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Daily Environmental Monitoring Summary

Tuesday and Wednesday, October 30 & 31, 2001

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.

Results as of 7:00 p.m. on 10/31

Air: Fixed Monitors in New York and New Jersey:
Asbestos - EPA analyzed 102 samples taken in and around ground zero from October 26 through October 29. 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 1485, with 28 samples (27 of these were collected prior to September 30 and one on October 9) above the standard.

Four air samples taken in New Jersey on October 27 and an additional four air samples collected on October 29 showed results less than the school re-entry standard. This brings the total number of samples collected and analyzed in New Jersey to 161, with zero above the standard.

Staten Island Landfill:
Air (Asbestos) - Seventeen samples were collected on October 25 . Three samples, one at Location 13 (barge station), one at Location 9A (sift area) and one at Location 12B (wash area) exceeded the school re-entry standard. These incidents are being investigated further. All of the remaining samples showed results less than the school re-entry standard.

An additional 102 samples were collected from October 26 through October 29, all of these samples showed results less than the school re-entry standard.

Particulate Monitoring - Samples collected on October 29 using portable monitors showed an increase in concentrations from the previous day's readings.

Ambient Air Sampling:
Dioxin - Ten samples were collected on October 15 and analyzed for dioxin/furans. Two of the samples (Location 3 - SW of WTC Building #5 and Location B - Church and Dey St.) showed results above the level at which EPA would take some type of action to reduce people's exposure. This action guideline is based on a 30-year exposure. However, none of the samples were above the EPA action guideline adjusted to a one-year exposure. These levels do not pose a short-term health affect but should be monitored if they persist for a longer period of time.

PCBs - Sampling for polychlorinated biphenyls (PCBs) was conducted on October 15. PCBs were not detected in nine of the samples. One sample showed trace amounts, below levels of concern.

Silicates - Ten samples were collected on October 15 and analyzed for silicates, silicates were either not detected or were detected at levels below the NIOSH Recommended Exposure Limit (REL) time-weighted average of 0.05 mg/m3.

VOCs - Sampling for volatile organic compounds (VOCs) was conducted on October 29 in the direct area of the debris pile at ground zero. Benzene exceeded the OSHA time-weighted average permissible level at one location (North Tower) at ground level. Benzene levels on the debris pile are significantly reduced from those noted over the past week. Freon-22 (chlorodiflouromethane) was detected and confirmed in samples collected from within the debris pile of the North Tower at ground level. Levels detected were well below the NIOSH recommended exposure limit of 1,000 ppm. EPA is working with the local agencies and health and safety officers working at ground zero to closely monitor this situation so that workers can take appropriate precautions.

PM 2.5 - Monitoring for fine particulate matter (particles less than 2.5 micrometers in diameter) was conducted October 28 through October 29 at Pace University, the Borough of Manhattan Community College, and the U.S. Coast Guard building located in Battery Park. All 24-hour average values were below the National Ambient Air Quality Standards (65 ug/m3) for all stations. These results were also less than 40 ug/m3, an EPA air quality index which would indicate the air quality is unhealthy for sensitive populations (e.g., those with respiratory illnesses).

Direct Air Readings - Using portable monitors, direct air readings were taken in and around ground zero on October 29, nothing of significance was reported.

Other Air Samples - Ten indoor air samples were collected on October 23 and analyzed for asbestos from 100 Church Street, all samples showed results less than the school re-entry standard.

Bulk/Dust:
Asbestos - Nine samples were collected on October 26 from various steel piles at or near ground zero, 1 sample, collected from a steel pile located on West Street contained chrysotile at greater than 1%.

Staten Island Landfill - Eight samples were collected on October 24 from destroyed vehicles sent to the landfill, 2 samples contained chrysotile at greater than 1%. Six samples were collected from various bulk steel piles. Two samples contained chrysotile at greater than 1%.

Latest Available Daily Environmental Monitoring Summary

Resources on the World Wide Web:

EPA information about the events of September 11

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