Nicor Inc.
                                                                        Form S-8
                                                                    Exhibit 4.02












                         NICOR COMPANIES
                    SAVINGS INVESTMENT PLAN
                (As Amended and Restated Effective
          as of January 1, 2001 Through Fifth Amendment)

























                            Mayer, Brown, Rowe & Maw
                                     Chicago



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                          NORTHERN ILLINOIS GAS COMPANY

                                   Certificate


      I, Alexander Allison, Assistant Secretary and Attorney of NORTHERN
ILLINOIS GAS COMPANY (doing business as Nicor Gas Company), having in my custody
and possession the corporate records and seal of said corporation, do hereby
certify that attached hereto is a true and correct copy of NICOR COMPANIES
SAVINGS INVESTMENT PLAN, as amended and restated effective as of January 1,
2001.

      WITNESS my hand and the corporate seal of the corporation this 25 day of
February, 2002.


                               /s/ Alexander C. Allison
                               ------------------------
                                   As Aforesaid
                                      (Seal)

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        ACTIONS OF OFFICER OF NORTHERN ILLINOIS GAS COMPANY
        ---------------------------------------------------

   WHEREAS, Northern Illinois Gas Company (doing business as Nicor Gas Company)
(the "Company") maintains Nicor Companies Savings Investment Plan (previously
known as Nicor Gas Savings Investment Plan (the "SIP")), Nicor Gas Thrift Plan
(the "Thrift Plan"), Nicor Companies Retirement Plan (previously known as the
Nicor Gas Retirement Plan (the "Retirement Plan")) and Nicor Gas Pension Plan
(the "Pension Plan");

   WHEREAS, certain amendments to the SIP, Thrift Plan, Retirement Plan and
Pension Plan were considered desirable to reflect changes in law and
administration;

   NOW, THEREFORE, pursuant to the authority granted to the officers of the
Company by action of its Board of Directors adopted on March 10, 1982, the SIP,
as amended and restated effective as of January 1, 2001, the Thrift Plan, as
amended and restated effective as of January 1, 2001, the Retirement Plan, as
amended and restated effective as of January 1, 2001, and the Pension Plan, as
amended and restated effective as of January 1, 2001, are each hereby adopted in
the forms attached hereto.



Date:  February 25, 2002            NORTHERN ILLINOIS GAS COMPANY

                                    By:  Claudia J. Collalillo

                                    Its:  Vice President Human Resources and
                                          Corporate Communications


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                                TABLE OF CONTENTS

SECTION 1    General..............................................1

      1.1. History, Purpose and Effective Date....................1

      1.2. Plan Administration, Trust Agreement...................1

      1.3. Plan Year..............................................1

      1.4. Applicable Laws........................................1

      1.5. Form of Election.......................................2

      1.6. Gender and Number......................................2

      1.7. Notices................................................2

      1.8. Evidence...............................................2

      1.9. Action by Employers....................................2

      1.10.Accounting Date........................................2

      1.11.Affiliate..............................................2

      1.12.Plan Supplements.......................................2

      1.13.Profit Sharing Plan and ESOP...........................2

SECTION 2    Participation........................................3

      2.1. Participants...........................................3

      2.2. Participation Not Contract of Employment...............3

      2.3. Restricted Participation...............................3

      2.4. Leased Employees.......................................4

      2.5. Compliance with Veterans' Laws.........................4

SECTION 3    Periods of Service...................................5

      3.1. Year of Service........................................5

      3.2. One Year Break in Service..............................5

SECTION 4    Plan Contributions...................................6

      4.1. Employee Tax-deferred Contributions....................6

      4.2. Employee After-tax Contributions.......................6

      4.3. Employer Matched Contributions.........................6

      4.4. Employer Profit Sharing Contributions..................7

      4.5. Compensation...........................................7

      4.6. Election to Vary or Suspend Contributions..............7

      4.7. Automatic Suspension of and Limitation on
           Contributions..........................................8

      4.8. Limitations on Contributions...........................8

      4.9. Reduction for Forfeitures..............................8

      4.10.Payment of Contributions...............................8

      4.11.Rollover Contributions.................................9

      4.12.Transfers From Thrift Plan.............................9

SECTION 5    Participants' Accounts...............................9

SECTION 6 The Trust Fund, Investment Fundsand Investment
             Elections ..........................................11

      6.1. The Investment Funds..................................11

      6.2. Investment Elections..................................11

      6.3. Transfers Among Investment Funds......................12

SECTION 7    Plan Accounting.....................................12

      7.1. Adjustment of Investment Funds........................13

      7.2. Deduction, Crediting and Allocation of
           Contributions.........................................13

      7.3. Statement of Plan Interest............................13

SECTION 8    Limitation On Amount Credited to Participants.......13

      8.1. Reduction of Contribution Rates.......................14

      8.2. Compensation for Limitation/Testing Purposes..........14

      8.3. Limitations on Annual Additions.......................14

      8.4. Adjustment For Related Defined Contribution Plans.....15

      8.5. Reduction of Contributions............................15

      8.6. Disposition of Excess Annual Additions................16

      8.7. Allocation Among Employers............................16

      8.8. Limitations Under Code Section 402(g).................17

      8.9. Code Section 401(k)(3) Testing........................17

      8.10.Correction of Section 401(k) Excess...................18

      8.11.Code Section 401(m)(2) Testing........................19

      8.12.Correction of Section 401(m) Excess...................20

      8.13.Multiple Use of Alternative Limitation................21

      8.14.Highly Compensated Employee...........................21

      8.15.Separate Testing of ESOP and Non-ESOP Portion of
           the Plan..............................................21

SECTION 9    Termination Dates...................................23

SECTION 10   Distributions.......................................23

      10.1.Fully Vested Benefits.................................23

      10.2.Benefits on Non-Vested Resignation or Dismissal.......23

      10.3.Restoration of Forfeitures............................24

      10.4.Manner of Payment.....................................25

      10.5.Payment in and Waiver of Joint and Survivor
           Annuity Form and Single Life Annuity Form.............25

      10.6.Payment in Form of Pre-Retirement Surviving Spouse
           Annuity...............................................26

      10.7.Election Information..................................26

      10.8.Commencement of Benefits..............................27

      10.9.Compliance With Section 401(a)(9) of the Code.........29

      10.10.Assets to be Distributed.............................29

      10.11.Designation of Beneficiary...........................29

      10.12.Interests Not Transferable...........................30

      10.13.Application of Forfeitures...........................31

      10.14.Distributions to Persons Under Disability............31

      10.15.Absence of Guaranty..................................31

      10.16.Missing Participants or Beneficiaries................31

      10.17.Spousal Consent......................................31

      10.18.Distribution and Withdrawal Elections................32

      10.19.Direct Rollover to an Eligible Retirement Plan.......33

      10.20.Distribution Only Upon Separation From Service.......33

      10.21.Transfers to Thrift Plan.............................33

SECTION 11   Withdrawals and Loans...............................34

      11.1.Pre-Termination Withdrawals From Employee
           After-tax Account.....................................34

      11.2.Pre-Termination Withdrawals From Employee
           Tax-deferred Account..................................34

      11.3.Hardship..............................................34

      11.4.Loans.................................................35

      11.5.Partial Withdrawals...................................37

      11.6.Order of Pre-Termination Withdrawals From Accounts....38

      11.7.Order of Post-Termination Withdrawals From Accounts...38

      11.8.Order of Withdrawal From Investment Funds.............38

      11.9.No Make-up of Withdrawals.............................38

SECTION 12   Nicor Stock.........................................39

      12.1.Purchase of Nicor Stock...............................39

      12.2.Voting Nicor Stock....................................39

SECTION 13   The Committee.......................................39

      13.1.Membership............................................39

      13.2.Rights, Powers and Duties.............................39

      13.3.Information to be Furnished to Committee..............40

      13.4.Committee's Decision Final............................40

      13.5.Remuneration and Expenses.............................40

      13.6.Indemnification of the Committee......................40

      13.7.Exercise of Committee's Duties........................40

      13.8.Resignation or Removal of Committee Member............41

      13.9.Appointment of Successor Committee Members............41

      13.10.Interested Committee Member..........................41

SECTION 14   Amendment and Termination...........................41

      14.1.Amendment.............................................41

      14.2.Termination...........................................41

      14.3.Merger and Consolidation of Plan, Transfer of Plan
           Assets................................................42

      14.4.Vesting and Distribution on Termination and
           Partial Termination...................................42

      14.5.Notice of Amendment, Termination or Partial
           Termination...........................................42


SUPPLEMENT A....................................................A-1
SUPPLEMENT B....................................................B-1

FIRST AMENDMENT OF NICOR COMPANIES SAVINGS INVESTMENT PLAN
SECOND AMENDMENT OF NICOR COMPANIES SAVINGS INVESTMENT PLAN
THIRD AMENDMENT OF NICOR COMPANIES SAVINGS INVESTMENT PLAN
FOURTH AMENDMENT OF NICOR COMPANIES SAVINGS INVESTEMENT PLAN
FIFTH AMENDMENT OF NICOR COMPANIES SAVINGS INVESTMENT PLAN

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                 NICOR COMPANIES SAVINGS INVESTMENT PLAN
                  (As Amended and Restated Effective
                         as of January 1, 2001)

SECTION 1.

                                     General

1.1. History, Purpose and Effective Date. Northern Illinois Gas Company (doing
business as Nicor Gas Company (the "company")) previously established the NI-Gas
SAVINGS INVESTMENT PLAN (the "plan") to promote the mutual interest of the
employers (as defined below) and their eligible employees by providing such
employees with an opportunity to supplement their retirement income through a
systematic savings program and to acquire an equity interest in the company's
business, and by providing the employers and their eligible employees with the
tax and other benefits provided under applicable laws to employee stock
ownership plans. Effective as of January 1, 2001, the name of the plan was
changed to "Nicor Companies Savings Investment Plan". The following provisions
constitute an amendment, restatement and continuation of the plan as in effect
immediately prior to January 1, 2001, the "effective date" of the plan as set
forth herein. The company and any affiliate (as defined in subsection 1.11)
which, with the consent of the company, adopts the plan are sometimes referred
to below collectively as the "employers" and individually as an "employer." The
plan is intended to qualify as a profit-sharing plan under section 401(a) of the
Internal Revenue Code of 1986, as amended (the "code") and as a qualified cash
or deferred arrangement under section 401(k) of the code.

1.2. Plan Administration, Trust Agreement. The authority to control and manage
the operation and administration of the plan shall continue to be vested in a
committee as described in Section 13. Except as otherwise specifically provided
in Section 13, the company shall have the rights, duties and obligations of the
plan "administrator" as described in section 3(16)(A) of the Employee Retirement
Income Security Act of 1974, as amended ("ERISA") and of a "plan administrator"
as that term is defined in section 414(g) of the code. The funds contributed by
the employers and participants under the plan will continue to be held and
invested until distributed by a trustee (the "trustee") acting under a trust
which forms a part of the plan. The terms of the trust are set forth in a trust
agreement known as Nicor Gas Savings Investment and Thrift Trust between the
trustee and the company. On and after the effective date, the company may
appoint an additional trustee or trustees to hold and invest any portion of the
trust fund in accordance with the provisions of other trust agreements which,
when executed, will form a part of the plan. Copies of the trust agreement and
the plan are filed at the general office of each employer where they may be
examined by any eligible employee or participant. The provisions of and benefits
under the plan are subject to the terms and provisions of the trust agreement.

1.3. Plan Year. The term "plan year" means the calendar year.

1.4. Applicable Laws. The laws of Illinois shall be the controlling state law in
all matters relating to the plan and shall be applicable to the extent that they
are not preempted by the laws of the United States of America.

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1.5. Form of Election. Each election, request or direction permitted to be made
by any participant or other person entitled to benefits under the plan, and any
permitted modification or revocation thereof, shall be filed with the committee
in such form and at such times as the committee may require.

1.6. Gender and Number. Where the context admits, words in any gender shall
include any other gender, words in the plural shall include the singular, and
words in the singular shall include the plural.

1.7. Notices. Notices and documents relating to the plan to be filed with the
committee may be delivered, or mailed by registered mail, postage prepaid, to
the committee, in care of the company, at its principal administrative office.
Any notice required under the plan may be waived by the person entitled to
notice.

1.8. Evidence. Evidence required of anyone under the plan may be by certificate,
affidavit, document or other information which the person acting on it considers
pertinent and reliable, and signed, made or presented by the proper party or
parties.

1.9. Action by Employers. Any action required or permitted to be taken by any
employer that is a corporation shall be by resolution of its board of directors,
or by a duly authorized officer of the employer. Any action required or
permitted to be taken by any employer that is a partnership shall be by a
general partner of such partnership or by a duly authorized officer thereof.

1.10. Accounting Date. The term "accounting date" means each business day.

1.11. Affiliate. The term "affiliate" means any corporation, trade or business
during any period that it is, along with any employer, a member of a controlled
group of corporations or a controlled group of trades or businesses (as
described in sections 414(b) and (c), respectively, of the code).

1.12. Plan Supplements. The provisions of the plan as applied to an employer or
to any group of employees of any employer may, with the consent of the company,
be modified or supplemented from time to time by the adoption of one or more
supplements. Each supplement shall form a part of the plan as of the
supplement's effective date. In the event of any inconsistency between a
supplement and the plan document, the terms of the supplement shall govern.

1.13. Profit Sharing Plan and ESOP. The plan shall consist of a profit sharing
plan which is intended to qualify under section 401(a) of the code (referred to
herein as the "non-ESOP portion of the plan"), and an employee stock ownership
plan (referred to herein as the "ESOP") which is intended to qualify as a stock
bonus plan under section 401(a) of the code and as an employee stock ownership
plan under section 4975(e)(7) of the code. The ESOP shall consist of the portion
of the plan which, as of that date, is invested in the Nicor Stock Fund
described in Section 6. The assets of the ESOP shall be invested primarily in
shares of the common stock of Nicor Inc. ("Nicor stock") which qualify as
employer securities within the meaning of section 409(l) of the code. Both the
ESOP and the non-ESOP portion of the plan include a qualified cash or deferred
arrangement within the meaning of section 401(k) of the

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code and the non-ESOP portion of the plan also consists of a profit sharing
component which is not a cash or deferred arrangement. Both the ESOP and the
non-ESOP portion of the plan are intended to constitute a single plan under
Treas. Reg. Section 1.414(l)-1(b)(1).

SECTION 2.

                                  Participation

2.1.       Participants. Each employee of the employers who was a "participant"
           in the plan as of December 31, 2000 will continue as such on and
           after January 1, 2001, subject to the conditions and limitations of
           the plan. Subject to the conditions and limitations of the plan, each
           other employee of the employers will become a "participant" in the
           plan on January 1, 2001 or the first day of the first pay period
           thereafter on which he meets the following requirements:

(a)        he has attained age 18 years; and

(b)        he is employed as a member of a group of employees to which
           the plan has been and continues to be extended, either
           by the unilateral action of his employer in the case of
           an employee who is not covered by a collective
           bargaining agreement or through a currently effective
           collective bargaining agreement between his employer
           and the collective bargaining representative of the
           group of employees of which he is a member.

In addition, each employee of the employers who begins employment with an
employer or an affiliate on or after January 1, 1999, who satisfies the
requirements of paragraphs 2.1(a) and (b) and who completes at least one year of
service (as defined in subsection 3.1) will become a "participant" in the plan
with respect to employer profit sharing contributions (as described in
subsection 4.4) on the first day of the first pay period after he satisfies the
foregoing requirements. Individuals who are participants in the plan with
respect to employer profit sharing contributions are sometimes referred to
herein as "profit sharing participants". Notwithstanding any provision of the
plan to the contrary, individuals who are not treated as common law employees by
an employer on its payroll records are excluded from plan participation even if
it is later determined (whether by judicial or administrative action or
otherwise) that such individual is or was a common law employee of an employer.

2.2.       Participation Not Contract of Employment. The plan does not
           constitute a contract of employment, and participation in the plan
           will not give any employee the right to be retained in the employ of
           any employer or any right or claim to any benefit under the terms of
           the plan unless such right or claim has specifically accrued under
           the terms of the plan.

2.3.       Restricted Participation. When distribution of part or all of the
           benefits to which a participant is entitled under the plan is
           deferred beyond or cannot be made until after his termination date
           (as described in Section 9), or, subject to the provisions of
           subsection 10.21, during any period that a participant continues in
           the employ of an employer or an affiliate but fails to meet the
           requirements of paragraph 2.1(b), or during any period for which
           employee tax-deferred contributions (as described in subsection 4.1),
           employee after-tax contributions (as described in subsection 4.2) or
           employer profit sharing contributions are not made with respect

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           to the participant, the participant, or in the event of his death,
           his beneficiary, will be considered and treated as a participant for
           all purposes of the plan except as follows:

(a)        no contributions will be credited to his accounts (as described in
           Section 5) for any period that the participant continues in the
           employ of the employers but fails to meet the requirements of
           paragraph 2.1(b) or after his termination date;

(b)        if a participant has elected distribution of his account balance in a
           lump sum, his accounts shall not be adjusted in accordance with the
           provisions of subsection 7.1 after his distribution date (as defined
           in subsection 10.1); and

(c)        a participant whose termination date has occurred and whose account
           balances have not yet been distributed may not make a withdrawal in
           accordance with the provisions of Section 11 except as otherwise
           specifically provided in subsection 11.5.

2.4.       Leased Employees. If, pursuant to one or more agreements between an
           employer or affiliate and one or more leasing organizations (within
           the meaning of section 414(n) of the code), a person provides
           services to the employer or affiliate, in a capacity other than as an
           employee, on a substantially full-time basis for a period of at least
           one year and such services are performed under the primary direction
           or control of an employer or affiliate, such person shall be a
           "leased employee". Leased employees shall not be eligible to
           participate in this plan or in any other plan maintained by the
           employer or affiliate which is qualified under section 401(a) of the
           code. A leased employee shall be treated as if the services performed
           by him in such capacity (including service performed during such
           initial one-year period) were performed by him as an employee of an
           affiliate which has not adopted the plan; provided, however, that no
           such service shall be credited:

(a)        for any period during which not more than 20% of the
           non-highly compensated workforce of the employers and
           the affiliates consists of leased employees and the
           leased employee is a participant in a money purchase
           pension plan maintained by the leasing organization
           which (i) provides for a nonintegrated employer
           contribution of at least 10 percent of compensation,
           (ii) provides for full and immediate vesting, and (iii)
           covers all employees of the leasing organization
           (beginning with the date they become employees), other
           than those employees excluded under section 414(n)(5)
           of the code; or

(b)        for any other period unless the leased employee provides satisfactory
           evidence to the employer or affiliate that he meets all of the
           conditions of this subsection 2.4 and applicable law required for
           treatment as a leased employee.

For purposes of paragraph (a) above, "highly compensated" shall have the meaning
set forth in subsection 8.14.

2.5. Compliance with Veterans' Laws. Notwithstanding any other provision of this
plan to the contrary, for reemployments occurring on or after December 12, 1994,
contributions, benefits and service credit with respect to qualified military
service will be provided in accordance with section 414(u) of the code.

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SECTION 3.

                               Periods of Service

3.1.       Year of Service. An employee's or participant's years of service as
           at any date equals the year or years and any portion thereof elapsed
           since his initial date of hire by an employer or affiliate subject to
           the following:

(a)        An employee's or participant's number of years of service, and
           portion thereof, for the period prior to the effective date shall be
           equal to his number of years of service, and any portion thereof, if
           any, determined under the provisions of the plan as in effect on
           December 31, 2000.

(b)        If an employee's or participant's employment with the employers and
           affiliates is terminated and he incurs a one year break in service
           (as defined in subsection 3.2), he shall not be credited with service
           for the period between the date of his termination and the date, if
           any, of his reemployment by any employer or affiliate.

(c)        For purposes of determining whether a participant has a
           nonforfeitable interest in his employer contribution
           subaccounts (as defined in Section 5) accrued prior to
           the date he incurs five consecutive one year breaks in
           service (or prior to the date he incurs a one year
           break in service, if it is incurred before January 1,
           1985), a participant's number of years of service
           accrued after such five consecutive one year breaks in
           service (or, if the break in service was incurred
           before January 1, 1985, such one year break in service)
           shall be disregarded.

