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• <br />PURPOSE AND SCOPE <br />This report presents Yeh and Associates, Inc. proposed monitoring plan for the <br />landslide area west of Terror Creek Reservoir, approximately four miles north-northwest <br />of Bowie Mine #2 near Paonia, Colorado. <br />A landslide has existed along the west side of the Terror Creek Reservoir to the <br />northwest of the western dam abutment since shortly after construction of the <br />impoundment. The Bowie #2 Mine Plan identifies future extraction of coal within one <br />mile of the reservoir. Concerns have been raised by the regulatory agencies with <br />respect to the potential effects of mining related seismicity on the stability of the <br />landslide and the potential for dam overtopping caused by sudden, large ground <br />movements in the area of the slide. <br />• A previous study by Yeh and Associates (#25-196) dated April 5, 2006 and revised <br />November 6, 2006 concludes that this scenario is unlikely due to the anticipated volume <br />of material and the slow speed at which the slope failure is likely to occur. That study <br />included installation of geotechnical instrumentation during the first quarter of 2006, <br />which was the basis for the conclusions in that report. These instruments have been <br />read on a continuous basis since their installation in February of 2006. The <br />inclinometers were read on a monthly basis during the spring of 2006 and then on a <br />quarterly basis since that time based on site accessibility. Measured deformations <br />based on this instrumentation have been insignificant as of the date of this writing. <br />The client has requested that Yeh and Associates develop a plan to employ real time <br />monitoring of the deformation within the soil mass which can !be remotely accessed and <br />that provides the option to alert interested parties in the event that future, significant <br />movements of the landslide occur. This document is intended to constitute an <br />instrumentation plan which conforms to these stated goals. As with most plans, it is <br />likely that some modifications will be required in response to the field conditions <br />encountered during installation.