Exhibit 10.3

SECOND AMENDMENT TO CREDIT AGREEMENT

THIS SECOND AMENDMENT TO CREDIT AGREEMENT (herein called the "Second Amendment") made as of the 12th day of December, 2003, by and among PACIFIC ENERGY GROUP LLC
("Borrower"), a Delaware limited liability company, PACIFIC ENERGY PARTNERS, L.P. ("Pacific Energy Partners"), a Delaware limited partnership, and FLEET NATIONAL BANK, as administrative agent (in such
capacity, "Administrative Agent"), and the Lenders referred to below.

W
I T N E S S E T H:

WHEREAS,
Borrower, Pacific Energy Partners, Administrative Agent, Syndication Agent, Co-Documentation Agents, Arrangers and the lenders party thereto ("Lenders") have entered
into that certain Credit Agreement dated as of July 19, 2002, as amended by a First Amendment to Credit Agreement dated July 18, 2003 (as so amended, the "Original Agreement") for the
purpose and consideration therein expressed, whereby Lenders became obligated to make loans to Borrower as therein provided; and

WHEREAS,
Borrower, Pacific Energy Partners, Administrative Agent, and Lenders party hereto desire to amend the Original Agreement for the purposes expressed herein;

NOW,
THEREFORE, in consideration of the premises and the mutual covenants and agreements contained herein and in the Original Agreement and in consideration of the loans and other credit
that may hereafter be extended by Lenders to Borrower, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto do hereby agree
as follows:

ARTICLE
I.Definitions and References

Section 1.1.Terms Defined in the Original Agreement. Unless the context otherwise requires or unless otherwise expressly defined
herein, the terms defined in the Original Agreement shall have the same meanings whenever used in this Second Amendment.

ARTICLE
II.Amendments to Original Agreement

Section 2.1. Definitions. The definitions of "Applicable Rating Level", "Base Rate Margin", "Commitment Fee Rate", "Letter of
Credit Rate" and "LIBOR Rate Margin" set forth in Section 1.1 of the Original Agreement are hereby amended in their entirety to read as follows:



Applicable
Rating Level

S&P

Moody'sLevel I

3BB+

3Baa1Level II

BBB

Baa2Level III

BBB-

Baa3Level IV

BB+

Ba1Level V

BB

Ba2Level VI

£BB-

£Ba3




If
either of the Rating Agencies shall not have in effect a Borrower Debt Rating or if the rating system of either of the Rating Agencies shall change, or if either of the Rating
Agencies shall cease to be in the business of rating corporate debt obligations, Borrower and Majority Lenders shall negotiate in good faith to amend this definition to reflect such changed rating
system or the unavailability of ratings from such Rating Agency, but until such an agreement shall be reached, the Applicable Rating Level shall be based only upon the Borrower Debt Rating by the
remaining Rating Agency.

"Base Rate Margin" means, on any date, the percent per annum set forth below based on the Applicable Rating Level in effect on such date:

Base Rate MarginApplicable Rating Level

Revolver Loans

Term LoansLevel I

0.00
%
0.00
%Level II

0.00
%
0.00
%Level III

0.00
%
0.00
%Level IV

0.00
%
0.25
%Level V

0.00
%
0.25
%Level VI

0.00
%
0.25
%


Changes
in the applicable Base Rate Margin will occur automatically, without prior notice as changes in the Applicable Rating Level occur. Administrative Agent will give notice promptly
to Borrower and Lenders of changes in the applicable Base Rate Margin.

"Commitment Fee Rate" means, on any date, the rate per annum set forth below based on the Applicable Rating Level on such date:

Applicable Rating Level

Commitment Fee RateLevel I

.125
%Level II

.1875
%Level III

.20
%Level IV

.25
%Level V

.30
%Level VI

.375
%


Changes
in the applicable Commitment Fee Rate will occur automatically, without prior notice as changes in the Applicable Rating Level occur. Administrative Agent will give notice
promptly to Borrower and Lenders of changes in the Commitment Fee Rate.

"Letter of Credit Fee Rate" means, on any day, the rate per annum set forth below based on the Applicable Rating Level on such date:

Applicable Rating Level

Letter of Credit
Fee RateLevel I

0.75
%Level II

0.875
%Level III

1.125
%Level IV

1.375
%Level V

1.75
%Level VI

2.00
%


Changes
in the applicable Letter of Credit Fee Rate will occur automatically, without prior notice as changes in the Applicable Rating Level occur. Administrative Agent will give notice
promptly to Borrower and Revolver Lenders of changes in the Letter of Credit Fee Rate.

"LIBOR Rate Margin" means, on any date, the percent per annum set forth below based on the Applicable Rating Level in effect on such date:

LIBOR Rate MarginApplicable Rating Level

Revolver Loans

Term LoansLevel I

0.75
%
2.00
%Level II

0.875
%
2.00
%Level III

1.125
%
2.00
%Level IV

1.375
%
2.25
%Level V

1.75
%
2.25
%Level VI

2.00
%
2.25
%


Changes
in the applicable LIBOR Rate Margin will occur automatically, without prior notice as changes in the Applicable Rating Level occur. Administrative Agent will give notice promptly
to Borrower and Lenders of changes in the applicable LIBOR Rate Margin.

