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Revised Site Characterization Work Plan <br /> SMH Mountain House,LLC <br /> Page 3 <br /> 4.0 LINED RESERVOIRS <br /> 4.1 RESERVOIR 2—LINER REMOVAL AND BACKFILL <br /> Stormwater will be removed by pumping to Reclamation Area 1 or allowing it to evaporate. Based on <br /> average evaporation rates, the complete removal of accumulated stormwater would occur by mid August <br /> 2009 or earlier. The liner material will be removed and recycled.The excavation will be filled and graded <br /> to the original topographic surface. <br /> 4.2 RESERVOIRS IA AND 113 — SUBSOIL SAMPLING, RISK EVALUATION, RESIDUAL <br /> SOLIDS REMOVAL,LINER REMOVAL AND BACKFILL <br /> 4.2.1 Subsoil Sampling <br /> The project schedule will be managed so that any residual liquids (stormwater) in the reservoirs will be <br /> discharged to Reclamation Area 1 or evaporated prior to soil sampling activities. Based on average <br /> evaporation rates, the complete removal of accumulated stormwater by evaporation would occur by mid <br /> August or earlier in a normal rainfall year. <br /> Twelve composite soil samples (six from under each Reservoir IA and IB) will be collected to <br /> characterize the soil underlying the liners at locations shown on Figure 3, Attachment 1. The FML in <br /> Reservoir I will be cut away to access the subsoil at the proposed sample locations. Surface samples (0 <br /> to 6 inches) will be collected by loosening the soil with a stainless steel shovel. A stainless steel spoon <br /> will be used to place loose soil into laboratory-supplied 4-oz. glass jars. A deeper soil sample(1 foot to 18 <br /> inches) will be collected at each location by digging to approximately 1 foot below ground surface (bgs) <br /> with a stainless steel shovel and using a stainless steel spoon to place loose soil into 4-oz. glass jars. <br /> Depending upon soil conditions, the deeper soil samples may be collected by using a stainless steel hand <br /> auger and transferring the soil directly from the hand auger into laboratory-supplied glass jars. All <br /> sampling equipment will be decontaminated in the field with a solution of laboratory-grade, <br /> non-phosphate detergent and de-ionized water, and rinsed with de-ionized water prior to the collection of <br /> each individual sample. Each jar will be immediately labeled for sample identification upon collection <br /> and placed in a cooler chilled with ice for delivery in accordance with chain-of-custody procedures to a <br /> certified laboratory for analysis as specified in Table 1. <br /> Table 1 <br /> Soil Constituents and Laboratory Methods <br /> Constituents Units I Type Methods I Size of Container Preservatives7month <br /> 6010, <br /> Metals" mg/kg Grab 7471A, 4 oz. (glass) None 7740 <br /> pH Std. Grab 150.1 4 oz. (glass) None <br /> Electrical Conductivity <br /> Saturated Paste(EC) gmhos/cm Grab 120.1 4 oz. (glass) None 28 days <br /> Total Nitrogen mg/kg Grab 351.3/300.0 4 oz.(glass) None 28 days <br /> Note: "Metals include arsenic,cadmium,chromium,copper,lead,mercury,molybdenum,nickel,selenium,and zinc <br /> Units: mg/kg=milligrams per kilogram=parts per million(ppm) <br /> µmhos/cm=micro Siemens per centimeter <br /> oz.=ounce <br /> i.1 CONS%k41W_ ' <br />