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the text in Section 3.1.1 to indicate this, and show the calculated <br /> values in comparison to the maximum detected concentrations for each <br /> analyte in a table.. This table should also indicate specifically which <br /> value was selected for use as the exposure point concentration. For the <br /> sake of consistency with the rest of the document, please present COPC <br /> concentrations in a decimal format. <br /> 11. Section 3.1.1 and Section.3.1.2.1, Page 3-1: The text in Section 3.1.1, <br /> Hazard Identification, discusses only concentrations of COPCs, not <br /> hazards. US EPA (1989) defines hazard identification as the "process of <br /> whether exposure to an agent can cause an increase in the incidence of <br /> an adverse health effect" and "characterizing the nature and strength of <br /> the evidence of causation. " Relevant text in Section 3 .1.1 should be <br /> moved to the exposure assessment. <br /> 12. Section 3.1.2.2, Page 3-1: This section does not provide an explanation <br /> of what "toxicity values" represent. For clarity, please provide a <br /> brief explanation of what "toxicity values" represent, rather than <br /> simply presenting slope factors and reference doses in Table 3-1 without <br /> explanation. <br /> 13. Table 3-1: The table does not provide an explanation for the US EPA <br /> classification shown. For clarity, please revise the table to provide <br /> an explanation for the US EPA classification. In addition, because this <br /> is a screening risk assessment, surrogate values should be used where <br /> none are provided for a specific chemical and/or exposure route. For <br /> instance, the respective oral slope factor should be used to <br /> quantitatively evaluate inhalation exposures to DDD and DDE. In not <br /> quantitatively evaluating risk and hazard associated with all pathways <br /> for all COPCs, risks and hazards may be underestimated. However, this <br /> possibility is never discussed in the Report. Therefore, the risk <br /> assessment should be revised to include a quantitative evaluation of <br /> carcinogenic effects via inhalation for DDD and DDE, as well as non <br /> carcinogenic effects from these contaminants for all pathways. <br /> 14. Section 3.1.3.9, Page 3-2: The use of 50 µg/m3 as the respirable dust <br /> concentration in air is not appropriate. Use of the particulate <br /> emission factor (PEF) as outlined in US EPA's Soil Screening Guidance <br /> Technical Background Document (US EPA, 1996) should be used to calculate <br /> concentrations of contaminants of potential concern entrained on <br /> suspended respirable dust particles. Alternately, data from the local <br /> Air Quality Management District could be used as a representative value <br /> for PMI" concentrations typical in the area. Additionally, construction <br /> 5 <br />