Letter to Congress regarding EPA and DEP WTC dust clean-up

NYC 9/11 Public Portal Document

0.0009 s/cc. No additional cleaning is required for asbestos. AU of the areas met the primary clearance level for asbestos'.

Lead - Thirty pre-cleaning wipe samples were collected and analyzed for lead at a detection limit of 20 lig/fl?. Thirteen samples were above 25 /ig/tf and represent apartments on the 10* floor (2 of 3 above 25 gg/tf), 9* floor (2 of 3 above 25 ;ig/ft^), 7* floor (1 of 3 above 25 /ig/ft^), 5* floor (2 of 3 above 25 /ig/tf), 4* floor (2 of 3 above 25 gg/ft^), 3"* floor (1 of 3 above 25 gg/ft^), and 11* floor (3 of 6 above 25

Thirty post-first cleaning wipe samples were collected fi-om each floor and analyzed for lead at a detection limit of 9 All of the sample results were below 25 Post-cleaning concentrations from areas that had pre-cleaning concentrations above 25 were all below the primary clearance value. No additional cleaning required for lead. AU of the areas met the primary clearance level for lead.

Dioxin - Thirty pre-cleaning wipe samples collected and analyzed for dioxin. The maximum Toxicity Equivalents (TEQ) Estimated Maximum Potential Concentration (EMPC) with non-detects equal to of the detection limit (ND=l/2) value was 0.951 ng/m^. This sample and the remaining 29 samples were all below the primary clearance value of 4 ng/m^. Based on the pre-cleaning samples, no additional cleaning required for dioxin.

Thirty post-cleaning wipe samples collected and analyzed for dioxin. The maximum TEQ EMPC (ND=l/2) value was 0.837 ng/m^. This sample and the remaining 29 samples were all below the primary clearance value of 4 ng/m^. Based on the post-cleaning samples, no additional cleaning required for dioxin. AU of the areas met the primary clearance level for dioxin.

PAHs - Thirty pre-cleaning wipe samples collected and analyzed for PAHs at a detection limit of 1 pg. All or the results were below the detection limit and the calculated Toxicity Equivalent Factors (TEFs) for each sample was 116 ng/ra^, which is below the primary clearance level of 300 Based on the pre­ cleaning samples, no additional cleaning is required for PAHs.

Thirty post-cleaning wipe samples collected and analyzed for PAHs at a detection limit of 1 gg. All or the results were below the detection limit and the calculated TEFs for each sample was 116 /ig/m^, which is below the primary clearance level of 300 /xg/m\ Based on the pre-cleaning samples, no additional cleaning is required for PAHs. AU of the areas met the primai-y clearance level for PAHs.

Fibrous glass - Sixty-five air samples were collected and analyzed for fibrous glass. All of the samples were below the secondary clearance level of 0.01 fi'cc. In addition, all of the PCM analyses were below the 0.01 fi'cc. PCM analysis results provide another data set that can be used to assess fibrous glass, with the assumption that all detected fibers are fibrous glass, and the PCM data set for 114 Liberty indicates that even if all the fibers fi-om the PCM analysis were fibrous glass, all samples would be below the secondary clearance level of 0.01 f/cc. AU of the areas met the secondary clearance level for fibrous glass.

SiBca - Eleven air samples were collected and analyzed for crystalline silica at a detection limit of 11 gg/m’. Seven samples were below the detection limit and four samples were above the detection limit, with values of 17.2,19.6,22.1, and 22.1 pg/m’. The numeric criterion that USEPA has proposed in the

’ This conclusion does not include the area that contains the pizza shop. As discussed in the letter and the summary of the data, the pizza shop contains asbestos-containing material (ACM) that is in poor condition. The ACM will be addressed through an asbestos abatement project.

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