Environmental assessment report, 100 Church Street, April 2002

NYC 9/11 Public Portal Document

by the NYCLD. Additionally, TRC inspected the HVAC system to determine the general condition of the system with respect to levels of gross contamination (presence of dirt and debris), and visual observation of the components of the system (i.e., coils, filters, prefilters, condensate pans, etc.) indicating genera] condition/maintenance of system. TRC also conducted dust sampling and analysis, as described in Section 3.4 of this report, within the HVAC system.

3.2 Review of Building Management Response. TRC also met with NYCLD and ZAR to determine what response activities have been conducted to allow for re-occupancy of the building. As is further discussed in Section 4.2 below, ZAR reported taking the following response actions:

• Immediate shutdown of HVAC and post-evacuation securing of the perimeter doors

• Initial sampling for asbestos in the fall of 2001 to evaluate the presence and content of dust

• Interior and exterior cleaning

• Cleaning and flushing of domestic water system

• Cleaning of HVAC system, including fan units, ductwork, risers and return plenum

• Replacement of existing HVAC bag filters with high efficiency filtration, that provides more efficient air filtration

TRC reviewed the procedures used by ZAR in each of these response actions to determine their suitability considering the results of dust/debris sampling conducted by the building. TRC also evaluated these response actions to determine if they met the New York City Department of Environmental Protection (NYCDEP) and New York City Department of Health (NYCDOH) guidance criteria for cleaning up of buildings affected by the World Trade Center (WTC) attack. TRC also evaluated the types of contractors used by ZAR to determine the appropriateness of their certifications and experience for this project.

3.3 Visual Inspection of NYCLD Space

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