Regulatory and permitting and Economic considerations

Regulatory and permitting considerations. The geographical location of a heap leach project determines to what extent regulatory and permitting issues will dominate its planning, development, operation, and closure. Heap leach projects are impacted by local, state, and federal regulatory agencies. State and local environmental and political issues often dominate the permitting process.

The key environmental concern in permitting a heap leach project is that of cyanide and its containment. The latter applies not only during operation, but also after reclamation.

Economic considerations.

The economic evaluation of a mining project is completed in number of stages, dependent on the information available and the decisions which must be made. In the early stages of development, the major question is ore reserves and evaluations are base on published cost data. Later stages must consider whether the ore body should be developed using heap leaching or conventional milling. Final evaluations and feasibility studies must be done using site specific cost information. Table 1.1 shows a comparison of costs (mining cost and return of investment are no included).

Table 1.1 Comparative Costs

Process	Capital Cost	Operating Costs
CCD	1.00	1.00
Carbon in Pulp	0.68 to 0.75	0.77 to 0.94
Heap Leaching	0.10 to 0.45	0.30 to 0.45

CCD = countercurrent decantation.