2019-06-28_REVISION - M1977004 ‎(11)‎

• Permit No: M1977004
• IBM Index Class Name: REVISION
• Doc Date: 6/28/2019
• Doc Name: Request For Amendment To Permit
• From: Homestake Mining
• To: DRMS
• Type & Sequence: AM1
• Email Name: DMC
• Email Name: THM
• Media Type: D
• Archive: No

Homestake Mining Company May 10,2019
Regular(112d)Operation Reclamation Permit Application Package
IRD and perform field-demonstration scale testing during the 2017 field season to validate
"proof of concept" bench and field pilot testing and serve as the basis for full-scale design
and implementation.
• Pitch Project, Permit No. M-77-004, Technical Revision (TR-9) Approval; April 18, 2018
(CDRMS, 2018a). The CDRMS approved the technical revision request to install one
recirculation well in the underground mine workings, installation of up to
10 bore ho les/piezometers in the IRD and TCRD for characterization of source zones,
continued field demonstration of the phosphate-based injections and installation of field
implementation scaled Engineered Treatment Cell (ETC) south of the North Pit Lake.
2.4. Reclamation Summary
2.4.1. General Earthworks
From 1985 to 1993, HMC initiated the process of permanently closing the Mine and performed
incremental reclamation and revegetation activities for various areas. The majority of reclamation
activities were performed in the 1990's, and a summary of general earthwork reclamation
activities is given below:
• 1991 reclamation activities (HMC, 1992).
o Approximately seven acres of the Rock Quarry Site were graded, seeded,fertilized
and hydromulched.
o The report referenced that the low-grade ore stockpiles in the North Dump
(assumed to be the IRD)and TCRD were clay capped in 1986 and 1987, and minor
regrading activities were performed in 1991 to prevent pooling of water.
o Geotechnical to evaluate pit wall and dump stability and piezometer monitoring to
monitor phreatic conditions continued.
o No additional reclaimed area was noted in 112 Annual Report form.
• 1992 reclamation activities (HMC, 1993).
o Approximately 50 acres of the North Dump (assumed to be the IRD) and Rock
Quarry Site received a fertilizer maintenance treatment.
o Approximately 7 acres of the North Dump was regraded and contoured.
o Geotechnical to evaluate pit wall and dump stability and piezometer monitoring to
monitor phreatic conditions continued.
o Seven acres were noted as reclaimed in 112 Annual Report form, with a financial
warranty of$2.263M.
• 1993 reclamation activities (HMC, 1994).
o A temporary low-grade ore stockpile in the North Dump was excavated and
relocated to the previously reclaimed low-grade ore stockpile in the North Dump
(assumed to be the IRD), and approximately 5 acres was capped, covered and
revegetated. Approximately 5 acres of the lowgrade ore stockpile in the TCRD was
covered and revegetated.
o Approximately 10 acres of access road from the TCRD to the Mill Site was
reshaped, scarified and revegetated.
EXHIBIT E-RULE 6.4.5(AMENDED RECLAMATION PLAN) Page 7
HOMESTAKE MINING COMPANY