DOMINION RESOURCES, INC. CONSOLIDATED NATURAL GAS COMPANY

EXHIBIT 4.6

DOMINION RESOURCES, INC.

CONSOLIDATED NATURAL GAS COMPANY

and

THE BANK OF NEW YORK

Trustee

Seventh Supplemental Indenture

Dated as of June 27, 2007

To Indenture dated as of April 1, 2001

between

Consolidated Natural Gas Company

and

The Bank of New York, Trustee

THIS SEVENTH SUPPLEMENTAL INDENTURE is made as of the 27^th day of June, 2007, by and between DOMINION RESOURCES, INC., a Virginia corporation, having its principal office at 120 Tredegar Street, Richmond, Virginia, 23219 (the “Company”), CONSOLIDATED NATURAL GAS COMPANY, a Delaware corporation (the “Predecessor Company”), and The Bank of New York (as successor trustee to Bank One Trust Company, National Association (“Bank One”)), as trustee (hereinafter referred to as the “Trustee”).

WITNESSETH:

WHEREAS, the Predecessor Company has heretofore executed and delivered to the Trustee an indenture, dated as of April 1, 2001, as heretofore amended, supplemented or otherwise modified (the “Indenture”);

WHEREAS, pursuant to that certain Agreement and Plan of Merger, dated as of June 27, 2007, by and among the Predecessor Company and the Company (the “Merger Agreement”), the Predecessor Company has agreed to merge with and into the Company, the parent entity of the Predecessor Company (the “Merger”), on the effective date and time of the Merger as specified in the Merger Agreement (the “Effective Time”);

WHEREAS, on the Effective Time, (i) the separate existence of the Predecessor Company will cease, and (ii) the Company will survive as the continuing entity;

WHEREAS, Section 801 of the Indenture provides that the Predecessor Company may not consolidate with or merge into any Person unless, among other things, (i) the Person expressly assumes, by a supplemental indenture, (a) the due and punctual payment of the principal of and any premium and any interest on all the Securities, and (b) the performance of every covenant of the Indenture on the part of the Predecessor Company to be performed or observed, and (ii) immediately after giving effect to such transaction, no Event of Default, and no event which, after notice or lapse of time, or both, would become an Event of Default, shall have happened and be continuing;

WHEREAS, pursuant to Section 802 of the Indenture, upon the Predecessor Company’s merger into the Company in accordance with Section 801 thereto, the Company shall succeed to, and be substituted for, the Predecessor Company and thereafter from time to time the Company may exercise each and every right and power of the Predecessor Company under the Indenture with the same effect as if the Company had been named in the Indenture as a party thereto;

WHEREAS, Section 901 of the Indenture provides that the Predecessor Company and the Trustee may enter into a supplemental indenture without the consent of any Holders of Securities to evidence the succession of another Person to the Predecessor Company, and the assumption by any such successor of the covenants of the Predecessor Company contained therein and in the Securities;

WHEREAS, to comply with Sections 801, 802 and 901 of the Indenture, the Predecessor Company desires that the Company assume, from and after the Effective Time, the due and punctual payment of the principal of and any premium and interest on all the Securities outstanding as of the date hereof and the performance and observance of each and every covenant and condition of the Indenture on the part of the Predecessor Company to be performed or observed;

WHEREAS, the Predecessor Company has delivered to the Trustee, or caused to be delivered to the Trustee on its behalf, an Officers’ Certificate and an Opinion of Counsel each stating that the Merger and this Seventh Supplemental Indenture comply with Section 801 of the Indenture and that all conditions precedent provided for in the Indenture relating to the foregoing have been complied with; and

WHEREAS, all things necessary to authorize the assumption by the Company of the Predecessor Company’s obligations under the Indenture and the Securities outstanding as of the date hereof, from and after the Effective Time, and to make this Seventh Supplemental Indenture a valid, binding and legal instrument have been done and performed and the execution and delivery hereof have been in all respects duly authorized.

NOW, THEREFORE, in consideration of the agreements and obligations set forth herein and for other good and valuable consideration, the sufficiency of which is hereby acknowledged, the parties hereto hereby mutually covenant and agree as follows:

1. Definitions. Capitalized terms used herein and not defined herein have the meaning ascribed to such terms in the Indenture.

