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IIF M ring Well MW-1 Installation Work Plan 630 N. California Street Stockton, California July 18, 2013 Page 3 bentonite will be hydrated using potable water. A surface seal of neat cement will be tremied into the annulus of the well and will extend from the bentonite to the ground surface. A generalized monitoring well construction diagram is included as Figure 4, Appendix A. The monitoring well will be completed with locking traffic boxes installed flush with the ground surface. Details of the well construction will be noted on the geologic log, including the depth intervals of the screen, sand pack, and seals. 2.2 MONITORING WELL SURVEYING, DEVELOPMENT, AND SAMPLING Following installation of the monitoring well, the well will be surveyed to determine the location and elevation of the well collar in order to comply with AB2886 (Water Code sections 13195 — 13198). The well collar will be surveyed with a vertical accuracy of 0 .01 foot to a NAVD 88 or NGVD 29 datum, and with a horizontal accuracy of 0 .03 foot to a NAD 83 datum. The measuring point for water-level measurements will be marked on the well collar. Well survey data will be submitted in electronic r deliverable format (EDF) to the State Water Resources Control Board UST site database (GeoTracker). At least 48 hours following construction, the monitoring well will be developed by surging and bailing the groundwater in the well until the discharge water is relatively free of sediment (clear to the unaided j eye) . The monitoring well will be purged until the temperature, electrical conductivity, and pH of the water have stabilized. All well-development equipment will be cleaned prior to use by washing in a solution of laboratory-grade, non-phosphate detergent and deionized water, and by double rinsing with I � deionized water. The purge water discharged from the well during development will be containerized in 55-gallon drums, sealed, labeled, and left on site to await disposal pending results of laboratory analyses. A groundwater sample will be collected at least 48 hours following development of the monitoring well. Prior to sample collection, the static water level in the well will be measured to the nearest 0.01 -foot with a battery-operated, water level meter. A disposable bailer will be lowered into the well to check for floating product, petroleum odor, and/or sheen. If floating product is encountered, the thickness of the LJ product will be measured, but no laboratory sample will be collected. The monitoring well will be purged using a clean, disposable bailer until the temperature, electrical conductivity, and pH of the water have stabilized. At least three casing volumes of water will be purged from the monitoring well. The water purged from the well will be containerized in 55-gallon drums and left on site pending analytical results of the groundwater sample. The groundwater sample will be collected with a clean, disposable bailer and j 1 transferred to laboratory-supplied containers. Each container will be labeled for sample identification and IJ placed in a cooler chilled with ice. Upon completion of the fieldwork, the groundwater sample will be delivered under chain-of-custody procedures to a California-certified laboratory for analyses. 3.0 LABORATORY ANALYSES v The soil and groundwater samples collected from borings will be analyzed for TPH-G, TEPH-D, TEPH- J ✓MO, and TEPH-K by EPA Method 8015B, and for BTEXi/and gasoline oxygenates/additives by EPA Method 8260B. The gasoline additives/oxygenates include methanol, ethanol, TBA, MTBE, DIPE ETBE, TAME, and 1 ,2-DCA and EDB. ✓ // /X 4.0 REPORTING A written report will be prepared detailing the findings of the field work and the laboratory analytical J results. The report will include QA/QC discussion, data validation, conclusions, and recommendations. A draft copy of the report will be submitted to the Client for review prior to finalization. Final reports will be delivered to the Client and SJCEHD. _I A CONDOR d