NYC-WTC_000195194

NYC 9/11 Public Portal Document

Asbestos was present in all five wipe samples at lower concentrations than those observed w before cleaning. One of the five samples was identified as being below the detection limit.

Post P‘ Cleaning Samples (Test 4B) - Three air samples and five wipe samples were collected for asbestos. The air samples were analyzed for PCM, TEM AHERA, and PCMe. The PCM results indicate that one sample could not be analyzed due to particulate overloading; two were above the secondary numeric criterion of 0.01 f/cc. The TEM AHERA results indicate that two samples could not be analyzed due to particulate overloading; one sample was above the secondary numeric criterion of 0.022 S/cc. The PCMe results indicate that two of the samples could not be analyzed due to particulate overloading; one was above the primary clearance criterion of 0.0009 S/cc.

The results of the five wipe samples indicate that asbestos was present in all five samples at lower concentrations than those observed before cleaning.

Post P‘ Cleaning Samples (Test 4C) - Five air samples and four micro vacuum samples were collected for asbestos The air samples were analyzed for PCM, TEM AHERA, and PCMe. The PCM analysis could not be conducted due to overloading of the filter with particulate matter. The TEM AHERA results indicate that three of the five samples could not be analyzed due to overloading of the filters with particulate material. The remaining two samples were below the secondary numeric criterion of 0.022 S/cc. The PCMe results indicate that three of the five air samples analyzed could not be analyzed due to overloading of particulate matter. The remaining two PCMe results indicate that one sample was below the primary clearance criterion and one sample exceeded the primary clearance criterion of 0.0009 S/cc at 0.0033 S/cc. <«r The results of the four micro vacuum samples indicate that asbestos was present in all five * samples at lower concentrations than those observed before cleaning, but at similar 9 concentrations to those after Test 4A cleaning.

Post P‘ Cleaning Samples (Test 4D) - Three air samples were collected for asbestos. The samples were analyzed for PCM, TEM AHERA, and PCMe. The PCM results indicate that all three samples were below the secondary numeric criterion of 0.01 Tcc. The TEM AHERA results indicate that all three samples were below the detection limit and below the secondary numeric criterion of 0.022 S/cc. The PCMe results were all below the detection limit and were below the primary clearance criterion of 0.0009 S/cc.

Diojdn Before Cleaning Samples - One air sample and four wipe samples were collected and analyzed for dioxin. The results indicate that there was dioxin present; however, the TEQ w concentration for each sample was below the primary clearance criterion of 4 ng/m^. w w Post P‘ Cleaning Samples (Test 4A) - Four wipe samples were collected and analyzed for dioxin. The TEQ concentration for each sample was below the primary clearance criterion of 4 ng/m^.

Post P‘ Cleaning Samples (Test 4B) - Four wipe samples were collected and analyzed for

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NYC-WTC_000195281