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                                                                   EXHIBIT 10.15





                                     MICHCON
                       INVESTMENT AND STOCK OWNERSHIP PLAN
           (AS AMENDED AND RESTATED EFFECTIVE AS OF JANUARY 1, 1998)




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                                     MICHCON
                       INVESTMENT AND STOCK OWNERSHIP PLAN
           (As Amended and Restated Effective as of January 1, 1998)


                               TABLE OF CONTENTS

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ARTICLE I  The Plan......................................................................................... 1

   1.1   Establishment and Amendment of the Plan............................................................ 1
   1.2   Applicability of the Plan.......................................................................... 1
   1.3   Purpose and Type of Plan........................................................................... 1

ARTICLE II  Definitions..................................................................................... 1

   2.1   Actual Deferral Percentage......................................................................... 2
   2.2   Affiliated Company................................................................................. 2
   2.3   Anniversary Date................................................................................... 2
   2.4   Annual Addition.................................................................................... 2
   2.5   Average Actual Deferral Percentage................................................................. 2
   2.6   Break in Service Year.............................................................................. 2
   2.7   Code............................................................................................... 2
   2.8   Company............................................................................................ 2
   2.9   Compensation....................................................................................... 2
   2.10  Detroit Local Participants......................................................................... 3
   2.11  Disability Retirement Date......................................................................... 3
   2.12  Elective Deferrals................................................................................. 3
   2.13  Eligible Employee.................................................................................. 3
   2.14  Employee........................................................................................... 3
   2.15  Employee Post-1986 Voluntary Deduction Account..................................................... 4
   2.16  Employee Pre-1987 Voluntary Deduction Account...................................................... 4
   2.17  Employee Salary Reduction Account.................................................................. 4
   2.18  Employer........................................................................................... 4
   2.19  Employer Salary Reduction Account.................................................................. 4
   2.20  Employer Voluntary Deduction Account............................................................... 4
   2.21  ERISA.............................................................................................. 4
   2.22  ESOP............................................................................................... 4
   2.23  ESOP Account....................................................................................... 4
   2.24  Excess Contributions............................................................................... 4
   2.25  Excess Deferrals................................................................................... 4
   2.26  Greater Michigan Local Participants................................................................ 4
   2.27  Highly Compensated Employee.........................................................................5
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   2.28  Hour of Employment................................................................................. 5
   2.29  Investment Plan Account............................................................................ 5
   2.30  MCN Stock.......................................................................................... 5
   2.31  Military Service................................................................................... 5
   2.32  Nonhighly Compensated Employee..................................................................... 5
   2.33  Normal Retirement Date............................................................................. 5
   2.34  Participant........................................................................................ 5
   2.35  Plan............................................................................................... 5
   2.36  Plan Account....................................................................................... 5
   2.37  Plan Year.......................................................................................... 6
   2.38  Regulations........................................................................................ 6
   2.39  Salary Reduction................................................................................... 6
   2.40  Salary Reduction Account........................................................................... 6
   2.41  Savings Plan....................................................................................... 6
   2.42  Suspense Account................................................................................... 6
   2.43  Trust.............................................................................................. 6
   2.44  Trust Agreement.................................................................................... 6
   2.45  Trustee............................................................................................ 6
   2.46  Valuation Date..................................................................................... 6
   2.47  Vesting Requirement................................................................................ 6
   2.48  Voluntary Deduction................................................................................ 6
   2.49  Voluntary Deduction Account........................................................................ 6
   2.50  Years of Service................................................................................... 6

ARTICLE III   Participation and Service..................................................................... 6


   3.1   Eligibility Requirements........................................................................... 6
   3.2   Eligibility Upon Merger or Reemployment............................................................ 7 
   3.3   Collective Bargaining Agency....................................................................... 8
   3.4   Applications....................................................................................... 8 
   3.5   Years of Service................................................................................... 8 
   3.6   Break in Service Year.............................................................................. 9
   3.7   Hours of Employment................................................................................ 9
   3.8   Employment by Related Entities..................................................................... 10      
   3.9   Leased Employees................................................................................... 11

ARTICLE IV   Contributions.................................................................................. 11 
                                                                                                                 

   4.1   Employee Contributions............................................................................. 11 
   4.2   Employer Investment Plan Contributions............................................................. 12
   4.3   Employer ESOP Contributions........................................................................ 14
   4.4   Additional Employer Contributions.................................................................. 15
   4.5   Rollover Contributions............................................................................. 15
   4.6   Transfers from the Savings Plan.................................................................... 16 
   4.7   Limitations on Salary Reduction Contributions...................................................... 17 
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   4.8    Distribution of Excess Deferrals...................................................................18
   4.9    Distribution or Recharacterization of Excess Contributions.........................................19
   4.10   Statutory (Code Section 415) Limitations on Allocations to Accounts................................20

ARTICLE V  Vesting in Accounts...............................................................................22
                                                                                                             

   5.1    Employee Salary Reduction Accounts,
           Employee Post-1986 Voluntary Deduction Account,
           and Employee Pre-1987 Voluntary Deduction Account.................................................22
   5.2    Employer Salary Reduction Account, Employer Voluntary
           Deduction Account, and ESOP Account...............................................................22

ARTICLE VI   Investment Provisions...........................................................................23
                                                                                                             

   6.1    Investment of Contributions........................................................................23
   6.2    Change of Investment Direction.....................................................................23
   6.3    Transfers Between Investment Funds.................................................................23

ARTICLE VII  Investment Funds................................................................................24

   7.1    Investment Funds...................................................................................24
   7.2    Management of Investment Funds.....................................................................24
   7.3    Voting of MCN Stock................................................................................24
   7.4    Tender Offers......................................................................................25
   7.5    Named Fiduciary Status.............................................................................26
   7.6    Expenses of Funds..................................................................................26

ARTICLE VIII   Accounts and Records of the Plan..............................................................26
                                                                                                             

   8.1    Company to Maintain Accounts.......................................................................26
   8.2    Plan Accounting....................................................................................27
   8.3    Valuation of Funds.................................................................................27
   8.4    Valuation of Investment Plan Account...............................................................27
   8.5    Valuation of ESOP Account..........................................................................27
   8.6    Valuation of Plan Account..........................................................................27
   8.7    Company to Furnish Annual Statements of Value of Plan..............................................27
   8.8    Trust Agreement....................................................................................27

ARTICLE IX   Distributions, Withdrawals and Loans............................................................28


   9.1    Distribution Upon Termination of Employment
           Entitling Participant to Value of Plan Account....................................................28
   9.2    Distribution Upon Termination of Employment Under
           Circumstances Resulting in Forfeiture of Employer Contributions...................................28
   9.3    Certain Distributions from Participant Accounts....................................................28

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   9.4    In-Service Withdrawals -- General..................................................................29
   9.5    Withdrawal of Voluntary Deduction Contributions....................................................29
   9.6    Hardship Withdrawal of Salary Reduction Contributions..............................................29
   9.7    Time of Distributions..............................................................................31
   9.8    Distributions of Stock.............................................................................33
   9.9    Distributions from Fixed Income Fund...............................................................33
   9.10   Loans..............................................................................................35
   9.11   Definition of Employee Contributions and Employer Contributions....................................37
   9.12   Spousal Consent to Payment.........................................................................37
   9.13   Distributions Pursuant to a Qualified Domestic Relations Order.....................................37
   9.14   Direct Rollovers of Eligible Distributions.........................................................37
   9.15   Special Distribution Events........................................................................38

ARTICLE X   Administration...................................................................................39
                                                                                                             

   10.1   Plan Administration and Interpretation.............................................................39
   10.2   Notice to Employees................................................................................40
   10.3   Notices to Employers...............................................................................40
   10.4   Participants' Acceptance of the Provisions of the Plan.............................................40
   10.5   Audit of Plan Records..............................................................................40
   10.6   Claims Procedure...................................................................................40
   10.7   Effect of a Mistake................................................................................41

ARTICLE XI   Amendment and Termination.......................................................................41
                                                                                                             

   11.1   Amendment..........................................................................................41
   11.2   Withdrawal.........................................................................................41
   11.3   Termination........................................................................................41
   11.4   Allocation of Funds Between Employers..............................................................42
   11.5   Trust to be Applied Exclusively for Participants and Their Beneficiaries...........................42

ARTICLE XII   Participation by Affiliated Companies..........................................................42
                                                                                                             

   12.1   Adoption of the Plan...............................................................................42
   12.2   Withdrawal from the Plan...........................................................................42
   12.3   Company as Agent for Employers.....................................................................42

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ARTICLE XIII  Special Provisions Relating to the ESOP........................................................43    
                                                                                                            
   13.1   Establishment of ESOP..............................................................................43
   13.2   ESOP Account.......................................................................................43
   13.3   Discrimination Testing.............................................................................43
   13.4   Loans..............................................................................................43
   13.5   Diversification....................................................................................45
   13.6   Put Option.........................................................................................45
   13.7   Purchase of MCN Stock..............................................................................46

ARTICLE XIV   Miscellaneous..................................................................................46
                                                                                                             

   14.1   Beneficiary Designation............................................................................46
   14.2   Incompetency.......................................................................................47
   14.3   Expenses...........................................................................................47
   14.4   Nonassignability...................................................................................47
   14.5   Employment Noncontractual..........................................................................48
   14.6   Merger or Consolidation with Another Plan..........................................................48
   14.7   Continuance by a Successor.........................................................................48
   14.8   USERRA Rights......................................................................................48
   14.9   Construction.......................................................................................48

ARTICLE XV  Redesignation of ESOP and Distribution of Dividends..............................................48
                                                                                                             

   15.1   Redesignation of ESOP Portion of Plan..............................................................49
   15.2   Allocation of Investment Plan Account Balances to ESOP Portion of Plan.............................49
   15.3   Distribution of Dividends on MCN Stock.............................................................49

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                                     MICHCON
                       INVESTMENT AND STOCK OWNERSHIP PLAN
            (As Amended and Restated Effective as of January 1, 1998)


                               ARTICLE I THE PLAN

         1.1  Establishment and Amendment of the Plan. Michigan Consolidated Gas
Company, which is also known as MichCon (hereinafter referred to as the
"Company"), presently maintains an investment and stock ownership plan for the
benefit of its Eligible Employees and the Eligible Employees of its
participating Affiliated Companies. The plan was last restated effective as of
April 1, 1989, and was amended from time to time thereafter.

         The Company previously established the MichCon Employee Stock Ownership
Plan for Union Employees ("ESOP") and incorporated the ESOP into the Michigan
Consolidated Gas Company Union Employee's Investment Plan to form the MichCon
Investment and Stock Ownership Plan.

The plan is hereby further amended and completely restated as set forth herein
effective as of January 1, 1998, except as otherwise provided herein or required
by law (for instance, certain provisions herein are legally required to be
effective as of January 1, 1997, and are therefore effective as of such date),
and shall continue to be known as the "MichCon Investment and Stock Ownership
Plan" (the "Plan"). The ESOP provisions of the Plan became effective as of April
1, 1989.

         1.2  Applicability of the Plan. Except as otherwise specified herein or
required by law, the provisions of the Plan as amended and restated herein
effective as of January 1, 1998, shall be applicable only with respect to
Eligible Employees of an Employer in current employment on or after January 1,
1998, and their beneficiaries.

Any person who was covered under the Plan as in effect prior to January 1, 1998,
and whose employment terminated under the Plan prior to January 1, 1998, shall
continue to have his rights to receive benefits determined under the provisions
of the Plan in effect when his employment relationship so terminated, subject to
legally required changes prior to January 1, 1998, as described herein.

         1.3  Purpose and Type of Plan. The purpose of the Plan is to provide a
convenient way for Participants to save on a regular and long-term basis for
their retirement income needs; to recognize the contribution made to the
Employer's successful operation by its employees and to reward such contribution
for those employees who qualify as participants under the terms of the Plan; and
to facilitate ownership of MCN Stock by participating Eligible Employees.

The non-ESOP portion of the Plan is intended to qualify as a profit-sharing plan
and the ESOP portion of the Plan is intended to qualify as a stock bonus and an
employee stock ownership plan for purposes of Code sections 401(a), 402, 412,
417, 4975, and related provisions.


                             ARTICLE II DEFINITIONS

 

                                        1

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         Whenever used in the Plan, the following words and phrases shall have
the respective meanings stated below unless a different meaning is plainly
required by the context.

         2.1  "Actual Deferral Percentage" means the ratio (expressed as a
percentage) of (A) the (a) Elective Deferrals of an Employee who is eligible to
participate in the Plan for a Plan Year, to (b) the Compensation of that
Employee for such Plan Year.

         2.2  "Affiliated Company" means--

              (a)  any corporation other than the Company, i.e., either a 
subsidiary corporation or an affiliated or associated corporation of the
Company, which together with the Company is a member of a "controlled group" of
corporations (as defined in Code section 414(b));

              (b)  any organization which together with the Company is under 
"common control" (as defined in Code section 414(c));

              (c)  any organization which together with the Company is an 
"affiliated service group" (as defined in Code section 414(m)); or

              (d)  any other entity required to be aggregated with the Company 
pursuant to Regulations under Code section 414(o).

         2.3  "Anniversary Date" means with respect to each Employee, the 
anniversary each year of the Employee's first Hour of Employment. If an Employee
whose employment was terminated is reemployed but prior to his reemployment he
incurs a Break in Service Year or following his reemployment he incurs a Break
in Service Year before completing a Year of Service, his Anniversary Date shall
be based upon his first Hour of Employment coincident with or next following his
date of reemployment; otherwise, his Anniversary Date shall not be changed..

         2.4  "Annual Addition" means the amount allocated to a Participant's 
account as such term is defined in section 4.10(a).

         2.5  "Average Actual Deferral Percentage" means the average (expressed 
as a percentage) of the Actual Deferral Percentages of the Employees in a group
who are eligible to participate in the Plan for a Plan Year.

         2.6  "Break in Service Year" means a 12-month period described in
section 3.6.

         2.7  "Code" means the Internal Revenue Code of 1986, as amended.

         2.8  "Company" means Michigan Consolidated Gas Company.

         2.9  "Compensation" means a Participant's pay, determined as follows:

              (a)  For all purposes of the Plan, except as otherwise specified 
in (b) or (c) below or required by the context, Compensation means the regular
basic salary or wage paid (plus, effective July 1, 1998, shift differential) to
an Employee by the Employer before any 


                                       2


<PAGE>   9

payroll deduction for taxes or any other purpose, and before any Salary
Reduction contribution or cafeteria plan election, but excluding merit,
incentive and other similar payments made in the form of a lump sum, bonuses,
awards, shift differentials (prior to July 1, 1998), severance payments,
differential payments made by reason of the Employee's entry into Military
Service, all amounts paid for work in excess of 40 hours in any one week, all
overtime or other premium paid for work in excess of a maximum number of hours
in any one day, for work on holidays or for any other reason, payments for
so-called fringe benefits such as Employer contributions to this Plan or any
pension or retirement plan, increased wages or salary resulting from temporary
promotion, upgrading or transfer, of whatever duration, to a higher paid job or
classification, and any other premium, auxiliary, or special pay of any sort
whatsoever.

              (b)  For purposes of satisfying the limits on contributions 
described in section 4.7 (ADP test) and applying the limits of section 415 of
the Code as described in section 4.10, Compensation shall mean "compensation" as
defined in Treas. Regulation Section 1.415-2(d) or any successor regulation.

              (c) For purposes of determining whether an individual is a Highly 
Compensated Employee, Compensation means an Employee's Compensation as defined
in subsection (b) above but without regard to Code sections 125, 402(a)(8), and
402(h)(1)(B) (i.e., with the addition of elective deferrals pursuant to a
cafeteria plan, a cash-or-deferred arrangement, or a simplified employee pension
during years in which such items are excluded under subsection (b)).

              (d) In accordance with Code Section 401(a)(17), the Compensation 
of each Employee that may be taken into account under the Plan shall not exceed
the first $150,000 of an Employee's Compensation (as adjusted pursuant to Code
section 401(a)(17)).

         2.10 "Detroit Local Participants" means Participants represented by (i)
Local #80 and Local #80 (P. T. & S.), Service Employees International Union and
(ii) Local #799C (P.T.& S.), International Chemical Workers Union Council,
United Food and Commercial Workers.

         2.11 "Disability Retirement Date" means the date a Participant (i)
becomes eligible to receive benefits under a long-term disability plan
maintained by the Employer, or (ii) is determined by the Company to be totally
and permanently disabled. In determining whether a Participant is totally and
permanently disabled, the Company may, in its discretion, rely on the opinion of
a physician selected by the Company to assist it in making such a determination.

         2.12 "Elective Deferrals" means Salary Reduction contributions under
section 4.1(a) and contributions under other plans maintained by the Company or
an Affiliated Company that constitute elective deferrals within the meaning of
Code section 402(g)(3).

         2.13 "Eligible Employee" means an Employee of an Employer whose terms
and conditions of employment are covered by an agreement with a collective
bargaining agent which agreement permits participation in this Plan.

