When a magnet high school in Cambria Heights, Queens, closed last month because of a mercury spill, 2,500 students had to be bused to other neighborhoods. The accident made splashy headlines and then slipped off the radar. But what are the long-term effects of a spill like that, and what happens when the spills of yore continue to pollute the soil, air and groundwater of today? The New York State Department of Environmental Conservation walked us through five sites (out of fortysomething) that continue to pose a “significant” threat to the public health.

Greenpoint Petroleum Remediation Project: Behold the grandpappy of local chemical spills: Since the 1900s, more than 17 million gallons of petroleum and other pollutants have been seeping into the air, soil, groundwater and surface water of Newtown Creek from area refineries and storage facilities. More than 9.5 million gallons have been recovered, but the DEC says the ongoing release still threatens area residents and aquatic life. The DEC, along with the New York Attorney General’s office, is currently seeking faster cleanup of the floating petroleum and contaminated groundwater.

West Side Corporation Site: Five 10,000-gallon ground storage tanks were used at this 4.5-acre Jamaica, Queens, property for tetrachloroethylene, a chemical used for dry cleaning and metal degreasing. The tanks were removed in 1992, but a plume of PCE-contaminated groundwater has traveled beyond the site. Says DEC spokesperson Maureen Wren, “We’ve done a lot here—including involving the community because of the contaminations’ impacts.” The lot now serves as a bus depot, used for the storage, service and dispatch of school buses.

Hexagon Laboratories: Wedged between industrial and residential buildings in the Northeast Bronx, Hexagon manufactured organic chemicals and pharmaceuticals from the 1940s through 1989. Tanks were used for the storage of hazardous wastes (toluene, xylene, etc.). Asbestos was present, and in 1990 the NYPD Bomb Squad removed explosives, water-reactive metals, poisons and compressed-gas cylinders from the location. In 1993, the DEC placed it on the Superfund Registry. Soil and groundwater cleanup efforts are still under way.

Whole Foods: At Third Avenue and 3rd Street (directly across from where Whole Foods plans to build its ’08 Brooklyn outpost) sits a lot that was used as a fuel station till the late 1990s. The site endured several oil spills; now, high levels of benzene—a potentially carcinogenic gasoline by-product—have seeped into the soil around it. While the toxins don’t present an immediate threat, thousands of tons of petroleum-contaminated soil have been removed since March 2005.

Arthur Kill Generating Station: On September 7, 1998, a transformer at this 15-acre facility leaked 2,200 gallons of fluid—including transformer oil, trichlorobenzene and PCBs—into nearby wetlands and the Arthur Kill waterway. Con Edison tried repeatedly to remove the contaminated soils, concrete and asphalt, and has also agreed to pay millions to exposed firefighters and emergency workers.

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