Stanhope, New Jersey

Soil, Groundwater, and Surface Water Remediation at Isolatek/U.S. Minerals Site


This site is currently owned by United States Mineral Products Company (USM), which acquired the various parcels of the property over the years starting in 1929. However, operations began at the site in 1875 when they leased the property from Musconetcong Iron Works and continued until 1989. The original operations consisted of mineral wool production, achieved by melting iron slag in cupolas then spinning it into fibers using spinning wheels or jets of air or steam. The waste material was used to fill much of the site, including the permitted landfill.

For a 20-year period—1952 through 1972—operations also included production of mineral fiber batts. This process involved applying a phenolic resin to the fiber and asphalt in order to bind a layer of paper or foil to the mineral wool. 

Prior to the sale of the property, First Environment was retained by USM to conduct a Preliminary Assessment (PA) and subsequent site investigation activities at their facility in Stanhope, New Jersey. The PA identified more than 40 Areas of Concern (AOCs).

Some of the AOCs required additional investigation, including the 10,000-gallon asphalt aboveground storage tank (AST)/phenol AST, 10,000-gallon kerosene AST, 10,000-gallon No. 2 fuel oil AST, 10,000-gallon fuel oil underground storage tank (UST), two USTs of unknown size and contents, underground pump house, bead trap, former maintenance drum storage area, storm sewer collection system, USM building leachfield, research and design building leachfield, dry well, site-wide fill material, four of the current or historic transformers, and several spill areas.

Notably, on November 26, 2007, a release of approximately 3,000 gallons of No. 2 Fuel Oil occurred at the adjacent Royal Oil Facility. The oil entered the USM site from the southern property boundary through a tributary to the Musconetcong River. NJDEP and County Hazardous Material Response Teams conducted spill response activities within the tributary and in the river.

First Environment is currently conducting additional soil, groundwater, and sediment delineation activities across the site and within the Musconetcong River.