1. Outline three approaches that an organisation might use to evaluate capital investment projects aimed at improving the environmental performance of the organisation.

2. A paper mill produces large volumes of waste water contaminated with suspended solid material, organic pollutants and metals including arsenic. Before the water can be discharged to a river it is treated to reduce the pollution load. The treatment process produces a solid waste that it sent to landfill. The discharged effluent must be sampled and tested daily to ensure that it complies with the conditions of the discharge consent issued by the water company.

The company's environmental manager is concerned over possible future water shortages leading to restrictions on its use and regulatory pressures to reduce arsenic discharges. She has proposed spending 350 000 on the installation of an additional effluent treatment system that will reduce the overall operating cost of treatment and discharge. In addition, a number of process modifications will be introduced to reduce water consumption.

It is estimated that the following changes in costs will result:

Table 1 Estimated savings from the installation of an addition effluent treatment system Saving (E/year) Effluent treatment chemicals 20 000 Solid waste collection and disposal 10 000 Treatment plant maintenance 7 000 Discharge permit costs 12 000 Water consumption 9 000 Sampling and analytical costs 30 000