Jump to main content.

Daily Environmental Monitoring Summary

Saturday - Monday, December 29 - 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 5:00 p.m. on 12/31

Air: Fixed Monitors in New York:
Asbestos - EPA analyzed 253 samples taken in and around ground zero from December 19 through December 26. In addition, EPA sampled for asbestos at three lower Manhattan locations from December 18 through 24. All samples showed results less than 70 structures per square millimeter, 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 4,025, with 29 samples above the standard (27 of these were collected prior to September 30, one was collected on October 9 and the other on November 27).

Air: Fixed Monitors outside Lower Manhattan:
Asbestos - Samples were collected from additional asbestos monitors at Public School 154 (33 East 135th St., Bronx), Intermediate School 143 (511 W. 182nd St., Manhattan), P.S. 274 (800 Bushwick Ave, Brooklyn), P.S. 44 (80 Maple Parkway, Staten Island) and P.S. 199 (3290 48th St., Queens) from December 18 through 24. None showed exceedances of the AHERA re-entry standard.

Staten Island Landfill:
Air (Asbestos) - One hundred thirty-seven air samples collected from December 20 through 28 were analyzed for asbestos. All were below the school re-entry standard.

Air (Particulates) - EPA used portable monitors to collect samples of particulates on December 20 and 27-30 at the Staten Island Landfill. An increased reading was noted on Dec. 27 and 30. No other significant readings reported.

Ambient Air Samples:

PM 2.5 - Monitoring for fine particulate matter (particles less than 2.5 micrometers in diameter) was conducted from December 21 through 28 at Pace University, Borough of Manhattan Community College, the Coast Guard building in Battery Park and on Wall Street. All 24-hour averages were below the National Ambient Air Quality Standard (NAAQS) of 65 ug/m3 for all stations. These results were also less than 40 ug/m3, a level on the EPA Air Quality Index indicating that air quality is unhealthy for sensitive populations (e.g., those with respiratory illnesses).

PM10 - Monitoring for particulate matter (particles less than 10 micrometers in diameter) was conducted from December 21 through 28 at a location on Wall Street. All 24-hour average values were below the National Ambient Air Quality Standard of 150 ug/m3.

Particulate Monitoring - EPA used portable monitors to collect samples December 28 through 30 in the following locations: L (north east side of Stuyvesant High School); N (south side of Pier 25); and R (north west side of Stuyvesant High School). All readings were below the OSHA time-weighted permissible exposure limit for particulates.

VOCs - Sampling for volatile organic compounds (VOCs) was conducted on December 25 and December 28 to 30 in the direct area of the debris pile at ground zero. To protect workers at the work site, EPA takes grab samples of VOCs where smoke plumes have been sighted. The results are snapshots of the levels at a moment in time. OSHA's protective standards set a permissible exposure limit (PEL) averaged over an 8-hour day. Benzene exceeded the OSHA standard on December 25 at the North Tower debris pile. There were no exceedances for benzene on the other three days. Eleven of fifteen other samples taken at EPA's Wash Tent (West St. and Murray) and the South Tower debris pile showed no detectable levels of benzene.

Direct Air Readings - EPA did air monitoring in and around ground zero for a number of compounds from December 28 to 30. No significant readings were found.

Latest Available Daily Environmental Monitoring Summary

EPA information about the events of September 11

Jump to main content.