Filed by Pacific Energy Partners, L.P. Pursuant to Rule 425 under the Securities Act of 1933 and deemed filed pursuant to Rule 14a-12 under the Securities and Exchange Act of 1934 Subject Company: Pacific Energy Partners, L.P. Commission File No. 1-31345 Pacific Energy Partners, L.P. Announces Record Date for Special Meeting of Unitholders LONG BEACH, Calif.--(BUSINESS WIRE)--Sept. 8, 2006--Pacific Energy Partners, L.P. (NYSE:PPX) ("Pacific Energy" or the "Partnership") announced that it has set the close of business on September 18, 2006, as the record date for determining the unitholders entitled to receive notice of, and to vote at, the special meeting to be held to consider the proposed merger transaction with Plains All American Pipeline, L.P. ("Plains"). The time, date and location of the unitholder meeting will be announced at a later date. In addition to the approval of the unitholders of Plains and Pacific Energy, the completion of the transaction remains subject to approvals of certain state utility commissions and other regulatory bodies. Pacific Energy anticipates closing the transaction in the fourth quarter of 2006. About Pacific Energy: Pacific Energy Partners, L.P. is a master limited partnership headquartered in Long Beach, California. Pacific Energy is engaged principally in the business of gathering, transporting, storing and distributing crude oil, refined products and other related products. Pacific Energy generates revenues by transporting such commodities on its pipelines, by leasing capacity in its storage facilities and by providing other terminaling services. Pacific Energy also buys and sells crude oil, activities that are generally complementary to its crude oil operations. Pacific Energy conducts its business through two business units, the West Coast Business Unit, which includes activities in California and the Philadelphia, PA, area, and the Rocky Mountain Business Unit, which includes activities in five Rocky Mountain states and Alberta, Canada. For additional information about the partnership, please visit www.PacificEnergy.com. Investor Notice: Pacific Energy and Plains have filed a joint proxy statement/prospectus and other documents with the Securities and Exchange Commission ("SEC") with respect to the proposed merger of Pacific Energy with and into Plains. Upon being declared effective by the SEC, a definitive joint proxy statement/prospectus will be sent to security holders of Pacific Energy and Plains seeking their approval of the merger and related transactions. Investors and security holders are urged to carefully read the joint proxy statement/prospectus because it contains important information, including detailed risk factors, regarding Pacific Energy, Plains and the merger. Investors and security holders may obtain a free copy of the definitive joint proxy statement/prospectus, when it becomes available, and other documents containing information about Pacific Energy and Plains, without charge, at the SEC's web site at www.sec.gov. Copies of the definitive joint proxy statement/prospectus, when it becomes available, and the SEC filings that are incorporated by reference in the joint proxy statement/prospectus may also be obtained free of charge by directing a request to Pacific Energy or Plains. Pacific Energy or Plains and the officers and directors of the respective general partners of Pacific Energy or Plains may be deemed to be participants in the solicitation of proxies from their security holders in connection with the proposed transaction. Information about these persons can be found in Pacific Energy's or Plains' respective Annual Reports on Form 10-K filed with the SEC, and additional information about such persons may be obtained from the joint proxy statement/prospectus. CONTACT: Pacific Energy Partners, L.P. Jennifer Shigei, 562-728-2871 (Investor Relations) fax: 562-728-2881 JShigei@PacificEnergy.com