3.2.       One Year Break in Service. The term "one year break in service"
           means, with respect to any employee or participant, the
           12-consecutive-month period commencing on the date of his termination
           of employment with the employers and affiliates if he is not
           reemployed by an employer or affiliate during that period.
           Notwithstanding the preceding sentence, solely for purposes of
           determining whether a one year break in service has occurred, an
           employee or participant who is absent from service on account of a
           maternity or paternity absence (as defined below) that extends beyond
           the first anniversary of the date such absence began shall be deemed
           to have terminated employment with the employers and affiliates on
           the later of (i) his termination date, or (ii) the second anniversary
           of the date on which such absence began. The term "maternity or
           paternity absence" means an employee's or participant's absence from
           work that commences on or after January 1, 1985 because of the
           pregnancy of the individual, the birth of a child of the individual,
           the placement of a child with the individual in connection with the
           adoption of a child by such individual, or for purposes of caring for
           the child by such person immediately following such birth or
           placement. The committee may require the individual to furnish such
           information as the committee considers necessary to establish that
           the individual's absence was for one of the reasons specified above.

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SECTION 4.

                               Plan Contributions

4.1.       Employee Tax-deferred Contributions. Subject to the following
           provisions of this Section 4 and Section 8, each employer, out of its
           current or accumulated profits (as determined in accordance with
           recognized accounting principles and practices), shall contribute to
           the trustee, in cash, on behalf of each participant for whom a tax
           deferral election is in effect as to any pay period, an amount,
           referred to herein as an "employee tax-deferred contribution", which
           is equal to the amount by which the compensation (as defined in
           subsection 4.5) otherwise payable to the participant during that pay
           period by the employer has been reduced pursuant to the terms of a
           tax deferral election. For purposes of the plan, the term "tax
           deferral election" means an election by an employee to have the
           amount of the compensation that would otherwise be payable to him for
           each pay period during the period in which the election is in effect
           reduced by an amount that is not less than 1 percent and not more
           than 12 percent (or such other percent as the committee shall decide
           and, in all cases, in multiples of one percent). The plan provisions
           relating to certain limitations on employee after-tax contributions
           are set forth in subsection 4.2. Employee tax-deferred contributions
           shall be paid to the trustee in accordance with subsection 4.10.

4.2.       Employee After-tax Contributions. Subject to the following provisions
           of this Section 4 and Section 8, a participant may elect to
           contribute for any pay period, in cash, an amount, hereafter referred
           to as an "employee after-tax contribution", that is not less than l
           percent and not more than 7 percent of his compensation for that pay
           period (or such other percent as the committee shall decide and, in
           all cases, in multiples of one percent). The plan provisions relating
           to certain limitations on employee tax-deferred contributions are set
           forth in subsection 4.1. A participant's employee after-tax
           contributions, if any, shall be made by regular payroll deductions
           from his compensation and shall be paid to the trustee in accordance
           with subsection 4.10.

4.3.       Employer Matched Contributions. Subject to the following provisions
           of this Section 4 and Section 8, each employer, other than Nicor Home
           Services, Inc. ("NHS"), out of its current or accumulated profits (as
           determined in accordance with recognized accounting principles and
           practices), shall contribute to the trustee, in cash, on behalf of
           each participant for whom a tax deferral election is in effect for
           any pay period or who has elected to make employee after-tax
           contributions for any pay period, an amount, referred to herein as an
           "employer matched contribution", equal to:

(a)        100 percent of the employee tax-deferred contributions and employee
           after-tax contributions made by or on behalf of the participant for
           that pay period that do not exceed 3 percent of the participant's
           compensation for that pay period; plus

(b)        75 percent of the employee tax-deferred contributions and employee
           after-tax contributions made by or on behalf of the participant for
           that pay period that exceed 3 percent of the participant's
           compensation for the pay period but which do not exceed 6 percent of
           the participant's compensation for that pay period.

                                        6
<PAGE>

Subject to the following provisions of this Section 4 and Section 8, NHS, out of
its current or accumulated profits (as determined in accordance with recognized
accounting principles and practices), shall contribute to the trustee, in cash,
on behalf of each participant who is employed by NHS for any pay period and for
whom a tax deferral election is in effect for such pay period or who has elected
to make employee after-tax contributions for such pay period, an amount,
referred to herein as an "employer matched contribution", equal to 50 percent of
the employee tax-deferred contributions and employee after-tax contributions
made by or on behalf of the participant for that pay period that do not exceed 6
percent of the participant's compensation for that pay period. Notwithstanding
any other provision of the plan, employer matched contributions shall first be
made with respect to employee tax-deferred contributions before any employer
matched contributions are made with respect to employee after-tax contributions.
Employer matched contributions shall be paid to the trustee in accordance with
subsection 4.10.

4.4.       Employer Profit Sharing Contributions. Subject to the following
           provisions of this Section 4 and Section 8, the company, out of its
           current or accumulated profits, shall make an "employer profit
           sharing contribution" to the plan for each plan year in an amount, if
           any, determined by the company in its sole discretion. Each other
           employer shall make an employer profit sharing contribution for the
           same plan year on behalf of each participant entitled to an
           allocation in accordance with subsection 7.2, in an amount equal to
           the contribution made by the company, expressed as a percentage of
           compensation. Employer profit sharing contributions shall be paid to
           the trustee in accordance with subsection 4.10 and shall be allocated
           to the accounts of profit sharing participants in accordance with
           subsection 7.2.

4.5.       Compensation. For purposes of the plan, a participant's
           "compensation" for any period means the regular basic cash
           remuneration paid to him for such period by reason of his employment
           with the employers as a participant, excluding bonuses, overtime pay,
           and all other remuneration of any kind including, but not limited to
           pre-paid salary increase advances and lump sum raise payments, and
           including vacation pay, reductions made in accordance with the
           provisions of subsection 4.1, reductions made pursuant to section 125
           of the code, including under any tax exempt premium plan in which the
           employee participates, and reductions made pursuant to section
           132(f)(4) of the code; provided, however, that the compensation of
           any participant for any plan year shall be disregarded to the extent
           that it exceeds $160,000 (adjusted in accordance with section
           401(a)(17) of the code), taking into account any proration of such
           amount as may be required under applicable Treasury regulations on
           account of a short plan year. Notwithstanding the foregoing, the
           "compensation" as applied to any participant who is employed by NHS
           shall mean, for any period prior to March 1, 2002, the total cash
           remuneration paid to him for such period by reason of his employment
           with NHS (not in excess of the limitations imposed by section
           401(a)(17) of the code), including reductions made in accordance with
           the provisions of subsection 4.1, reductions made pursuant to section
           125 of the code, including under any tax exempt premium plan in which
           the employee participates, and reductions made pursuant to section
           132(f)(4) of the code.

4.6.       Election to Vary or Suspend Contributions. A participant may elect to
           have his employer change the rate of employee tax-deferred
           contributions being made by that employer on his behalf, or elect to
           change his employee after-tax contribution rate in accordance with
           uniform rules established by the committee. A participant may elect
           to have his employer suspend employee tax-deferred contributions
           being made by that employer on his behalf, or may

                                        7
<PAGE>

           elect to suspend making his employee after-tax contributions, in
           accordance with uniform rules established by the committee.
           Notwithstanding the foregoing provisions of this subsection 4.6,
           no change to or suspension of contributions shall be applied
           retroactively and all changes to elections (including suspensions of
           contributions) shall be effective as soon as administratively
           feasible after the date elected by the participant.

4.7.       Automatic Suspension of and Limitation on Contributions. The
           provisions of the plan requiring the contribution of employee
           tax-deferred contributions under a tax deferral election by a
           participant, permitting a participant to make employee after-tax
           contributions or requiring an employer to make an employer profit
           sharing contribution on behalf of a profit sharing participant shall
           be without effect as to:

(a)        any period during which the participant fails to meet the
           requirements of paragraph 2.1(b); and

(b)        the amount of any employee tax-deferred contributions, employee
           after-tax contributions or employer profit sharing contributions
           otherwise payable to the plan on behalf of a participant which could
           not be credited to that participant's accounts because of the
           provisions of Section 8.

4.8.       Limitations on Contributions. In no event will an employer's employee
           tax-deferred contributions, employer matched contributions and
           employer profit sharing contributions under the plan for any plan
           year exceed an amount equal to the lesser of (a) the maximum amount
           deductible on account thereof by the employer for that plan year as
           an expense for federal income tax purposes, after taking into account
           amounts contributed in accordance with subsection 10.3, or (b) the
           amount that, together with any forfeitures arising under the plan
           during the year which are attributable to that employer's
           contributions, can be credited for that plan year in accordance with
           Section 8.

4.9.       Reduction for Forfeitures. Forfeitures arising under the plan which
           are attributable to prior contributions by an employer shall be
           considered contributions to the plan by that employer and shall be
           applied to reduce the amount of contributions otherwise required by
           that employer under this Section 4.

4.10.      Payment of Contributions. The employee tax-deferred contributions and
           employee after-tax contributions with respect to any participant
           shall be paid to the trustee by the employers on the earliest date on
           which such contributions can reasonably be segregated from the
           employers' general assets, which date shall be no later than the 15th
           business day of the month following the month (a) in which such
           amounts are received by the employer (in the case of amounts paid to
           an employer by a participant), or (b) such amounts would otherwise
           have been payable to the participant (in the case of amounts withheld
           by an employer from a participant's wages), or, in either case, such
           other date permitted by law. Each employer's employer matched
           contributions and employer profit sharing contributions under the
           plan for any plan year shall be paid to the trustee, without
           interest, no later than the time prescribed by law for filing the
           employer's federal income tax return, including any extensions
           thereof.

                                        8
<PAGE>

4.11.      Rollover Contributions. An employee who satisfies the requirements of
           subsection 2.1 of the plan and who is actively employed by an
           employer and any participant who is actively employed by an employer
           or an affiliate may, with the consent of the committee, make a
           rollover contribution (as defined below) to the trustee of the plan.
           The term "rollover contribution" means:

(a)        a cash contribution to the plan by the participant of amounts
           distributed from a qualified plan described in section 401(a) of the
           code (or distributed from an individual retirement account and
           constituting a "rollover contribution" as described in section
           408(d)(3) of the code) and made within 60 days of receipt of such
           amount; or

(b)        a cash payment made to the plan by another qualified plan described
           in section 401(a) of the code as a direct rollover (as contemplated
           by section 401(a)(31) of the code) on behalf of and at the direction
           of the participant,

provided such distributed or directly rolled over amounts are permitted to be
rolled over to a qualified plan under the applicable provisions of the code as
then in effect. The committee may request from the participant such documents as
it considers necessary or desirable to establish that the rollover contribution
satisfies the foregoing requirements. The portion of a participant's interest
under the plan which is attributable to his rollover contributions shall be
fully vested and nonforfeitable at all times. An employee who has made a
rollover contribution but who is not a participant in the plan will be treated
as a participant solely with respect to the amounts credited to his rollover
account under the plan (as described in Section 5).

4.12.      Transfers From Thrift Plan. If an employee of an employer ceases to
           satisfy the eligibility requirements of the Nicor Gas Thrift Plan
           (the "thrift plan") because he is no longer employed as a member of a
           group of employees to which the thrift plan has been extended and
           continues to be extended through a currently effective collective
           bargaining agreement between his employer and the collective
           bargaining representative of the group of employees of which he is a
           member and the employee:

(a)        continues to be employed by an employer or an affiliate; and

(b)        coincident with his cessation of eligibility for the thrift plan, he
           satisfies the provisions of subsection 2.1 of the plan;

then his account balances under the thrift plan, determined as of the accounting
date coincident with or next following the date described in paragraph (a) next
above, shall be transferred as soon as practicable thereafter to the
corresponding accounts under the plan and, for periods thereafter, he shall
cease to be a participant in the thrift plan and shall be a participant in this
plan, subject to the terms and conditions of the plan. Amounts transferred to
the plan pursuant to this subsection 4.12 shall not be considered annual
additions for purposes of Section 8.

SECTION 5.

                             Participants' Accounts

                                        9
<PAGE>

      The committee will maintain the following accounts, which accounts shall
be adjusted from time to time as required by subsection 7.1:

(a)   An "employee tax-deferred account" in the name of each
      participant for whom employee tax-deferred
      contributions or employer matched contributions
      attributable thereto, were made under the plan or for
      whom amounts were transferred to the plan from his
      employee tax-deferred account under the thrift plan,
      which account will consist of the following three
      subaccounts, to the extent applicable:

      (i)   a subaccount known as the "employee tax-deferred
            contribution subaccount", which subaccount shall
            reflect the amount of the employee tax-deferred
            contributions made by the employers on his behalf,
            and amounts transferred from his employee
            tax-deferred contribution subaccount under the
            thrift plan, and the income, losses, appreciation
            and depreciation attributable thereto;

     (ii)  a subaccount known as the "tax-deferred employer matched contribution
           subaccount", which subaccount shall reflect the amount of the
           employer matched contributions made by the employers on his behalf
           under the plan which are attributable to his employee tax-deferred
           contributions and amounts transferred from his tax-deferred employer
           matched contribution subaccount under the thrift plan, and the
           income, losses, appreciation and depreciation attributable thereto;
           and

    (iii)  a subaccount known as the "rollover account", which subaccount shall
           reflect the amount of rollover contributions made by the participant
           under the plan, and the income, losses, appreciation and depreciation
           attributable thereto.

(b)   An "employee after-tax account" in the name of each
      participant who made employee after-tax contributions
      under the plan or for whom employer matched
      contributions attributable thereto were made under the
      plan or for whom amounts were transferred to the plan
      from his employee after-tax account under the thrift
      plan, which account will consist of the following two
      subaccounts, to the extent applicable:

     (i)   a subaccount known as the "employee after-tax contribution
           subaccount", which subaccount will reflect the
           amount of the employee after-tax contributions
           made by the participant in accordance with the
           terms of the plan and amounts transferred from his
           employee after-tax contribution subaccount under
           the thrift plan, and the income, losses,
           appreciation and depreciation attributable
           thereto; and

    (ii)   a subaccount known as the "employee after-tax employer matched
           contribution subaccount", which subaccount will reflect the amount of
           the employer matched contributions made by the employer in accordance
           with

                                        10
<PAGE>

           the terms of the plan that are attributable to his employee
           after-tax contributions and amounts transferred from his employee
           after-tax employer matched contribution subaccount under the thrift
           plan, and the income, losses, appreciation and depreciation
           attributable thereto.

(c)   A "profit sharing account" in the name of each profit sharing
      participant, which account shall reflect his share of employer profit
      sharing contributions, and the income, losses, appreciation and
      depreciation attributable thereto.

Reference to a participant's "accounts" means his employee tax-deferred account,
his employee after-tax account and his employer profit sharing account.
Reference to the "balance" in any account maintained in the name of a
participant means the aggregate of the balances in the investment funds (as
described in subsection 6.1) established for the investment of participants'
accounts. Reference to a participant's "employee contribution subaccounts" means
his employee tax-deferred contribution subaccount, his employee after-tax
contribution subaccount and his rollover subaccount and reference to a
participant's "employer contribution subaccounts" means his tax-deferred
employer matched contribution subaccount, his employee after-tax employer
matched contribution subaccount and his profit sharing account.

SECTION 6.

                       The Trust Fund, Investment Funds
                            and Investment Elections

6.1.   The Investment Funds. The committee may, from time to time, cause one
       or more "investment funds" to be established under the Trust for the
       investment of participants' accounts, which investment funds shall
       include:

(a)        a "Loan Fund" which shall consist only of loans to participants in
           accordance with subsection 11.4; and

(b)        a "Nicor Stock Fund" which shall be invested primarily in shares of
           common stock of Nicor Inc.

Unless a participant elects otherwise in accordance with subsection 6.2 or 6.3,
no change shall be made in the investment of a participant's accounts merely
because of a change or addition of investment funds. The committee may, from
time to time, eliminate or add investment funds or may make any changes to
investment funds as it deems appropriate. Pending more permanent investment of
available funds, or to accommodate cash flow needs, the trustee may retain any
reasonable portion of an investment fund in cash, short-term government
obligations or commercial paper.

6.2.   Investment Elections. Contributions made with respect to any
       participant and amounts transferred to the plan from the thrift plan
       on behalf of any participant shall be invested in accordance with the
       following provisions of this subsection 6.2:

(a)        Each participant may prospectively specify separately the percentages
           (in multiples of 1 percent or such other amount specified from time
           to time by the

                                        11
<PAGE>

           committee) of his tax-deferred, employee after-tax
           contributions and employer profit sharing contributions that are to
           be invested in each of the investment funds.

(b)        A participant may prospectively change his investment direction
           effective as of the first day of the first pay period or such other
           dates permitted by the committee.

(c)        The employer matched contributions that are made with respect to a
           participant and credited to his employee tax-deferred account shall
           be invested in the investment funds in the same direction as are his
           employee tax-deferred contributions.

(d)        The employer matched contributions that are made with respect to a
           participant and credited to his employee after-tax account shall be
           invested in the investment funds in the same proportions as are his
           employee after-tax contributions.

(e)        Amounts transferred to the plan from the thrift plan shall be
           invested in the same investment funds, in the same proportion, as
           such amounts were invested under the thrift plan immediately prior to
           the transfer.

(f)        An employee who is not a participant but who elects to make
           a rollover contribution to the plan in accordance with
           subsection 4.11 may prospectively specify the
           percentage (in multiples of 1 percent) of his rollover
           contributions that are to be invested in each of the
           investment funds. Rollover contributions that are made
           by a participant and credited to his employee
           tax-deferred account under the plan shall be invested
           in the investment funds in the same proportions as are
           his employee tax-deferred contributions.

(g)        During any period for which no direction as to the investment of a
           participant's contributions is on file with the committee,
           contributions by him or on his behalf under the plan will be invested
           in an investment fund specified by the committee.

(h)        Any amount held in a suspense account (as described in subsection
           8.6) shall be invested in an investment fund specified by the
           committee.

Elections pursuant to this subsection 6.2 shall be made in accordance with
uniform and nondiscriminatory rules established from time to time by the
committee.

6.3. Transfers Among Investment Funds. A participant (or a beneficiary to whom
benefits are being distributed in accordance with paragraph 10.4(b)) may
transfer his accounts between or among investment funds by giving such notice to
the trustee as the committee shall require, directing that all or a portion of
the value of his accounts attributable to a particular investment fund shall be
transferred to any of the other available investment funds. A transfer shall be
effective pursuant to uniform and nondiscriminatory rules established from time
to time by the committee.

SECTION 7.

                                 Plan Accounting

                                        12
<PAGE>

7.1.       Adjustment of Investment Funds. The value of any investment held
           under or distributed from the plan as of any date shall be the fair
           market value (as determined by the trustee) of the investment on that
           date, or as of the most recent prior date on which it was valued by
           the trustee. The trustee shall value an investment held under the
           plan in accordance with rules established by it provided that all
           investments under the plan on the last day of each plan year shall be
           valued by the trustee as of that date.

7.2.       Deduction, Crediting and Allocation of Contributions. Subject to the
           provisions of Section 8:

(a)        Employee tax-deferred contributions, employee after-tax contributions
           and rollover contributions on behalf of a participant for any period
           shall be credited to that participant's appropriate accounts as of
           the day on which such contributions are made.

(b)        The amount of the employer matched contributions that are
           made on behalf of a participant shall be credited, as
           of the end of the day that the contributions are made,
           to the participant's employee tax-deferred account and
           employee after-tax account, pro rata, according to the
           rate of employee tax-deferred contributions and
           employee after-tax contributions that are made with
           respect to the participant, respectively; provided,
           however, that, if the sum of a participant's employee
           tax-deferred contribution rate and employee after-tax
           contribution rate exceeds 6 percent of the
           participant's compensation, then the amount of the
           employer matched contributions made with respect to the
           participant shall be credited to the participant's
           employee tax-deferred account in the same ratio that
           the participant's employee tax-deferred contribution
           rate (not in excess of 6 percent) bears to 6 percent,
           and the amount of any remaining employer matched
           contributions shall be credited to the participant's
           employee after-tax account.

(c)        As of the last day of each plan year the employer profit sharing
           contributions of each employer for that plan year shall be allocated
           among and credited to the profit sharing accounts of profit sharing
           participants who were employed by the employer on the last day of the
           plan year, pro rata based on the compensation paid to them from the
           employer for that plan year.

For purposes of this Section 7, all employer contributions for any plan year
which are made after the close of the plan year will be considered to have been
made on the last day of that plan year regardless of when paid to the trustee.

7.3. Statement of Plan Interest. As soon as practicable after the last day of
each plan year, and at such other times as the committee may deem appropriate,
the committee shall provide each participant with a statement reflecting the
balances of his accounts.

SECTION 8.

                 Limitation On Amount Credited to Participants

                                        13
<PAGE>

8.1.       Reduction of Contribution Rates. To conform the operation of the plan
           to the requirements of sections 401(a)(4), 401(k)(3), 401(m)(2),
           402(g) and 415(c) of the code, the committee may unilaterally modify
           or revoke any tax deferral election made by any person, may limit the
           amount of contributions that may be made by or on behalf of any
           participant pursuant to Section 4 or may reduce (to zero if
           necessary) the level of employer matched contributions or employer
           profit sharing contributions to be made on behalf of any participant
           under the plan.

