SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

%WWI P UBLIC HEALTH S ERVICES oA. ....� SAN JOAQLIN COUNTY JOG[KHANNA Nf l)..M.P.H. Health Officer P.O. Box 2009 (1601 East Hazelton Avenue) •Stockton, California 95201 (209)468-3400 CHRIS RONSON P O BOX 8 ,' ESCALON CA 95320-008 SEP J 8 1992 RE: Escalon Packers SITE CODE: 2150 1905 McHenry Avenue Escalon, Ca San Joaquin County Public Health Services, Environmental Health Division (PHS/EHD) has completed the review of the report "Preliminary Investigation and Evaluation Report" dated July 13, 1992, submitted by Geological Audit Services, and has the following comments. The quantity of data that Geological Audit was able to gather during their assessment work given the limited access to the tank area is commendable. The data gathered from the eight soil borings has adequately defined the lateral and vertical extent of the soil contaminant plume. The report presents the lateral and vertical extent of the plume, the approximate volume of the contaminated soil and a clear description of the subsurface lithology. The recommendation in the report for no further assessment work appears to be warranted at this time. Current remediation technologies commonly used to treat contaminated soils at underground storage tank sites would not be effective or feasible given the unique restraints and conditions at this site. Therefore, the recommendation to leave the contaminated soil in place also appears to be warranted at this time. The discussion presented in the report supporting the decision to leave the contamination in place without threat to groundwater appears to be justified with the data gathered from the assessment work. However, an additional analytical test should be performed on a representative contaminated soil sample that will simulate the solubility of the contaminants to be left in place. The results of this test will give an indication as to the leachability of the contaminants and provide further justification for leaving the contaminants in place without having to monitor the groundwater in the future. The soil sample should be subjected to the extraction procedure used for the waste extraction test as described in the California Code of Regulations, Title 22, Chapter 11, Appendix II, with one modification: Deionized water should be used as the extraction solution in lieu of the citric acid extraction solution. The deionized water extraction solution would better simulate actual site conditions of rainwater or surface water infiltration. After the extraction process, the aqueous extract or filtrate can then be analyzed using the appropriate methodologies to identify the constituents of concern, namely total petroleum hydrocarbons as diesel and oil and grease. A Division of San Joaquin Counry Health Care Services C),