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West Pit Fill <br />Final Construction Report <br />These inspection and monitoring requirements as specified under Rule 4.09.1 and 4.09.2 are no longer <br />required for the West Pit Fill as all construction has been completed and the entire West Pit Fill footprint <br />has been Phase II bond released. This report has been prepared to demonstrate that monitoring of the <br />West Pit Fill can be discontinued. The design, instrumentation, and monitoring requirements of the fill <br />are discussed under Volume 5B, Exhibit 19, Section IB. <br />Construction began on the West Pit Fill during the second quarter of 1994, and construction was <br />completed September of 2012. <br />Except when weather conditions made site access impossible, all required, quarterly and annual surveys <br />and inspections have been completed. The final fill certification report was completed on November 8, <br />2018. <br />The West Pit Fill is currently instrumented with nine survey monuments that have been monitored <br />quarterly since installation. The attached graphical data shows the historic movement in elevation, and <br />horizontal displacement. Values presented represent total movement in feet during the monitoring period. <br />A review of the graphical monitoring data shows that all movement has been gradual and are of the <br />magnitude expected for a fill of this size and type, and are within typical survey variation tolerances. <br />On June 25, 1996, the West Pit Fill monitoring well was completed to a depth of 90.5 feet. The <br />inspection reports on file document the various conditions and water levels recorded in this well over <br />time. The Well is located at 348,741.203 N, 1,350,738.504 E and the top of the casing is at elevation <br />6967.85. The 8 3/4" drill hole was completed with a 5" diameter ID steel casing. <br />Attached to this report is Map 1 which shows the limits of the West Pit Fill as well as topographic data <br />from June of 2018. This map also provides a profile down the face of the fill which shows fill thickness <br />relative to the premining condition. <br />I am a Registered Professional Engineer in the State of Colorado. Being familiar with the Colowyo <br />operation, and relying on the information provided to me by Colowyo Personnel, the West Pit Excess <br />Spoil Fill is observed as complete to final design, and deemed stable. <br />