EX-4.2






Exhibit 4.2




FOURTH SUPPLEMENTAL INDENTURE FOR




ADDITIONAL SUBSIDIARY GUARANTEES




Fourth Supplemental Indenture (this “Supplemental Indenture for Additional
Guarantees”), dated as of March 14, 2006, among the guaranteeing subsidiaries listed on
Schedule A hereto (the “Guaranteeing Subsidiaries”), each an indirect subsidiary of NRG
Energy, Inc., a Delaware corporation (the “Company”), the Company, the other Guarantors (as defined
in the Indenture referred to herein) and Law Debenture Trust Company of New York, as trustee under
the indentures referred to below (the “Trustee”).



W I T N E S S E T H




WHEREAS, the Company has heretofore executed and delivered to the Trustee an indenture (the
“Base Indenture”), dated as of February 2, 2006, between the Company and the Trustee, as amended by
a second supplemental indenture (the “Second Supplemental Indenture” and, together with the Base
Indenture, the “Indenture”), dated as of February 2, 2006, among the Company, the Guarantors named
therein and the Trustee, providing for the original issuance of an aggregate principal amount of
$2,400 million of 7.375% Senior Notes due 2016 (the “Initial Notes”), and, subject to the terms of
the Indenture, future unlimited issuances of 7.375% Senior Notes due 2016 (the “Additional Notes,”
and together with the Initial Notes, the “Notes”);



WHEREAS, the Indenture provides that under certain circumstances the Guaranteeing Subsidiaries
shall execute and deliver to the Trustee a supplemental indenture pursuant to which the
Guaranteeing Subsidiaries shall unconditionally guarantee all of the Company’s Obligations under
the Notes and the Indenture (the “Additional Guarantees”); and



WHEREAS, pursuant to Section 4.17 of the Second Supplemental Indenture, the Trustee, the
Company and the other Guarantors are authorized and required to execute and deliver this
Supplemental Indenture for Additional Guarantees.



NOW THEREFORE, in consideration of the foregoing and for good and valuable consideration, the
receipt of which is hereby acknowledged, the Guaranteeing Subsidiaries, the Trustee, the Company
and the other Guarantors mutually covenant and agree for the equal and ratable benefit of the
Holders of the Notes as follows:



1. Capitalized Terms. Unless otherwise defined in this Supplemental Indenture for Additional
Guarantees, capitalized terms used herein without definition shall have the meanings assigned to
them in the Indenture.



2. Agreement to be Bound; Guarantee. Each of the Guaranteeing Subsidiaries hereby becomes a
party to the Second Supplemental Indenture as a Guarantor and as such will have all of the rights
and be subject to all of the Obligations and agreements of a Guarantor under the Indenture. Each
of the Guaranteeing Subsidiaries hereby agrees to be bound by all of the provisions of the Second
Supplemental Indenture applicable to a Guarantor and to perform all of the Obligations and
agreements of a Guarantor under the Second Supplemental Indenture. In furtherance of the
foregoing, each of the Guaranteeing Subsidiaries shall be deemed a Guarantor for purposes of
Article 10 of the Second Supplemental Indenture, including, without limitation, Section 10.02
thereof.



3. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED
TO CONSTRUE THIS SUPPLEMENTAL INDENTURE FOR ADDITIONAL GUARANTEES BUT WITHOUT GIVING EFFECT TO
APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER
JURISDICTION WOULD BE REQUIRED THEREBY.



4. Counterparts. The parties may sign any number of copies of this Supplemental Indenture for
Additional Guarantees. Each signed copy shall be an original, but all of them together represent
the same agreement.



5. Effect of Headings. The Section headings herein are for convenience only and shall not
affect the construction hereof.



6. The Trustee. The Trustee shall not be responsible in any manner whatsoever for or in
respect of the validity or sufficiency of this Supplemental Indenture for Additional Guarantees or
for or in respect of the recitals contained herein, all of which recitals are made solely by the
Guaranteeing Subsidiaries and the Company.



7. Ratification of Indenture; Supplemental Indenture for Additional Guarantees Part of
Indenture. Except as expressly amended hereby, the Indenture is in all respects ratified and
confirmed and all the terms, conditions and provisions thereof shall remain in full force and
effect. This Supplemental Indenture for Additional Guarantees shall form a part of the Indenture
for all purposes, and every Holder of Notes heretofore or hereafter authenticated and delivered
shall by bound hereby.



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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture for
Additional Guarantees to be duly executed and attested, all as of the date first above written.




Guaranteeing Subsidiaries:




NRG BLOCKER I LP


NRG BLOCKER II LP


NRG BLOCKER III INC.


NRG BLOCKER IV INC.


NRG BLOCKER V INC.


NRG BLOCKER VI INC.


NRG BLOCKER VII INC.


TEXAS GENCO LLC


TEXAS GENCO FINANCING CORP.


TEXAS GENCO GP, LLC


NEW GENCO GP, LLC


TEXAS GENCO OPERATING SERVICES LLC


TEXAS GENCO HOLDINGS, INC.




By:  /s/ George P. Schaefer

Name: George P. Schaefer

Title: Vice President





GCP FUNDING COMPANY, LLC






NEW GENCO LP, LLC


TEXAS GENCO LP, LLC




By:  /s/ Susan T. Dubb

Name: Susan T. Dubb

Title: Treasurer and Secretary





TEXAS GENCO II, LP


TEXAS GENCO SERVICES, LP




By: New Genco GP, LLC, its General Partner




By:  /s/ George P. Schaefer

Name: George P. Schaefer

Title: Vice President and Assistant Treasurer





TEXAS GENCO, LP




By: Texas Genco GP, LLC, its General Partner




By:  /s/ George P. Schaefer

Name: George P. Schaefer

Title: Vice President and Assistant Treasurer





Issuer:




NRG ENERGY, INC.




