NYC-WTC_000228707

NYC 9/11 Public Portal Document

104 East 25th St. 10th Floor New York. New York 10010 tAAvwaic-enviro.com 212,353.8280 Fax 212 353 8306 ASSOCIATES INC.

June 6, 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 of Economics and Finance ATC Project No. 15-19125-0279

Dear Mr. Orlan:

ATC Associates, Inc. (ATC) is pleased to provide this letter report of air sampling for hydrocarbon compounds conducted on May 4 and 11, 2002, at the referenced school. The New York City Board of Education (BOE) requested this sampling to evaluate air quality in the school building prior to re-occupancy.

Scope of Work

On each day, ATC collected four (4) samples for hydrocarbon compounds (HC) at locations throughout the building. 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. Seven (7) samples were collected inside the building and two (2) were 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 (NIOSH Methods 1003, 1005, 1022, 1300, 1500, 1501).

Wagdi Abdelshahid and Tenzin Namgyal, Industrial Hygienists from ATC’s New York City office, conducted the sampling consistent with accepted industrial hygiene practices. The results represent conditions on the day the samples were collected.

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 total other A-hydrocarbons (TOAHC) are those, such as gasoline or light alcohols, with boiling points less than that of benzene (176“F). The total other B-hydrocarbons (TOBHC) 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.

The sampling locations were: floor Mam Lobby, 5“* floor by Stair B, IO* floor by Stair B, and the Roof.

CITY_21MC100_002901390

NYC-WTC_000228707