WTC cleanup coordination draft, April 2003

NYC 9/11 Public Portal Document

New York City Department of Environmental Protection Asbestos Control Program

66 John Street, Manhattan 9* and 10* Floors

Commissioner Ward received information from NYCDEP employees concerned about the results of a carpet sample taken from the 10* floor of 66 John Street. The Commissioner contacted the Bureau of Environmental Compliance (BEC) and the Safety Office.

The BEC Asbestos Control Program (ACP) received the result of the carpet sonication sample that indicated a concentration of 393,061 structures/cm^. Carpet sonication is not a New York State Department of Health approved method for the collection and analysis of asbestos-containing or asbestos- contaminated material. Further, this sampling method has not been adopted as a Federal, State or local standard.

A single direct relationship between asbestos-containing dust and potential human exposure has not been established. Although, a direct relationship between dust levels and exposure has been documented for other contaminants, e.g. lead, this relationship has not been documented for asbestos fibers probably due to the unique aerodynamic aspects of asbestos fibers. Asbestos fibers do not pose a health hazard unless the fibers become airborne and are inhaled.

The ACP has responded to calls from concerned building occupants and reviewed air and bulk sample results received from the building owner. The site visits did not disclose the presence of visible debris within the interior of the building. According to the information in the ACP records, 54 air samples were collected within the building on September 14* 15* and 16* 2001. The samples were analyzed by phase contrast microscopy and were each below O.Olf/cc. Ten bulk samples were collected from exterior surfaces during early July 2002. The results indicated the material was not ACM. On November 1, 2002, 9 additional bulk samples were collected from building exterior surfaces. The results indicated the material was not asbestos-containing material. On March 7, 2003, air samples were collected on the 9* 10* and 11* floors. The samples were analyzed by phase contrast microscopy (PCM) and transmission electron microscopy (TEM). The samples were below the clearance levels. Specifically, the clearance level for PCM samples is 0.01 free and for TEM samples is 70 s/mm^.

Although, the results of several previous site visits and the review of submitted results did not indicate a requirement for further action, the Commissioner requested the building owner to re-clean the carpeting. This re-cleaning and subsequent air testing by DEP would provide employees with a sense of reassurance. The building owner agreed to the request and initiated cleaning of the carpet using wet extraction procedures. These procedures are consistent with activities undertaken at other commercial buildings. The cleaning began on April 1, 2003 and is expected to be completed by April 4, 2003. BEC will perform aggressive air sampling on April 4, 2003. During aggressive air sampling, the air is circulated to simulate activity in the area. The aggressive sampling is the most effective, approved, and accepted method to evaluate potential risk to building occupants. The results will be evaluated using the clearance criteria indicated above.

NYC-WTC_000160134