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• completely backfill the mine pits in the area to original contour, instead of the current <br />partial backfill proposal. Please provide a location for the additional ground water <br />monitoring wells for these areas as part of your response to the adequacy. The DRMS <br />would like CC&V to collect as much quarterly data as possible prior to affecting acres in the <br />area. <br />Response. <br />CC&V proposes to maintain PGMW-2 (which is dry), and augment the Poverty Gulch <br />ground water information with two additional monitor wells in the thalweg of the gulch. The <br />locations are illustrated on Figure 9 included as Attachment 9, and are identified as PGMW- <br />3 and PGMW-4. Due to difficult access, it may be necessary to relocate one or both of these <br />proposed wells. Each well will be advanced to bedrock, and will be completed with a <br />minimum of 10 feet of slotted screen, sand packed, bentonite sealed to surface, and completed <br />with a steel collar casing. Any water that would be encountered in the wells would be <br />monitored quarterly for water level, field parameters, and the standard CC&V analytical <br />suite. <br />K. The Grassy Valley water balance modeling utilized the GoldSim (version 9.60), the same <br />program used to model the water balance for the valley leach facility. This is a graphical <br />program that is supposed to determine the dynamic deterministic or stochastic simulations. <br />The Division is not even certain this modeling program can accurately predict when a <br />• solution placed in a portions of a lined pad will report to the pregnant solution let alone <br />predict long term water balance for an open natural system with changing mining and <br />backfilling activities. What the Division would like to see are the modules for the program <br />so we can understand the inputs used to get the water balance and if it indeed mimics site <br />specific conditions. <br />Response <br />GoldSim performs stochastic analyses which allow the analyst to ascertain the probability that <br />the conditions of the project will meet any objective. The reliability of the prediction is a <br />function of the precision with which the analyst defines the problem. <br />CC&V provided a copy of the proposed water balance model along with the location where a <br />reviewer version of the GoldSim software could be downloaded to run the working version of <br />the model on September 3, 2008. After opening the model, there are few items to note for <br />DRMS' consideration. Containers (that look like yellow cardboard boxes with the flaps open) <br />are opened by clicking the + sign in their upper left corner. There are about 350 elements in <br />the containers of this (small) model. When the various elements in the containers are visible, <br />you can double click them to see the equation or data in them. To see the time history data <br />generated in the model by those calculations, right click on them and select 'time history' <br />from the options. Selecting 'time history' provides a graph. On the icon bar at the top is an <br />icon that looks like a grid. If this is clicked it will display the data used to generate the graph, <br />which can be copied and pasted it into analysis software (like Excel) or reporting softzi)are <br />• (like Word). <br />L. The long term characterization of the water quality devotes great detail to the impact of <br />sulfide oxidation. What about sulfate salts that may exist on surfaces of already oxidized <br />R7