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Putney, David

From: Mitchell, Kathryn M <Kathryn.Mitchell@alcoa.com>

Sent: Friday, June 06, 2014 8:05 PM

To: Putney, David

Cc: Bilskis, Patricia A.; Palazzolo, Michael A.

Subject: RE: FW: PM from paste plant at Intalco facility

Hi David, 

We have been actively looking into this, and, we do have some preliminary insights. First, it has become apparent that 

the fundamental underlying issue is that the Intalco Paste Plant Dry Coke Scrubber is steady state and our production is 

variable. Specially, Intalco has two parallel presses (A phase and B phase) that can run either simultaneously 

or independently. The first two source test runs were conducted during the operation of only one phase for the 

majority of time. The third run was conducted during full production (A phase and B phase operating 

simultaneously). Production in tons/hr for runs 1, 2, and 3 were 18.2, 11.9, and 30.8 respectively. 

Accordingly, if you look only at the third run, our result was 0.039 lbs PM/short ton anode produced. Although I’m 

uncertain about the exact statistics you intend to use to set the standard, if you average the best five source tests from 

all facilities plus two sigma, then the limit would be 0.050 lbs PM/short ton. 

So, although we haven’t fully vetted our collective thoughts on this, we are thinking about what it might look like to set a 

standard in the rule with the requirement for source testing to occur during full production (both presses running). 

We are also talking with the other facilities to assess if there is anything else especially different about the paste plant at 

Intalco from those found at the other primary aluminum reduction facilities. We are still collecting info and have 

planned a discussion to review this issue again internally on Tuesday. 

What is your current timeline for your next deadline and would you be available sometime to talk next Wednesday, June 

11th? 

Sincerely, 

Kathryn Mitchell 

Alcoa Intalco Works 

Environmental Manager 

360.961.6720 

From: Putney, David [mailto:putney.david@epa.gov] 

Sent: Friday, June 06, 2014 1:29 PM 

To: Mitchell, Kathryn M 

Subject: EXT: FW: PM from paste plant at Intalco facility 

Hello Kathryn, 
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Just got my electronic reminder again. Do you have any insights as to the cause of the higher PM emissions from 

the paste plant at the Intalco facility? Are these emissions untypically high (unrepresentative) for that source? 

Or, was the baghouse perhaps hampered by a bag leak at the time of the testing? 

Thanks, 

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.gov

From: Putney, David 

Sent: Friday, May 30, 2014 8:46 PM 

To: 'Mitchell, Kathryn M' 

Cc: Palazzolo, Michael A.; Bilskis, Patricia A. 

Subject: RE: PM from paste plant at Intalco facility 

Hello Kathryn, 

Just wanted to touch base on the paste plant PM testing (not trying to pester you, it’s just that the reminder 

popped up on my electronic calendar). Have you come across any historical test data (or maybe even more 

recent data) that suggests PM emissions from the paste plant at your facility are typically lower than the 0.092 

lb/ton anode that the 2013 ICR test data indicated? Or, did you maybe discover that something was “different” 

during the ICR test that renders those results unrepresentative of the normal paste plant operations? 

Thanks, 

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.gov

From: Mitchell, Kathryn M [mailto:Kathryn.Mitchell@alcoa.com] 

Sent: Friday, May 23, 2014 11:47 AM 

To: Putney, David; Bilskis, Patricia A. 

Cc: Palazzolo, Michael A. 

Subject: RE: PM from paste plant at Intalco facility 

Thanks David for the feedback. Good questions. Trish and I will pull some info together for you and circle back as 

soon as practicable. 

Meanwhile, can you provide us the grain loading for the other facilities you referenced? 
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Kathryn Mitchell 

From: Putney, David [mailto:putney.david@epa.gov] 

Sent: Friday, May 23, 2014 7:45 AM 

To: Bilskis, Patricia A. 

Cc: Mitchell, Kathryn M; Palazzolo, Michael A. 

Subject: EXT: PM from paste plant at Intalco facility 

Hello Patricia, 

I’ve been going over the 2013 testing ICR results with my contractor and the results for PM testing from 

the paste plant at the Intalco facility caught my eye. Specifically, the average PM emissions from your 

paste plant (i.e., 0.092 lb PM/ton anode) are about 2 1⁄2 times those of the next highest emitting paste

plant that was tested (i.e., 0.036 lb PM/ton anode, which was in turn more than twice the value of the 

next highest emitter). The practical implications of this situation is that it would appear (at this point, 

anyway) that the paste plant at the Intalco facility would not meet the MACT floor for PM (surrogate for 

metal HAP) without upgrades. 

So, I’m wondering if there is anything especially different about the paste plant at the Intalco facility 

from those found at the other primary aluminum reduction facilities. That is, are you aware of any 

specific reason(s) why the PM emissions from the paste plant at Intalco would be higher than those 

from the paste plants at the other facilities? For example, do the other facilities utilize membrane bags 

whereas Intalco does not? 

Of course, we (my contractor and I) could simply have an error in our math. That is to say, if you find a 

different value for average PM emissions from the paste plant at the Intalco facility (i.e., different than 

0.092 lb PM/ton anode) based on the testing done last year, then please point that out to me and we’ll

look at the situation again. Obviously I want to get the MACT floors correct in the upcoming 

supplemental proposal associated with the primary aluminum NESHAP RTR amendments. 

Thanks, 

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.gov