EPA interim final report on WTC background study, April 2003

NYC 9/11 Public Portal Document

analytical results were evaluated and tabulated subsequent to validation and are presented in Tables 6-1 through 6-6. A detailed discussion of the results and development of background concentrations is provided in Section 6.0.

5.0 SAMPLING PROTOCOL DEVIATIONS The bulk samples collected were to be analyzed in the following order by the contracted laboratory: asbestos, lead, crystalline silica, calcite, gypsum and MMVF. Due to the backlog of asbestos samples at the EMSL, New York laboratory, the samples were shipped to the EMSL, New Jersey laboratory for the remaining analysis. In performing the analysis for the remaining parameters the laboratory used all of the material available therefore, the asbestos analysis was not performed on a majority of the bulk dust samples collected. This was done without notification to the EPA Project Officer.

Bulk dust samples were not collected from the common areas due to the absence of window air-conditioner units.

The following are deviations from the QAPP for each day of sampling.

August 20,2002 - Consent to sample was only obtained for one apartment and the basement laundiy room in this building. In the apartment, there was a power failure for two (2) minutes during sampling. Sampling time was increased by two (2) minutes to compensate for loss of volume.

August 21,2002 - Air samples could not be collected from the common area as there were no power outlets in the area. Counter wipes could not be collected due to lack of horizontal surfaces in the common area. Microvacuum samples could not be collected from the common area due to absence of porous surfaces.

August 22,2002 - Microvacuum samples could not be collected from the common area due to absence of porous surfaces. In one of the apartments, the pump used for the collection of crystalline silica, calcite and gypsum (SCG) failed. The sample collection was terminated at that time and the sample data reflected abbreviated sample duration.

August 29,2002 - There was a power failure of five (5) minutes on pump #3 being utilized for the SCG sample. The sampling time for SCO was increased by five (5) minutes to compensate for loss of volume. Microvacuum samples could not be collected from the common area due to absence of a porous surface. Air samples could not be collected from the common area as there was no power available in the area.

August 30,2002 - Microvacuum samples could not be collected from the common area due to absence of a porous surface. The ceiling wipe sample for asbestos could not be collected from one apartment due to acoustical texturing.

WORLD TRADE CENTER BACKGROUND STUDY 18

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