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COLORADO LEGACY LAND
<br /> IN
<br /> III
<br /> 0 The Division of Reclamation,Mining and Safety(Division)has completed its preliminary adequacy review Please see responses to specific comments below.
<br /> of your Amendment Application(AM-6)submitted for the Schwartzwalder Mine.All comment and review
<br /> periods for the application began on July 29,2021,when the application was called complete for filing
<br /> purposes.The decision date for the application is set for December 26,2021.
<br /> The review consisted of comparing the application content with specific requirements of the Mineral Rules
<br /> and Regulations of the Colorado Mined Land Reclamation Board for Hard Rock,Metal,and Designated
<br /> Mining Operations.The Division has identified adequacy items in the application requiring clarification or
<br /> additional information.These items are identified below under their respective exhibit heading,and are
<br /> numbered sequentially.
<br /> Exhibit E-Reclamation Plan (Rule 6.4.5): The detailed reclamation plan is provided in Exhibit E of AM-05 and is updated herein with AM-06 as Exhibit F.Figure F-1 which
<br /> illustrates the reclamation plan map.Information in these exhibits correlates to the bond estimate presented in Exhibit L of
<br /> Please provide a detailed reclamation plan for all affected lands at the site,which correlates with the AM-06.
<br /> 1 reclamation plan map provided in Exhibit F and the bond estimate provided in Exhibit L.Please be sure
<br /> this plan addresses all surface disturbances and mine openings,mine pool management,and water
<br /> monitoring.This plan must comply with all applicable requirements of Rule 3.1-Reclamation Performance
<br /> Standards and Rule 6.4.5-Reclamation Plan.
<br /> Please provide a cross-section of the site showing the mine workings,mine pool level (at 150 feet below Exhibit G of AM-06 has been revised to provide two updated figures,Figure G-1 and Figure G-2.This information was initially
<br /> Steve Level),adjacent monitoring wells with screened intervals and measured water levels,Ralston Creek provided in Exhibit G of AM-05.These figures are an update to Figure S.Cross Section Showing Mine Workings,Faults,
<br /> 2 channel,and any significant fracture/fault systems and other potential groundwater migration pathways Underground Water Sample Locations of the Schwartzwalder Mine,Hydrologic Evaluation of Mine Closure and Reclamation
<br /> that intersect the mine workings. (Whetstone Associates,2007) and Figure 1-1 of the Schwartzwalder Mine,Environmental Protection Plan (Whetstone Associates,
<br /> 2007).
<br /> Please provide a plan view map of the site showing the extents of the mine workings,adjacent monitoring This information is presented on AM-06 Figure E-2. Additional discussion on the figure and the physical stabilization of the mine
<br /> well locations (shown in the cross-section requested above),Ralston Creek channel,any significant pool is provided in the memo included as Appendix 3 of AM-06.
<br /> 3 fracture/fault systems and other potential groundwater migration pathways that intersect the mine
<br /> workings,and the point at which any such pathways intersect the creek system between the mine site and
<br /> Ralston Reservoir.
<br /> On page 13,the operator states"Upon completion of the alluvial valley excavation project,this bypass The referenced text is consistent with the mine reclamation plan. The 18-inch diameter,approximately 4,000-feet long,HDPE
<br /> pipeline shall be removed,and Ralston Creek will flow through its natural channel".If this is part of the diversion pipeline was designed and constructed by Wright Water Engineers under Technical Revision 18 (TR-18). The
<br /> proposed reclamation plan,additional details are needed.Please provide approximate dimensions for the diversion pipeline was constructed in 2011 to isolate clean water flowing in Ralston Creek from mining-impacted alluvium,and
<br /> pipeline to be removed,and any other associated structures/features which will require demolition and/or to help dewater the alluvium for excavation work. CLL intends to remove the diversion pipeline and two bollards which hold the
<br /> removal(e.g.,bollards,upgradient cutoff wall,berms).Additionally,please describe any proposed changes pipeline in place.
<br /> 4 to the creek channel for final reclamation.After the excavation project is completed,how will the valley
<br /> floor be reconfigured to establish positive drainage to the creek?Lastly,with the removal of alluvial After excavation is complete,CLL shall reclaim consistent with the current Reclamation Plan Map (Figure F-1).
<br /> groundwater monitoring wells and sumps in the valley during the excavation project,how will the
<br /> operator continue to monitor potential impacts to the creek and alluvial groundwater system once creek For continuity in the environmental monitoring data set,CLL will continue to utilize surface water sampling stations BPL and
<br /> flows have been re-established across the mine site? AWD and groundwater sampling wells in the quarterly monitoring network after the excavation work is complete. This will
<br /> allow project stakeholders to have continuity in the data set that demonstrates that impacts to the stream do not cause
<br /> exceedance of the relevant water quality standards at BPL.
<br /> On page 14,the operator states"Maintaining the mine pool below the regulatory limit(150 feet below Please see responses to specific comments below.
<br /> Steve Level) has led to (i) establishing a hydraulic gradient away from Ralston Creek in the permit area,
<br /> 5 and(ii) reducing the exposure of wall rock to oxygen,which minimizes uranium oxidation in the workings
<br /> and translates to less mobile uranium to treat".The Division has the following comments regarding this
<br /> statement:
<br /> The"regulatory limit"for the mine pool was set by the modified Board Order,dated October4,2012,which Additional information collected by CLL(2018 to present) is provided in section E.5.1 Physical Stabilization of the Mine Pool
<br /> required the operator to"reinitiate mine dewatering and water discharge treatment sufficient to bring the Demonstration of AM-06.This discussion validates that the mine pool is not interacting with Ralston Creek either on the mine
<br /> 5a mine water table to a level at least 150 feet below the Steve Level,and sufficient to reestablish a hydraulic site as monitored by MW-18,or through a pathway hypothesized along the Schwartz trend to the east as monitored by MW-15.
<br /> gradient away from Ralston Creek".While the regulatory level was initially set at 500 feet below Steve
<br /> Level in the Board Order dated August 11,2010,it was modified as a result of information provided in AM-
<br /> 4(approved on April 29,2013 ,which indicated dewatering to the level of 150 feet below Steve Level
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