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DocuSign Envelope ID: 1 AACF3AD-1 B8E-4F1 13-13805-054D9472D4E9 <br /> TRI-STATE <br /> October 20, 2022 <br /> Page 2 <br /> On October 4, 2022, in the early morning, Mr. Tennyson toured the Final East Pit Ditch, South Collection <br /> Ditch, Prospect Pond, the box culvert under State Highway 13, and the adjacent landowners (Ott) calving pasture <br /> to observe what occurred as a result of the October 2nd precipitation event. Mr. Tennyson also visited the <br /> landowner's home at approximately 8:45 AM and initiated discussions with Mr. Ott. Mr. Tennyson committed <br /> to Mr. Ott that Colowyo would commence removing sediment from the culvert and removing the rocks from his <br /> calving pasture as soon as practical and at his direction. Mr. Tennyson stated that the Division would have to <br /> inspect the area first and provide their approval before Colowyo could commence remove the rock and sediment <br /> from the property. <br /> Mr. Trujillo from the Division arrived onsite at approximately 2:00 PM on October 4, 2022, to conduct a <br /> partial inspection of the Final East Pit Ditch, EP 1 and EP2 stock ponds, the South Collection Ditch, and Prospect <br /> Pond in response to Tri-State's notification to the Division on October 3, 2022. Mr. Trujillo ended the inspection <br /> at approximately 5:00 PM. Prior to leaving the mine site, Mr. Trujillo provided verbal approval to Mr. Tennyson <br /> to commence mitigation of the Ott's calving pasture. <br /> Post-Mine Channel and Sediment Control Structures Overview <br /> Final East Pit Ditch <br /> The Final East Pit Ditch(Exhibit 7, Item 14,Part R)is modeled, designed, and constructed for the 10-year <br /> 24-hour event as required by Rule 4.05.3(3). The minimum design parameters as approved require the Final East <br /> Pit Ditch to be constructed as follows: <br /> Side Rip <br /> Approximate Permit Bottom Min. Slope, Rap, <br /> Ditch Name Stationing Description Width Depth H.1 V D50, in <br /> Final East Pit <br /> Vol. 2C Exh. <br /> 1 7-14R <br /> Ditch Reach 0+00 to 11+17 12.0 3.0 2.0 6.0 <br /> Final East Pit <br /> Vol. 2C Exh. <br /> Ditch, Reach 0+00 to 9+17 12.0 3.0 2.0 6.0 <br /> 2 7-14R <br /> In 2011, Colowyo was submitting as-built certifications on all permanent ditches that has been constructed <br /> during the previous year in the annual reclamation report. The entirety of Reach 1 was constructed prior to 2011, <br /> and this was verified through the Division inspections. <br /> A Touchstone Energy <br /> Cooperative 1� <br />