How one engineer and computer work station design a surface mine

The two SF Coal Corp. engineers planning a 4 million-tpy stripping operation at the new Lee Ranch mine near Grants, N.M. were no novices when it came to using computers. They had been performing feasibility studies with the aid of time sharing computer services to analyze coal qualities of the seams to be mined and to determine the long-term equipment needs. But as the construction of the mine neared completion and the date of the first scheduled coal shipments (October, 1984) approached, it became evident that time sharing had its limitations. Time sharing did help perform long-term planning and to lay out the initial pits. In fact, it led the company to realize that they would need two ongoing pits so as to properly blend the seams to meet coal-quality requirements of powerplant customers. But it was too time-consuming and costly as they reached the point where we needed production scheduling and considerably more graphics.