NYC-WTC_000182534

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: 10/06/01

ASBESTOS FIBER TiNTVLYSIS 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 7G3) , Vol. 52, No. 210, October 30, 1987

Samole Identification Analysis Parameters

Project/Site: New Stuwesant H.S., 345 Chambers St., NY, NY TEM Sample No.: S623 - 6034S Exterior of Building a Roof Date Received; 10/06/01 Grid Openings Analyzed:__ 4

Project Sample No.: NSHS-EBR-10/6-01 Average Grid Opening; 106.00 urn

Air -Volume; 1890 liters Total Area Analyzed: 0.0450 mmS

Filter Type: MCE 25 mm diam. PoreSizej 0,45uin Analytical Sensitivity: 22.2 s/nim2 Effective Area: 385 nirn2 0.0045 s/cc

FIBROUS PARTICULATES ANALYZED Number Observed CONCENTRATION Total single Matrix Total, struct. Filter Air Fibers Bundles Clusters Struct, Struct >=5um Struct/mra2 Struct/cc ncpn/mS

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 0.0000 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 No Identification 0 0 0 0 0 0 0.0 0.0000 N/A

Totals (All Structures) 0 0 0.0 0.0000 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:

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

CITY_21MC100_003099229

NYC-WTC_000182534