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O <br /> The road cuts were always excavated as steep as possible. <br /> �- The cut slopes were then modified according to geologic <br /> conditions encountered during the excavation. If the excavation <br /> encountered the bedrock formations, the cut was excavated in <br /> slopes of 1/4 (H) : l (V) , or steeper. Even cuts in colluvial <br /> soils were excavated in steep slopes, frequently steeper than <br /> 45 degrees. Such steep slopes were used in cases where the cut <br /> was excavated in a steep natural slope. Flatter cut slopes <br /> would inevitably increase the excavation yardage and the final <br /> height of the cut. <br /> Inevitably, such road construction creates stability <br /> problems, both in cuts and in fills. Such stability problems <br /> are most common in high cuts in soils because these cuts are <br /> always very steep, if they are located in steep natural slopes. <br /> Low cuts were usually excavated in acceptably flat slopes, and <br /> important stability problems are generally absent. <br /> Any stability problems of roads constructed using this <br /> method are dealt with during the maintenance of the roads. The <br /> maintenance of the roads is required for other reasons than <br /> stability (correction of erosion problems, maintenance of the <br /> road ditch, cleaning of rockfall , snow removal , avalanche <br /> mitigation) . <br /> It should be mentioned that practically without any <br /> exception, all roads were built without any structures, such as <br /> retaining walls, and without the use of bolting or other means <br /> of artificial support of cut or fill faces. <br /> It is evident that roads built by such construction <br /> methods will experience numerous minor or major stability prob- <br /> lems. Our documentation, presented within this report, clearly <br /> confirms this evaluation. <br /> It should also be mentioned that the above described road <br /> construction methods as applied by Mid-Continent during the <br /> last two or three decades are very common in other road <br /> constructions in mountainous parts of Colorado and other parts <br /> of the U.S. They clearly comprise the most economical method of <br /> construction. They are not limited to the coal mining industry <br /> either ; they have been used , with the possible exception of <br /> loosely dumped fills , in the construction of much more <br /> important highways, such as the State of Colorado highways, or <br /> even during the construction of Interstate highways. For <br /> economical reasons, road cuts have been cut at slopes as steep <br /> as possible; stability problems, when encountered, were later <br /> corrected or left to she routine highway maintenance. <br /> 7 . <br /> GE044MRO CONSULTING,INC. <br />