Pioneer Releases Alaska Shallow Gas Leases

Pioneer Natural Resources is releasing all existing shallow gas leases in the Matanuska-Susitna Valley acquired as part of its merger with Evergreen Resources, Inc. which closed on September 28, 2004. The released leases cover approximately 235,500 acres and include farm-outs and the Mental Health Trust lease #AK550.185 located east of the Pioneer Unit near the town of Palmer.

As a part of the strategic planning and due diligence associated with the merger, Pioneer decided to relinquish the leases issued under the over-the-counter leasing program and withdraw the exploration license applications made by Evergreen on August 31, 2004. Pioneer believes regulatory certainty is critical to any development program undertaken by the Company.

Scott D. Sheffield, Pioneer's Chairman and CEO said, "We strongly support the State's new gas-only leasing program defined by HB531, and we encourage them to continue the Best Interest Finding process for the Mat-Su."

"We support the efforts of the Mat-Su Borough Assembly to develop a regulatory program that recognizes the State's primacy while at the same time representing the Borough's interests," Mr. Sheffield concluded. "In order to achieve this end, we strongly encourage the MSB Assembly to work closely with the State as they move forward."

In addition to the Mat-Su area leases, Pioneer holds nearly 1,000,000 gross acres on the North Slope and has working partnerships with ConocoPhillips, Anadarko and others. According to Mr. Sheffield, "We are very enthusiastic about the opportunities we're pursuing in Alaska and look forward to a long and prosperous future here."