5 2 WILLIAM STREET Bl. 40Lot: 16/1001006 52 WILLIAM STREET 1001006, 40/16

NYC 9/11 Public Portal Document DEP ECB Fax:212-361-1724 Rug 9 2002 03:59 P.11

Roof ClemxD Application: This procedure utilizes wet methods and careful hygiene with asbestos containing material (ACM). protocol for cleaning roofs contaminated

1. The entire roof shall be considered the work area for entry/access performed by NYSDOL licensed contractors with NYC DEP certified determinations. All abatement will be workers. For non-gravel or stone covered roofs with localized accumulations of visible debris, the clean-up areas shall be specified ("specified area") by DEP.

For gravel/stone covered roof surfaces, the entire roof shall be included.in the specified roof area far clean-up. The gravel/stone shall be taken to a clean-up staging area on the roof and washed. Water shall be collected, filtered, and discharged into the drain/sewer as applicable.

2. A changing area consisting of two adjacent step-off pads located on the roof immediately adjoining the roof entrance/exit This area shall consist of a clean pad and a change pad. The clean building interior access way (or at the point of entry to the roof for pad shall be adjacent to the exterior access). The change pad shall be adjacent to the contaminated roof areas. Each pad (change pad and clean pad) shall consist of two layers of 10- mil reinforced plastic on the roof/access way surface and shall be large enough to facilitate changing and decontamination as described herein. A minimum of 4' x 4' is recommend, though be specific to the roof. the exact configuration will

3. Workers shall first step from the building interior (or exterior at the point of entry to the root) directly onto the clean pad On the clean pad, each worker shall be double suited with, disposable coveralls, plastic booties, gloves, and head coverings. Rubber boots may be used instead of the plastic wiped and HEPA vacuumed prior to leaving the roof. Each booties. The boots shall be wet worker shall %vear a minimum of a half-face air- purifying respirator equipped with HEPA cartridges. 4. All penetrations at the roof within 10 feet of the specified roof area wet mcthods/HEPA vacuum and scaled with 6-mil polyethylene included in the. cleani-up shall be cleaned by sheeting. 5. Roof cleanup shall begin at the entrance/exit and proceed in a path working away from the entrance/exit. Water shall be the primary engineering control to minimize the potential for fiber release. 6. Roof surfaces shall be wetted and then wet cleaned using wet wiping techniques with water, mops, rags, brushes, etc. HEPA vacuuming may also be used as alternative to or in combination with wet cleaning. 7. Throughout the procedure, all personnel entering or existing the roof shall observe the personal decontamination practices. Attention shall be paid to limiting material on the roof. These personal decontamination unnecessary walking on or disturbance of procedures shall be strictly adhered to, in order to minimize the potential for spreading contamination to the interior of the buildings. 8. Solid nonporous objects, such as metal patio furniture, plant potters, and plastic furniture cushions, shall be wet wiped with damp rags. Wooden objects such as decking shall be HEPA vacuumed, wet wiped, and lightly brushed with a bristle brush utilizing simultaneous misting and local HEPA exhaust, Woven materials shall either be disposed as ACM or bagged and removed off-site for proper laundering in accordance with 29 CFR 1901. 1001. Potted plants with visual contamination should be disposed as ACM waste unless the owner requests decontamination. Potted plants will be repeatedly rinsed, and provisions shall be made to catch the runoff water (i.e. into ACM disposal bags or by using rags and HEPA wet-vacuuoo~s). 9. After completion of the above, the specified area roof shall be carefully washed.

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NYC-WTC 000110184