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__`�. .COLORADO LEGACY LAND Exhibit E-Reclamation Plan(Rule 6.4.5): 8 Please provide a detailed plan for removing the master sump for reclamation,including the anticipated Revised as requested. Sump and well abandonment is discussed in Section E.6 disposal location for the materials demolished removed. Exhibit E-Reclamation Plan (Rule 6.4.5): 9 Please describe the existingmine closures(and/or providephotographs of each closure installed in the Revised as requested.Photos of each mine opening closure have been added to Exhibit E as Figure E-1. ( / P ) � q P g g following mine openings:Minnesota Adit,Sunshine Decline,Steve Adit,CV Charlie Adit,and Pierce Adit. Exhibit E-Reclamation Plan (Rule 6.4.5): In comparing the recent mine pool chemistry(2018-present)to the mine pool chemistry during the period Please note that in response to this adequacy review,figure numbers have changed,Figure E-4 is now Figure E-6 and Figure E-7 10 when the mine workings were flooded(2000-2007),the operator states that bulk TDS of the mine water in now Figure E-9.Instead of creating another figure as requested,CLL has added the TDS data to Figure E-6(formerly E-4)to has not changed,indicating the mine is chemically stable.Please provide a graph showing available TDS respond to this request. data compared with Uranium concentration data for these two periods.Additionally,please add TDS data on either the revised Figure E-4 or E-7. Exhibit E-Reclamation Plan (Rule 6.4.5): In its response to the Division's adequacy item#18(e),the operator states the location of return of the RO Please note that in response to this adequacy review,figure numbers have changed,Figure E-3a is now Figure E-5a. concentrate to the mine pre-2017 included a return injection port that included RO concentrate being added to the"open hole"adjacent to the Minnesota Adit(as shown in Figure E-3a).Figure E-3a depicts an "open hole"located in the Steve Adit(directly behind the concrete bulkhead).It is the Division's understanding the Minnesota Adit is located 3 levels higher than the Steve Adit,but does include a"glory 11 hole",in which the operator placed contaminated alluvial material from the valley excavation project. The purpose of Figure E-3a is to show a schematic of the in-situ injections conducted in 2013/2015 not to show an overall view However,this"glory hole"is not shown on Figure E-3a.Please clarify the location of the"open hole" of the mine workings.As depicted,the'open hole'is on the same level as the Steve Adit.However,the access for the open hole referred to in this response. was by way of a temporary pipeline into the Sunshine adit,and this pipeline was removed in 2017 when the new water treatment plant was constructed and the RO concentrate was then injected through the Steve adit bulkhead penetrations into the shafts only.This"open hole"extends several levels from the Sunshine,and by way of personal conversation with the Schwartzwalder mine manager we understand that this"open hole"continued down to at least the 5 level.The Glory Hole was another"open hole"which has now been backfilled.The Glory Hole"open hole"stope was accessed through the Minnesota Adit for the placement of alluvial fill material beginning in 2018 and completed in 2021.This"open hole"i.e.,the Glory Hole was not accessed for any in situ treatment at any time including the in situ treatment conducted prior to 2018. Exhibit E-Reclamation Plan (Rule 6.4.5): On the revised Figure E-7,the operator has included the points in time in which RO reject was injected into Please note that in response to this adequacy review,figure numbers have changed,Figure E-7 is now Figure E-9. the mine,the last of which occurred in 2017.It is the Division's understanding that RO reject is injected 12 into the mine when the water treatment plant is in operation.If this is correct,there should be four In the previous comments,the request was "Please include available mine pool elevation data,dates for in-situ treatments,and 11W additional times between 2018 and 2021 during which,RO reject was injected into the mine.Please date the operation began iniectinn RO reject brine into the mine pool.(emphasis added)"As requested,CLL added the 2 provide clarification on this matter and add additional information to this figure,if needed. occasions(2012/2103 and 2016)that RO reject brine was injected into the mine pool and when the continuous operation and injections started in mid-2107.Rather than clogging up the figure with additional vertical lines,CLL has made a note on the figure to indicate that beginning in mid-2107 the RO reject brine has been continuously injected into the mine pool during operation of the treatment plant.Please note that the text already provided this explanation in the previous version. Exhibit E-Reclamation Plan (Rule 6.4.5): Please describe how re-establishing creek flows across the mine site,as proposed,is expected to affect the In the current dewatered state(150 ft.below the Steve level or greater),hydraulic mechanisms do not exist whereby mine pool 13 mine pool management/water treatment plant operations,if at all. water can exit the workings and migrate towards Ralston Creek and Ralston Reservoir. Therefore,CLL does not expect the re- establishment of Ralston Creek to affect mine pool management or water treatment plant operations.It is possible that the reestablishment of flow in the mine area will allow limited recharge of surface water toward the mine workings,but studies shown during the mine operations showed only minor seasonal effects during the time that the creek had not yet been diverted so CLL ex ects that this additional surface recharge will similarly be minor when the creek flow is reestablished. 14 Exhibit E-Reclamation Plan (Rule 6.4.5): PAGE 4 OF 12 I .