ARCHIVED REPORTS_SECOND SEMIANNUAL AND 2014 ANNUAL GROUNDWATER MONITORING REPORT

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2.RESULTS FOR SECOND SEMIANNUAL PERIOD 2014 ' The wells were gauged and sampled in the order indicated above (from cleanest to most ' contaminated) to minimize the potential for cross contamination. Figure 2 shows the locations of the wells,and Table 1 presents a summary of the construction details of the wells. Field Methods Field gauging and sampling activities were conducted by Blaine Tech Services,located in ' Sacramento,California. Copies of field notes from Blaine Tech are provided in Appendix A. Gauging ' The wells were gauged prior to 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 5,2014,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. After the sample containers were filled,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: ' • 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 Two of the three wells with insufficient water for sampling had approximately 0.2 feet of , water in the bottom of them. M-8 had 0.17 feet of water and M-10 had 0.21 feet of water in the bottom,as calculated by subtracting the depth to water from the total depth of the well measurements on the field data forms (Appendix A). An attempt was not made to collect , samples from these wells using a bailer because it was impracticable and because this water likely represented water in the end cap at the bottom of each well. The third well,N-8, had 1.74 feet of water in its bottom. An attempt was made to collect a sample with a bailer, ' but a sufficient amount of water could not be retrieved for laboratory analysis. 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 i process. 2-2 ES101214202053SCO