NYC-WTC_000196730

NYC 9/11 Public Portal Document

Mr. Bernard P Orlan November 25, 2002 Wipe Samples for Dioxins Page 2 Jacob Riis Comm School (P. S. 126 Manhattan) ATC Protect No 15-19125-0343

Each sample was analyzed for sixteen (16) PCDD/PCDF isomers. The results for each isomer were then converted to 2, 3, 7, 8 tetrachloro-dibenzo-p-dioxm (2, 3, 7, 8-TCDD) equivalents by multiplying by an established equivalency factor. This provides a single value (in nanograms) for the analytical results for each sarnple. A copy of the laboratory analysis report is attached. The results are shown in the following table.

DIOXIN WIPE SAMPLE RESULTS 2,3, 7, 8 TCDD EQUIVALENTS - Nanograms per square meter (ng/m^) August 29, 2002 3;YfS)DIC)XINX'ON,GENTRATI(l)N- 1

Mam Lobby / DXl 0.00080

3rd Floor Hall by Room 317/ 0.000076 DX2 4'h Floor Hall by Room 435 / 0.00044 DX3

The New York State Department of Health (NYSDOH) established guidelines for dioxin for the re-occupancy of the Binghamton State Office Building following a PCB fire. The NYSDOH guideline for dioxin on surfaces is 25 nanograms per square meter (25 ng/m^).

The concentrations on indoor surfaces ranged from 0.000076 to 0.00080 nanograms per square meter (ng/m^). The levels found in all of these samples are below the NYSDOH guideline of 25 ng/m2.

It is not possible to determine when the 2, 3, 7, 8 - TCDD equivalents detected in these samples was deposited. Dioxin samples were not collected from these locations prior to these samples therefore a background sample is not available for comparison purposes.

It is our pleasure to provide these indoor environmental services to the NYC Department of Education. If you have any questions about this report, please call (212) 353-8280, extension 212.

Sincerely, ATC Associates, Inc.

James R. Cohn, CIH, CSP Regional Manager Industrial Hygiene Division

Attachment

CITY_21MC100_003042580

NYC-WTC_000196731