ACID IMPAIRED LAKES AND PONDS

July 25, 2007

Letter from Margaret Foss, TMDL Coordinator for the New Hampshire Department of Environmental Services,

Hello everyone,

Dear Colleague,

We thought you might be interested to know that a draft Total Maximum Daily Load (TMDL) report for 156 acid impaired lakes and ponds and 2 impoundments (which includes 114 beaches) and 21 Aluminum impaired lakes is now available for public comment until the 4 pm on August 23rd, 2007. These surface waters are currently listed as impaired because of low pH and, in some cases, high aluminum, that violate New Hampshire surface water quality standards. Low pH can result in acidic conditions that can be harmful to fish and other aquatic life. Aluminum can also be harmful to aquatic life. The cause of the low pH is primarily attributable to atmospheric deposition of nitrogen oxides and sulfur dioxides (i.e., acid rain) emitted from sources such as fossil fuel plants to the west of New Hampshire. The aluminum violations are attributable to the low pH created by the acid rain which can transform and mobilize naturally occurring aluminum typically found in the soils. The purpose of the TMDL is to establish allowable pollutant loads that will result in attainment of water quality standards for pH and aluminum in these surface waters.

TMDLs are comprehensive water quality reports that are required for certain impaired waters in accordance with the federal Clean Water Act. The purpose of the TMDL is to determine the maximum pollutant load which a surface water can handle and still meet water quality standards and, to allocate the allowable load amongst the various pollutant sources. In accordance with federal regulations [40 CFR 130.7 (c) (ii)], calculations to establish TMDLs must be made available for public review. More general information regarding TMDLs is available at http://www.des.nh.gov/wmb/tmdl/

The draft TMDL may be viewed or downloaded at http://www.des.nh.gov/wmb/tmdl/draft_tmdl.html . Instructions for submitting comments are also available at http://www.des.nh.gov/wmb/tmdl/commentform.htm.

Following the public comment period and approval of the TMDL by the U.S. Environmental Protection Agency, a final TMDL and response to comments will be made available at http://www.des.state.nh.us/wmb/tmdl/nhstatus.htm.

Sincerely,

Margaret Foss
TMDL Coordinator
New Hampshire Department of Environmental Services,
Water Division, Watershed Management Bureau
29 Hazen Dr. P.O. Box 95
Concord, NH 03302
603 271-5448