Laserfiche WebLink
Jerry We Pages <br /> • March 3,2005 <br /> CONCLUSIONS <br /> The work plan proposes soil vapor sampling conducted consistent with DTSC guidance <br /> (DTSC &LARWQCB, 2003; DTSC,2004);therefore the baseline data should be <br /> acceptable for use in a predictive indoor air human health risk assessment. HERD <br /> recommends the above modifications to the work plan to obtain adequate soil vapor and <br /> geotechnical data for a baseline human health risk assessment of indoor air for the <br /> current apartment dwellers within the zone of influence of the SVE system prior to start <br /> up of the SVE system. To expedite risk evaluations in the apartments' area,the <br /> responsible parties should address the L& M OU as two areas of concern(AOCs), <br /> preparing a separate HRA using a hot spot approach for each AOC. One AOC being the <br /> Della View Apartments(the apartments'area)and the second AOC being the <br /> undeveloped area. HERD recommends filling the remainder of the HHRA data gaps in <br /> the apartments' area, consistent with HERD's February 2, 2005 memorandum, as soon <br /> as feasible and irrespective of the operational status of SVE system. RERD continues <br /> to recommend:(1)collecting supplemental data to address all data gaps; (2)submittal of <br /> the complete data sets as well as the data sets proposed for use in the HHRH in electronic <br /> format to ensure site characterization Is adequate for HHRA purposes:and (3)preparation <br /> of the revised HHRH consistent with comments provided in HERD's September g,2004 <br /> and September 28,2004 memoranda using the DTSC/HERD approved HHRA data set. <br /> REFERENCES <br /> • DTSC, 2003. Advisory—Active Soil Gas Investigations. January28, 2003. <br /> DTSC, 2004. Guidance for the Evaluation and Mitigation of Subsurface Vapor Intrusion <br /> to Indoor Air. December 15,2004. <br /> Reviewed by: David L. Berry, Ph.D. <br /> Senior Toxicologist <br /> Science, Pollution Prevention and Technology Program <br /> Human and Ecological Risk Division <br /> • <br /> 050303JL.dw <br />