8.2.       Compensation for Limitation/Testing Purposes. For purposes of the
           plan, the term "section 415 compensation" for any plan year means the
           participant's compensation (as described in Treas. Reg. Section
           1.415-2(d)(1)) paid during that year for personal services actually
           rendered in the course of employment with any employer or any section
           415 affiliate, excluding deferred compensation and other amounts that
           receive special tax treatment (as described in Treas. Reg. Section
           1.415-2(d)(2)) but including any elective contributions made on the
           participant's behalf for the year under the plan or any plan
           maintained by an employer or affiliate which are excludable from the
           participant's gross income by reason of section 125, 402(e)(3) and
           132(f) of the code. Notwithstanding the foregoing provisions of this
           subsection 8.2, "section 415 compensation" for any plan year shall be
           disregarded to the extent that it exceeds $160,000 (adjusted in
           accordance with section 401(a)(17) of the code), taking into account
           any proration of such amount as may be required under applicable
           Treasury regulations where section 415 compensation is computed with
           respect to a period of less than a full year (other than on account
           of mid-year commencement or cessation of active participation in the
           plan).

8.3.       Limitations on Annual Additions. Notwithstanding any other provision
           of the plan other than the provisions of this Section 8, for plan
           years beginning on or after January 1, 1995, a participant's annual
           additions (as defined below) for any plan year shall not exceed an
           amount equal to the lesser of:

(a)        $30,000 (as adjusted for each plan year to take into account any
           applicable cost-of-living adjustment for that year provided by the
           Secretary of the Treasury under section 415(d) of the code); or

(b)        25 percent of the section 415 compensation paid to the participant in
           that plan year (determined without regard to the limitations of
           section 401(a)(17) of the code).

The limitations set forth under paragraphs (a) and (b) shall be adjusted to the
extent required by subsection 8.4. For purposes of the plan, the term "annual
additions" means, with respect to any participant for any plan year, the sum of
the following amounts, determined without regard to whether any such amounts (or
portions thereof) are subsequently distributed to the participant in accordance
with the provisions of subsection 8.8, 8.10, 8.12 or 8.13:

(1)        employer contributions and forfeitures (including employee
           tax-deferred contributions which are considered to be employer
           contributions) credited to the participant's accounts for that plan
           year under this plan and each related defined contribution plan (as
           defined below);
                                        14
<PAGE>

(2)        employee contributions (other than rollover contributions) credited
           to the participant's accounts under this plan and each related
           defined contribution plan for that plan year; and

(3)        employer contributions allocated to any individual medical account
           (as described in section 415(l) of the code) that is maintained for
           the benefit of the participant under a related defined benefit plan
           (as defined below) and, if the participant is a key employee (as
           defined in Supplement A), any amount allocated to a related medical
           account (as defined below) maintained for the participant; provided,
           however, that the amounts described in this paragraph (3) shall be
           disregarded for purposes of the limitation set forth in paragraph (b)
           next above.

For purposes of the plan: (i) the term "related medical account" means any
account maintained by any employer or section 415 affiliate under section
419A(d) of the code to fund retiree medical benefits; (ii) the term "section 415
affiliate" means any corporation or trade or business that is, along with any
employer, a member of a controlled group of corporations or controlled group of
trades or businesses (as described in sections 414(b) and (c) of the code, as
modified by section 415(h) thereof); and (iii) the term "related defined
contribution plan" and "related defined benefit plan" mean any other defined
contribution plan and any defined benefit plan (both as defined in section
415(k) of the code), respectively, maintained by any employer or section 415
affiliate.

8.4.       Adjustment For Related Defined Contribution Plans. During any plan
           year in which a participant is also a participant in any related
           defined contribution plan, the maximum annual additions attributable
           to employer contributions and forfeitures which could otherwise be
           credited to his accounts for the year under this plan in accordance
           with subsection 8.3 shall be reduced to a proportionate amount
           thereof determined by the ratio of the amount of employer
           contributions which would otherwise be credited to his accounts under
           this plan for the year to the total amount of employer contributions
           which would otherwise be credited to his accounts under this plan and
           all such related defined contribution plans for the year.

8.5.       Reduction of Contributions. In the event that a participant's annual
           additions for any plan year would otherwise exceed the limitations
           imposed by subsection 8.3, as modified by subsection 8.4, the amount
           of contributions that would otherwise be credited to his accounts for
           that year shall be reduced, to the extent necessary to comply with
           such limitations, in the following order:

(a)        first, employee after-tax contributions that would not otherwise
           result in employer matched contributions being made shall be reduced;

(b)        next, employee tax-deferred contributions that would not otherwise
           result in employer matched contributions being made shall be reduced;

(c)        next, employee after-tax contributions and the employer matched
           contributions to the extent attributable to those contributions shall
           be reduced;

(d)        next, employee tax-deferred contributions and the employer matched
           contributions to the extent attributable to those contributions shall
           be reduced; and

                                        15
<PAGE>

(e)        finally, employer profit sharing contributions shall be reduced.

The amount of any reduction made pursuant to this subsection 8.5 shall not be
considered an annual addition under the plan.

8.6.    Disposition of Excess Annual Additions. If, as a result of a
        reasonable error in estimating a participant's section 415
        compensation, a reasonable error in determining the amount of
        elective deferrals (as defined in section 402(g)(3) of the code) or
        as a result of such other circumstances as the Commissioner of
        Internal Revenue may determine, a participant's annual additions for
        a plan year would exceed the limitations set forth in subsection 8.3,
        as modified by subsection 8.4:

(a)   The amount of employee after-tax contributions made by a
      participant which may not be credited to the
      participant's accounts because of the foregoing
      provisions of this Section 8, together with earnings
      thereon, will be returned to the participant as soon as
      practicable.  Employee after-tax contributions for
      which no employer matched contributions were made shall
      be returned before employee after-tax contributions for
      which employer matched contributions were made.

(b)   The amount of employee tax-deferred contributions made on
      behalf of a participant which may not be credited to
      the participant's accounts because of the foregoing
      provisions of this Section 8, together with earnings
      thereon, will be returned to the participant as soon as
      practicable. Contributions which are to be returned
      pursuant to this paragraph (b) shall be returned in the
      following order: (i) employee tax-deferred
      contributions for which no employer matched
      contributions were made, and (ii) employee tax-deferred
      contributions for which employer matched contributions
      were made.

(c)   The amount of any employer matched contributions, employer profit
      sharing contributions and forfeitures attributable to an employer (as
      described in subsection 10.13) that may not be credited to
      participants' accounts for any plan year because of the foregoing
      provisions of this Section 8 will be treated in accordance with
      Treas. Reg. Section 1.415-6(b)(6)(i).

Amounts returned to a participant or credited to a suspense account in
accordance with this subsection 8.6 shall not be considered an annual addition
for purposes of the plan. If any employee after-tax contributions or employee
tax-deferred contributions are returned to a participant pursuant to this
subsection 8.6, the amount of any employer matched contributions attributable to
such returned contributions shall be forfeited and shall be treated in the same
manner as any other forfeiture under the plan.

8.7.       Allocation Among Employers. If the amount of employer contributions
           otherwise allocable to a participant in any plan year would exceed
           the limitations imposed by the provisions of subsection 8.3, as
           modified by subsection 8.4, and the participant is employed by more
           than one employer during that year, the amount of each employer's
           contributions and forfeitures attributable to the prior contributions
           of that employer which would otherwise be allocated and credited to
           the participant's accounts will be reduced (in accordance with

                                        16
<PAGE>

           subsection 8.5) by an amount determined by multiplying such excess
           amount by a fraction, the numerator of which is the sum of the
           employer's contributions and forfeitures attributable to the prior
           contributions of that employer otherwise allocable to the participant
           for that year, and the denominator of which is the sum of the
           contributions of all employers and forfeitures attributable to the
           prior contributions of all employers otherwise allocable to the
           participant for that year.

8.8.       Limitations Under Code Section 402(g). In no event shall the employee
           tax-deferred contributions made with respect to a participant for any
           taxable year under the plan (together with any elective deferrals, as
           defined in section 402(g)(3) of the code, made with respect to the
           participant for that year under any other plan maintained by an
           employer or affiliate) exceed $10,500 or such other amount as may be
           permitted for that year under section 402(g) of the code. If, during
           any taxable year, a participant is also a participant in another cash
           or deferred arrangement and his elective deferrals under such other
           arrangement, together with his employee tax-deferred contributions,
           exceed the maximum amount permitted for that year under section
           402(g) of the code, the participant, not later than March 1 following
           the close of such taxable year, may request the committee to
           distribute all or a portion of such excess to him, with the income
           allocable thereto (determined in accordance with Treas. Reg. Section
           1.402(g)-1(d)(5) using the safe harbor method for determining the
           allocable income for the period between the end of the taxable year
           and the date of distribution), and such distribution shall be made
           not later than April 15th following the close of such taxable year.
           The committee may demand adequate proof of the existence of such
           excess. In addition, if the applicable limitation for a plan year
           happens to be exceeded with respect to this plan alone, or this plan
           and another plan or plans of the employers and affiliates, the
           committee shall direct such excess employee tax-deferred
           contributions (with allocable gains or losses) to be distributed to
           the participant as soon as practicable after the committee is
           notified of the excess deferrals by the company, an employer or the
           participant, or otherwise discovers the error (but not later than the
           April 15 following the close of the participant's taxable year).
           Notwithstanding the foregoing provisions of this subsection 8.8, the
           dollar amount of any distribution due hereunder shall be reduced by
           the dollar amount of any employee tax-deferred contributions
           previously distributed to the same participant pursuant to subsection
           8.10; provided, however, that for purposes of subsections 8.3 and
           8.9, the correction under this subsection 8.8 shall be deemed to have
           occurred before the correction under subsection 8.10. Amounts
           distributed in accordance with this subsection 8.8 shall not be
           treated as annual additions for purposes of subsection 8.3.

8.9.       Code Section 401(k)(3) Testing. The difference between (i) the
           average of the deferral percentages (as defined below) of each
           eligible employee who is highly compensated for the plan year
           (referred to hereinafter as the "highly compensated group deferral
           percentage"), and (ii) the average of the deferral percentages for
           the immediately preceding plan year of each eligible employee who was
           not highly compensated for such preceding plan year (referred to
           hereinafter as the "non-highly compensated group deferral
           percentage") shall satisfy one of the tests set forth in section
           401(k)(3)(A)(ii) of the code. The "deferral percentage" for any
           eligible employee for a plan year shall be determined by dividing the
           amount of the employee tax-deferred contributions made with respect
           to the participant for such year by his section 415 compensation for
           the year, subject to the following special rules:

(a)        the deferral percentage of an eligible employee who makes no employee
           tax-deferred contributions for the year shall be counted as zero;

                                        17
<PAGE>

(b)        the deferral percentage for any eligible employee who is
           highly compensated and who is eligible to make elective
           deferrals under one or more other plans maintained by
           an employer or affiliate for a plan year of such other
           plan that ends with or within the same calendar year as
           the plan year (other than a plan or arrangement subject
           to mandatory disaggregation under applicable Treasury
           regulations) shall be determined as if all such
           elective deferrals were made on his behalf under the
           plan;

(c)        excess employee tax-deferred contributions distributed to a
           participant under subsection 8.8 shall be counted in determining such
           participant's deferral percentage except in the case of a
           distribution to a non-highly compensated participant required to
           comply with section 401(a)(30) of the code; and

(d)        in the event that this plan satisfies the requirements of
           sections 401(k), 401(a)(4), or 410(b) of the code only
           if aggregated with one or more other plans having the
           same plan year, or if one or more other plans having
           the same plan year as this plan satisfy the
           requirements of such sections of the code only if
           aggregated with this plan, then this subsection 8.9
           shall be applied as if all such plans were a single
           plan.

Application of this subsection 8.9 shall be consistent with the provisions of
section 401(k)(3) of the code and the regulations thereunder. The provisions of
this subsection 8.9 shall be deemed to be satisfied for any plan year if the
requirements of section 401(k)(12) of the code are satisfied.

8.10.      Correction of Section 401(k) Excess. In the event that the highly
           compensated group deferral percentage does not initially satisfy one
           of the tests referred to in subsection 8.9, the committee shall
           direct the trustee to distribute the excess contributions (as
           described below), together with the income allocable thereto
           (determined in accordance with Treas. Reg. Section
           1.401(k)-1(f)(4)(ii) using the safe harbor method described therein
           for determining the allocable income for the period between the end
           of the plan year and the date of distribution), to the appropriate
           highly compensated participants in accordance with the following
           provisions of this subsection 8.10.

(a)        The excess contributions shall be determined on an aggregate basis
           such that, after reduction of contributions to highly compensated
           employees in accordance with this subsection 8.10, the highly
           compensated group deferral percentage for the plan year satisfies one
           of the tests referred to in subsection 8.9.

(b)        The excess contributions to be distributed with respect to
           any highly compensated employee for any plan year shall
           be determined using a leveling method under which the
           amount of the elective deferrals of each highly
           compensated participant is reduced, in a series in the
           order of the amount of their respective elective
           deferrals beginning with the highest, to the extent
           necessary to cause the amount of the highly compensated
           participant's elective deferrals to equal the amount of
           the elective deferrals of the highly compensated
           participant with the next highest amount of elective
           deferrals or, if less, to cause the highly compensated
           group deferral percentage to satisfy one of the tests
           referred to in subsection 8.9.

                                        18
<PAGE>

(c)        The amount of excess contributions to be distributed with respect to
           any participant pursuant to this subsection 8.10 for any plan year
           shall be reduced by the amount of any employee tax-deferred
           contributions previously distributed to the participant for such plan
           year pursuant to subsection 8.8.

The committee shall make any distributions required by this subsection 8.10
after the close of the plan year for which the excess contributions were made
and no later than the close of the plan year following the plan year for which
the excess contributions were made. The provisions of this subsection 8.10 shall
not apply to any plan year for which the requirements of section 401(k)(12) of
the code are satisfied.

8.11.      Code Section 401(m)(2) Testing. For any plan year, the difference
           between (i) the average of the contribution percentages (as defined
           below) of each eligible employee who is highly compensated for the
           plan year (referred to hereinafter as the "highly compensated group
           contribution percentage"), and (ii) the average of the contribution
           percentages for the immediately preceding plan year of each eligible
           employee who was not highly compensated for such preceding plan year
           (referred to hereinafter as the "non-highly compensated group
           contribution percentage") shall satisfy one of the tests set forth in
           section 401(m)(2)(A) of the code. The "contribution percentage" for
           any eligible employee for a plan year shall be determined by dividing
           the sum of his employee after-tax contributions and the employer
           matched contributions made for him for the year by his section 415
           compensation for the year, subject to the following special rules:

(a)        the contribution percentage of each eligible employee with respect to
           whom no employee after-tax contributions and employer matched
           contributions are made for the year shall be counted as zero;

(b)        the contribution percentage for any eligible employee who is
           highly compensated and who is eligible to participate
           in one or more other qualified plans maintained by an
           employer or affiliate under which employee after-tax
           contributions or matching contributions may be made by
           or for him shall be determined as if all such
           contributions were made by or for him under the plan;
           and

(c)        in the event that this plan satisfies the requirements of
           sections 401(m), 401(a)(4), or 410(b) of the code only
           if aggregated with one or more other plans having the
           same plan year, or if one or more other plans having
           the same plan year as this plan satisfy the
           requirements of such sections of the code only if
           aggregated with this plan, then this subsection 8.11
           shall be applied as if all such plans were a single
           plan.

Application of the provisions of this subsection 8.11 shall be consistent with
the provisions of section 401(m) of the code and the regulations thereunder. The
provisions of this subsection 8.11 shall be deemed to be satisfied with respect
to employer matched contributions (and such contributions shall not be taken
into account for purposes of applying the foregoing provisions of this
subsection 8.11) for any plan year if the requirements of section 401(m)(11) of
the code are satisfied.

                                        19
<PAGE>

8.12.      Correction of Section 401(m) Excess. In the event that the highly
           compensated group contribution percentage for any plan year does not
           initially satisfy one of the tests referred to in subsection 8.11,
           the committee shall distribute the excess aggregate contributions (as
           described below), together with the income allocable thereto
           (determined in accordance with Treas. Reg. Section
           1.401(m)-1(e)(3)(ii) using the safe harbor method described therein
           for determining the allocable income for the period between the close
           of the plan year and the date of distribution), to the appropriate
           highly compensated participants in accordance with the following
           provisions of this subsection 8.12.

(a)        The excess aggregate contributions shall be determined on an
           aggregate basis for the plan such that, after reduction of excess
           aggregate contributions to highly compensated employees in accordance
           with this subsection 8.12, the highly compensated group contribution
           percentage for the plan year satisfies one of the tests referred to
           in subsection 8.11.

(b)        The excess aggregate contributions to be distributed with
           respect to any highly compensated employee for any plan
           year shall be determined using a leveling method under
           which the amount of the employee after-tax
           contributions and employer matched contributions for
           each highly compensated participant are reduced, in a
           series in the order of the amount of the sum of their
           respective employee after-tax contributions and
           employer matched contributions, beginning with the
           participant with the highest contributions, to the
           extent necessary to cause the amount of the highly
           compensated participant's employee after-tax
           contributions and employer matched contributions to
           equal the sum of the employee after-tax contributions
           and employer matched contributions of the highly
           compensated participant with the next highest amount of
           employee after-tax contributions and employer matched
           contributions, or, if less, to cause the highly
           compensated group contribution percentage to satisfy
           one of the tests referred to in subsection 8.11.

(c)        Any distribution required by this subsection 8.12 shall be made first
           from employee after-tax contributions for which no employer matched
           contribution has been made and then, if necessary, from a
           proportionate share of employee after-tax contributions and the
           employer matched contributions attributable thereto.

(d)        Notwithstanding the foregoing provisions of this subsection
           8.12, any excess aggregate contributions that are
           attributable to employer matched contributions (and the
           income allocable thereto) which are not vested in
           accordance with Section 9 on the last day of the plan
           year for which such contributions were made shall be
           forfeited and treated in the same manner as any other
           forfeiture under the plan.

The committee shall make any distribution (or forfeiture) required by this
subsection 8.12 after the close of the plan year for which the excess aggregate
contributions were made and no later than the close of the plan year following
the plan year for which such excess aggregate contributions were made. The
provisions of this subsection 8.12 shall be deemed to be satisfied with respect
to employer matched contributions (and such contributions shall not be taken
into

                                        20
<PAGE>

account for purposes of applying the foregoing provisions of this
subsection 8.12) for any plan year if the requirements of section 401(m)(11) of
the code are satisfied.

8.13.      Multiple Use of Alternative Limitation. Notwithstanding any other
           provision of this Section 8, if the 1.25 factor in sections
           401(k)(3)(A)(ii) and 401(m)(2)(A) of the code are both exceeded for a
           plan year, the sum of the highly compensated group deferral
           percentage and the highly compensated group contribution percentage
           may not exceed the aggregate limit (as defined in Treas. Reg. Section
           1.401(m)-2(b)(3). If the aggregate limit is exceeded, the leveling
           method of correction prescribed in subsection 8.12 shall be continued
           until the limitation set forth in this subsection 8.13 is satisfied.

8.14.      Highly Compensated Employee. An employee shall be "highly
           compensated" for any plan year if:

(a)        he was, at any time during the plan year or the preceding plan year,
           a 5-percent owner (as defined in Supplement A) of an employer or an
           affiliate; or

(b)        during the preceding plan year, he received section 415 compensation
           in excess of $80,000 (indexed for cost-of-living adjustments under
           section 415(d) of the code as provided in section 414(q) of the
           code).

A former employee of the company or any affiliate who was a highly compensated
employee when he separated from service with all affiliates or at any time after
attaining age 55 shall be treated as a highly compensated employee to the extent
required under section 414(q) of the code.

8.15.      Separate Testing of ESOP and Non-ESOP Portion of the Plan.
           Notwithstanding the foregoing provisions of this Section 8,
           contributions to the ESOP and contributions to the non-ESOP portion
           of the plan, respectively, for any plan year, shall be tested
           separately, including, but not limited to, for purposes of
           subsections 8.9 (relating to section 401(k)(3) testing), 8.11
           (relating to section 401(m)(2) testing) and subsection 8.13 (relating
           to multiple use of the alternative limitation), and, to the extent
           applicable, any excess contributions shall be corrected separately,
           subject to the following:

(a)        A participant contribution or an employer contribution to the plan
           for any plan year shall be considered to be a contribution to the
           ESOP for that year if, pursuant to subsection 6.2, it is initially
           invested in the Nicor Stock Fund, even if such contribution is
           subsequently transferred to another investment fund during or after
           that plan year pursuant to subsection 6.3.

