Exhibit 99.1
Pacific Energy Partners, L.P. Announces Signing of Definitive Purchase
Agreement to Acquire Mid Alberta Pipeline

    LONG BEACH, Calif.--(BUSINESS WIRE)--June 2, 2004--Pacific Energy
Partners, L.P. (NYSE:PPX) ("the Partnership") announced today that a
wholly-owned subsidiary has entered into a definitive asset purchase
agreement to acquire the Mid Alberta Pipeline ("MAPL Pipeline"),
located in Alberta, Canada, from Imperial Oil. The 138-mile MAPL
Pipeline is a proprietary pipeline with a throughput capacity of
approximately 50,000 barrels per day if transporting light crude oil.
The MAPL Pipeline originates at Edmonton, Alberta and terminates at
Sundre, Alberta, where it connects to the Rangeland system. The
Partnership acquired the Rangeland system on May 11, 2004.
    The acquisition price for the MAPL Pipeline assets is Cdn$31.5
million, Cdn$5 million of which is deferred for three years. In
addition, we anticipate spending an estimated Cdn$8 million for
linefill, transaction costs and first-year transition capital
expenditures. At an exchange rate of US$1 = Cdn$1.3685, as of June 1,
2004, the all-in acquisition cost will be approximately US$29 million.
This transaction is expected to close in late June, 2004, following
receipt of regulatory approvals and fulfillment of other customary
closing conditions. Funding of the purchase will be from the
Partnership's new Canadian revolving credit facility.
    Irv Toole, President and Chief Executive Officer, said, "The
acquisitions of Rangeland and MAPL are a continuation of our regional
development plans in the Rocky Mountains. They provide a unique and
strategic opportunity for Pacific Energy Partners to participate in
the expected increase in production of synthetic crude from the
Alberta oil sands by providing to Canadian producers and U.S. Rocky
Mountain refiners an integrated pipeline delivery system from
Edmonton, Alberta to U.S. PADD IV markets. These acquisitions are
expected to have significant synergies with the Partnership's U.S.
pipeline systems and will enable us to provide expanded services to
our Rocky Mountain customers."
    Mr. Toole continued, "The combined acquisitions are expected to be
slightly accretive in the initial year of operation, the period during
which additional pipeline facilities are to be constructed by the
Partnership in Edmonton. Once the integration of these facilities is
complete, in about a year, we expect the acquisitions to be
approximately five percent accretive to net income and cash
distributions to unitholders."
    Pacific Energy Partners, L.P. is a Delaware limited partnership
headquartered in Long Beach, California. Pacific Energy Partners, L.P.
is engaged principally in the business of gathering, transporting,
storing and distributing crude oil and other related products in
California and the Rocky Mountain region. Pacific Energy Partners,
L.P. generates revenue primarily by transporting crude oil on its
pipelines and by leasing capacity in its storage facilities. Pacific
Energy Partners, L.P. also buys, blends and sells crude oil,
activities that are complementary to its pipeline transportation
business.

    This news release may include "forward-looking" statements within
the meaning of Section 27A of the Securities Act of 1933, as amended,
and Section 21E of the Securities Exchange Act of 1934, as amended.
All statements other than statements of historical fact included or
incorporated herein may constitute forward-looking statements.
Although the Partnership believes that the forward-looking statements
are reasonable, it can give no assurance that such expectations will
prove to be correct. The forward-looking statements involve risks and
uncertainties that affect the Partnership's operations and financial
performance. Among the factors that could cause results to differ
materially are those risks discussed in the Partnership's filings with
the Securities and Exchange Commission, including our Annual Report on
Form 10-K for the year ended December 31, 2003.

    CONTACT: Pacific Energy Partners, L.P.
             Thomas L. Lambert, 562-728-2871 (Investor Relations)
             562-728-2881 (fax)