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M KLEINFELDER If a clay layer at least 5-feet thick is encountered, the boring will be terminated at that depth below the first encountered water table level. During advancement of the soil borings, soil samples will be collected at 5-foot intervals for lithologic classification. Lithologic classification will be based on the Unified Soil Classification System (USCS). An environmental staff engineer or geologist will log the soil borings. All equipment used in the drilling and installation procedures will be cleaned and/or decontaminated with a steam cleaner or Liquinox cleaning solution. We have included in our estimate the processing of at least one soil sample from each boring for permeability and use in the mounding analysis. Following completion of drilling the soil borings, a clean 2-inch diameter PVC piezometer will be installed in each boring. The soil borings will be advanced approximately 10-feet into groundwater (estimated total depth 25-feet). The wells will be constructed with schedule 40 PVC, a 15-foot long 0.020 inch screened section surrounded by and covered by a sand filter pack (#3), 1-foot thick bentonite transition seal above the filter pack, and grouted to the surface with a cement based grout material. The piezometers will be finished within a monument style (above ground) well vault. The bottom of each piezometer will be constructed with a threaded PVC bullnose cap. Once the piezometers have been installed, they will be surveyed by a State licensed surveyor so the depth to groundwater measurements in the piezometers can be converted to groundwater elevations - used to assess the groundwater gradient. The piezometers will be surveyed relative to a local benchmark. If a local benchmark is not available near the site, the wells will be surveyed relative to an onsite, assumed benchmark with an assigned elevation. 1.3 Piezometer Development Following installation of the well screen and casing, the piezometers will be developed to remove fine silt from the well bore and to effectively increase the hydraulic radius of each monitoring point. Surging along the screened interval of the wells will be performed to settle the sand filter pack. In addition to developing the monitoring wells until the discharge runs relatively clear of fines (fine sand), the discharge will be periodically monitored for pH, temperature, and specific conductance. The develop ment/purge water will be discharged to the land surface in such a manner as not to allow the discharge to enter any surface water body. Task 2 Reportinq Kleinfelder will submit a report with our findings for the installation of the piezometers to Grupe. The initial report will include a description of all field activities, boring logs, development logs, and a graphical representation of the piezometer locations. 71812.H01/ST06R658/JDZ:Iv Page 2 of 4 ©2006 Kleinfelder, Inc. June 22,2006