2011-02-03_REVISION - M2000158 (16)

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Mr. Ebert January 18, 2011 Page 3 CIVIL RES-7)URCES,LLC exceeds the ditch's capacity. The ditch naturally limits the rise of groundwater in this area by intercepting and conveying it to the river if it comes above the ditch invert. This ditch was identified as it will continue to limit the level of the groundwater and is not proposed for any modification in association with the Gilcrest Reservoir project. 9) The applicant proposes a two layered groundwater monitoring plan based on the installation of the slurry walls. What baseline data will be used to determine if the groundwater elevations have been impacted by the proposed mining and reclamation plan? Please submit this baseline data, or commit to installing the proposed groundwater monitoring wells and collecting baseline groundwater elevation data for each monitoring well prior to the installation of the slurry walls. Groundwater monitoring records exist to a limited extent. Other levels are observable at the ground surface or shallow depressions and the operator further commits to installing the proposed monitoring wells and collecting baseline groundwater data prior to the installation of the slung walls. 10) The groundwater monitoring plan states if excessive groundwater mounding occurs, a second underdrain system could be built east of Cells D1 and D2. What does the operator consider to be "excessive" groundwater mounding? Please indicate what specific rise in groundwater elevation would trigger the installation of this second groundwater drain. A two foot rise in groundwater elevation from the seasonal high will trigger the installation of the second groundwater drain, however, the updated surface drains (see Response to Comment 10 below) should ensure that this is not necessary until after the D1 & D2 Cells are constructed. 11) The Division is in the process of reviewing the engineering designs submitted for the groundwater underdrain system. Civil Resources has added surface water control measures in the form of drainage ditches to the water control plan. The ditches will primarily be to promote positive drainage after precipitation events, but will also limit the level of the local groundwater table until mining is complete should the levels rise to this level. Refer Exhibit G. 12) The applicant commits to submitting the collected groundwater data in the annual report for the site. Please submit a plan for notifying the Division once it has been determined a trigger point has been reached initiating the proposed mitigation plan. A 24-hour notification period would suffice. When the Operator notifies the Division a trigger point has been hit, please commit to submitting a plan to the Division indicating when the mitigation measures will be implemented. The operator will submit a schedule of when the mitigation measures will be implemented within fourteen (14) days of the original notification to the Division. 6.4.12 EXHIBIT L - Reclamation Costs 13) The project schedule indicates the overburden for the construction of the embankments will be stripped all at once between September 2010 and February 2011. If this is the case, the Division must hold a bond for the replacement of all the overburden, not just 50% of the embankment material for Cell C1. If overburden stripping is done concurrently with embankment construction for each cell, the Division could hold a bond to backfill only the necessary amount of overburden for a single embankment. If the applicant strips all overburden at once, indicate the amount of overburden stripped. Or, commit to stripping the overburden concurrently with embankment construction and only stripping the amount of overburden necessary at one time for a single embankment cell. If the latter option is chosen, the Division will calculate a bond necessary to re-spread all the overburden for Cell C1. The project schedule has changed due to market conditions. It is now anticipated that the slurry walls and embankments will not be installed for approximately four years and that construction will likely be phased. The applicant commits to submitting a Technical Revision with the updated slurry wall and embankment construction costs and schedule and to posting the appropriate bond prior to construction of these facilities. We respectfully request that the Division recalculate the initial bond requirements with this in mind.