The week of November 14th, 2011, the BSGE community was informed that there was a presence of two chlorinated solvents, tetrachloroethene (PCE) and trichloroethene (TCE) in the soil vapors underneath BSGE’s foundation.
The level of each of the chemicals has always been well below the New York State Department of Health Air Guideline Values (NYSDOH AGV’s) but when testing was first done in 2008, the levels were above the routine background levels found in the average New York State home.
The New York City School Construction Authority (SCA) has been aware of these chemicals when it first did environmental testing on the air quality in the BSGE building and soil underneath it in 2008 as a result of routine procedures it follows when leasing a building. At that time, the NYSDOH was informed but the BSGE community was not. A School Construction Authority representative stated that because the levels of the chemicals were below the AGV’s and because the SCA was involved in a lawsuit with the landlord that the school community was not informed until recently.
One of the chemicals found, PCE is a chemical routinely used in dry cleaning, and the other, TCE is an industrial chemical used for degreasing. The source of the contamination under the building is most likely not directly underneath the BSGE building and is most likely migrating from an off site location, probably a nearby dry cleaner.
The week of November 14th, Ms. Johnson sent home a letter explaining the situation to BSGE families and invited them to a presentation and question and answer period on the night of November 23rd by the SCA at BSGE.
One of the short term actions taken by the SCA to ensure that no vapors would contaminate the air in the BSGE building was to fill any holes in the foundation. The recommended long term action is to build a “subslab depressurization system” which would ventilate any vapors from under the building out of the building through the roof.
The building was tested twice in 2009 and again in 2011 and the results have consistently been below the state’s AGV’s. According to the SCA representative, “the AGV’s are health based criteria which were developed based on an exposure scenario of all day, every day, for an entire lifetime.”
Soil contamination is common in New York City because most of the city’s land has been inhabited for a long time and had many different uses especially in Long Island City/Astoria which has a lot of warehouses, factories, and industrial spaces.
In addition to the environmental issues discuss, the SCA presented other issues related to the future maintenance and renovations on the BSGE building.
Independent testing done on 11/22/2011 confirmed the SCA’s findings about the air quality.
An additional test will be done over winter recess 2012 to confirm previous indoor air quality findings.