67 ] [ 68 ] Substances found, according to the reports, are naphthol , naphthalene , Sevin, tarry residues, alpha naphthol , mercury, organochlorines , chromium , copper , nickel , lead, hexachlorethane, Hexachlorobutadiene , pesticide HCH ( BHC ), volatile organic compounds and halo-organics. Many of these contaminants were also