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                                                                     EXHIBIT 3.1

                              AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                         EASTERN STATES OIL & GAS, INC.


         EASTERN STATES OIL & GAS, INC. (the "Corporation"), a corporation
organized and existing under and by virtue of the General Corporation Law of the
State of Delaware ("DGCL"), hereby certifies as follows pursuant to Sections 242
and 245 of the DGCL:

         FIRST:    The name of the Corporation is "Eastern States Oil & Gas,
                   Inc."

         SECOND:   The Corporation was originally incorporated under the name of
                   "Pamco, Inc."

         THIRD:    The original Certificate of Incorporation of the Corporation
                   was filed in the Office of the Secretary of State of the
                   State 1f Delaware (the "Secretary of State") on November 14,
                   1985.

         FOURTH:   The Corporation filed amendments to its Certificate of
                   Incorporation with the Secretary of State on April 21, 1986,
                   June 29, 1987, June 20, 1996, October 30, 1996, December 4,
                   1996, March 4, 1997, October 21, 1997, December 3, 1998, and
                   August 19, 1999.

         FIFTH:    The sole stockholder of the Corporation is Statoil Energy
                   Holdings, Inc. (the "Sole Stockholder"), a Delaware
                   corporation.

         SIXTH:    The board of directors of the Corporation, in accordance with
                   Sections 242 and 245 of the DGCL, (i) adopted and approved
                   this Amended and Restated Certificate of Incorporation
                   (including the amendments to the Corporation's Certificate of
                   Incorporation effected hereby) and (ii) proposed that the
                   Sole Stockholder adopt and approve this Amended and Restated
                   Certificate of Incorporation (including the amendments to the
                   Corporation's Certificate of Incorporation effected hereby).

         SEVENTH:  The Sole Stockholder, in accordance with Sections 242 and 245
                   of the DGCL, approved and adopted on behalf of the Sole
                   Stockholder this Amended and Restated Certificate of
                   Incorporation (including the amendments to the Corporation's
                   Certificate of Incorporation effected hereby).



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         EIGHTH:   The Sole Stockholder, in accordance with Section 228 of the
                   DGCL, approved and adopted this Amended and Restated
                   Certificate of Incorporation (including the amendments to the
                   Corporation's Certificate of Incorporation effected hereby).

         NINTH:    This Amended and Restated Certificate of Incorporation shall
                   become effective upon its filing with the Secretary of State.

         TENTH:    Effective immediately upon the filing of this Amended and
                   Restated Certificate of Incorporation in the office of the
                   Secretary of State, each outstanding share of previously
                   existing Common Stock shall be and hereby is converted into
                   and reclassified as one-half of one share of Common Stock.
                   Certificates representing reclassified shares are hereby
                   canceled and upon presentation of the canceled certificates
                   to the Corporation, the holders thereof shall be entitled to
                   receive certificate(s) representing the new shares into which
                   such canceled shares have been converted.

         ELEVENTH: The Certificate of Incorporation of the Corporation is hereby
                   amended and restated to read in its entirety as follows:


                                    ARTICLE I

                                      NAME

         The name of the Corporation is Eastern States Oil & Gas, Inc.

                                   ARTICLE II

                     REGISTERED OFFICE AND REGISTERED AGENT

         The registered office of the Corporation in the State of Delaware is
located at 1013 Centre Road in the City of Wilmington 19805, County of New
Castle. The name of its registered agent at such address is Corporation Service
Company. The principal place of business of the Corporation is 2800 Eisenhower
Avenue, Alexandria, Virginia 22314.

                                   ARTICLE III

                                     PURPOSE

         The purpose for which the Corporation is organized is to engage in any
lawful acts and activities for which corporations may be organized under the
DGCL, and the Corporation shall have the power to perform all lawful acts and
activities.


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                                   ARTICLE IV

                                 CAPITALIZATION

         The total number of shares of stock which the Corporation has authority
to issue is One Thousand (1,000) shares of common stock ("Common Stock") of the
par value of One Dollar ($1.00) per share.

