Planning for tougher air rules

Many companies are struggling with the need to design new facilities without knowing what air emissions control requirements will be applied retroactively. The Clean Air Act Amendments of 1990 require the US Environmental Protection Agency (EPA) to define Maximum Achievable Control Technology (MACT) for 189 hazardous air pollutants (HAPs). These technologies will be defined in groups over the next eights years. Once each technology is defined, existing plants will have three years to retrofit their facilities to meet the MACTs. Today, plants are being designed to meet current New Source Performance Standards (NSPS), which are potentially less stringent than MACT. MACT may require emission control facilities at plants to be retrofitted with more effective systems. While EPA has not determined MACT for all processes and for all HAPs, good engineering judgment can be used to anticipate which MACT may be required. This will vary by component and process. The severity of MACT requirements for different processes can be expected to fall between NSPS as a minimum and the current National Emissions Standard for Hazardous Air Pollutants (NESHAP) regulations as a maximum. One approach to predicting the expected MACT is to look at the major sources of air emissions in amore » plant.« less