Quarterly Report 4th Quarter 2008 Feb 15, 2009 Jan 12, 2009 Jan 27, 2009 

Fluoride in Forage Report 2008 Mar 1, 2009 Feb 27, 2009 Mar 25, 2009 

Quarterly Report 1st Quarter 2009 May 15, 2009 Apr 16, 2009 Apr 20, 2009 

Maintenance Event Request for 9/09 NA Jul 17, 2009 Jul 30, 2009 

Periodic Startup, Shutdown & Malfunction Report 

January through June 2009 Jul 31, 2009 Jul 17, 2009 Jul 23, 2009 

Semiannual Report & Secondary MACT Requirements 

January through June 2009 Jul 31, 2009 Jul 17, 2009 Jul 23, 2009 

Quarterly Report 2nd Quarter 2009 Aug 15, 2009 Jul 13, 2009 Jul 14, 2009 

Maintenance Event Report Nov 9, 2009 Oct 2, 2009 Oct 15, 2009 

Quarterly Report 3rd Quarter 2009 Nov 15, 2009 Oct 9, 2009 Nov 13, 2009 

Fluoride & POM Emission Testing – Bison Engineering Dec 14, 2009 Nov 23, 2009 Dec 23, 2009 

Periodic Startup, Shutdown & Malfunction Report 

July through December 2009 Jan 31, 2010 Jan 14, 2010 Jan 26, 2010 

Semiannual Report & Secondary MACT Requirements 

July through December 2009 Jan 31, 2010 Jan 15, 2010 Jan 26, 2010 

Title V Annual Certification 2009 Jan 31, 2010 Jan 20, 2010 Jan 26 ,2010 

Quarterly Report 4th Quarter 2009 Feb 15, 2010 Jan 8, 2010 Jan 26, 2010 

Annual Emission Inventory Data Request Feb 15, 2010 Jan 20, 2010 Feb 3, 2010 

Fluoride in Forage Report 2009 Mar 1, 2010 Nov 23, 2009 Nov 25, 2009 

IX. Visible Emission Observation Information: 

During the inspection, no visible emission documentation took place. Since the facility was not 

operating, the visible emissions were well within the limitations of the permits. Also, when the facility 

was operating, CFAC completed observations of the potline roof vents on a daily basis and observed 

various control equipment vents weekly. 

X. Stack Test Review: 
CFAC conducts an ongoing stack test program. Testing for Fluoride and POM takes place monthly. 

Testing of the dry scrubbers takes place annually for Fluoride and POM. CFAC submits results of these 

tests quarterly. The following tables summarize the results. 

Summary of POM Results 

(All Values in Pounds of POM per Ton of Aluminum Produced) 

POM 

Date Actual Limit 

1st Qtr 2008 1.4 3.0* 

2nd Qtr 2008 1.9 3.0* 

3rd Qtr 2008 1.7 3.0* 

4th Qtr 2008 1.7 3.2* 

1st Qtr 2009 1.2 3.6 

2nd Qtr 2009 1.5 3.6 

3rd Qtr 2009 1.4 3.6 

4th Qtr 2009 1.3 3.6 

 *More restrictive limit with more potlines in production. 

Summary of Fluoride Results 

(All Values in Pounds of Fluoride per Ton of Aluminum Produced) 

Fluoride 

Date Actual Limit 

January 2008 1.1 2.5** 

February 2008 1.4 2.5** 

March 2008 1.6 2.5** 

April 2008 1.7 2.5** 

May 2008 2.1 2.5** 

June 2008 2.2 2.5** 

July 2008 1.9 2.5** 

August 2008 1.3 2.6 

September 2008 1.6 2.6 

October 2008 1.6 2.6 

November 2008 1.8 2.6 

December 2008 1.8 2.6 

January 2009 1.8 2.6 

February 2009 1.5 2.6 

March 2009 1.9 2.6 

April 2009 1.8 2.6 

May 2009 2.6 2.6 

June 2009 2.2 2.6 

July 2009 2.9# 2.6 

August 2009 1.9 2.6 

September 2009 2.3 2.6 

October 2009 2.1 2.6 

November 2009 NA 2.6 

December 2009 NA 2.6 

 **More restrictive limit with more potlines in production.

#

Exceedence of the limit. 
XI. Findings and Recommendations: 

During the reporting period on March 12, 2009, the Department issued Warning Letter #WLRAG09-08 

to CFAC for not maintaining and not operating emission controls in a manner consistent with good air 

pollution control practices for minimizing emissions while bypassing the exhaust gases past the 

emission control equipment. However, the Department made the determination not to pursue 

enforcement. 

Also, during the reporting period on November 19, 2009, the Department issued Violation Letter 

#VLRAG09-21 to CFAC for exceeding the permitted limit of 2.6 lbs of Fluoride/ton of Aluminum 

produced for Fluoride emissions in July 2009. Other than violation letter #VLRAG09-21, the 

Department believes CFAC is in compliance with the applicable requirements contained in CFAC’s air 

quality permits based upon: the information gathered at the time of the facility inspection; the 

observations made during the inspection; and the review of reports and compliance certifications 

submitted by CFAC during the review period. 
Picture #1. A picture from the entrance at CFAC showing the black roofs (emitting units). 

Picture #2. The relatively empty parking lot at CFAC.