E-mails 2003 M. Gilsenan

NYC 9/11 Public Portal Document

*2/6/03 Cleaning Procedures J J4 Liberty For

area may be established. Work shall proceed from the 12**’ floor down to the first floor. The use of a remote decontamination enclosure system is acceptable. Prior approval must be received from the NYCDEP for decontamination enclosure system placement and phasing of clean-up activities, if required. (8) An entry/exit log in compliance with the requirements set forth in Title 15, Chapter 1 of the RCNY shall be maintained in the clean room. The site supervisor shall maintain an activity log. (9) Initially, the interior of the elevator shaft, including the top of the elevator car and the elevator pit, shall be HEPA vacuumed and wet wiped to allow for the use of the elevator during the clean up. Once the clean up throughout the building is complete, the elevator shaft, including the top of the elevator car and the elevator pit, shall be re-cleaned prior to clearance air monitoring. (10) Isolation barrier locations (i.e.: wall or ceiling penetrations, windows, vents, doors, etc.) shall be HEPA vacuumed and wet wiped prior to installing two-layers of 6-mil polyethylene sheeting and sealed with tape. Window wells, ledges, guards, etc., that are accessible from the interior shall be cleaned. (11) Negative pressure ventilation equipment (air filtration devices -AFDs) shall be installed and operated continuously 24 hours per day during all clean-up activities. Equipment shall run continuously until clearance air monitoring. A minimum of one air change every 15 minutes shall be provided. When ducting to the outside is not possible, a second negative air unit compatible with the primary unit may be connected in series. (12) Dropped ceilings at functional air plenums shall be removed. Interior and perimeter walls shall be removed to access the interstitial spaces for cleaning. Only one side of each wall shall be removed to access the space. The back of walls scheduled to remain (i.e. tiled bathroom walls) shall be wet wiped and HEPA-vacuumed. For specific information regarding the location of walls to be removed, please refer to the plans. (13) The HVAC Systems and associated ductwork shall be removed and disposed in accordance with applicable rules and regulations. (14) All debris and/or dust shall be misted and double bagged. Accumulation of water is prohibited. Water misting shall be sufficient to wet the material without water accumulations. Caution shall be taken to avoid wetting items that may be damaged by wet methods. An encapsulating agent shall not be applied. (15) All surfaces shall be wet wiped and HEPA vacuumed. Once the initial cleaning is performed, and all surfaces are dry, a second cleaning shall be performed. Surfaces include but are not limited to walls, floors, ceilings, ledges, windowsills, trims, appliances, equipment, personal items, and furnishings. Fireproofing and insulation shall be HEPA-vacuumed only. Care shall be taken to ----- minimize the disturbance of the fireproofing and insulation. The fireproofing is not ACM according to the information provided to the DEP. (16) Surfaces that may not be wet wiped shall be HEPA vacuumed three times or disposed as ACM waste. Disposal of material may not occur without prior authorization by the building owner and/or resident, as applicable. Items identified by residents for cleaning that cannot be cleaned shall be

2 of 4

NYC-WTC_000162862