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` March 2006 6 053-2442 The wells will be completed at the surface by grouting six-inch diameter locking steel well protectors set in a two foot thick concrete pad. Two-inch diameter PVC slip caps will be placed on the top of the well casing, and the well protectors will be locked with common key locks. 2,2.1 Equipment Decontamination � All drilling equipment and well construction materials (unless pre-cleaned and packaged in the manufacturer's wrapping) including the drill rig, support trucks and trailers, augers, and split-spoon, will be steam cleaned on a decontamination pad upon arrival at the property. All down-hole equipment will also be steam cleaned before drillmg each boring. Augers will be mechanically �� stripped of soil before cleaning. 2.2.2 Well Development and Surveying All monitoring wells will be developed prior to initiation of groundwater sampling. The wells will be developed using a decontaminated submersible pump. � Wells will be surveyed to establish vertical and horizontal coordinates. Top of casing elevations will be surveyed to a marked measuringpoint in the north quadrant of the PVC casing in feet above mean � sea level using a closed level loop. Horizontal positions will be located with a global positioning system or ground traverse to an accuracy of 0.10 feet using the Ramsey County Coordinate system. Tops of casings will be surveyed to an accuracy of 0.01 feet. � 2.2.3 Investigation Derived Waste � Investigation-derivedwastes including soil cuttings and decontamination water will be containerized in 55-gallon drums and staged on-site. Following characterization of the wastes, the drums will be transported off-site to an appropriate facility by a licensed waste management company or aqueous � streams may be discharged to the Publicly Owned Treatment Works in accordance with the MetropolitanCouncilEnvironmental Services regulations. � � � 2.3 Utility Corridor Investigation According to City of Roseville engineering staff, there is a buried water distribution line running north-south along the west side of �-Iamline Avenue. The line is reportedly buried at a depth of approximately 7.5 feet below grade. Based on information gathered from push probes previously installed, depth to groundwater in that area is approximately four and a half to five feet below ground surface. It is unknown at this time if sand or gravel bedding was used to support the buried water line. It is possible that the water line carrido�- may serve as a conduit for the preferential movement of groundwater. � In an effort to determine if the water line utility trench influences local groundwater flow, we propose to advance three push probes on either side of the water line (for a total of six probes). Water samples will be collected from all six probes and analyzed for VOCs. To avoid damaging the water line, City � of Roseville utility personnel will be contacted to locate and mark the water line. The probes will be installed at a distance of not less than two feet from the line marker. Approximate locations of these proposed push probes are shown on Figure 2. Water samples collected from the push probes will be analyzed in an on-site mobile laboratory to evaluate if VOCs have migrated to the north or south � within the utility corridor. 2.4 Groundwater Sampling and Analysis � �