VOC sampling locations table for Ground Zero area, Jan 2002

NYC 9/11 Public Portal Document

List of Figures

Figure 1. Figure showing the shrinkages of the restricted zones in the vicinity of Ground Zero over time. For example, the area below Canal Street was no longer prohibited after 9/14, and similarly, the shaded area beneath Chambers Street became available only after 9/27. [Figure extracted from map supplied by City of New York, Emergency Mapping Center].

Figure 2. Particulate matter monitoring sites, including ORD surface sites (A, C, K) on the WTC perimeter, the ORD site at 290 Broadway, and NYSDEC sites located elsewhere.

Figure 3. Spread of dense dust/smoke cloud over all of lower Manhattan and drifting to the E/SE immediately after the September 11, 2001, collapse of the World Trade Center buildings.

Figure 4. World Trade Center plume from intense fires (>1000 °F) during days following September 11, 2001, with high concentrations of both newly formed fine particles from combustion and reentrained coarse particles likely being transported upward by convection processes and being dispersed in the WTC plume over varying NY City areas, depending on prevailing wind directions and speeds.

Figure 5. ORD-modeled WTC plume dispersion on September 11, 2001, at 12 noon. The values indicated by red numerals are hourly PM2 5 concentrations (in jig/m’) measured at pre­ existing NJ and NY State-operated PM monitoring stations in northern New Jersey and New York City. Red, orange, and yellow shading represent most likely areas of plume dispersion (red = estimated dilution to 100* to 500* and dark blue = dilution to <one millionth of pollutant concentration at WTC source).

Figure 6. Satellite photograph of the WTC plume lofting from Ground Zero at 11:43 am EDT on September 12, 2001. Note the very concentrated vertical convection of dust/smoke particles upwards and the flow in a well-defined plume towards the S/SE. (Source: Mandatory Credit: “spaceimaging.com”).

Figure 7. Increased hourly PMj j concentrations measured on September 12 and/or 13 at PS 64, PS 199, Maspeth Library, and PS 274 to the E/SE of WTC, reflecting dispersal of newly formed fine particles from WTC fires and/or fine particles reentrained from the settled dust from initial collapse of the WTC buildings. (PM2 5 data provided courtesy of NYSDEC).

Figure 8. ORD-modeled WTC plume dispersion for September 13,2001 at 9:00 am. Note the increased hourly PM2 5 concentrations depicted in red for PS 64 (166 pg/m^) and PS 199 (100 pg/m’) NYSDEC monitoring stations, consistent with the E/NE direction of the modeled plume dispersion and likely touchdown of the plume at those and intervening sites but not at sites fiirther E, SE, or to the N.

Figure 9. ORD-modeled WTC plume dispersion on September 14, 2001 at 12 noon, indicative of plume flow mainly out over New York Harbor.

DRAFT-DO NOT QUOTE OR CITE iv October 2002

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