Section 2.2.Acquisition Period. Section 1.1 of the Original Agreement is hereby amended by adding the definition of
"Acquisition Period" immediately prior to the definition of "Administrative Agent", to read as follows:



Section 2.3.Increase in Interest Rates and Fees During an Acquisition Period. Section 2.12 of the Original Agreement is
hereby amended by adding the following Section 2.12(e):



Section 2.4.Leverage Ratio. The first sentence of Section 7.10 of the Original Agreement is hereby amended in its entirety
to read as follows:



ARTICLE
III.Conditions of Effectiveness

Section 3.1.Effective Date.



ARTICLE
IV.Representations and Warranties

Section 4.1.Representations and Warranties of Borrower. In order to induce Administrative Agent and Majority Lenders, all Revolver
Lenders and all Term Lenders, as the case may be, to enter into this Second Amendment, Borrower represents and warrants to each Lender that:



ARTICLE
V.Miscellaneous

Section 5.1. Ratification of Agreements. The Original Agreement as hereby amended is hereby ratified and confirmed in all respects.
Any reference to the Credit Agreement in any Loan Document shall be deemed to be a reference to the Original Agreement as hereby amended. The execution, delivery and effectiveness of this Second
Amendment shall not, except as expressly provided herein, operate as a waiver of any right, power or remedy of Lenders or Administrative Agent under the Credit Agreement,
the Notes, or any other Loan Document nor constitute a waiver of any provision of the Credit Agreement, the Notes or any other Loan Document.

Section 5.2. Survival of Agreements. All representations, warranties, covenants and agreements of Borrower herein shall survive the
execution and delivery of this Second Amendment and the performance hereof, and shall further survive until all of the Obligations are paid in full. All statements and agreements contained in any
certificate or instrument delivered by any Restricted Person hereunder or under the Credit Agreement to Administrative Agent or any Lender shall be deemed to constitute representations and warranties
by, and agreements and covenants of, Borrower under this Second Amendment and under the Credit Agreement.

Section 5.3. Loan Documents. This Second Amendment is a Loan Document, and all provisions in the Credit Agreement pertaining to
Loan Documents apply hereto.

Section 5.4.Governing Law. This Second Amendment shall be governed by and construed in accordance with the laws applicable to the
Credit Agreement.

Section 5.5.Counterparts. This Second Amendment may be separately executed in counterparts and by the different parties hereto in
separate counterparts, each of which when so executed shall be deemed to constitute one and the same Second Amendment.

THIS SECOND AMENDMENT AND THE OTHER LOAN DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS OF THE PARTIES.

[REMAINDER
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IN
WITNESS WHEREOF, this Agreement is executed as of the date first written above.

|BORROWER: |  | PACIFIC ENERGY GROUP LLC
|--------- |  | ------------------------
|          |  | By:                     

|PACIFIC ENERGY PARTNERS: |  | PACIFIC ENERGY PARTNERS, L.P.:
|------------------------ |  | ------------------------------
|                         |  | By:                           
|                         |  |                               

| |  | FLEET NATIONAL BANK,
Administrative Agent, LC Issuer and a Lender
| |  | -----------------------------------------------------------------
| |  | By:                                                              
| |  | FLEET SECURITIES, INC.,
Co-Lead Arranger and Co-Book Manager     
| |  | By:                                                              



Signature Page to Second Amendment
To Credit Agreement

In
Witness Whereof, the undersigned Lender hereby enters into the Second Amendment to Credit Agreement dated as of December 12th, 2003 among Pacific Energy Group LLC, Pacific
Energy Partners, L.P., Fleet National Bank, as administrative agent, and the Lender's signatory thereto.

| |  | Name of Lender
| |  | --------------
| |  | By:           



CONSENT AND AGREEMENT

The undersigned each hereby consents to the provisions of this Second Amendment and the transactions contemplated herein and hereby ratifies and confirms the
Guaranty dated as of July 19, 2002, made by it favor of FLEET NATIONAL BANK, as administrative agent, and agree that its obligations and covenants thereunder are unimpaired hereby and shall
remain in full force and effect.

| |  | PACIFIC MARKETING & TRANSPORTATION LLC
ROCKY MOUNTAIN PIPELINE SYSTEM LLC
ANSCHUTZ RANCH EAST PIPELINE LLC
RANCH PIPELINE LLC
| |  | -----------------------------------------------------------------------------------------------------------------------------
| |  | By:                                                                                                                          

CONSENT AND AGREEMENT

The undersigned hereby consents to the provisions of this Second Amendment and the transactions contemplated herein and hereby ratifies and confirms the Guaranty
dated as of July 19, 2002, made by it in favor of FLEET NATIONAL BANK, as administrative agent (in such capacity), and agrees that its obligations and covenants thereunder are unimpaired hereby
and shall remain in full force and effect.

| |  | PACIFIC ENERGY PARTNERS, L.P.
| |  | -----------------------------
| |  | By:                          
| |  |                              



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