Black Hills Corp., Rapid City, S.D., (NYSE: BKH) plans to acquire assets in the Piceance Basin of western Colorado from Koch Exploration Co. LLC for an undisclosed purchase price. The transaction is expected to close in the first quarter of 2006. The assets include approximately 40 billion cubic feet of proven gas reserves on leases covering more than 31,000 gross acres (18,000 net; 48% undeveloped). The acquisition also includes 63 producing wells, of which 58 are operated by Koch, and majority interests in midstream and gathering assets. In 2005, production from Koch's interests was approximately 700 million cubic feet of gas equivalent. The acquisition will increase American Naturals' proven reserves by approximately 24% and increase the company's average daily production by approximately 5%.