<PAGE>   1
                                                                    EXHIBIT 10.6





                                     MICHCON

                         SUPPLEMENTAL DEATH BENEFIT AND

                             RETIREMENT INCOME PLAN





                (AS AMENDED AND RESTATED EFFECTIVE APRIL 1, 1997)



<PAGE>   2

<TABLE>
<CAPTION>
                                TABLE OF CONTENTS

SECTION                                                                                                           PAGE
-------                                                                                                           ----
<S>                                                                                                               <C>
 ARTICLE 1 ......................................................................................................  1
      Title
 ARTICLE 2 ......................................................................................................  1
      Definitions
 ARTICLE 3 ......................................................................................................  6
      Purpose
 ARTICLE 4 ......................................................................................................  6
      Effective Date
 ARTICLE 5 ......................................................................................................  6
      Participation
 ARTICLE 6 ......................................................................................................  7
      Benefits
 ARTICLE 7 ...................................................................................................... 10
      Conditions for Benefits
 ARTICLE 8 ...................................................................................................... 12
      Unfunded Plan
 ARTICLE 9 ...................................................................................................... 13
      Assignment
 ARTICLE 10 ..................................................................................................... 13
      Administration
 ARTICLE 11 ..................................................................................................... 14
      Amendment, Suspension or Termination
 ARTICLE 12 ..................................................................................................... 14
      Legal Fees and Expenses
 ARTICLE 13 ..................................................................................................... 15
      No Employment Rights and Not a Contract to Continue in
           Office
</TABLE>


<PAGE>   3

                                     MICHCON

                         SUPPLEMENTAL DEATH BENEFIT AND

                             RETIREMENT INCOME PLAN

                      (as amended effective April 1, 1997)

                                   ARTICLE I

                                      TITLE

     The title of this plan shall be the "MichCon Supplemental Death Benefit and
Retirement Income Plan."

                                    ARTICLE 2

                                  DEFINITIONS

     The following words and phrases used herein shall have the following
respective meanings unless the context clearly requires otherwise:

     (1)  Board: The Board of Directors of MCN Energy Group Inc.

     (2)  Cause: Cause shall mean repeated material breaches of an Employee's
          duties of employment which are not cured after receipt by the Employee
          of written notice specifying such breaches or the Employee's
          conviction of a felony involving moral turpitude.

     (3)  Change of Control: Change of Control shall mean:

          (a)  The acquisition by any individual, entity or group (within the
               meaning of Section 13(d)(3) or 14(d)(2) of the Securities
               Exchange Act of 1934 as amended (the "Exchange Act")) (a
               "Person") of beneficial ownership (within the meaning of Rule
               13d-3 promulgated under the Exchange Act) of 20% or more of
               either (1) the then outstanding shares of common stock of MCN
               Energy Group Inc. (the "Outstanding MCN Common Stock") or (ii)
               the combined voting power of the then outstanding voting
               securities of MCN Energy Group Inc. entitled to vote generally in
               the election of directors (the "Outstanding MCN Voting
               Securities"): provided,


<PAGE>   4

               however, that the following acquisitions shall not constitute a
               Change of Control: (i) any acquisition directly from MCN Energy
               Group Inc. (excluding an acquisition by virtue of the exercise of
               a conversion privilege), (ii) any acquisition by MCN Energy Group
               Inc., (iii) any acquisition by any employee benefit plan (or
               related trust) sponsored or maintained by MCN Energy Group Inc.
               or any corporation controlled by MCN Energy Group Inc. or (iv)
               any acquisition by any corporation pursuant to a reorganization,
               merger or consolidation, if, following such reorganization,
               merger or consolidation, the conditions described in clauses (i),
               (ii) and (iii) of subsection (c) of this Section 2 are satisfied;
               or

