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GACT / MACT / NESHAP / NSPS Information
Under the Clean Air Act, the USEPA is required to develop standards for industrial categories of "major" sources of hazardous air pollutants (HAPs) that require the application of maximum achievable control technology (MACT). Section 112(g) requires a "case-by-case MACT determination" by the Air Quality Division if a major source is constructed or reconstructed before the USEPA issues a MACT regulation for that particular source category. Section 112(j), commonly referred to as the "MACT hammer," requires a case-by-case MACT determination if USEPA fails to promulgate a standard within 18 months after the scheduled date.
Maximum Achievable Control Technology (MACT)
Standards Promulgation Status
The following tracking tables are available through the USEPA Air Toxics Web Site.
- Background Information Document
- Closely Related Rules, Policies, or Program Guidance
- Compliance and Enforcement Information
- Example Notices & Reports
- FACT Sheets
- Implementation Tools
- Outreach & Training Materials
- Permitting Information
- Proposed & Promulgated Rules
- Questions & Answers
- Risk Assessment Information
- Source Identification & Location Information
Section 112(g) MACT Determinations
Case-by-case MACT Determinations pursuant to EGLE Rule 902(1)(h) / Federal Clean Air Act Section 112(g).
* If there are any Notices of Proposed Section 112(g) MACT Approvals, you will find them on the NSR Public Notice Documents page.