NYC-WTC_000197432

NYC 9/11 Public Portal Document

104 East 25th St New York. New York 10010 www.atc-enviro.com 212.353.8280 Fax 212.353.8306 ASSOCIATES INC.

February 28, 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 Hydrocarbons High School for Leadership & Public Service (894M) ATC Project No. 15-19125-0290

Dear Mr. Orlan:

ATC Associates, Inc. (ATC) is pleased to provide this letter report of air sampling for hydrocarbon compounds conducted on February 15, 2002, at the referenced school. The New York City Board of Education (BOE) requested these samples to determine if acceptable indoor air quality is being maintained.

Scope of Work

ATC collected four (4) samples for hydrocarbon compounds (HC) at various locations. Samples were collected for a minimum of ten (10) hours using activated coconut shell charcoal tubes connected to battery-powered sampling pumps at a flow rate of 0.2 liters per minute. Pumps were calibrated before and after each sampling period. Three (3) samples were collected inside the building and one (1) was collected outside. One blank tube was also submitted. The samples were sent to PSC Analytical Services, Inc., an American Industrial Hygiene Association- accredited laboratory in Reading, PA. Analysis was performed by capillary gas chromatography''flame ionization detection (OSHA Method 7).

Each sample was analyzed for a panel of sixteen (16) specific HC compounds. These compounds were: pentane, acetone, methylene chloride, hexane, chloroform, methyl chloroform, benzene, 1,2-dichloroethane, trichloroethylene, toluene, perchloroetyhylene (tetrachloroethylene), chlorobenzene, ethylbenzene, styrene, cumene and xylenes. In addition, two non-identified peaks, total other A hydrocarbons and total other B hydrocarbons, were reported. The A- hydrocarbons an; those, such as gasoline or light alcohols, with boiling points less than that of benzene (176“F), The B-hydrocarbons are those, such as mineral spirits or petroleum naphtha, with boiling points greater than that of benzene. A copy of the analytical report is attached.

Results

None of the HCs in the panel were found at levels above the limits of detection for the analyses in any of the samples.

CITY_21MC1OO_OO3O29357

NYC-WTC_000197432