          (b)  Individuals who, as of the date hereof, constitute the Board of
               Directors of MCN Energy Group Inc. (the "Incumbent Board") cease
               for any reason to constitute at least a majority of the Board;
               provided, however, that any individual becoming a director
               subsequent to the date hereof whose election, or nomination for
               election by MCN Energy Group Inc.'s shareholders, was approved by
               a vote of at least a majority of the directors then comprising
               the Incumbent Board shall be considered as though such individual
               were a member of the Incumbent Board, but excluding, for this
               purpose, any such individual whose initial assumption of office
               occurs as a result of either an actual or threatened election
               contest (as such terms are used in Rule 14a-11 of Regulation
               14A promulgated under the Exchange Act) or other actual or
               threatened solicitation of proxies or consents by or on behalf of
               a Person other than the Board; or

          (c)  Approval by the shareholders of MCN Energy Group Inc. of a
               reorganization, merger or consolidation, in each case, unless,
               following such reorganization, merger or consolidation, (1) more
               than 60% of, respectively, the then outstanding shares of common
               stock of the


<PAGE>   5

               corporation resulting from such reorganization, merger or
               consolidation and the combined voting power of the then
               outstanding voting securities of such corporation entitled to
               vote generally in the election of directors is then beneficially
               owned, directly or indirectly, by all or substantially all of the
               individuals and entities who were the beneficial owners,
               respectively, of the Outstanding MCN Common Stock and Outstanding
               MCN Voting Securities immediately prior to such reorganization,
               merger or consolidation is substantially the same proportions as
               their ownership, immediately prior to such reorganization, merger
               or consolidation, of the Outstanding MCN Common Stock and
               Outstanding MCN Voting Securities, as the case may be, (ii) no
               Person (excluding MCN Energy Group Inc., any employee benefit
               plan or related trust sponsored or maintained by MCN Energy Group
               Inc. or any corporation controlled by MCN Energy Group Inc. or
               such corporation resulting from such reorganization, merger or
               consolidation and any Person beneficially owning, immediately
               prior to such reorganization, merger or consolidation, directly
               or indirectly, 20% or more of the Outstanding MCN Common Stock or
               Outstanding MCN Voting Securities, as the case may be)
               beneficially owns directly or indirectly, 20% or more of,
               respectively, the then outstanding shares of common stock of the
               corporation resulting from such reorganization, merger or
               consolidation or the combined voting power of the then
               outstanding voting securities of such corporation entitled to
               vote generally in the election of directors and (iii) at least a
               majority of the members of the board of directors of the
               corporation resulting from such reorganization, merger or
               consolidation were members of the Incumbent Board at the time of
               the execution of the initial agreement providing for such
               reorganization, merger or consolidation; or


<PAGE>   6

          (d)  Approval by the shareholders of MCN Energy Group Inc. of (i) a
               complete liquidation or dissolution of MCN Energy Group Inc. or
               (ii) the sale or other disposition of all or substantially all of
               the assets of MCN Energy Group Inc., other than to a corporation,
               with respect to which following such sale or other disposition,
               (A) more than 60% of, respectively, the then outstanding shares
               of common stock of such corporation and the combined voting power
               of the then outstanding voting securities of such corporation
               entitled to vote generally in the election of directors is then
               beneficially owned, directly or indirectly, by all or
               substantially all of the individuals and entities who were the
               beneficial owners, respectively, of the Outstanding MCN Common
               Stock and Outstanding MCN Voting Securities immediately prior to
               such sale or other disposition in substantially the same
               proportion as their ownership, immediately prior to such sale or
               other disposition, of the Outstanding MCN Common Stock and
               Outstanding MCN Voting Securities, as the case may be, (B) no
               Person (excluding MCN Energy Group Inc., any employee benefit
               plan or related trust sponsored or maintained by MCN Energy Group
               Inc. or any corporation controlled by MCN Energy Group Inc., or
               such corporation resulting from such reorganization, merger or
               consolidation, and any Person beneficially owning, immediately
               prior to such sale or other disposition, directly or indirectly,
               20% of more of the Outstanding MCN Common Stock or Outstanding
               MCN Voting Securities, as the case may be) beneficially owns,
               directly or indirectly, 20% or more of, respectively, the then
               outstanding shares of common stock of such corporation and the
               combined voting power of the then outstanding voting securities
               of such corporation entitled to vote generally in the election of
               directors and (C) at least a majority of the members of the
               board of directors of such


<PAGE>   7

               corporation were members of the Incumbent Board at the time of
               the execution of the initial agreement or action of the Board
               providing for such sale or other disposition of assets of MCN
               Energy Group Inc.

