NYC-WTC_000197651

NYC 9/11 Public Portal Document

104 East 25th Street New York, New York 10010 www.atc-enviro.com 212.353.8280/’: Fax 212.353.8306 ASSOCIATES INC.

January 15, 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 Metals Stuyvesant High School ATC Project No. 15-19125-0246

Dear Mr. Orlan:

ATC Associates, Inc. (ATC) is pleased to provide this letter report of air sampling for metals in airborne dust on January 3, 2002, at the referenced school. The New York City Board of Education (BOE) requested this sampling at the recommendation of H. A. Bader, a consultant retained by the parents association.

Scope of Work

ATC collected three (3) samples for metals at specified locations. Samples were collected for eight (8) hours using 37 mm mixed cellulose ester filter connected to battery-powered sampling pumps at a flow rate of 2 liters per minute. Pumps were calibrated before and after each sampling period. Two (2) samples were collected inside the building and one (1) was collected on the roof. One blank sample was also submitted on each day. The samples were sent to PSC Analytical Services, Inc., an American Industrial Hygiene Association-accredited laboratory in Reading, PA. Analysis was performed by NIOSH Methods 7300M. Each sample was analyzed for a panel of eleven (11) metals. The metals were aluminum (Al), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni) and zinc (Zn) A copy of the analytical report is attached.

The sampling locations, specified by the parents association consultant, were as follows: • 1“ floor lobby; • 2'“’ floor bridge entrance hallway; • Roof by the air intake.

The established regulatory values for metals are intended for industrial workplace exposures and are not generally applicable to office/school settings. There are no standards for these metals in indoor air in non-industrial situations. The Environmental Protection Agency has set a screening level for hexavalent Cr (the more toxic form) of 0.6 micrograms per cubic meter of air (0.6 ug/m’). These samples were analyzed for both hexavalent and trivalent Cr. The EPA level is based on continuous exposure for one year.

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NYC-WTC_000197651