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                                                                     EXHIBIT 3.B



                                     BY-LAWS

                                       OF

                              ANR PIPELINE COMPANY

                                   AS AMENDED

                                 AUGUST 29, 1991
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                                     BY-LAWS

                                       OF

                              ANR PIPELINE COMPANY

                             A DELAWARE CORPORATION


                              --------------------


                                    ARTICLE I

                                     OFFICES

         SECTION 1.1 Registered Office and Agent. The registered office of the
corporation in the State of Delaware shall be in Wilmington, Delaware. The name
of the registered agent is the Corporation Trust Company.

         SECTION 1.2 Other Offices. The Corporation may also have offices at
such other places both within and without the State of Delaware as the Board of
Directors may from time to time determine or the business of the corporation may
require.

                                   ARTICLE II

                            MEETINGS OF SHAREHOLDERS

         SECTION 2.1 Annual Meetings. The annual meetings of the stockholders
for the election of directors and for the transaction of such other business as
may properly come before the meeting shall be held at such place, date and hour
as shall be designated in the notice thereof.

         SECTION 2.2 Special Meetings. Except as otherwise prescribed by law,
special meetings of the stockholders, for any purpose or purposes, may be called
by the Chairman, or in his absence by the President, or by the Secretary at the
request of the Board of Directors. The notice of the special meeting shall state
the time, place and purposes of the proposed special meeting. Business
transacted at a special meeting shall be confined to the purposes stated in the
notice.

         SECTION 2.3 Place of Meetings. Each meeting of the stockholders for the
election of Directors shall be held at the principal office of the corporation
in Detroit, Michigan, unless the Board of Directors shall by resolution
designate any other place, within or without the State of Delaware, as the place
of such meeting. Meetings of stockholders for any other purpose
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may be held at any such place, within or without the State of Delaware, and at
such time as shall be stated in the notice of the meeting, or in a duly executed
waiver thereof.

         SECTION 2.4 Notice of Meetings. Except as otherwise provided by law,
written notice of time, place and, in case of a special meeting, the purpose or
purposes for which the meeting is called, shall be given not less than ten nor
more than sixty days before the date of the meeting to each stockholder of
record entitled to vote at the meeting.

         SECTION 2.5 Stockholder List. At least ten days before every meeting of
stockholders, the officer of agent having charge of the stock transfer books
shall prepare a complete list of the stockholders entitled to vote at said
meeting, arranged in alphabetical order, with the address of, and number of
shares registered in the name of each. Such list shall be open to examination of
any stockholder during ordinary business hours, for any purpose germane to the
meeting, for a period of at least ten days prior to the meeting, either at a
place in the city where such meeting shall be held, which place shall be
specified in the notice of meeting or, if not so specified, at the place where
the meeting is to be held; and the list shall be produced and kept at the time
and place of the meeting during the whole time thereof, and may be inspected by
any such stockholder who may be present.

         SECTION 2.6 Quorum. The holders of a majority of the stock issued and
outstanding and entitled to vote there at, present in person or represented by
proxy, shall be requisite for, and shall constitute, a quorum at all meetings of
the stockholders of the corporation for the transaction of business, except as
otherwise provided by law or these By-Laws.

         SECTION 2.7 Proxies. At every meeting of stockholders, each stockholder
has the right to vote in person or by proxy. Such proxy shall be appointed by an
instrument in writing subscribed by stockholder or his authorized agent or
representative, and bearing a date not more than three (3) years prior to such
meeting, unless the proxy provides for a longer period. Each proxy shall be
filed with the Secretary of the corporation prior to or at the time of the
meeting.

         SECTION 2.8 Voting. Each outstanding share is entitled to one vote on
each matter submitted to a vote unless otherwise provided in the Certificate of
Incorporation. When a quorum is present at any meeting of the stockholders, the
vote of the holders of a majority of the stock having voting power present in
person or represented by proxy shall decide any question brought before such
meeting, unless the question is one upon which, by provision of law or these
By-laws, a different vote is required, in which case such provision shall govern
and control the decision of such question. Directors of the corporation shall be
elected by a plurality of the votes cast at an election.

