The site is located in a suburban portion of Queens County. The site is a relatively flat lot. The site is approximately rectangular in shape and approximately 8 acres in area. The site is bordered to the north and west by the East River, to the south by 5th Ave., and to the east by a residential condominium complex. The surrounding land use is residential and city park land. Prior Site uses that have contributed to site contamination include unrestricted landfilling, and an abandoned car junkyard. Investigations were completed in 1997 and 2004, and a Remedial Action Work Plan was approved in June 2004. Remedial activities commenced on the site in Summer 2005. The majority of remedial activities have been completed as of January 2007. The Final Engineering Report and Site Management Plan are currently being drafted.
Site Environmental Assessment
Soil: The distribution of contaminated soil around the property is consistent with past activities such as the disposal of abandoned cars, scrap metal and drums. The three types of contaminants that have been identified in soils are PCBs, petroleum hydrocarbons (both volatile and semi-volatile) and metals. The PCBs are attributed to petroleum hydrocarbons from site spills and industrial sludge. The elevated levels of metals are also derived from industrial sludge. Other contamination constituents that have been detected in soils include PAHs, benzene, toluene and xylene. The largest individual area of contaminated soils was found along the east side of the property. This area is approximately 0.8 acres in size, and elevated levels of petroleum hydrocarbons have been detected at scattered locations from the surface to depths of over 12 feet. In this area intermittent accumulations of separate-phase hydrocarbons have been noted. Groundwater and soil gas: The entire site is built on a landfill of construction and demolition debris that was deposited in the East River. Groundwater at the site is predominantly saline (salt water). Some volatile organic compounds have been detected in groundwater consistent with the findings in soil. Soil gas sampling performed on the site revealed VOCs at two deeper locations (greater than 4 feet below grade) near the east property line in the petroleum contaminated area. Remediation of the site, which has been largely completed, includes the excavation and off-site disposal of contaminated soil from discrete locations (hot spots) that were identified during site investigations. Post-excavation sampling will be conducted to verify that site-specific cleanup goals have been attained. The remedy also includes engineering and institutional controls that are designed to prevent exposure to residual contamination and to protect the environment. Engineering and institutional controls include vapor barriers and active sub-slab depressurization systems which will be installed beneath each new building on the site; placement of two feet of clean soil (meeting NYSDEC Recommended Soil Cleanup Objectives) and a demarcation layer over all existing soils left in all open spaces and landscaped areas; placement of pavement or other impervious surfaces over all other areas. Finally, a Site Management Plan and Deed Restriction will be established to ensure that on-site soils are characterized and properly managed during future activities on the site.
Site Health Assessment
Soil and groundwater are contaminated with volatile and semi-volatile organic compounds and metals. Exposure to contaminated groundwater is unlikely since the area is served by public water. Access to the site is currently restricted by a fence minimizing the potential for exposures. Remediation of the site included excavation and removal of contaminated soil above site-specific cleanup levels; buildings and placement of clean soil in "landscaped areas" will minimize the potential for exposure to residually contaminated soil. Installation of vapor barriers and sub-slab depressurization systems beneath new construction will serve as a preventative measure to minimize the potential for exposure due to soil vapor intrusion.