NYC-WTC_000229567

NYC 9/11 Public Portal Document

a 104 East 25th St.. 10th Floor New York, New York 10010

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June?, 2002

Mr. Bernard P. Orlan Director, Environmental Health & Safely New York City Board of Education 28-Il Queens Plaza Norte Long Island City, NY 11101-4008

Re: Wipe Samples for Dioxins High School for Leadership and Public Service (M894) ATC Project No. 15-19125-0290

Dear Mr. Orlan:

ATC Associates tec. (ATC) is pleased to provide this report of the results of the wipe samples for polychlorinated dibenzo-p-dioxins (PCDDs)and dibenzofiirans (PCDFs) collected on May 3, 2002-at tee referenced location. The New York City Board of Education (BOE) requested these samples to evaluate possible contamination in the school building.

SCOPE OF WORK

The samples wcrc collected using gauze pads and hexane as a solvent. The pads and solvent were provided and samples were analyzed by Pace Analytical Services, Inc. (Pace) of Minneapolis, MN, a laboratory experience 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 saniples 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 dates the samples were collected.

SA1Ma>lJNG RESULTS

On^h teiy, ATC submitted three (3) wipe samples for PCDDs/PCDFs to Pace for analysis. A copy of tee laboratory analysis report is provided in the Attachment. Samples were taken from «eas in various parts of the building. The sample area was one square meter (1 m2).

Each sample was «islyzed for sixteen (16) PCDD^QDF isomers. The results for each isomer were then converted to 2, 3, 7, 8 -tetrachloro-dibenzo-p-dioxin (2, 3, 7, 8-TCDD) equivalents by multiplying by an established equivalency factor.

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