Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  ANADARKO PETROLEUM CORP
 2. Date of Event Requiring Statement (Month/Day/Year)
06/22/2006		 3. Issuer Name and Ticker or Trading Symbol
WESTERN GAS RESOURCES INC [WGR]
(Last)
(First)
(Middle)
1201 LAKE ROBBINS DR.		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
06/29/2006
(Street)

THE WOODLANDS, TX 77380		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 0 (1)
I (1)
See Footnote (1 & 2) (2)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
ANADARKO PETROLEUM CORP
1201 LAKE ROBBINS DR.
THE WOODLANDS, TX 77380		     X    

Signatures

/s/Charlene A. Ripley, Vice President, General Counsel, Corporate Secretary and Chief Compliance Officer 07/05/2006
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) This Form 3 is being filed as a result of certain Voting Agreements covering 13,900,602 shares (the "Shares") of common stock of Western Gas Resources, Inc. ("Western Gas") entered into on June 22, 2006 between Anadarko Petroleum Corporation ("Anadarko") and each of Dean Phillips, Bill M. Sanderson and Mabeth Sanderson, Cedar Assets Trust, James A. Senty, Roswitha Stonehocker, Walter L. Stonehocker, Brion Wise, John F. Chandler, and Peter A. Dea as part of a proposed acquisition of Western Gas by Anadarko. The Shares include 749,464 shares that are issuable upon the exercise of outstanding stock options that are exercisable within 60 days of the date of the Voting Agreements.
(2) For additional information regarding the Voting Agreements and the acquisition of Western Gas by Anadarko, see the Schedule 13D filed by Anadarko with the Securities and Exchange Commission on June 29, 2006. Anadarko expressly disclaims any beneficial ownership of the Shares. Anadarko has no "pecuniary interest" in the Shares.

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