2019-06-28_REVISION - M1977004 (11)

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Homestake Mining Company May 10,2019 Regular(112d)Operation Reclamation Permit Application Package o The stormwater sediment basin below the Mill Site area was breached and revegetated. o Geotechnical to evaluate pit wall and dump stability and piezometer monitoring to monitor phreatic conditions continued. o A total of 20 acres were noted as reclaimed in 112 Annual Report form, with a financial warranty of$2.263M. • 1994 reclamation activities (HMC, 1995). o A system of diversion ditches was constructed, the details of which were submitted in TR-001 (HMC, 1994b). o Approximately 29 acres of the TCRD was regraded, revegetated and reclaimed. o Approximately 12 acres of the IRD was regraded, revegetated and reclaimed, and an additional 11 acres of the IRD was later revegetated and reclaimed for a total of 23 acres. o Approximately 35 acres of the North Dump was regraded and reclaimed. o Approximately 5.5 acres of the temporary lowgrade ore stockpile footprint in the TCRD was revegetated and reclaimed. o Approximately 24 acres of access roads were reshaped, scarified and revegetated. o Sediment was removed from the Sediment Pond and placed in either of two disposal cells in IRD or TCRD. o Sludge from the RTP was stored in drums and stored in the RTP building. o Geotechnical to evaluate pit wall and dump stability and piezometer monitoring to monitor phreatic conditions continued. Survey monuments located in the North Pit walls were no longer providing reliable data, and a new set of monitoring points were installed. Three inclinometers were also installed. o A total of 116.5 acres were noted as reclaimed in the report. • HMC does not have a copy of the 1995 annual reclamation report, but the 1994 annual reclamation report (HMC, 1995), referenced planning to close the Pinnacle Adit and abandoning wells and boreholes not needed for future monitoring. • 1996 reclamation activities (HMC, 1997). o Approximately 85 acres in the North Pit were regraded to control runoff and provide a suitable surface for revegetation. This regrading included the construction of a ditch lined with clay, fabric and riprap. o Approximately 6 acres of access road from the TCRD and the North Pit was reshaped, scarified and revegetated. o A riprap lined ditch was constructed in the North Dump. o A riprap lined ditch was constructed in the IRD. o Geotechnical to evaluate pit wall and dump stability and piezometer monitoring to monitor phreatic conditions continued. The report noted that a comparison of survey points could not be performed as many monuments were disturbed in the regrading activities. o Forty-five monitoring wells and piezometers were decommissioned in accordance with State of Colorado standards. Piezometers were monitored, and seeps and EXHIBIT E-RULE 6.4.5(AMENDED RECLAMATION PLAN) Page 8 HOMESTAKE MINING COMPANY