         SECTION 2.9 Voting of Certain Shares. Shares standing in the name of
another corporation, domestic or foreign, and entitled to vote may be voted by
such officer, agent, or proxy as the by-laws of such corporation may prescribe,
or, in the absence of such provision, as the Board of Directors of such
corporation may determine.

         SECTION 2.10 Action Without Meeting. Any action required or permitted
to be taken at any annual or special meeting of stockholders of the corporation
may be taken without a
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meeting, without prior notice and without a vote, if a consent in writing,
setting forth the action so taken, shall be signed by the holders of outstanding
stock having not less than the minimum number of votes that would be necessary
to authorize or to take such action at a meeting at which all shares entitled to
vote thereon were present and voted. Such consent shall be filed with the
minutes of the proceedings of the stockholders. Prompt notice of the taking of
corporate action without a meeting by less than unanimous written consent shall
be given to those stockholders who have not consented in writing.

         SECTION 2.11 Presiding Officers. The Chairman, or in his absence, the
President, shall call the meeting of the stockholders to order and shall act as
chairman thereof. In the absence of both the Chairman and the President, the
stockholders present at the meeting shall elect a chairman. The Secretary shall
act as a secretary of all meetings of stockholders. In the absence of the
Secretary at any meeting of stockholders, the presiding officer may appoint any
person to act as secretary of the meeting.

                                   ARTICLE III

                               BOARD OF DIRECTORS

         SECTION 3.1 Management Responsibility. The business and affairs of the
corporation shall be managed by the Board of Directors except as otherwise
provided by law or by the Certificate of Incorporation.

         SECTION 3.2 Number: Elections: Term. The Board of Directors shall
consist of no more than eight members. The number of Directors may be increased
or decreased from time to time by resolution of the Board of Directors. The
Directors shall be elected at the annual meeting of the stockholders, or at any
adjournment thereof, or at special meetings of stockholders held in accordance
with Section 2.2 of Article II of these By-Laws. Each Director elected shall
hold office until the succeeding annual meeting and until his successor shall be
elected and shall qualify, or until his earlier resignation or removal.

         SECTION 3.3 Resignation and Vacancies. Any Director may resign at any
time by giving written notice to the corporation. Any such resignation shall
take effect a the date of the receipt of such notice or at any later time
specified therein, and, unless otherwise specified therein the acceptance of
such resignation shall not be necessary to make it effective. Any vacancy
occurring in the Board of Directors may be filled by an affirmative vote of a
majority of the remaining Directors even though less than a quorum of the Board
of Directors, or by the sole remaining Director. A directorship to be filled
because of an increase in the number of Directors to fill a vacancy may be
filled by the Board of a term of office continuing only until the next election
of Directors by the stockholders.

         SECTION 3.4 Regular Meetings. A regular meeting of the Board of
Directors shall be held as soon as practicable after the annual meeting of
stockholders without further notice. The Board of Directors may provide, by
resolution, the time and place for the holding of additional regular meetings
without other notice than such resolution.
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         SECTION 3.5 Special Meetings. Special meetings of the Board of
Directors may be called and the time and place thereof designated by the
Chairman or the President. Except as otherwise provided by law, written notice
of the time and place of such special meeting of the Board of Directors shall be
given at least two days prior to the time of holding the meeting. The attendance
of a Director at any meeting shall constitute a waiver of notice of such
meeting, except where a Director attends a meeting for the express purpose of
objecting to the transaction of any business because the meeting is not lawfully
called or convened. Neither the business to be transacted at, nor the purpose
of, any special meeting of the Board of Directors need be specified in any
notice or waiver of notice of such meeting except that notice shall be given of
any proposed amendment to the By-Laws or with respect to any other matter where
notice is required by law.

