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Wolf Creek Reserve Groundwater Investigation Work Plan <br />March 6, 2014 <br />be placed in the annulus above the filter pack. The annulus above the bentonite seal will be filled with <br />neat cement grout tremied into place. A secured well protector will be cemented into place above the <br />ground surface to cover the top of the well casings. The wells will be developed using air -lift pumping <br />and surging techniques. The proposed well construction will be similar to that shown in Figure 4. <br />Aquifer Testing <br />Hydrogeologic testing to determine the hydraulic properties of the interburden /coal unit will be <br />conducted by standard packer test methods in the open boreholes prior to construction of the <br />monitoring wells or by slug testing methods after the wells have been installed. The packer test method <br />can be used for testing the overburden if the walls of the open corehole are stable. If the corehole walls <br />are not stable enough to allow packer testing, slug testing will be performed after the monitoring wells <br />are completed and developed. <br />In packer tests, inflatable packers are used to isolate the interval of the core hole to be tested. Single - <br />packer tests are performed by sealing off the core hole at a specified depth and then injecting water <br />into the section of the hole between the packer and the bottom of the core hole. After setting the packer <br />but prior to the testing, the corehole walls in the interval to be tested are cleaned, usually by air -lift <br />pumping as in well development. Typically, single - packer testing is conducted as the drill hole is <br />advanced. As water is injected into the testing interval, the flow into the formation is measured along <br />with the constant water pressure being applied. Based on these measurements, the horizontal <br />hydraulic conductivity is calculated. <br />In slug tests, the water level in the well is raised or lowered suddenly by injection or removal of a slug of <br />known volume, typically a sealed, weighted length or pipe. Pneumatic methods can also be used to <br />effect the sudden change of water level in the well, by sealing the well casing at the surface and <br />attaching a source of compressed air that will be introduced into the well to lower the water level. The <br />recovery of the water level from the sudden change is measured over time and used to calculate <br />horizontal hydraulic conductivity. <br />Water Quality Sampling and Analysis <br />Following well completion and testing, water samples will be collected for field and laboratory water <br />quality analysis. Standard well sampling protocol, as employed for the current ongoing monitoring <br />program, will be used to collect the samples. Field water quality parameters of temperature, pH and <br />specific conductance will be measured when the samples are collected. The samples will be submitted <br />to a certified laboratory for analysis for the water quality parameters listed in Table 2. <br />Table 2. Water Quality Analysis Parameters <br />Chemical: Name <br />Units' <br />Alkalinity as CaCO3, @ pH 4.5 <br />mg /L <br />Bicarbonate as HCO3 <br />m /L <br />Cadmium <br />m /L <br />Calcium <br />m /L <br />Carbonate as CO3 <br />m /L <br />Hydroxide as OH <br />m /L <br />Iron <br />m /L <br />Lead <br />m /L <br />Magnesium <br />m /L <br />Manganese <br />m /L <br />Mercury <br />m /L <br />Molybdenum <br />m /L <br />TETRA TECH 6 <br />