St. Louis, Missouri June 8, 2011

PEC Consulting Group, the consulting arm of PENTA, has signed a contract with Chinalco Peru to provide a feasibility study for the construction of a lime plant to supply this essential chemical to the Toromocho mine concentrator. The Toromocho concentrator is scheduled to commission in August of 2013 and the lime plant will need to be ready by that time. Extensive geological work is being done to locate appropriate sources of limestone as feed for the lime plant. PENTA is a leading company in engineering of lime plants with the support of key lime producers worldwide. Amongst PENTA's lime customers are Lhoist, Carmeuse, Graymont, Southern Peru Copper, Newmont and Barrick.

For additional information about PEC Consulting Group, please visit www.PECCG.com.