Australia– and Botswana-focused copper miner Discovery Metals (DML), has submitted an amended environmental impact assessment that includes the Zeta underground mine and a coal-fired power station at its 100% owned Boseto copper project in north-western Botswana, to the government of Botswana.

According to DML, Botswana’s Department of Environmental Affairs has now moved this application to a four-week phase of public access to the documents, which is a normal phase on route to approval. In parallel with this process, DML continues to liaise with the Botswana government on its plans to construct new power lines into the north-west of the country, which would allow the supply of grid power to Boseto.

The company noted that it has always been DML‘s plan to replace diesel power generation at Boseto with an on-site coal-fired power station or with grid power, adding that this plan had reached an advanced stage, with government recently informing the company that it has completed a feasibility study on this project, and that details would be provided as soon as they became available.

The Boseto power station comprises eight diesel engine/generator sets with total capacity of approximately 21 MW. These were formerly used to power railway locomotives and were all fully rebuilt prior to delivery to Boseto.

The concentrator, which draws approximately 12 MW, can be operated at full design capacity when six of the eight units are operating. A further 5 MW of generating capacity was hired in July 2012 to provide contingency during the power station/concentrator commissioning phase. This capacity was, in effect, the early delivery of the power supply that will be needed at the Zeta underground mine site in Q3/2013.

Meanwhile, DML advised that progress continued on the ramp up of production at Boseto during February 2013, with concentrate production of 3 834 t containing 1 529 t of copper and 63 024 oz of gold the highest monthly copper production to date recorded at the mine.

Furthermore, concentrator throughput was approximately 91% of design rate for the 23 days operated during February, while mining material movements was 2.4 Mt. Mining production, including waste and ore, for February 2013 was 2.4 Mt, which was slightly above the January mining production.

However, the company admits that these results were still lower than planned; adding that the main contributor to lower-than-anticipated production was the lack of blasted stocks at the beginning of the month due to rain.

Looking forward
DML pointed out that mine production, concentrator feed and concentrate production are all expected to increase further towards design rates in March 2013.

It said that the mill continued to demonstrate its overall capability. In the three months since 1 December 2012 the mill has processed 444 kt over 54 operating days at an average rate of 8 222 t/d, which is equal to 98% of design capacity.

The company asserted that it remains confident that the mill will be able to exceed design capacity when sufficient ore feed is available from the mine. The key area being targeted to achieve the required amount of ore feed is the mine, where the company continues to advance initiatives for improving drilling, blasting and truck loading cycles.

DML said the ability to increase blasted stocks in February is indicative of the improvements being made, while cost management and cash generation is also key focus areas. Further, cost management is being assisted by the companys ERP system, which is now fully operational. Concentrate shipments are continuously being expedited to minimise working capital requirements.