The power station was one of the most critical items of construction to be completed during 1971. The 135-megawatt steam power station, situated near the wharf at Anewa Bay , comprised three turbine-generator units rated at 45 megawatts each. It was designed so that two of these units can supply the power requirements of the mine and port areas.

The concentrating process involves three stages of crushing, grinding and flotation. By the end of December 1971, the two gyratory primary crushers and one half of the fine crushing and screening plants were commissioned. In addition, the installation of eight ball mills ground the crushed material in a single stage to the size required for floatation. Water requirements for the concentrator were met by building a pump station on the Jaba River . A pipeline carried the concentrate in slurry form approximately 27 kilometres from the mine site at Panguna to Bougainville Copper's port installation at Anewa Bay .

In 1972, filtering and drying facilities and covered storage were completed at the port, which had been dredged to provide berthing for ships up to 340,000 dead weight tonnes. Copper concentrate was shipped directly from storage into vessels at the 80-metre wharf by belt conveyor. The ninth ball mall commenced operations in 1973.

Mining operations carried out for 365 days in both 1973, 1974 and 1975 were free of major problems. As plant operations improved, copper recovery and concentrate grade increased slightly. However, increased length of hauls tended to reduce overall mine production.

The first of the new Euclid R 170 truck fleet was commissioned in 1976. Pumping operations commenced as the pit bottom was now below the river level and therefore no longer self draining. The concentrator operated continuously throughout the year with only minor stoppages following periods of very heavy rainfall.

The eighth and ninth mine shovel, and the tenth ball mill were commissioned in 1977. Construction of the pit drainage tunnel commenced. Additional secondary crusher and the first of 14 replacement tertiary crushers were commissioned in 1978. The investment in property, plant and equipment stood at K529 million, of which K189 million had been written of, as depreciation, against earnings to date. It was estimated that the current cost of a similar investment would be K1,200 million.

Workshop extensions and the installation of additional workshop equipment undertaken in 1979 provided additional maintenance facilities and technical services back-up. This compensated for the increase in maintenance activity associated with the increasing age of the operating plant.

The Concentrator expansion program commenced in 1981 to compensate for the declining ore grades from the mine. This continued through 1982. In this respect principal activities included the installation and commissioning of the eleventh ball mill in April 1981 and the twelfth ball mill in December 1982. Both mills were commissioned well in advance of the original schedules. Additional support facilities also completed in 1982 included the upgrading of conveyors and provision of additional crushers and screens in the fine crushing plant, the provision of three additional tanks of large capacity (38 cubic metre) rougher flotation cells and the upgrading of water, air and power services. The installation of a large vertical milling machine in the Central Workshop contributed to a successful program of heavy equipment reconditioning with significant savings in the purchase of replacement equipment. Also the Panguna aggregate crusher was upgraded to provide a more reliable source of crushed rock for concrete and haul road surfacing. The two gas turbines installed in 1982 were used to prevent production loss during maintenance on the steam turbines. The cleaner flotation upgrade works were completed during 1983.

A thirteenth ball mill was commissioned in July 198 and another in 1988. These mills operated in a regrind mode to enhance recovery from the orebody. The tailings water reclamation scheme in which water was recovered from the tailing to reuse in the concentrator achieved significant savings. It minimised the need to pump water for the concentrator from a supply 10 km away at the bottom of the Kawerong Valley . Other initiatives included test work on a prototype new generation crusher, improved mining and processing equipment, and the introduction of advanced industrial support equipment in the BCL workshops. The pit drainage tunnel system further reduced costs.

In 1985, the Cap Anamur replaced the previous charter vessel the Zephunte r. Operating costs savings resulted from the new vessel because of a more fuel-efficient engine and automated equipment that reduced the time required in port. The power station was successfully modified to use a waxy residual oil. During 1986 the ability to burn high viscosity oil was reviewed to improve the flexibility of the power station in using cheaper fuels.

A capital program designed to replace certain major items of equipment, achieve marginally increased output and reduce unit costs was commenced in 1987. In total this program was to cost more than K300 million over a period of some four years, and was expected to contribute significantly to the cost effectiveness of operations in the 1990s. By 1988, half of this program had been completed, and six new Euclid R190 haul trucks were commissioned.

From 15 May 1989 until June 1990, all mining equipment was maintained on a ready to mine basis. Sixteen of the 30 Euclid R190 replacement haul trucks had been commissioned with a further six units delivered but not assembled. It was agreed with the suppliers to cancel the purchase of the remaining eight units with no cost penalty.