Northeast Regional Mercury Total Maximum Daily Load

Elevated levels of mercury in freshwater fish have been a concern in the Northeast states (Connecticut, Maine, Massachusetts, New Hampshire, New York, Rhode Island, and Vermont) for many years. All of the states have fish consumption advisories that recommend their residents limit the amount of fish they consume from the states’ waters. Over the past decade, these states have made tremendous progress in reducing mercury from in-region sources. Between 1998 and 2003, in-region mercury emissions decreased by approximately 70 percent. However, fish mercury levels remain high because a significant portion of mercury deposited in the region originates from sources outside of the region. Due to the need for greater mercury reductions to eliminate fish consumption advisories, the Northeast states and the New England Interstate Water Pollution Control Commission embarked on the development of the first ever multi-state Total Maximum Daily Load (TMDL) for mercury-impaired waters. Modeled closely after the Minnesota Statewide Mercury TMDL, the Northeast Regional Mercury TMDL uses 1998 as a baseline year and states that fish tissue concentrations must be reduced by 74 to 91 percent from 1998 levels to meet fish tissue goals in each of the states. To meet this goal, anthropogenic atmospheric deposition of mercury must be reduced by 98 percent from all sources. The TMDL outlines the necessary reductions from in-region and out-of-region sources and recommends that more stringent federal controls are placed on coal-fired power plants and other mercury sources. A three-phase implementation plan is proposed for both in-region and out-of-region sources. The draft TMDL was released for public comment on April 11, 2007. Taking into consideration comments received, the TMDL was revised and the final version was submitted to EPA on October 23, 2007. On December 20, 2007, the final TMDL was approved by EPA Regions 1 and 2