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Fill elevation of the Soil Liner Fill or Synthetic Liner and the real-time elevation of the roving unit. If the pre-placement topography is first adjusted by adding two feet to every grid point, the readout would read "Cut 0.069 ft" if the Drain Cover Fill was being placed 2.069 feet above the synthetic liner. A characteristic time for a reading to be made is on the order of less than 10 seconds. That is, once the roving unit is positioned and "leveled," in about 10 seconds or less the "Cut" or "Fill" reading would stabilize. In addition to the global positioning system operator person who follows along with the dozer, CC&V will have the contractor's laborer and the CQA inspector as a team accompanying the equipment that is pushing Drain Cover Fill material initially onto the liner. Thus, there are three persons in addition to the equipment operator that will assist in achieving a proper thickness as the Drain Cover Fill material is first pushed at or close to the two-foot thickness. During stockpiling of Drain Cover Fill in an area on the liner or when building roads on the liner, if the Drain Cover Fill thickness is three feet or greater, the CQA inspector and one laborer will be present to ensure the three-foot minimum is observed and for prevention of folding of synthetic liner wrinkles. The dozer equipment operator will not be allowed to push material to a thickness less than 2.5 feet, as determined according to the physical markers, unless the global positioning surveying equipment is working with the equipment or unless manual survey equipment is operating with the equipment to produce adequate control information. The global positioning will not be required when the Drain Cover Fill is 2.5 feet or greater. The manual depth markers and observers will control thickness when the thickness will be three feet or greater, as was done in past construction seasons. CC&V has also developed a criterion for illuminating the areas of the Phase II liner where which Drain Cover Fill will be placed at the two-foot thickness during the second shift (night- time) work. CC&V has discussed this subject with the Maxi-lite Company, suppliers of portable light stations, and has determined the candle power of lights should be at least 3 foot candles (at the synthetic liner) to provide adequate luminosity on the liner in the area of Drain Cover Fill being actively pushed. This lighting will provide the OSHA recommended illumination for general construction areas. The single instance of Drain Cover Fill-placing equipment exposing and damaging the synthetic liner in 1995 was one in which the contractor's procedure, which was a procedure that made less use of pipe markers than in 1994, and much less use than scheduled for 1996, occurred at a break in grade. No other such incident occurred in 1995. CC&V has addressed this potential weakness in the monitoring by increasing the grid spacing to 50'x50', along with specific markers at the breaks in slope, which effectively decreases the grid spacing around these areas. Of course, the single incident in 1995 was identified and the adverse effects, where the dozer scrapped down to the liner, mitigated. When the liner was exposed in the entire area of thinner- 7