Mendon – Longwood Ave

Site Investigation And Remediation Services

At the request of Mendon Truck Leasing, CORE performed a Phase II Environmental Site Investigation (ESI) and Supplemental ESI on the property to evaluate subsurface conditions in the area of the former dispenser island and underground storage tanks (USTs). The ESIs involved the installation of several soil borings and groundwater monitoring wells to delineate the horizontal and vertical extent of potential subsurface impacts. Subsurface soils were screened with a photoionization detector (PID) and soil and groundwater samples were collected for laboratory analysis. Impacts were noted primarily to groundwater in an isolated area in the northwestern portion of the Site. Due to the concentrations of gasoline-related compounds present, the New York State Department of Environmental Conservation (NYSDEC) requested that a remedial action be performed to accelerate the natural attenuation of those compounds. CORE reviewed options and recommended subsurface injections of PersulfOx, an in situ aerobic biodegradation enhancer and oxidizer. An In Situ Chemical Oxidation and Aerobic Biodegradation (ISCO) Work Plan was submitted for approval by NYSDEC. Upon approval, CORE completed the installation of five injection wells to 20 feet below ground surface and performed oversight of product injection. A Remedial Action Report (RAR) recommending Site/spill closure was submitted to the NYSDEC following two post-injection monitoring events. At the request of NYSDEC, two additional quarterly monitoring events were conducted to evaluate the effectiveness of the Remedial Action. NYSDEC approved spill closure for the Site on July 9, 2014. NYSDEC determined that decreasing VOC concentrations and the isolated, perched water table were not likely to have adverse effects on human health and the environment. CORE oversaw well decommissioning activities on Site between September 23 and September 29, 2014 during which time 17 groundwater monitoring and injection wells were decommissioned in compliance with Commissioner Policy-43 (CP-43). CORE submitted a Well Closure Letter to NYSDEC summarizing on-Site well abandonment activities on October 7, 2014. CORE provided Site investigation, remediation design, and remedial action oversight at the 1150 Longwood Avenue Site in Bronx, New York. CORE evaluated existing Site investigation data, developed and conducted Site-specific subsurface investigations, and evaluated data to determine the extent of migration of subsurface impacts to soil and groundwater.