Asbestos sampling summary, 66 and 90 Chambers Street, November 2001

NYC 9/11 Public Portal Document

Summary of Asbestos Sampling Results Page 2 of 3 Address: 66 Franlfort St and 90 Gold St Date sampled: November 20, 2001

and the total fiber count is then compared to the asbestos standard. If the results were above 0.003 f/cc using the PCM methodology, additional analysis was performed to determine whether any of the fibers were asbestos. In this building, additional analysis was not warranted since the air sampling results in your building were not greater than 0.003 f'cc

Results of Phase Contrast Microscopy (PCM) testing of air at 66 Frankfort St and 90 Gold St ., November 20, 2001_______________________________________________________________ Area Sampled Outside Common Residence 1 Residence 2 Sample Numbers A-0-11 A-C-11 A-Rl-11 A-R2-11 A-C-X-11 * Concentration of Fibers in Air <0.001 <0.001 <0.001 <0.001 At this location (f/cc)** <0.001 * Concentration of Fibers in Air <0.001 to 0.001 <0.001 to 0.002 <0.001 to 0.002 <0.001 to 0.003 at comparison locations (f/cc)

NYC Re-occupancy Standard 0.01 0.01 0.01 0.01 (f/cc)*** I '.-..I. ____ __ - ------------- —

* Denotes a second air sample was taken at the same location for quality control purpose. ** f/cc is fibers in each cubic centimeter (cc) of air. This is calculated from the number of fibers seen on the air filter and the volume of air pulled through the filter measured in cubic centimeters. *** New York City Department of Environmental Protection asbestos clearance criteria for post-abatement work (Rules of the City of New York. Title 15, Chapter 1)

ASBESTOS DUST TEST RESULTS

The dust and debris samples were examined by two different laboratory methods for asbestos fibers. Polarized Light Microscopy (PLM) and Transmission Electron Microscopy (TEM). PLM is used to define asbestos containing material in dust and debris. A material is considered to be asbestos containing material if it contains more than 1% asbestos using the PLM method. The PLM method only counts the larger asbestos fibers. TEM analysis can detect smaller fibers, but is not used for regulatory purposes on dust samples.

Asbestos was not detected in the indoor dust samples using the PLM method. Further analysis of the indoor dust by the more specific TEM method detected some asbestos in the unoccupied residences. Therefore the matter was referred to the New York City Department of Environmental Protection for follow-up inspection. One of the residences had not been cleaned since the collapse of the World Trade Center and it was unclear whether the other residence had been cleaned recently or not.

No asbestos was detected in the settled dust from the lobby by either method. Not enough dust was available for sampling in the outdoor area.

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