NYC 9/11 Public Portal Document
Mr. Bernard P. Orlan March 1, 2002
Wipe Samples for Dioxins Page 2
P. S. 234 (Manhattan) ATC Project No. 15-19125-0279
The New York State Department of Environmental Conservation (NYSDEC) has set 0.0006
parts per million (ppm) as the allowable concentration of dioxin in soil. The EPA has
established a residential clean-up goal of 1 part per billion (ppb).
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)
■ ___
3SS
_____
1 st Floor Hallway - east end/DXl U.UUIU
1 st Floor Hallway - west end/DX2 U.(J0U45
Blank/DX3 0.00
The concentrations on indoor surfaces were 0.0012 and 0.00043 ng/m^. These levels are well
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 wipe samples were not collected from this school prior to December 6,
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,
.4 TC ASSOCIA TES INC.
James R. Cohn, CIH, CSP
Regional Manager, Industrial Hygiene Division
Attachment
CITY_21MC100_003057384
NYC-WTC_000196524
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