         SECTION 3.6 Quorum. At each meeting of the Board of Directors, the
presence of not less than a majority of the whole Board shall be necessary and
sufficient to constitute a quorum for the transaction of business, and the act
of a majority of the Directors present at any meeting at which there is a quorum
shall be the act of the Board of Directors, except as may be otherwise
specifically provided by law. If a quorum shall not be present at any meeting of
Directors, the Directors present there at may adjourn the meeting from time to
time, without notice other than announcement at the meeting until a quorum shall
be present. A member of the Board may participate in any meeting of the Board,
or of any committee thereof, by means of conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other. Participation in a meeting pursuant to this
Subsection constitutes presence in person at the meeting.

         SECTION 3.7 Action Without Meeting. An action required or permitted to
be taken at any meeting of the Board of Directors, or of any committee of the
Board, may be taken without a meeting if a written consent thereto is signed by
all members of the Board or of such committee, as the case may be, and such
written consent is filed with the minutes of proceedings of the Board or
committee. Such consent shall have the same effect as a vote of the Board or
committee for all purposes.

         SECTION 3.8 Salary and Expenses. Directors shall not receive any stated
salary for their services as such. Members of the Board of Directors shall be
allowed their reasonable traveling expenses when actually engaged in the
business of the corporation. Members of any committee may be allowed like
expenses for attending committee meetings. Nothing herein contained shall be
construed as precluding any Director from serving the corporation in any other
capacity and receiving compensation therefor.

                                   ARTICLE IV

                                     NOTICES

         SECTION 4.1 Manner of Notice to Directors. Whenever under the
provisions of law, the Certificate of Incorporation, or these By-laws, notice is
required to be given to any Director, such notice may be given in writing by
personal delivery to the business address of
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such Director; and such notice shall be deemed to be given when it is thus
delivered. Notice may also be given in writing by mail addressed to such
Director at his business address, and such notice shall be deemed to be given at
the time when it is deposited in the United States mail in a sealed envelope,
with first-class postage affixed thereto. Notice to Directors may also be given
by telephone or telegram. It shall be the duty of every Director to furnish the
Secretary with his business address and to notify the Secretary of any change
therein.

         SECTION 4.2 Notice of Stockholders. Whenever under the provisions of
law, the Articles of Incorporation, or these By-Laws, notice is required to be
given to any stockholder, that requirement of notice shall not be construed to
require personal delivery, and such notice may be given, in writing, by mail
addressed to such stockholder at the address of such stockholder as it appears
in the stock transfer books of the corporation. Such notice shall be deemed to
be given at the time when it is deposited in the United States mail in a sealed
envelope, with first-class postage affixed thereto.

         SECTION 4.3 Waiver of Notice. Whenever any notice is required to be
given under the provisions of law, the Certificate of Incorporation, or these
By-Laws, a waiver thereof in writing signed by the person or persons entitled to
said notice, whether before or after the time stated therein, shall be deemed
equivalent thereto.

                                    ARTICLE V

                                    OFFICERS

         SECTION 5.1 Designations. The officers of the corporation shall be a
Chairman of the Board, a President, such number of Vice Presidents (including
any Executive Vice Presidents and any Senior Vice Presidents) as the Board of
Directors may determine from time to time, a Controller, a Treasurer, and a
Secretary. Two or more offices may be held by the same person, except as
otherwise provided by law.

     The Board of Directors may elect or appoint such other officers (including
a Vice Chairman of the Board, one or more Assistant Vice presidents, one or more
Assistant Controllers, one or more Assistant Treasurers and one or more
Assistant Secretaries) as it deems necessary, who shall have such authority and
shall perform such duties as the Board of Directors may prescribe.

     If additional officers are elected or appointed during the year, each of
them shall hold office until the next annual meeting of the Board of Directors
at which officers are regularly elected or appointed and until his successor is
elected or appointed or until his earlier death or resignation or removal in the
manner hereinafter provided.

