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' PRIVILEGED & CONFIDENTIAL bailer to remove fine grained materials from the well. Approximately three feet of hydrated bentonite pellets were placed on top of the sand pack before grouting the wells. The wells were then grouted to the surface with Portland Cement, using a grout pump and tremie pipe. Following the sealing of the wells, a traffic rated well box and locking cap were installed at each wellhead. A well construction diagram is included in Appendix B. ' Wellhead Surveying On October 28, 1997 the wellhead elevation and location of MW-4 was surveyed by ' Morrow Surveying, Inc. of Sacramento, California. The elevation and location of MW4 was tied into the existing site plan. The newly installed wellhead elevation is included in Table 1. The complete well survey is included as Appendix C. Groundwater Elevation Measurements ' On October 20, 1997 the static groundwater elevations were measured in the four groundwater monitoring wells, by lowering a decontaminated Solinst groundwater elevation probe and measuring the groundwater elevation to the nearest 0.01 foot. Well ' elevation data are included in Table 1. The calculated groundwater elevation indicates that the groundwater gradient is approximately 0.0055 to the northeast. A groundwater contour map is presented as Figure 3. P11 Groundwater Monitoring and Sampling On October 20, 1997 the monitoring wells were purged a minimum of three well volumes ' using a submersible pump. Field parameters were measured during the purging of groundwater with a Hydac conductivity/temperature/pH meter. The pH of the groundwater ranged from 6.81 in MW-1 to 7.05 in MW-3. Groundwater temperature ranged from 20.5 degrees Celsius in MW-4 to 22.8 degrees Celsius in MW-3. Conductivity ranged from ' 860 micro ohms in MW-2 to 2,450 micro ohms in MW-3. The wells were allowed to recharge a minimum of 80% before sampling. Samples were collected from each monitoring well along with a blind duplicate. Water samples were collected by lowering a ' new disposable bailer below the static water level, and raising the bailer slowly in order to minimize agitation of the water sample in the bailer. Water was discharged from the bailer through a bottom discharge valve. Discharge to the sample container was at a rate slow enough to minimize agitation of the liquid. The sample container was filled to the top (from the bottom up) and overfilled leaving no headspace. ' The samples were collected in laboratory-approved glass vials and bottles. Following collection of the samples, they were placed in an ice chest cooled with ice and sent to SPL Laboratories of Houston via overnight courier. Sample handling, transport, and delivery to ' the laboratories were documented using chain-of-custody procedures, including the use of chain-of-custody forms. 1 5 197501 -Stavkron