EX-3.4

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Exhibit 3.4

AMENDMENT NO. 2 TO
FIRST AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP
OF
PACIFIC ENERGY PARTNERS, L.P.

        This Amendment No. 2 (this " Amendment No. 2 ") to the First Amended and Restated Agreement of Limited Partnership of Pacific Energy Partners, L.P. (the " Partnership "), as amended by Amendment No. 1, effective as of August 1, 2003 (the " Partnership Agreement "), is entered into effective as of January 27, 2004, by Pacific Energy GP, Inc., a Delaware corporation, as general partner of the Partnership (the " General Partner "). Capitalized terms used but not defined herein are used as defined in the Partnership Agreement.

         WHEREAS , the General Partner, the Organizational Limited Partner and the Limited Partners of the Partnership entered into that certain First Amended and Restated Agreement of Limited Partnership of the Partnership dated as of July 26, 2002;

         WHEREAS , the General Partner adopted Amendment No. 1 to the First Amended and Restated Agreement of Limited Partnership of the Partnership effective as of August 1, 2003;

         WHEREAS , Section 13.1(d)(i) of the Partnership Agreement provides that the General Partner may amend any provision of the Partnership Agreement without the approval of any Partner or Assignee to reflect a change that, in the discretion of the General Partner, does not adversely affect the Limited Partners (including any particular class of Partnership Interests) in any material respect;

         WHEREAS , acting pursuant to the power and authority granted to it under Section 13.1(d)(i) of the Partnership Agreement, the General Partner has determined that the following amendment to the Partnership Agreement does not adversely affect the Limited Partners (including any particular class of Partnership Interests as compared to other classes of Partnership Interests) in any material respect.

         NOW THEREFORE , the General Partner does hereby amend the Partnership Agreement as follows:

        Section 1. Amendment .

        Section 5.7(b) is hereby amended and restated as follows:

        (b)   During the Subordination Period, the Partnership may also issue an unlimited number of Parity Units without the prior approval of the Unitholders, if such issuance occurs (i) in connection with an Acquisition or a Capital Improvement or (ii) within 850 days of completion of an Acquisition or Commencement of Commercial Service of a Capital Improvement, and the net proceeds from such issuance are used to repay debt incurred in connection with, an Acquisition or a Capital Improvement, in each case where such Acquisition or Capital Improvement involves assets that, if acquired (or in the case of a Capital Improvement, Commenced Commercial Service) by the Partnership as of the date that is one year prior to the first day of the Quarter in which the Partnership completed such Acquisition or such Capital Improvement Commenced Commercial Service ("One Year Test Period"), would have resulted, on a pro forma or estimated pro forma basis, as applicable, in an increase in:

        (A)  the amount of Adjusted Operating Surplus generated by the Partnership on a per-Unit basis (for all Outstanding Units) with respect to the One Year Test Period, on a pro forma or estimated pro forma basis, as applicable, as compared to

        (B)  the actual amount of Adjusted Operating Surplus generated by the Partnership on a per-Unit basis (for all Outstanding Units) with respect to the One Year Test Period.

The preceding calculation is referred to in this Section 5.7(b) as the " Accretion Test ." The amount of Adjusted Operating Surplus in clause (A) of the Accretion Test shall be calculated on a pro forma or estimated pro forma basis, as applicable, as described below. The General Partner's good faith determination that such an increase would have resulted from such Acquisition or Capital Improvement shall be conclusive.

The following shall apply with respect to the foregoing provisions of Sec