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Extended Site Characierization Report: 7500 West Elevenih Street, Tracy, CA. Page 18 When full, the drums were closed, transported from the well sites and placed in storage on the 7500 West Eleventh Street property until the results of analyses of soil and water samples were available. When the analytical results were obtained, the soil in the drums was classified and, if clean, disposed as clean fill on the 7500 West Eleventh Street property. Soil affected by components of fuel hydrocarbons was loaded into a truck and shipped for disposal at Forward Landfill, a Class 11 disposal facility in Manteca, I ' California. See disposal records in Appendix C. - , 5.8 Well Development { On April 4th and 5th, 2002, the wells were developed by pumping and surging and by bailing a minimum of 10 well volumes from each. The development water was staged on- site in 55-gal. closed-top steel drums. When data was available on the concentrations of analytes of concern in samples recovered from the newly-installed groundwater-quality monitoring wells, drums that contained clean water were emptied by decanting them onto a paved and drained surface on the site. Purge water that was found to be affected by hydrocarbons was decanted into a 1,000-gal. storage tank on the property, where it will be held until sufficient water has accumulated from future groundwater sampling activities to permit its economical disposal at a permitted treatment facility. i` 5.9 Computation of Groundwater Elevations On April 11, 2002, one week following well development, the depth from the top of the casing to the water table was measured using a conductivity meter in each pre-existing and newly-installed well as part of the planned extended site characterization program. That data was used to compute the groundwater table elevations relative to MSL. The measurements and computed elevations are presented in Table 2. -. 5.10 Well Purging After the depths to groundwater were measured, a small-diameter, submersible pump was used to purge each groundwater-quality monitoring well of stagnant water. The pumped water was discharged into 5-gal, pails, each of which was, in tarn, discharged into an open-topped, 55-gallon drum equipped with a securable lid. When the drum was full, it 'j was transported to the 7500 West Eleventh Street property and decanted into a 1,000-gal. storage tank that had been placed on the site for the purpose of storing well development and purge water so that sufficient quantity can be accumulated for it to be economically disposed. During the purging procedure, the temperature, electrical conductivity and pH of the stream of purge water was monitored by periodically checking those parameters using a multi-function electronic meter. Purging continued until all three parameters stabilized, (i.e., variations between measurements were less than 10%) or, in the case of wells screened above the water table, until a minimum of 15 gallons of groundwater had been sic i �