By:  /s/ George P. Schaefer

Name: George P. Schaefer

Title: Vice President and Treasurer





Existing Guarantors:




ARTHUR KILL POWER LLC






ASTORIA GAS TURBINE POWER LLC


BERRIANS I GAS TURBINE POWER LLC


BIG CAJUN II UNIT 4 LLC


CAPISTRANO COGENERATION COMPANY


CHICKAHOMINY RIVER ENERGY CORP.


COMMONWEALTH ATLANTIC POWER LLC


CONEMAUGH POWER LLC


CONNECTICUT JET POWER LLC


DEVON POWER LLC


DUNKIRK POWER LLC


EASTERN SIERRA ENERGY COMPANY


HANOVER ENERGY COMPANY


HUNTLEY POWER LLC


INDIAN RIVER OPERATIONS INC.


INDIAN RIVER POWER LLC


JAMES RIVER POWER LLC


KAUFMAN COGEN LP


KEYSTONE POWER LLC


LOUISIANA GENERATING LLC


MIDDLETOWN POWER LLC


MONTVILLE POWER LLC


NEO CALIFORNIA POWER LLC


NEO CHESTER-GEN LLC


NEO CORPORATION


NEO FREEHOLD-GEN LLC


NEO LANDFILL GAS HOLDINGS INC.


NEO POWER SERVICES INC.


NORWALK POWER LLC


NRG AFFILIATE SERVICES INC.


NRG ARTHUR KILL OPERATIONS INC.


NRG ASIA-PACIFIC, LTD.


NRG ASTORIA GAS TURBINE OPERATIONS, INC.


NRG BAYOU COVE LLC


NRG CABRILLO POWER OPERATIONS INC.


NRG CADILLAC OPERATIONS INC.


NRG CALIFORNIA PEAKER OPERATIONS LLC


NRG CONNECTICUT AFFILIATE SERVICES INC.


NRG DEVON OPERATIONS INC.


NRG DUNKIRK OPERATIONS INC.


NRG EL SEGUNDO OPERATIONS INC.


NRG HUNTLEY OPERATIONS INC.


NRG INTERNATIONAL LLC


NRG KAUFMAN LLC


NRG MESQUITE LLC


NRG MIDATLANTIC AFFILIATE SERVICES INC.


NRG MIDDLETOWN OPERATIONS INC.


NRG MONTVILLE OPERATIONS INC.


NRG NEW JERSEY ENERGY SALES LLC


NRG NEW ROADS HOLDINGS LLC


NRG NORTH CENTRAL OPERATIONS INC.


NRG NORTHEAST AFFILIATE SERVICES INC.


NRG NORWALK HARBOR OPERATIONS INC.


NRG OPERATING SERVICES, INC.


NRG OSWEGO HARBOR POWER OPERATIONS INC.


NRG POWER MARKETING INC.


NRG ROCKY ROAD LLC


NRG SAGUARO OPERATIONS INC.


NRG SOUTH CENTRAL AFFILIATE SERVICES INC.


NRG SOUTH CENTRAL GENERATING LLC


NRG SOUTH CENTRAL OPERATIONS INC.


NRG WEST COAST LLC


NRG WESTERN AFFILIATE SERVICES INC.


OSWEGO HARBOR POWER LLC


SAGUARO POWER LLC


SOMERSET OPERATIONS INC.


SOMERSET POWER LLC


VIENNA OPERATIONS INC.


VIENNA POWER LLC




By:  /s/ George P. Schaefer

Name: George P. Schaefer

Title: Treasurer




Attest:



/s/ Tanuja M. Dehne


Name: Tanuja M. Dehne

Title: Corporate Secretary




LAW DEBENTURE TRUST COMPANY OF NEW YORK, as Trustee




By:  /s/ Adam Berman

Name: Adam Berman

Title: Vice President




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SCHEDULE A




SCHEDULE OF GUARANTEEING SUBSIDIARIES





	1.	 	Texas Genco LLC, a Delaware limited liability company






	2.	 	Texas Genco Financing Corp., a Delaware corporation






	3.	 	Texas Genco GP, LLC, a Texas limited liability company






	4.	 	New Genco GP, LLC, a Delaware limited liability company






	5.	 	New Genco LP, LLC, a Delaware limited liability company






	6.	 	Texas Genco Operating Services LLC, a Delaware limited liability company






	7.	 	Texas Genco Holdings, Inc., a Texas corporation






	8.	 	Texas Genco II, LP, a Texas limited partnership






	9.	 	Texas Genco Services, LP, a Texas limited partnership






	10.	 	GCP Funding Company, LLC, a Delaware limited liability company






	11.	 	Texas Genco LP, LLC, a Delaware limited liability company






	12.	 	Texas Genco, LP, a Texas limited partnership






	13.	 	NRG Blocker I LP, a Delaware limited partnership






	14.	 	NRG Blocker II LP, a Delaware limited partnership






	15.	 	NRG Blocker III Inc., a Delaware corporation






	16.	 	NRG Blocker IV Inc., a Delaware corporation






	17.	 	NRG Blocker V Inc., a Delaware corporation






	18.	 	NRG Blocker VI Inc., a Delaware corporation






	19.	 	NRG Blocker VII Inc., a Delaware corporation






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