Maximum Achievable Control Technology (MACT)

Overview of MACT Compliance

Maximum Achievable Control Technology (MACT) standards are a critical part of the Clean Air Act Amendments of 1990 and part of the National Emissions Standards for Hazardous Air Pollutants (NESHAP). These federal regulations reduce toxic air emission by requiring the use of best-performing control technologies across industry sectors. MACT ensures facilities implement both technological and work practice controls to achieve the maximum achievable emission reduction, ultimately protecting public health and the environment from harmful impacts of hazardous air pollutants (HAP).

Who Is Subjected to MACT Compliance?

Facilities classified as major sources of HAP emissions must comply with MACT standards:

• • Emit more than 10 tons/year of single HAP
  • Emit more than 25 tons/year of a combination of HAP

Some area sources may also be subjected to MACT standards, though generally under less stringent requirements or Generally Available Control Technologies (GACT). For detailed classifications, refer to the Department of Environmental Protection Area Source MACT guidelines.

How Are MACT Standards Developed?

MACT standards are developed through a structured three-step process:

1. 1. Establish the MACT Floor
      1. Existing sources with more than 30 facilities: Takes the average of best-performing 12%
      2. Fewer than 30 facilities: Takes the average top 5 performers
      3. New sources: Utilize similar sources as best-controlled standards
   2. Evaluating Beyond-the-Floor Controls
      1. Considerations include cost, non-air quality health and environmental impacts, and energy requirements.
      2. Technologies may involve process changes, material substitution, enclosure systems, capture and treatment systems, design and operational standards.
   3. Establish MACT Standard Requirements
      1. Numerical emission limits for each HAP pollutant (tons/year)
      2. Production ratios
      3. Concentration limits
      4. Performance standard based on expected MACT in reducing HAP emissions
      5. Work practice standards

Compliance reports are submitted to EPA within 60 days of effective date for database inclusion and ongoing compliance MACT compliance verification.

MACT Compliance Key Timelines

Facilities are responsible for submitting the following MACT compliance reports and documentations in accordance with federal deadlines:

• • Initial Notification – Within 120 days of startup
  • Performance Test Notice – 60 days before test
  • Notification of Compliance Status (NOCS) – Submitted to EPA 90 days after initial compliance
  • Performance Test Reports – Full reports submitted within 60 days after testing
  • Startup/Shutdown/Malfunction Reports – 2 days prior to event with follow-up letter 7 days after
  • Semi-Annual Compliance Reports – Often 60 days after semiannual period ends

Staying Ahead of MACT Compliance

Maintaining compliance is an ongoing responsibility that may include regular state inspections and occasional EPA inspections involving personnel interviews, document and record reviews, evaluation of leak detection practices, or equipment and emission point check. With support from SEC experts, your facility can stay ahead of compliance issues and navigate all MACT standards with ease.