         2.14 "Employee" means an individual who is an employee of the Company
or an Affiliated Company (including, for certain purposes described in Section
3.9, a "leased employee" as described in Section 3.9), but shall not include an
individual who enters into a 


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formal or informal independent contractor agreement with the Company or is 
otherwise treated as an independent contractor under the payroll practices of 
the Company.

         2.15 "Employee Post-1986 Voluntary Deduction Account" means an
Employee's Voluntary Deduction contributions after December 31, 1986, and
investment gains and losses therefrom.

         2.16 "Employee Pre-1987 Voluntary Deduction Account" means an
Employee's Voluntary Deduction contributions before January 1, 1987, and
investment gains and losses therefrom.

         2.17 "Employee Salary Reduction Account" means an Employee's Salary
Reduction contributions, and investment gains and losses therefrom.

         2.18 "Employer" means the Company and any Affiliated Company which has
adopted the Plan with the consent of the Company and in the manner prescribed in
section 12.1 and any successor corporation which shall adopt the Plan pursuant
to section 14.7. If any such corporation shall withdraw from participation in
the Plan in accordance with section 12.2, the term Employer shall not thereafter
include such corporation.

         2.19 "Employer Salary Reduction Account" means the Employer
contributions to the Salary Reduction Account of an Employee pursuant to section
4.2, and investment gains and losses therefrom.

         2.20 "Employer Voluntary Deduction Account" means the Employer
contributions to the Voluntary Deduction Account of an Employee pursuant to
section 4.2, and investment gains and losses therefrom.

         2.21 "ERISA" means the Employee Retirement Income Security Act of 1974,
as amended.

         2.22 "ESOP" means the employee stock ownership plan established
pursuant to section 13.1, as modified by Article XV.

         2.23 "ESOP Account" means the account established and maintained on
behalf of each Participant in accordance with sections 8.1(c) and (d) and 13.2.

         2.24 "Excess Contributions" means the amount described in section
4.9(a).

         2.25 "Excess Deferrals" means the portion of Elective Deferrals for a
calendar year, if any, described in section 4.8.

         2.26 "Greater Michigan Local Participants" means Participants who are
represented by (i) Local #799C Northern, International Chemical Workers Union
Council, United Food and Commercial Workers (ii) Local #70C, International
Chemical Workers Union Council, United Food and Commercial Workers and (iii)
Local #132C, International Chemical Workers Union Council, United Food and
Commercial Workers.


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         2.27 "Highly Compensated Employee" with respect to any Plan Year
beginning on or after January 1, 1997, shall include highly compensated active
employees and highly compensated former employees. A highly compensated active
employee includes any Employee who performs service for an Employer during the
determination year and who, during the look-back year received Compensation from
the Employer in excess of $80,000 (as adjusted pursuant to Code Section 415(d)),
or who was a 5-percent owner at any time during the determination year or the
look-back year. For this purpose, the determination year shall be the Plan Year.
The look-back year shall be the twelve-month period immediately preceding the
determination year.

         A highly compensated former employee includes any Employee who
separated from service (or was deemed to have separated) prior to the
determination year, performed no service for the Employer during the
determination year, and was a highly compensated active employee for either the
separation year or any determination year ending on or after the employee's 55th
birthday.

         The determination of who is a Highly Compensated Employee will be made
in accordance with Section 414(q) of the Code and the regulations thereunder.

         2.28 "Hour of Employment" means an hour for which an individual
receives credit pursuant to section 3.7.

         2.29 "Investment Plan Account" means the total value of an Employee's
Salary Reduction Account and Voluntary Reduction Account.

         2.30 "MCN Stock" means common stock of MCN Energy Group Inc..

         2.31 "Military Service" means service (a) on active duty, in time of
national or local emergency, in the armed forces of the United States or of any
State thereof, (b) in the armed forces of the United States or of any State
thereof under any compulsory service law, or (c)in the armed forces of the
United States or any of its allies in time of war in which the United States is
engaged.

         2.32 "Nonhighly Compensated Employee" means an Employee of the Employer
who is not a Highly Compensated Employee.

         2.33 "Normal Retirement Date" means the Participant's sixty-fifth
(65th) birthday, if such birthday falls on the first day of the month;
otherwise, the first day of the month next following the month in which such
birthday occurs.

         2.34 "Participant" means an Employee who is participating in the Plan
in accordance with its provisions.

         2.35 "Plan" means MichCon Investment and Stock Ownership Plan and any
amendments thereto or restatements thereof from time to time adopted.

         2.36 "Plan Account" means the total value of an Employee's Investment
Plan Account and ESOP Account.


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         2.37 "Plan Year" means the calendar year.

         2.38 "Regulations" means regulations issued by the Department of Labor
construing Title I of ERISA or by the Internal Revenue Service construing the
Code.

         2.39 "Salary Reduction" means an election by a Participant to have the
Compensation that would otherwise be payable reduced and contributed by the
Employer to the Plan as a regular contribution on behalf of the Participant.

         2.40 "Salary Reduction Account" means an Employee's Salary Reduction
contributions, related Employer matching contributions, and investment gains and
losses therefrom.

         2.41 "Savings Plan" means the MCN ENERGY GROUP Savings and Stock
Ownership Plan (formerly the MichCon Savings and Stock Ownership Plan.

         2.42 "Suspense Account" means the account used to reflect MCN Stock
acquired with loan proceeds pursuant to section 13.4.

         2.43 "Trust" means the Trust created by agreement between the Employers
and the Trustee, as from time to time amended.

         2.44 "Trust Agreement" means the agreement between the Employers and
the Trustee referred to in section 8.8.

         2.45 "Trustee" means the Trustee hereinafter provided for in section
8.8 TRUSTEE UNDER THE TRUST AGREEMENT or any successor Trustee TRUSTEE.

         2.46 "Valuation Date" means each business day on which the New York
Stock Exchange shall be open for business.

         2.47 "Vesting Requirement" means the requirement for vesting described
in section 5.2.

         2.48 "Voluntary Deduction" means an Employee's payroll deduction
contributions other than Salary Reduction contributions.

         2.49 "Voluntary Deduction Account" means an Employee's Voluntary
Deduction contributions, related Employer matching contributions, and investment
gains and losses therefrom.

         2.50 "Years of Service" means year(s) of employment of an Employee by
an Employer or nonparticipating Affiliated Company as such term is defined in
section 3.5.


                      ARTICLE III PARTICIPATION AND SERVICE

         3.1  Eligibility Requirements.


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              (a)  Each individual who was eligible to participate in the Plan 
on December 31, 1997, in accordance with the terms of the Plan in effect on said
date shall continue to be eligible to participate, subject to the provisions of 
this Plan. Each other Employee shall become eligible to participate on the
latest to occur of--

                   (i)   the date he is employed as an Eligible Employee,

                   (ii)  the date on which he completes at least one year of 
eligibility service (as defined in section 3.1(b)), or

                   (iii) the date on which he attains age 21;

                   provided he is employed as an Eligible Employee on such date.

              (b)  For purposes of this Article III, a year of eligibility 
service shall mean the 12-month period beginning on the date of an Employee's
first Hour of Employment, or the 12-month period beginning on an Employee's
Anniversary Date during which he completes at least 1,000 Hours of Employment.

        3.2   Eligibility Upon Merger or Reemployment.

              (a)  Merger. Any Employee who is a Participant in any plan which 
is merged into this Plan shall become a Participant in this Plan immediately
upon the effective date of the merger. Such an Employee shall be eligible to
actively participate in this Plan in accordance with Section 3.4.

              (b)  Reemployment. In the event an Employee's employment is 
terminated and such individual is later reemployed as an Eligible Employee:

                   (i)   If the re-employed reemployed Eligible Employee had not
met the age and service requirements for participation in the Plan during his
prior period of employment but was re-employed reemployed before incurring a
Break in Service Year, his prior period of employment shall be included for
purposes of determining his eligibility for participation in the Plan.

                   (ii)  If the re-employed reemployed Eligible Employee had not
met the age and service requirements for participation in the Plan during his
prior period of employment and incurred a Break in Service Year, he must meet
the participation requirements of Section 3.1 as if he were a new employee.

                   (iii) If the re-employed reemployed Eligible Employee met the
age and service requirements for participation in the Plan during his prior
period of employment, incurred a Break in Service Year, and, pursuant to the
Break in Service Year rules, his years of eligibility service are disregarded,
he must meet the participation requirements of Section 3.1 as if he were a new
employee.

                   (iv)  If the re-employed reemployed Eligible Employee met the
age and service requirements for participation in the Plan during his prior
period of employment and incurred a Break in Service Year, but pursuant to the
Break in Service Year rules his years of eligibility 


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<PAGE>   14

service are not disregarded, he shall again participate in the Plan on the date
of his reemployment;

                   (v)  If the re-employed reemployed Eligible Employee met the 
age and service requirements for participation in the Plan during his prior
period of employment and did not incur a Break in Service Year, he shall again
participate as of the date of his reemployment or, if later, the date upon which
he would have begun participation if not for the termination and reemployment.

         3.3  Collective Bargaining Agency. If any Employee shall become a 
Participant in the Plan and shall thereafter cease to be represented by a
collective bargaining agency pursuant to a collective bargaining agreement
between his Employer and a collective bargaining agency covered under this Plan,
he shall nevertheless continue to be eligible to actively participate in the
Plan until such time as the terms and conditions of his employment are no longer
governed by such a collective bargaining agreement. If such an Employee becomes
eligible to participate in the Savings Plan or any successor plan, his entire
Plan Account shall be transferred to such plan and the Employee shall no longer
be eligible to participate in this Plan. The Participant's Plan Account shall be
fully vested upon such transfer.

         3.4  Applications. An Employee who is eligible to participate on the 
date the Plan becomes effective with respect to his Employer may become a
Participant by filing a written application with his Employer in the form
prescribed by the Company. Thereafter, an Eligible Employee may become a
Participant by filing a written application with his Employer in the form
prescribed by the Company. Participation in the Plan will commence within a
reasonable time following processing of a Participant's application.

              The Employee's application shall authorize the Employer to deduct 
contributions from the Employee's Eligible Compensation in amounts specified by
the Employee pursuant to Article IV, and to have contributions made as a Salary
Reduction pursuant to Article IV. The application shall evidence the Employee's
acceptance of and agreement to all of the provisions of the Plan.

         3.5  Years of Service. An Employee shall be credited for Years of 
Service for his period of employment with the Employer and each nonparticipating
Affiliated Company, determined as follows:

              (a)  An Employee shall receive credit, for purposes of vesting, 
for all Years of Service. An Employee shall have one "Year of Service" for each
12-month period beginning on the date of the Employee's first Hour of Employment
and on each subsequent Anniversary Date, during which the Employee completes
1,000 or more Hours of Employment.

              (b)  Years of Service shall not be interrupted (i) by any transfer
of employment of an Employee between Affiliated Companies regardless of whether
the Affiliated Company is an Employer hereunder; or (ii) during such period as
an Employee is receiving credit for Hours of Employment under section 3.7.

              (c)  If an Employee is reemployed following a Break in Service
Year, he shall be considered a new Employee for purposes of the Plan, except--



                                       8
<PAGE>   15

                   (i)   If prior to such Break in Service Year he had a vested 
interest in his ESOP Account, Employer Salary Reduction Account, or Employer
Voluntary Deduction Account, Years of Service he had prior to the Break in
Service Year shall be reinstated after such Employee completes a Year of Service
after such Break in Service Year. 

                   (ii) If paragraph (i) is not applicable, and if the 
Employee's number of consecutive Break in Service Years does not equal or exceed
the greater of five or the number of Years of Service he had before incurring a
Break in Service Year, the Years of Service he had prior to such Break in
Service Years shall be reinstated after such Employee completes a Year of
Service after such Break in Service Years.

              (d)  Notwithstanding the foregoing provisions, an Employee's Years
of Service shall exclude any Years of Service completed before an Employee
attains age 18.

         3.6  Break in Service Year. "Break in Service Year" shall mean a 
12-month period beginning on an Employee's Anniversary Date during which the
Employee has not completed more than 500 Hours of Employment (as defined in
section 3.7). Notwithstanding the foregoing, the following periods shall not be
deemed to be Break in Service Years:

              (a)  If a Participant retires on his Disability Retirement Date,
thereafter ceases to be totally and permanently disabled, and returns to the
employ of an Employer, the period between his Disability Retirement Date and the
date as of which he ceases to be totally and permanently disabled.

              (b)  If a Participant commences receiving benefits under a
long-term disability benefit program maintained by an Employer and thereafter
ceases to receive benefits under such program and returns to the employ of the
Employer, the period during which he was receiving benefits under such program.

         If an Employee incurs a Break in Service Year and prior to such Break
in Service Year has not completed five Years of Service, his Years of Service
completed prior to such a Break in Service Year shall be disregarded unless he
completes a Year of Service after such Break in Service Year and before the
total of such Break in Service Year and any ensuing consecutive Break in Service
Years equals the greater of five or the number of his Years of Service (as
defined in section 3.5 but without excluding Years of Service completed prior to
attaining age 18) prior to such Break in Service Year.

         3.7  Hours of Employment. "Hours of Employment" shall mean, for any 
individual performing or who has performed services for one or more Employers or
nonparticipating Affiliated Companies, the sum of the following:

              (a)  All hours for which the individual is directly or indirectly
paid or entitled to payment by an Employer or nonparticipating Affiliated
Company for the performance of duties. These hours shall be credited to the
individual for the computation period or periods in which the duties are
performed.

              (b)  Except as provided in section 3.7(e) below, all hours for
which the individual is directly or indirectly paid or entitled to payment by an
Employer or nonparticipating Affiliated Company for reasons (such as vacation,
holiday, sickness, incapacity, layoff, jury duty, leave of absence, Military
Service, or disability) other than for the performance of duties.


                                       9
<PAGE>   16


These hours shall be credited to the individual for the computation period or
periods in which the period during which no duties are performed occurs,
beginning with the first unit of time to which the payment relates.

              (c)  All hours for which back pay, irrespective of mitigation of
damages, has been awarded, agreed to, or paid by an Employer or nonparticipating
Affiliated Company, with no duplication of credit for hours. These hours shall
be credited to the individual for the computation period or periods to which the
award or agreement pertains rather than the computation period in which the
award, agreement, or payment is made.

              (d)  Except as provided in section 3.7(e) below, eight Hours of
Employment per day for each working day that an individual is absent from work
without pay for an approved leave of absence, voluntary time, sick time,
disciplinary layoff, or Military Service if the individual returns to the employ
of an Employer or nonparticipating Affiliated Company within 90 days after the
end of such period. These hours shall be credited to the individual for the
computation period or periods in which the period during which no duties are
performed occurs, beginning with the first such period.

              (e)  Eight Hours of Employment per day for each working day that 
an individual is absent from work with or without pay because of pregnancy of 
the individual, birth of a child to the individual, placement of a child with 
the individual in connection with the adoption of such child by such individual,
or caring for such child for a period beginning immediately following such birth
or placement. The Company may, in its discretion, request such information from 
the individual as the Company shall deem relevant in order to verify that an 
absence is for the reasons described in this subsection (e). Notwithstanding the
foregoing, no more than 501 Hours of Employment shall be credited under this
subsection (e) on account of any such pregnancy or placement if the individual
does not return to the employ of an Employer or participating Affiliated Company
within 90 days after the end of the period approved for such absence. Hours
credited under this subsection (e) shall be credited to the individual only in
the year in which the absence begins if the crediting is necessary to prevent a
Break in Service Year for such year; or, in any other case, in the immediately
following year; provided, however, that if more than 501 hours are credited
under this subsection (e) on account of any such pregnancy or placement, the
excess over 501 hours shall be credited to the period or periods to which it
relates.

         Hours of Employment credited under this section 3.7 shall comply with
the rules set forth in 29 C.F.R. section 2530.200b-2(b) and (c), which rules are
hereby incorporated by reference.

         Notwithstanding anything herein to the contrary, Hours of Employment
shall be credited hereunder at all times in compliance with the requirements of
the Family and Medical Leave Act.

         3.8  Employment by Related Entities. If an Employee's employer is a
nonparticipating Affiliated Company, any period in which the Employee is
employed by the nonparticipating Affiliated Company (while an Affiliated
Company) shall be taken into account for purposes of satisfying the eligibility
service requirement set forth in section 3.1 and measuring such Employee's Years
of Service to the same extent it would have been had such period of employment
been employment by an Employer.



                                       10
<PAGE>   17

         3.9  Leased Employees. A person who is not an Employee of an Employer 
or nonparticipating Affiliated Company and who performs services for an Employer
or a nonparticipating Affiliated Company pursuant to an agreement between the
Employer or nonparticipating Affiliated Company and a leasing organization shall
be considered a "leased employee" if such person performed the services on a
substantially full-time basis for a year and the services are under the primary
direction and control of the recipient. A person who is considered a "leased
employee" of an Employer or nonparticipating Affiliated Company shall not be
considered an Employee for purposes of participating in this Plan or receiving
any contribution or benefit under this Plan. A leased employee shall be excluded
from this Plan regardless of whether the leased employee participates in any
plan maintained by the leasing organization. However, if a leased employee
participates in the Plan as a result of subsequent employment with an Employer,
his previous service as a leased employee shall be counted in calculating his
Years of Service. Notwithstanding the preceding provisions of this section 3.9,
a leased employee will be included as an Employee for purposes of applying the
requirements described in Code section 414(n)(3) and for purposes of determining
the number and identity of Highly Compensated Employees.

