ARCHIVED REPORTS SECOND SEMIANNUAL AND 2013 ANNUAL GROUNDWATER MONITORING REPORT

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2.RESULTS FOR SECOND SEMIANNUAL PERIOD 2013 Gauging ' All wells were gauged prior to any sample collection. Depth to groundwater was measured using an electronic water-level meter. The measurements were made to the nearest 0.01 foot from a surveyed measuring point at each well location. Groundwater elevations were calculated by subtracting the depth to groundwater from the surveyed elevation at the surface of the measuring point. Groundwater Sampling After gauging, groundwater samples were collected using HydraSleeve samplers as approved in a November 10, 2011,email from the RWQCB to SFPP. Blaine Tech Services installed the HydraSleeve samplers on March 12,2013, after collecting the samples for the prior semiannual sampling event. , The top of the HydraSleeve samplers were set at approximately the midpoint of the well screens (or slightly below) if the water table was above the screen,or in the middle of the water column (or slightly below) if the water table was below the top of screen. After retrieval,the water from the samplers was transferred into sample containers. Physical parameters (temperature, electrical conductivity [EC], pH, dissolved oxygen [DO], oxidation-reduction potential [ORP],and turbidity) were measured from a portion of the sample as follows,after the sample containers were filled: • Pour water into a Myron L Ultrameter to read temperature,pH, EC, and ORP • Pour water into the Hach Turbidimeter to measure turbidity • Fill a measurement cup and measure DO with a YSI 550 DO Meter Because of insufficient water, samples were collected from M-8 or M-10 with bailers. There were 1.35 feet of water in the bottom of well M-8 and 2.12 feet of water in the bottom of well M-10 during the sampling event, as calculated by subtracting the depth to water from the , total depth of the well measurements on the field data forms (Appendix A). The samples were labeled,placed in a chilled cooler,and delivered to Alpha Analytical, Inc. for analysis. Chain-of-custody protocol was maintained throughout the sample-handling process. Groundwater Analytical Methods Groundwater samples collected from the sampled monitoring wells were submitted to Alpha Analytical,Inc., a California-certified analytical laboratory located in Sparks,Nevada. Copies of the laboratory reports from Alpha Analytical are provided in Appendix B. Groundwater and quality assurance/quality control (QA/QC) samples were analyzed for the following: • Total petroleum hydrocarbons as gasoline (TPHg) and as diesel (TPHd)using United States Environmental Protection Agency (EPA) Method 8015 modified , • Benzene,toluene, ethylbenzene, and total xylenes (BTEX)using EPA Method 8260B The following QA/QC samples were collected: • Duplicate sample from well N-7(labeled DUP-1) • Two equipment blank samples (labeled EB-1A and EB-1B) 2-2 WBG101513183707SC0/HOLT_2SA13_REPORT_FINAL