The Philadelphia - Camden - Wilmington metro area sits on the Delaware River, which has been lined with refineries and chemical plants for decades. The region has 18.5 million pounds a year of toxic releases, according to the EPA, with 7.2 million pounds discharged into the water. Superfund sites include the Franklin Slag Pile and the Martin Aaron site. Sperling Air Quality Index:
22 Sperling Water Quality Index:
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