Houston, Texas, January 6, 2000—El Paso Energy Corporation (NYSE:EPG) announced today that it has entered into agreements for the divestiture of three pipeline systems as required by the Federal Trade Commission (FTC) in its approval of El Paso's merger with Sonat Inc. in October 1999. All three sales, totaling approximately $620 million, are expected to close in the first quarter of 2000, subject to FTC approval.

Duke Energy Gas Transmission has agreed to purchase El Paso Energy Corporation's East Tennessee Natural Gas Company for a total consideration of $386.3 million. The 1,100-mile natural gas pipeline system, with a design capacity of 700 million cubic feet of gas per day, serves the states of Tennessee, Virginia, and Georgia.

CMS Trunkline Gas Company, a subsidiary of CMS Energy Corporation (NYSE:CMS), has agreed to purchase El Paso Energy Corporation's Sea Robin Pipeline Company for $72 million plus a transition service agreement. Sea Robin, a 1 billion cubic feet per day capacity, 445-mile natural gas and condensate pipeline, is located primarily in the Gulf of Mexico offshore Louisiana.

El Paso Energy Corporation has also entered into an agreement with a third buyer for the sale of its one-third interest in Destin Pipeline Company L.L.C. for $160 million. This agreement is subject to the first right of refusal of the interest by El Paso Energy's partners in the venture. The Destin system, with a design capacity of 1 billion cubic feet per day, transports gas from deepwater areas in the eastern Gulf of Mexico.

"The FTC required the sale of these assets in connection with its approval of our merger with Sonat," said William A. Wise, president and chief executive officer of El Paso Energy Corporation. "We are pleased with the terms of these transactions and do not anticipate problems or delays with the FTC approval. The process of merging the two companies into the preeminent natural gas company in North America has been completed, and we are moving forward to realize the opportunities this merger has created."

With over $15 billion in assets, El Paso Energy Corporation provides comprehensive energy solutions through its strategic business units: El Paso Natural Gas Company, Tennessee Gas Pipeline Company, Southern Natural Gas Company, El Paso Field Services Company, El Paso Merchant Energy Company, El Paso Production Company, and El Paso Energy International Company. The company owns North America's largest natural gas pipeline system, both in terms of throughput and miles of pipeline, and has operations in natural gas transmission, gas gathering and processing, gas and oil production, power generation, merchant energy services, and international project development. Visit El Paso Energy's web site at www.epenergy.com.

This release includes forward-looking statements and projections, made in reliance on the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. The company has made every reasonable effort to ensure that the information and assumptions on which these statements and projections are based are current, reasonable, and complete. However, a variety of factors could cause actual results to differ materially from the projections, anticipated results or other expectations expressed in this release. While the company makes these statements and projections in good faith, neither the company nor its management can guarantee that the anticipated future results will be achieved. Reference should be made to the company's (and its affiliates') Securities and Exchange Commission filings for additional important factors that may affect actual results.