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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.
Air: Fixed Monitors in New York:
Asbestos - EPA analyzed 39 samples taken in and around ground zero on November 14 and 15. 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 lower Manhattan to 2,230, with 28 samples above the standard (27 were collected prior to September 30 and one was collected on October 9).
Staten Island Landfill:
Air (Asbestos) - Fifty-seven samples were collected on November 14 and 15 - all samples analyzed were below the school re-entry standard. One sample was not analyzed due to filter overloading.
Air (Particulates) - EPA used portable monitors to collect samples of particulates from November 15 through18 at the Staten Island Landfill. There were increased readings for particulates on both November 15 and 16, with a significant reduction on November 17. No levels of significance were reported on November 18.
PM 2.5 - Monitoring for fine particulate matter (particles less than 2.5 micrometers in diameter) was conducted from November 14 through November 17 at Pace University, Borough of Manhattan Community College, and the Coast Guard building in Battery Park. All 24-hour averages were below the National Ambient Air Quality Standard (NAAQS) of 65 ug/m3 for all stations. These results were also less than 40 ug/m3, a level on the EPA Air Quality Index indicating that air quality is unhealthy for sensitive populations (e.g., those with respiratory illnesses).
U.S. Government Website