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the Amendment No. 8 application. However, no reference to the East Cresson Extension mine area is contained within the East Cresson mine section of the "Project Description". General Permit Concerns Each of the three separate mine pit wall slope stability reports addresses the potentially destabilizing effects of water. Water can destabilize the mine pit walls by reducing effective stress on potentially skidding surfaces, and by increasing the driving pressure on the potentially failing rock mass. As Adrian Brown Consultants observed; "The combination of these two effects is that mine wall stability is a strong function of ground water conditions." Mine's excavated beneath a standing ground water table can result in seepage from saturated bedrock into the mine pit. He presence of ground water can, therefore, result in less stable mine walls. Historically the Cripple Creek and Victor areas were mined largely by underground mining techniques. Ground water seepage into underground workings necessitated dewatering and caused roof and rib instability. As in many historic mining areas, dewatering tunnels were driven beneath the ground mass being mined to dewater the ore body and eliminate ground water problems. In the case of the Cripple Creek and Victor mining area three tunnels were driven. Each subsequent tunnel was a thousand feet deeper then the previous one to allow mining to progress deeper in the diatreme. The Moffat tunnel was installed at 9,000 feet above sea level in 1900. The Roosevelt tunnel was installed at B,000 feet above sea level in the 1920's. The Carlton tunnel was installed at 7,000 feet above sea level in the 1940's. These tunnels appear to have been relatively effective in dewatering the overlying rock mass. Each of the three separate mine pit wall slope stability evaluations concluded that because the rock mass is dewatered ground water will not destabilize the pit walls. The past decade's experience in the Main Cresson Mine has verified the analysts' assumption. However, the Main Cresson pit immediately surrounds the Cresson underground workings, known to connect directly to the Carlton Tunnel. The possibility exists that mine pits excavated farther from the dewatering tunnels may encounter ground water conditions. If ground water is encountered by any of the Cresson mine pits, the stability of the effected pit walls will need to be reevaluated by CC&VG in a timely fashion.