Dioxin Wipe Sample Report, PS 89M, Feb 2002

NYC 9/11 Public Portal Document

Mr. Bernard P. Orlan Febniary 25, 2002 Wipe Samples for Dioxins Page 2 P. S. 89 (Manhattan) ATC Project No. 15-19125-0297

ATC submitted three (3) wipe samples for PCDDs/PCDFs (plus one blank) to Pace for analysis. Copies of the draft laboratory analysis results are provided in Attachment 1. Samples were taken from areas specified by the parents association consultant. The sample area was one square meter (m2).

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-dioxin (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 sample. The sample locations and the results are shown in the table:

DIOXIN WIPE SAMPLE RESULTS (2, 3, 7, 8 TCDD EQUIVALENTS) January 25,2002

ist Floor Hallway-north/DXl 0.000053 1 st Floor Hallway-south/DX2 0.00042 2nd Floor Hallway-south/DX3 0.00083 Field Blank/DX4 0.00

The concentrations on indoor surfaces ranged from 0.000055 to 0.00083 nanograms per square meter (ng/m^). The dioxin concentrations in these sample are below the NYSDOH guideline.

It is not possible to determine when the 2, 3, 7, 8 - TCDD equivalents detected in these samples were deposited. Dioxin samples were not collected from these locations prior to December 20, 2001.

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

Sincerely, ATC ASSOCIATES n

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

Attachment

CONFIDENTIAL, CITY_21MC100_010729752 SUBJECT TO PROTECTIVE ORDER NO. 2, SEPT. 2008

NYC-WTC_000177714