Former Harrison MGP Site Remediation

History & Location

The Harrison Former MGP Site is located in Harrison, New Jersey. The site encompasses 32 acres. The site is bounded on the east by a roadway; the west by an Amtrak and PATH rail line; the south by the Passaic River; and the north by property owned by PATH. The site was acquired by PSEG and its predecessors from 1884 through 1924 and used for various operations including oil and manufactured gas storage. The MGP plant was constructed in 1924 and operated as a base load plant until 1963 when it was converted to a peak shaving status facility until retired from service in 1987. In 1992 the MGP was decommissioned. Buildings and structures were removed to grade. MGP foundations, pipes, and other remnants remained below grade. In 1998, PSEG began remedial work to define and address the extent of soil and groundwater contamination. Concurrent with ongoing studies and investigations, PSEG performed a variety of IRMs in 2004, 2009, 2010, 2012 and 2017. The site is currently used by PSEG for various operations. The site is planned for redevelopment. Sevenson’s contract, Phase 1 Gas Plant Remediation, was awarded on a competitive proposal basis. This project requires Sevenson to clear subsurface obstructions; pre-excavate soils and remove debris; perform ISS; install a hydraulic barrier wall; install a utility corridor; demolish site structures; and perform restoration activities.

Significant Project Features

• In-situ soil stabilization via deep soil mixing (auger) and shallow mixing with excavator.
• Pre-excavate 275,000 tons of soil/debris (concrete, timbers) to a depth of 7-ft. to create platform for ISS work.
• Clear obstructions down to depths of 25-ft. BGS to facilitate ISS work.
• ISS of 105,000 CY via deep auger mixing down to maximum depth of 45-ft. BGS.
• ISS of 315,000 CY via excavator down to a max depth of 40-ft. BGS.
• Process soils with reagent to comply with T+D facility requirements.
• Control odors and vapors using 300,000 gallons of RUSMAR odor suppressant foam (short and long term) and 60,000 gallons of SLSUPER odor neutralizing agent.
• Demolish existing site buildings and perform Hazardous Abatement.
• Dewatering for treatment via 200 GPM WWTP.
• Install 2,200 LF Hydraulic Barrier Wall (HBW) to depths down to 100-ft. BGS using DeWind One Passing Trencher.
• Jet grout termination at HBW interface/existing gas lines.
• Install utility corridor consisting of 16-in. and 36-in. gas lines.
• Restore 330,000 SF with 130,000 tons of clean import fill.

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