Exhibit 10.10

Execution Copy

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OMNIBUS AGREEMENT        AMONG        THE ANSCHUTZ CORPORATION        PACIFIC ENERGY GP, INC.        PACIFIC ENERGY GROUP LLC        AND        PACIFIC
ENERGY PARTNERS, L.P.

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OMNIBUS AGREEMENT

THIS OMNIBUS AGREEMENT is entered into on, and effective as of, the Closing Date, among The Anschutz Corporation, a Kansas corporation ("Anschutz"), Pacific
Energy GP, Inc., a Delaware corporation (including any permitted successors and assigns under the MLP Agreement (as defined herein), the "General Partner"), for itself and on behalf of the MLP
in its capacity as general partner, Pacific Energy Group LLC, a Delaware limited liability company (the "OLLC"), and Pacific Energy Partners, L.P., a Delaware limited partnership (the "MLP").

R E C I T A L S:

Anschutz, the MLP, the OLLC and the General Partner desire by their execution of this Agreement to evidence their understanding, (i) as more fully set
forth in Article II of this Agreement, with respect to (a) those business opportunities that the Anschutz Entities will not pursue during the term of this Agreement unless the MLP has
declined to engage in such business opportunity for its own account and (b) the procedures whereby such business opportunities are to be offered to the MLP and accepted or declined, and
(ii) as more fully set forth in Article III of this Agreement, with respect to certain indemnification obligations of Anschutz in favor of the Partnership Group.

In
consideration of the premises and the covenants, conditions, and agreements contained herein, and for other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto hereby agree as follows:

ARTICLE I  Definitions



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ARTICLE II  Business Opportunities



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Restricted Business shall not include any activities performed by an Anschutz Entity primarily in connection with oil and gas properties owned jointly by an Anschutz Entity with other
Persons, whether such activities are performed as the operator pursuant to an operating agreement or otherwise. In

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addition, notwithstanding anything to the contrary herein, nothing in this Article II shall in any way restrict or impair:



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ARTICLE III  Indemnification



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ARTICLE IV  Wahsatch Operations



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ARTICLE V  Miscellaneous



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[SIGNATURE
PAGE FOLLOWS]

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IN
WITNESS WHEREOF, the Parties have executed this Agreement on, and effective as of, the Closing Date.

| | THE ANSCHUTZ CORPORATION                                                                                                 
| | -------------------------------------------------------------------------------------------------------------------------
| | By:                                                                                                                      
| |                                                                                                                          
| | Address for Notice:                                                                                                      
| | 555 17th Street
Suite 2400
Denver, Colorado 80110
Phone: (303) 298-1000
Fax: (303) 299-1425
Attention: Mr. Lynn Wood     
| | PACIFIC ENERGY GP, INC.                                                                                                  
| | By:                                                                                                                      
| | Address for Notice:                                                                                                      
| | 5900 Cherry Avenue
Long Beach, California 90805
Phone: (562) 728-2810
Fax: (562) 728-2823
Attention: Mr. Irvin Toole, Jr.

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| | PACIFIC ENERGY GROUP LLC                                                                                                 
| | -------------------------------------------------------------------------------------------------------------------------
| | By:                                                                                                                      
| |                                                                                                                          
| |                                                                                                                          
| |                                                                                                                          
| | Address for Notice:                                                                                                      
| | 5900 Cherry Avenue
Long Beach, California 90805
Phone: (562) 728-2810
Fax: (562) 728-2823
Attention: Mr. Irvin Toole, Jr.
| | PACIFIC ENERGY PARTNERS, L.P.                                                                                            
| | By:                                                                                                                      
| |                                                                                                                          
| |                                                                                                                          
| | Address for Notice:                                                                                                      
| | 5900 Cherry Avenue
Long Beach, California 90805
Phone: (562) 728-2810
Fax: (562) 728-2823
Attention: Mr. Irvin Toole, Jr.

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