     (4)  Committee: The Compensation Committee of the Board.

     (5)  Company: Michigan Consolidated Gas Company.

     (6)  Dependent Child: A natural born or legally adopted child, stepchild or
          foster child of an Employee, including children conceived at the date
          of death, which child is unmarried, is not in the armed forces of any
          country, has not attained the age of 21, and prior to the death of the
          Survivor was dependent upon such Survivor for his or her principal
          support and maintenance and, if a stepchild or foster child, resided
          in such Survivor's household. If, with respect to an Employee, there
          are more than four persons who qualify under the preceding sentence at
          anytime, only the four youngest such persons shall be treated as
          qualifying.

     (7)  Directors: Members of the Board who are not also employees of the
          Company or of a Subsidiary.

     (8)  Employees: Key salaried employees of the Company or a Subsidiary who
          are employed in an executive, administrative, or professional
          capacity.

     (9)  Final Annual Salary: The regular basic annual salary for an Employee
          before any payroll deductions, Section 401(k) contributions,
          non-qualified deferred compensation contributions, or cafeteria plan
          election, but excluding bonuses, awards and severance payments. This
          amount shall be determined at the time the employment of the Employee
          ceases as a result of retirement, termination or death.

     (10) Good Reason: Good Reason means (i) a significant change in the
          Employee's authority, duties, responsibilities or status within MCN
          from those which existed immediately prior to the Change in Control;
          (ii) a change (other than a bona fide promotion) in the Employee's
          title or office; (iii) a reduction in the Employee's compensation or
          benefits existing immediately prior to the Change in Control; (iv) a
          change in the Employee's assigned place of employment requiring
          physical relocation,


<PAGE>   8

          or a material change in the Employee's business travel obligations;
          (v) any similar significant change in the requirements,
          responsibilities or compensation of the Employee from the arrangements
          immediately prior to the Change in Control imposed by MCN without the
          express written consent of the Employee; or (vi) any other changes in
          working conditions that a reasonable man holding a similar position
          would find untenable.

     (11) MCN: MCN Energy Group Inc.

     (12) Plan: MichCon Supplemental Death Benefit and Retirement Income Plan.

     (13) Subsidiary: Any corporation in which the Company owns, directly or
          indirectly, stock possessing 50 percent or more of the total combined
          voting power of all classes of stock.

     (14) Survivor: The Employee or the Employee's spouse (if any) whose death
          occurs last.

                                   ARTICLE 3

                                     PURPOSE

     The purpose of the Plan is to improve the ability of the Company and its
Subsidiaries to attract and retain executives and directors.

                                    ARTICLE 4

                                 EFFECTIVE DATE

             The effective date of the Plan shall be June 22, 1988.

                                   ARTICLE 5

                                 PARTICIPATION

     Participation in the Plan is limited to Employees and Directors who are
recommended by the Committee and approved by the Board. No person shall have a
right to participate in the Plan without approval by the Board. Participation in
the Plan shall be evidenced by a written agreement




<PAGE>   9

executed between the Company and the Employee or Director. No person eligible
for benefits under this Plan as an Employee shall be eligible for benefits under
this Plan as a Director.

     No benefit shall be payable to or on behalf of any Director who dies or
retires on or after April 1, 1997.


                                    ARTICLE 6

                                    BENEFITS

A. Pre-Retirement Death Benefit

     Provided the conditions specified in Article 7, Section A are satisfied,
the Company will pay solely to the surviving spouse of an Employee who
participated in the Plan, a pre-retirement death benefit of 1/24th of the
Employee's Final Annual Salary during the month of the Employee's death and
monthly thereafter through and including the month the Employee would have
attained age 65, and thereafter, monthly payments of 1/60th of the Employee's
Final Annual Salary through and including the month in which the Employee would
have attained age 75. All such payments will be made only during the lifetime of
the Employee's surviving spouse and will cease upon the death of said spouse.
With respect to Directors, provided the conditions specified in Article 7,
Section A are satisfied, the Company will pay solely to the surviving spouse of
a Director who participated in the Plan, a pre-retirement death benefit of
$100,000 at the time of the Director's death. Payment will be made only to the
Director's surviving spouse and no payment will be made if there is no surviving
spouse.

