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Daily Environmental Monitoring Summary

Thursday, March 21, 2002

The U.S. Environmental Protection Agency (EPA) and other federal, state and local agencies have collected extensive environmental monitoring data from the World Trade Center site and nearby areas in Manhattan, Brooklyn and New Jersey. Since September 11, EPA has taken samples of the air, dust, water, river sediments and drinking water and analyzed them for the presence of pollutants that might pose a health risk to response workers at the World Trade Center site and the public. The samples are evaluated against a variety of benchmarks, standards and guidelines established to protect public health under various conditions. EPA is collecting data from more than 20 fixed air monitors in and around ground zero and additional monitors in the Bronx, Brooklyn, Queens and Staten Island. The Agency is also using portable sampling equipment to collect data from a range of locations.

Results as of 4:00 p.m. on 3/21

Lower Manhattan:

Air Sampling for Asbestos - EPA analyzed 68 samples taken in and around ground zero from March 14 through March 16. All samples showed results less than 70 structures per square millimeter, which is the Asbestos Hazard Emergency Response Act (AHERA) standard for allowing children to re-enter school buildings after asbestos removal activities.

This brings the total number of air samples collected and analyzed for asbestos in lower Manhattan to 7,065, with 18 samples above the standard (11 of these were collected prior to September 30; the other seven were collected on October 9, November 27, December 27, January 14, February 5, February 11 and March 9).

Air Sampling for VOCs - Sampling for volatile organic compounds (VOCs) was conducted on March 19 and March 20 in the direct area of the excavation at ground zero. To protect workers at the work site, EPA takes grab samples of VOCs where smoke plumes have been sighted. The results are snapshots of the levels at a moment in time. OSHA's protective standards set a permissible exposure limit (PEL) averaged over an 8-hour day.

All samples taken on March 19 and March 20 at EPA's Wash Tent (West & Murray Streets), Austin Tobin Plaza, and the North Tower and South Tower excavation areas showed no detectable levels of VOCs.

Staten Island Landfill:

Air Sampling for Asbestos - A total of 75 samples were collected on March 7, 12, 13 and 14. A sample collected on March 14 at the northern perimeter of the landfill, (Location "P-5"), showed 78.74 structures per square millimeter, which exceeds the AHERA school re-entry standard. All other samples were below the school re-entry standard.

Latest Available Daily Environmental Monitoring Summary

EPA information about the events of September 11

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