NYC-WTC_000231403

NYC 9/11 Public Portal Document ** ■* nr.':

New Vbrt, Nsw vors luy lu

g WWW, ate- envrfO. com 212-353.8380 Fax 212.353.8306 STe s » N c ■

Septeinber 27, 2001

^ironmental ^3 0th street Brk, MY 10001 Mr. . Re; Report of TEM Analysis

3re the results of transmission electron microscopy (tem) of two PCM air samples from our Group No, 5559; ; Mid-Stets HHWb'jecc Mame: 375 Southend Avenue ^^^cation: Apartments 31* and 3H, Building 400 received in TEM Lab; 09/27/01 I^RThese results will confirm and document the data tranemitted. to you ^P^today. The analyses were performed in strict conformance with the methodology of the NIOSH method 7402, Issue 2, August 15, 1994, Forty grid openings from each of the samples were e.xamined at relatively low magnifications (approximately 1,OOOX and io,000X/ ®: for structures greater than Sum in length and widths between o.25um and 3um, and having a iength-to-width ratio graatei- chan 3:1. These structures would be large enough to be observed by PCM analysis. Non-asbestos structures were detected in the samples in the following proportions;

sample gypsum cellulose F/CC as number Asbestos Sv ■

11 0.0% 100.Oi 0.0 12 55.7% 44.3% 0, D

As a consequence, no sample exceeds O.ol F/CC as asbestos. The analyess were supervised by Dr. Michael A. Gorycki, Director of Electron Microscopy. These analyses were performed by ATC d/b/a ATC Associates Inc. This report may be reproduced only in its entirety and not without prior permission of this laboratory.

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CITY_21MC100_008879977

NYC-WTC_000231411