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heads will be finished with locking stovepipe -type monuments embedded in concrete pads and protected by concrete -filled traffic posts (bollards). A steel bolt will be embedded in the concrete pad to serve as a reference point for the elevation survey. A representative well construction diagram is presented on Figure 4. 3.4.3 Surveying Surveying of completed monitoring wells will be conducted by the County. Top of casing and ground surface elevations will be surveyed and tied to the existing ground water monitoring datum to the nearest 0.01 foot. The location of the well will be surveyed and identified in the groundwater monitoring network site map. 3.4.4 Monitoring Well Development After placement of the sand pack and prior to placement of the bentonite chips, all wells will be pre -developed using bailing or surging techniques to settle the sand pack and remove fines. The level of the sand pack within the annulus will be measured both before and after the predevelopment process, and additional sand will be added to the borehole, as necessary, to bring the sand pack to the design elevation. After the bentonite chip seal is constructed, the bentonite will be allowed to hydrate for at least one hour before additional well development. At that time each well will be developed using a bailer and surge block and, if necessary, by pumping and surging with a well development pump or bailer until visually clear, non -turbid (approximately 5 NTU) water is discharged from the well, and the temperature, pH, and specific conductivity of discharge water stabilizes. The field geologist will record water quality parameters during development using a calibrated Horiba U52 water quality meter (or similar). Well development and groundwater sampling records will be recorded on a Water Sample p Log Form, and/or on the sampler's daily field report. The information to be included on well development and groundwater sampling records will include: ■ Name of sampler, ■ Total depth of well, casing diameter, and well volume, ■ Starting groundwater level, ■ Time log of groundwater removal, general clarity, temperature, pH, and electrical conductivity, ■ Total well volumes removed, ■ Sample bailing rate, ■ Time of sample acquisition, ■ Final depth to water, and ■ Any problems encountered and their solutions. 11 2011-0115 CHSL EMP Workplan Geo -Logic Associates Revision 2 — January 11, 2012