EPA Special Investigative Audit Report, WTC Site, Nov 2001

NYC 9/11 Public Portal Document

The complete CDD/CDF 2378-specific results for one of the bulk dust samples, AO6351, is listed in Table 11, along with a calculation of Toxicity Equivalence (TEQ) using the USEPA Method 8290, September 1994, Toxicity Equivalency Factors (TEFs). The total TEF adjusted concentration calculated here, 84.9, is slightly different from the NYC Response TEQ (EMPC, ND=0) database value listed for AO6351 as 84.4. At the time of this Draft Report, the source of the difference is still in review.

Table 11. CDD/CDF Results for Bulk Dust Sample AO6351

T,ra.trnn/rnr i ,^663511 l EE TEK ; TEF-^«

if;

2378-TCDD 5.18 1.00 5.18 12378-PeCDD 8.48 0.50 4.24 123678-HxCDD 16.5 0.10 1.65 123789-HxCDD 11.9 0.10 1.19 123478-HxCDD 11 0.10 1.1 1234678-HpCDD 354 0.01 3.54 OCDD 3170 0.001 3.17

2378-TCDF 43.8 0.1 4.38 12378-PeCDF 41.8 0.05 2.09

23478-PeCDF 77.1 0.5 38.55 123678-HxCDF 46.8 0.1 4.68 123789-HxCDF 16.7 0.1 1.67 123478-HxCDF 49.2 0.1 4.92

234678-HxCDF 62.5 0.1 6.25 1234678-HpCDF 165 0.01 1.65 1234789-HpCDF 38.2 0.01 0.382 OCDF 238 0.001 0.238 Total 84.88

Note that a comparison of the CDD/CDF values from these samples at Battery Park on September IS*** with historical CDD/CDF levels in New York City was not performed. This type of comparison maybe useful in determining if future sampling/analysis is wananted.

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