                            ARTICLE IV CONTRIBUTIONS

         4.1  Employee Contributions.

              (a)  Amount of Contributions. Each Participant may make a regular 
contribution to the Plan (not less than 1 percent) up to a percentage of his
Compensation for a pay period in incremental percentages of 1 percent,
determined as follows:

               Group                                    Percentage
               -----                                    ----------

               For Highly Compensated Employees            15%

               For Nonhighly Compensated Employees 
               who are Detroit Local Participants:

                        Prior to April 1, 1998             20%
                        April 1, 1998 and later            17%

               For Nonhighly Compensated Employees 
               who are Greater Michigan Local 
               Participants:

                        Prior to July 1, 1998              20%
                        July 1, 1998 and later             17%

         Contributions will be effected by Voluntary Deductions, Salary
Reductions, or any combination thereof, as elected by the Participant. The
amount of such Voluntary Deductions or Salary Reductions shall be transferred to
the Trustee after each pay period; provided, however, that a Participant's
Salary Reduction contributions shall not exceed 8 percent of the Participant's
Compensation for a pay period (if the Participant was a Highly Compensated
Employee during the immediately preceding Plan Year), or 9 percent of the
Participant's Compensation for a pay period (if the Participant was not a Highly
Compensated Employee 


                                       11
<PAGE>   18


during the immediately preceding Plan Year); and further provided, however, that
Voluntary Deductions and Salary Reductions shall be limited as provided in
sections 4.7 and 4.10.

         Notwithstanding the foregoing, the Company may, in its sole discretion,
(1) reduce the Salary Reduction contributions permitted by a group of
Participants if, in the opinion of the Company, it is advisable to do so in
order to satisfy the requirements of section 4.7 or 4.10; or (2) reduce the
Voluntary Deduction contributions permitted by a group of Participants if, in
the opinion of the Company, it is advisable to do so in order to satisfy the
requirements of section 4.10.

              (b)  Changes in Contributions. The contribution of Voluntary
Deductions and/or Salary Reductions designated by a Participant shall continue
in effect, notwithstanding any change in his Compensation rate, until the
Participant shall change such contribution; provided, however, that such
contribution shall in no event be less than 1 percent, nor more than the limits
of section 4.1(a), in incremental percentages of 1 percent of the Participant's
Compensation for a pay period. A Participant may change his contribution from
time to time by giving directions to his Employer in the form prescribed by the
Company, with such directions to take effect within a reasonable period
following processing.                
              (c)  Voluntary Suspension of Contributions. Any Participant may, 
by giving notice to his Employer in the form and timing prescribed by the
Company, suspend his contribution of Voluntary Deductions and/or Salary
Reductions, either indefinitely or for any specified period provided that in the
event of suspension of both such contributions the suspension shall be for at
least 12 full months. In case of any such suspension of any contributions, the
Employer's contributions on behalf of the Participant shall be automatically
suspended for a like period.

              (d)  Automatic Suspension of Contributions. A Participant's 
contributions of Voluntary Deductions and Salary Reductions and the Employer's
contributions on behalf of the Participant shall be suspended automatically for
any period during which the Participant is absent without pay under any of the
circumstances described in section 3.7(c), (d), or (e), and such an absence
shall not constitute termination of service for purposes of any of the
provisions of Article IX. A Participant may, by giving notice to his Employer in
the form and timing prescribed by the Company, suspend his contribution of
Voluntary Deductions and/or Salary Reductions for any period during which he is
absent from work under any of the circumstances described in section 3.7(b) or
(c) and receiving Compensation at a reduced Compensation rate, in which case the
Employer contributions on behalf of such Participant shall be automatically
suspended for a like period.

         4.2  Employer Investment Plan Contributions. Each Employer shall 
contribute, to the Salary Reduction Account of each of its participating
Employees, an amount equal to 25 percent of the Salary Reduction contribution of
such Participant; provided, however, that Salary Reduction contributions shall
be disregarded to the extent that they exceed an amount determined by
multiplying the applicable contribution percentage shown in the following
schedules by the Participant's Compensation for a pay period:

              (a)  Prior to January 1, 1999, for all Participants except 
Participants described in subsection (b) below: 



                                       12
<PAGE>   19



                                                Contribution
              Years of Service                   Percentage
              ----------------                  ------------

              1 through 3                            2%
              More than 3 through 6                  3%
              More than 6 through 10                 4%
              More than 10 through 23                5%
              More than 23                           6%

              (b)  Prior to January 1, 1999, for (i) all Participants who became
Eligible Employees on or after July 1, 1995, who are Utility I employees
represented by I.C.W.U.C. U.F.C.W. Local 799C (Northern) or (ii) Participants
who became Eligible Employees on or after April 1, 1997 who are service
consumption technicians represented by Local 80 Detroit:

                                                Contribution
              Years of Service                   Percentage 
              ----------------                   ---------- 

              0 through 3                            0%
              More than 3 through 6                  3%
              More than 6 through 10                 4%
              More than 10 through 23                5%
              More than 23                           6%

              (c)  On and after January 1, 1999, for all Participants except
Participants described in subsection (d) below:

                                                Contribution
              Years of Service                   Percentage  
              ----------------                   ----------  
                                                       
              1 through 3                            2%
              More than 3 through 6                  3%
              More than 6 through 9                  4%
              More than 9 through 23                 5%
              More than 23                           6%

              (d)  On and after January 1, 1999, for (i) all Participants who
became Eligible Employees on or after July 1, 1995, who are Utility  I
employees represented by I.C.W.U.C. U.F.C.W. Local 799C (Northern) or (ii)
Participants who became Eligible Employees on or after April 1, 1997 who are
service consumption technicians represented by Local 80:

                                                Contribution
               Years of Service                  Percentage 
               ----------------                  ---------- 

               0 through 3                           0%
               More than 3 through 6                 3%
               More than 6 through 9                 4%
               More than 9 through 23                5%
               More than 23                          6%




                                       13
<PAGE>   20

         In addition, in cases where the Participant's Salary Reduction
contribution is less than the percentage of his Compensation rate allowed in the
above schedule for his Years of Service, the Employer shall contribute to the
Voluntary Deduction Account of such participating Employee an amount equal to 25
percent of the smaller of (1) the Participant's Voluntary Deduction
contribution, or (2) an amount equal to (A) the applicable contribution
percentage, per the above schedule, times the Participant's Compensation for a
pay period, minus (B) the Participant's Salary Reduction contribution. The
maximum Employer matching contributions on behalf of any Participant shall not
be increased until such Participant has provided notice to the Company in the
manner and timing prescribed by the Company.

          4.3 Employer ESOP Contributions.

              (a)  Basic ESOP Contribution. Each Employer shall contribute to 
the ESOP Account of each of its participating Employees each pay period an 
amount equal to the difference, if any, between (i) and (ii) below:

                   (i)   75 percent of the sum of the Salary Reduction and 
Voluntary Deduction contributions of such Participant for such pay period;
provided, however, that Salary Reduction and Voluntary Deduction contributions
shall be disregarded to the extent that they exceed, in the aggregate, an amount
determined by multiplying the applicable contribution percentage in the
schedules set forth in section 4.2 by such Participant Compensation for the pay
period.

                   (ii)  The value of the shares of MCN Stock allocated to the 
ESOP Account of such Participant pursuant to section 13.4(d) for such pay
period. The value of shares allocated under section 13.4(d) shall be the market
value thereof as of the last day of the pay period for which the shares are
allocated, with the market value to be determined by the Company in a
nondiscriminatory manner.

              (b)  Contribution of Principal, Interest, or Other Payments. Each
Employer also shall contribute to the ESOP its proportionate share of any
additional amount necessary to make principal, interest, or other payments
required by the terms of any loan made to the ESOP in accordance with section
13.4. Each Employer's proportionate share shall be equal to the proportion that
its contributions under section 4.3(a) bears to the total contributions under
section 4.3(a). Each Employer also may make additional contributions to make
principal, interest, or other payments in accordance with the terms of any loan
made to the ESOP in accordance with section 13.4.

              (c)  Dividend-Related Contributions. Each Employer also shall
contribute to the ESOP Account of each of its participating Employees such
amounts as may be necessary to acquire for the ESOP Account of such Participant
shares of MCN Stock having a fair market value equal to the amount of any
dividends on shares of MCN Stock allocated to the ESOP Account of such
Participant that were used to repay an ESOP loan in accordance with section
13.4(c). Such contributions shall be made on, or as soon as practicable after,
each date on which dividends on allocated shares of MCN Stock are used to repay
a loan. In no event shall the shares of MCN Stock acquired with contributions
under this subsection (c) be allocated to the ESOP Account of such Participant
later than the last day of the Plan Year during which (but for the use of the
dividend to repay the loan) the dividend giving rise to such contribution would
have been allocated to the ESOP Account of such Participant.



                                       14
<PAGE>   21

              (d)  Longevity Contributions. Within a reasonable time after each
March 1 (April 1 in the case of Greater Michigan Local Participants prior to
1999) of each Plan Year (in each case, the "Measurement Date"), each Employer
shall contribute to the ESOP Account of each of its participating Eligible
Employees on active payroll as of the Measurement Date who has at least 30 Years
of Service as of such Measurement Date:

                   (i)   effective prior to March 1, 1999 for Greater Michigan 
Local Participants, twenty-five (25) shares of MCN Stock

                   (ii)  effective March 1, 1999 for Greater Michigan Local 
Participants and effective March 1, 1998 for Detroit Local Participants, six
hundred dollars ($600) in shares of MCN Stock, as determined by the Company in a
nondiscriminatory manner.

         4.4  Additional Employer Contributions. If a Participant receiving 
payments (based upon 40 or more hours per week) under the terms of any Workers'
Compensation law does not have sufficient compensation to make Salary Reduction
or Voluntary Deduction contributions in an amount equal to the amount of the
Participant's contributions as in effect during the Participant's last period of
active service, then the Participant's Employer shall contribute on behalf of
the Participant such additional amount as would have been contributed by the
Employer under sections 4.2 and 4.3 on behalf of such Participant had the
Participant's contributions been continued at the rate in effect during the
Participant's last period of active service. Additional contributions under this
section 4.4 shall be treated for accounting purposes as if made under section
4.2 or 4.3, as applicable, except such contributions shall not be considered
when computing the Contribution Percentage. Contributions under this Section 4.4
shall be deemed contributions made under Code Section 415(c)(3)(C), and for
purposes of calculations under Section 415, "compensation" shall include the
compensation the Participant would have received if the Participant were paid at
the rate of compensation paid immediately before becoming disabled.

         4.5  Rollover Contributions.

              (a)  From Qualified Plan. If an Employee receives, either before 
or after becoming an Employee an eligible rollover distribution (within the
meaning of Code section 402(c)(4))from an employees' trust described in Code
section 401(a) which is exempt from tax under Code section 501(a) or from a
qualified annuity plan described in Code section 403(a) (other than an
employees' trust or an annuity plan under which the Employee was an Employee
within the meaning of Code section 401(c)(1) at the time contributions were made
on his behalf under such trust or annuity plan), then such Employee may transfer
and deliver to the Company, to be credited to his Employee Salary Reduction
Account as if it were a Salary Reduction contribution, an amount which does not
exceed the amount of such qualified total distribution or eligible rollover
distribution (including any proceeds from the sale of any property received as a
part of such qualified total distribution or eligible rollover distribution)
less, in the case of a qualified total distribution, the amount considered
contributed to such trust or annuity plan by the Employee. Former Employees who
are Participants and who receive an eligible rollover distribution from another
plan sponsored by an Employer may make rollover contributions in accordance with
this section.


                                       15
<PAGE>   22

              (b)  From Individual Retirement Account or Annuity.  If--

                   (i)   an Employee receives, either before or after becoming 
an Employee, a distribution or distributions from an individual retirement
account or individual retirement annuity (within the meaning of Code section
408) or from a retirement bond (within the meaning of Code section 409); and

                   (ii)  no amount in such account, no part of the value of such
annuity, or no part of the value of the proceeds of such bond is attributable to
any source other than an eligible rollover distribution (within the meaning of
Code section 402(c)(4)) from an employees' trust described in Code section
401(a) which is exempt from tax under Code section 501(a) or annuity plan
described in Code section 403(a) (other than an employees' trust or an annuity
plan under which the Employee was an Employee within the meaning of Code section
401(c) at the time contributions were made on his behalf under such trust or
annuity plan) and any earnings on such a qualified total distribution or
eligible rollover distribution;

              then such Employee may transfer and deliver to the Company, to be 
credited to his Salary Reduction Account as if it were a Salary Reduction
contribution, such distribution or distributions.

              (c)  Timing and Substantiation. Any transfer and delivery pursuant
to this section 4.5 shall be delivered by the Employee to the Company and by the
Company to the Trustee on or before the sixtieth day after the day on which the
Employee receives the distribution or on or before such later date as may be
prescribed by law. Any such transfer and delivery must be accompanied by (i) a
statement of the Employee that to the best of his knowledge the amount so
transferred meets the conditions specified in this section 4.5, and (ii) a copy
of such documents as may have been received by the Employee advising him of the
amount and the character of such distribution. Notwithstanding the foregoing,
the Company shall not accept a rollover contribution if, in its judgment, such
acceptance would cause the Plan to violate any provision of the Code or
Regulations.

              (d)  Deemed Contribution for Certain Purposes. A rollover 
contribution pursuant to this section 4.5 shall be deemed to be a contribution
of a Participant for purposes of the value of a Participant's fund account as
provided in section 8.2 and in determining the amount distributable to a
Participant, the provisions of Article IX that are applicable to Salary
Reduction contributions will be used, pursuant to section 9.1, but not for
purposes of determining the amount of the contribution to be made on behalf of a
Participant by his Employer pursuant to section 4.2, 4.3, or 4.4 or calculating
the Annual Addition of such Participant.

              (e)  Deemed Participation for Certain Purposes. If the amount of 
rollover contribution is made by an Employee prior to his becoming a
Participant, such Employee shall, until such time as he becomes a Participant,
be deemed to be a Participant for all purposes of the Plan except for purposes
of any determination of when he becomes a Participant pursuant to section 3.1
and the making of contributions pursuant to section 4.1(a).

         4.6  Transfers from the Savings Plan. If an Employee who previously had
participated in the Savings Plan becomes a Participant in the Plan and the
Participant's plan account in the Savings Plan (including any outstanding loans)
is transferred to the Plan in 


                                       16
<PAGE>   23

accordance with section 3.3 of the Savings Plan, the Plan shall accept such
transfer. Amounts transferred shall be 100 percent vested at all times and shall
be treated for all purposes in the same manner as they were treated under the
Savings Plan; that is:

              (a)  Amounts attributable to Employer salary reduction
contributions under the Savings Plan shall be allocated to the Participant's
Employee Salary Reduction Account;

              (b)  Amounts attributable to voluntary deduction contributions
under the Savings Plan shall be allocated to the Participant's Employee
Voluntary Deduction Account;

              (c)  Amounts attributable to Employer Savings Plan contributions
shall be allocated to the Participant's Employer Salary Reduction Account or
Employer Voluntary Deduction Account, as the case may be; and

              (d)  Amounts transferred from the ESOP Account of the Participant
in the Savings Plan shall be allocated to the Participant's ESOP Account.

         Notwithstanding the foregoing, amounts transferred shall not be used
for purposes of determining the amount of the contribution to be made on behalf
of a Participant by the Employer pursuant to section 4.2, 4.3, or 4.4, or
calculating the Actual Deferral Percentage or Annual Addition of the
Participant.
         
         4.7  Limitations on Salary Reduction Contributions.

              (a)  Dollar Limitation. In no event shall any Employer make Salary
Reduction contributions for any calendar year, with respect to any Participant
in excess of $10,000 (for 1998) (as adjusted by the Secretary of the Treasury to
reflect increases in the cost of living). This limit shall be applied by
aggregating all plans and arrangements maintained by the Company and all
Affiliated Companies that provide for elective deferrals (as defined in Code
section 402(g)).

              (b)  ADP Test. Effective for Plan Years beginning on or after
January 1, 1997, in addition to the limitations set forth elsewhere in this
Plan, one of the following tests must be satisfied for the Plan Year: 

                   (i)   The Average Actual Deferral Percentage for Highly 
Compensated Employees who are eligible to participate for the Plan Year shall
not exceed the Average Actual Deferral Percentage for the immediately preceding
Plan Year for Nonhighly Compensated Employees who were then eligible to
participate multiplied by 1.25; or

                   (ii)  The Average Actual Deferral Percentage for Highly 
Compensated Employees who are eligible to participate for the Plan Year shall
not exceed the Average Actual Deferral Percentage for the immediately preceding
Plan Year for Nonhighly Compensated Employees who were then eligible to
participate multiplied by two, provided that the Average Actual Deferral
Percentage for such Highly Compensated Employees does not exceed the Average
Actual Deferral Percentage for such Nonhighly Compensated Employees by more than
two percentage points or such lesser amount as the Secretary of Treasury shall
prescribe in accordance with Code section 401(m)(9) to prevent the multiple use
of this alternative limitation with respect to any Highly Compensated Employee.
Any such restriction on the multiple use of the alternative limit shall be
implemented pursuant to uniform rules adopted by the Company.



