Laserfiche WebLink
J <br />Land Reclamation Division for input and acceptance of <br />the alternatives. <br />After all evaluations were completed, the second alternative was <br />selected. This alternative consisted of excavation and <br />replacement of the toe fill area to form a stabilized base in <br />_ which to place the coal waste, placing coal waste as fill <br />material within the mine bench area, and finally, placing cover <br />material over the coal waste material. <br /> <br />During the alternative selection process, Rocky Mountain <br />Geotechnical was informed by Blue Ribbon Coal Company and by the <br />Mined Land Reclamation Division that the stipulations for the <br />disposal of underground coal waste within the slope stabilization <br />area would require meeting the stipulations set forth in <br />Regulation 4.09 of the Colorado Mined Land Regulations. These <br />regulations require that the mine bench stabilization meet a <br />long-term static factor of safety equal to 1.5 rather than the <br />1.3 criteria originally selected. This information, along with <br />the conditions of the selected alternative, were used in <br />developing a field investigation program for evaluation of the <br />site conditions and preparation of the design model. <br />1.4 RTTF. INVESTIGATIONS ~jjZ ANA •YGIG <br />The site investigation consisted of drilling test borings, to <br />depths of up to 55 feet within the bench area, test pits, in <br />place density testing and installation of piezometers. This <br />4 <br />