HILLSDALE, N.J.—A two-story office building built on the site of a former dry cleaner at 137 Broadway was knocked down recently as the first step in a long-term site remediation plan put into motion by the State Department of Environmental Protection.
“It’s PCE (perchlorethylene) contamination in shallow ground water underneath the site that’s slowly moving in the direction of a nearby bank,” DEP spokesperson Larry Hajna said Oct. 25.
Of the site of Alexander Cleaners from the late 1960s to 1996, Hajna previously said demolition and site remediation was part of a DEP plan to prevent future off-site environmental contamination.
The DEP considers PCE a potential carcinogen, and it is regulated as a hazardous substance, Hajna said. He said in July 2018 that the chemicals migrating beneath the former dry cleaner were not yet a public health concern but could not provide a status report by press time.
Hajna said the demolition and cleanup will initially be funded via a publicly funded cleanup supervised by NJDEP, with likely future actions against identified responsible parties.
According to NJDEP’s July 2018 “decision document” laying out a cleanup strategy, the first step is to demolish the existing structure to allow access to the “PCE source area or hotspot” to complete excavation using large augers.
“Upon completion of the demolition, further source area characterization, delineation and soil excavation activities will be performed,” notes the cleanup plan.
Soil will be excavated to a depth of 28 feet, followed by additional testing, and backfilled with flowable fill “such as a cement-like slurry” said NJDEP.
“Upon completion of soil excavation, the area will be backfilled to match existing site grade using certified clean fill. The area will then be paved with asphalt. Additionally, post-remediation groundwater monitoring will be implemented,” notes NJDEP’s decision document.
The demolished two-story structure was an unoccupied office building recently though a real-estate firm occupied one floor until September 2017.
Previously the building was retrofitted with a vapor-mitigation system in 2002 and basement walls were sealed in 2004 in efforts to address PCE soil contamination beneath the building, Hajna noted.
Borough Engineer Chris Statile said the cleanup is an NJDEP-run program on private property. He said DEP officials made a presentation to Hillsdale Borough Council last summer to provide an update on the proposed cleanup plan. Statile said he anticipated the NJDEP cleanup process to be a multi-year effort.
In July 2018, NJDEP estimated implementation of its remedial action plan to cost $1,880,059, which included groundwater monitoring.