NYC-WTC_000199458

NYC 9/11 Public Portal Document

(SftTC 104 East 25th St., 10th Floor New York, New York 10010 www.atc-en vi ro. com 212.353.8280 Fax 212.353.8306 ASSOCIATES INC.

November 25, 2002

Mr. Bernard P. Orlan Director, Environmental Health & Safety New York City Department of Education 28-11 Queens Plaza North Long Island City, NY 11101-4008

Re: Wipe Samples for Dioxins DeSoto School (P. S. 130 Manhattan) ATC Project No. 15-19125-0345

Dear Mr. Orlan:

ATC Associates Inc. (ATC) is pleased to provide this report of the results of the wipe-samples for polychlorinated dibenzo-p-dioxms (PCDDs)and dibenzofurans (PCDFs) collected on August 26, 2002, at the referenced location. The New York City Department of Education (DOE) requested these samples to evaluate possible contamination in the school building.

Scope of Work

The samples were collected using gauze pads and hexane as a solvent. The solvent was provided and samples were analyzed by Pace Analytical Services, Inc. (Pace) of Minneapolis, MN, a laboratory experienced in dioxin analysis. The analysis was performed by modified EPA Method 8290 using combined capillary column gas chromatography/high resolution mass spectrometry.

Wagdi Abdelshahid, Industrial Hygienist of ATC’s New York City office, collected the samples consistent with generally accepted industrial hygiene practices. There were inherent limitations created by constraints of time, operational and work practice variability, variations in contaminant concentrations, and sampling and analytical accuracy. The results of the sampling represent conditions found on the date the samples were collected.

Results

ATC submitted three wipe samples for PCDDs/PCDFs (plus one blank) to Pace for analysis. Samples were taken from representative floor areas throughout the building. The sample area for each sample was one square meter (1 m2). The areas sampled were:

• Main Lobby; • 4th Floor Hall by Stair C; • 5th Floor Hall by Stair B.

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NYC-WTC_000199458