Air monitoring report for ambient asbestos in Lower Manhattan

NYC 9/11 Public Portal Document

Air Monitoring in Lower Manhattan Page 1 of3

k The City OF New York i Department of Environmental Protection

Air, Noise and Hazardous Materials

itteeb: Air Monitoring in Lower Manhattan TreatmctTt DEP is monitoring the ambient outdoor air for asbestos. This effort is augmenting ambient air asbestos sampling being done by the EPA and other state and city agencies. There is currently no outdoor ambient standard for asbestos. The US and NYC standard for asbestos in community and residential buildings is 0.01 fibers/cubic centimeter (f/cc) in indoor air. An indoor area which has had asbestos detected and then removed must show that air samples are at or below the 0.01 f/cc standard before the indoor area can be re-occupied. Although the ambient QASbfeStOi outdoor air is being monitored, DEP is using this value as a way to characterize the levels of asbestos in the air.

Since the measurement protocol used, phase contrast microscopy (PCM), counts fibers, DEP is also conducting an Rotes additional analysis for all samples that are above 0.01 ficc. This measurement protocol is called transmission y^Asbestos electron microscopy (TEM) and counts the number of asbestos fibers in the sample. EPA is reporting their data in TEMs, and provides a good explanation of the interpretation of the standard that uses this methodology on their website. Acoountiibiia', Results indicate that, as expected, asbestos is present in some of the debris at the site and in areas very close to the <^Burc3<js site. Between September 28, 2001 and the present, the vast majority of air sampling results outside the security aw . zone have been below the standards for asbestos in indoor air.

asssgspi, As testing continues, there may be the possibility of occasional short-term increases in levels of asbestos in the air above the residential standard of 0.01 fi'cc of air. When the measured level for the outdoor ambient air is above 0.01 f/cc, the samples will be analyzed to determine how many of the fibers are actually asbestos fibers. OHs!a.C§na£ To view recent air monitoring results, click on a sampling location below or on the map (Link, win open in, new browser window); ■llufonnaaor-

Sampling Site Location O PEP News 1 West.Broadway and Worth 19 Vesey and West Street Sheet 2 Broadway and Worth Street 20 Vesey between Church and tm Greenwich Street 3 Duane Street and Trimble 20A Vesey and West riace Broadway 4 River Terrace and Chambers Street 21 Fulton and Church Street 3 5 Chamhers^and North End 22 Fulton between Avenue Churchand Broadway 6 Greenwich and Chambers 23 Church and Dev Street 6A y/est end of Warren Strect 24 Liberty_Sttvet and

a South End Avenue 7 Warren Street and North 25 Liberty and Church End Avenue Stre^ 8 West Street and Warren 26 Liberty and Street Broadway 8A RiverTerraceJ’ark area 27 Gateway Plaza Park __ between Park Placc and Area SST*/? / Warren Street 9 River Terrace and Park 28 Washington and PlaceWest Cedar Street

http;//www.nyc.gov/html/dep/html/airmonit.html 9/24/02

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