HOUSTON, TEXAS, July 22, 2004—Wyoming Interstate Company (WIC), a subsidiary of El Paso Corporation (NYSE:EP) and part of the company's Western Pipeline Group, announced today that it has received binding bids for 350 thousand dekatherms per day of transportation capacity on its proposed Piceance Lateral Expansion project as part of a recently announced open season. The Piceance Lateral Expansion Project will involve the construction of a 143-mile, 24-inch pipeline from the Piceance Basin in northwest Colorado to the WIC and Colorado Interstate Gas (CIG) pipelines near Wamsutter, Wyoming. The company is seeking to determine whether there is additional interest that would necessitate increasing the scope of the expansion.

"The Piceance Lateral Expansion represents the much-needed development of critical infrastructure for one of the most prolific natural gas supply sources in the United States," said James Cleary, president of El Paso's Western Pipeline Group. "This expansion and the Cheyenne Plains Pipeline project demonstrate our commitment to providing transportation solutions for producers developing natural gas supplies in the Rocky Mountain region."

WIC has begun the pre-filing process with the Federal Energy Regulatory Commission (FERC) for the proposed Piceance Expansion. The pre-filing process will allow WIC to work with the FERC to address environmental issues, conduct community outreach initiatives, and consult with other permitting agencies before the company formally submits its complete application for the expansion. The pre-filing process will also enable the FERC to expedite its review of WIC's formal application, which WIC plans to file in October 2004. Pending FERC approval, the company plans to begin construction in September 2005 to have the pipeline in service in December 2005.

Interested parties may obtain more information by contacting Craig Coombs (719) 520-4387, Laine Lobban (719) 520-4344, or Roland Harris (719) 520-4380.

El Paso Corporation provides natural gas and related energy products in a safe, efficient, dependable manner. The company owns North America's largest natural gas pipeline system and one of North America's largest independent natural gas producers. For more information, visit www.elpaso.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, including, without limitation, the ability to implement and achieve our objectives in the long-range plan; the level of interest in the proposed Piceance Basin lateral expansion project and receipt of any necessary governmental approvals therefore; and other factors described in the company's (and its affiliates') Securities and Exchange Commission filings. While the company makes these statements and projections in good faith, neither the company nor its management can guarantee that anticipated future results will be achieved. Reference must be made to those filings for additional important factors that may affect actual results. The company assumes no obligation to publicly update or revise any forward-looking statements made herein or any other forward-looking statements made by the company, whether as a result of new information, future events, or otherwise.