NYC-WTC_000188663

NYC 9/11 Public Portal Document

ATC Environmental, Inc. 104 East 25th Street New York, New York 10010

N.Y.C. Board of Education Approved N.Y. State ELAP #10879 28-11 Queens Plaza North ACCREDITED NVLAP Lab Code # 1187 Long Island City, NY 11101 Report Date; 10/18/01

ASBESTOS FIBER ANALYSIS BY TRANSMISSION ELECTRON MICROSCOPY (TEM) With Fiber Identification by Selected-Area Electron Diffraction (SAED) and Energy-Dispersive X-RAY Spectroscopy (EDS) Method: AHERA Final Rule, EPA Federal Register (40 CFR, Part 763)', Vol. 52, No. 210, October 3C, 1987

Sample Identification Analysis Parameters

Project/Site; New Stuwesant H.S., 345 Chambers St., NY, NY TEM Sample No.: 5725 61637 Exterior & Interior of Building & Roof Date Received; 10/18/01 Grid Openings Analysed:__ 4

Project Sample No.: 05 Average Grid Opening -. 106 . QO um

Air Volume Total Area Analyzed: 0,0450 mmG

Filter Type: MCE 25 mtn diam. Pore Size: 0.45 um Analytical Sensitivity:22;2^/mn^ Effective Area; 385 mm2 0.0044 s/cc

FIBROUS PARTICULATES ANALYZED Number Observed CONCENTRATION Total Single Matrix Total. Struct. Filter Air Fibers Bundles Clusters Struct. Struct >=£urn Struct/mm2 Struct/cc ngm/rn3

Chrysotile Asbestos 0 0 0 0 0 0 0.0 0.0000 0

Amphibole Asbestos 0 0 0 0 0 0 0. 0 0.0000 0

Ambiguous 0 0 0 0 0 0 0. 0 0.oooo 0

Total asbestos (includes ambiguous structures) 0 0 0.0 0.0000 0 Non-Asbestos 0 0 0 0 0 0 0.0 0.0000 N/A Nc Identification 0 0 0 0 0 0 0.0 0.0000 N/A

Totals (All Structures) 0 0 0. 0 0.OOOO N/A The estimated uncertainty of this analysis is 1 standard deviation.

Non-asbestos fiber i.d. (EDS/SAED); None detected Amphibole Asbestos Type; None detected

The Analysis was carried out in accordance with the approved TEM method. This laboratory is in compliance with the quality specified for the method.

Analyzed by; Report Reviewed by.

Michael A. Gorycki, Ph.D. Michael A. Gorycki, Ph.D. Director of Electron Microscopy

CITY_21MC100_003082312

NYC-WTC_000188663