         SECTION 5.2 Election and Term of Office. The officers of the
corporation to be elected by the Board of Directors shall be elected annually by
the Board of Directors at the first meeting of the Board of Directors held after
each annual meeting of the stockholders. If the election of officers shall not
be held at such meeting, such election shall held as soon thereafter
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as convenient. Each officer shall hold office until his successor shall have
been duly elected and shall have qualified or until his death or until he shall
resign or shall be have been removed in the manner hereinafter provided.

         SECTION 5.3 Resignation and Removal. Any officer may resign at any time
by giving written notice to the Chairman of the Board, the President or the
Secretary of the corporation, and such resignation shall take effect at the time
specified therein or, if the time when it shall become effective shall not be
specified therein, then it shall take effect when accepted by action of the
Board. Except as aforesaid, the acceptance of such resignation shall not be
necessary to make it effective.

     Any officer may be removed by the Board of Directors whenever, in its
judgment, the best interest of the corporation will be served thereby, but such
removal shall be without prejudice to the contract rights, if any, of the person
so removed. Election or appointment of an officer shall not of itself create
contract rights.

         SECTION 5.4 Vacancies. A vacancy in any office because of death,
resignation, removal, disqualification or otherwise may be filled by the Board
of Directors for the unexpired portion of the term.

         SECTION 5.5 Chairman of the Board. The Chairman of the Board shall
preside at all meetings of the Board of Directors and of the stockholders at
which he is present.

         SECTION 5.6 Vice Chairman of Board (if any). The Vice Chairman of the
Board shall preside at all meetings of the Board of Directors and of the
stockholders in the absence of the Chairman of the Board and have such powers
and duties as shall be prescribed by the Board of Directors and the Chairman of
the Board.

         SECTION 5.7 President. The President shall have general charge of the
business and affairs of the corporation and shall preside at meetings of the
Board of Directors and of the stockholders in the absence of the Chairman of the
Board or the Vice Chairman of the Board (if any).

         SECTION 5.8 Vice Presidents: Any Vice President shall have such powers
and duties as shall be prescribed by the President, the Chairman of the Board or
the Board of Directors.

         SECTION 5.9 Treasurer. The Treasurer shall have charge and custody of
and be responsible for all funds and securities of the corporation.

         SECTION 5.10 Controller. The Controller shall be in charge of the
accounts of the corporation and shall perform such duties as from time to time
may be assigned to him by the President, the Chairman of the Board or the Board
of Directors.

         SECTION 5.11 Secretary. The Secretary shall keep the records of all
meetings of the stockholders and of the Board of Directors and the Executive
Committee (if any). He, or any
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Assistant Secretary, shall affix the seal of the corporation to all deeds,
contracts, bonds or other instruments requiring the corporate seal, and when the
same shall have been signed on behalf of the corporation by a duly authorized
officer, shall be attested by his or an Assistant Secretary's signature.

                                   ARTICLE VI

                     INDEMNIFICATION OF DIRECTORS, OFFICERS,
                 AGENTS AND OTHER PERSONS; RELIANCE UPON RECORDS

         SECTION 6.1 Indemnification. The corporation shall indemnify its
officers, directors, employees, agents, and other persons to the fullest extent
to which corporations are empowered to indemnify such persons under the laws of
Delaware, as the same may from time to time be amended, except as such
indemnification may be limited by the Certificate of Incorporation.

                                   ARTICLE VII

                           CERTIFICATES FOR STOCK AND
                                 THEIR TRANSFER

         SECTION 7.1 Certificates of Stock. Every stockholder shall be entitled
to a certificate, in such form as the Board of Directors shall from time to time
approve, signed by the Chairman or President or a Vice President and by the
Secretary or an Assistant Secretary. Any or all of the signatures on the
certificate may be facsimile. In case any officer, transfer agent of registrar
who has signed or whose facsimile signature has been placed upon a certificate
shall have ceased to be such officer, transfer agent or registrar before such
certificate is used, it may be issued by the corporation with the same effect as
if he were such officer, transfer agent or registrar at the date of such issue.

