Chain of custody form for DEP environmental samples, 2001

NYC 9/11 Public Portal Document

Lemongrass Grill occupies 2,351 square feet of space. It utilizes a self-contained re-circulating HVAC system, with no outdoor supply air, that is suspended above the floor in the south end of the restaurant. Return air enters the unit through a grill located in the front side of the unit. The air-handling unit is accessible through access doors on either side of the unit. The unit is enclosed with one-half-inch sheet rock. A supply trunk runs northward through the restaurant with three supply branches. A second source of duct is located adjacent to an exhaust hood for the cooking equipment. This system is separate from the HVAC and supplies makeup air to the hood area. Ambient air is drawn in from a grill above street level to a blower inside the building that leads to a supply trunk. Four supply grills are adjacent to the food exhaust hood.

The Food Exchange is a restaurant that occupies 2,324 square feet of space, running from Cedar Street at the South end through to Liberty Street on the north end. Two side-by-side air handlers that share the supply air duct system are supported above a decorative tinned acoustical ceiling. The supply duct system splits mid-building and runs approximately fifty feet in two opposite directions. A water cooling tower is located outside the building on the building atrium. The air handlers use a common air return with no makeup air being drawn from outside the building. Access to the duct work on the north side of the building must be through the access grill openings, because the ceiling is enclosed in sheet rock. Access to the duct work on the south side is through a suspended ceiling. The ceiling tiles in the area of the duct work and the insulation wrapping the duct work were removed prior to cleaning the ducts. The space from the suspended ceiling to the upper deck, including the grid work, was vacuumed. An isolation wall was fabricated to bar the north side from the south side.

The services of an HVAC consultant were secured to develop site-specific cleaning procedures for the Lemongrass Grill and the Food Exchange, and to stipulate necessary controls, protective measures, and standards for the cleaning and sampling confirmation process. These procedures are provided in Attachment I, HVAC Cleaning Procedures.

The Barber Shop is situated below grade. The unit contains a ductless A/C system with a remote condenser/compressor unit. The condenser/compressor unit is located above the entrance door that accesses Liberty Street. The air handling system and the condenser/compressor unit was cleaned in an effort to remove accumulated residual dust and debris so that the units could be handled for disposal by the building owner.

2.9 Cleaning of Building Exterior/Roof

Cleaning of the building exterior and the rooftop was accomplished and monitored by the NYCDEP. NYCDEP hired an asbestos abatement contractor to accomplish this task. Cleaning of the building exterior was initiated at approximately the same time that cleaning of the interior of the building began. NYCDEP subcontractors were required to vacuum and wash the building exterior twice over a two-day period before acceptable results were achieved.

The building has two roof elevations: An atrium roof at the second floor level, and a roof at the fifth floor level. Four residential compressor/condenser units are situated on the fifth floor roof. These service ductless air conditioning units in the residential apartments. Prior to the study, these units were cleaned by outside contractors. Three commercial compressor/condenser units are situated on the atrium roof of the building. These units service the Chiropractor's Office, the

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