(b)        A participant contribution or an employer contribution to
           the plan for any plan year shall be considered to be a
           contribution to the non-ESOP portion of the plan for
           that year if, pursuant to subsection 6.2, it is
           initially invested in an investment fund other than the
           Nicor Stock Fund, even if it is subsequently
           transferred to the Nicor Stock Fund during or after
           that plan year pursuant to subsection 6.3.

(c)        For purposes of section 410(b) and 401(a)(4) of the code, the
           employer profit sharing contribution to the plan for any plan year
           shall be considered to be a

                                        21
<PAGE>

           contribution for the non-ESOP portion of the plan for that year,
           even if it is subsequently transferred to the ESOP pursuant to an
           election described in subsection 6.3.

(d)        Amounts which, subsequent to their initial contribution and
           investment, are transferred among the investment funds pursuant to an
           election described in subsection 6.3 shall not be treated as a
           contribution to the ESOP or the non-ESOP portion of the plan for
           purposes of this Section 8 or section 410(b) or 401(a)(4) of the
           code.

(e)        To the extent applicable, separate deferral percentages and
           separate contribution percentages shall be determined
           for each eligible employee with respect to each of the
           ESOP and the non-ESOP portion of the plan.  For this
           purpose, an employee who is eligible to contribute to
           the plan at any time during a plan year shall be
           considered to be an eligible employee with respect to
           both the ESOP and the non-ESOP portion of the plan for
           that plan year, regardless of whether the participant
           actually elects to make a contribution.

(f)        An employee who is eligible to receive an allocation of an employer
           profit sharing contribution for a plan year shall be considered to be
           an eligible employee with respect to both the ESOP and the non-ESOP
           portion of the plan for that plan year.

(g)        In the event that the highly compensated group deferral
           percentage, or, to the extent applicable, the highly
           compensated group contribution percentage or the
           alternative limitation, each determined separately with
           respect to the ESOP and the non-ESOP portion of the
           plan, exceed the limitations of subsection 8.9, 8.11,
           or 8.13, respectively, distributions required to
           correct any such excess with respect to the ESOP shall
           be made first from the applicable accounts of the
           participant that, at the time of the corrective
           distribution, are invested in the Nicor Stock Fund, and
           then, to the extent necessary to satisfy any required
           correction, shall be made, pro rata, from the
           applicable accounts of the participant other than those
           invested in the Nicor Stock Fund.  To the extent that
           any such excess contributions occur with respect to the
           non-ESOP portion of the plan, distributions required to
           correct such excess shall be made first from the
           applicable accounts (other than those invested in the
           Loan Fund or the Nicor Stock Fund) in which the
           participant's accounts are invested at the time of the
           corrective distribution, pro rata, and then, if
           necessary to satisfy any such required correction, from
           the applicable accounts of the participant that are
           invested in the Nicor Stock Fund.

(h)        In the event that a correction is required under subsections 8.6
           (relating to excess annual additions) or 8.8 (correction of excess
           deferrals), any such corrective distribution shall be made, pro rata,
           from the investment funds (other than the Loan Fund) in which the
           applicable account is invested at the time of such corrective
           distribution.

                                        22
<PAGE>

(i)        For purposes of determining whether the requirements of subsections
           401(k)(12) or 401(m)(11) of the code are satisfied for any plan year,
           employer matched contributions made with respect to the ESOP and the
           non-ESOP portion of the plan shall be aggregated and treated as
           provided under the same plan.

SECTION 9.

                                Termination Dates

      A participant's "termination date" will be the date on which his
employment with the employers and the affiliates is terminated because of the
first to occur of the following events:

(a)        Retirement. The participant terminates employment with the employers
           and the affiliates on or after the date on which he attains age 55
           and completes at least 10 years of service.

(b)        Death. The participant's death.

(c)        Vested Resignation or Dismissal. The participant resigns or is
           dismissed from the employ of the employers and the affiliates before
           retirement in accordance with paragraph (a) next above but after
           completing at least 5 years of service.

(d)        Non-Vested Resignation or Dismissal. The participant resigns or is
           dismissed from the employ of the employers and the affiliates before
           retirement in accordance with paragraph (a) next above and prior to
           completing at least 5 years of service.

Notwithstanding the foregoing provisions of this Section 9, a participant shall
at all times have a nonforfeitable interest in his employee contribution
subaccounts, regardless of the number of his years of service.

SECTION 10.

                                  Distributions

10.1.           Fully Vested Benefits. Subject to the provisions of subsection
                10.8, if a participant's termination date occurs under paragraph
                9(a), 9(b) or 9(c), the balances in his accounts as at his
                distribution date, determined after all adjustments then
                required under the plan have been made (including adjustments
                for any outstanding loan balances), will be distributed, in one
                of the methods described in subsection 10.4, to or for the
                benefit of the participant, or in the event of his death, to or
                for the benefit of his beneficiary determined in accordance with
                the provisions of subsection 10.11. For purposes of this
                subsection and the following provisions of the plan, the term
                "distribution date" means the date as of which distribution of a
                participant's benefits commences in accordance with the
                provisions of subsection 10.7.

10.2.           Benefits on Non-Vested Resignation or Dismissal. Subject to the
                following provisions of this Section 10, if a participant's
                termination date occurs under paragraph 9(d), his account
                balances shall be treated as follows:

                                       23
<PAGE>

(a)        The balances in his employee contribution subaccounts as at
           his distribution date (after all adjustments then
           required under the plan have been made, including
           adjustments for any loan balances), will be
           distributed, in the method described in subsection
           10.4, to him or for his benefit, or, in the event of
           his death after termination of employment, to or for
           the benefit of his beneficiary, as soon as practicable
           after his distribution date.

(b)        The balance in his employer contribution subaccounts shall be
           forfeited in accordance with the following:

          (i)   if the participant receives a distribution (or deemed
                distribution as described below) of his vested
                account balances coincident with or after his
                termination date and prior to the date on which he
                incurs five consecutive one year breaks in
                service, then, as of the accounting date
                coincident with or next following the date on
                which the vested portion of his accounts are
                distributed to him, his entire balance in his
                employer contribution subaccounts (as adjusted
                through such accounting date in accordance with
                the provisions of subsection 7.1) will be
                forfeited; and

        (ii)    if the participant has not received a distribution (or deemed
                distribution as described below) of his vested account balances
                as of the date on which he incurs five consecutive one year
                breaks in service, the balance in his employer contribution
                subaccounts (as adjusted in accordance with the terms of the
                plan through the date on which he incurs five consecutive one
                year breaks in service) will be forfeited as of the date the on
                which he incurs such five consecutive one year breaks in
                service.

      For purposes of this paragraph (b), if the value of the vested portion of
      the participant's accounts is zero, the participant shall be deemed to
      have received a distribution of the vested portion.

10.3.           Restoration of Forfeitures. If a participant who terminated on a
                termination date described in paragraph 9(d) and with respect to
                whom a forfeiture occurred pursuant to paragraph 10.2(b) due to
                the distribution of the vested portion of the participant's
                accounts, including any deemed distribution, and the participant
                returns to the employ of an employer or affiliate prior to
                incurring five consecutive one year breaks in service, the
                amount that was forfeited in accordance with paragraph 10.2(b)
                (determined without adjustment for earnings and losses after the
                forfeiture occurred but including earnings and losses allocated
                to his accounts prior to the date of the forfeiture and that
                were included in the amount forfeited under paragraph 10.2(b))
                will be contributed by the employers to the extent that those
                employers were previously credited with the forfeitures
                (regardless of whether such contributions would be deductible by
                the employer, or would be out of current or accumulated
                profits), will be credited to the participant's employer
                contribution subaccount as of the last day of the plan year in
                which he was reemployed, and will not be considered an annual
                addition. The contributions required of an employer for any year
                under the provisions of the preceding sentence shall be reduced
                by the amount of any forfeitures which, under subsection 10.13,
                are considered to be employer contributions required under this
                subsection 10.3. An employer's contribution to be made for

                                                24
<PAGE>

                any plan year under this subsection 10.3 will be due on the last
                day of that year and, if not paid by the end of that year, shall
                be payable to the trustee not later than the time prescribed by
                law for filing that employer's federal income tax return for
                that plan year (including any extensions thereof), without
                interest.

10.4.           Manner of Payment. Subject to the provisions of this Section 10,
                a participant's accounts shall be distributed to or for the
                benefit of the participant, or in the event of his death, to or
                for the benefit of his beneficiary, by payment in a lump sum;
                provided, however that a participant whose termination date
                occurs under paragraph 9(a) and the beneficiary of a participant
                whose termination date occurs under paragraph 9(a) or 9(b) may
                elect distribution of the participant's account by one of the
                following methods:

(a)             By payment in a lump sum. OR

(b)             By payment in a series of substantially equal annual,
                semi-annual, quarterly or monthly installments over a period not
                exceeding the payee's life expectancy. OR

(c)             By purchase from the insurer and distribution to the payee of an
                annuity, subject to the following:

   (i)          Methods of payment shall be limited to (1) a single life annuity
                (as defined in subsection 10.5); (2) a joint and survivor
                annuity (as defined in subsection 10.5); (3) a single life
                annuity with a refund feature; and (4) a single life annuity
                with a fifteen year period certain feature.

  (ii)          An annuity benefit may be of the fixed or variable type under
                which annuity payments will commence as of the participant's
                distribution date. The premium paid to the insurer for an
                annuity will be charged to the participant's accounts when paid.
                The committee shall cause the annuity to be delivered to the
                person or persons entitled to payments under it in a
                nontransferable and noncommutable form.

 (iii)          Payments under the annuity shall satisfy the requirements of
                section 401(a)(9) of the code and the regulations thereunder,
                including the incidental death benefit requirement.

If a participant dies after distribution of his accounts have commenced in the
form described in paragraph (b) next above, the remaining portion of the
participant's account balances shall be distributed to or for the benefit of his
beneficiary in accordance with the distribution method in effect on the date of
the participant's death; provided, however, that the beneficiary may elect to
accelerate payment of such benefits.

10.5.      Payment in and Waiver of Joint and Survivor Annuity Form and Single
           Life Annuity Form. If a participant elects to have his account
           balances paid in accordance with paragraph 10.4(c), his account
           balances shall be applied to purchase a contract from an insurance
           company providing for payment in the form of a joint and survivor
           annuity (as defined below) if the participant is legally married
           under the laws of any jurisdiction on his distribution date, and

                                        25
<PAGE>

           in the form of a single life annuity (as described below) if the
           participant is unmarried on his distribution date, subject to the
           following provisions of this subsection 10.5. During an "election
           period" commencing no less than 30 days after the participant
           receives the election information described in subsection 10.7 and no
           more than 90 days before the participant's distribution date, a
           participant may waive payment in the joint and survivor annuity form
           (or single life annuity form in the case of an unmarried participant)
           and elect payment in one of the other forms permitted by subsection
           10.4. If a participant is legally married on his distribution date,
           then the waiver described in the preceding sentence will be effective
           only with spousal consent (as described in subsection 10.17). A
           participant may, at any time during his election period, revoke any
           prior waiver of the joint and survivor annuity form or single life
           annuity form, in which case his account balances shall be paid in the
           form of a joint and survivor annuity or a single life annuity, as
           applicable, in accordance with the foregoing provisions of this
           subsection 10.5. The term "joint and survivor annuity" means an
           annuity for the life of the participant with a survivor annuity for
           the life of his surviving spouse which is equal to 50 percent of the
           amount of the annuity payable during the joint lives of the
           participant and his spouse and which is the actuarial equivalent of a
           single life annuity for the life of the participant. The term "single
           life annuity" means an annuity payable for the payee's lifetime only.

10.6.      Payment in Form of Pre-Retirement Surviving Spouse Annuity. If a
           participant dies after electing to have his account balances
           distributed in accordance with paragraph 10.4(c) but prior to his
           distribution date, and if such participant is legally married under
           the laws of any jurisdiction on the date of his death, the entire
           balance in his accounts shall be applied to purchase a contract from
           an insurance company providing for payment in the form of a
           pre-retirement surviving spouse annuity (as described below), which
           contract shall be distributed to the participant's surviving spouse.
           The term "pre-retirement surviving spouse annuity" means an annuity
           payable to the surviving spouse for life. Distribution of the
           contract providing for the pre-retirement surviving spouse annuity
           shall be made, and payment under such contract shall commence, as of
           the accounting date which is coincident with, or next following the
           later of the participant's termination date or the 65th anniversary
           date of the participant's birth; provided, however, that the
           surviving spouse may elect to receive the pre-retirement surviving
           spouse annuity contract, and to commence receipt of payments under
           such contract, within a reasonable time following the participant's
           death. A participant's surviving spouse who is eligible for a
           pre-retirement surviving spouse annuity in accordance with the
           foregoing provisions of this subsection 10.6 may waive payment in
           that form and elect payment in any form permitted by subsection 10.4
           by filing an election with the committee after the participant's
           death.

10.7.      Election Information. As soon as practicable after a participant
           elects to have his account balances paid to him in accordance with
           paragraph 10.4(c) (but in no event less than 30 days nor more than 90
           days before the participant's distribution date), the committee will
           provide the participant with election information consisting of:

(a)        a written description of the joint and survivor annuity or single
           life annuity, as the case may be, and the relative financial effect
           of payment of his account balances in the respective form;

(b)        a notification of the right to waive payment in that form and the
           spouse's right, if applicable, with respect to that waiver;

                                        26
<PAGE>

(c)        a notification of the participant's right to rescind a prior
           revocation of distribution in the form of a joint and survivor
           annuity and the effect thereof; and

(d)        a general description of the eligibility conditions and other
           material features of the optional forms of distribution under the
           plan and information explaining the relative values of such optional
           forms of distribution.

The committee may make such election information available to a participant by:

(1)        personal delivery to him;

(2)        first-class mail, postage prepaid, addressed to the participant at
           his last known address as shown on the employer's records; or

(3)        permanent posting on a bulletin board located at the participant's
           work site.

A participant may request, by notice filed with the committee during his
election period, an explanation, written in nontechnical language, of the terms,
conditions and financial effect (in terms of dollars per monthly benefit
payment) of payment in the joint and survivor annuity form or single life
annuity form. If not previously provided to the participant, the committee shall
provide him with such explanation within 30 days of his request by one of the
methods described in paragraphs (1) or (2) next above, and the participant's
election period will be extended, if necessary, to include the 90th day next
following the date on which he receives such explanation.

10.8.      Commencement of Benefits. Benefits payable to or on account of any
           participant shall commence as of any date (but not retroactively)
           elected by the participant which is coincident with or next following
           the later of the date on which the participant attains age 65 years
           or his termination date, subject to the following:

(a)        Except as otherwise provided by the following provisions of this
           subsection 10.8, distribution of a participant's account balances
           shall commence no later than the sixtieth day after the last day of
           the plan year during which the participant attains age 65 years or,
           if later, during which his termination date occurs.

(b)        Subject to the following provisions of this subsection 10.8,
           a participant may elect to have distribution of his
           account balances commence in the form of a lump sum or
           an annuity as of any date that is coincident with or
           following his termination date and prior to his age
           70-1/2; provided, however, that a person who was a
           participant in the plan on April 1, 1998 and whose
           termination date occurs under paragraph 9(a) may elect
           to have his account balances commence in any form of
           payment permitted under the terms of the plan; and
           provided further that, if a participant does not make
           an election in accordance with this paragraph (b)
           within 90 days of his termination date, he shall be
           deemed to have elected to defer distribution of his
           account balances until the earlier of (i) the date that
           he subsequently elects to commence distribution, or
           (ii) the date on which he attains age 70-1/2.

                                        27
<PAGE>

(c)        If a participant dies before distribution of his account balances has
           commenced (as determined in accordance with the provisions of Treas.
           Reg. Section 1.401(a)(9)-1, B-5), the participant's account balances
           will be distributed as soon as practicable following the
           participant's death, subject to the following:

         (i)    if the participant has no designated beneficiary (within the
                meaning of Treas. Reg. Section 1.401(a)(9)-1,
                provided that, for purposes of this paragraph (c),
                a trust shall not be considered a designated
                beneficiary), and if the participant's beneficiary
                determined in accordance with paragraph 10.11(d)
                is not his surviving spouse, the participant's
                entire account balances will be distributed no
                later than the December 31 of the calendar year in
                which occurs the fifth anniversary of the
                participant's death;

       (ii)     except as otherwise specifically provided in subparagraph (iii)
                next below, distribution shall commence on or before December 31
                of the year immediately following the calendar year of the
                participant's death; and

       (iii)    if the deceased participant's beneficiary is the participant's
                surviving spouse, the surviving spouse may elect to defer
                distribution of the participant's account balances but not
                beyond the later of the December 31 of the year immediately
                following the calendar year in which the participant's death
                occurs or the December 31 of the year in which the participant
                would have attained age 70-1/2 and, if the surviving spouse dies
                before distribution commences, the participant's account
                balances will be distributed in accordance with the provisions
                of this paragraph (c) (other than the provisions of this
                subparagraph (c)(iii)) as though the surviving spouse were a
                participant; provided, however, that this subparagraph (c)(iii)
                shall not apply with respect to the surviving spouse of a
                participant whose termination date occurs under paragraph 9(c)
                or 9(d).

(d)        If the participant's death occurs after distribution of his
           benefits has commenced (as determined in accordance
           with the provisions of Treas. Reg. Section
           1.401(a)(9)-1, B-5), the remaining portion of his
           benefits shall be distributed to or for the benefit of
           his beneficiary in accordance with the distribution
           method in effect on the date of the participant's
           death; provided, however, that the beneficiary may
           elect to accelerate payment of such benefits.

(e)        Notwithstanding any other provision of this Section 10, if
           the value of a participant's nonforfeitable account
           balances, determined as of the accounting date that is
           coincident with or next following his termination date,
           does not exceed $5,000, the committee shall distribute
           such account balances to the participant or the
           participant's beneficiary, as the case may be, by
           payment in a lump sum as of such accounting date.

(f)        Notwithstanding any other provision herein to the contrary,
           distribution of a participant's account balances shall
           commence no later than April 1 of the

                                        28
<PAGE>

           calendar year following the calendar year in which the participant
           attains age 70-1/2 without regard to whether the
           participant's termination date has then occurred;
           provided, however, that if a participant, other than a
           5% owner, attained age 70-1/2 prior to January 1, 1988,
           distribution may be deferred until no later than
           April 1 of the calendar year following the calendar
           year in which his termination date occurs.

(g)        With respect to distributions under the plan made on or
           after January 1, 2002 for calendar years beginning on
           or after January 1, 2002, the plan will apply the
           minimum distribution requirements of section 401(a)(9)
           of the code in accordance with the regulations under
           section 401(a)(9) that were proposed on January 17,
           2001 notwithstanding any provision of the plan to the
           contrary.  The provisions of this paragraph (g) shall
           continue in effect until the last calendar year
           beginning before the effective date of the final
           regulations under section 401(a)(9) or such other date
           as may be published by the Internal Revenue Service.

10.9.      Compliance With Section 401(a)(9) of the Code. The provisions of
           subsections 10.4 and 10.8 are intended to reflect the requirements of
           section 401(a)(9) of the code, including the incidental death benefit
           requirements, and such subsections shall be interpreted and
           administered in accordance with the requirements of section 401(a)(9)
           of the code and the regulations thereunder, which requirements shall
           supersede any other provision of the plan which would otherwise be
           inconsistent with section 401(a)(9) of the code.

10.10  Assets to be Distributed. Except as otherwise provided in this
Section 10, amounts distributed to or on account of any participant from any
account maintained in the participant's name shall be made in cash. Prior to his
termination date or, if later, his distribution date, the participant or, in the
event of his death, his beneficiary, may elect to receive, in lieu of cash,
distribution from any account maintained in the participant's name under the
Nicor Stock Fund in the form of whole shares of Nicor stock, plus cash equal to
the fair market value of any fractional share of Nicor stock. If the trustee is
required to liquidate any account maintained in a participant's name under the
Nicor Stock Fund for any reason:

(a)        liquidation shall be made at the Nicor stock's fair market value
           determined as of the participant's distribution date; and

(b)        the amount of the cash proceeds of the liquidation shall be reduced
           by any commissions, brokerage fees and similar expenses incurred by
           the trustee as a result of the liquidation.

10.11  Designation of Beneficiary. A participant's beneficiary or
beneficiaries under the plan shall be determined in accordance with the
following provisions of this subsection 10.11:

(a)             Subject to the foregoing provisions of this Section 10, each
                participant from time to time may designate any legal or natural
                person or persons (who may be designated contingently or
                successively) to whom his benefits are to be paid if he dies
                before he receives all of his benefits.

