Mariner to Expand Onshore Presence with Edge Acquisition

Mariner Energy has agreed to purchase the subsidiaries and operations of Edge Petroleum Corporation in a transaction valued at approximately $215 million after anticipated purchase price adjustments. Mariner expects the transaction to close by December 31, 2009, with an effective date of June 30, 2009. The transaction has been approved by the bankruptcy court in which Edge's Chapter 11 case is pending, subject to any appeals. Mariner will utilize its revolving credit facility to fund the acquisition.

Transaction and asset highlights include:

• Edge reported year-end 2008 estimated proved reserves of 124 billion cubic feet of natural gas equivalent (Bcfe), all fully engineered by independent reservoir evaluation consultants, approximately 90% by Ryder Scott Company, L.P. Mariner estimates that at December 31, 2009, the properties include approximately 106 Bcfe in estimated proved reserves, 70% of which are developed (72% gas, 28% liquids).
• More than 80% of the reserves are located in South Texas, establishing a new core area for Mariner. Approximately 45% of the reserves are based in the Flores/Bloomberg field in Starr County.
• Third quarter 2009 daily production from the assets averaged approximately 29 million cubic feet of natural gas equivalent.
• The assets also include nearly 70,000 net undeveloped acres, primarily in Texas and New Mexico.
• Mariner structured the transaction to preserve certain tax attributes of the Edge subsidiaries, including the tax basis of the assets acquired and net operating losses. Mariner estimates the potential value of these tax attributes to be approximately $95 million.

"Consistent with our stated strategy of expanding our onshore presence, the Edge transaction establishes a new core area for the company. Based on year-end 2008 results, the combination results in more than half of Mariner's proved reserves being onshore. The economic metrics of the transaction are compelling, potentially further enhanced by the preservation of the tax attributes. We expect the assets to generate excess cash flow while self-funding future development costs. We look forward to welcoming the Edge personnel to our company," said Scott D. Josey, Chairman, Chief Executive Officer and President of Mariner.