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M. f . ,. . Page 3 All soil cuttings will be stored on-site in 55-gallon Department of Transportation(DOT)approved 17 H drums pending laboratory analysis for appropriate disposal. TASK 3 - INSTALL AND DEVELOP MONITOR WELL The soil borings B-1 will be converted into 2-inch diameter monitor well MW4. The Parker standard operating procedures for well installation and development are included in the Attachments. Figure 2 presents the general well construction details. Two inch inner diameter polyvinyl chloride (PVC)casing with a slot size of 0.020"will be used in the wells..The well screen will extend about 12 ft. into the first water-bearing zone or will be terminated before 40 ft.if a 4 ft,to 5 ft confining layer is encountered. During well development from three to ten well volumes will be evacuated from the well,allowing the pH,specific conductivity,temperature and sediment content of the water to stabilize. The development water will be stored on-site in 55-gallon DOT dnims pending laboratory analysis for appropriate disposal. TASK 4 - GROUNDWATER PURGING AND SAMPLING Prior to groundwater sampling,water level measurement data will be collected from PH groundwater monitoring wells on site. Monitor wells MW-1 through MW-4 will be purged by evacuating.- minimum vacuatingaminimum of three well-cuing volumes of groundwater and will be sampled after allowing the discharge water temperature,specific conductivity,and pH to stabilize.The Parker standard operating procedures for groundwater purging and sampling are included in the Attachments. Monitor wells MW-1 through MW-4 will be sampled with pre-cleaned teflon,stainless steel,or disposable bailers. The samples will be sent under cbain-of-custody to a state-certified laboratory. The purged water will be stored on-site in 55-gallon DOT drums pending laboratory analysis for appropriate disposal TASK 5 - SURVEY WELLS The proposed monitor wells will be surveyed by a state-licensed surveyor to determine the top of casing elevations. These elevations will be used to determine groundwater elevations and estimated groundwater flow direction. TASJK 6 - PUMP TEST Aquifer test:,also referred to as pumping tests,are used to evaluate hydraulic characteristics and piaperhes ofwater-bearing zones and aqurtards. Data obtained from the pump test include hydraulic conductivity(K),transmissivity(I);and specific yield(Sy)for uncon5ned aquifers and K,T,and storage coefficient(S)for confined aquifers. The presence of hydraulic boundaries may also be assessed. The aquifer test consists of pumping One well(probably MW-4)and recording the drawdown in the pumping well and in other nearby observation wells. The constant-rate test is run by continuously maintaining the discharge rate from the pumping well for the duration of the test and monitoring the drawdown in the observation wells with transducers. All gauges,transducers and flow meters will be calibrated prior to use on-site. Parker Environmental services, 4185 Rialto Court, Pittsburg, CA94565-6116 Phone (416) 439-1024 Fax (415) 439-2566