VOC sampling locations table for Ground Zero area, Jan 2002

NYC 9/11 Public Portal Document

establishment of a Web page (http://www.epa.gov/nyrdust2/dustcleanup/ ) and a toll-free hotline (1-877-796-5471 (TTY for the deaf and hard of hearing: 1-800-396-1018)) to take cleanup and testing requests; professional cleanups of remaining unoccupied, unclcaned buildings; evaluation of effectiveness of dust cleanup techniques already used, and testing to establish what the pre-existing levels of contaminants were for Manhattan residences.

Three studies are underway to help develop this clean up plan:

Indoor Air Assessment: Selecting Contaminants ofPotential Concern and Setting Health-Based Benchmarks - The Contaminants of Potential Concern (COPC) Committee of the World Trade Center Indoor Air Task Force is preparing this report to select COPCs and set health-based benchmarks for levels in residences to assist the Pilot Cleaning Effectiveness Initiative and inform the selection of contaminants in the Background Study (these latter two studies are addressed below). Six COPCs have been proposed: lead, PAHs, dioxin, asbestos, fibrous glass and crystalline silica. For each COPC, benchmark screening levels have been established for both indoor air and indoor surfaces, using a three tier approach:

Tier I - Level above which, after elimination of potential indoor sources (combustion by­ products, stored chemicals, etc.), aggressive clean-up action should be taken expeditiously along with follow-up sampling to confirm attainment of Tier III level. Tier II - Range where diligent cleaning should continue, after elimination of potential indoor sources (combustion by-products, stored chemicals, etc.), with follow-up sampling to confirm attainment of Tier III level. Tier III - Level below which the risk is negligible or consistent with the New York City background level found in the Background Study.

Pilot Cleaning Effectiveness Initiative - EPA is conducting a pilot program in an uncleaned/unoccupied building at 110 Liberty Street to determine the effectiveness of various cleaning methods for removing asbestos and other contaminants of potential concern from residential dwellings. EPA has completed sampling for contaminants in 110 Liberty Street, a still-unoccupied building close to the WTC site, in what is a comprehensive test of the effectiveness of various cleanup techniques. Cleaning procedures to be tested include those that were recommended following the collapse of the WTC as well as others that may have been used in cleaning residential units. Comprehensive sampling has been or will be conducted before, during and after the pilot cleanup.

Background Study - Most if not all of the pollutants associated with the collapse of the World Trade Center were present in New York City's environment prior to September 11. To establish a baseline for the presence of these contaminants in affected residences, EPA will collect and analyze samples to look for some of these pollutants in apartments in parts of Manhattan that were not impacted. The Agency will use the data to determine pre-existing or "background" levels of these pollutants in interior spaces in New York City.

DRAFT-DO NOT QUOTE OR CITE 132 October 2002

NYC-WTC_000148973