                                    ARTICLE V

                              STOCKHOLDERS' RIGHTS

         (1) The holders of the Common Stock shall have the right, pro rata,
according to their total respective holdings of Common Stock and on such terms
and conditions as the board of directors may determine, to purchase or subscribe
for any of the authorized but unissued shares of Common Stock which the
Corporation may hereafter issue; provided, however, that any such right to
purchase or subscribe for any such shares of Common Stock or any such obligation
shall be nontransferable.

         (2) The holders of the Common Stock shall be entitled to vote upon all
matters submitted to a vote of the stockholders of the Corporation and shall be
entitled to one vote for each share of Common Stock held.

         (3) The right to cumulate votes for the election of directors as
provided in Section 214 of the DGCL shall not be granted and is hereby expressly
denied.

         (4) The private property of the stockholders of the Corporation shall
not be subject to the payment of any of the debts or liabilities of the
Corporation.

                                   ARTICLE VI

                               BOARD OF DIRECTORS

         Subject to the restrictions that the number of directors shall not be
less than two (2) or, such larger number as from time to time may be required by
the laws of the State of Delaware the number of directors may be fixed from time
to time by the Bylaws of the Corporation.



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                                   ARTICLE VII

                    INDEMNIFICATION OF OFFICERS AND DIRECTORS

         (1) To the full extent permitted by Section 102(b)(7) of the DGCL, the
personal liability for monetary damages for breach of fiduciary duty as a
director to the Corporation or its stockholders of any person who is or was a
director shall be eliminated; provided, however, that such personal liability
shall not be eliminated hereby (i) for any breach of the director's duty of
loyalty to the Corporation or its stockholders, (ii) for acts or omissions not
in good faith or which involve intentional misconduct or a knowing violation of
law, (iii) under Section 174 of the DGCL or (iv) for any transaction from which
the director derived an improper personal benefit.

         (2) If the DGCL is hereafter amended to authorize corporate action
further limiting or eliminating the personal liability of directors, then the
personal liability of the directors to the Corporation or its stockholders shall
be limited or eliminated to the full extent permitted by the DGCL, as so amended
from time to time.

         (3) In addition, subject to the approval of the board of directors, the
Corporation may indemnify each employee and agent of the Corporation and all
other persons whom the Corporation is authorized to indemnify under the
provisions of the DGCL.

                                  ARTICLE VIII

                                   MANAGEMENT

         This article EIGHTH is inserted for the management of the business and
the conduct of the affairs of the Corporation, and for further definition,
limitation and regulation of the powers of the Corporation and of its directors
and stockholders.

         The following powers shall not be vested in the directors but shall be
reserved in and exercised only by the stockholders of the Corporation:

         (1) The power to declare dividends.

         (2) The power to borrow money and/or to mortgage, pledge or otherwise
encumber assets of the Corporation.

         (3) The power to amend the Bylaws of the Corporation.

         (4) The power to sell all or substantially all of the assets of the
Corporation or to merge, consolidate or to liquidate the Corporation.

         (5) The power to grant proxies to vote shares of stock owned or held by
the Corporation.


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         (5) The power to guarantee debts or obligations of any other person,
corporation or other entity.

                                   ARTICLE IX

                           AMENDMENT OF CERTIFICATE OF
                                  INCORPORATION

         The Corporation reserves the right to amend or repeal any provision
contained in this Amended and Restated Certificate of Incorporation in the
manner prescribed by the laws of the State of Delaware. All rights herein
conferred are granted subject to this reservation.

         IN WITNESS WHEREOF, this Amended and Restated Certificate of
Incorporation has been executed for and on behalf and in the name of the
Corporation by its officers thereunto duly authorized on August 26, 1999.


                                                   /s/ KERRY W. ECKSTEIN
                                                   -----------------------------
                                                   Kerry W. Eckstein
                                                   Secretary



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