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Daily Environmental Monitoring Summary

Thursday, April 11, 2002

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 11:00 a.m. on 4/12

Lower Manhattan:

Air Sampling for Asbestos - EPA analyzed 123 samples taken in and around ground zero on March 9, and from April 3 through April 6. EPA also sampled for asbestos at two additional lower Manhattan locations from March 29 through April 2. 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 asbestos in lower Manhattan to 7,939, with 21 samples above the standard (11 of these were collected prior to September 30; the other 10 were collected on October 9, November 27, December 27, January 14, February 5, February 11, March 9, March 29, March 30 and April 2).

Air Sampling for Particulates - EPA collected samples on April 10 at Location "L" (northeast side of Stuyvesant High School), Location "N" (south side of Pier 25), and Location "R" (northwest side of Stuyvesant High School). All readings were below the OSHA time-weighted permissible exposure limit for particulates.

Air Sampling for Dioxin - A total of 20 samples were collected on March 19 and March 21 from several locations in lower Manhattan. All samples collected were below the EPA Removal Action guidelines (based on a 30-year exposure).

Air Sampling for Silicates - A total of 30 samples were collected on March 21, March 26, and March 28 at several locations in lower Manhattan. Silicates were either not detected, or were below the NIOSH Recommended Exposure Limit (REL) time-weighted average of 0.05 mg/m3.

Air Sampling for VOC's - Sampling for volatile organic compounds (VOC's) was conducted on April 10 in the direct area of the excavation at ground zero. To protect workers at the work site, EPA takes grab samples of VOC's 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.

All samples taken on April 10 at EPA's Wash Tent (West & Murray Streets), Austin Tobin Plaza, and the North Tower and South Tower excavation areas showed no detectable levels of VOC's.

Staten Island Landfill:

Air Sampling for Asbestos - A total of 113 samples were collected on March 24, and from April1 through April 5. A sample taken on April 3 at a barge loading area (Location "B-14") showed 91.86 structures per square millimeter, which exceeds the AHERA school re-entry standard. All other samples were below the school re-entry standard.

Air Monitoring for Particulates - There were no significant readings from samples collected on April 10.

Air Sampling for Metals - A total of 10 samples were collected on March 15 and March 21. Metals in all samples were either not detected or were below applicable EPA Removal Action level guidelines, OSHA PELs, and the NAAQS for lead.

Elsewhere in New York City:

Air Sampling for Asbestos - Samples were collected on March 26, and from March 29 through April 2 at Intermediate School 143 (511 W. 182nd St., Manhattan) and Public School 199 (3290 48th St., Queens). Samples were also collected on March 26, March 29, April 1, and April 2 at P.S. 154 (333 East 135th St., Bronx). Samples were also collected from March 29 through April 2 at P.S. 274 (800 Bushwick Ave, Brooklyn) and P.S. 44 (80 Maple Parkway, Staten Island). None showed exceedances of the AHERA re-entry standard.

Latest Available Daily Environmental Monitoring Summary

EPA information about the events of September 11

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