NYC-WTC_000196746

NYC 9/11 Public Portal Document

CFATC 104 East 25th St, 10th Fl New York, New York 10010 www.atc-enviro com 212 353 8280 Fax 212.353 8306 ASSOCIATES INC.

September 13, 2002

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

Re: Air Sampling for Hydrocarbons P. S. 42M ATC Project No. 15-19125-0342

Dear Mr. Orlan:

ATC Associates, Inc. (ATC) is pleased to provide this report of the results of air sampling for volatile hydrocarbon compounds conducted on September 4, 2002, at the referenced school. The New York City Department of Education (DOE) requested this sampling prior to the resumption of classes to verify that acceptable indoor air quality is being maintained.

Scope of Work

ATC collected three (3) samples for hydrocarbon compounds (HC) at specified locations. Samples were collected for 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. 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).

Wagdi Abdelshahid, Industrial Hygienist and Yannis Efstathiou, Project Manager 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 A- hydrocarbons are those, such as gasoline or light alcohols, with boiling points less than that of benzene (ITb^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 laboratory report is attached.

CITY_21MC100_003042743

NYC-WTC_000196746