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Propose <br />Document 5 <br />March 12, 2009 <br />Transit Mix Aggregates <br />P.O.Box 1030 <br />Colorado Springs, Colorado 80901 <br />Attention: Mr. Mac Shafer <br />Subject: Proposal for Slope Stability Evaluation <br />Pikeview Quarry aka Castle Pit <br />Colorado Springs, Colorado <br />CTLIT Proposal No. CS-09-0036 <br />CTL I THOMPSON <br />CTL I Thompson, Inc. is pleased to present this Service Agreement to provide a Slope Stability Evaluation for the <br />Pikeview Quarry, also know as the Castle Pit, in Colorado Springs, Colorado. Based on our conversations with Mr. Mac <br />Shafer, Mr. Jerry Schnable, and a site visit, we understand that Transit Mix Aggregates requires an evaluation of the <br />stability of the failed slope on the west side of the pit to evaluate the slopes current stability, a safe way to improve the <br />slope stability, and provide long-term stable slope configuration for reclamation of the pit. The purpose of our evaluation <br />will be to provide our opinion on the current stability, recommendations regarding the slope stabilization, and potential <br />mitigation methods <br />We envision the stability evaluation being completed in three phases: Phase I Current Slope Stability, Phase II Short- <br />Term Stability Improvements, and Phase II Reclamation Slope Stability <br />Phase I Current Slope Stability <br />The stability of the existing slope will be evaluated based on back calculated parameters from the failed slope using <br />current topography. pre-failure photographs, available subsurface information from previous investigations, site <br />reconnaissance mapping, descriptions of the pit conditions prior to the failure, and our experience. The results of our <br />evaluation will be presented in a written report signed by a Professional Engineer licensed to practice in the State of <br />Colorado. We can discuss our findings with you, other consultants, and regulators, rf desired. We will need an accurate <br />base map of the quarry to use in creating cross-sections for our stability analysis. Likely the safest way to accomplish this <br />is to have the pit and high wall slope scanned using a laser scanner as we discussed with you at your office at the quarry <br />on March 3. 2009. <br />Phase II Short-Term Stability Improvements <br />This work will involve working with pit personnel and other consultants to develop potential methods of stabilizing the <br />portion of the existing pit slope that appears to currently be marginally stable, and selecting a method that is considered <br />safe to improve the stability of the slope. This will likely involve triggering one or more additional slope failures for the <br />slope south of the previous slope failure. Once this portion of the slope has been made safer, then work can commence <br />on completing mining operations and reclamation of the pit. Any additional mining operations will need to be designed and <br />developed to maintain the stabilized slopes in safe configurations for pit personnel. <br />!Q-10 ki;- n !)?li!inci "'Ivd utzl:xa..i 1-pii,ws.::cau1ado 3031:: t' 1"( 5?f3,?3UG I x: ll?-? .F :i:;G I ?rv?w.c.IlF.rou?