press release

Plains All American Pipeline acquires Cal Ven Pipeline from Unocal Canada

The following news release was issued by Plains All-American Pipeline, LP

Houston, May 7, 2004 - Plains All American Pipeline, L.P. (NYSE: PAA) announced today that its subsidiary Plains Marketing Canada, L.P. has acquired the Cal Ven Pipeline System from Cal Ven Limited, a subsidiary of Unocal Canada Limited, which is a subsidiary of Unocal Corporation (NYSE: UCL). The total purchase price was approximately US$19 million (approximately $26.2 million Canadian), including transaction costs. The transaction was funded through a combination of cash on hand and borrowings under the Partnership's revolving credit facilities. The effective date for the transaction was January 1, 2004.

The Cal Ven Pipeline System is comprised of approximately 195 miles of 8-inch and 10-inch gathering and mainline crude oil pipelines. The system is located in northern Alberta and delivers crude oil into the Rainbow Pipeline System at Utikuma. The Rainbow Pipeline System then transports the crude south to the Edmonton market, where it can be used in local refineries or shipped on connecting pipelines to the U.S. market.

Except for the historical information contained herein, the matters discussed in this news release are forward-looking statements that involve certain risks and uncertainties. These risks and uncertainties include, among other things, successful integration and future performance of assets acquired, refinery downtime, demand for various grades of crude oil and resulting changes in pricing conditions or transmission throughput requirements, successful third party drilling efforts, availability of third party production volumes for transportation and marketing, political and economic stability of foreign sources of crude oil, continued creditworthiness of, and performance by, our counterparties, the effects of competition, the success of our risk management activities, the effect of changes in the value of the Canadian dollar, regulatory changes, weather interference, and other factors and uncertainties inherent in the marketing, transportation, terminaling, gathering and storage of crude oil discussed in the Partnership's filings with the Securities and Exchange Commission.

Plains All American Pipeline, L.P. is engaged in interstate and intrastate crude oil transportation, and crude oil gathering, marketing, terminaling and storage, as well as the marketing and storage of liquefied petroleum gas and other petroleum products, primarily in Texas, California, Oklahoma, Louisiana and the Canadian Provinces of Alberta and Saskatchewan. The Partnership's common units are traded on the New York Stock Exchange under the symbol "PAA." The Partnership is headquartered in Houston, Texas.

Updated: May 2004