Analytical results to FEMA, 114 [address], July 2003

NYC 9/11 Public Portal Document

volume) that influence this relationship. EPA’s use of surface wipe and microvacuum sampling at its WTC Residential Confirmation Cleaning Study site (110 Liberty St.) was intended to provide a measure of cleaning effectiveness, and not a risk-based health assessment. EPA’s WTC Residential Confirmation Cleaning Study can be obtained at http://www.epa.gov/wtc/ .

Primarily, risk from asbestos is directly related to its concentration in air. Consequently, post-cleaning aggressive (i.e., use of a leaf blower and fans) air sampling was conducted at 114 Liberty St. by DEP’s contractors to insure that asbestos levels in air met risk-based clearance criteria.

The EMSL analytical report does not provide detailed information on sample collection; however, it appears many samples were collected from inaccessible areas below the hardwood flooring, or from areas of unknown accessibility such as, wall tracking, pipe shafts and I-beams. The scope of work developed for the clean up activities was designed for the removal of debris from the collapse of the World Trade Center and did not include the removal or remediation of pre-existing building materials. As a matter of precaution, any residual dust and, thus, potential reservoirs of asbestos, from accessible areas should be cleaned using the technique of vacuuming and wet-wiping.

Asbestos containing materials (ACMs), such as floor tiles, were observed during DEP’s cleaning of the building. Some of the ACMs may be present under the hardwood flooring, thus samples collected from this location may be more representative of the building materials contained within the building rather than indicating contamination from other sources. Additionally, DEP noted and reported the presence of thermal system insulation and damaged asbestos-containing fireproofing within the building. Building representatives were provided with this information and were informed of the provisions of Title 15, Chapter 1 of the Rules of the City of New York that require the determination of the presence and quantity of ACM prior to alteration, renovation, modification, or demolition activities.

It should also be noted that several errors were detected in the calculation of sample concentrations. Two samples had incorrect concentrations reported, samples 221160-02 and 221160-03 (reported on page 6 of the report) should have reported concentrations of 1,471,401 and 432,765 s/cm , respectively.

Mold and Bacteria Data

Based upon the results that were received, it appears that one sample was collected for mold and bacteria from a kitchen floor and counter on the third floor. The sample was analyzed by P&K Microbiology Services, Inc. with the number and type of fungi and bacteria being counted and identified. Seven fungi species were identified with the highest count for any one species being 900 colony forming units/square inch (CFU/in^ ) and a total sum of 2,200 CFU/in^, while six bacteria species were identified with the highest count for any one species being 500 CFU/in^ and a total sum of 1,600 CFU/in^.

3

NYC-WTC_000160458