B. Post-Retirement Benefit

     Provided the conditions specified in Article 7, Section B are satisfied,
the Company will pay to an Employee or Director who participated in the Plan, a
post-retirement benefit. An Employee who retires prior to age 62 and the
Employee's surviving spouse are not eligible (without approval of the Committee)
to begin receiving any post-retirement benefit until the date that the Employee
attains or would have attained age 62 had the Employee lived. A Director who
ceases to hold office as a Director prior to age 65 is not eligible (without
approval of the Committee) to receive any post-retirement benefit. If such
approval is


<PAGE>   10

obtained, post-retirement benefits will begin on the date the Director attains
or would have attained age 65 had the Director lived, unless otherwise approved
by the Committee.

     An Employee shall elect, at least 30 days prior to the Employee's
retirement (or at least 30 days prior to attaining age 62 if the second
paragraph of Article 7, Section D applies to the Employee), on a form approved
by the Committee, to receive a post-retirement benefit pursuant to any one of
the following options. A Director shall elect, at least 30 days prior to the
Director ceasing to hold office as a Director (or at least 30 days prior to
attaining age 65 if the third paragraph of Article 7, Section D applies to the
Director), on a form approved by the Committee, to receive a post-retirement
benefit pursuant to either Option A or C.

1.   Supplemental Retirement Benefit Options
     OPTION A. The Company will pay to an Employee, in equal monthly payments,
     20% of the Employee's Final Annual Salary each year for each of the first
     10 years following the Employee's retirement from the Company or a
     Subsidiary or following the Employee's attainment of age 62, whichever is
     later. With respect to Directors, the Company will pay to a Director, in
     equal monthly payments, $10,000 each year for each of the first 10 years
     following the Director's ceasing to hold office as a Director. Such
     payments will be made only to the Employee or Director, or in the event of
     the Employee's or Director's death, to the Employee's or Director's
     surviving spouse, and upon the death of the survivor thereof shall cease.

                                       OR

     OPTION B. The Company will pay to an Employee, in equal monthly payments,
     15% of the Employee's Final Annual Salary each year for each of the first
     15 years following the Employee's retirement from the Company or a
     Subsidiary or following the Employee's attainment of age 62, whichever is
     later. Such payments will be made only to the Employee, or in the event of
     the Employee's death, to the Employee's surviving spouse, and upon the
     death of the survivor thereof shall cease.

                                       OR

2.   Post-Retirement Death Benefit Option


<PAGE>   11


     OPTION C. The Company will pay solely to an Employee's surviving spouse,
     the sum of 332% of the Employee's Final Annual Salary upon the later of
     the Employee's death or the date the Employee would have attained age 62
     had the Employee lived. With respect to Directors, the Company will pay
     solely to the Director's surviving spouse, the sum of $100,000 upon the
     death of a Director if the death occurs after the Director ceased to hold
     office as a Director. No payment will be made if there is no surviving
     spouse.

                                       OR

     OPTION D. The Company will pay solely to an Employee's surviving spouse, in
     equal monthly payments, 42% of the Employee's Final Annual Salary each year
     for each of the first 10 years following the later of the Employee's death
     or the date the Employee would have attained age 62 had the Employee lived.
     Such payments will be made only during the lifetime of the Employee's
     surviving spouse and will cease upon the death of said spouse.

                                       OR

     OPTION E. The Company will pay solely to an Employee's surviving spouse, in
     equal monthly payments, 32% of the Employee's Final Annual Salary each year
     for each of the first 15 years following the later of the Employee's death
     or the date the Employee would have attained age 62 had the Employee lived.
     Such payments will be made only during the lifetime of the Employee's
     surviving spouse and will cease upon the death of said spouse.

C.   Dependent Child Benefit

     Provided the conditions specified in Article 7, Section C are satisfied,
the Company will pay to a Dependent Child of an Employee who participated in the
Plan, a dependent child benefit of 1/96th of the Employee's Final Annual Salary
during the month of the Survivor's death and monthly thereafter through and
including the month the Dependent Child attains age 21. All such payments are
limited to persons who qualify as a Dependent Child and no other person shall
receive any dependent child benefit.


