Permit application for roof and facade clean-up cost estimates, 2002

NYC 9/11 Public Portal Document

Roof Clean-Up

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

1. The entire roof shall be considered the work area. All abatement will be performed by NYSDOL licensed contractors with NYC DEP certified workers.

2. A changing area consisting of two adjacent step-off pads located on the ro^/" immediately adjoining the roof entrance/exit. This area shall co. sist of a clean pad and a change pad. The clean pad shall be adjacent to the building interior access way (or at the point of entiy to the roof for exterior access). The change pad sh 11 be adjacent to the contaminated roof areas. Each pad (change pa 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 the exact configuration will be specific to the roof.

3. Workers shall first step from the building interior (or exterior at the point of entry to the roof) 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 booties. The boots thall be wet wiped and HEPA vacuumed prior to leaving the roof. Each worker shall wear a minimum of a half-face air­ purifying respirator equipped with HEPA cartridges.

4. All penetrations at the roof shall be cleaned by wet methods/HEPA vacuum and sealed with polyethylene 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 decomamination practices. Attention shall be paid to limiting unnecessary walking on or disturbance of material on the roof. These personal decent: Inn?ination procedures shall be adhered to strictly in order to minknize 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 HEP/ 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-vacuums).

9. After completion of the above, the entire roof shall be carefully washed.

10. Air Monitoring shall be performed by NYSDOL licensed a Third Party Air Monitoring firm with certified workers. The Third Party Air monitoring firm snail perform a visual inspection to confirm the absence of ACM or debris after the areas are completely dry. Clearance air monitoring shall not be required if all samples collected during the work were found to be below 70 s/mm’.

NYC-WTC_000150849