Legal hold notice for WTC documents, undated

NYC 9/11 Public Portal Document

Greenwich to Bdway between chambers and Murray Cleanup work continues to be conducted m the area from Greenwidi to Broadway, between Chambers and Murray. Air monitoring was conducted in this area in an effort to move the ate pen’ leter from chambers to murrey. Four air samples were taken in the proposed area each day. These results woe as follows: 9/23/vl Park Place and church .01 fibers/cc Park Place and Greenwich .014 fibers/cc Murray and Church .007 fibers/cc Murray and Greenwich < .01 fibers/cc 9/24/01 Park Place and churdi .007 fibers/cc Park Place and Greenwich .012 fibers/cc Murray and Church .017 fibers/cc Murray and Greenwidi .009 fibers/cc 9/25/01 Results expected at 1600hours 101 Murray St. Indoor air monitoring indicates it is bdow dearance levds. Akhougfa, it remains inside the site perimeter and outside air has not been cleared, onsite emergency personnel should be able to use this frdlity. Other agencies have used TEM Asbestos analysis rather than PCM which is wbat DEP is using. Because oftins they may fed it appropriate to open an area if TEM structures are bdow background. The problem with t^ approach is that fins is a dynamic location effected by many factors. This approach woodwork better indoors in an enclosed static environment. The PCM approach looks at the number of fibers in a spedfic size range rather than asbestos fibers. Therefore this approach errs on the conservative side. Thwefore if we can insure that the fibo* count remains below .01 fibers/cc we can be assured that there are no exposure and cleanup issues. Because this site is dynamic TEM results might give a fidse s«ise of safety since the numbo- of asbestos fibers can change depending which construction vehide!? ♦^“vel through the site. In addition, increased winds whidi move debii fi’om ground zero onto site fiom diffoent locations can change asbestos cmmt. Th^e is also the conaderation of contamination from adjacent areas migrating with nun water. That’s why we bdieve the key is to sustain that the fiber count stay bdow the dearance level rather than worry about spedfic asbestos fiber counts. As

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