<PAGE>   12

D.   Assumption of Liability for Benefits

     The Company will assume Primark Corporation's obligations with respect to
each person who was covered by the Primark Corporation Supplemental Death
Benefit and Retirement Income Plan and who is a Director or Employee of the
Company immediately after the effective date of the spin-off of the Company from
Primark Corporation except for the obligation to the person who, immediately
before the spin-off, was the Chief Executive Officer of Primark Corporation.

                                    ARTICLE 7

                        CONDITIONS FOR BENEFITS BENEFITS

A. Pre-Retirement Death Benefit

     Subject to the following conditions, the pre-retirement death benefit
provided in Article 6, Section A shall be paid to an Employee's or Director's
surviving spouse.

CONDITIONS

     1.   The Employee shall have been in the continuous employ of the Company
          or a Subsidiary from the date of participation in the Plan until the
          time of the Employee's death. With respect to Directors, the Director
          shall have served continuously on the Board from the date of
          participation in the Plan until the time of the Director's death; and

     2.   The Employee shall have died while in the employ of the Company or a
          Subsidiary and prior to the Employee's actual retirement from the
          Company or a Subsidiary. With respect to Directors, the Director shall
          have died while holding office.

B.   Post-Retirement Benefit

     Subject to the following conditions, the post-retirement death benefit
provided in Article 6, Section B1 or B2 shall be paid to an Employee or Director
or the respective surviving Spouse.


<PAGE>   13

     CONDITIONS

     1.   The Employee shall have been in the continuous employ of the Company
          or a Subsidiary from the date of participation in the Plan until the
          time of the Employee's retirement. With respect to Directors, the
          Director shall have served continuously on the Board from the date of
          participation in the Plan until the Director attains age 65, unless
          otherwise approved by the Committee; and

     2.   The Employee shall have retired from the Company or a Subsidiary in
          accordance with the terms of the MichCon Retirement Plan. With respect
          to Directors, the Director shall have ceased to hold office as a
          Director, otherwise than by death.

C.   Dependent Child Benefit

     Subject to the following conditions, the dependent child benefit provided
in Article 6, Section C shall be paid to any person who qualifies as a Dependent
Child.

     CONDITIONS

     1.   The Employee shall have been in the continuous employ of the Company
          or a Subsidiary from the date of participation in the Plan until the
          time of the Employee's death; and

     2.   The Employee shall have died while in the employ of the Company or a
          Subsidiary and prior to the Employee's actual retirement from the
          Company or a Subsidiary; and

     3.   The Employee's spouse (if any) shall have died; and

     4.   A Dependent Child survives.

D.   Continued Services Required

     Except as provided in this Section, all rights to benefits under this Plan
shall terminate upon termination of the Employee's employment with the Company
or a Subsidiary for any reason other than the Employee's death or retirement in
accordance with the terms of the MichCon Retirement Plan. With respect to
Directors, except as provided in this Section, all rights to benefits under this
Plan shall terminate if the Director ceases to hold office as a Director before
the Director attains age 65, unless otherwise approved by the Committee.


<PAGE>   14

     Notwithstanding any other provision of this Plan, if (1) a Change in
Control occurs, (2) the Employee was either admitted to participation in the
Plan on or before July 1, 1988, or the Change in Control occurs more than 12
months (or such shorter period as approved by the Committee) after the Employee
was admitted to participation in the Plan, and (3) within 60 months after the
Change in Control occurs, the employment of the Employee is terminated (i) by
the Company other than for Cause or (ii) by the Employee for Good Reason, then
all rights to benefits under this Plan shall continue as if such termination of
employment had not occurred. A pre-retirement death benefit shall be available
if such person dies prior to attaining age 62, and a post-retirement benefit
shall be available when such person attains age 62.

