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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 99 samples taken in and around ground zero from October 12 through October 15. 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 876, with 27 samples above the standard.
Twelve air samples taken in New Jersey from October 12 through October 14 showed results less than the school re-entry standard. This brings the total number of samples collected and analyzed in New Jersey to 114, with zero above the standard.
Staten Island Landfill:
Air (Asbestos) - 17 samples that were collected on October 9, which have not been previously reported, showed results below the AHERA standard used for allowing re-entry into schools. An additional 50 samples were collected from 6:00 a.m. on October 13 through 8:00 p.m on October 14; all of these results were also below the AHERA standard.
Particulate Monitoring - Samples collected on October 14 and 15 using portable monitors showed no significant readings.
PBCs - The PCB results of one bulk sample collected from the lobby of 110 Greenwich on September 26 showed no detectable levels of PCBs.
Dioxin - One bulk sample collected from the lobby of 110 Greenwich showed levels of dioxin below the residential cleanup goal of 1 part per billion.
Ambient Air Sampling:
VOCs - Sampling for volatile organic compounds (VOCs) was conducted on October 15 in the smoke plume within the debris pile at ground zero. Benzene exceeded the OSHA time-weighted average permissible level at two locations. Significant reductions of overall VOC concentrations, including benzene, were observed around the South Tower (the debris pile) in comparison to previous data.
PCBs - (CORRECTION to 10/14 DAILY SUMMARY) - Trace amounts of PCBs were detected in three of the ten samples collected on October 4; however, these values are all below levels of concern. Seven samples did not detect any PCBs. All samples results were below the level at which EPA would take an action to reduce exposures.
U.S. Government Website