2. Assumption of Obligations. Pursuant to Sections 801 and 802 of the Indenture, the Company hereby expressly assumes, from and after the Effective Time, the due and punctual payment of the principal of and any premium and interest on all the Securities outstanding as of the date hereof and the performance and observance of each and every covenant and condition of the Indenture on the part of the Predecessor Company to be performed or observed.

3. Succession and Substitution. Pursuant to Sections 801 and 802 of the Indenture, from and after the Effective Time, by virtue of the aforesaid assumption and the delivery of this Seventh Supplemental Indenture, the Company hereby succeeds to and is substituted for the Predecessor Company with the same effect as if it had been named in the Indenture and the Securities outstanding as of the date hereof, as a party thereto, and hereafter from time to time the Company may exercise each and every right and power of the Predecessor Company under the Indenture and the Securities outstanding as of the date hereof, in the name of the Predecessor Company or its own name; and any act or proceeding by any provision of the Indenture and the Securities outstanding as of the date hereof, required or permitted to be done by any board of officer of the Predecessor Company may be done with like force and effect by the like board or officer of the Company.

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4. Effectiveness and Operativeness. This Seventh Supplemental Indenture shall be deemed to have become effective, and the provisions provided for in this Seventh Supplemental Indenture shall be deemed to have become operative, immediately as of the Effective Time.

5. Ratification of Indenture; Seventh Supplemental Indenture Part of Indenture. The Indenture, as supplemented by this Seventh Supplemental Indenture, is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect. This Seventh Supplemental Indenture shall be deemed part of the Indenture in the manner and to the extent herein and therein provided; and all terms, conditions and provisions of the Indenture shall remain in full force and effect.

6. Evidence of Merger. Following the effectiveness of the Merger, the Company will provide the Trustee with an Assistant Corporate Secretary’s Certificate which will have attached as exhibits evidence of the consummation of the Merger issued by the Secretary of State of the State of Delaware and the Virginia State Corporation Commission.

7. Addresses. Pursuant to the authority set forth in Section 901 of the Indenture, the addresses of the Company and the Trustee specified in any provision of the Indenture shall be hereby amended and restated as follows:

8. Legend. Following the effectiveness of the Merger, the Trustee is authorized and directed to affix the following legend to any certificates relating to any Securities outstanding as of the date hereof:

EFFECTIVE AS JUNE 30, 2006 BY VIRTUE OF THE MERGER OF CONSOLIDATED NATURAL GAS COMPANY, A DELAWARE CORPORATION (“CNG”), WITH AND INTO DOMINION RESOURCES, INC., A VIRGINIA CORPORATION (“DOMINION”), AND PURSUANT TO THAT CERTAIN SEVENTH SUPPLEMENTAL INDENTURE, DATED AS OF JUNE 27, 2007, BY AND BETWEEN DOMINION, CNG, AND THE BANK OF NEW YORK (AS SUCCESSOR TRUSTEE TO BANK ONE TRUST COMPANY, NATIONAL ASSOCIATION), AS TRUSTEE, DOMINION HAS ASSUMED ALL OF THE OBLIGATIONS OF CNG WITH RESPECT TO THE SECURITIES REPRESENTED BY THIS CERTIFICATE.

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9. Governing Law. This Seventh Supplemental Indenture shall be governed by and construed in accordance with the laws of the State of New York applicable to agreements made or instruments entered into and, in each case, performed in said State, without regard to conflicts of law principles thereof.

10. Recitals; Trustee Makes No Representation. The recitals herein contained are made by the Predecessor Company and the Company and not by the Trustee and the Trustee assumes no responsibility for the correctness thereof. The Trustee makes no representation as to the validity or sufficiency of this Seventh Supplemental Indenture.

11. Headings. The section headings herein are for convenience only and shall not effect the construction thereof.

12. Counterparts. This Seventh Supplemental Indenture may be executed in any number of counterparts and by different parties hereto on separate counterparts, each of which when so executed shall be deemed to be an original and all of which taken together shall constitute but one and the same agreement.

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IN WITNESS WHEREOF, each party hereto has caused this instrument to be signed in its name and behalf by its duly authorized officer, all as of the day and year first above written.