     Notwithstanding any other provision of this Plan, if (1) a Change in
Control occurs, (2) the Director was either admitted to participation in the
Plan on or before July 1, 1988, or the Change in Control occurs more than 12
months (or such shorter period as approved by the Committee) after the Director
was admitted to participation in the Plan, and (3) as part of or within 60
months after the Change in Control, the Director ceases to hold office otherwise
than (i) removal by the shareholders for Cause, or (ii) resignation by the
Director, then all rights to benefits shall continue as if the Director had
continued to hold office. A pre-retirement death benefit shall be available if
such Director dies prior to attaining age 65, and a post-retirement benefit
shall be available when such Director attains age 65.

     Notwithstanding any other provision of this Plan, if an Employee is
admitted to participation in the Plan, and has reached age 55, and thereafter,
the employment of the Employee is terminated prior to retirement other than for
Cause, then all rights to benefits under this Plan accrued as of the later of
December 31, 1993 or on December 31 of the year the employee reaches age 55
shall continue as if such termination of employment had not occurred. A
pre-retirement death benefit shall be available if such person dies prior to
attaining age 62, and a post-retirement benefit shall be available when such
person attains age 62.



<PAGE>   15
                                   ARTICLE 8

                                 UNFUNDED PLAN

     This Plan shall not be a funded plan. Any insurance Policy or other asset
acquired or held by the Company in connection with this Plan shall not be deemed
to be held by the Company in trust for any person, or to be security for the
performance of any obligations of the Company, but shall be and remain a general
asset of the Company. No person shall have any property interest in any specific
assets of the Company. Any rights acquired pursuant to the Plan shall be those
of an unsecured creditor. The obligation to make payments under this Plan shall
be and remain an unsecured, unfunded general obligation of the Company.

                                    ARTICLE 9

                                   ASSIGNMENT

     No benefit hereunder of any person is assignable or transferable to any
other person nor may such be sold, assigned, conveyed, or otherwise transferred
or hypothecated.

                                   ARTICLE 10

                                 ADMINISTRATION

     This Plan shall be administered by the Committee. The Committee shall have
full authority and responsibility to interpret and administer the terms of the
Plan and may adopt rules and regulations governing the administration of the
Plan.

     The Committee shall be responsible for making recommendations to the Board
with respect to Employees and Directors who are to participate in the Plan. In
discharging this responsibility, the Committee may consult with individual
members of the Board, with the management of the Company or with such other
persons as the Committee may deem appropriate.

     The Board shall determine which Employees and Directors shall participate
in the Plan, based upon the recommendations of the Committee, and the Board's
own consideration of who should participate in the Plan.

<PAGE>   16
     The Committee, in its absolute discretion, may cause benefit payments to
an Employee to commence prior to the Employee attaining age 62 if it deems such
action appropriate to the circumstances.

     The Committee, in its absolute discretion, may provide benefits to a
Director even if the Director fails to hold office until the Director attains
age 65 and may cause benefit payments to such Director to commence prior to the
Director attaining age 65 if it deems such action appropriate to the
circumstances.

     The Committee, in its absolute discretion, may provide benefits to an
Employee or Director even if such person was admitted to participation in the
Plan or the Primark Corporation Supplemental Death Benefit and Retirement Income
Plan within 12 months of a Change in Control.

     Any member of the Committee or of the Board who is being considered for
eligibility or who would be affected by a matter being considered shall not vote
or act on such matter.

                                   ARTICLE 11

                      AMENDMENT, SUSPENSION OR TERMINATION

     MCN's Board of Directors may at any time amend, suspend or terminate the
Plan, or any part thereof, for any purpose; provided, however, that no such
amendment, suspension or termination shall affect any agreement between an
Employee or Director and MCN without the written consent of the Employee or
Director.

                                   ARTICLE 12

                            Legal Fees and Expenses

     MCN shall pay all legal fees and expenses that an Employee or Director
admitted to participation in the Plan, or such Employee's or Director's spouse
or Dependent Child may incur as a result of MCN contesting the validity,
enforceability, or any such person's interpretation of, or determinations under
this Plan; provided, however, MCN shall not be required to pay any fees or
expenses of any such person unsuccessfully seeking to obtain benefits following
a Change in Control based upon termination of employment or removal from Office
for Cause.


