NYC-WTC_000223537

NYC 9/11 Public Portal Document

104 East 25th Street 10th Floor New York, New York 10010-2917 212.353.8280 Fax 212.353.8306 INC.

January 7, 2002

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

Re: Air Sampling for Dioxins P.S. 234M ATC Project No. 15-19125-0279

Dear Mr. Orlan:

ATC Associates, Inc. (ATC^hs pleased to provide this letter report of the results of air sampling for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) conducted on December 12, 2001, at the referenced school. The New York City Board of Education (BOE) requested this sampling at the recommendation of Environ Corp., a consultant retained by the parents association.

SCOPE OF WORK

ATC collected eight (8) samples for dioxins at specified locations. Samples were collected for twenty-four (24) hours using polyurethane foam (PUF) cartridges and General Metal Works samplers. Total sample volumes were 430 to 617 cubic meters of air (m^). Pumps were calibrated using vendor-provided software and a laptop computer. Four (4) samples were collected inside the building and four (4) were collected outdoors. The PUFs were provided and analyzed by Pace Analytical Services, Inc., (Pace) of Minneapolis, MN, a laboratory experienced in dioxin analysis. The analysis was performed by Method TO-9 with modifications from EPA Method 23 using combined capillary column gas chromatography/high resolution mass spectrometry A copy of the complete laboratory report is attached..

The sampling locations were specified by the parents association consultant. They were as follows: Cafeteria, Room 118, 2"‘‘ floor hallway, Room 315, Outdoors by main entrance. Outdoors in front courtyard. Outdoors in back playground. Roof by the air intake.

SUBSTANCE DESCRIPTION

“Dioxins” or “dioxin” is a name used for a group of chlorinated multi-ringed organic compounds that includes polychlorinated dibenzo dioxins (PCDDs) and polychlorinated dibenzo furans (PCDFs). They are related to polychlorinated biphenyls (PCBs). PCDDs and PCDFs are hot . produced commercially except for research purposes. They occur as trace level by-products of combustion and industrial chemical processes.

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NYC-WTC_000223537