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From: Curt Wells [mailto:cwells@aluminum.org] Sent: Thursday, April 02, 2015 3:09 PM To: Putney, David; Charles D. Johnson Subject: RE: Comments on Primary Aluminum NESHAP su pplemental proposal

David –

In answer to your second question below, please see the attached
matrix which details the status of PP and BF stack continuous particulate matter monitoring systems at Associatio n member facilities. As you will see, the matrix identifies 53 additional
stacks at member facilities that would need PM moni toring as these were not included in the 388 potline stacks noted i n the Association’s 2/6/15 comments as requiring monitori ng.

Please also note that the attached matrix does not include Century facilities as they are not members of the Associati on and are therefore outside the scope of your request.

As regards question #1, I look forward to talking w ith you regarding it next Wednesday 4/8 on the call already scheduled with Alcoa personnel.

Please let me know if you have any questions.

Thanks.

Curt.

From: Putney, David [mailto:putney.david@epa.gov] Sent: Friday, March 27, 2015 2:41 PM
To: Charles D. Johnson
Cc: Curt Wells Subject: Comments on Primary Aluminum NESHAP supple mental proposal

Chuck,

I was recently analyzing some of the comments submi tted by The Aluminum Association (dated 02/06/15) in response t o the supplemental proposal for RTR amendments to the NESHAP for Prima ry Aluminum Reduction Plants (published 12/08/14) and have come across two items for which I am soliciting additional information fr om you.

First, I am requesting additional information conce rning the
additional anode bake furnace emissions data and re vised MACT floor for PM emissions from anode bake furnaces, as menti oned in Issue #5 “Errors in the Existing Anode Bake Furnace PM Limit Calculation” (found on pages 5 through 7 of your comments dated 02/06/15). After correcting the anode bake furnace emissions used in the supplemental proposal for the Alcoa-Warrick and Century Aluminum -Sebree facilitiesp. 2 of 2

and including the additional emissions data provide d, it appears that the MACT floor pool would now include the Massena W est, Wenatchee, Warrick, Alumax and Sebree facilities. That is, it would appear that our analyses of the new data differ in that we woul d include the anode bake furnace at the Sebree facility in the MA CT floor pool whereas you include the anode bake furnace at the I ntalco facility. Please explain why you included the anode bake furn ace at the Intalco facility (with average emissions, including the add itional data, of 0.273 lb PM/ton anode) in the MACT floor pool inste ad of the anode bake furnace at the Sebree facility (with average e missions, after correcting the data used initially, of 0.112 lb PM/ ton anode). In an effort to not request duplicate effort from industr y I would point out that I also posed this question to Alcoa, Inc. staff who had
submitted a similar comment – The Aluminum Associat ion may want to consider a coordinated response with Alcoa to this question.

Second, I am requesting additional information conc erning the current monitoring of PM emissions from baghouses installed on anode bake furnaces or paste production plants, as mentioned i n Issue #14 “Installation of Continuous Bag Leak Detection Syst ems” (found on pages 17 through 20 of your comments dated 02/06/15 ). Specifically, in paragraph 4 on page 19 you imply that the baghou ses associated with anode bake furnaces and paste production plant s at primary aluminum production facilities would need to be equ ipped with bag leak detection systems (BLDS) or particulate matter continuous emissions monitoring systems (PM CEMS) in order to comply with the proposed revisions to the Primary Aluminum NESHAP. I was under the impression that most, if not all, of the baghouses associated with existing anode bake furnaces and paste production p lants at primary aluminum production facilities were already equippe d with either BLDS or PM CEMS. Would you please poll the facilities in your association and provide me information on how many of the bagho uses associated with existing anode bake furnaces and paste product ion plants at primary aluminum production facilities are not alre ady equipped with
either BLDS or PM CEMS?

Thanks so much for your assistance in these matters

.

David Putney, Environmental Engineer U.S. Environmental Protection Agency Office of Air Quality Planning and Standards Sector Policies and Programs Division 109 T.W. Alexander Drive, RTP, NC 27711 Mail Drop D243-02 Ph: (919) 541-2016 Fax: (919) 541-3207 Email: putney.david@epa.govAluminum Association Member Primary Plant PP and BF stack survey 4/2/2015

Location # of PP Stacks # Equipped with BLD's # BF Stacks # Equipped with BLDs

Massena 1 1 1 1
Warrick 1 1 7 7
Wenatchee 1 0 16 0
Intalco 1 0 1 0
New Madrid* 1 0 33 0

Total 5 2 58 8

Total # of stacks without BLD's 53

* N ew Madrid has 3 bake furnaces. Bake furnaces 1 and 2 are controlled by 4 scrubbers that have 4

m odules each. Each module has 4 stacks but a BLD on one of the 4 stacks in the module would detect a leak anywhere in that module so 32 BLD's would be needed for bake furnaces 1 and 2 (2 x 4 x 4). Bake furnace 3 has all modules ducted to a common stack so 1 BLD would be needed for it resulting in the need
for 33 total.