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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 34 samples taken in and around ground zero from October 1 to October 2. 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 schools after asbestos removal activities (Link to map). This brings the total number of air samples collected and analyzed for lower Manhattan to 476, with 27 samples above the standard.
Four air samples taken in New Jersey on September 30 were all below the school re-entry standard. This brings the New Jersey total to 58 samples, with no readings above the standard.
Staten Island Landfill
Asbestos - Twenty-two air samples were taken from Oct. 1 to Oct. 2. All test results were below the AHERA standard used for allowing re-entry into schools.
Particulate Monitoring - Samples taken on October 2, showed no significant results based on average daily concentrations.
Ambient Air Sampling:
PCBs - Ten samples were taken on September 23 in the area of the emergency response operations. Of these, eight results did not detect polychlorinated biphenyls (PCBs); the two that had a measurable result were below levels of concern.
Dioxin - Ten dioxin samples were taken on September 23 in and around ground zero. All samples were at or above EPA's removal action guideline based on continuous long-term exposure over 30 years. These levels are expected to decrease significantly once the fires under the World Trade Center debris pile are extinguished.
VOCs - Sampling for volatile organic compounds (VOCs) was conducted on Oct. 2 at the World Trade Center site. Benzene was detected at an increased concentration from previous samples taken in the smoke plume on the debris pile. These measurements assist response workers in determining the appropriate level of respiratory protection.
Metals - On September 28, at the request of the Ground Zero Elected Officials Task Force, EPA took wipe samples inside two lower Manhattan schools. Eight samples were collected at the Borough of Manhattan Community College. One exceeded the federal Department of Housing and Urban Development (HUD) criteria for lead (50 micrograms per square foot). Other metals were detected at low concentrations. Also on September 28, seven samples were collected indoors at Stuyvesant High School; lead results were below the HUD criteria and other metals were detected at low concentrations.
Both schools have been cleaned by independent contractors. The New York City Board of Education will resample the indoor air at Stuyvesant for asbestos. EPA has indicated its availability to provide technical assistance to the Board of Education.
U.S. Government Website