                                       17
<PAGE>   24

              (c)  Determination of Actual Deferral Percentages. For purposes of
the Actual Deferral Percentage test described in this section 4.7--

                   (i)   An Elective Deferral will be taken into account for a 
Plan Year only if it relates to Compensation that either would have been
received by the Eligible Employee in the appropriate Plan Year (but for the
deferral election) or is attributable to services performed by the Eligible
Employee in the Plan Year and would have been received by the Eligible Employee
within 2 1/2 months after the close of the Plan Year (but for the deferral
election);

                   (ii)  An Elective Deferral will be taken into account for a 
Plan Year only if it is allocated to the Eligible Employee as of a date within
that Plan Year. For this purpose, an Elective Deferral is considered allocated
as of a date within a Plan Year if the allocation is not contingent on
participation or performance of services after such date and the Elective
Deferral is actually paid to the Trust no later than 12 months after the Plan
Year to which the contribution relates;

                  (iii)  The Actual Deferral Percentage for an Employee who is 
eligible to participate shall be computed by treating any Excess Deferral (as
defined in section 4.8) as an Elective Deferral, except to the extent provided
by Regulations;

                   (iv)  The Actual Deferral Percentage for any Employee who is 
a participant under two or more section 401(k) plans or arrangements that are
maintained by the Company or an Affiliated Company shall be determined as if all
such Elective Deferrals were made under a single arrangement; provided, however,
that no Elective Deferrals under an employee stock ownership plan (as defined in
Code section 4975(e)(7)) shall be taken into account for purposes of this
section 4.7;

                   (v)   In the event that two or more plans which include 
cash-or-deferred arrangements are considered as one plan for purposes of Code
section 401(a)(4) or 410(b), the cash-or-deferred arrangements included in such
plans shall be treated as one arrangement for purposes of this section 4.7;

                   (vi)  The determination and treatment of the Elective 
Deferrals and Actual Deferral Percentage of any Employee shall satisfy such
other requirements as may be prescribed by the Secretary of Treasury.

         4.8  Distribution of Excess Deferrals. "Excess Deferrals" means excess
deferrals as defined under Code section 402(g). Notwithstanding any other
provision of the Plan, the Excess Deferral, if any, of each Employee with
respect to a calendar year plus any income and minus any loss allocable thereto
shall be distributed no later than April 15 of the following calendar year to
each Employee who claims an Excess Deferral for the preceding calendar year.
Excess Deferrals shall be treated as Annual Additions under the Plan.

         The Employee's claim shall be in writing; shall be submitted to the
Company no later than March 1; shall specify the Employee's Excess Deferral for
the preceding calendar year; and shall be accompanied by the Employee's written
statement that if such amount is not distributed, such Excess Deferral, when
added to amounts deferred under other plans or 


                                       18
<PAGE>   25


arrangements described in Code section 401(k), 408(k), or 403(b), exceeds the
limit imposed on the Employee by Code section 402(g) for the year in which the
deferral occurred.

         Notwithstanding the preceding paragraph, the Employer may notify the
Plan on behalf of the individual of Excess Deferrals to the extent that the
individual has Excess Deferrals for the calendar year calculated by taking into
account only elective deferrals under this Plan and other plans of the Company
and any Affiliated Company.

         The Excess Deferral distributed to an Employee with respect to a
calendar year shall be adjusted for any income or loss thereon for such calendar
year and for the period between the end of such calendar year and the date of
distribution. The income or loss allocable to such calendar year shall be
determined by multiplying the income or loss for such calendar year allocable to
the Employee's Salary Reduction Account by a fraction, the numerator of which is
the Excess Deferral of the Employee for such calendar year and the denominator
of which is the Employee's Salary Reduction Account balance on the last day of
such calendar year. The income or loss allocable to the period between the end
of such calendar year and the date of distribution shall be equal to 10 percent
of the income or loss allocable to the Excess Deferral for the preceding
calendar year multiplied by the number of calendar months that have elapsed from
the end of the preceding calendar year to the date of distribution. A
distribution occurring on or before the fifteenth day of the month shall be
treated as having been made on the last day of the preceding month and a
distribution occurring after such fifteenth day shall be treated as having been
made on the first day of the following month.

         In the event that an Employee's Salary Reduction contributions are
distributed to such Employee under this section 4.8, any Employer contributions
attributable thereto plus any income and minus any loss allocable thereto shall
be forfeited.

         4.9   Distribution or Recharacterization of Excess Contributions.

              (a)  Determination of Excess Contributions. "Excess Contributions"
means, with respect to any Plan Year, the excess of (i) the aggregate amount of
Elective Deferrals actually paid over to the Trust on behalf of Highly
Compensated Employees for such Plan Year, over (ii) the maximum amount of such
Elective Deferrals permitted under the limitations of section 4.7(b), in
accordance with the provisions of Code Section 401(k)(8).

              Excess Contributions shall be returned to the Highly Compensated 
Employees, beginning with that Highly Compensated Employee who has the highest
dollar amount of Elective Deferrals. The Highly Compensated Employee shall
receive the portion of his Employee Deferrals (and income allocable thereto)
which will either enable the Plan to distribute the total Excess Contribution
(and thereby satisfy the ADP limit stated above) or cause such Highly
Compensated Employee's Elective Deferrals to equal the Elective Deferrals of the
Highly Compensated Employee with the next highest amount of Elective Deferrals.
This prior process must then be repeated until the plan has distributed the
total Excess Contributions described above.

              Excess Contributions shall be treated as Annual Additions under 
the Plan.


                                       19
<PAGE>   26

              For purposes of this section 4.9, to the extent permitted by the 
Code, the Excess Contributions shall be reduced by the amount of any Excess
Deferrals included in such Excess Contributions and distributed to the Employee
pursuant to section 4.8.

              (b)  Distribution or Recharacterization. Notwithstanding any other
provision of the Plan, either--

                   (i)   Excess Contributions with respect to a calendar year 
plus any income and minus any loss allocable thereto shall be distributed no
later than the last day of the following calendar year to Employees on whose
behalf such Excess Contributions were made for the preceding calendar year; or

                   (ii)  at the election of the Employee and to the extent 
permitted by the Code, the Excess Contributions shall be treated as distributed
to the Employee and then contributed by the Employee to the Plan as a Voluntary
Deduction contribution.

              (c)  Adjustment for Income and Loss. The Excess Contributions to 
be distributed to an Employee with respect to a calendar year shall be adjusted
for any income or loss thereon for such calendar year and for the period between
the end of such calendar year and the date of distribution. The income or loss
allocable to such calendar year shall be determined by multiplying the income or
loss for such calendar year allocable to the Employee's Salary Reduction Account
by a fraction, the numerator of which is the Excess Contributions for such
calendar year and the denominator of which is the Employee's Salary Reduction
Account balance on the last day of such calendar year. The income or loss
allocable to the period between the end of such calendar year and the date of
distribution shall be equal to 10 percent of the income or loss allocable to the
Excess Contributions for the preceding calendar year multiplied by the number of
calendar months that have elapsed from the end of the preceding calendar year to
the date of distribution. A distribution occurring on or before the fifteenth
day of the month shall be treated as having been made on the last day of the
preceding month and a distribution occurring after such fifteenth day shall be
treated as having been made on the first day of the following month.

              In the event that an Employee's Salary Reduction contributions are
distributed to such Employee under this section 4.9, any Employer contributions
attributable thereto plus any income and minus any loss allocable thereto shall
be forfeited.

         4.10 Statutory (Code Section 415) Limitations on Allocations to 
Accounts. Notwithstanding any other provision of the Plan, contributions under
the Plan shall be subject to the limitations set forth in Code section 415,
which are incorporated herein by reference. For purposes of applying such
limitations to contributions under the Plan, the rules set forth in this section
4.10 shall be applicable.

              (a)  Annual Addition. The term "Annual Addition" means the amount
allocated to a Participant's account during any calendar year that constitutes--

                   (i)   Employer contributions;

                   (ii)  Employee contributions;



                                       20
<PAGE>   27

                   (iii) forfeitures; and

                   (iv)  amounts described in Code Sections 415(l)(2) and
419(A)(d)(3).

              The compensation limitation referred to in Code section 
415(c)(1)(B) shall not apply to--

                         (1)   any contribution for medical benefits (within the
                               meaning of Code section 419A(f)(2)) after
                               separation from service which is otherwise 
                               treated as an Annual Addition, or

                         (2)  any amount otherwise treated as an Annual Addition
                              under Code Section 415(l)(2).

              The Annual Addition for any calendar year before 1987 shall not be
recomputed to treat all Employee contributions as an Annual Addition.

              (b)  Combined-Plan Limits. Prior to January 1, 2000, in the case 
of an individual who was a Participant in the Plan on December 31, 1986, an
amount shall be subtracted from the numerator of the defined contribution
fraction (not exceeding such numerator) as prescribed by the Secretary of
Treasury so that the sum of the defined benefit plan fraction and defined
contribution plan fraction does not exceed 1.0 as of such date.

         Code section 415 shall be applied in such manner as to maximize the
permissible contributions and benefits thereunder and, in determining the
permissible amount of contributions under the Plan, any grandfathering
provisions heretofore or hereafter adopted pursuant to Code section 415 shall be
applicable. For purposes of applying the limitations set forth in Code section
415(e) prior to January 1, 2000, this Plan shall be the primary plan and any
required reductions shall be made from the Michigan Consolidated Gas Company
Retirement Plan for Employees Covered by Collective Bargaining Agreements (or
other applicable defined benefit plan of the Employer).

              (c)  Reduction of Annual Additions.

                   (i)  If the limitations of Code section 415 would be exceeded
as a result of a reasonable error in estimating a Participant's Compensation or
on account of such other limited facts and circumstances as the Commissioner of
Internal Revenue finds justify the application of the rules hereinafter set
forth, the Annual Additions to the Participant's account which exceed the
applicable limitation shall be returned to the Participant to the extent of all
or any portion of any Voluntary Deduction contributions which were made by him
pursuant to Article IV. Any net earnings and gains allocable to such
contributions for the period between the date of such contribution and the date
returned shall also be repaid to the Participant but such return of net earnings
and gains will not be deemed a further reduction of any excess Annual Additions.

                   (ii)  If the Participant made no Voluntary Deduction
contributions or if, after returning all or part of such contributions in
accordance with the previous paragraph, his Annual Additions still exceed the
limitations of Code section 415, then such excess shall be returned to the
Participant to the extent of all or any portion of any Salary Reduction


                                       21
<PAGE>   28


contributions made on behalf of such Participant, together with any net earnings
and gains on such contributions as hereinabove described.

                   (iii) If, after returning all or any portion of Voluntary
Deduction and Salary Reduction contributions of a Participant in accordance with
the preceding paragraphs, his Annual Additions still exceed the limitations of
Code section 415, such portion of the Employer contributions under section 4.2
made on behalf of the Participant as must be removed to meet the limitations
shall be allocated and reallocated to other Participants' Investment Plan
Accounts as contributions by the Employer.

                   (iv)  If, after reallocating all or any portion of Employer
contributions under section 4.2, a Participant's Annual Additions still exceed
the limitation of Code section 415, such portion of the Employer contributions
under section 4.3(a) made on behalf of the Participant and shares of MCN Stock
allocated to his ESOP Account under section 13.4(d) as must be removed to meet
the limitations shall be allocated and reallocated to other Participant's ESOP
Accounts as contributions by the Employer.

                   (v)   If, as a result of the allocation of forfeitures, a
reasonable error in estimating a Participant's Compensation, or under other
limited facts and circumstances which the Commissioner of the Internal Revenue
Service finds justify the availability of the following rules, any amount cannot
be allocated during the Plan Year in accordance with the foregoing procedure
without exceeding the applicable limitations for one or more Participants, any
remaining amount shall be held unallocated in a special suspense account to be
allocated to Participants in the succeeding Plan Year or Plan Years; provided,
however, that (A) no Employer contributions and no Voluntary Deduction
contributions shall be made in such succeeding Plan Year or Plan Years until
such special suspense account is exhausted by allocations and reallocations; (B)
no investment gains (or losses) or other income shall be allocated to the
special suspense account; and (C) the amounts in the special suspense account
shall be allocated as soon as possible without violating the limitations of this
section 4.10. 


                         ARTICLE V VESTING IN ACCOUNTS

         5.1  Employee Salary Reduction Accounts, Employee Post-1986 Voluntary 
Deduction Account, and Employee Pre-1987 Voluntary Deduction Account. The
Employee Salary Reduction Account, the Employee Post-1986 Voluntary Deduction
Account, and the Employee Pre-1987 Voluntary Deduction Account of each
Participant shall be fully vested and nonforfeitable at all times.

         5.2  Employer Salary Reduction Account, Employer Voluntary Deduction 
Account, and ESOP Account.

              (a)  In General. A Participant shall have a vested and 
nonforfeitable interest in his Employer Salary Reduction Account, Employer
Voluntary Reduction Account, and ESOP Account after he has completed at least
five Years of Service. Prior to that time he shall have no vested interest in
such accounts.

              (b)  Accelerated Vesting. Notwithstanding section 5.2(a) above but
subject to Section 4.4, a Participant shall be fully vested and have a
nonforfeitable interest in his entire Employer Salary Reduction Account,
Employer Voluntary Deduction Account, and ESOP Account if--



                                       22
<PAGE>   29

                   (i)   while still an Employee, he attains age 65;

                   (ii)  the Participant terminates employment with his Employer
for reasons described in Section 9.1(a), (b) or (c); or

                   (iii) while he is an Employee, contributions to the Plan are
completely discontinued or the Plan is terminated, or the Plan is partially
terminated and such Participant is affected by such partial termination; OR.

                   (iv)  while he is an Employee, his account balance is
transferred to the Savings Plan in accordance with Section 3.3 (in which case
such account balance shall be vested under the recipient plan).


                        ARTICLE VI INVESTMENT PROVISIONS

         6.1  Investment of Contributions. Employer contributions under sections
4.2, 4.3, and 4.4 and Employee contributions shall be invested in accordance
with the following provisions:

              (a)  The Employer contributions made pursuant to section 4.3(a), 
(c), and (d) shall be invested in the MCN Stock Fund (through each Participant's
ESOP Account), which fund is described in Article VII.

              (b)  Each Participant shall, by direction to the Company in the 
form prescribed by the Company, direct that the Employer contributions made
pursuant to section 4.2 and Employee contributions, including those made as a
Salary Reduction, be invested in such funds offered by the Trustee as are
selected by the Company.

         Employee contributions, including those made as a Salary Reduction, and
the portion of Employer contributions referenced in section 6.1(b) above, need
not be invested in the same fund. A Participant shall direct the manner in which
the total of such contributions and such Employer contributions referenced in
section 6.1(b) above shall be divided, equally or otherwise, among the funds.

         6.2  Change of Investment Direction. Any investment direction given by 
a Participant under section 6.1 shall be deemed to be a continuing direction
until changed by the Participant. A Participant may change any such direction in
accordance with such procedures as the Company may from time to time provide and
apply in a nondiscriminatory manner.

         6.3  Transfers Between Investment Funds. A Participant may direct that 
all or any part of the value of his interest in any investment fund be
transferred to one or more of the other funds except that a Participant may not
transfer any amount from the MCN Stock fund to the extent that the balance
remaining in such fund immediately after the transfer would be less than the
value of his ESOP Account.

         A transfer of all or any part of the value of a Participant's interest
in the Fixed Income fund may from time to time be restricted by the terms of 
agreements which govern the


                                       23
<PAGE>   30


investment of assets in such fund, in which event the Company shall give notice 
of such restrictions to the Participants.

                          ARTICLE VII INVESTMENT FUNDS

         7.1  Investment Funds. The Trustee shall establish, operate, and
maintain the following funds exclusively for the collective investment and
reinvestment of monies directed by the Company to be invested in such funds on
behalf of Participants:

              (a)  MCN Stock Fund. An MCN Stock fund which shall be invested 
solely in MCN Stock.

              (b)  Fixed Income Fund. A Fixed Income fund which shall be 
invested, except as hereinafter provided, in marketable fixed income securities
or accounts maintained by financial institutions which provide for fixed or
variable rates of interest for specified periods of time. The terms of such
agreements and the selection of such institutions shall be determined by the
Company. Investment advisors for marketable fixed income securities may use
fixed income futures and options to reduce the effect of market volatility.

              (c) Other Funds. Such other funds offered by the Trustee as the
Company may select.

         Notwithstanding the foregoing, the Trustee or the investment manager,
as the case may be, shall invest such portion of the assets of the funds as the
Company may deem necessary or appropriate to facilitate the administration of
such funds in any short-term fixed income fund as may be established under any
common, commingled, or collective trust for employee benefit plans established
and maintained by the Trustee.

