NYC-WTC_000208280

NYC 9/11 Public Portal Document

104 East 25th St., s New York, New York 1 www.atc-eov 'o 212.353,1 Fax 212.353.! ASSOCIATEJ INC.

September 19, 2002

Mr. Bernard P. Ori an 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 Metals Murray Bergtraum High School (M520) ATC Project No. 15-19125-0351

Dear Mr. Ori an;

ATC Associates Inc. (ATC) is pleased to provide this report of air sampling for metals in airborne dust conducted on September 11, 2002, in the referenced school building. The New York City Department of Education (DOE) requested this sampling to verify that acceptable indoor air quality is being maintained.

Scopeof wort

ATC collected three (3) samples for metals at specified locations. Samples were collected for u minimum of eight (8) hours using 37 mm mixed cellulose ester fdters connected to battery-powered sampling pumps at a flow rate of 2 liters per minute. Pumps were calibrated before and after each sampling period. All samples were collected inside the building. Two sample blanks were also submitted. The samples were sent to ESC Analytical Services, Inc., an American Industrial Hygiene Association- accredited laboratory in Reading, PA. Analysis was performed by NIOSH Method 7300M.

Each sample was analyzed for a panel of twelve (12) metals. The metals were; aluminum (Al), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni) and zinc (Zn). A copy of the analytical laboratory report is attached.

Tenzin Namgyal, Industrial Hygienist and Sonny Ramlal, Environmental Technician of ATC’s New York City office, collected the samples consistent with generally accepted industrial hy giene practices. As with all such sampling, there were inherent limitations created by constraints of time, operational and work practice variability, variations in air contaminant concentrations and sampling and analytical accuracy. The results of the sampling represent conditions found on the date the samples were collected.

CITY_21MC100_003021411

NYC-WTC_000208280