NYC-WTC_000199360

NYC 9/11 Public Portal Document

ewre ASSOCIATES INC. 104 East 25th St., 10th Floor New York, New York 10010 www.atc-en viro. com 212.353.8280 Fax 212.353.8306

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 P. S. 1 (Manhattan) ATC Project No. 15-19125-0340

Dear Mr. Orlan;

ATC Associates Inc. (ATC) is pleased to provide this report of the results of the wipe-samples for polychlorinated dibenzo-p-dioxins (PCDDs)and dibenzofurans (PCDI s) collected on August I 27, 2002, at the referenced location. The New York City Department of l iducation (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. Tie solvent was provided and samples were analyzed by Pace Analytical Services, Inc. (Pace) if Minneapolis, MN, a laboratory experienced in dioxin analysis. The analysis was perforned 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 v ere inherent limitations created by constraints of time, operational and work practice vrriabilily, 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 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; • Hallway by Room 215; • Hallway by Room 403.

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NYC-WTC_000199360