NYC-WTC_000202245

NYC 9/11 Public Portal Document

(Swre ASSOCIATES INC. 104 East 25th St. 10th Floor New York, New York 10010 www.atc-enviro.com 212.353.8280 Fax 212.353.8306

April 26, 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 Silica P.S. 89M ATC Project No. 15-19125-0297

Dear Mr. Orlan:

ATC Associates, Inc. (ATC) is pleased to provide this letter report of air sampling for silica- containing dust conducted on April 4, 2002 at the referenced school. The New York City Board of Education (BOE) requested this sampling at the recommendation of Environ Corp., the consultant to the parents association.

Scope of Work

ATC collected ten (10) samples respirable dust using pre-weighed 37mm PVC filters connected to size-selective cyclones to remove the larger (non-respirable) particles prior to deposition on the filters. All samples were collected indoors. The samples were sent to PSC Analytical Services, Inc., an American Industrial Hygiene Association accredited laboratory in Reading, PA. One blank filter was also submitted. Silica analysis was performed by x-ray diffraction according to OSHA Method 142. A copy of the analytical report is attached.

Tenzin Namgyal and Wag,di Abdelshahid, Industrial Hygienists of ATC’s New York City office, collected the samples consistent with generally accepted industrial hygiene practices. The results of the sampling represent conditions found on the dates of the survey and may not represent . conditions found at other times.

The sampling locations were: the D' floor hallway by cafeteria (North), floor hallway by Cafeteria (South), Cafeteria, Gymnasium, Auditorium, Room 328 (north). Room 310 (east), Room 302 (south), 2”'^ floor hallway (South), and 4“^ floor hallway (South).

Results

Silica was not present above the limit of detection (<10 micrograms per sample) in any of the ten samples.

CITY_21MC100_003271172

NYC-WTC_000202245