Letter re: EPA/DEP WTC dust cleanup at 114 Liberty Street,

NYC 9/11 Public Portal Document

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For the reasons given above, EPA should acknowledge the fact that the elevated levels of asbestos foimd by the residents at 114 Liberty St. represents a health risk, although of uncertain exact numerical magnitude, as it demonstrates that asbestos is above backgroimd levels.

EPA/NYCDEP air sampling may not have been aggressive EPA/NYCDEP claimed in their 8/4/03 letter to FEMA that aggressive air testing was performed at 114 Liberty St.: Primarily, risk from asbestos is directly related to its concentration in air. Consequently, post-cleaning aggressive (i.e., use of a leaf blower and fans) air sampling was conducted at 114 Liberty St. by DEP’s contractors to insure that asbestos levels in air met regulatory-based and risk-based clearance criteria.

The EPA contractual Statement of Work'requires the following procedures for aggressive air sampling, namely directing a one-horsepower leaf blower at all surfaces: Before beginning aggressive air sampling, a 1 horsepower electric leaf blower shall be used to direct exhaust air against walls, ceilings, floors and other surfaces. This shall continue for at least five minutes per 1,000 square feet of floor. When directing the exhaust, caution shall be taken to minimize disturbance and potential damage to furnishings and personal belongings

At least one 20-inch fan shall be placed in the center of each room sampled. One fan per 10,000 cubic feet of room space shall be used. The fans shall be operated on slow speed and pointed toward the ceiling. The fans shall run for at least 15 minutes prior to the start of sampling. The fans shall operate continuously throughout sampling and shall not be turned off until sampling is completed.

Because there were still pockets of visible dust in the exposed steel framing of the walls and ceiling supports after the EPA/NYCDEP contractors allegedly conducted the aggressive sampling, it is highly unlikely that aggressive air sampling was actually performed. The visible pockets of dust would not have remained if a leaf blower actually had been directed at these surfaces.

EPA ignored silica over benchmarks after two abatements Tn their 8/4/03 letter to FEMA, EPA/NYCDEP claimed that all levels of tested contaminants at 114 Liberty St. were below health benchmarks: Sampling was done for the contaminants of potential concern following EPA protocols established specifically for EPA's WTC Residential Confirmation Cleaning Study. The analytical results were compared to health-based benchmarks established by EPA’s Interagency Indoor Air Task Force. The contaminants of potential concern included: asbestos, lead, dioxin, PAHs (Poly Aromatic Hydrocarbons), fibrous glass and crystalline silica.

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