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124th Estates-TR to Application 3 July 9 2002 provides the pit Operator with the flexibility to mine the working face at any angle, and will limit the potential for the Operator to be found non-compliant with a permit condition. In the example illustrated, from a structural protection standpoint, a setback of 40 feet from the Fulton Ditch to the crest of a 1.SH:1V working slope is equivalent to a setback of 95 feet from a near vertical conventional gravel pit mining slope is equivalent to a setback of 107.5 feet from the toe of the slope in a 45 foot deep pit regardless of working face slope angle. The diagram further illustrates that it is logical to establish the enforceable setbacks from the location of the structure to be protected rather than from an easement line. This is because the relationship of the easement line to the actual location of the structure can fluctuate over a wide range. In the example illustrated, the west edge of the Fulton Ditch is only 15 feet from the easement line. In this case, the requirement fora 40 foot setback from the edge of the ditch supercedes the requirement to setback 10 feet from the easement line, as will be case any time the edge of the ditch is 30 feet or closer to the easement line. To summarize, DMG will accept the Applicant's proposed setbacks with the strict condition that the working pit slope not exceed I.SH:1 V and the condition that a minimum setback of 40 feet be maintained from the crest of the 1.SH:1 V pit slope to the edge of the ditch. The DMG suggests that the Applicant consider a permit commitment to maintain a setback measured from the toe of the pit slope rather than from the crest of the pit slope in order to facilitate compliance with the mined land reclamation permit. Item No. 2 -Reclamation Bonden¢ for Clay Liner Installation The Applicant is requesting consideration under the 20 percent bonding option described in the DMG publication "Guide to Specification Prepazation for Slurry Walls and Clay Liners as a Component of a Colorado Mined Land Reclamation Permit," September 2000 (DMG Guide). On page 14 of the DMG Guide it is stated that: The basis of any bonding scheme is predicated on the basis for all reclamation bonding; that at any point in the life of the operation of a pit, the state must hold sufficient bond to implement the approved reclamation plan and establish the approved beneficial post mining land use, The approved beneficial post mining land use for the 224`h Estates Pit is Developed Water Resources in the form of a sealed, clay lined reservoir. At this time, the basic steps required to install the liner and achieve the approved land use consist of: • Complete the excavation of the pit to clay stone bedrock and prepare the keyway and side slopes to receive the clay liner fill. • Strip and moisture condition clay stone to be used as liner fill; place and compact the liner fill on the prepared side slopes. • Install the required wedge of liner cover fill. As of now, there has been no liner installed at the pit, hence there is no installed and tested liner eligible for the 20 percent bonding option. In order to obtain issuance of the permit, the Applicant must provide the full $435,500.00 bond amount required to guarantee completion of the approved reclamation plan. The potential exists to implement the 20 percent bonding option in a stepwise fashion as segments of the lined pit slopes aze completed. Once the Operator completes some percentage of liner and pit slope installation, they may petition the DMG for partial bond release, and if the DMG concurs that the completed section of pit slope has been correctly completed providing a high degree of confidence that leakage criteria will met, 80 percent