SITE INFORMATION AND CORRESPONDENCE CASE 2

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Lynn Forcum 2 - 18 January 2005 • In general, staff does not agree with the interpretation of groundwater flow direction as presented in the Hydrogeologic Review and Request to Use W-4 Report. Staff's interpretation indicates a groundwater mound exists in the 10.1-acre land application area and Wells W-4 and W-5 are downgradient of the land application area. • The unlined irrigation canal east of the 16-acre land application area has inadequately addressed. The presence of the canal can have significant impact on interpretations of groundwater quality and flow direction. • The report does not present an analysis of chemical concentration trends. Such an analysis can be useful when considering if a well is located downgradient of a source area. A 17 August 2004 Request to Use W-4 as Upgradient Groundwater Monitoring Point Report prepared by Kleinfelder uses regional groundwater data and site specific groundwater elevation data to propose use of Well W-4 as the upgradient groundwater monitoring well. That well is not acceptable because it is located in the 10.1-acre land application area and is likely to have been impacted by the wastewater application there. Please submit a groundwater investigation workplan no later than 3 March 2005. The workplan shall present a plan to evaluate groundwater quality in the area of the 10.1-acre land application area including flow direction and quality and discuss the influence on groundwater quality that the South San Joaquin Irrigation District's canal and the wastewater application has or may have on groundwater flow direction and quality. The workplan shall be prepared by a California licensed Engineer or Geologist and shall be consistent with Attachment A,Requirements for Monitoring Well Installation Workplan and Monitoring Well Installation Reports. The RWD will be considered incomplete until the background groundwater quality at the 10.1-acre land application area is characterized. Furthermore, wastewater may not be applied to land application areas that are not described in California Natural Product's existing WDRs. If you have any questions on this request for an RWD and groundwater investigation workplan, please telephone me at(916)464-4616. TIMO R. O'BRIEN Waste Discharge to Land Unit cc: Mike Huggins, San Joaquin County Environmental Health Department, Stockton enc: Form 200 Additional Questions Attachment A NlUelfiOEnrn .J.,., al Nal PmEuclylFartwn 22 Ln 05.d.