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PERMIT #: M- 1985 -043 <br />INSPECTOR'S INITIALS: TC1 <br />INSPECTION DATE: March 11, 2014 <br />• A review of the original application and the subsequent revisions reveals no Geotechnical Stability <br />Exhibit (Rule 6.5) is on file with the Division. Based on the complex geology observed during the <br />inspection and the presence of houses on the ridge to the east of the mine that were most likely not <br />there when the original permit was approved, the Division is concerned about slope stability. The lack <br />of a Geotechnical Stability Exhibit is cited as a problem on page 1 of this report. <br />• The previous inspection was performed on 2/10/2010. No problems were cited. <br />• The anniversary date is May 6. Annual reports and fees are current through 2014. Both the 2013 and <br />2014 annual reports indicated 40 acres had been affected. <br />• The post -mine land use is forestry. <br />Current Stipulations: <br />Stipulation 2. The applicant shall be required to submit a technical revision, pursuant to the requirements of <br />Rule 1.9, addressing hydrologic conditions and requirements of an approved SWMP, from areas outside the <br />existing 55 acre stormwater runoff assessment area. The Technical revision must be approved by the DMG <br />prior to the Applicant disturbing any acreage outside the existing 55 acre study area. Such revision shall be <br />prepared in consultation with the Colorado Water Conservation Board. <br />Stipulation 3. The applicant will conduct blasting operations only from dawn to dusk and place signs warning <br />people of a threatened species in the area. <br />Bond: ' <br />The currently held bond is $334,000. This bond is for 110 acres of total disturbance and has not been adjusted <br />since Amendment No. 2 (AM -02) was approved in 2001. Significant increases in unit costs since 2001 ensure <br />the current bond is inadequate for the full 110 acres of total affected area. A revised bond estimate <br />calculation summary sheet is enclosed, showing the bond for the full 110 acres of disturbance is $471,605, or <br />$4,287 per acre. Assuming a current disturbance of 50 acres, the current bond allows for $6,680 per acre. As <br />such, the current bond is deemed adequate for the current disturbance. If you would like a complete bond <br />calculation, the Division can provide one upon your request. <br />Summary and Recommendations: <br />1. No Geotechnical Stability Exhibit is on file with the Division. A Technical Revision is required to address <br />concerns with potential highwall instability. A Technical Revision request form is attached for you <br />convenience. The TR shall: <br />a. Provide a geotechnical evaluation of all geologic hazards that have the potential to affect <br />existing and proposed highwalls — Rule 6.5(1); <br />b. Provide engineering stability analyses for proposed final reclaimed highwalls — Rule 6.5(2), and <br />c. Demonstrate through appropriate geotechnical and stability analyses that off -site areas will be <br />protected with appropriate factors of safety incorporated into the analysis — Rule 6.5(3). <br />2. The financial warranty has not been updated in 14 years. A revised 110 -acre disturbance bond <br />estimate summary is attached. Given the current 40 to 50 acre disturbance, the current bond is <br />deemed adequate. <br />Page 3 of 8 <br />