2019-03-18_PERMIT FILE - M2018016 ‎(9)‎

• Permit No: M2018016
• IBM Index Class Name: PERMIT FILE
• Doc Date: 3/18/2019
• Doc Name: Adequacy Review Response
• From: Greg Lewicki & Assoc.
• To: DRMS
• Type & Sequence: AM1
• Email Name: PSH
• Media Type: D
• Archive: No

17. On Page D-2, the Applicant states topsoil will be stripped in advance of mining and placed
in a windrow ahead of the mining area. The Exhibit C-2A and C-2B maps indicate topsoil
stockpiled on the pit floor, not in windrows ahead of the mining excavation. Please explain
this discrepancy and update the permit application amendment and Exhibit C maps
accordingly.
Topsoil and overburden stockpile areas identified within the pit are optional locations for the
operator to store excess material. Map C-213 shows the site once mining complete, when there is
no topsoil windrow. At this point, much of the topsoil will already have been placed on
reclaimed slopes and reclaimed flats away from processing areas.
18. On Page D-2, the Applicant states processing fines, overburden (if encountered) and
imported fill may be used as backfill on the slopes. Backfill placed on the slopes will be to
create even shallower conditions then 3H.-1 V. Please comply with the requirements of Rules
3.1.5(2) and(4) -Reclamation Measures-Material Handling regarding the backfilling and
grading of the final reclamation slopes.
See the revised Exhibit D.
19. On Page D-2, the Applicant states reject material from processing will be used in
reclamation and the fines can improve the soil profile during reclamation. Please explain
how the Applicant intends to utilize the reject material to improve the soil profile.
See the revised Exhibit D.
20. On Page D-2, the Applicant states once mining in an area reaches full depth, reclamation of
the mined out portions of the slope will begin with the crest of each cut knocked down with a
dozer to create the final 3H.-1 V reclamation slope. Please describe the pit wall configuration
prior to constructing the reclamation slope. Please include the anticipated volume of
material required to be dozed to construct the final slope.
See the revised Exhibit D.
21. On Page D-3, the Applicant states no pit dewatering will take place as the groundwater
table is well below the bottom of the pit elevation shown on Map C-2. The Exhibit C-1 map
indicates an original elevation of 8480 feet near the location of borehole TH-5. The Exhibit
C-2B map indicates a final elevation of 8350 feet near the location of borehole TH-5 for a
total depth of 130 feet below grade. The depth to groundwater was measured at 90 feet
below grade in borehole TH-05 by the Division during the pre- operational inspection. The
Operator has committed to staying a minimum of two (2)feet above the groundwater
elevation. Please explain this discrepancy and revise the Exhibit C maps accordingly.
Map C-213 shows the total mining depth based on the ground water level anticipated by the
applicant. The applicant will not expose ground water as part of mining; if ground water is
encountered at any point above the elevations shown on the maps, excavation will be backfilled
to two feet and the top of that two feet will become the depth limit of mining.
22. On Page D-3, the Applicant states if the Operator decides to mine below the groundwater
horizon a technical revision will be submitted to the Division to address groundwater
handling. The change in post-mining land use from the currently proposed rangeland to
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