NYC-WTC_000197436

NYC 9/11 Public Portal Document

Oatc 104 East 25th St.. 10th Floor New York, New York 10010 www.atc-enviro.com 212.353.8280 Fax 212.353,8306 ASSOCIATES INC.

May 24, 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. Ori an:

ATC Associate's, Inc. (ATC) is pleased to provide this report of air sampling for hydrocarbon compounds conducted on April 12, 19 and 26, 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

On all dates, 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 per day. 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/Hame ionization detection (OSHA Method 7).

Tenzin Namgyal and Wagdi Abdelshahid, Industrial Hygienists from ATC’s New York City office, collected the samples. The sampling was conducted in accordance with accepted industrial hygiene practices. The results represent conditions on the days 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 A- hydrocarbons Eire those, such as gasoline or light alcohols, with boiling points less than that of benzene (176°!'). The B-hydrocarbons are those, such as mineral spirits or petroleum naphtha, with boiling points greater than that of benzene. Copies of the analytical laboratory reports are attached.

CITY_21MC100_003029376

NYC-WTC_000197436