<PAGE>   17




                                   ARTICLE 13

                            No Employment Rights and
                      Not a Contract to Continue in Office

     Nothing contained in the Plan and no actions taken pursuant to the
provisions of the Plan shall be construed as a contract of employment between
the Company or a Subsidiary and an Employee, or as a right of any Employee to be
continued in the employment of the Company or a Subsidiary, or as a limitation
of the right of the Company or a Subsidiary to discharge any Employee at any
time, with or without cause, or as a limitation of the right of the Employee to
terminate employment at any time.

     Nothing contained in the Plan and no actions taken pursuant to the
provisions of the Plan shall be construed as a contract for services between the
Company and a Director, or as a right of a Director to continue to serve as a
director, or as a limitation of the right of shareholders to remove a Director
from office, with or without cause, or as a limitation of the right of the
Director to resign from office.

     IN WITNESS WHEREOF, the undersigned officer of the Company has executed
this Plan as of this 1st day of April, 1997.



                                   MICHIGAN CONSOLIDATED GAS COMPANY



                                   By: /s/ Stephen E. Ewing
                                      ------------------------------
                                        Stephen E. Ewing,
                                        President and Chief Executive
                                        Officer

Restated April 1, 1997


<PAGE>   18




                              MCN ENERGY GROUP INC.

                         SUPPLEMENTAL DEATH BENEFIT AND

                           RETIREMENT INCOME AGREEMENT

                                    EMPLOYEE


     THIS AGREEMENT is made this        day of)      ,            , between MCN
Energy Group Inc., a Michigan Corporation, (the "Corporation") and          , an
employee of the Corporation (the "Employee").


                                   WITNESSETH

     WHEREAS, the Employee has agreed to serve as an officer of the Corporation
and the Corporation desires to encourage the Employee to continue to perform his
or her duties in a capable and efficient manner.

     NOW, THEREFORE, in consideration of the foregoing and the benefits to be
derived hereunder, the Corporation and Employee agree as follows:
     The Employee shall receive the benefits of an Employee under the MichCon
Supplemental Death Benefit and Retirement Income Plan ("Plan") as in effect on
this date subject to all the terms and conditions as specified in the Plan. The
Plan and all its provisions are hereby incorporated by reference. The benefits
under this Agreement are in lieu of those otherwise payable by MichCon.


<PAGE>   19




IN WITNESS WHEREOF, the undersigned officer of the Corporation has executed this
agreement an behalf of the Corporation and the Employee has executed this
agreement on the date first above written:



                                    MCN ENERGY GROUP INC.

                                    By:
                                       -----------------------------------

                                    Its: Secretary
                                        ----------------------------------



                                    EMPLOYEE


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

<PAGE>   20




                              MCN ENERGY GROUP INC.

                         SUPPLEMENTAL DEATH BENEFIT AND

                           RETIREMENT INCOME AGREEMENT

                              OPTION ELECTION FORM

                                    EMPLOYEE


Name                                               Soc. Sec. No.
Retirement Date                                    I. D. No.
Name of Spouse                                     Soc. Sec. No.

I hereby elect to receive the following post-retirement benefit under my
Supplemental Death Benefit and Retirement Agreement with MCN Energy Group Inc.
which is subject to all the terms and conditions specified in the MichCon
Supplemental Death Benefit and Retirement Income Plan ("Plan"). The Plan and all
its provisions are hereby incorporated by reference.

                              Option A

                              Option B

                              Option C

                              Option D

                              Option E

I understand that once having retired, I may not change this election.



---------------------------                -----------------------------------
  Date                                     Employee


---------------------------                -----------------------------------
  Date                                     Witness


<PAGE>   21




                             MCN ENERGY GROUP INC.

                         SUPPLEMENTAL DEATH BENEFIT AND

                           RETIREMENT INCOME AGREEMENT

                                    DIRECTOR

     THIS AGREEMENT is made this     day of        , 19     , between MCN Energy
Group Inc., a Michigan Corporation, (the "Corporation") and                   ,
a non-employee director of the Corporation (the "Director").



                                   WITNESSETH



     WHEREAS, the Director has agreed to serve On the Board of Directors of the
Corporation and the Corporation desires to encourage the Director to continue to
perform his or her duties in a capable and efficient manner.

