EPA Special Investigative Audit Report, WTC Site, Nov 2001

NYC 9/11 Public Portal Document

Chlorinated Dioxins and Furans (CDD/CPF)

Several different CDD/CDF data sets were found in the NYC Response database, including individual congeners, PCDD/PCDF, Dioxins, and TEQ (toxic equivalents). CDD/CDF isomer or congener-specific samples in the NYC Response database include seven (7) bulk dust samples and six (6) water samples. The bulk dust samples are all from the Battery PK & 2"** Pl location taken on September 16*. The water samples appear to be from various treatment locations of the Newtown Creek STP taken on September 15*. In the water samples, 2,3,7,8-TCDD was not detected with an MDL of 0.01 ng/L (ppt). As of November 16*, no additional CDD/CDF sample results have been found in the NYC Response database.

The results from four (4) CDD/CDF bulk dust samples taken on September 16* at the Battery Pk & 2"“^ Pl sampling site are summarized in Table 10 and Figure 7. At the time of this Draft Report, no additional data has been posted in the NYC Response database. From the bulk dust results, the pattern in CDD/CDF congeners and congener class concentrations in the different samples are highly conelated suggesting a single source. The correlation coefficient calculated between samples AO6353 and AO6351 using the data in Table 3 is 0.9726. In each of the four samples, CDD concentrations generally increase with the level of chlorination. In three of the four samples, OCDD is approximately ten times (lOx) the concentration of total TCDD. The reverse is true of CDF concentrations where the concentration decreases with the level of chlorination. In all four samples, the concentration of OCDF is approximately one-tenth (I/IO) the concentration of total TCDF. The highest reported concentration of 2378-TCDD, the most toxic CDD/CDF, was 5.18 pg/g (ppt).

Comparing the Battery Pk & Z""* Pl bulk dust CDD/CDF profile to nine (9) references in Chemosphere, 1990, Vol 20, which includes CDD/CDF profiles for urban and background soil, paper pulp, incinerator fly ash, and others, the best correlation is with samples from a paper and oil incinerator described by Brown, et. al. (p. 1785 - 1791), with a correlation coefficient of 0.9464.

PCDD/PCDF is also reported for sediment, bulk dust, air, and water samples. All of the sixteen (16) sediment samples were taken at the Foot of Vesey BY CSO M-6 location on September 15*. The highest concentration of PCDD/PCDF reported for the sediment samples was 39.9 pg/g (ppt).

Six (6) PCDD/PCDF bulk dust samples from the WTC location (no sample date listed) were also reported with a high value of 84.4 pg/g (ppt).

From five (5) water samples taken on September 16*, with no location listed, the highest PCDD/PCDF value reported was 0.016 ng/L (ppb).

Four (4) PCDD/PCDF air samples were also reported for samples taken on September 16"" from four (4) different locations on Lower Manhattan. The highest reported PCDD/PCDF value in the air samples was 0.066 ng/m^ from the Location B - Church St & Dey St site. The PCDD/PCDF values are the same as the TEQ values also reported for the same four (4) sites from September 16*.

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