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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 17 fixed monitors in and around ground zero and is using portable sampling equipment to collect data from a range of locations.
Air: Fixed Monitors in New York and New Jersey:
Asbestos - EPA analyzed 16 samples taken in and around ground zero area on October 3. All samples showed results less than the 70 structures per millimeter squared, which is the Asbestos Hazard Emergency Response Act (AHERA) standard for allowing children to re-enter school buildings after asbestos removal activities (Link to map). One sample was not analyzed due to overloading of particulates. This brings the total number of air samples collected and analyzed for lower Manhattan to 526, with 27 samples above the standard.
Eight air samples taken in New Jersey from October 2 and 3 were all less than the school re-entry standard. The total samples taken for New Jersey is 70, with zero above the standard.
Dust - Two samples were taken on October 4 at 140 West Street in lower Manhattan; results showed no detection of asbestos. The total number of dust samples taken for lower Manhattan is 138, with 34 over 1%.
Staten Island Landfill
Air (Asbestos) - Ten air samples were taken on October 3. All test results were below the AHERA standard used for allowing re-entry into schools.
Particulates - EPA detected a rise in the average concentration of particulates at several locations on October 4. Changes in average levels are monitored to determine if dust suppression is necessary.
U.S. Government Website