                                        29
<PAGE>

(b)             Notwithstanding the foregoing provisions of this subsection
                10.11, if a participant is legally married under the laws of any
                jurisdiction on the date of his death, any designation of a
                beneficiary other than his spouse shall be effective only if
                spousal consent was obtained in accordance with subsection
                10.17.

(c)             A beneficiary designation form will be effective only when the
                signed form is filed with the committee while the participant is
                alive and will cancel all beneficiary designation forms signed
                earlier.

(d)             Except as otherwise specifically provided in this Section 10, if
                a deceased participant failed to designate a beneficiary as
                provided above, or if the beneficiary designated by a deceased
                participant dies before him, his benefits shall be paid to:

         (i)    the participant's surviving spouse; or

        (ii)    if the participant has no surviving spouse, the committee shall
                direct the trustee to pay the participant's benefits to the
                legal representative or representatives of the estate of the
                last to die of the participant or the participant's beneficiary.

           Notwithstanding the foregoing provisions of this paragraph (d), if
           the beneficiary of a participant survives the participant but dies
           prior to complete payment of the participant's benefits, the
           remainder of the benefits will be paid to the beneficiary designated
           by the beneficiary in accordance with the procedures set forth in
           this subsection 10.11 or, if no such beneficiary is named, to the
           estate of the beneficiary. Benefits payable to the beneficiary of a
           beneficiary shall be paid in a lump sum.

(e)        Notwithstanding the foregoing provisions of this subsection 10.11, in
           any case in which the provisions of subsection 10.6 apply with
           respect to a deceased participant's account balances, any beneficiary
           designation form filed with the committee with respect to such
           participant shall be without effect.

(f)        The term "beneficiary" as used in the plan means the person or
           persons to whom a deceased participant's benefits are payable under
           this subsection 10.11.

10.12  Interests Not Transferable. The interests of participants and their
beneficiaries under the plan and trust agreement are not subject to the claims
of their creditors and may not be voluntarily or involuntarily assigned,
alienated or encumbered, except (i) in the case of certain qualified domestic
relations orders which relate to the provision of child support, alimony
payments or marital property rights of a spouse, child or other dependent of a
participant and which meet such other requirements as may be imposed by section
414(p) of the code or regulations issued thereunder, (ii) pursuant to a
judgement or settlement order issued after August 5, 1997 (against a participant
convicted for a crime involving the misuse of plan funds or a civil judgement
for breach of fiduciary duty) meeting the requirements of section 401(a)(13)(C)
of the code, (iii) in the case of a tax lien obtained by the Internal Revenue
Service, or (iv) in the case of a voluntary revocable assignment to an employer
provided that such

                                        30
<PAGE>

assignments do not in the aggregate exceed 10 percent of any
benefit payment and further provided that such assignments are not made for the
purpose of defraying administrative costs of the plan. Notwithstanding any other
provision of the plan to the contrary, such domestic relations order may permit
distribution of the entire portion of the vested account balance of a
participant awarded to his alternate payee, in a lump sum payment as soon as
practicable after the committee determines that such order is qualified, without
regard to whether the participant would himself be entitled under the terms of
the plan to withdraw or receive a distribution of such vested amount at that
time.

10.13  Application of Forfeitures. The balance in any employer contribution
subaccount that is forfeited by a participant in accordance with subsection 10.2
shall be adjusted in accordance with the provisions of subsection 7.1 as of the
date that the forfeiture occurs. Forfeited amounts attributable to the prior
contributions of any employer shall be considered to be contributions to the
plan by that employer, and shall be applied to reduce the amount of the
contributions otherwise required of that employer under Section 4 and subsection
10.3 until exhausted or to pay reasonable plan expenses as directed by the
committee. The portion of any forfeited amount arising under the plan during any
period which is attributable to the prior contributions of any employer shall be
that proportion of such amount which the contributions made by that employer and
credited to the employer contribution subaccounts of the participant with
respect to whom the forfeiture occurs bear to the total contributions of all
employers which were credited to such account. Notwithstanding any other
provision of the plan, in no event shall any forfeiture arising under the plan
revert to any employer for any reason.

10.14  Distributions to Persons Under Disability. Notwithstanding the
foregoing provisions of this Section 10, in the event a participant or
beneficiary is declared incompetent and the committee receives evidence
satisfactory to it that a conservator or other person legally charged with the
care of his person or of his estate has been appointed, the amount of any
benefit to which such participant or beneficiary is then entitled from the trust
fund shall be paid to such conservator or other person legally charged with the
care of his person or estate.

10.15  Absence of Guaranty. None of the trustee, the committee or the employers
in any way guarantee the trust fund from loss or depreciation. The employers do
not guarantee any payment to any person. The liability of the trustee to make
any payment is limited to the available assets of the trust fund.

10.16  Missing Participants or Beneficiaries. Each participant and each
designated beneficiary must file with the committee from time to time in writing
his post office address and each change of post office address. Any
communication, statement or notice addressed to a participant or designated
beneficiary at his last post office address filed with the committee, or if no
address is filed with the committee then, in the case of a participant, at his
last post office address as shown on the employers' records, will be binding on
the participant and his designated beneficiary for all purposes of the plan.
None of the employers, the committee or the trustee will be required to search
for or locate a participant or designated beneficiary.

10.17  Spousal Consent. Any election by a participant under the plan which,
by its terms, requires spousal consent, shall be effective only if (i) the
participant's spouse consents in writing to such election; (ii) the consent
acknowledges the effect of the election and is witnessed

                                        31
<PAGE>

by a notary public (or, if permitted by the committee, a plan representative
appointed or approved by the committee); (iii) in the case of a
spousal consent to a beneficiary designation election, such election
designates a specific beneficiary which may not be changed without
spousal consent; and (iv) in the case of a participant's waiver of
a joint and survivor annuity, if the participant's distribution date
is prior to his 65th birthday, the spouse consents to the time of payment and
the spouse consents to the optional form of payment elected by the participant;
provided, however, that unless otherwise provided by a qualified domestic
relations order within the meaning of section 414(p) of the code, no such
consent shall be required if:

(a)        the participant and his spouse are legally separated or the
           participant has been abandoned (within the meaning of local law) and
           the participant has a court order to such effect; or

(b)        it is established to the satisfaction of a plan representative
           appointed or approved by the committee that the consent of the
           participant's spouse cannot be obtained because there is no spouse,
           because the spouse cannot be located or because of such other
           circumstances as the Secretary of the Treasury may prescribe in
           regulations.

10.18  Distribution and Withdrawal Elections. Distributions and withdrawals
(other than distributions and withdrawals to which the consent requirements of
section 411(a)(11) or 417 of the code do not apply) shall be subject to the
following:

(a)        not less than 30 days nor more than 90 days before the date as of
           which such distribution is made, the participant shall be informed of
           his right to defer distribution in accordance with the provisions of
           the applicable subsection and, if applicable, shall be provided with
           a written explanation of the optional forms of benefit available to
           him under the plan;

(b)        no election to commence distribution prior to the participant's 65th
           birthday shall be effective unless it is made in writing, after the
           participant has received the notice described in paragraph (a) next
           above, and not more than 90 days before the date as of which the
           distribution is made; and

(c)        spousal consent shall be obtained to the extent required by the
           provisions of subsection 10.5.

Notwithstanding the foregoing, distributions or withdrawals may commence less
than 30 days after the participant is informed of his right to defer
distribution or withdrawal in accordance with the applicable section or
subsection if:

(1)        the participant is clearly informed that he has a right to a period
           of at least 30 days after being so informed to consider the decision
           of whether or not to elect a distribution or withdrawal (and, if
           applicable, a particular form of distribution); and

(2)        the participant, after being informed of his rights in accordance
           with subparagraph (1) next above, affirmatively elects a distribution
           or withdrawal.

                                        32
<PAGE>

10.19  Direct Rollover to an Eligible Retirement Plan. Notwithstanding any
provision of the plan to the contrary that would otherwise limit a distributee's
election under this subsection 10.19, a distributee may elect, at the time and
in the manner prescribed by the committee, to have any portion of an "eligible
rollover distribution" (as defined in section 402(c)(4) of the code) paid
directly to an eligible retirement plan specified by the distributee in a direct
rollover. For purposes of this subsection 10.19, the following definitions shall
apply:

(a)        An "eligible retirement plan" means an individual retirement
           account described in section 408(a) of the code, an
           individual retirement annuity described in section
           408(b) of the code, an annuity plan described in
           section 403(a) of the code or a qualified trust
           described in section 401(a) of the code, that accepts
           the distributee's eligible rollover distribution;
           provided, 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.

(b)        A "distributee" means an employee or former employee and 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
           section 414(p) of the code.

(c)        A "direct rollover to an eligible retirement plan" means a payment by
           the plan to the eligible retirement plan specified by the
           distributee.

10.20  Distribution Only Upon Separation From Service. Notwithstanding any
other provision of the plan to the contrary, a participant may not commence
distribution of his employee tax-deferred contribution account pursuant to this
Section 10, even though he has otherwise had a termination date under Section 9,
unless or until he also has a "separation from service" within the meaning of
section 401(k)(2)(B) of the code. The foregoing restriction shall not apply,
however, if the participant's termination date occurs in connection with the
sale by an employer to an unrelated corporation of at least 85 percent of the
assets of a trade or business, or the sale of its interest in a subsidiary to an
unrelated entity, provided (a) the participant remains employed in such trade or
business or by such subsidiary after the sale, (b) the employer continues to
maintain the plan after the sale, (c) no transfer of the participant's accounts
occurs or is scheduled to occur after the sale pursuant to subsection 14.3 to a
plan of such subsidiary or of the purchaser of such assets (or any entity
affiliated therewith), and (d) the participant receives distribution of his
account balances (less any outstanding loan balances) under the plan in a lump
sum by the end of the second calendar year after the year in which the sale
occurs.

10.21 Transfers to Thrift Plan. If an employee of an employer:

(a)        ceases to satisfy the requirements of paragraph 2.1(b);

(b)        continues to be employed by an employer or an affiliate; and

(c)        coincident with his failure to satisfy the requirements of paragraph
           2.1(b), he becomes eligible to participate in the thrift plan;

                                        33
<PAGE>

then his account balances under the plan, determined as of the date described in
paragraph (a) next above, shall be transferred to the corresponding accounts
under the thrift plan and, for periods thereafter, he shall cease to be a
participant in the plan and shall be a participant in the thrift plan, subject
to the terms and conditions of the thrift plan.

SECTION 11.

                              Withdrawals and Loans

11.1.      Pre-Termination Withdrawals From Employee After-tax Account. Subject
           to the provisions of subsections 11.5 and 11.6, as of any date but
           not more frequently than twice during any calendar year, a
           participant who is employed by an employer or an affiliate may
           withdraw from his employee after-tax account an amount that is not
           less than $200 and not greater than the amount credited to his
           employee after-tax account (less any outstanding loan balance);
           provided, however, that a participant who has attained age 59-1/2 as
           of the effective date of the withdrawal may withdraw an amount that
           does not exceed the vested balance of his employee after-tax account.

11.2.      Pre-Termination Withdrawals From Employee Tax-deferred Account.
           Subject to the provisions of subsections 11.5, 11.6 and 11.7, as of
           any date a participant who is employed by an employer or affiliate
           may, by showing of hardship (as described in subsection 11.3),
           withdraw from his employee tax-deferred account an amount that is not
           less than $1,000 and not more than the least of:

(a)        an amount equal to:

  (i)      the amount credited to the participant's employee tax-deferred
           contribution subaccount, reduced by

 (ii)      the sum of the amount previously withdrawn from the participant's
           employee tax-deferred subaccount after December 31, 1988 (including
           any outstanding loan balance), plus any earnings credited to the
           participant's employee tax-deferred subaccount for periods after
           December 31, 1988.

(b)        the amount credited to the participant's employee tax-deferred
           contribution subaccount; or

(c)        the amount necessary to satisfy such hardship in accordance with
           subsection 11.3.

Subject to the provisions of subsection 11.7, as of any date, a participant who
is employed by an employer or an affiliate and who has attained age 59-1/2 as of
the effective date of the withdrawal may withdraw an amount that does not exceed
the vested balance (less any outstanding loan balance) of his employee
tax-deferred contribution subaccount.

11.3.           Hardship. A withdrawal shall be made on account of "hardship" if
                the requirements of paragraphs (a) and (b) next below are met:

                                        34
<PAGE>

(a)        The withdrawal is requested because of the participant's
           immediate and heavy financial need on account of:

   (i)          uninsured, deductible medical expenses incurred by the
                participant, the participant's spouse or any dependent of the
                participant (as defined in section 152 of the code);

  (ii)          the purchase (excluding mortgage payments) of a principal
                residence of the participant;

 (iii)          payment of tuition for up to the next 12 months of
                post-secondary education for the participant, or his spouse or
                children (including step-children); or

  (iv)          the need to prevent (1) the eviction of the participant from his
                principal residence or (2) foreclosure on the mortgage of the
                participant's principal residence.

(b)        The withdrawal is necessary to satisfy the immediate and
           heavy financial need of the participant.  A withdrawal
           will be considered necessary under this paragraph (b)
           if the amount of the withdrawal does not exceed the
           amount required to relieve the financial need,
           including any federal, state or local income taxes or
           penalties reasonably anticipated to be incurred by the
           participant on account of the withdrawal, and if the
           participant signs a statement indicating that he has no
           other reasonable means of satisfying the immediate and
           heavy financial need.

11.4.           Loans. A participant who is an employee of an employer or an
                affiliate or who is otherwise required to be given the
                opportunity to borrow under applicable regulations may, by
                following such procedures as the committee may from time to time
                establish, request a loan to be made to him from his accounts,
                subject to the following:

(a)        No loan shall be made to a participant if, immediately after
           such loan, the sum of the outstanding balances (including
           principal and interest) of all loans made to him under this plan
           and under any other qualified retirement plans made by
           affiliates would exceed $50,000, reduced by the excess, if any,
           of:

           (i)  the highest outstanding balance of all loans to the participant
                from the plans during the one-year period ending on the day
                immediately before the date on which the loan is made; over

          (ii)  the outstanding balance of loans from the plans to the
                participant on the date on which such loan is made;

           and no loan shall be made to a participant if the aggregate amount of
           that loan and the outstanding balance of any other loans to the
           participant would exceed one-half of the total vested balance of the
           participant's account balances under the plan as of the date the loan
           is made.

                                        35
<PAGE>

(b)        Each loan to a participant shall be charged against the
           participant's accounts in the following order: (i)
           rollover subaccount, (ii) employee tax-deferred
           contribution subaccount (non-ESOP), (iii) employee
           tax-deferred contribution subaccount (ESOP), (iv)
           tax-deferred employer matched contribution subaccount
           (non-ESOP), (v) employee after-tax employer matched
           subaccount (non-ESOP), (vi) tax-deferred employer
           matched contribution subaccount (ESOP), (vii) employee
           after-tax employer matched contribution subaccount
           (ESOP), (viii) employee after-tax contribution
           subaccount (non-ESOP), and (ix) employee after-tax
           contribution subaccount (ESOP).  Each loan shall be
           charged against each investment fund in which his
           accounts are invested in the same ratio as the value of
           his interest in such fund with respect to the
           applicable account bears to the total of all his
           interest in that account.

(c)        Each loan shall be evidenced by a written note providing for:

   (i)     a reasonable repayment period, in whole months, of not less than six
           months nor more than 60 months from the date of the loan (including
           loans used to acquire a dwelling unit to be used as a principal
           residence);

  (ii)     a reasonable rate of interest;

 (iii)     substantially equal payments of principal and interest over the term
           of the loan;

  (iv)     such other terms and conditions as the committee shall determine.

(d)        Only two loans may be outstanding any time.

(e)        Loans to participants shall be invested in the Loan Fund.

(f)        Payments of principal and interest to the trustee with respect to any
           loan to a participant:

   (i)     shall reduce the outstanding balance with respect to that loan;

  (ii)     shall reduce the balance of the Loan Fund reflecting the loan;

 (iii)     shall be credited to the participant's accounts in the following
           order: (A) employee after-tax contribution subaccount (non-ESOP), (B)
           employee after-tax contribution subaccount (ESOP), (C) employee
           after-tax employer matched contribution subaccount (non-ESOP), (D)
           tax-deferred employer matched contribution subaccount (non-ESOP), (E)
           employee after-tax employer matched contribution subaccount (ESOP),
           (F) tax-deferred employer matched contribution subaccount (ESOP), (G)
           employee tax-deferred contribution subaccount (non-ESOP), (H)
           employee tax-deferred contribution subaccount (ESOP), and (I)
           rollover subaccount; and

                                        36
<PAGE>

  (iv)     shall be invested in the investment funds (other than the Loan Fund)
           in accordance with his current investment directions.

(g)        A participant's obligation to repay a loan (or loans) from the plan
           shall be secured by the participant's vested interest in the plan.

(h)        The committee may, from time to time, establish loan origination fees
           and loan administrative fees which may be charged to the
           participant's accounts under the plan, pro rata.

(i)        Loan repayments may only be made by payroll deductions; provided,
           however, that if a participant is on an approved leave of absence,
           loan repayments, may be made from certified checks. No partial loan
           repayments may be made but a loan may be repaid in full at any time.

(j)        Any loan to a participant shall become immediately due and
           payable upon the earlier of (i) 90 days after the end
           of the month following the month in which the
           participant's employment with the employers and
           affiliates terminates, unless such participant's
           accounts are scheduled to be transferred to another
           qualified plan, including transfers under subsection
           10.19 of the plan, (ii) the end of the sixth pay period
           after a payment is due and remains unpaid.
           Notwithstanding the foregoing, any loan to a
           participant made after December 31, 2002 shall become
           immediately due and payable as of the last day of the
           calendar quarter following the calendar quarter in
           which any required installment was due and remains
           unpaid.  Notwithstanding any other provision of the
           plan to the contrary, if the outstanding balance of
           principal and interest on any loan is not paid at the
           expiration of its term or upon acceleration in
           accordance with the foregoing provisions of this
           paragraph (j), a default shall occur and the trustee
           shall apply all or a portion of the participant's
           vested interest in the plan in satisfaction of such
           outstanding obligation, but only to the extent such
           vested interest (or portion thereof) is then
           distributable under applicable provisions of the code
           and under the terms of the plan.  If necessary to
           satisfy the entire outstanding obligation, such
           application of the participant's vested interest may be
           executed in a series of actions as amounts credited to
           the participant's account become distributable.

(k)        If distribution is to be made to a beneficiary in accordance with
           subsection 10.6, any outstanding loan shall be canceled and the
           unpaid balance of the loan, together with any accrued interest
           thereon, shall be treated as a distribution to or on behalf of the
           participant immediately prior to commencement of distribution to the
           beneficiary.

(l)        The committee shall establish uniform procedures for applying for a
           loan, evaluating loan applications, and setting reasonable rates of
           interest, which shall be communicated to participants in writing.

11.5.      Partial Withdrawals. Subject to the provisions of subsections 11.6
           and 11.7, as of any date a participant whose termination date has
           occurred under paragraph 9(a) or 9(b) and

                                        37
<PAGE>

           whose account balances have
           not been completely distributed pursuant to Section 10, and the
           beneficiary of any such participant who is deceased, may elect to
           withdraw an amount that is not less than $200 and not greater than
           the amount credited to the participant's accounts as of the next
           preceding accounting date, subject to the following:

(a)        neither a participant whose termination date occurs under paragraph
           9(c) or (d) nor the beneficiary of such a participant may elect a
           withdrawal under this subsection 11.5; and

(b)        not more than twelve withdrawals may be made with respect to any
           participant under this subsection 11.5 during any 12 month period and
           any withdrawal under subsections 11.1 or 11.2 shall be deemed to be a
           partial withdrawal under this subsection 11.5 for purposes of the
           limitation in this paragraph (b).

11.6.      Order of Pre-Termination Withdrawals From Accounts. A participant may
           not withdraw any amount from his employee tax-deferred account in
           accordance with the provisions of subsection 11.2 as of any date
           unless he has withdrawn all amounts which could then be withdrawn by
           him in accordance with subsection 11.1.

11.7.      Order of Post-Termination Withdrawals From Accounts. Withdrawals in
           accordance with the provisions of subsection 11.5 shall be made in
           the following order:

(a)        first, from the participant's employee after-tax contribution
           subaccount until exhausted;

(b)        next, from the participant's employee after-tax employer matched
           contribution subaccount until exhausted;

(c)        next, from the participant's employee tax-deferred contribution
           subaccount until exhausted;

(d)        next, from the participant's tax-deferred employer matched
           contribution subaccount until exhausted; and

(e)        finally, from the participant's profit sharing account until
           exhausted.