         7.2   Management of Investment Funds. Except as otherwise provided in 
this Article VII, the ownership of the assets and investments of the funds shall
be in the Trustee as such; and the Trustee shall have in respect of any and all
assets of the funds the same powers as if it were absolute owner thereof.

         7.3  Voting of MCN Stock.

              (a)  Instructions from Participants. The Trustee shall vote, in 
person or by proxy, shares of MCN Stock held by the Trustee in the MCN Stock
fund in accordance with instructions obtained from Participants.

              Each Participant shall be entitled to give voting instructions 
with respect to the number of shares of such respective stock which bears the
same ratio to the total number of shares held by the Trustee on the record date
as the number of shares allocated to the respective stock fund account of such
Participant as of the Valuation Date preceding such record date bears to the
total number of shares allocated to the respective stock fund accounts of all
Participants as of such Valuation Date, excluding shares allocated to the
accounts of persons whose accounts have been distributed prior to such record
date. Written notice of any meeting of stockholders of MCN Energy Group Inc. and
a request for voting instructions shall be given by the Company or the Trustee,
at such time and in such manner as the Company shall determine, to each
Participant entitled to give instructions for the voting of stock at such 


                                       24
<PAGE>   31

meeting. Shares with respect to which no voting instructions are received
from Participants and unallocated shares of the ESOP shall be voted by the
Trustee in the same proportion as shares for which voting instructions are
received from Participants. The Trustee shall combine and vote fractional shares
to the extent possible to reflect the voting instructions of Participants.

              (b)  Confidentiality. The instructions received by the Trustee
from Participants shall be held by the Trustee in strict confidence and shall
not be divulged or released to any person, including officers or employees of
the Company or any Affiliated Company

         7.4  Tender Offers.

             (a) Rights of Participants. Notwithstanding any other provisions of
this instrument, in the event an offer is made generally to the shareholders of
MCN Energy Group Inc. to transfer all or a portion of the common stock of MCN
Energy Group Inc. in return for valuable consideration including, but not
limited to, offers regulated by section 14(D) of the Securities Exchange Act of
1934, as amended, each Participant owning a beneficial interest in the MCN Stock
fund shall have the sole and exclusive right to decide if the common stock
representing his interest in such fund shall be tendered. Each Participant shall
have the right, to the extent the terms of the tender offer so permit, to direct
the withdrawal of such shares from tender. A Participant shall not be limited as
to the number of instructions to tender or withdraw from tender which he can
give; provided, however, the Participant shall not have the right to give
instructions to tender or withdraw from tender after a reasonable time
established by the Trustee pursuant to section 7.4(c) below.

              (b)  Duties of the Company. Within a reasonable time after the 
commencement of a tender offer, the Company shall provide to each Participant
having an ownership interest in the MCN Stock fund--

                    (i)   the offer to purchase as distributed by the offeror to
                          the shareholders of MCN Energy Group Inc.,

                    (ii)  a statement of the shares representing his interest in
                          the MCN Stock fund as of the most recent information
                          available from the Company, and

                    (iii) directions as to the means by which a Participant can 
                          give confidential instructions to the Trustee with
                          respect to the tender. The Company shall establish and
                          pay for a means by which a Participant can
                          expeditiously deliver to the Trustee instructions with
                          respect to the tender.

              (c)  Duties of the Trustee. The Trustee shall follow the 
instructions of the Participants with respect to the tender offer. The Trustee
shall not tender shares for which no instructions are received. Unallocated
shares of MCN Stock of the ESOP shall be tendered or exchanged by the Trustee in
the same proportion as the allocated shares for which the Trustee has received
direction are tendered or exchanged, subject to the terms of any loan or pledge
agreement covering such shares. On the basis of its ability to comply with the
terms of the



                                       25
<PAGE>   32

offer, the Trustee shall establish a reasonable time after which it shall not
accept the instructions of Participants.

              (d) Confidentiality. The instructions received by the Trustee from
Participants shall be held by the Trustee in strict confidence and shall not be
divulged or released to any person, including officers or employees of the
Company or any Affiliated Company.

         7.5  Named Fiduciary Status. For purposes of sections 7.3 and 7.4, each
Participant is hereby designated a "named fiduciary" within the meaning of ERISA
section 403(a)(1) with respect to shares of MCN Stock as to which he is entitled
to make voting or tender offer decisions.

         7.6  Expenses of Funds. Brokerage commissions, transfer taxes, and
other charges and expenses in connection with the purchase and sale of
securities for a fund shall be charged to the fund. Any income and other taxes
payable with respect to a fund shall likewise be charged to the fund.


                 ARTICLE VIII ACCOUNTS AND RECORDS OF THE PLAN

         8.1  Company to Maintain Accounts.

              (a)  The Company shall maintain, or cause to be maintained, for 
each Participant--

                   (i)   an Investment Plan Account attributable to Voluntary 
Deduction contributions and related Employer contributions under section 4.2,
and

                   (ii)  a separate account attributable to Salary Reduction 
contributions and related Employer contributions under section 4.2, each of
which shall be composed, to the extent required by the investment directions of
the particular Participant, of a MCN Stock fund account, a Fixed Income fund
account, and an account for each other applicable fund in which his
contributions and related Employer contributions are invested.

              (b)  The Company also shall maintain, or cause to be maintained, 
for each Participant--

                   (i)   an ESOP Account attributable to Employer contributions 
under section 4.3(a), (c) and (d), and

                   (ii)  shares of MCN Stock allocated to the Participant 
pursuant to section 13.4(d), each of which shall be composed of a MCN Stock fund
account and, to the extent diversification elections are made by the Participant
under section 13.5, such other accounts as the Company or its delegate deems
necessary or appropriate in giving effect to the diversification requirements of
section 13.5.

         The Company shall maintain, or cause to be maintained, all necessary
records.


                                       26
<PAGE>   33

         8.2  Plan Accounting. The interests of each Participant in the funds
shall be his proportionate share of the value of such funds as of any Valuation
Date. The Participant's proportionate share may be determined under any
accounting method selected by the Company that allocates fairly, in the opinion
of the Company, the investment gains and losses by or on behalf of each
Participant to the fund and that complies with the requirements of the Code and
the Regulations thereunder. The value of Participants' fund accounts shall be
redetermined as of each Valuation Date.

         8.3  Valuation of Funds. The value of a fund as of any Valuation Date
shall be the market value of all assets (including any uninvested cash) held by
the fund as determined by the Trustee reduced by the amount of any accrued
liabilities of the fund on such Valuation Date. The Trustee's determination of
market value shall be binding and conclusive upon all parties.

         To the extent any Employer securities held by the Plan are not readily
tradable on an established securities market, valuation of such securities shall
be made by an independent appraiser who meets requirements similar to the
requirements of the regulations prescribed under Code Section 170(a)(1).

         8.4  Valuation of Investment Plan Account. The value of a Participant's
Investment Plan Account as of any Valuation Date shall be the sum of the values
of his MCN Stock fund account, Fixed Income fund account, and any other of his
fund accounts attributable to Salary Reductions, Voluntary Deductions, and
Employer Contributions under section 4.2.

         8.5  Valuation of ESOP Account. The value of a Participant's ESOP
Account as of any Valuation Date shall be the sum of--

              (a)  the value of his MCN Stock Fund account attributable to
Employer contributions on his behalf under section 4.3(a), (c) and (d) and
shares of MCN Stock allocated to his ESOP Account under section 13.4(d); and

              (b)  the sum of the values of his Fixed Income fund account and 
any other of his fund accounts attributable to diversification elections under
section 13.5.

         8.6  Valuation of Plan Account. The value of a Participant's Plan
Account as of any Valuation Date shall be the sum of the values of his MCN Stock
fund account, Fixed Income fund account, and any other investment fund accounts
maintained on his behalf under the Plan. 

         8.7  Company to Furnish Annual Statements of Value of Plan. The Company
shall, not less frequently than annually, distribute to each Participant in the
Plan a statement setting forth the Plan Account of such Participant. Such
statement shall be deemed to have been accepted as correct unless written notice
of objections thereto is received by the Company or the Employer within 30 days
after the distribution of such statement to the Participant.

         8.8  Trust Agreement. A Trust has been established to fund benefits
under the Plan. The Employers may, without further reference to or action by any
Employee or Participant, from time to time enter into further agreements with
the Trustee and make such amendments to such Trust Agreement or such further
agreements as they may deem necessary or desirable to carry out the Plan, and
may take such other steps and execute such other instruments as the Employers
may deem necessary or desirable to put the Plan into effect or to carry it out.



                                       27
<PAGE>   34

                 ARTICLE IX DISTRIBUTIONS, WITHDRAWALS AND LOANS

         9.1  Distribution Upon Termination of Employment Entitling Participant
to Value of Plan Account. Upon--

              (a)  termination of a Participant's employment with his Employer
due to retirement on his Normal Retirement Date or his Disability Retirement
Date,

              (b)  the death of the Participant,

              (c)  termination of a Participant's employment with his Employer 
or placement on inactive payroll because of total and permanent disability or
legally established mental incompetency of the Participant not qualifying the
Participant for retirement hereunder, or

              (d)  termination of a Participant's employment with his Employer
under any circumstances after the Participant has satisfied the Vesting
Requirement,

         the Company shall, subject to the provisions of sections 9.7 and 9.9, 
direct the Trustee to distribute to the Participant, or, in a proper case his 
designated beneficiary or legal representative, the value of the Participant's 
Plan Account in a lump sum.

         9.2  Distribution Upon Termination of Employment Under Circumstances
Resulting in Forfeiture of Employer Contributions. Upon termination of a
Participant's employment under circumstances other than those described in
sections 9.1 and 9.7(c)(ii), the Company shall, subject to the provisions of
section 9.7, direct the Trustee to distribute to the Participant an amount equal
to the value of the Participant's Employee Pre-1987 Voluntary Deduction Account,
Employee Post-1986 Voluntary Deduction Account, and Employee Salary Reduction
Account each of which shall be fully vested and nonforfeitable at all times.
Subject to Section 4.4,The Participant's Employer Voluntary Deduction Account,
Employer Salary Reduction Account, and ESOP Account shall be forfeited and
applied in reduction of the next succeeding contribution which the Participant's
Employer would otherwise contribute to the Trust; provided, however, if such
Participant is reemployed prior to his incurring five consecutive Break in
Service Years, then following his date of reemployment the Participant's
Employer shall contribute on behalf of such Participant an amount equal to the
amount that was forfeited upon his termination of employment, and such
contribution shall be credited to the same accounts from which it was forfeited,
in the same amounts. Such contributions shall not be taken into account in
determining under section 4.10 the Annual Additions to such Participant's
Savings INVESTMENT Plan Account.

         9.3  Certain Distributions from Participant Accounts.

              (a)  In General. Any Participant may, upon notice to the Company 
in the form and timing prescribed by the Company, terminate his participation in
the Plan. Within a reasonable period of time following processing of such
termination, the Company shall direct the Trustee to distribute to the
Participant an amount equal to the value of the Participant's Employee Pre-1987
Voluntary Deduction Account and Employee Post-1986 Voluntary Deduction Account;
but only to the extent attributable to Voluntary Deduction contributions that
have been in the Plan for at least 2 years.. Prior to July 1, 1998, such a
Participant, if a Greater 


                                       28
<PAGE>   35

Michigan Local Participants, shall be ineligible to again elect to make
contributions under the Plan for a period of 12 full months from the date of
termination of participation. 

              (b)  Withdrawals After Age 59 1/2. Upon notice to the Company in
the form and timing prescribed by the Company, any Participant who has attained
age 59 1/2 may make an election, not more frequently than once every calendar
year, to withdraw all or any portion of the vested amount of his Plan Account.
Within a reasonable period of time following the processing of such election,
the Company shall direct the Trustee to distribute to the Participant as of such
Valuation Date the amount the Participant has elected to withdraw.

              (c)  Limited Withdrawal in the Event of Hardship. If a Participant
incurs a financial hardship as defined in section 9.6, he may limit the amount
of a distribution from his Voluntary Deduction Account under section 9.3(a) to
the amount necessary to satisfy the hardship and to pay any taxes resulting from
such distribution.

         9.4  In-Service Withdrawals -- General. At its discretion, the Company 
may adopt rules limiting the number of withdrawals that may be made in any Plan
Year and prescribe a minimum amount that may be withdrawn. All requests for a
withdrawal shall be submitted in a form prescribed by the Company. A Participant
may not rescind a request for withdrawal which has been submitted to the Company
unless the Company consents. A withdrawal shall be distributed as soon as
reasonably practicable after the withdrawal request is received.

         9.5  Withdrawal of Voluntary Deduction Contributions. Any Participant 
who shall have actively participated in the Plan for 24 or more calendar months
(for purposes of this section 9.5 active participation means the Participant
shall have made contributions to the Plan in each month in which compensation
was available), may, upon notice to the Company (in manner and timing prescribed
by the Company), withdraw an amount not in excess of 100 percent of his
Voluntary Deduction contributions under the Plan (but only to the extent
attributable to voluntary deduction contributions that have been in the plan for
at least 2 years), with such election to be given effect within a reasonable
period of time following processing.

         Withdrawals under this section 9.5 shall be from the MCN Stock fund,
the Fixed Income fund, or such other investment funds offered by the Trustee as
the Company shall make available for purposes of this section. If the
Participant has an account in more than one fund, he shall specify in his
direction to the Company the amount to be withdrawn from each fund. The
contributions in all funds in the Employee Pre-1987 Voluntary Deduction Account
must be withdrawn before a withdrawal is permitted from a fund in the Employee
Post-1986 Voluntary Deduction Account. The amount of an in-service withdrawal
from a specific fund in a Voluntary Deduction Account shall not exceed the
Employee's contributions in such fund prior to the withdrawal.

         9.6  Hardship Withdrawal of Salary Reduction Contributions. A
Participant may request, upon 20 days' written notice to the Company, a
withdrawal from his Salary Reduction Account if the withdrawal is necessary to
satisfy an immediate and heavy financial need of a Participant as defined below,
with such election to be given effect within a reasonable period following
processing. The amount of such withdrawal shall be limited to the Participant's
Salary Reduction contributions or the total value of the Participant's Employee
Salary Reduction Account as of the latest Valuation Date for which information
is available, whichever is smaller. Withdrawals under this section 9.6 shall be
from the MCN Stock fund, the Fixed Income fund, 


                                       29
<PAGE>   36

or such other investment funds under the Plan as the Participant specifies in
his written request for a hardship withdrawal.

         The determination of whether or not a distribution is necessary to
satisfy an immediate and heavy financial need and the amount required to be
distributed to meet the need shall be made by the Company. All determinations
regarding financial need shall be made in accordance with written procedures
established by the Company and applied in a uniform and nondiscriminatory
manner, based on all applicable facts and circumstances. Such written procedures
shall specify the requirements for requesting and receiving distributions on
account of financial need, including the forms that must be submitted and to
whom the forms are to be submitted. All determinations regarding financial need
must comply with applicable Regulations under the Code.

         For purposes of this section 9.6, a financial hardship withdrawal shall
be limited to the amount required to meet the need created by one of the
following situations:

              (a)  Expenses for medical care described in Code section 213(d) 
previously incurred by the Participant, his spouse, or any dependents of the 
Participant or necessary for these persons to obtain medical care described in
Code section 213(d).

              (b)  Costs directly related to the purchase (excluding mortgage 
payments) of the principal residence for the Participant.

              (c)  Payment of tuition, related educational fees and room and 
board expenses for the next 12 months of post-secondary education for the
Participant, his spouse, children, or dependents (as defined in Code section
152).

              (d)  The need to prevent the eviction of the Participant from his 
principal residence or foreclosure on the mortgage on the Participant's
principal residence.

         A distribution will be deemed necessary to satisfy an immediate and
heavy financial need of a Participant only if both of the following conditions
are met: (I)(1) The distribution is not in excess of the amount of the immediate
and heavy financial need of the Participant. Prior to January 1, 1999, this
amount may be increased by the lesser of the amount withheld from the
distribution under Code section 3405(c) or the remaining Salary Reduction
contributions or total value of the Salary Reduction Account, if less, after
subtracting the amount of the immediate and heavy financial need; and (II).(2)
The Participant has obtained all distributions, other than hardship
distributions, and all loans available under this Plan and all other plans
maintained by the Employer.

         If a Participant receives a hardship distribution, (A) the Participant
shall not be entitled to make Salary Reduction contributions or Voluntary
Deduction contributions (or other employee contributions to qualified or
nonqualified plans of deferred compensation, as described in applicable
regulations) for a period of one year after the hardship distribution, and (B)
the Participant may not make Salary Reduction contributions for the
Participant's taxable year immediately following the taxable year of the
hardship distribution in excess of the amount specified in Code section 402(g)
for such taxable year less the amount of the Participant's Salary Reduction
contributions for the taxable year of the hardship distribution.


                                       30
<PAGE>   37

         9.7  Time of Distributions.

              (a)  In General. Except as hereinafter provided and subject to the
provisions of section 9.9, distributions made pursuant to section 9.1 or
9.7(c)(ii) shall be made by the Trustee at the direction of the Company on such
date as the Company shall determine after consultation with the Participant or
his beneficiary, but in no event later than March 1 of the calendar year
following termination of the Participant's employment.

