(A variation of this article appeared in this morning's Union Leader. The below comes from Scientific American, and pinpoints the Merrimack River in NH, and the ADKs, hence my posting it here.)
http://www.sciam.com/article.cfm?chanId=sa003&articleId=EA19F960-E7F2-99DF-32460084B295C9EA
Tim
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The northeastern hot spots--which include the western Adirondacks and the middle and lower Merrimack River--share several characteristics: most can track much of their mercury deposition to local sources such as waste incinerators and coal-fired electricity plants.
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http://www.sciam.com/article.cfm?chanId=sa003&articleId=EA19F960-E7F2-99DF-32460084B295C9EA
Tim