EPA Elects Not to Amend Four Air Toxics Rules
EPA finalized its decision not to amend four air toxics rules (also known as MACT standards) covering eight types of production processes. The agency concluded that the existing MACT (or Maximum Achievable Control Technology) standards effectively address air toxic emissions for all eight industries and that no additional controls are necessary.
Within eight years of setting the MACT standards, Clean Air Act section 112(f) directs EPA to assess the remaining health risks from each source category to determine whether the MACT standards protect public health with an ample margin of safety and protect against adverse environmental effects. This is a "risk-based" approach called residual risk. Here, EPA must determine whether more health-protective standards are necessary.
EPA's recent residual risk assessment found that after application of the MACT standards the chronic cancer risks are below 1-in-1 million, and no further cancer risk reduction is required. The analysis also found that non-cancer and acute risks to humans, as well as ecological risks from these facilities are low and that no further controls are warranted. Also, every eight years after setting the MACT standards, Clean Air Act section 112 (d)(6) requires that EPA review and revise the standards, if necessary, to account for improvements in air pollution controls and/or prevention. The technology assessment did not identify any advancements in practices, processes, or control technology.
The final rule affects the following rules/standards, with their issue dates noted in parentheses, followed by the affected source categories:
- Group I Polymers and Resins (09/05/96) which includes the following production processes: Polysulfide Rubber Production, Ethylene Propylene Rubber Production, Butyl Rubber Production, and Neoprene Production;
- Epoxy Resins Production and Non-nylon Polyamides Production (03/08/95) which includes the following production processes: Epoxy Resins Production and Non-nylon Polyamides Production;
- Generic Maximum Achievable Control Technology (06/29/99): Acetal Resins Production; and
- Generic Maximum Achievable Control Technology (06/29/99): Hydrogen Fluoride Production.
The full EPA notice is available at www.epa.gov/ttn/oarpg/t3pfpr.html.