         Except as hereinafter provided, all other distributions or withdrawals
under this Article IX shall be paid as soon as reasonably practicable by the
Trustee at the direction of the Company. Notwithstanding any other provision of
the Plan--

                   (i)   if the vested portion of a Participant's Plan Account
has ever exceeded $5,000 (or such greater amount as permitted under the Code),
no distribution shall be made to such Participant pursuant to Section 9.1, 9.2,
9.7(c)(ii), or 9.9 prior to the date the Participant attains the age of
sixty-five (65) without written consent of the Participant; and

                   (ii)  if a distribution to a Participant is deferred pursuant
to (i), the amount that would otherwise have been distributed to such
Participant shall be invested in the Fixed Income fund or any other investment
fund under the Plan, as the Participant shall direct, except that the ESOP
Account of such Participant shall continue to be invested in the MCN Stock fund,
subject to the diversification rules set forth in section 13.5.

         A former Participant whose distribution has been deferred pursuant to
(i) above will not thereafter be eligible for withdrawals under section 9.3 or
9.5 or loans under section 9.10 but shall continue to have the voting and tender
offer rights described sections 7.3 and 7.4 and to be treated as a Participant
for purposes of Article VIII.

         A former Participant whose distribution has been deferred may initiate
a distribution upon reasonable prior written notice to the Company and shall
receive an amount equal to the vested portion of his Plan Account within a
reasonable period following the processing of such election, with such amount to
be distributed in a lump sum cash payment except that--

                   (A)   amounts invested in the MCN Stock fund shall be 
                         distributed in accordance with section 9.8,

                   (B)   such former Participant may upon reasonable  prior 
                         notice (as determined pursuant to procedures
                         established by the Company) to the Company receive a
                         partial distribution rather than a total distribution,
                         of the vested portion of his Account, but not more
                         frequently than four times per year, and

                   (C)   to the extent that such distribution comes from the
                         Fixed Income fund account, such distribution shall be
                         subject to the provisions of section 9.9.

         Notwithstanding any other provision of this Plan, if a Participant
attains age 70 1/2 and still has a balance allocated to his or her Plan Account,
a distribution shall be made under section 9.1 as if the Participant had
terminated employment in the month in which the 


                                       31
<PAGE>   38

Participant attains age 70 1/2. Such distribution shall in no event be later
than April 1 of the calendar year following the year in which the Participant
attains age 70 1/2. Distributions to such Participant shall be made annually
thereafter no later than December 31 of each year and shall be equal to at least
the minimum amount required to be distributed by Code section 401(a)(9). For
purposes of this paragraph, the life expectancy of the Participant and the
Participant's spouse shall be redetermined annually.

              (b)  Suspension of Participation. Prior to termination of his
employment, if a Participant shall cease to meet the eligibility requirements of
the Plan, his contributions and Employer contributions on his behalf shall be
suspended during the period of his ineligibility. Subject to section 3.1,
distribution of such Participant's Plan Account shall be deferred until
termination of his employment with the Company and any Affiliated Company. If
the provisions of section 3.3 relating to the transfer of a Participant's Plan
Account to the Savings Plan or its successor are not applicable-- 

                   (i)  with respect to Participants who cease to meet the 
eligibility requirements of the Plan prior to January 1, 1987, the Company shall
direct the Trustee to distribute the value of the Participant's Plan Account in
accordance with section 9.1 whether or not such termination of employment shall
be under the circumstances set forth in said section 9.1; and

                   (ii)  with respect to Participants who cease to meet the
eligibility requirements of the Plan subsequent to December 31, 1986, such
distribution shall be in accordance with section 9.1 or 9.3, whichever is
applicable.

              (c)  Transfer of Employment.

                   (i)   A transfer of employment from an Employer to an
Affiliated Company shall not be considered a termination of employment.

                   (ii)  If a Participant shall be transferred to the employ of
an Affiliated Company which has not elected to participate in the Plan,
distribution of such Participant's Plan Account shall be deferred until the date
on which he is no longer in the employ of the Company or any Affiliated Company,
whereupon the Company shall direct the Trustee to distribute the value of the
Participant's Plan Account in the manner prescribed in section 9.1, subject to
the provisions of section 9.7, whether or not termination of employment shall be
under circumstances set forth in said section 9.1.

              (d)  Special Rules Relating to Distributions in the Event of 
Death. In the event that a Participant dies before a distribution of his Plan
Account, the Company shall direct the Trustee to distribute the entire value of
his Plan Account to his beneficiary no later than March 1 of the calendar year
following the Participant's death, as provided in section 9.1. In the event of
the death of the Participant after the distribution of his Plan Account has
begun, any remaining balance in his Plan Account at the time of death will be
distributed at least as rapidly as under the method of distribution in effect at
the date of the Participant's death.

              (e)  Distribution must begin not later than the sixtieth (60th) 
day after the close of the Plan Year in which occurs the latest of (a) the
Participant's termination of employment, (b) the Participant's attainment of age
sixty-five (65), or (c) the tenth (10th) anniversary of the date the Participant
first became a Participant, unless (1) the Participant 


                                       32
<PAGE>   39

elects a later date by submitting to the Company a written statement signed by
the Participant which describes the benefit and the date on which payment of
such benefit shall commence, so long as such election does not violate the
incidental benefit rule prescribed by the Code; or (2) if the amount of the
payment required to commence on the date determined hereinabove cannot be
ascertained by such date, or if it is not possible to make such payment on such
date because the Company has been unable to locate the Participant after making
reasonable efforts to do so, a payment retroactive to such date may be made no
later than sixty (60) days after the earliest date on which the amount of such
payment can be ascertained under the Plan or the date on which the Participant
is located, whichever is applicable. For purposes of this subsection, the
failure of a Participant to consent to a distribution shall be deemed an
election to defer commencement of payment of any benefit sufficient to satisfy
this section.

         9.8  Distributions of Stock. In the case of distributions under section
9.1, 9.2, 9.3(b), 9.7(a), or 9.7(c)(ii), the value of the Participant's MCN
Stock fund account, if any, shall be paid in full shares of stock except that
cash shall be distributed in lieu of fractional shares; provided, however, that
a Participant entitled to such a distribution may elect to receive cash in lieu
of MCN Stock. Except in the case of an election to receive cash in lieu of MCN
Stock the total number of shares allocated to such account shall be distributed
from such account. Any remaining value of such account and, subject to the
provisions of section 9.9, the value of the Participant's accounts in other
funds shall be distributed in cash. Any transfer taxes payable with respect to
the distribution of shares of stock shall be charged to the respective MCN Stock
fund. Distributions pursuant to section 9.3(a) and withdrawals under sections
9.5 and 9.6 shall be paid entirely in cash. The distribution requirements of
Code Section 409(o) shall be met by the Plan, to the extent applicable.

         9.9  Distributions to certain participants from Fixed Income Fund. This
Section 9.9 shall apply only to Participants with at least one Hour of
Employment prior to May 31, 1988.

              (a)  Normal Form. Notwithstanding any provision of the Plan, other
than the final paragraph of section 9.7(a), if a distribution is to be made
under section 9.1(a) or (c) and the Participant has a Fixed Income fund account
and at least one Hour of Employment prior to May 31, 1988 and the Participant's
first Hour of Employment is prior to January 1, 1999, then unless the
Participant or legal representative shall make an election in the manner
prescribed in section 9.9(b), the value of such account (exclusive of the
portion thereof attributable to diversification elections under section 13.5)
shall be distributed by the purchase of an immediately payable single premium
annuity contract providing for monthly payments during the Participant's
lifetime and, if the Participant is married on the date payment of his benefit
commences and his spouse shall survive him, for monthly payments during the
remainder of such spouse's lifetime, each such payment to such spouse being
equal to one-half of the monthly payment received by the Participant, commencing
no later than March 1 of the calendar year following the calendar year of the
Participant's termination of employment, and delivery of such contract to the
Participant within a reasonable time after the Participant's termination of
employment.

         If a distribution is to be made under section 9.1(b) because of a
Participant's death and the Participant had a Fixed Income fund account at the
time of his death and at least one Hour of Employment prior to May 31, 1988 and
the Participant's first Hour of Employment was prior to January 1, 1999, then
unless the Participant had made or the Participant's spouse or beneficiary, as
the case may be, makes an election at the time and in the manner prescribed in
section 9.9(b), the value of the Participant's Fixed Income fund account
(exclusive of the portion thereof attributable to diversification elections
under section 13.5) shall be distributed by purchase of an immediately payable
single premium annuity contract providing 


                                       33
<PAGE>   40

for monthly payments to the Participant's spouse, or, if the Participant was not
married on the day of his death, to his beneficiary during such person's
lifetime, commencing no later than March 1 of the calendar year following the
calendar year of the Participant's death and delivery of such contract to such
person within a reasonable time after the date of Participant's death.

              (b)  Election to Reject Normal Form. Subject to the provisions of
this section 9.9(b), each Participant entitled to a distribution under section
9.9(a) (or legal representative on behalf of such a Participant) may, at any
time during the 90-day period ending on the annuity starting date, elect to have
the value of the Participant's Fixed Income fund account (exclusive of the
portion thereof attributable to diversification elections under section 13.5)
distributed by one or more of the methods set forth in section 9.9(c).

         Within 30 days after a Participant provides notice to the Company (in
the manner and timing prescribed by the Company) of his intention to retire on
his Normal Retirement Date or Disability Retirement Date, or within 30 days
after the Company receives notice of a Participant's death, or within five
business days after determining, in accordance herewith, that a Participant is
totally and permanently disabled, or within five business days after receiving
notice of the legally established mental incompetency of the Participant, if the
Participant has a Fixed Income fund account at such time, the Company shall
deliver to such Participant or his legal representative, by mail or by personal
delivery, written notice in nontechnical language explaining the terms and
conditions of the annuity provided in section 9.9(a).

         The notice shall explain the Participant's or legal representative's
right to elect an optional form of distribution and that such election may be
revoked by the Participant or legal representative at any time prior to the
annuity starting date or, if a lump sum payment is elected, prior to the first
day on which all events have occurred which entitle the Participant or legal
representative to the lump sum payment.

         The notice shall explain that a married Participant may elect a
distribution pursuant to section 9.9(c) only if the spouse consents in writing
to such election. Such written consent shall acknowledge consent to the
designated beneficiary and the optional form of distribution, neither of which
may be changed thereafter without again obtaining written spousal consent (or
the consent of the spouse expressly permits changes by the Participant without
further consent by the spouse). Such written consent shall acknowledge the
effect of such election and shall be witnessed by a notary public or by a
representative of the Company who is designated to act in such capacity by the
Company.

         If the Participant establishes to the satisfaction of the Company that
such written consent cannot be obtained because his spouse cannot be located,
the requirement of such written consent shall be waived. Any election, change,
or revocation under this section 9.9(b) shall be effective when notice is
delivered to the Company in a form approved by the Company for this purpose,
provided such election, change, or revocation is delivered prior to the annuity
starting date or, if a lump sum payment is elected, prior to the first day on
which all events have occurred which entitle the Participant or legal
representative to the lump sum payment. The notice shall explain that an
effective revocation shall result in the benefit being provided as an annuity
described in section 9.9(a).

              Subject to Section 9.14(c), such notice shall be provided no less 
than thirty (30) days and no more than ninety (90) days prior to the annuity 
starting date.




                                       34
<PAGE>   41

              (c)  Optional Forms. In addition to the form described in section
9.9(a), distribution of the value of a Participant's Fixed Income fund account
(exclusive of the portion thereof attributable to diversification elections
under section 13.5) may be made either--

                   (i)   in a lump sum payment; or

                   (ii)  by purchase of any form of single premium annuity
contract that satisfies Code section 401(a)(9) as may from time to time be
offered by the legal reserve life insurance companies with which the Trustee has
agreements governing the investment of assets in the Fixed Income fund and
delivery of such contract to the Participant or distributee within a reasonable
time after the Participant's termination of employment or death. Within five
business days after the Company receives an election pursuant to this provision,
the Company shall provide the same notice provided under section 9.9(b). An
election pursuant to this provision shall be subject to the provisions of
section 9.9(b).

         9.10 Loans. The Trustee is hereby authorized to establish a loan
program in accordance with this section 9.10. Upon application of a party in
interest (as defined in ERISA section 3(14)) who is a Participant or beneficiary
under the Plan, the Company shall direct the Trustee to make a cash loan to such
Participant or beneficiary, secured by 50 percent of the nonforfeitable value of
the Participant's Employee and Employer Salary Reduction and ESOP Accounts
determined as of the date the loan is made. The loan program shall be
administered by the Company subject to the following conditions and such other
conditions that are consistent with Labor Regulation section 2550.408b-1 and are
from time to time set forth in written administrative procedures which shall
constitute a part of the Plan and are hereby incorporated by reference:

              (a)  The term of a loan shall not extend beyond the earlier of 
four years or the date upon which the Participant or beneficiary ceases to be a
party in interest; provided, however, that the four years shall be changed to
eight years where the proceeds of the loan are used by the Participant or
beneficiary to acquire the Participant's principal residence.

              (b)  A loan shall bear interest at a reasonable rate which shall 
be based upon the prevailing interest rate charged by persons in the business of
lending money on similar commercial loans under comparable circumstances at the
time that such loan is granted, as determined by the Company and uniformly
applied.

              (c)  The amount of a loan (when added to the balance of other
outstanding loans) shall not exceed the lesser of--

                   (i)   $50,000 reduced by the excess (if any) of--

                         (A)   the highest outstanding balance of loans from the
                         Plan during the one-year period ending on the day
                         before the date on which such loan was made, over

                         (B)   the outstanding balance of loans outstanding on
                         the date such loan was made, or 



                                       35
<PAGE>   42




                   (ii)  50 percent of the nonforfeitable value of the
Participant's Employee and Employer Salary Reduction and ESOP Accounts under the
Plan which the Participant would have been entitled to receive if the
Participant's employment had terminated on the date such loan was made.

                   In no case shall a Participant be entitled to a loan under
this Plan if the amount of the proposed loan is less than $500.

              (d)  A loan shall be evidenced by a promissory note.

              (e)  Payments of principal and interest shall be made by
approximately equal payments not less frequently than monthly on a basis that
would permit the loan to be fully amortized over its term. Loan payments shall
be made by payroll deductions for Participants in active pay status.

              (f)  Appropriate disclosure shall be made pursuant to the Truth in
Lending Act to the extent applicable.

              (g)  Amounts of principal and interest received on a loan shall be
credited to the Participant's account and the outstanding loan balance shall be
considered an investment of the assets of the account. Payment of principal and
interest related to loans made from a Participant's ESOP Account shall be
credited to such Participant's ESOP Account. Payment of principal and interest
related to loans made from a Participant's Investment Plan Account shall be
credited to the Participant's Investment Plan Account and shall be invested in
the investment funds in the same proportions as the investment election then in
effect by the Participant under Article VI.

              (h)  The frequency of loans and the minimum amount for a loan 
shall be determined through uniform rules prescribed by the Company and at the
sole discretion of the Company.

              (i)  All applications for a loan shall be submitted to the Company
on a form prescribed by the Company. Distribution shall be made as soon as
reasonably practicable after the application of the loan is received. 

              (j)  If a Participant borrows from an account which is invested in
more than one fund, he shall instruct the Company as to the funds from which the
loan is to be applied; provided, however, that no borrowing shall be applied
from the MCN Stock fund unless and until the Participant's ability to borrow
from each of the other funds has been exhausted.

              (k)  A married Participant may not borrow any amount from the Plan
unless his spouse executes a written consent as hereinafter provided. Such
consent must be executed during the 90-day period ending on the date on which
the loan is made and shall specifically provide that the spouse consents both to
the loan and to the use of the Participant's Salary Reduction and ESOP Accounts
as security for the loan. The consent shall acknowledge the effect of the use of
the Participant's accounts as security for the loan and shall be witnessed by a
notary public or a representative of the Company who is designated to act in
such capacity by the Company.


                                       36
<PAGE>   43


              (l)  In the event a Participant defaults on a loan, the entire
outstanding balance of and accrued interest on the loan shall be due and payable
in accordance with the Plan's loan procedures and applicable Regulations. The
Trustee and/or Company may pursue collection on such defaulted loan by any means
generally available to a creditor where a promissory note is in default, or if
the entire amount due is not paid by such Participant following the default, the
amount of such loan default shall be charged against the "secured portion" of
the Participant's Plan Account and treated as a distribution with respect to
such Participant; provided, however, that such a charge against a Participant's
Plan Account shall not occur with respect to funds in his Employee Salary
Reduction Account at a time so as to cause a violation of Code section
401(k)(2)(B)(i).

         9.11 Definition of Employee Contributions and Employer Contributions.
For the purposes of this Article IX, a Participant's Employee contributions
shall include only those contributions made either as a Voluntary Deduction or a
Salary Reduction which have not been previously withdrawn or distributed. If a
Participant has previously had a portion of his Plan Account forfeited under
section 9.2, the Employer contributions, exclusive of those made as a Salary
Reduction to the Plan on his behalf, shall include only such Employer
contributions made subsequent to such forfeiture.