Notwithstanding the foregoing provisions of this subsection 11.7, withdrawals in
accordance with the provisions of subsection 11.5 by a participant or
beneficiary who is receiving benefits in the form described in subsection
10.4(b) shall be made, pro rata, from the participant's accounts.

11.8. Order of Withdrawal From Investment Funds. A withdrawal from a
participant's accounts in accordance with this Section 11 shall be made, in
cash, pro rata from the investment funds in which his accounts are invested. The
amount of any withdrawal from the Nicor Stock Fund shall be determined on the
basis of the fair market value of the shares of Nicor stock on his distribution
date.

11.9. No Make-up of Withdrawals. A participant may not make-up or repay any
amount withdrawn in accordance with the provisions of this Section 11.

                                        38
<PAGE>

SECTION 12.

                                   Nicor Stock

12.1. Purchase of Nicor Stock. The trustee may purchase shares of Nicor stock in
the open market, through a dividend reinvestment plan or by private purchase;
provided, however, that no private purchase of shares of Nicor stock shall be
made at a price that is greater per share than the last preceding sale price for
shares of Nicor stock as reported on the New York Stock Exchange Composite List.

12.2. Voting Nicor Stock. Voting rights with respect to shares of Nicor stock
held in the Nicor Stock Fund shall be exercised in accordance with the
provisions of Supplement B.

SECTION 13.

                                  The Committee

13.1.      Membership. The committee referred to in subsection 1.2 shall consist
           of one or more persons appointed by the Board of Directors of the
           company. The members of the committee shall be the "named
           fiduciaries" (as described in section 402 of ERISA) under the plan.
           Except as otherwise specifically provided in this Section 13, in
           controlling and managing the operation and administration of the
           plan, the committee shall act by the concurrence of a majority of its
           then members by meeting or by writing without a meeting. The
           committee, by unanimous written consent, may authorize any one of its
           members to execute any document, instrument or direction on its
           behalf. A written statement by a majority of the committee members or
           by an authorized committee member shall be conclusive in favor of any
           person (including the trustee) acting in reliance thereon.

13.2.      Rights, Powers and Duties. The committee shall have such authority as
           may be necessary to discharge its responsibilities under the plan,
           including the following powers, rights and duties:

(a)        To select a chairman who shall be a member of the committee.

(b)        To select a secretary who may, but need not, be a member of the
           committee.

(c)        To conclusively interpret and construe the provisions of the plan and
           to remedy ambiguities, inconsistencies and omissions of whatever kind
           or nature.

(d)        To adopt, and apply in a uniform and nondiscriminatory manner to all
           persons similarly situated, such rules of procedure and regulations
           as, in its opinion, may be necessary for the proper and efficient
           administration of the plan, and as are consistent with the provisions
           of the plan.

(e)        To conclusively determine all questions arising under the plan,
           including the power to determine rights or eligibility of employees
           or former employees, and the respective benefits of participants and
           others entitled thereto.

                                        39
<PAGE>

(f)        To maintain and keep adequate records concerning the plan and
           concerning its proceedings and acts in such form and detail as the
           committee may decide.

(g)        To direct all benefit payments under the plan.

(h)        To furnish the employers with such information with respect to the
           plan as may be required by them for tax or other purposes.

(i)        By unanimous action of the members then acting, to employ agents and
           counsel (who also may be employed by the employers or the trustee)
           and to delegate to them, in writing, such powers as the committee
           considers desirable.

(j)        To act as the "plan administrator" (as defined in section 414(g) of
           the code) for purposes of establishing and implementing procedures to
           determine the qualified status of domestic relations orders (in
           accordance with the requirements of section 414(p) of the code) and
           to administer distributions under such qualified orders.

13.3.      Information to be Furnished to Committee. Each employer shall furnish
           the committee such data and information as the committee may require.
           As a condition of receipt of benefits under the plan, the person
           making claim therefor must furnish to the committee such documents,
           evidence, data or other information as the committee considers
           desirable to determine eligibility for such benefits.

13.4.      Committee's Decision Final. To the extent permitted by law, any
           interpretation of the plan and any decision on any matter within the
           discretion of the committee made by the committee in good faith is
           binding on all persons. A misstatement or other mistake of fact shall
           be corrected when it becomes known, and the committee shall make such
           adjustment on account thereof as it considers equitable and
           practicable. Notwithstanding any other provision of the plan to the
           contrary, benefits under the plan will be paid only if the committee,
           in its discretion, determines that the applicant is entitled to them
           pursuant to the terms of the plan.

13.5.      Remuneration and Expenses. No remuneration shall be paid to any
           committee member as such. However, the expenses of the committee
           members (including fees of persons employed by them in accordance
           with paragraph 13.2(i)) incurred in the performance of a committee
           function or the administration of the trust fund shall be paid from
           the trust fund in accordance with the provisions of the trust
           agreement to the extent not paid by the employers.

13.6.      Indemnification of the Committee. The committee and the individual
           members thereof shall be indemnified by the company against any and
           all liabilities, losses, costs, and expenses (including legal fees
           and expenses) of whatsoever kind and nature which may be imposed on,
           incurred by or asserted against the committee or the members by
           reason of the performance of a committee function if the committee or
           such members did not act dishonestly or in willful violation of the
           law or regulation under which such liability, loss, cost or expense
           arises.

13.7.      Exercise of Committee's Duties. Notwithstanding any other provisions
           of the plan, the committee shall discharge its duties hereunder
           solely in the interests of the plan participants and other persons
           entitled to benefits under the plan, and:

                                        40
<PAGE>

(a)        for the exclusive purpose of providing benefits to plan participants
           and other persons entitled to benefits thereunder; and

(b)        with the care, skill, prudence and diligence under the circumstances
           then prevailing that a prudent man acting in a like capacity and
           familiar with such matters would use in the conduct of an enterprise
           of a like character and with like aims.

13.8.      Resignation or Removal of Committee Member. A committee member may
           resign at any time by thirty days advance written notice to the
           company, the trustee and the other committee members. The Board of
           Directors of the company may remove a committee member by giving
           advance written notice to him, the trustee and the other committee
           members.

13.9.      Appointment of Successor Committee Members. The Board of Directors of
           the company may fill any vacancy in the membership of the committee
           and shall give prompt written notice thereof to the other committee
           members, the other employers and the trustee. While there is a
           vacancy in the membership of the committee, the remaining committee
           members shall have the same powers as the full committee until the
           vacancy is filled.

13.10     Interested Committee Member. A member of the committee may not decide
          or determine any matter or question concerning his own benefits under
          the plan unless such decision could be made by him under the plan if
          he were not a member of the committee.

SECTION 14.

                            Amendment and Termination

14.1.      Amendment. While the employers expect and intend to continue the
           plan, the company must reserve and reserves the right, subject to the
           provisions of the trust, to amend the plan at any time, except that
           no amendment shall reduce a participant's benefits to less than the
           amount he would be entitled to receive if he had resigned from the
           employ of all of the employers and the affiliates on the date of the
           amendment.

14.2.      Termination. The plan, as applied to all employers, will terminate on
           the date it is terminated by the company, provided that written
           notice is provided to the trustee, the committee, and the other
           employers. The plan, as applied to any employer, will terminate on
           the first to occur of the following:

(a)        the date it is terminated by that employer if thirty days advance
           written notice of the termination is given to the trustee, the
           committee and the other employers;

(b)        the date that employer completely discontinues its contributions
           under the plan;

(c)        the date that employer is judicially declared bankrupt or insolvent;
           or

(d)        the dissolution, merger, consolidation or reorganization of
           that employer, or the sale by that employer of all or
           substantially all of its assets, except that, subject
           to the provisions of subsection 14.3, with the consent
           of the company, in any such

                                     41

           event arrangements may be
           made whereby the plan will be continued by any
           successor to that employer or any purchaser of all or
           substantially all of that employer's assets, in which
           case the successor or purchaser will be substituted for
           that employer under the plan.

14.3.      Merger and Consolidation of Plan, Transfer of Plan Assets. In the
           case of any merger or consolidation with, or transfer of assets and
           liabilities to, any other plan, provisions shall be made so that each
           affected participant in the plan on the date thereof (if the plan, as
           applied to his employer, then terminated) would receive a benefit
           immediately after the merger, consolidation or transfer which is
           equal to or greater than the benefit he would have been entitled to
           receive immediately prior to the merger, consolidation or transfer if
           the plan, as applied to his employer, had then terminated.

14.4.      Vesting and Distribution on Termination and Partial Termination. On
           termination of the plan in accordance with subsection 14.2 or on
           partial termination of the plan, as applied to any employer, by
           operation of law, the date of termination or partial termination, as
           the case may be, will be an accounting date and, after all
           adjustments then required have been made, each affected participant's
           benefits will be nonforfeitable. If, on termination of the plan as
           applied to any employer, a participant remains an employee of the
           employers, or an affiliate, the amount of his benefits shall be
           retained in the trust until after his termination of employment with
           all of the employers and affiliates and shall be paid to him in
           accordance with the provisions of Section 10. The benefits payable to
           a participant whose employment with all of the employers and
           affiliates is terminated coincident with the termination of the plan
           as applied to his then employer (and the benefits payable to an
           affected participant on partial termination of the plan) shall be
           paid to him in accordance with the provisions of Section 10. All
           appropriate accounting provisions of the plan will continue to apply
           until the benefits of all affected participants have been distributed
           to them.

14.5.      Notice of Amendment, Termination or Partial Termination. Affected
           persons will be notified of an amendment, termination or partial
           termination of the plan as required by law.

<PAGE>

                                  SUPPLEMENT A
                                       TO
                  NICOR COMPANIES SAVINGS INVESTMENT PLAN


Application     A-1. This Supplement A to Nicor Companies Savings Investment
                Plan (the "plan") shall be applicable on and after the date on
                which the plan becomes top-heavy (as described in subsection
                A-5).

Effective Date  A-2. The effective date of this Supplement A is January 1,
                2001.

Definitions     A-3. Unless the context clearly implies or indicates the
                contrary, a word, term or phrase used or defined in the plan is
                similarly used or defined for purposes of this Supplement A.

Affected        A-4. For purposes of this Supplement A, the term Participant
                "affected participant" means each participant who
                is employed by an employer or an affiliate during any plan year
                for which the plan is top-heavy; provided, however, that the
                term "affected participant" shall not include any participant
                who is covered by a collective bargaining agreement if
                retirement benefits were the subject of good faith bargaining
                between his employer and his collective bargaining
                representative.

Top-Heavy       A-5.  The plan shall be "top-heavy" for any plan
                year if, as of the determination date for that
                year (as described in paragraph (a) next below),
                the present value of the benefits attributable to
                key employees (as defined in subsection A-6) under
                all aggregation plans (as defined in subsection
                A-7) exceeds 60% of the present value of all
                benefits under such plans.  The foregoing
                determination shall be made in accordance with the
                provisions of section 416 of the code.  Subject to
                the preceding sentence:

               (a)   The determination date with respect
                     to any plan for purposes
                     of determining top-heavy status for any plan
                     year of that plan shall be the last day of
                     the preceding plan year or, in the case of
                     the first plan year of that plan, the last
                     day of that year.  The present value of
                     benefits as of any determination date shall
                     be determined as of the accounting date or
                     valuation date coincident with or next
                     preceding the determination date.  If the
                     plan years of all aggregation plans do not
                     coincide, the top-heavy status of the plan on
                     any determination date shall be determined by
                     aggregating the present value of plan
                     benefits on that date with the present value
                     of the benefits under each other aggregation
                     plan determined as of the determination date
                     of such other aggregation plan which occurs
                     in the same calendar year as the plan's
                     determination date.

               (b)   Benefits under any plan as of any determination date shall
                     include the amount of any distributions from
                     that plan made during the plan year which
                     includes the determination date or during any
                     of the preceding four plan years, but shall
                     not include any amounts attributable to
                     employee contributions which are deductible
                     under section 219 of the code, any amounts
                     attributable to employee-initiated rollovers
                     or transfers made after December 31, 1983
                     from a plan maintained by an unrelated
                     employer, or, in the case of a defined
                     contribution plan, any amounts attributable
                     to contributions made after the determination
                     date unless such contributions are required
                     by section 412 of the code or are made for
                     the plan's first plan year.

               (c)   Benefits attributable to a participant shall include
                     benefits paid or payable to a beneficiary of the
                     participant, but shall not include benefits paid or payable
                     to any participant who has not been employed by an employer
                     or affiliate during any of the five plan years ending on
                     the applicable determination date.

               (d)   The accrued benefit of any participant who is a non-key
                     employee with respect to a plan but who was a key employee
                     with respect to such plan for any prior plan year shall not
                     be taken into account.

               (e)   The accrued benefit of a non-key employee shall be
                     determined under the method which is used for
                     accrual purposes for all plans of the
                     employer and affiliates; or if there is not
                     such a method, as if the benefit accrued not
                     more rapidly than the slowest accrual rate
                     permitted under section 411(b)(1)(C) of the
                     code.

               (f)   The present value of benefits under all defined benefit
                     plans shall be determined on the basis of the actuarial
                     assumptions specified in the retirement plan.

Key Employee    A-6.  The term "key employee" means a participant
                or beneficiary under any plan who is a key
                employee within the meaning ascribed to that term
                by section 416(i) of the code.  Subject to the
                preceding sentence, for plan years beginning after
                December 31, 1988, the term key employee includes
                any employee or deceased employee (or the
                beneficiary of such deceased employee) who at any
                time during the plan year which includes the
                determination date or during any of the four
                preceding plan years was:

               (a)   an officer of any employer or affiliate with compensation
                     (as defined in subsection A-8) for that year
                     in excess of 50 percent of the amount in
                     effect under section 415(b)(1)(A) of the code
                     for the calendar year in which that year
                     ends; provided, however, that the maximum
                     number of employees who shall be considered
                     key employees under this paragraph (a) shall
                     be 50;

               (b)   one of the 10 employees owning the largest interests in any
                     employer or any affiliate (disregarding any
                     ownership interest which is less than1/2of
                     one percent), excluding any employee for any
                     plan year whose compensation for that year
                     did not exceed the applicable amount in
                     effect under section 415(c)(1)(A) of the code
                     for the calendar year in which that year ends;

               (c)   a 5% owner of any employer or of any affiliate; or

               (d)   a 1% owner of any employer or any affiliate having
                     compensation in excess of $150,000.

Non-Key          A-7.  The term "non-key employee" means any
Employee         employee or beneficiary of a deceased employee who
                 is not a key employee).

Compensation    A-8.  The term "compensation" for purposes of this
                Supplement A means compensation within the meaning
                of section 415(c)(3) for that year, not exceeding
                $160,000 (as adjusted in each case in accordance
                with 401(a)(17) of the code); provided, however,
                that solely for purposes of determining who is a
                key employee, the term "compensation" means
                compensation as defined in section 414(q)(7) of
                the code.

Aggregation
Plan           A-9. The term "aggregation plan" means the plan and each other
               retirement plan maintained by an employer or affiliate
               which is qualified under section 401(a) of the code and which:

             (a)     during the plan year which includes the applicable
                     determination date, or during any of the preceding four
                     plan years, includes a key employee as a participant;

             (b)     during the plan year which includes the applicable
                     determination date, or during any of the preceding four
                     plan years, enables the plan or any plan in which a key
                     employee participates to meet the requirements of section
                     401(a)(4) or 410 of the code; or

             (c)     would meet the requirements of sections 401(a)(4) and 410
                     if it were considered together with the plan and all other
                     plans described in paragraphs (a) and (b) next above.

Required
Aggregation     A-10. The term "required aggregation plan" means a plan
Plan           described in either paragraph (a) or (b) of subsection A-9.

Permissive
Aggregation     A-11.  The term "permissive aggregation plan" means
Plan            a plan described in paragraph (c) of subsection A-9.


Vesting         A-12.  For any plan year during which the plan is
                top-heavy, the account balances of any affected
                participant who has completed at least three years
                of service shall be 100% vested.  If the plan
                ceases to be top-heavy for any plan year, the
                provisions of this subsection A-12 shall continue
                to apply to (i) the portion of an affected
                participant's account balances which were accrued
                and vested prior to such plan year (adjusted for
                subsequent earnings and losses) and (ii) in the
                case of an affected participant who had completed
                at least 5 years of service, the portion of his
                account balances which accrues thereafter.

Minimum         A-13.  For any plan year during which the plan is
Contribution    top-heavy, the minimum amount of employer
                contributions and forfeitures (excluding for plan years
                beginning after December 31, 1988, elective contributions
                described in section 401(k) of the code and employer matching
                contributions described in section 401(m) of the code)
                allocated to the accounts of each affected participant who is
                employed by an employer or affiliate on the last day of that
                year, who is not a key employee and who is not entitled to a
                minimum benefit for that year under any defined benefit
                aggregation plan which is top-heavy shall, when expressed as a
                percentage of the affected participant's compensation, be equal
                to the lesser of:

               (a)   3%; or

               (b)   the percentage at which employer contributions (including
                     for plan years beginning after December 31,
                     1988, employer contributions made pursuant to
                     a cash or deferred arrangement) and
                     forfeitures are allocated to the accounts of
                     the key employee for whom such percentage
                     (when expressed as a percentage of
                     compensation) is greatest.

                For purposes of the preceding sentence, compensation earned
                while a member of a group of employees to whom the plan has not
                been extended shall be disregarded. Paragraph (b) next above
                shall not be applicable for any plan year if the plan enables a
                defined benefit plan described in paragraph A-9(a) or A-9(b) to
                meet the requirements of section 401(a)(4) or 410 for that year.
                Employer contributions for any plan year during which the plan
                is top-heavy shall be allocated first to non-key employees until
                the requirements of this subsection A-13 have been met and, to
                the extent necessary to comply with the provisions of this
                subsection A-13, additional contributions shall be required of
                the employers.

                                        A-1
<PAGE>

                                  SUPPLEMENT B
                                       TO
                   NICOR COMPANIES SAVINGS INVESTMENT PLAN
                                (ESOP Provisions)


Effective Date  B-1. The effective date of this Supplement B to the Nicor
                Companies Savings Investment Plan and the ESOP to which it
                relates is July 1, 1997.

Purpose         B-2. The purpose of this Supplement B is to set forth the
                provisions of the plan applicable to the ESOP and not set forth
                elsewhere in the plan.

Definitions     B-3. Unless the context clearly implies or indicates the
                contrary, a word, term or phrase used or defined in the plan is
                similarly used or defined for purposes of this Supplement B.

Allocation of
Nicor Stock     B-4. As of each accounting date coincident with or following
                the effective date of the ESOP, shares of Nicor stock held
                in the ESOP shall be allocated as set forth in
                subsection 7.1 to the accounts of participants who have elected
                to invest all or a portion of their accounts in the Nicor Stock
                Fund pursuant to an election described in subsection 6.2.

Distribution of  B-5.  An amount equal to the cash dividends paid on
Cash Dividends   or after the effective date of the ESOP on shares
                 of Nicor stock held by the trustee in the Nicor Stock Fund
                 shall be distributed, in cash, as soon as practicable after the
                 accounting date ending the accounting period in which the
                 dividends are paid to the trustee (but in no event more than 90
                 days after the close of the plan year in which the dividends
                 are paid to the trustee) to participants (or, in the event of
                 the participant's death, to the participant's beneficiary) in
                 accordance with the provisions of subsection 7.1. Distributions
                 under this subsection B-5 shall not require the consent of the
                 participant or any other person, shall not be subject to the
                 restrictions on pre-termination withdrawals described in
                 Section 11, and shall not be considered an eligible rollover
                 distribution for purposes of subsection 10.19.

Distributions    B-6.  Distributions or withdrawals in accordance
and              with Section 10 or 11 to or on behalf of any
Withdrawals      participant or beneficiary from the Nicor Stock
                 Fund shall be made in cash, except that the participant (or, in
                 the event of his death, his beneficiary) may elect to receive,
                 in lieu of cash, the distribution or withdrawal from his
                 account invested in such investment fund in the form of whole
                 shares of Nicor stock and cash equal to the fair market value
                 of any fractional share of Nicor stock. The amount of cash and
                 the number of whole shares of Nicor stock so distributed or
                 withdrawn shall be determined in accordance with the applicable
                 provisions of subsections 7.1 and 10.10 of the plan, treating
                 the accounting date as of which such distribution or withdrawal
                 is made as the distribution date for this purpose.

Diversification  B-7. Consistent with the diversification requirements of
                 section 401(a)(28) of the code, a participant may elect to
                 diversify all or a portion of his account which is invested in
                 the Nicor Stock Fund by filing an investment election pursuant
                 to subsection 6.3 of the plan.

