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Colorado Backhoe Service Permit# M-2019-074 The Orr Pit December r29, 2017 GEOTECHNICAL STABILITY EXHIBIT This information is presented to address the plan to mine within 200 feet of the structures listed in Exhibit S . The mine depth closest to any structure where no waiver agreement has been obtained is 12 feet . This is a dry mining operation so no water is associated with the mine . There are three structure owners for which there was no damage agreement received. One the Qwest Communications for a communication line was sent two damage agreements, One on 9/22/09 and the second on 9/5/17, neither have been returned. This structures had a Geotechnical Analysis presented and approved in 2009 . One was sent to Carol Baily on the south side and the other was with Keri Joseph on the west side. We used their houses in the following analysis to show that mining will not affect those structures . The information is presented based on the cross sections N- E, W-E, and A-A' shown in this report and using the distances from them to determine the safety factors from the proposed mining face closest to the structure . In Section A-A' the structure is a buried communication line on the west side of 33rd Lane . The floor of the mine in that area will be approximately 4620 and the ground level along the west side of the road is approximately 4610 . The bottom of the excavated area will be approximately 8 feet above and 60 feet east of the structure . In Section W-E the structure is the Keri Joseph house that lies at approximately 4608 and 114 feet west of the permit line. The house is approximately 10 feet below the current yard level that will become the mines floor. As shown on the Reclamation Plan Map the floor of the mine will daylight out on the west side of the mine leaving a level area at the same elevation or slightly above as the road. There will be no excavation below the road elevation and therefor no excavated slope to fail along that side . Both structures west of 33rd Lane lie below the final mine floor. The location of the Cross Sections can be found on the Map Exhibit C-1 - Mining Plan Map. For the Carol Baily house south of the permit area a differ- ent approach was used since the mine floor will be below the elevation fo the house . On this side there is a trench that runs between the fence and the excavation face done in the past . This trench was approximately 6 feet deep or half what it will be when mining reaches the floor. For sake of discussion, the total 12 foot depth was used for the analysis on the pre reclamation time period. At this time the dig line is approximately 5 feet from