| Abstract |
The 35-acre Nyanza Chemical site is a former dye manufacturing facility in Ashland, Middlesex County, Massachusetts. Land adjacent to the site is used for industrial, residential, commercial, and recreational purposes. The site overlies an unconsolidated glacial aquifer, which has been affected by site activities. Wastes included process wastewater, chemical sludge, solid process wastes in drums, solvent recovery distillation residue in drums, off-specification products, and un-recyclable process chemicals including phenol, nitrobenzene, and mercuric sulfate. The dye waste stream and wastewater were discharged to an onsite concrete 'vault' or settling basin adjacent to the main processing building. The ROD addresses management of migration as OU2, and constitutes an interim remedy designed to treat the highest ground water contamination and to collect additional data achieving cleanup objectives. A subsequent ROD will address uncontrolled wastewater discharges to the Sudbury River and its tributaries. The primary contaminants of concern affecting the ground water are VOCs including benzene, PCE, TCE, and toluene; other organics; and metals including arsenic, chromium, and lead. The selected interim remedial action for the site is included. |
