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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 19 fixed air 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 18 samples taken in and around ground on October 19. All samples showed results less than 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. This brings the total number of air samples collected and analyzed for lower Manhattan to 1026, with 27 samples above the standard.
Eight air samples taken in New Jersey on October 18 through October 19 showed results less than the school re-entry standard. This brings the total number of samples collected and analyzed in New Jersey to 134, with zero above the standard.
Staten Island Landfill:
Air (Asbestos) - Thirty-eight samples were collected from October 18 through October 19. All samples showed results less than the AHERA standard.
U.S. Government Website