SITE INFORMATION AND CORRESPONDENCE

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In 2004, Mr. Hof contracted with Karsyn Environmental,Ltd.,to continue groundwater monitoring activities. Based on the results and recommendations of the March 2004 monitoring(Karsyn,2004), the RWQCB issued a new MRP(R5-2004-0805)dated August 19,2004(RWQCB,20046),in which the following items were addressed and/or requested for the MRP: • Concurrence to remove ammonium, but maintain fuel constituents and benzene hexachloride in their respective wells, • Concentrations(of any target analytes)detected between the method detection limit(MDL) and practical quantitation limit (PQL) be reported as trace, • Concurrence to abandon all wells at the same time pending a No Further Action(NFA)ruling for the site, provided that water levels be collected in all existing wells for the remainder of the MRP, • An NFA ruling will be considered when it is evident that: o Trends of nitrate and petroleum are declining, o Soil source removal (through phytoremediation) is completed, o Concentrations of benzene hexachloride (b-BHC) are not detected for two consecutive annual sampling events, and o The declining contaminant trends will continue until water quality objectives are met. Mr. Hof then contracted with IDS to perform the annual groundwater monitoring in October 2004 (JDS, 2004) and October 2005 (IDS, 2005). Based on the two annual events of monitoring data, IDS provided recommendations to reduce the requirement for nitrate sampling in selected wells,and requested closure for the petroleum and pesticide aspects of the site. Below, the results of the October 2011 monitoring are provided in Sections 3.0 and 4.0, and recommendations for the forward planning of the project are provided in Section 5.0. 3.0 GROUNDWATER SAMPLING On October 13, 2011,JDS collected groundwater samples from six existing monitoring wells,MW-1 through MW-5 and MW-7 (Figure 2). Each well was visually inspected to observe their physical condition and assess their integrity. Other than minor physical damage to some of the wells, no significant problems were found. To assess the groundwater elevations at the site, the groundwater levels in all monitoring wells were measured to the nearest 0.01 foot prior to sampling (Table 1). Details of water level measurements were recorded on the"Groundwater Sample Forms"presented in Appendix B. Preparation for groundwater sample collection included purging approximately three well-casing volumes of groundwater from each monitoring well prior to sample collection. Monitoring well purging was accomplished by hand bailing with a new disposable polyethylene bailer in each well. While purging the wells, measurements of pH,temperature,and specific conductivity were monitored using a Hanna Tm water quality meter(Appendix B). Once the water quality parameters were deemed to have stabilized and three casing volumes of groundwater removed, the groundwater level within Calfs _Aqui l 3 m smim cm¢wting IV7nm i