Environmental assessment report, 100 Church Street, April 2002

NYC 9/11 Public Portal Document

protocol prior to placement on newly installed carpeting, and a second time as part of the capital cleaning program, which also followed a specific wet-wipe protocol.

TRC also sampled soft goods, such as cloth chairs, couches, fabric wall partitions. None of the thirty-one (31) samples exceeded the individual sample post-cleaning target and the geometric mean was less than 1,000 slr/cm ’. Twenty-two (22) samples were found to be below the analytical detection limit. Although results indicated that no action was required, all fabric based chairs, couches and fabric partitions were steam cleaned.

TRC sampled internal components of computers and copiers. This involved the partial disassembly of computers and copiers prior to sampling. Thirty (30) samples were collected and analyzed. Four of the thirty samples exceeded the post cleaning target concentration and the geometric mean target concentration was exceeded. All computers, monitors, printers, copiers and fax machines have been removed from the NYCLD space and replaced.

TRC sampled boxed items, such as files, papers, personal effects, in offices and general areas. Twenty-five (25) samples were collected and analyzed. None of the twenty-five (25) samples exceeded the post cleaning target concentration and the geometric mean target concentration was not exceeded. Twenty-two (22) of the twenty-five (25) samples were found to be below the analytical detection limit.

HVAC System The primary components of the HVAC system include the supply ductwork, return ductwork, air handling unit, and ceiling return plenum. Each of these components was sampled for asbestos in surface dust following ASTM microvacuum techniques. TRC sampled the HVAC system after the system was cleaned by ZAR’s initial HVAC cleaning contractor, G & G. Results of HVAC sampling, presented in Appendix A, are organized as follows: Table 2a - Supply Ducts Table 2b - Return Ducts Table 2c - Air Handling Units Table 2d - Induction Units Table 2e - Ceiling Return Plenum

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