Put Options     B-8.  If Nicor stock held under the ESOP is not
                readily tradable on an established securities
                market (within the meaning of section 409(h)(1)(B)
                of the code), any participant or beneficiary who
                is entitled to a distribution of such shares from
                the plan shall have a right to require the company
                to repurchase such shares in accordance with
                section 409(h)(1)(B) of the code.  Nicor stock
                held under the ESOP shall not be subject to a put,
                call, or other option, or a buy-sell or similar
                arrangement either while held by the plan or when
                distributed to or on account of a participant,
                whether or not the plan is then an employee stock
                ownership plan.

ESOP Loan       B-9.  If the plan is amended to cause it to enter
                into an ESOP Loan, as defined at Treas. Reg.
                Section 54.4975-7, any assets acquired by the plan
                with the proceeds of an ESOP Loan shall be added
                to and maintained in a suspense account in
                accordance with Treas. Reg. Sections
                54.4975-7(b)(8) and (15) and Section 54.4975-11.

Appraiser       B-10. If at any time the Nicor stock held by the plan is not
                readily tradable on an established securities market, all
                valuations of such stock with respect to activities carried on
                by the plan will be made by an independent appraiser meeting the
                requirements of section 401(a)(28) of the code.

Voting of       B-11. To the extent consistent with the trustee's
Nicor Stock     fiduciary obligations under ERISA, the Nicor stock
                held in the Nicor Stock Fund shall be voted by the trustee as
                follows:

               (a)   Within a reasonable time before each annual or special
                     meeting of shareholders of Nicor, the company
                     shall cause to be provided to each
                     participant whose accounts are invested in
                     the Nicor Stock Fund a copy of the proxy
                     soliciting material for the meeting, together
                     with a form requesting instructions to the
                     trustee as to how to vote the number of whole
                     shares of Nicor stock credited to such
                     participant's accounts.  The voting
                     instructions received by the trustee shall be
                     held by it in confidence.

               (b)   Upon timely receipt of such instructions, the trustee shall
                     vote the shares of Nicor stock for which it does not
                     receive voting instructions, and all other shares held by
                     the trustee in the Nicor Stock Fund, in the same proportion
                     as it votes shares with respect to which it has received
                     voting instructions, unless the trustee determines that to
                     do so would be inconsistent with Title I of ERISA.

                                   B-1
<PAGE>


                           FIRST AMENDMENT OF
                 NICOR COMPANIES SAVINGS INVESTMENT PLAN

      By virtue and in exercise of the amending power reserved to Northern
Illinois Gas Company (the "Company") by the terms of the Nicor Companies Savings
Investment Plan (the "Plan") and pursuant to the authority delegated to the
undersigned officers of the Company adopted on March 10, 1982, the Plan is
hereby amended effective as of January 1, 2001, in the following particulars:

1. By substituting the following for subsection 8.9 of the Plan:

      "8.9 Code Section 401(k)(3) Testing. The difference between (i) the
average of the deferral percentages (as defined below) of each eligible employee
who is highly compensated for the plan year (referred to hereinafter as the
`highly compensated group deferral percentage'), and (ii) the average of the
deferral percentages for the plan year of each eligible employee who was not
highly compensated for such plan year (referred to hereinafter as the
`non-highly compensated group deferral percentage') shall satisfy one of the
tests set forth in section 401(k)(3)(A)(ii) of the code. The `deferral
percentage' for any eligible employee for a plan year shall be determined by
dividing the amount of the employee tax-deferred contributions made with respect
to the participant for such year by his section 415 compensation for the year,
subject to the following special rules:

      (a)  the deferral percentage of an eligible employee who makes no employee
           tax-deferred contributions for the year shall be counted as zero;

      (b)  the deferral percentage for any eligible employee who is highly
           compensated and who is eligible to make elective deferrals under one
           or more other plans maintained by an employer or affiliate for a plan
           year of such other plan that ends with or within the same calendar
           year as the plan year (other than a plan or arrangement subject to
           mandatory disaggregation under applicable Treasury regulations) shall
           be determined as if all such elective deferrals were made on his
           behalf under the plan;

      (c)  excess employee tax-deferred contributions distributed to a
           participant under subsection 8.8 shall be counted in determining such
           participant's deferral percentage except in the case of a
           distribution to a non-highly compensated participant required to
           comply with section 401(a)(30) of the code; and

      (d)  in the event that this plan satisfies the requirements of sections
           401(k), 401(a)(4), or 410(b) of the code only if aggregated with one
           or more other plans having the same plan year, or if one or more
           other plans having the same plan year as this plan satisfy the
           requirements of such sections of the code only if aggregated with
           this plan, then this subsection 8.9 shall be applied as if all such
           plans were a single plan.

Application of this subsection 8.9 shall be consistent with the provisions of
section 401(k)(3) of the code and the regulations thereunder. The provisions of
this subsection 8.9 shall be deemed to be satisfied for any plan year if the
requirements of section 401(k)(12) of the code are satisfied."

2. By substituting the following for subsection 8.11 of the Plan:

      "8.11. Code Section 401(m)(2) Testing. For any plan year, the difference
between (i) the average of the contribution percentages (as defined below) of
each eligible employee who is highly compensated for the plan year (referred to
hereinafter as the `highly compensated group contribution percentage'), and (ii)
the average of the contribution percentages for the plan year of each eligible
employee who was not highly compensated for such plan year (referred to
hereinafter as the `non-highly compensated group contribution percentage') shall
satisfy one of the tests set forth in section 401(m)(2)(A) of the code. The
`contribution percentage' for any eligible employee for a plan year shall be
determined by dividing the sum of his employee after-tax contributions and the
employer matched contributions made for him for the year by his section 415
compensation for the year, subject to the following special rules:

      (a)  the contribution percentage of each eligible employee with respect to
           whom no employee after-tax contributions and employer matched
           contributions are made for the year shall be counted as zero;

      (b)  the contribution percentage for any eligible employee who is highly
           compensated and who is eligible to participate in one or more other
           qualified plans maintained by an employer or affiliate under which
           employee after-tax contributions or matching contributions may be
           made by or for him shall be determined as if all such contributions
           were made by or for him under the plan; and

      (c)  in the event that this plan satisfies the requirements of sections
           401(m), 401(a)(4), or 410(b) of the code only if aggregated with one
           or more other plans having the same plan year, or if one or more
           other plans having the same plan year as this plan satisfy the
           requirements of such sections of the code only if aggregated with
           this plan, then this subsection 8.11 shall be applied as if all such
           plans were a single plan.

Application of the provisions of this subsection 8.11 shall be consistent with
the provisions of section 401(m) of the code and the regulations thereunder. The
provisions of this subsection 8.11 shall be deemed to be satisfied with respect
to employer matched contributions (and such contributions shall not be taken
into account for purposes of applying the foregoing provisions of this
subsection 8.11) for any plan year if the requirements of section 401(m)(11) of
the code are satisfied."


      IN WITNESS WHEREOF, the undersigned officer has caused these presents to
be signed on behalf of the Company this 13th day of March, 2002.



                                    Northern Illinois Gas Company

                                    By:  /s/ Claudia Colalillo
                                    Its: Vice President Human Resources and
                                         Corporate Commununications

<PAGE>
                           SECOND AMENDMENT OF
                 NICOR COMPANIES SAVINGS INVESTMENT PLAN

By virtue and in exercise of the amending power reserved to Northern Illinois
Gas Company (the "Company") by the terms of the Nicor Companies Savings
Investment Plan (the "Plan") and pursuant to the authority delegated to the
undersigned officers of the Company adopted on March 10, 1982, the Plan is
hereby amended in the following particulars, all effective as of June 1, 2002
unless otherwise specified:

1. By substituting the following for subsections 10.4, 10.5, 10.6 and 10.7,
respectively, of the Plan:

      "10.4. Manner of Payment. Subject to the provisions of this Section 10, a
participant's accounts shall be distributed to or for the benefit of the
participant, or in the event of his death, to or for the benefit of his
beneficiary, by payment in a lump sum; provided, however that a participant
whose termination date occurs under paragraph 9(a) and the beneficiary of a
participant whose termination date occurs under paragraph 9(a) or 9(b) may elect
distribution of the participant's account by one of the following methods:

      (a)  By payment in a lump sum. OR

      (b)  By payment in a series of substantially equal annual, semi-annual,
           quarterly or monthly installments over a period not exceeding the
           payee's life expectancy. OR

      (c)  For distributions with a distribution date prior to June 1, 2002, by
           purchase from the insurer and distribution to the payee of an
           annuity, subject to the following:

(i)            Methods of payment shall be limited to (1) a single life annuity
               (as defined in subsection 10.5); (2) a joint and survivor
               annuity (as defined in subsection 10.5); (3) a single life
               annuity with a refund feature; and (4) a single life annuity
               with a fifteen year period certain feature.

(ii)           An annuity benefit may be of the fixed or variable type under
               which annuity payments will commence as of the participant's
               distribution date. The premium paid to the insurer for an
               annuity will be charged to the participant's accounts when paid.
               The committee shall cause the annuity to be delivered to the
               person or persons entitled to payments under it in a
               nontransferable and noncommutable form.

(iii)          Payments under the annuity shall satisfy the requirements of
               section 401(a)(9) of the code and the regulations thereunder,
               including the incidental death benefit requirement.

If a participant dies after distribution of his accounts have commenced in the
form described in paragraph (b) next above, the remaining portion of the
participant's account balances shall be distributed to or for the benefit of his
beneficiary in accordance with the distribution method in effect on the date of
the participant's death; provided, however, that the beneficiary may elect to
accelerate payment of such benefits.

      10.5. Payment in and Waiver of Joint and Survivor Annuity Form and Single
           Life Annuity Form. The provisions of this subsection 10.5 shall have
           no application for distributions with a distribution date occurring
           on or after June 1, 2002. If a participant's distribution date is
           prior to June 1, 2002 and the participant elects to have his account
           balances paid in accordance with paragraph 10.4(c), his account
           balances shall be applied to purchase a contract from an insurance
           company providing for payment in the form of a joint and survivor
           annuity (as defined below) if the participant is legally married
           under the laws of any jurisdiction on his distribution date, and in
           the form of a single life annuity (as described below) if the
           participant is unmarried on his distribution date, subject to the
           following provisions of this subsection 10.5. During an "election
           period" commencing no less than 30 days after the participant
           receives the election information described in subsection 10.7 and no
           more than 90 days before the participant's distribution date, a
           participant may waive payment in the joint and survivor annuity form
           (or single life annuity form in the case of an unmarried participant)
           and elect payment in one of the other forms permitted by subsection
           10.4. If a participant is legally married on his distribution date,
           then the waiver described in the preceding sentence will be effective
           only with spousal consent (as described in subsection 10.17). A
           participant may, at any time during his election period, revoke any
           prior waiver of the joint and survivor annuity form or single life
           annuity form, in which case his account balances shall be paid in the
           form of a joint and survivor annuity or a single life annuity, as
           applicable, in accordance with the foregoing provisions of this
           subsection 10.5. The term "joint and survivor annuity" means an
           annuity for the life of the participant with a survivor annuity for
           the life of his surviving spouse which is equal to 50 percent of the
           amount of the annuity payable during the joint lives of the
           participant and his spouse and which is the actuarial equivalent of a
           single life annuity for the life of the participant. The term "single
           life annuity" means an annuity payable for the payee's lifetime only.

      10.6. Payment in Form of Pre-Retirement Surviving Spouse Annuity. The
           provisions of this subsection 10.6 shall have no application for
           distributions with a distribution date occurring on or after June 1,
           2002. If a participant dies after electing to have his account
           balances distributed in accordance with paragraph 10.4(c) but prior
           to his distribution date, if the participant's distribution date is
           prior to June 1, 2002, and if such participant is legally married
           under the laws of any jurisdiction on the date of his death, the
           entire balance in his accounts shall be applied to purchase a
           contract from an insurance company providing for payment in the form
           of a pre-retirement surviving spouse annuity (as described below),
           which contract shall be distributed to the participant's surviving
           spouse. The term "pre-retirement surviving spouse annuity" means an
           annuity payable to the surviving spouse for life. Distribution of the
           contract providing for the pre-retirement surviving spouse annuity
           shall be made, and payment under such contract shall commence, as of
           the accounting date which is coincident with, or next following the
           later of the participant's termination date or the 65th anniversary
           date of the participant's birth; provided, however, that the
           surviving spouse may elect to receive the pre-retirement surviving
           spouse annuity contract, and to commence receipt of payments under
           such contract, within a reasonable time following the participant's
           death. A participant's surviving spouse who is eligible for a
           pre-retirement surviving spouse annuity in accordance with the
           foregoing provisions of this subsection 10.6 may waive payment in
           that form and elect payment in any form permitted by subsection 10.4
           by filing an election with the committee after the participant's
           death.

      10.7. Election Information. The provisions of this subsection 10.7 shall
           have no application for distributions with a distribution date
           occurring on or after June 1, 2002. As soon as practicable after a
           participant elects to have his account balances paid to him in
           accordance with paragraph 10.4(c) (but in no event less than 30 days
           nor more than 90 days before the participant's distribution date
           occurs), the committee will provide the participant with election
           information consisting of:

      (a)  a written description of the joint and survivor annuity or single
           life annuity, as the case may be, and the relative financial effect
           of payment of his account balances in the respective form;

      (b)  a notification of the right to waive payment in that form and the
           spouse's right, if applicable, with respect to that waiver;

      (c)  a notification of the participant's right to rescind a prior
           revocation of distribution in the form of a joint and survivor
           annuity and the effect thereof; and

      (d)  a general description of the eligibility conditions and other
           material features of the optional forms of distribution under the
           plan and information explaining the relative values of such optional
           forms of distribution.

The committee may make such election information available to a participant by:

      (1)  personal delivery to him;

      (2)  first-class mail, postage prepaid, addressed to the participant at
           his last known address as shown on the employer's records; or

      (3)  permanent posting on a bulletin board located at the participant's
           work site.

A participant may request, by notice filed with the committee during his
election period, an explanation, written in nontechnical language, of the terms,
conditions and financial effect (in terms of dollars per monthly benefit
payment) of payment in the joint and survivor annuity form or single life
annuity form. If not previously provided to the participant, the committee shall
provide him with such explanation within 30 days of his request by one of the
methods described in paragraphs (1) or (2) next above, and the participant's
election period will be extended, if necessary, to include the 90th day next
following the date on which he receives such explanation."

2. By substituting the following for paragraph 10.8(b) of the Plan:

      "(b) Subject to the following provisions of this subsection 10.8, a
           participant may elect to have distribution of his account balances
           commence in the form of a lump sum or, if the distribution date
           occurs prior to June 1, 2002, an annuity, as of any date that is
           coincident with or following his termination date and prior to his
           age 70-1/2; provided, however, that a person who was a participant in
           the plan on April 1, 1998 and whose termination date occurs under
           paragraph 9(a) may elect to have his account balances commence in any
           form of payment permitted under the terms of the plan; and provided
           further that, if a participant does not make an election in
           accordance with this paragraph (b) within 90 days of his termination
           date, he shall be deemed to have elected to defer distribution of his
           account balances until the earlier of (i) the date that he
           subsequently elects to commence distribution, or (ii) the date on
           which he attains age 70-1/2."

3. By substituting the following for subsection 10.17 of the Plan:

      "10.17. Spousal Consent. Any election by a participant under the plan
which, by its terms, requires spousal consent, shall be effective only if (i)
the participant's spouse consents in writing to such election; (ii) the consent
acknowledges the effect of the election and is witnessed by a notary public (or,
if permitted by the committee, a plan representative appointed or approved by
the committee); (iii) in the case of a spousal consent to a beneficiary
designation election, such election designates a specific beneficiary which may
not be changed without spousal consent; and (iv) in the case of a participant's
waiver of a joint and survivor annuity, if the participant's distribution date
is prior June 1, 2002 and prior to his 65th birthday, the spouse consents to the
time of payment and the spouse consents to the optional form of payment elected
by the participant; provided, however, that unless otherwise provided by a
qualified domestic relations order within the meaning of section 414(p) of the
code, no such consent shall be required if:

      (a)  the participant and his spouse are legally separated or the
           participant has been abandoned (within the meaning of local law) and
           the participant has a court order to such effect; or

      (b)  it is established to the satisfaction of a plan representative
           appointed or approved by the committee that the consent of the
           participant's spouse cannot be obtained because there is no spouse,
           because the spouse cannot be located or because of such other
           circumstances as the Secretary of the Treasury may prescribe in
           regulations."

<PAGE>

      IN WITNESS WHEREOF, the undersigned officer has caused these presents to
be signed on behalf of the Company as of the 1st day of June, 2002.



                                    Northern Illinois Gas Company

                                    By:/s/ Claudia J. Colalillo
                                    Its Senior Vice President
                                        Human Resources & Customer Care


<PAGE>


                           THIRD AMENDMENT OF
                 NICOR COMPANIES SAVINGS INVESTMENT PLAN

By virtue and in exercise of the amending power reserved to Northern Illinois
Gas Company (the "Company") by the terms of the Nicor Companies Savings
Investment Plan (the "Plan") and pursuant to the authority delegated to the
undersigned officers of the Company adopted on March 10, 1982, the Plan is
hereby amended in the following particulars, all effective as of January 1, 2002
unless otherwise specified, which amendments are intended as good faith
compliance with the requirements of the Economic Growth and Tax Relief
Reconciliation Act of 2001 ("EGTRRA") and are to be construed in accordance with
EGTRRA and guidance issued thereunder:

1. By substituting the following for subsection 4.1 of the Plan:

      "4.1. Employee Tax-deferred Contributions. Subject to the following
provisions of this Section 4 and Section 8, each employer, out of its current or
accumulated profits (as determined in accordance with recognized accounting
principles and practices), shall contribute to the trustee, in cash, on behalf
of each participant for whom a tax deferral election is in effect as to any pay
period, an amount, referred to herein as an `employee tax-deferred
contribution', which is equal to the amount by which the compensation (as
defined in subsection 4.5) otherwise payable to the participant during that pay
period by the employer has been reduced pursuant to the terms of a tax deferral
election. For purposes of the plan, the term `tax deferral election' means an
election by an employee to have the amount of the compensation that would
otherwise be payable to him for each pay period during the period in which the
election is in effect reduced by an amount that is not less than 1 percent and
not more than 15 percent (or such other percent as the committee shall decide
and, in all cases, in multiples of one percent). The plan provisions relating to
certain limitations on employee after-tax contributions are set forth in
subsection 4.2. Employee tax-deferred contributions shall be paid to the trustee
in accordance with subsection 4.10."

2. Effective as of January 1, 2001, by substituting "5 percent" for "6 percent"
where the latter phrase appears in the penultimate sentence of subsection 4.3 of
the Plan."

3. By substituting the following for subsection 4.5 of the Plan:

      "4.5. Compensation. For purposes of the plan, a participant's
`compensation' for any period means the regular basic cash remuneration paid to
him for such period by reason of his employment with the employers as a
participant, excluding bonuses, overtime pay, and all other remuneration of any
kind including, but not limited to pre-paid salary increase advances and lump
sum raise payments, and including vacation pay, reductions made in accordance
with the provisions of subsection 4.1, reductions made pursuant to section 125
of the code, including under any tax exempt premium plan in which the employee
participates, and reductions made pursuant to section 132(f)(4) of the code;
provided, however, that the compensation of any participant for any plan year
shall be disregarded to the extent that it exceeds $200,000 (adjusted in
accordance with section 401(a)(17) of the code), taking into account any
proration of such amount as may be required under applicable Treasury
regulations on account of a short plan year. Notwithstanding the foregoing, the
`compensation' as applied to any participant who is employed by NHS shall mean,
for any period prior to March 1, 2002, the total cash remuneration paid to him
for such period by reason of his employment with NHS (not in excess of the
limitations imposed by section 401(a)(17) of the code), including reductions
made in accordance with the provisions of subsection 4.1, reductions made
pursuant to section 125 of the code, including under any tax exempt premium plan
in which the employee participates, and reductions made pursuant to section
132(f)(4) of the code."

