Municipal waste combustors in Massachusetts typically operate within the limits established by their Department of Environmental Protection (MassDEP) permits. On occasion, however, continuous monitoring systems or stack tests may record emissions that exceed these specified limits.

The 1998 Rule allows higher emissions for limited durations in specific circumstances: during startup or shutdown, in the event of certain malfunctions, or when there are isolated "spikes" in operating conditions. MassDEP may initiate enforcement action when a facility releases excess emissions not covered by these exceptions.

MassDEP may take enforcement action against municipal waste combustors when continuous monitoring or stack testing reveal excess emissions that:

  • Pose actual harm or a significant threat to public health or the environment; or
  • Indicate deficiencies in facility operations and/or maintenance; or
  • Suggest inadequacies in air pollution control equipment.

Depending on the circumstances of each case, MassDEP may:

  • Require the facility operator to test again or implement operational changes to ensure future compliance;
  • Issue the facility a Notice of Noncompliance (NON) that requires corrective action by a specified date; or
  • Order the facility to correct specific problems and possibly assess a financial penalty.

If an event is of very brief duration or emissions are barely above allowable limits, MassDEP will sometimes elect to take no further action.

When a facility demonstrates a chronic pattern of noncompliance or is found to be willfully violating the law, MassDEP has the option of referring the case to the Massachusetts Attorney General for civil litigation or criminal prosecution, or to the U.S. Environmental Protection Agency (EPA).  See the summary of MassDEP's Excess Emissions Policy  doc format of Excess Emissions Policy
for additional information.