BHP Billiton Base Metals recently announced the immediate closure of its in situ copper leaching operations at San Manuel, Arizona, as part of its international copper resource management strategy. The closure of these operations will result in a production cut of 9 000 tons per annum of copper cathode.
(The closure was announced on 15 January in Arizona and is detailed in the Production Report for the quarter ended 31 December 2001.)
BHP Billiton ceased underground mining at San Manuel in August 1999 due to a sustained period of low copper prices. The Group has since managed those operations on a care and maintenance basis. Prior to the cessation of mining operations three years ago, San Manuel produced 100,000 tonnes of copper per annum. Closure ensures the permanent removal of this production capacity.
As a result of the closure of the leaching operations, San Manuel's current workforce will be reduced from 174 employees to less than 50 employees by September 2002. The remaining workforce will be responsible for environmental remediation and security at the mine. Affected employees will receive a comprehensive benefits package, which includes a 60-day extended pay package and extended healthcare and life insurance coverage.
President BHP Copper Inc. John Perry said: "We recognise the impact the closure will have on employees and the community, and we are committed to helping those affected. We will work with local and regional economic support agencies to help employees who may be affected by this decision. We will also honor our commitment to safety and the environment through the closure process."
The underground mine at San Manuel was first established in the 1940s and in 1952 Magma Copper Company constructed the mine, plant and railroads and started developing the community of San Manuel. By 1972, the mine mill was processing more than 60,000 tons of ore per day. The development of the open pit mining operations began in 1985. By the 1990s, the operation included an open pit, solvent extraction-electrowinning operation, an in-situ leaching process and underground sulfide mine. Prior to being placed on care and maintenance in 1999, the San Manuel Mine produced a world record 703 million tons of ore hoisted.
A fact sheet on the closure process is attached.