         9.12 Spousal Consent to Payment. Subject to section 9.7(a), the spouse
of a married Participant or former Participant shall be required to consent in
writing to any in-service withdrawal, loan, or distribution under the Plan to
the Participant or former Participant. The spouse's consent shall be in such
form as the Company may prescribe.

         9.13 Distributions Pursuant to a Qualified Domestic Relations Order.
Upon receipt of a domestic relations order, the Company will notify the involved
Participant and any alternate payee that the order has been received and explain
the Plan's procedures for determining whether the order is a qualified domestic
relations order as defined in Code section 414(p). After determining that the
order is a qualified domestic relations order, the Company shall direct the
Trustee to distribute or segregate the Participant's Account as provided in the
qualified domestic relations order. If required by the qualified domestic
relations order, the Trustee shall make distribution prior to the time that the
Participant, whose account is subject to distribution, could have received a
distribution.

         In a case of a dispute regarding the validity of a domestic relations
order or the amounts or identities of parties to be paid thereunder, the Company
may segregate the portion of the Participant's account in question, and may
bring an action in a court of competent jurisdiction to determine the proper
amount and/or recipient of benefits, or may submit such segregated amount to a
court of competent jurisdiction (through an interpleader action or otherwise)
until resolution of the matter. Further, if the Company receives notice that a
domestic relations order is forthcoming, the Company may suspend payments from
the Participant's Account or may follow the procedures described in the
preceding sentence, until resolution of the matter.

         9.14 Direct Rollovers of Eligible Distributions.

              (a)  General. Notwithstanding any provision of the Plan to the
contrary that would otherwise limit a distributee's election under this section,
a distributee may elect, at the time and in the manner prescribed by the
Company, to have any portion of an eligible rollover 


                                       37
<PAGE>   44


distribution paid directly to an eligible retirement plan specified by the
distributee in a direct rollover.

              (b)  Definitions.

                   (i)   Eligible rollover distribution. An eligible rollover
distribution is any distribution of all or any portion of the balance to the
credit of the distributee, except that an eligible rollover distribution does
not include: any distribution that is one of a series of substantially equal
periodic payments (not less frequently than annually) made for the life (or life
expectancy) of the distributee or the joint lives (or joint life expectancies)
of the distributee and the distributee's designated beneficiary,; or for a
specified period of ten years or more; any distribution to the extent such
distribution is required under Code section 401(a)(9), or, effective any
hardship distribution after January 1, 1999, a hardship distribution; and the
portion of any distribution that is not includible in gross income (determined
without regard to the exclusion for net unrealized appreciation with respect to
employer securities).

                   (ii)  Eligible retirement plan. An eligible retirement plan 
is an individual retirement account described in Code section 408(a), an
individual retirement annuity described in Code section 408(b), an annuity plan
described in Code section 403(a), or a qualified trust described in Code section
401(a), that accepts the distributee's eligible rollover distribution. However,
in the case of an eligible rollover distribution to the surviving spouse, an
eligible retirement plan is an individual retirement account or individual
retirement annuity.

                   (iii) Distributee. A distributee includes an Employee or
former Employee. In addition, the Employee's or former Employee's surviving
spouse and the Employee's or former Employee's spouse or former spouse who is
the alternate payee under a qualified domestic relations order, as defined in
Code section 414(p), are distributees with regard to the interest of the spouse
or former spouse.

                   (iv)  Direct rollover. A direct rollover is a payment by the
Plan to the eligible retirement plan specified by the distributee.

              (c)  Waiver of 30-Day Notice Period. If a distribution is one to
which Code sections 401(a)(11) and 417 do not apply, such distribution may
commence less than 30 days after the notice required under section
1.411(a)-11(c) of the Income Tax Regulations is given, provided that (i) the
Company clearly informs the Participant that the Participant has a right to a
period of at least 30 days after receiving the notice to consider the decision
of whether or not to elect a distribution (and, if applicable, a particular
distribution option), and (ii) the Participant, after receiving the notice,
affirmatively elects a distribution.

         9.15 Special Distribution Events. Notwithstanding anything herein to
the contrary, a Participant's Salary Reduction contributions shall not be
distributed prior to the Employee's retirement, death, disability, termination
of employment, or hardship, except that a distribution of such amounts may be
made, in accordance with Code Section 401(k)(10), upon

              (a)  termination of the Plan without establishment of another
defined contribution plan other than an employee stock ownership plan (as
defined in Code Section 4975(e) or 409) or a simplified employee pension plan
(as defined in Code Section 408(k));


                                       38
<PAGE>   45

              (b)  the disposition by MCN Energy Group Inc. or the Company to an
unrelated corporation of substantially all of the assets (as defined in Code
Section 409(e)(2)) used in the trade or business if the Company continues to
maintain the Plan after the disposition, but only with respect to Employees who
continue employment with the corporation acquiring such assets; or

              (c)  the disposition by MCN Energy Group Inc. or the Company to an
unrelated entity of its interest in a subsidiary (within the meaning of Code
Section 409(d)(3)) if the Company continues to maintain the Plan, but only with
respect to Employees who continue employment with such subsidiary.

                            ARTICLE X ADMINISTRATION

         10.1 Plan Administration and Interpretation.

              (a)  The Company shall be responsible for the administration of 
the Plan, or may designate all or a portion of such responsibility to a
committee for such purposes. The Company shall have all such powers as may be
necessary to carry out the provisions of the Plan and may from time to time
establish rules and procedures for the administration of the Plan and the
transaction of the Plan's business.

              (b)  The Company shall have the exclusive right to make any 
finding of fact necessary or appropriate for any purpose under the Plan. The
Company shall have the maximum discretion permitted by law to interpret and
construe the terms of the Plan and to resolve all issues arising under the Plan
including, but not limited to the authority to--

                   (i)   construe disputed or doubtful terms of the Plan;

                   (ii)  determine the eligibility of an individual to
participate in the Plan;

                   (iii) determine the amount, if any, of benefits to which any
Participant, former Participant, beneficiary, or other person may be entitled
under the Plan;

                   (iv)  determine the timing and manner of payment of benefits;
and

                   (v) resolve all other issues arising under the Plan.

              To the extent permitted by law, all findings of fact, 
determinations, interpretations, and decisions of the Company shall be
conclusive and binding upon all persons having or claiming to have any interest
or right under the Plan.

              The Employers shall, from time to time, on request of the Company,
furnish to the Company such data and information as the Company shall require in
the performance of its duties.

              (c)  The Company shall each month collect Employee contributions
and Employer contributions from each Employer and shall deliver the amounts
collected to the Trustee, together with instructions concerning the portions of
such total amount to be invested in each fund.


                                       39
<PAGE>   46

              (d)  The Company shall direct the Trustee to make payments of
amounts to be distributed or withdrawn from the Trust under Article IX and to
make any transfers from one fund to another directed by Participants under
section 6.3.

         10.2 Notice to Employees. All notices, reports, and statements given,
made, delivered, or transmitted to a Participant shall be deemed to have been
duly given, made, or transmitted when mailed with postage prepaid and addressed
to the Participant at the address last appearing on the books of the Employer. A
Participant may record any change of his address from time to time by written
notice filed with the Employer.

         10.3 Notices to Employers. Written directions, notices, and other
communications from Participants to the Employers shall be mailed by first class
mail with postage prepaid or delivered to such location as shall be specified
upon the forms prescribed by the Company for the giving of such directions,
notices, and other communications, and shall be deemed to have been received by
the addressee when received at such location. Any other notice to the Employers
shall be addressed--

              (a)       If intended for the Company:
                        MichCon Investment and Stock Ownership Plan
                        c/o Michigan Consolidated Gas Company
                        500 Griswold Street
                        Detroit, Michigan 48226

              (b)  If intended for any other Employer, at its principal place of
business.

         10.4 Participants' Acceptance of the Provisions of the Plan. Each
Participant at the time of becoming a Participant in the Plan and as a condition
of participation shall sign an instrument evidencing the fact that he accepts
and agrees to all provisions of the Plan.

         10.5 Audit of Plan Records. The records of the Company and the records
of the Employers in respect of the Plan shall be examined annually by a firm of
independent public accountants appointed by the Company. Such accountants shall,
on the basis of such examination, make such reports to the Company and to the
Employers as they may request. The audited records of the Company and the
Employers shall be conclusive in respect of all matters involved in the
administration of the Plan.

         10.6 Claims Procedure. If any Participant or distributee believes he is
entitled to benefits in an amount greater than those which he is receiving or
has received, he may file a claim with the Secretary of the Company. Such a
claim shall be in writing and state the nature of the claim, the facts
supporting the claim, the amount claimed, and the address of the claimant.

         The Secretary of the Company shall review the claim and, within a
reasonable period of time after receipt of the claim, give written notice by
registered or certified mail to the claimant of his decision with respect to the
claim. Such notice shall be written in a manner calculated to be understood by
the claimant and, if the claim is wholly or partially denied, set forth the
specific reasons for the denial, specific references to the pertinent Plan
provisions on which the denial is based, a description of any additional
material or information necessary for the claimant to 


                                       40
<PAGE>   47

perfect the claim, and an explanation of why such material or information is
necessary, and an explanation of the claim review procedure under the Plan.

              The Secretary shall also advise the claimant that he or his duly 
authorized representative may request a review by the Company of the denial by
filing with the Company, within 65 days after notice of the denial has been
received by the claimant, a written request for such review. The claimant shall
be informed that he may have reasonable access to pertinent documents and submit
comments in writing to the Company within the same 65-day period. If a request
is so filed, review of the denial shall be made by the Company and the claimant
shall be given written notice of the Company's final decision. Such notice shall
be provided within 60 days after receipt of such request. Such notice shall
include specific reasons for the decision and specific references to the
pertinent Plan provisions on which the decision is based and shall be written in
a manner calculated to be understood by the claimant.

         10.7 Effect of a Mistake. In the event of a mistake or misstatement as
to the eligibility, participation, or service of any Participant, or the amount
of payments made or to be made to a Participant or beneficiary, the Company
shall, if possible, adjust the Plan's records and cause to be withheld or
accelerated or otherwise make adjustment of such amounts of payments as will in
its sole judgment result in the Participant or beneficiary receiving the proper
amount of payments under the Plan.

                      ARTICLE XI AMENDMENT AND TERMINATION

         11.1 Amendment. The Company may at any time and from time to time amend
or modify the Plan by written instrument duly adopted by the Board of Directors
of the Company or by a designee of the Board. Any such amendment or modification
shall become effective on such date as the Company shall determine, may apply to
Participants in the Plan at the time thereof as well as future Participants, but
may not reduce the Plan Account of any Participant as of the date of adoption of
such amendment or modification.

         11.2 Withdrawal. If an Employer shall withdraw from the Plan under
section 12.2, or if an Employer shall adopt an amendment to the Plan which shall
render impracticable the continued administration of the Plan as a joint plan of
the several Employers, the Company shall determine the portions of the various
funds held by the Trustee which are applicable to the Participants of such
Employer and shall direct the Trustee to segregate such portions in a separate
trust. Such separate trust shall thereafter be held and administered as a part
of the separate plan of such Employer. After such portions of the funds have
been segregated in a separate trust, no such Participant or any distributee with
respect to such Participant shall have any right to any benefit under the Plan
or any claim against the Trust.

         11.3 Termination. Any Employer may at any time terminate its
participation in the Plan by resolution of its Board of Directors without
obtaining the consent of or giving notice to any Participant or collective
bargaining representative. In the event of any such termination, the Company
shall determine the portions of the various funds held by the Trustee which are
applicable to the Participants of such Employer and shall direct the Trustee to
distribute such portions to such Participants ratably in proportion to the
values of their respective fund accounts; provided, however, amounts
attributable to a Participant's Elective Deferrals shall not be distributed on
account of such termination if the Employer, after such termination, maintains a
defined contribution plan (other than an employee stock ownership plan or a
simplified 



                                       41
<PAGE>   48

employee pension). The portions of the MCN Stock fund so distributed shall be
distributed in kind except that cash shall be distributed in lieu of fractional
shares. The portions of the Fixed Income fund and other investment funds so
distributed shall be distributed in cash or in kind, or partly in cash and
partly in kind, as determined by the Company.

         Upon termination or partial termination of the Plan by any Employer or
upon the complete discontinuance of contributions by any Employer, the benefits
under the Plan of all affected Participants employed or formerly employed by
such Employer shall become nonforfeitable.

         11.4 Allocation of Funds Between Employers. The portion of a fund
applicable to Participants of a particular Employer shall be an amount which
bears the same ratio to the value of the fund which the aggregate value of the
fund accounts of Participants employed by such Employer bears to the total value
of the fund accounts of all Participants.

         11.5 Trust to be Applied Exclusively for Participants and Their
Beneficiaries. Subject to section 13.3, any provision of the Plan to the
contrary notwithstanding, it shall be impossible for any part of the Trust to be
used for or diverted to any purpose not for the exclusive benefit of
Participants and their beneficiaries either by operation or termination of the
Plan, by power of amendment, or by other means.

         Notwithstanding the preceding paragraph, if a contribution is made to
the Trust by an Employer by a mistake of fact, then such contribution shall be
returned to such Employer within one year after the payment of the contribution;
and if any part or all of a contribution is disallowed as a deduction under Code
section 404, then to the extent such contribution is disallowed as a deduction
it shall be returned to such Employer within one year after the disallowance.
All Employer contributions are conditioned upon their deductibility under Code
section 404.

                ARTICLE XII PARTICIPATION BY AFFILIATED COMPANIES


         12.1 Adoption of the Plan. Any Affiliated Company may become a
participating Employer under the Plan by (a) taking such corporate action as
shall be necessary to adopt the Plan, and (b) executing and delivering such
instruments and taking such other action as may be necessary or desirable to put
the Plan into effect with respect to such Affiliated Company.

         The Plan shall become effective with respect to each particular
Affiliated Company as of a date to be determined by the Board of Directors of
such Employer after complying with all legal requirements pertaining to the
participation of such Employer in the Plan.

         12.2 Withdrawal from the Plan. Any Employer may withdraw from
participation in the Plan at any time by filing with the Company a duly
certified copy of a resolution of its Board of Directors to that effect and
giving notice of its intended withdrawal to the Company, the other Employers,
and the Trustee at least 30 days prior to the effective date of withdrawal.

         12.3 Company as Agent for Employers. Each Employer other than the
Company, hereby appoints, and each other corporation which shall become an
Employer pursuant to section 12.1 or 13.7 by so doing shall be deemed to have
appointed the Company its agent to 



                                       42
<PAGE>   49

exercise on its behalf all of the powers and authorities hereby conferred upon
the Employers by the terms of the Plan, including, but not by way of limitation,
the power to amend, restate, and terminate the Plan. The authority of the
Company to act as agent shall continue unless and until the portion of the Trust
fund held for the benefit of Employees of the particular Employer and their
beneficiaries is set aside in a separate trust as provided in section 11.2.


              ARTICLE XIII SPECIAL PROVISIONS RELATING TO THE ESOP


         13.1 Establishment of ESOP. The MichCon Employee Stock Ownership Plan
for Union Employees was originally established effective as of April 1, 1989.
Each Employer shall make contributions to the ESOP in accordance with section
4.3 hereof and the assets of the ESOP shall be invested at all times primarily
in MCN Stock. The Company from time to time may direct the Trustee to incur debt
in accordance with section 13.4 hereof to finance the acquisition of MCN Stock.

         13.2 ESOP Account. The Company shall establish an ESOP Account in the
name of each Participant to which there shall be credited or charged--

              (a)  the Employer contributions under section 4.3(a), (c) and (d)
hereof made on behalf of such Participant;

              (b)  the shares allocated to the Participant pursuant to section
13.4(d) hereof; and

              (c)  the investment gains and losses on such amounts.

A Participant's ESOP Account shall be invested only in the MCN Stock fund,
except to the extent that monies diversified under section 13.5 may, at the
Participant's election, be directed to the Equities fund, the Senior Securities
fund, or the Fixed Income fund.

         13.3 Discrimination Testing. For purposes of the limitations on Salary
Reduction contributions set forth in section 4.7, the ESOP and non-ESOP portions
of the Plan shall be tested separately. For purposes of such testing--

              (a)  the ESOP portion of the Plan shall mean Employer 
contributions under section 4.3(a) made on behalf of the Participant and the
shares allocated to a Participant's ESOP Account pursuant to section 13.4(d);
and

              (b)  the non-ESOP portion of the Plan shall mean all Elective
Deferrals, Voluntary Deductions and Employer contributions under section 4.2.

         13.4 Loans.

              (a)  Stock Acquired with Exempt Loan. The Company may direct the
Trustee to incur a loan on behalf of the ESOP in a manner and under conditions
which will cause the loan to qualify as an "exempt loan" within the meaning of
Code section 4975(d)(3). A loan shall be used primarily for the benefit of
Participants and their beneficiaries. The proceeds of each



                                       43
<PAGE>   50

such loan shall be used, within a reasonable time after the loan is obtained,
only to purchase MCN Stock, to repay the loan, or to repay any prior loan.