         SECTION 7.2 Replacement of Lost or Destroyed Certificates. The Board of
Directors may direct a new certificate or certificates to be issued in place of
any certificate or certificates theretofore issued by the corporation alleged to
have been lost or destroyed, upon the making of an affidavit by the person
claiming the certificate to be lost, stolen, or destroyed as to his ownership of
the certificate and of the facts as to its loss, theft, or destruction.

         SECTION 7.3 Transfer of Stock. Upon surrender to the corporation or the
Transfer Agent of the corporation of a certificate for shares duly endorsed or
accompanied by proper evidence of succession, assignment, or authority to
transfer, it shall be the duty of the corporation to issue a new certificate to
the person entitled thereto, cancel the old certificate and record the
transaction upon its books.

         SECTION 7.4 Fixing Record Date. In order that the corporation may
determine the stockholders entitled to notice of or to vote at any meeting of
stockholders or any
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adjournment thereof or to express consent to corporate action in writing without
a meeting, or entitled to receive payment of any dividend or other distribution
or allotment of any rights, or entitled to exercise any rights in respect of any
change, conversion or exchange of stock or for the purpose of any other lawful
action, the Board of Directors may fix, in advance, a record date, which shall
not be more than sixty nor less than ten days before the date of such meeting
nor more than sixty days prior to any other action. A determination of
stockholders of record entitled to notice of or to vote at a meeting of
stockholders shall apply to any adjournment of the meeting; provided, however,
that the Board of Directors may fix a new record date for the adjourned meeting.

         SECTION 7.5 Record Ownership of Stock: The corporation shall be
entitled to treat the person in whose name any share of stock is registered as
the owner thereof, for all purposes, and shall not be bound to recognize any
equitable or other claim to, or interest in, such share on the part of any other
person, whether or not it shall have notice thereof, except as otherwise
expressly provided by the laws of Delaware.

                                  ARTICLE VIII

                               GENERAL PROVISIONS

         SECTION 8.1 Dividends. Subject to the statutes of the State of
Delaware, the Board of Directors may declare and pay dividends or make other
distributions in cash, its securities, or its property.

         SECTION 8.2 Books and Records. The corporation shall keep current and
complete books and records of account and shall keep minutes of the proceedings
of the stockholders and Board of Directors, and shall keep at its registered
office or principal place of business, or at the office of its transfer agent or
registrar, a record of its stockholders, the names and addresses of all
stockholders and the number and class of the shares held by each.

         SECTION 8.3 Checks and Notes. All checks or demands for money and notes
of the corporation shall be signed by such officer or officers or such other
person or persons as the Board of Directors may from time to time designate.

         SECTION 8.4 Fiscal Year. The fiscal year of the corporation shall be
the calendar year.

         SECTION 8.5 Seal. The corporation shall have a corporate seal in a form
which shall be approved by the Board of Directors.

         SECTION 8.6 Voting of Stock. Unless otherwise ordered by the Board of
Directors, the Chairman, the President, the Executive Vice Presidents, or any
Vice President of the corporation shall have full power and authority to act and
vote, in the name and on behalf of this corporation, at any meeting of
stockholders of any corporation in which the corporation may hold stock and at
any such meeting shall possess and may exercise any and all of the rights and
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powers incident to the ownership of such stock, and shall have full power and
authority to execute, in the name of and on behalf of this corporation, proxies
authorizing any suitable person or persons to act and to vote at any meeting of
stockholders of any corporation in which this corporation may hold stock, and at
any meeting the person or persons so designated shall possess and may exercise
any and all of the rights and powers incident to the ownership of such stock.

         SECTION 8.7 Amendment of By-Laws. These By-Laws may be altered, amended
or repealed at any meeting of the Board of Directors at which a quorum is
present by a majority vote of the Directors. Nothing in this Article shall be
construed to limit the power of the stockholders to amend, alter or rescind any
of the By-Laws of the corporation.