SEC Form 3

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 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* INFRASTRUX HOLDINGS, LLC (Last) (First) (Middle) C/O TENASKA CAPITAL MANAGEMENT, LLC 1044 N. 115TH STREET, SUITE 400 (Street) OMAHA NE 68154-4446 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 07/01/2010	3. Issuer Name and Ticker or Trading Symbol WILLBROS GROUP INC [ WG ]
		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 of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

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	7,919,576(1)	D(2)

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: 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

1. Name and Address of Reporting Person* INFRASTRUX HOLDINGS, LLC (Last) (First) (Middle) C/O TENASKA CAPITAL MANAGEMENT, LLC 1044 N. 115TH STREET, SUITE 400 (Street) OMAHA NE 68154-4446 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* TPF POWER, INC. (Last) (First) (Middle) C/O TENASKA CAPITAL MANGEMENT, LLC 1044 N. 115TH STREET, SUITE 400 (Street) OMAHA NE 68154-4446 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* TPF INFRASTRUX HOLDINGS, LLC (Last) (First) (Middle) C/O TENASKA CAPITAL MANAGEMENT, LLC 1044 N. 115TH STREET, SUITE 400 (Street) OMAHA NE 68154-4446 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* TENASKA POWER FUND, LP (Last) (First) (Middle) C/O TENASKA CAPITAL MANAGEMENT, LLC 1044 N. 115TH STREET, SUITE 400 (Street) OMAHA NE 68154-4446 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* TENASKA PF G, LLC (Last) (First) (Middle) C/O TENASKA CAPITAL MANAGEMENT, LLC 1044 N. 115TH STREET, SUITE 400 (Street) OMAHA NE 68154-4446 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* TENASKA PF, INC. (Last) (First) (Middle) C/O TENASKA CAPITAL MANAGEMENT, LLC 1044 N. 115TH STREET, SUITE 400 (Street) OMAHA NE 68154-4446 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. The reporting person acquired these securities on July 1, 2010, as part of the consideration for the reporting person's common stock of InfrastruX Group, Inc. ("IFX"), which the Issuer acquired by merger on July 1, 2010 pursuant to the Agreement and Plan of Merger, dated as of March 11, 2010, by and among the Issuer, Co Merger Sub I, Inc., Ho Merger Sub II, LLC and IFX (as amended, the "Merger Agreement"). The Merger Agreement provides that the former shareholders of IFX may in the future receive shares of preferred stock of the Issuer under certain circumstances related to, among other things, the financial performance of IFX during the 2010 and 2011 calendar years. The reporting person's right to potentially receive additional shares pursuant to this earn-out right became fixed and irrevocable on July 1, 2010, the effective date of the merger.

2. These shares are indirectly owned by TPF Power, Inc., the manager of InfrastruX Holdings, LLC, TPF InfrastruX Holdings, LLC, the majority owner of InfrastruX Holdings, LLC, Tenaska Power Fund, L.P., the sole owner of TPF InfrastruX Holdings, LLC, Tenaska PF G, LLC, the general partner of Tenaska Power Fund, L.P., and Tenaska PF, Inc., the manager of Tenaska PF G, LLC. These entities may be deemed indirect beneficial owners of the reported securities.

	/s/ Ryan T. Schroer, Vice President of TPF Power, Inc., Manager of INFRASTRUX HOLDINGS, LLC	07/12/2010
	/s/ Ryan T. Schroer, Vice President of TPF POWER, INC.	07/12/2010
	/s/ Ryan T. Schroer, Vice President of TPF Power, Inc., Manager of TPF INFRASTRUX HOLDINGS, LLC	07/12/2010
	/s/ Ryan T. Schroer, Vice President of Tenaska PF, Inc., Manager of Tenaska PF G, LLC, General Partner of TENASKA POWER FUND, L.P.	07/12/2010
	/s/ Ryan T. Schroer, Vice President of Tenaska PF, Inc., Manager of TENASKA PF G, LLC	07/12/2010
	/s/ Ryan T. Schroer, Vice President of TENASKA PF, INC.	07/12/2010
	** Signature of Reporting Person	Date
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