         Any such loan shall provide for a reasonable rate of interest and an
ascertainable period of maturity, and shall be without recourse against the
Plan. Any such loan shall be secured solely by shares of MCN Stock acquired with
the proceeds of the loan and shares of MCN Stock that were used as collateral on
a prior loan which was repaid with the proceeds of the current loan.

         MCN Stock acquired with the proceeds of a loan, including shares
pledged as collateral, shall be placed in a Suspense Account and released in
accordance with subsection (b) below as the loan is repaid as if all shares in
the Suspense Account were pledged. MCN Stock released from the Suspense Account
shall be allocated in the manner described in subsection (d) below.

         No person entitled to payment under a loan made pursuant to this
section 13.4 shall have recourse against any assets of the Plan other than the
MCN Stock used as collateral for the loan, Employer contributions under section
4.3 that are available to meet obligations under the loan, and earnings
attributable to such collateral and the investment of such contributions.
Employer contributions under section 4.3(b) made with respect to any Plan Year
during which the loan remains unpaid, and earnings on such contributions, shall
be deemed available to meet obligations under the loan, unless otherwise
provided by the Employer at the time such contributions are made.

              (b)  Release of Pledged Shares. Any pledge of MCN Stock as
collateral under this section 13.4 shall provide for the release of shares so
pledged upon the payment of any portion of the principal of the loan. Shares so
pledged shall be released in the proportion that the principal paid on the loan
bears to the total principal amount of the loan, as provided in Treasury
Regulation 54.4975-7(b)(8)(ii). The number of shares of MCN Stock that shall be
released with each principal payment on the loan shall be equal to the number of
shares of MCN Stock held as collateral on the loan immediately prior to the
release multiplied by a fraction the numerator of which is the amount of
principal of the loan repaid on such date and the denominator of which is the
sum of the numerator plus the remaining outstanding principal amount of the loan
after giving effect to the repayment of principal of the loan on such date. Each
loan under this section 13.4 shall comply with the requirements of Treasury
Regulation 54.4975-7(b)(8)(ii). If such a loan provides for monthly principal
payments, shares of MCN Stock shall be released monthly.

              (c)  Repayment of Loan. Payments of principal and interest on any
loan under this section 13.4 shall be made by the Trustee at the direction of
the Company solely from-- 

                   (i)   the proceeds of such loan, if any portion of such
proceeds are used for such purpose within a reasonable period of time after the
loan is obtained as provided in section 13.4(a) above;

                   (ii)  Employer contributions under section 4.3(b) available 
to meet obligations under the loan;

                   (iii) earnings from the investment of such contributions;


                                       44
<PAGE>   51

                   (iv)  earnings attributable to MCN Stock acquired with the
proceeds of such loan, whether allocated or unallocated;

                   (v)   the earnings on other allocated shares of MCN Stock 
held by the ESOP if the Internal Revenue Service, by private letter ruling,
advises the Company that the use of such earnings to repay the loan will be
deductible under Code section 404(k)(2)(C) and will not violate the requirements
of Code section 4975; and

                   (vi)  the proceeds of a subsequent loan made to repay the
loan.

              The contributions and earnings available to pay a loan must be
accounted for separately by the Company until all loans under this section 13.4
have been paid. If dividends on MCN Stock allocated to the ESOP Account of any
Participant are used to repay any loan, shares of MCN Stock with a fair market
value not less than the amount of such dividends shall be allocated in
accordance with section 4.3(c) to the ESOP Account of such Participant prior to
the end of the Plan Year during which (but for the use of the dividends to repay
the loan) such dividend would have been allocated to the ESOP Account of such
Participant.

              (d)  Allocation of Released Shares. Subject to the limitations in
section 4.10 on Annual Additions to a Participant's accounts, shares of MCN
Stock released from a Suspense Account described in section 13.4(a) shall be
allocated immediately to the ESOP Accounts of each Participant in the proportion
that the contribution that would be required to be made on behalf of such
Participant under section 4.3(a)(i) for the applicable period if no shares were
allocated under section 4.3(a)(ii) during such period bears to the total of all
Employer contributions that would be required under section 4.3(a)(i) hereof for
the applicable period if no shares were allocated under section 4.3(a)(ii)
during such period.

         13.5 Diversification. Any Participant or any former Participant whose
distribution has been deferred pursuant to section 9.7(a), who, in either case,
has completed at least ten years of participation in the Plan, and who has
attained the age of 55 is a "Qualified Participant". Any Qualified Participant
shall have the right to make an election to direct the investment of a portion
of his ESOP Account. Such a Participant may elect within 90 days after the close
of each Plan Year in the six plan-year period beginning with the first Plan Year
in which the individual becomes a Qualified Participant to diversify 25 percent
of his ESOP Account, less any amount to which a prior election applies. In the
case of the last year to which an election applies, 50 percent shall be
substituted for 25 percent.

              The portion of a Qualified Participant's ESOP Account which is
eligible for diversification may be invested in the Fixed Income fund and/or any
other investment funds under the Plan, in any combination thereof.

         13.6 Put Option. If MCN Stock becomes not readily tradable on an
established market, then any Participant who is otherwise entitled to a
distribution of his ESOP Account, shall have the right (hereinafter referred to
as "Put Option") to require that his Employer repurchase any MCN Stock allocated
to his ESOP Account under a fair valuation formula. The Put Option shall be
exercisable only by written notice to the Participant's Employer during the
60-day period immediately following the date of distribution and if the Put
Option is not exercised within such 60-day period, then it can be exercised for
an additional period of 60 days 



                                       45
<PAGE>   52


in the following Plan Year. The period during which the Put Option is
exercisable shall not include any time when a Participant is unable to exercise
it because his Employer is prohibited from honoring it by applicable federal or
state law. This Put Option shall be nonterminable within the meaning of Treasury
Regulation 54.4975-(11)(a)(ii).

         The amount paid for MCN Stock under the Put Option shall be paid in
substantially equal periodic payments (not less frequently than annually) over a
period beginning not later than 30 days after the exercise of the Put Option and
not exceeding five years. There shall be adequate security provided and
reasonable interest paid on the unpaid balance due under this section 13.6.

         13.7 Purchase of MCN Stock. The ESOP may acquire shares of MCN Stock on
a national securities exchange, from the Company or any Affiliated Company or
otherwise; provided, however, that if any shares of MCN Stock are purchased from
the Company or any Affiliated Company, the price shall not exceed an amount
which constitutes adequate consideration (as defined in ERISA section 3(18) and
any Regulations thereunder) and such purchase shall satisfy all other
requirements of ERISA and the Code applicable to such purchases. Except as
provided in section 13.6 or as otherwise required by applicable law, no shares
of MCN Stock acquired by the ESOP shall be subject to a put, call, or other
option, or buy-sell or similar arrangement while held by and when distributed
from the Plan, whether or not any part of the Plan is then an ESOP. The
protection afforded to Participants in the preceding sentence is nonterminable
within the meaning of Treasury Regulation section 54.4975-(1)(a)(ii).

                           ARTICLE XIV MISCELLANEOUS

         14.1 Beneficiary Designation. Subject to the provisions of section 9.9
and this section 14.1, each Participant shall have the right to designate a
beneficiary or beneficiaries to receive any distribution to be made under
section 9.1 upon the death of such Participant, or, in the case of a Participant
who dies subsequent to termination of his employment but prior to the
distribution of the entire amount to which he is entitled under the Plan, any
undistributed balance to which such Participant would have been entitled.

         In the event of the death of a Participant whose spouse survives him,
the beneficiary of the Participant shall be his surviving spouse unless such
spouse has consented in writing to the designation of another beneficiary or
beneficiaries. Any such written consent shall acknowledge the effect of such
election and shall be witnessed by a notary public or by a representative of the
Company who is designated to act in such capacity by the Company. In the event a
Participant dies without a surviving spouse, or, in the event the surviving
spouse of a Participant has executed the written consent hereinabove described,
any distributions to be made under section 9.1 upon the death of the Participant
shall be made to his designated beneficiary or beneficiaries. If the Participant
establishes to the satisfaction of the Company or its designated representative
that such written consent cannot be obtained because his spouse cannot be
located, the requirement of such written consent shall be waived.

         If no beneficiary has been named by a Participant who dies without a
surviving spouse or if the beneficiary designated by such a Participant or by a
Participant whose surviving spouse has executed the written consent hereinabove
described has predeceased the Participant or such designated beneficiary has
died prior to complete disbursement of the 


                                       46
<PAGE>   53


Participant's Plan Account, the value of his account, or the undistributed
portion thereof, shall be paid by the Trustee at the direction of the Company--

              (a)  to the surviving spouse of such deceased Participant, if any;

              (b)  if there shall be no surviving spouse, to the surviving
children of such deceased Participant, if any, in equal shares;

              (c)  if there shall be no surviving spouse or surviving children,
to the executors or administrators of the estate of such deceased Participant;
or

              (d)  if no executor or administrator shall have been appointed for
the estate of such deceased Participant, to the person or persons who would be
entitled to the personal estate of such deceased Participant under the laws of
his state of domicile if he had died leaving no will.

         In the event that a Participant and his spouse die under circumstances
such that it is not clear whether the spouse survived the Participant, the
Participant shall be presumed to have survived the spouse.

         14.2 Incompetency. Any distribution under this Plan which is payable to
a beneficiary who is a minor or to a Participant or beneficiary who, in the
opinion of the Company, is unable to manage his affairs by reason of illness or
mental incompetency, may be made to or for the benefit of any such Participant
or beneficiary in such of the following ways as the Company shall direct:

              (a)  Directly to any such minor beneficiary, if, in the opinion of
the Company, he is able to manage his affairs;

              (b)  To the legal representative of any such Participant or
beneficiary; or

              (c)  To some near relative of any such Participant or beneficiary
to be used for the latter's benefit.

         14.3 Expenses. Except as otherwise provided in the Plan, all costs and
expenses incurred in administering the Plan, including the expenses of the
Company, the fees and expenses of the Trustee, the fees of its counsel, and
other administrative expenses, shall be borne by the Employers in such
proportions as the Company shall determine to be equitable and proper having
regard to the nature of the particular expense.

         14.4 Nonassignability. Except as may be required to comply with a
qualified domestic relations order (as defined in Code section 414(p)), it is a
condition of the Plan, and all rights of each Participant shall be subject
thereto, that no right or interest of any Participant in the Plan or in a Plan
Account shall be assignable or transferable in whole or in part, either directly
or by operation of law or otherwise, including, but not by way of limitation,
execution, levy, garnishment, attachment, pledge, or bankruptcy but excluding
devolution by death or mental incompetency, and no right or interest of any
Participant in the Plan or in his Plan Account shall be liable for, or subject
to, any obligation or liability of such Participant.


                                       47
<PAGE>   54

         14.5 Employment Noncontractual. The Plan confers no right upon any
Employee to continue in employment.

         14.6 Merger or Consolidation with Another Plan. A merger or
consolidation with, or transfer of assets or liabilities to, any other plan
shall not be effected unless the terms of such merger, consolidation, or
transfer are such that each Participant, distributee, beneficiary, or other
person entitled to receive benefits from the Plan would, if the Plan then
terminated, receive a benefit immediately after the merger, consolidation, or
transfer which is equal to or greater than the benefit such person would have
been entitled to receive immediately before the merger, consolidation, or
transfer if the Plan had then terminated.

         If any other plan shall be merged into and become a part of this Plan,
each Participant or the person entitled to receive a benefit under such other
plan shall be entitled to receive a benefit under this Plan which is equal to
the benefit such person would have been entitled to receive had such other plan
terminated immediately before the merger.

         14.7 Continuance by a Successor. In the event that any Employer
corporation shall be reorganized by way of merger, consolidation, transfer of
assets, or otherwise, so that another Affiliated Company shall succeed to all or
a portion of such Employer's business, such successor corporation, with the
consent of each other participating Employer, may be substituted for such
Employer under the Plan by adopting the Plan and becoming a party to the Trust
Agreement. Employee contributions and Employer contributions shall be
automatically suspended from the effective date of any such reorganization until
the date upon which the substitution of such successor corporation for the
Employer under the Plan becomes effective. If, within 90 days from the effective
date of any such reorganization, such successor corporation shall not have
become a party to the Plan, or, if the Employer shall adopt a plan of complete
liquidation other than in connection with a reorganization, the Plan shall be
automatically terminated with respect to Employees of such Employer as of the
close of business on the ninetieth day following the effective date of such
reorganization or as of the close of business on the date of adoption of such
plan of complete liquidation, as the case may be, and the Trustee shall
distribute the portion of the Trust applicable to Participants of such Employer
in the manner provided in section 11.3. 

         14.8 USERRA Rights. Notwithstanding any provision of the Plan to the 
contrary, contributions, benefits and service credit with respect to qualified
military service will be provided in accordance with Code Section 414(u), to the
extent applicable. Loan repayments will be suspended under this Plan as
permitted under Code Section 414(u).

         14.9 Construction. Unless the context clearly requires otherwise--

              (a) the masculine pronoun whenever used shall include the
feminine, the singular shall include the plural, and vice versa, and

              (b) headings of Articles and sections herein are included solely
for convenience, and if there is any conflict between such headings and the text
of the Plan, the text shall control.


         ARTICLE XV REDESIGNATION OF ESOP AND DISTRIBUTION OF DIVIDENDS


                                       48
<PAGE>   55

         This Article XV designates that part of the non-ESOP portion of the
Plan which is invested in the MCN Stock Fund becomes part of the ESOP portion of
the Plan. This Article XV also sets forth certain provisions regarding the
operation of the ESOP portion of the Plan, such provisions to supersede any
contrary provisions of the Plan. This Article XV (including provisions regarding
distribution of dividends) shall become effective as of January 1, 1998 with
regard to dividends distributed on or after that date.

         Except as specifically provided in this Article XV, the provisions of
this Article XV, including the redesignation of the ESOP portion of the Plan
described herein, shall not affect any beneficiary designations or any other
applicable agreements, elections, or consents that Participants, spouses, or
beneficiaries validly executed under the terms of the Plan before the execution
date of the Plan amendment which first adopts this Article XV, and such
designations, agreements, elections and consents shall continue to apply in the
same manner as they did prior to such amendment.

         The ESOP, as set forth in this Article XV, is intended to meet with
requirements of an employee stock ownership plan, as defined in Section
4975(e)(7) of the Code and the accompanying regulations, and Section 407(d)(6)
of ERISA. As provided below, the ESOP is designed to invest primarily in
qualifying employer securities of MCN Energy Group Inc..

         15.1 Redesignation of ESOP Portion of Plan. Effective as of the
effective date described in the preamble to this Article XV JANUARY 1, 1998, the
ESOP portion of the Plan shall consist of the ESOP Account of each Participant
plus the remaining part of each Participant's Plan Account that is invested in
the MCN Stock Fund. The put option provisions of Section 13.6 shall apply to the
entire ESOP portion of the Plan. However, only a Participant's ESOP Account
shall be subject to the restrictions described in the first sentence of Section
6.3.

         15.2 Allocation of Investment Plan Account Balances to ESOP Portion of
Plan. All amounts contributed, transferred or designated as allocable to the
Investment Plan Account of any Participant shall be treated as part of the ESOP
portion of the Plan to the extent the Participant has directed the investment of
such amounts in the MCN Stock Fund in accordance with Article VI of the Plan.

         15.3 Distribution of Dividends on MCN Stock. At the direction of the
Company exercised in its sole discretion, the Trustee will, after dividends are
paid on MCN Stock held in the Trust, but in no event later than 90 days
following the end of the Plan Year in which such dividends are paid (to the
extent such dividends are not used to make payment on an exempt loan as provided
for in section 13.4(c) of the Plan), either (i) distribute to Participants such
portion of the dividends attributable to the interests in MCN Stock held in
their Plan Accounts (or, if so determined by the Company, their ESOP Accounts)
as described below or, (ii) arrange to have such dividends distributed directly
to Participants by the Employer, or (iii) arrange to have such dividends
distributed to Participants by a dividend disbursement agent selected by the
Company. In its sole discretion, the Company may direct the Trustee to have such
dividends distributed only to Participants who elect (or fail not to elect) to
receive such dividend distributions in accordance with forms and procedures
established by the Company (which such procedures may apply to all Participants,
or solely to a group or groups determined by the Company). Further, in its sole
discretion, the Company may establish procedures that would permit Participants
to elect to have dividends distributed to them in a single sum rather


                                       49
<PAGE>   56


than over periods that might otherwise be determined by the Company to
correspond with Employer payroll practices.

         The distribution of dividends on MCN Stock held in a Participant's Plan
Account (or, if so determined by the Company, a Participant's ESOP Account)
shall be in an amount equal to all of the dividends paid on the MCN Stock held
in such Participant's Plan Account (or, if so determined by the Company, a
Participant's ESOP Account).



                               * * * * * * * * * *




                                       50
<PAGE>   57




         IN WITNESS WHEREOF, Michigan Consolidated Gas Company has caused its
corporate name to be hereunto affixed by its duly authorized officers as of the
29th day of December, 1998.


                                             MICHIGAN CONSOLIDATED GAS COMPANY



                                             By /s/ D. Nowokowski
                                                --------------------------------

                                             Its: VP,Human Resources
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