January 30, 2015

Memorandum

Subject: Summary of Conference Call with Alcoa Repr esentative

From: David Green, RTI

To: David Putney, EPA/OAQPS

I. Purpose

The purpose of the call was to discuss provisions of the Primary Aluminum Risk and Technology Review Supplemental Proposal related to the proposed particulate matter (PM) limit for anode bake furnaces, bag leak detection requirement s, and work practices.

II. Date and Time

The call was held January 29, 2015 between 1:00 p. m. and 1:45 p.m.

III. Attendees

David Putney, EPA/OAQPS David Green, RTI Mike Palazzolo, Alcoa

IV. Summary

A. Proposed PM Limit for Anode Bake Furnaces

Mike Palazzolo stated that based on newly conducted PM tests using EPA Method 315 some of the anode bake furnaces, including some of those in the MACT floor pool, would not meet the proposed emission limit that was derived from repor ts of PM testing conducted in 2013. Mr. Palazzolo agreed to provide summaries of data submi tted to EPA in 2011, as well as data from tests conducted in 2014 and requested that all of these d ata be used to determine, and if necessary, revise the PM standard for anode bake furnaces. No changes have been made to the furnaces or the control systems since 2011.

Additionally Mr. Palazzolo stated that the 2013 ano de bake furnace PM emission data obtained from a test of three baghouses at Warrick was misin terpreted in that there were only three tests, with two of the tests each consisting of 3 runs on diffe rent stacks from two baghouses. EPA had interpreted the test report on the basis of 6 tests having been conducted.

B. Bag Leak Detection System Requirements

Mr. Palazzolo stated that in contrast to most affec ted sources, three of the older potlines at the Warrick plant each had 36 separate exhaust stacks ( see Attachment 1) and that the cost of installing and operating Bag Leak Detection Systems on each in dividual stack would be prohibitive, based onp. 2 of 4

vendor quotes. He suggested that the current NESHAP requirements for visible emission monitoring might be justified for potline stacks, and planned to provide cost information as part of his written comments on the proposal.

C. Proposed Work Practices for Potlines

Mr. Palazzolo stated that the proposed work practic es in 40 CFR §63.854(a), particularly requirements to reseal pot crusts that have been br oken, as often and as soon as practicable, and to reduce cell temperatures to as low as practicable m ay not be optimal for minimizing emissions. He suggested alternative work practices, taken from th e preamble for 40 CFR Part 60, Subpart S i.e., the Standards of Performance for Primary Aluminum Reduc tion Plants (see Attachment 2).p. 3 of 4

Attachment 1. Alcoa Warrick Potline Stacks.p. 4 of 4

Attachment 2. Alternate Work Practices for Potlines Suggested by Alcoa, based on New Source

Performance Standards. a

1. Hood covers should fit properly and be in good r epair;

2. If the exhaust system is equipped with an adjust able air damper system, the hood exhaust rate for individual pots should be increased whenever hood c overs are removed from a pot (the exhaust system should not, however, be overloaded by placin g too many pots on high exhaust);

3. Hood covers should be replaced as soon as possib le after each potroom operation;

4. Dust entrainment should be minimized during mate rials handling operations and sweeping of the working aisles;

5. Only tapping crucibles with functional aspirator air return systems (for returning gases under the collection hooding) should be used; and

6. The primary control system should be regularly i nspected and properly maintained.

a See 45FR44203 – 44204, June 30, 1980