EPA scope of work review and addendum, April 2002

NYC 9/11 Public Portal Document

Building Facade Clean-up

Work shall be performed by a NYSDOL licensed asbestos contractor with NYCDEP and NYSDOL asbestos certified workers.

The contractor performing the cleaning should be experienced in cleaning building facades.

The clean up area shall be specified ("specified area") by DEP. The area below the facade cleaning shall be covered with a layer of polyethylene sheeting. All debris must be collected for disposal as ACM directly upon removal from the surface. (i.e. All waste must be double bagged in ACM waste labeled bags.) Running water or water runoff on the building facade is not permitted.

Building occupants shall be notified prior to the facade cleaning. Access to the street below the facade cleaning shall be restricted and marked with caution tape. Cleaning shall not be performed during wind speeds greater than 20 mph.

All HVAC systems and air conditioners shall be turned off. All windows shall be closed during the cleaning of the building. Some air conditioners and windows may require sealing with duct tape to prevent water penetration.

In cases where equipment is rigged from the roof: All clean-up activities on the roof must be completed prior to rigging equipment from the roof.

All horizontal surfaces and all windows on the facade shall be cleaned of large bulk material by wetting and hand brushing or scraping with non-metallic bristle brushes or non-metallic scrapers, by wet wiping and/ or by HEPA vacuuming from top to bottom. Only water shall be used for wet wiping and low- pressure washing. Detergents, solvents, additives, and any other chemical cleaning agents are prohibited. The removed material shall be immediately placed into containers (e.g. bags). Windows shall be wet wiped. Free running water shall not be evident during this procedure. Power for HEPA vacuums shall be supplied through ground fault interrupters.

After completion of debris removal, the specified area shall be carefully washed. A low pressure washing technique, moving from top to bottom, shall be employed to minimize water bounce-back. Facades shall be washed with a low-pressure wash not to exceed 250 psi.

At the completion of work, a visual inspection of the abated surfaces and sidewalk shall be performed to verify the absence of visible debris.

Air monitoring shall be performed by an independent NYSDOL licensed third party air monitoring firm with certified workers.

In order to minimize disruption to the public and to the building occupants, it is recommended this work be performed during off-hours.

Page 5 Modified to include Addendum 1 & 2 3/7/2003 Prepared by PT

NYC-WTC 000163675