SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

• Please reevaluate the suitability of using metals background data from any location with known or suspected organic contamination. • Please provide references on soil metal concentrations for the region. • Please clarify if the highest chromium concentration of 739 mg/kg was included in the background calculation. Also, please clarify if other metal data from this particular location were used in the background calculation. 19. Section 5.0, "Nature and Extent of Contamination" Section 5 tables do not always accurately identify the contaminants which were analyzed. As an example, Table 5-50 indicates "total metals" were analyzed and all were found to be ND for Site UST-1. However, the supporting text for Site UST-1 (paragraph 5.3.1.3.3) explains that the only metal analyzed was total lead. • Section 5 tables and supporting text should be checked for consistency and corrected, as appropriate. 20. Section 5.0, "Nature and Extent of Contamination" Many Section 5 tables show ND values instead of detection limits. Examples where ND values are shown are tables 5-50 though 5-59. For consistency and clarity, detection limits should be provided on all tables in place of ND values. • Please replace ND values with the detection limits of the constituents analyzed. 21. Table 5-4 Units for "Alkalinity, Total" should be "(mg/L CaCO3)" rather than "(mg/L CACO". Additionally, the "U" after concentration values should be replaced by "<" before concentration values, to be consistent. • Please correct. 22. Paragraph 5.2.2.6 2, Page 5-11, Metals and pesticides in North Pond of SWMU 2 It is stated that metals and pesticides detected in soil samples are considered adequately characterized. As discussed in our general comment, above, a statistical analysis of the Phase I RI results is needed before EPA can concur with such a statement. Additional soil samples from this SWMU may be needed during the Phase 11 RI. EPA 14FEB94 7/10