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                                                                    EXHIBIT 3.A



                              AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                              ANR PIPELINE COMPANY


                     Pursuant to Sections 242 and 245 of the
                General Corporation Law of the State of Delaware

         ANR Pipeline Company (the "Corporation"), a corporation organized and
existing under the laws of the State of Delaware, hereby certifies as follows:

         1. The name of the Corporation is ANR Pipeline Company. The Corporation
was originally incorporated on July 20, 1945, under the name Michigan-Wisconsin
Pipe Line Company. The name of the Corporation was changed to Michgan Wisconsin
Pipe Line Company on September 2, 1953, and was changed to ANR Pipeline Company
on December 14, 1983.

         2. This Amended and Restated Certificate of Incorporation restates and
further amends the Certificate of Incorporation of the Corporation and has been
adopted and approved in accordance with Sections 242 and 245 of the General
Corporation Law of the State of Delaware. Stockholder approval of this Restated
Certificate of Incorporation was given by unanimous written consent of the
stockholders of the Corporation in accordance with Section 228 of the General
Corporation Law of the State of Delaware.

         3. The text of the Certificate of Incorporation, as heretofore amended,
is hereby amended and restated to read in its entirety as follows:

             FIRST: The name of the corporation is ANR Pipeline Company.

             SECOND: The address of the Corporation's registered office in the
         State of Delaware is Corporation Trust Center, 1209 Orange Street, City
         of Wilmington, New Castle County, Delaware 19801, and the name of its
         registered agent at the above address is The Corporation Trust Company.

             THIRD: The purpose of the corporation is to engage in any lawful
         act or activity for which corporations may be organized under the
         General Corporation Law of the State of Delaware.

             FOURTH: The total number of shares of stock the corporation shall
         have authority to issue is one thousand (1,000) shares of common stock
         with a par value of one dollar ($1.00) per share.


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                  Shares of stock of this corporation whether with or without
         par value, of any class or classes hereby or hereafter authorized, may
         be issued by this corporation from time to time for such consideration
         permitted by law as may be fixed from time to time by the Board of
         Directors.

             FIFTH: Unless required by the By-laws, the election of the Board of
         Directors need not be by written ballot.

             SIXTH: The Board of Directors of this corporation is expressly
         authorized to make, alter, or repeal the By-laws of the corporation,
         but the stockholders may make additional By-laws and may alter or
         repeal any By-law whether or not adopted by them.

             SEVENTH: No director of the Corporation shall be personally liable
         to the corporation or its stockholders for monetary damages for breach
         of fiduciary duty as a director, for any act or omission, except that a
         director may be liable (i) for breach of the director's duty of loyalty
         to the corporation or its stockholders, (ii) for acts or omissions not
         in good faith or that involve intentional misconduct or a knowing
         violation of law, (iii) under Section 174 of the General Corporation
         Law of the State of Delaware, or (iv) for any transaction from which
         the director derived an improper personal benefit. If the General
         Corporation Law of the State of Delaware is amended to authorize
         corporate action further eliminating or limiting the personal liability
         of directors, then the liability of the directors shall be eliminated
         or limited to the fullest extent permitted by the General Corporation
         Law of the State of Delaware, as so amended. The elimination and
         limitation of liability provided herein shall continue after a director
         has ceased to occupy such position as to acts or omissions occurring
         during such director's term or terms of office. Any amendment, repeal
         or modification of this Article Seventh shall not adversely affect any
         right of protection of a director of the Corporation existing at the
         time of such repeal or modification.

         IN WITNESS WHEREOF, ANR Pipeline Company has caused this Amended and
Restated Certificate of Incorporation to be signed by a duly authorized officer
this 7th day of March 2002.


                                       ANR PIPELINE COMPANY



                                       By:    /s/ Teresa L. McDonald
                                           -----------------------------
                                                Teresa L. McDonald
                                                  Vice President