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<br />is important to understand the flow window through which the West Pit flows may be exiting <br />to the Rito Seco alluvium. <br />' Currently, there are four monitoring wells located along the pit wall in this area (PW-1, PW- <br />2, PW-3, and PW-4). These installations do not provide sufficient coverage to fully <br />characterize the flow window along this area of the West Pit. Therefore, BMRI proposes to <br />install seven additional monitoring wells averaging approximately 50 to 60 feet (Table 2) in <br />depth to further characterize the flow window from the West Pit to the Rito Seco alluvium as <br />' illustrated in Figure 8. <br />Initial well construction will be completed in the proximity of the observed seepage <br />' downgradient of monitoring well PW-1. This installation will serve a dual purpose allowing <br />for water quality sample collection and hydraulic pump testing using the existing PW-1 as an <br />' observation well to evaluate the cone of influence. Subsequent construction and development <br />of the six remaining wells will be spaced using the results of the initial pump test to properly <br />place the wells to further evaluate the cone of influence and possible future use as interceptor <br />wells to control hydraulic gradients out of the West Pit. Each of the Rito Secp alluvial wells <br />' will be completed through the entire thickness of the alluvial materials. <br />To evaluate potential ground water flow paths through the Santa Fe Formation along the <br />' southwest highwall of the West Pit, two monitoring wells will be installed. These wells will <br />serve to determine if a secondary flow path exists from the pit to the Santa Fe Formation <br />' downgradient of the pit. Each of these wells will be constructed and completed to depths of <br />approximately 100 feet (Table 2). The wells will be pumped tested using existing monitoring <br />' wells in the vicinity as observation wells to evaluate aquifer hydraulic properties and to <br />establish static water levels and water quality data in the Santa Fe Formation. Constant <br />discharge pump tests at each of the wells will be conducted for 4 to 8 hours to establish steady <br />state conditions. <br />' Water quality samples from each of the installed monitoring wells will be analyzed for the <br />parameters shown in Table 3. Each of the wells will be surveyed for both horizontal and <br />vertical control to accurately locate the wells and provide water level elevation data from <br />which potentiometric surface maps can be constructed. <br />1 <br />' 18 <br />1 <br />