     NOW, THEREFORE, in consideration of the foregoing and the benefits to be
derived hereunder, the Corporation and Director agree as follows:

     The Director shall receive the benefits of a Director under the MichCon
Supplemental Death Benefit and Retirement Income Plan ("Plan") as in effect as
of January 4, 1989 subject to all the terms and conditions as specified in the
Plan. The Plan and all its provisions are hereby


<PAGE>   22




incorporated by reference. The benefits under this Agreement are in lieu of
those otherwise payable by MichCon.

     IN WITNESS WHEREOF, the undersigned officer of the Corporation has executed
this agreement on behalf of the Corporation and the Director has executed this
agreement on the date first above written:



                                        MCN ENERGY GROUP INC.

                                        By:
                                           --------------------------

                                        Its: Secretary
                                             ------------------------



                                        DIRECTOR



                                        -----------------------------
                                        Director


<PAGE>   23


                              MCN ENERGY GROUP INC.

                         SUPPLEMENTAL DEATH BENEFIT AND

                           RETIREMENT INCOME AGREEMENT

                              OPTION ELECTION FORM

                                    DIRECTOR


Name                                              Soc. Sec. No.
Last Date to Hold Office
Name of Spouse                                    Soc. Sec. No.

I hereby elect to receive the following post-retirement benefit under the
MichCon Supplemental Death Benefit and Retirement Income Plan ("Plan"), subject
to all the terms and conditions specified in the Plan. The Plan and all its
provisions are hereby incorporated by reference.

                                    Option A

                                    Option C


I understand that once having ceased to serve on the Board of Directors of MCN
Energy Group Inc., I may not change this election.



------------------------------            ----------------------------------
   Date                                        Director

------------------------------                 --------------------------------
   Date                                        Witness


<PAGE>   24


                        MICHIGAN CONSOLIDATED GAS COMPANY

                         SUPPLEMENTAL DEATH BENEFIT AND

                           RETIREMENT INCOME AGREEMENT

                                    EMPLOYEE

     THIS AGREEMENT is made this      day of                19  , between
Michigan Consolidated Gas Company, a Michigan Corporation, (the "Company") and
                  , an employee of the Company (the "Employee").



                                   WITNESSETH



     WHEREAS, the Employee has agreed to serve as an officer of the Company and
the Company desires to encourage the Employee to continue to perform his or her
duties in a capable and efficient manner.


     NOW, THEREFORE, in consideration of the foregoing and the benefits to be
derived hereunder, the Company and Employee agree as follows:
     The Employee shall receive the benefits of an Employee under the MichCon
Supplemental Death Benefit and Retirement Income Plan ("Plan") as in effect on
this date subject to all the terms and conditions as specified in the Plan.


<PAGE>   25




     IN WITNESS WHEREOF, the undersigned officer of the Company has executed
this agreement on behalf of the Company and the employee has executed this
agreement on the date first above written:


                                  MICHIGAN CONSOLIDATED GAS COMPANY

                                  By:
                                     --------------------------------
                                          Stephen E. Ewing


                                  Its: President and Chief Executive
                                          Officer



                                  EMPLOYEE


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

<PAGE>   26



                        MICHIGAN CONSOLIDATED GAS COMPANY

                         SUPPLEMENTAL DEATH BENEFIT AND

                           RETIREMENT INCOME AGREEMENT

                              OPTION ELECTION FORM

                                    EMPLOYEE

Name                                     Soc. Sec. No.
Retirement Date                          I. D. No.
Name of Spouse                           Soc. Sec. No.

I hereby elect to receive the following post-retirement benefit under my
Supplemental Death Benefit and Retirement Agreement with the Company which is
subject to all the terms and conditions specified in the MichCon Supplemental
Death Benefit and Retirement Income Plan ("Plan"). The Plan and all its
provisions are hereby incorporated by reference.

                                    Option A

                                    Option B

                                    Option C

                                    Option D

                                    Option E

I understand that once having retired, I may not change this election.


-------------------------------              -----------------------------------
     Date                                    Employee


-------------------------------              -----------------------------------
     Date                                    Witness