Waste fields

Waste Density

Enter the name of the field containing Density values for waste. In many cases this field will be the same as the Density field for ore. There are cases however where blocks in the model will be part ore and part waste (defined by block factors) and the waste will have a distinctly different Density from the ore. This can occur when the ore zone cuts off at a hard boundary with another rock type. In this situation it is necessary to have an additional field in the block model which provides information on the Density of the waste portions of the block.

Waste PCAF

Enter the name of the field containing information on the processing cost adjustment factor associated with putting waste through the mill. In normal cases waste will not be treated in the mill. There are cases however where waste is treated and there is obviously a cost associated with this. For example material in the waste which will result in an acid leaching problem may mean that it waste can be treated in the mill to remove the contaminants for a lower cost than just dumping it. There will be a loss associated with processing such blocks but this may be less than the loss associated with storing the contaminated material. As with the PCAF for ore the values in his field are factors relative to some standard block.

This field only needs to be defined if some of the blocks in the block model are defined as having a Waste Factor (see Block Factors below). If waste is defined in the model but it is not is not to be processed through the mill this field can be left blank. If the PCAF figures are the same for waste and ore the field which defines the ore PCAFs can be referenced here.

Waste MCAF

Enter the field in the block model, which contains information on the mining cost adjustment factors, associated with mining waste. There will be many cases where the cost of mining waste is different to the cost of mining the ore portion of a block. There may be contaminants, which have the potential to cause acid leaching problems, or the waste rock may be of different competence, the MCAF figures for Waste will take this into account.

This field only needs to be defined if some of the blocks in the block model are defined as having a Waste Factor (see Block Factors below). If the MCAF figures are the same for waste and ore the field which defines the ore MCAFs can be referenced here.