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Question & Answer for Requesting and Making Impracticability Determinations for Group 1 Furnaces

The purpose of this Question and Answer (Q&A) document is to provide an answer to an inquiry EPA received on how to streamline the process of requesting and making impracticability determinations for “group 1 furnaces” under 40 CFR, part 63, subpart RRR: National Emission Standards for Hazardous Air Pollutants for Secondary Aluminum Production. The EPA is posting a response to this inquiry to ensure a timely review of these requests and the associated determinations. 

Also included are the historical correspondence letters between Kaiser Aluminum and EPA Region 10.

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