Proposed Revisions to Chapter 101: Visible Emissions Regulation

The Maine Department of Environmental Protection (DEP) is proposing changes to Chapter 101: Visible Emissions Regulation. Chapter 101 regulates opacity limits for fuel burning equipment, process, and fugitive emission sources. Currently, a certain number of opacity limit exceedances are allowed for these sources over a specified time average within a certain period of time. For […]

The Maine Department of Environmental Protection (DEP) is proposing changes to Chapter 101: Visible Emissions Regulation. Chapter 101 regulates opacity limits for fuel burning equipment, process, and fugitive emission sources.

Currently, a certain number of opacity limit exceedances are allowed for these sources over a specified time average within a certain period of time.

For example, the current opacity limit for boilers firing #2 fuel oil is: “Visible emissions from any unit firing #2 fuel oil shall not exceed an opacity of 20 percent on a six-minute block average basis, except for no more than one six-minute block average in a 3-hour period.” This proposed regulation would eliminate the underlined exception.

For some sources (i.e. boilers firing #4, #5, and #6 fuel oil; stationary internal combustion engines and boilers firing wood waste/biomass) the exceptions are replaced with the option to comply with four specific work practice standards during periods of startup, shutdown, or malfunctions. These proposed work practice standards for fuel burning equipment include:

1) Maintaining a written or electronic log of the date, time and duration of exceedances from the units (sources and air pollution controls) that took place during these periods;

2) Developing and implementing a written startup and shutdown plan;

3) Limiting the duration of unit startups, shutdowns, or malfunctions to not exceed one hour per occurrence; and

4) At all times operating the unit and associated air pollution control equipment in a manner consistent with safety and good air pollution control practices for minimizing emissions.

Other proposed changes include defining the types of fuel by ASTM standards and emission limits for units discharging into a combined stack. The entire list of Maine DEP’s proposed changes can be found on their website.

Comments for these proposed revisions were already accepted by the Maine DEP. If you would like assistance determining how these proposed changes may affect your facility, please contact Mike Rioux at 207-591-7000 x13.