4. By substituting the following for subsection 4.11 of the Plan:

      "4.11. Rollover Contributions. An employee who satisfies the requirements
of subsection 2.1 of the plan and who is actively employed by an employer and
any participant who is actively employed by an employer or an affiliate may,
with the consent of the committee, make a rollover contribution (as defined
below) to the trustee of the plan. The term `rollover contribution' means:

      (a)  a cash contribution to the plan by the participant of amounts
           distributed from an eligible plan (as defined below) or distributed
           from an individual retirement account and constituting a `rollover
           contribution' as described in section 408(d)(3) of the code and made
           within 60 days of receipt of such amount; or

      (b)  a cash payment made to the plan by another qualified plan described
           in section 401(a) of the code as a direct rollover (as contemplated
           by section 401(a)(31) of the code) on behalf of and at the direction
           of the participant,

provided such distributed or directly rolled over amounts are permitted to be
rolled over to a qualified plan under the applicable provisions of the code as
then in effect and such amounts do not consist of after-tax employee
contributions or other amounts which would not otherwise be includible in gross
income. For purposes of this subsection 4.5, an `eligible plan' shall mean a
qualified plan described in section 401(a) or 403(a) of the code, an annuity
contract described in section 403(b) of the code, an eligible plan under section
457(b) of the code which is maintained by a state, political subdivision of a
state, or any agency or instrumentality of a state or political subdivision of a
state, or an individual retirement account or annuity described in section
408(a) or 408(b) of the code. The committee may request from the participant
such documents as it considers necessary or desirable to establish that the
rollover contribution satisfies the foregoing requirements. The portion of a
participant's interest under the plan which is attributable to his rollover
contributions shall be fully vested and nonforfeitable at all times. An employee
who has made a rollover contribution but who is not a participant in the plan
will be treated as a participant solely with respect to the amounts credited to
his rollover account under the plan (as described in Section 5)."

5. Effective as of January 1, 2001, by substituting the following for
subsection 7.2 of the Plan:

      "7.2. Deduction, Crediting and Allocation of Contributions and Dividends.
Subject to the provisions of Section 8:

      (a)  Employee tax-deferred contributions, employee after-tax contributions
           and rollover contributions on behalf of a participant for any period
           shall be credited to that participant's appropriate accounts as of
           the day on which such contributions are made.

      (b)  The amount of the employer matched contributions that are made on
           behalf of a participant shall be credited, as of the end of the day
           that the contributions are made, to the participant's employee
           tax-deferred account and employee after-tax account, pro rata,
           according to the rate of employee tax-deferred contributions and
           employee after-tax contributions that are made with respect to the
           participant, respectively; provided, however, that, if the sum of a
           participant's employee tax-deferred contribution rate and employee
           after-tax contribution rate exceeds 6 percent of the participant's
           compensation, then the amount of the employer matched contributions
           made with respect to the participant shall be credited to the
           participant's employee tax-deferred account in the same ratio that
           the participant's employee tax-deferred contribution rate (not in
           excess of 6 percent) bears to 6 percent, and the amount of any
           remaining employer matched contributions shall be credited to the
           participant's employee after-tax account.

      (c)  As of the last day of each plan year the employer profit sharing
           contributions of each employer for that plan year shall be allocated
           among and credited to the profit sharing accounts of profit sharing
           participants who were employed by the employer on the last day of the
           plan year, pro rata based on the compensation paid to them from the
           employer for that plan year.

      (d)  As of any accounting date which is also a dividend payment date,
           shares of Nicor stock received by the trustee as a result of a stock
           split or stock dividend shall be allocated among and credited to the
           accounts of participants whose accounts were invested in the Nicor
           stock fund as of the dividend record date to which the dividend
           payment date relates, pro rata based on the number of shares of Nicor
           stock held in the Nicor Stock fund as of the dividend record date.

      (e)  As of any accounting date which is also a dividend payment date, cash
           dividends paid on shares of Nicor stock which were held in the Nicor
           stock fund as of the dividend record date to which the dividend
           payment date relates shall be distributed to participants in
           accordance with Supplement B of the plan; provided, however, that,
           for periods on an after May 1, 2002, the trustee shall use all cash
           dividends with respect to which participants have not elected a cash
           distribution pursuant to Supplement B to purchase shares of Nicor
           stock. Shares of Nicor stock purchased pursuant to the preceding
           sentence will be allocated and credited to the accounts of
           participants whose accounts were invested in the Nicor stock fund as
           of the dividend record date and who did not elect a cash distribution
           of dividends pursuant to Supplement B, pro rata based on the number
           of shares purchased by the trustee with the cash dividends.

For purposes of this Section 7, all employer contributions for any plan year
which are made after the close of the plan year will be considered to have been
made on the last day of that plan year regardless of when paid to the trustee."

6. By substituting the following for subsections 8.2 and 8.3, respectively, of
the Plan:

      "8.2. Compensation for Limitation/Testing Purposes. For purposes of the
plan, the term `section 415 compensation' for any plan year means the
participant's compensation (as described in Treas. Reg. Section 1.415-2(d)(1))
paid during that year for personal services actually rendered in the course of
employment with any employer or any section 415 affiliate, excluding deferred
compensation and other amounts that receive special tax treatment (as described
in Treas. Reg. Section 1.415-2(d)(2)) but including any elective contributions
made on the participant's behalf for the year under the plan or any plan
maintained by an employer or affiliate which are excludable from the
participant's gross income by reason of section 125, 402(e)(3) and 132(f)(4) of
the code. Notwithstanding the foregoing provisions of this subsection 8.2,
`section 415 compensation' for any plan year shall be disregarded to the extent
that it exceeds $200,000 (adjusted in accordance with section 401(a)(17) of the
code), taking into account any proration of such amount as may be required under
applicable Treasury regulations where section 415 compensation is computed with
respect to a period of less than a full year (other than on account of mid-year
commencement or cessation of active participation in the plan).

      8.3. Limitations on Annual Additions. Notwithstanding any other provision
           of the plan other than the provisions of this Section 8, a
           participant's annual additions (as defined below) for any plan year
           shall not exceed an amount equal to the lesser of:

      (a)  $40,000 (as adjusted for each plan year to take into account any
           applicable cost-of-living adjustment for that year provided by the
           Secretary of the Treasury under section 415(d) of the code); or

      (b)  100 percent of the section 415 compensation paid to the participant
           in that plan year (determined without regard to the limitations of
           section 401(a)(17) of the code).

The limitations set forth under paragraphs (a) and (b) shall be adjusted to the
extent required by subsection 8.4. For purposes of the plan, the term `annual
additions' means, with respect to any participant for any plan year, the sum of
the following amounts, determined without regard to whether any such amounts (or
portions thereof) are subsequently distributed to the participant in accordance
with the provisions of subsection 8.8, 8.10, 8.12 or 8.13:

      (1)  employer contributions and forfeitures (including employee
           tax-deferred contributions which are considered to be employer
           contributions) credited to the participant's accounts for that plan
           year under this plan and each related defined contribution plan (as
           defined below);

      (2)  employee contributions (other than rollover contributions) credited
           to the participant's accounts under this plan and each related
           defined contribution plan for that plan year; and

      (3)  employer contributions allocated to any individual medical account
           (as described in section 415(l) of the code) that is maintained for
           the benefit of the participant under a related defined benefit plan
           (as defined below) and, if the participant is a key employee (as
           defined in Supplement A), any amount allocated to a related medical
           account (as defined below) maintained for the participant; provided,
           however, that the amounts described in this paragraph (3) shall be
           disregarded for purposes of the limitation set forth in paragraph (b)
           next above.

For purposes of the plan: (i) the term `related medical account' means any
account maintained by any employer or section 415 affiliate under section
419A(d) of the code to fund retiree medical benefits; (ii) the term `section 415
affiliate' means any corporation or trade or business that is, along with any
employer, a member of a controlled group of corporations or controlled group of
trades or businesses (as described in sections 414(b) and (c) of the code, as
modified by section 415(h) thereof); and (iii) the term `related defined
contribution plan' and `related defined benefit plan' mean any other defined
contribution plan and any defined benefit plan (both as defined in section
415(k) of the code), respectively, maintained by any employer or section 415
affiliate."

7. By adding the following as the last sentence of subsection 8.13 of the Plan:

"The provisions of this subsection 8.13 shall not apply for plan years beginning
after December 31, 2001."

8. By substituting the following for paragraphs (c) and (d) of Section 9 of the
Plan:

      "(c) Vested Resignation or Dismissal. The participant resigns or is
           dismissed from the employ of the employers and the affiliates before
           retirement in accordance with paragraph (a) next above but after
           completing at least 3 years of service (5 years of service if the
           participant does not have at least one hour of service after December
           31, 2001).

      (d)  Non-Vested Resignation or Dismissal. The participant resigns or is
           dismissed from the employ of the employers and the affiliates before
           retirement in accordance with paragraph (a) next above and prior to
           completing at least 3 years of service (5 years of service if the
           participant does not have at least one hour of service after December
           31, 2001)."

9. By substituting the following for subsections 10.19 and 10.20, respectively,
of the plan:

      "10.19 Direct Rollover to an Eligible Retirement Plan. Notwithstanding any
provision of the plan to the contrary that would otherwise limit a distributee's
election under this subsection 10.19, a distributee may elect, at the time and
in the manner prescribed by the committee, to have any portion of an "eligible
rollover distribution" (as defined in section 402(c)(4) of the code) paid
directly to an eligible retirement plan specified by the distributee in a direct
rollover. For purposes of this subsection 10.19, the following definitions shall
apply:

      (a)  An `eligible rollover distribution' means 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; and any
           distribution to the extent such distribution is required under
           section 401(a)(9) of the code. A portion of a distribution shall not
           fail to be an eligible rollover distribution merely because the
           portion consists of after-tax employee contributions which are not
           includible in gross income; provided, however, that such portion may
           be transferred only to an individual retirement account or annuity
           described in section 408(a) or (b) of the code, or to a qualified
           defined contribution plan described in section 401(a) or 403(a) of
           the code that agrees to separately account for amounts so
           transferred, including separately accounting for the portion of such
           distribution which is includible in gross income and the portion of
           such distribution which is not so includible. A hardship withdrawal
           shall not constitute an eligible rollover distribution for purposes
           of the Plan.

      (b)  An `eligible retirement plan' means an individual retirement account
           described in section 408(a) of the code, an individual retirement
           annuity described in section 408(b) of the code, an annuity plan
           described in section 403(a) of the code, or a qualified trust
           described in section 401(a) of the code that accepts the
           distributee's eligible rollover distribution. For distributions
           occurring after December 31, 2001, an `eligible retirement plan' also
           includes an annuity contract described in section 403(b) of the code
           or an eligible plan under section 457(b) of the code which is
           maintained by a state, political subdivision of a state, or any
           agency or instrumentality of a state or political subdivision of a
           state and which agrees to separately account for amounts transferred
           into such plan from the Plan. The definition of eligible retirement
           plan shall also apply in the case of a distribution to a surviving
           spouse, or to a spouse or former spouse who is the alternate payee
           under a qualified domestic relations order, as defined in section
           414(p) of the code.

      (c)  A `distributee' means an employee or former employee and 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
           section 414(p) of the code.

      (d)  A `direct rollover to an eligible retirement plan' means a payment by
           the plan to the eligible retirement plan specified by the
           distributee.

      10.20 Distribution Only Upon Separation From Service. Notwithstanding any
other provision of the plan to the contrary, for periods prior to January 1,
2002, a participant may not commence distribution of his employee tax-deferred
contribution account pursuant to this Section 10, even though he has otherwise
had a termination date under Section 9, unless or until he also has a
`separation from service' within the meaning of section 401(k)(2)(B) of the
code. The foregoing restriction shall not apply, however, if the participant's
termination date occurs in connection with the sale by an employer to an
unrelated corporation of at least 85 percent of the assets of a trade or
business, or the sale of its interest in a subsidiary to an unrelated entity,
provided (a) the participant remains employed in such trade or business or by
such subsidiary after the sale, (b) the employer continues to maintain the plan
after the sale, (c) no transfer of the participant's accounts occurs or is
scheduled to occur after the sale pursuant to subsection 14.3 to a plan of such
subsidiary or of the purchaser of such assets (or any entity affiliated
therewith), and (d) the participant receives distribution of his account
balances (less any outstanding loan balances) under the plan in a lump sum by
the end of the second calendar year after the year in which the sale occurs.
Effective as of January 1, 2002, the foregoing provisions of this subsection
10.20 not apply and a Participant shall be entitled to commence distribution
upon his severance from employment, subject to other provisions of the Plan
governing distributions, other than provisions which require a separation from
service before such amounts may be distributed. The preceding sentence shall
apply as of January 1, 2002, regardless of whether the Participant's severance
from employment occurred before January 1, 2002."

10. Effective as of January 1, 2003, by substituting the following for clause
11.3(a)(iii) of the Plan:

           "(iii) payment of tuition, related educational fees, and room and
                board expenses for up to the next 12 months of post-secondary
                education for the participant, or his spouse or dependents (as
                defined in section 152 of the code); or"

11. By adding the following new subsection A-14 to Supplement A of the Plan
immediately after Section A-13 thereof:

"Special Rules       A-14.  This subsection shall apply for
                     purposes of determining whether the plan is a
                     top-heavy plan under section 416(g) of the
                     code for plan years beginning after December
                     31, 2001, and whether the plan satisfies the
                     minimum benefits requirements of section
                     416(c) of the code for such years. To the
                     extent applicable, this subsection supersedes
                     the foregoing provisions of this Supplement A.
                     (a)  A `key employee' means any employee or former employee
                          (including any deceased employee) who at any time
                          during the plan year that includes the determination
                          date was an officer of the employers and affiliates
                          having annual compensation greater than $130,000 (as
                          adjusted under section 416(i)(1) of the code for plan
                          years beginning after December 31, 2002), a 5-percent
                          owner of the employers and affiliates, or a 1-percent
                          owner of the employer and affiliates having annual
                          compensation of more than $150,000. For this purpose,
                          annual compensation means compensation within the
                          meaning of section 415(c)(3) of the code. The
                          determination of who is a Key Employee will be made in
                          accordance with section 416(i)(1) of the code and the
                          applicable regulations and other guidance of general
                          applicability issued thereunder.
                     (b)  The following provisions shall apply for purposes of
                          determining the present values of accrued benefits and
                          the amounts of account balances of employees as of the
                          determination date.

                           (i) The present values of accrued
                               benefits and the amounts of account balances of
                               an employee as of the determination date shall be
                               increased by the distributions made with respect
                               to the employee under the plan and any plan
                               aggregated with the plan under section 416(g)(2)
                               of the code during the 1-year period ending on
                               the determination date. The preceding sentence
                               shall also apply to distributions under a
                               terminated plan which, had it not been
                               terminated, would have been aggregated with the
                               plan under section 416(g)(2)(A)(i) of the Code.
                               In the case of a distribution made for a reason
                               other than separation from service, death or
                               disability, this provision shall be applied by
                               substituting `5-year period' for `1-year period'.

                          (ii) Accrued benefits and accounts of any individual
                               who has not performed services for the employers
                               and affiliates during the 1-year period ending on
                               the determination date shall not be taken into
                               account.

                     (c)  Employer matching contributions shall be taken into
                          account for purposes of satisfying the minimum
                          contribution requirements of section 416(c)(2) of the
                          code and the plan. The preceding sentence shall apply
                          with respect to matching contributions under the plan
                          or, if the plan provides that the minimum contribution
                          requirement shall be met in another plan, such other
                          plan. Employer matching contributions that are used to
                          satisfy the minimum contribution requirements shall be
                          treated as matching contributions for purposes of the
                          actual contribution percentage test and other
                          requirements of section 401(m) of the code."

12. Effective as of January 1, 2001, by substituting the phrase "subsection 7.2"
for the phrase "subsection 7.1" where the latter phrase appears in subsection
B-4 of Supplement B of the Plan.

13. Effective as of May 1, 2002, by substituting the following for subsection
B-5 of Supplement B of the Plan:

"Treatment of    B-5. On and after May 1, 2002, any cash dividends
Cash Dividends   paid on shares of Nicor stock held by the trustee
                 in the Nicor Stock Fund shall be allocated and credited to
                 participants' accounts in accordance with subsection 7.2(e) of
                 the plan. Notwithstanding the foregoing, a participant (or in
                 the event his death, his beneficiary) may elect to have any
                 cash dividends paid on shares of Nicor stock held by the
                 trustee in the Nicor Stock Fund distributed, in cash, as soon
                 as practicable after the accounting date ending the accounting
                 period in which the dividends are paid to the trustee (but in
                 no event more than 90 days after the close of the plan year in
                 which the dividends are paid to the trustee). Distributions
                 under this subsection B-5 on and after May 1, 2002 shall not be
                 subject to the restrictions on pre-termination withdrawals
                 described in Section 11 and shall not be considered an eligible
                 rollover distribution for purposes of subsection 10.19."

<PAGE>


      IN WITNESS WHEREOF, the undersigned officer has caused these presents to
be signed on behalf of the Company this 20 day of December, 2002.



                                    Northern Illinois Gas Company

                                    By: /s/ Claudia J. Colalillo
                                    Its Senior Vice President
                                        Human Resources & Customer Care


<PAGE>


                           FOURTH AMENDMENT OF
                 NICOR COMPANIES SAVINGS INVESTMENT PLAN

By virtue and in exercise of the amending power reserved to Northern Illinois
Gas Company (the "Company") by the terms of the Nicor Companies Savings
Investment Plan (the "Plan") and pursuant to the authority delegated to the
undersigned officers of the Company adopted on March 10, 1982, the Plan is
hereby amended in the following particulars:

1. Effective as of January 26, 2003, by substituting the following for the last
sentence of subsection 6.2 of the Plan:

"Elections pursuant to this subsection 6.2 shall be made in accordance with
uniform and nondiscriminatory rules established from time to time by the
committee and shall be subject to such restrictions as the committee may impose
from time to time to comply with the provisions of applicable law, including
Sarbanes-Oxley Act of 2002 (`Sarbanes-Oxley')."

2. Effective as of January 26, 2003, by substituting the following for the last
sentence of subsection 6.3 of the Plan:

"A transfer shall be effective pursuant to uniform and nondiscriminatory rules
established from time to time by the committee and shall be subject to such
restrictions as the committee may impose from time to time to comply with the
provisions of applicable law, including Sarbanes-Oxley."

3. Effective as of August 1, 2002, by substituting the following for that
portion of subsection 11.4 of the Plan that precedes paragraph (a) thereof:

"A participant who is an employee of an employer or an affiliate or who is
otherwise required to be given the opportunity to borrow under applicable
regulations may, in accordance with uniform and nondiscriminatory rules
established by the committee and by following such procedures as the committee
may from time to time establish, request a loan to be made to him from his
accounts. Notwithstanding the foregoing, no loan shall be made to a participant
hereunder and any loan outstanding hereunder shall immediately become due and
payable if the committee determines that such loan (or the continuation of such
loan) would be a violation of applicable law, including Sarbanes-Oxley. All
loans under the plan shall be made in accordance with the following:"


      IN WITNESS WHEREOF, the undersigned officer has caused these presents to
be signed on behalf of the Company this 7 day of February, 2003.

                                    Northern Illinois Gas Company

                                    By:/s/ Claudia Colalillo
                                    Its: Senior Vice President
                                         Human Resources and Corporate
                                         Communications

<PAGE>


                           FIFTH AMENDMENT OF
                 NICOR COMPANIES SAVINGS INVESTMENT PLAN

      By virtue and in exercise of the amending power reserved to Northern
Illinois Gas Company (the "Company") by the terms of the Nicor Companies Savings
Investment Plan (the "Plan") and pursuant to the authority delegated to the
undersigned officers of the Company adopted on March 10, 1982, the Plan is
hereby amended effective as of January 1, 2001, in the following particulars:

1. By substituting the following for subsection 8.2 of the Plan:

      "8.2.Compensation for Limitation/Testing Purposes. For purposes of the
plan, the term "section 415 compensation" for any plan year means the
participant's compensation (as described in Treas. Reg. Section 1.415-2(d)(1))
paid during that year for personal services actually rendered in the course of
employment with any employer or any section 415 affiliate, excluding deferred
compensation and other amounts that receive special tax treatment (as described
in Treas. Reg. Section 1.415-2(d)(2)) but including any elective contributions
made on the participant's behalf for the year under the plan or any plan
maintained by an employer or affiliate which are excludable from the
participant's gross income by reason of section 125, 402(e)(3) and 132(f)(4) of
the code. Notwithstanding the foregoing provisions of this subsection 8.2,
"section 415 compensation" for any plan year shall be disregarded to the extent
that it exceeds $160,000 (adjusted in accordance with section 401(a)(17) of the
code), taking into account any proration of such amount as may be required under
applicable Treasury regulations where section 415 compensation is computed with
respect to a period of less than a full year (other than on account of mid-year
commencement or cessation of active participation in the plan)."



      IN WITNESS WHEREOF, the undersigned officer has caused these
presents to be signed on behalf of the Company this 7 day of February, 2003.



                                    Northern Illinois Gas Company

                                    By:/s/ Claudia Colalillo
                                    Its: Senior Vice President
                                         Human Resources and Corporate
                                         Communications