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                                                                    EXHIBIT 10.9

                         FIRST SUPPLEMENTAL PLAN TO THE
                         DYNEGY INC. SEVERANCE PAY PLAN

I.  INTRODUCTION

     Dynegy Inc., a Delaware corporation ("Dynegy"), and its participating
subsidiaries and affiliated entities have heretofore established the Dynegy Inc.
Severance Pay Plan (the "Plan").  The Plan specifically contemplates that
certain plans may be designated as supplements to the Plan.  This First
Supplemental Plan to the Dynegy Inc. Severance Pay Plan (the "First Supplemental
Plan") is hereby established as a supplement to the Plan on behalf of Dynegy and
all of its subsidiaries and affiliates that participate in the Plan.  The First
Supplemental Plan is intended to provide severance benefits to certain employees
whose employment is terminated involuntarily by the Company following a Change
in Control.  Such severance benefits shall be in lieu of the severance benefits,
if any, that would otherwise be provided under the Plan upon such involuntary
termination of employment.

II.  DEFINITIONS

     As used herein, the terms "Dynegy," "Plan," and "First Supplemental Plan"
shall have the meanings set forth in Section I hereof.  Capitalized terms used
in the First Supplemental Plan but not defined herein are defined in the Plan
and are used herein with the meanings ascribed to them in the Plan.  Where the
following words and phrases appear in the First Supplemental Plan, they shall
have the respective meanings set forth below, unless their context clearly
indicates to the contrary:

          A. "CHANGE IN CONTROL" shall mean the occurrence of any of the
     following events:

               (a) any "person" or "group" (as defined in or contemplated by
          Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934,
          as amended (the "Exchange Act")) is or becomes the "beneficial owner"
          (as defined in Rule 13d-3 under the Exchange Act), directly or
          indirectly, of more than 50% of the total voting stock of Dynegy;

               (b) Dynegy is merged with or into or consolidated with another
          person and, immediately after giving effect to the merger or
          consolidation, (1) less than 50% of the total voting power of the
          outstanding voting stock of the surviving or resulting person is then
          "beneficially owned" (within the meaning of Rule 13d-3 under the
          Exchange Act) in the aggregate by (x) the stockholders of Dynegy
          immediately prior to such merger or consolidation, or (y) if a record
          date has been set to determine the stockholders of Dynegy entitled to
          vote with respect to such merger or consolidation, the stockholders of
          Dynegy as of such record date and (2) any "person" or "group" (as
          defined in or contemplated by Section 13(d)(3) or 14(d)(2) of the
          Exchange Act) is or has become the direct or indirect "beneficial
          owner" (as defined in Rule 13d-3
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          under the Exchange Act) of more than 50% of the voting power of the
          voting stock of the surviving or resulting person;

               (c) Dynegy, either individually or in conjunction with one or
          more of its subsidiaries, sells, assigns, conveys, transfers, leases
          or otherwise disposes of, or the subsidiaries sell, assign, convey,
          transfer, lease or otherwise dispose of, all or substantially all of
          the properties and assets of Dynegy and the subsidiaries, taken as a
          whole (either in one transaction or a series of related transactions),
          to any person (other than Dynegy or a wholly owned subsidiary); or

               (d) the liquidation or dissolution of Dynegy;

     provided, however, that a "Change in Control" shall be deemed to have not
     occurred if Chevron Corporation or its subsidiaries and/or affiliates own,
     directly or indirectly, more than 50% of the total voting stock of Dynegy
     so long as (i) Chevron Corporation, its subsidiaries or affiliates reduce
     their interest to less than a 50% interest either (x) within six months
     after the date they acquire a greater than 50% interest, or (y) within an
     extended period of up to two years after the date they acquire a greater
     than 50% interest if such extension is approved by the affirmative vote of
     at least 11 members of the Board of Directors of Dynegy (or such lesser or
     greater number of directors as may be required by Section 3.10(b) of the
     Bylaws of Dynegy as such may be amended from time to time) prior to the end
     of the six-month period specified in clause (x) of this proviso, and (ii)
     Chevron Corporation does not materially alter the operations or management
     of Dynegy during such six-month or extended period.  In addition to the
     foregoing, a "Change in Control" shall be deemed to have occurred for all
     purposes of the First Supplemental Plan upon the consummation of the
     transactions contemplated in that certain Agreement and Plan of Merger
     dated as of June 14, 1999, by and among Illinova Corporation, Energy
     Convergence Holding Company, Energy Convergence Acquisition Corporation,
     Dynegy Acquisition Corporation, and Dynegy, as the same may be amended from
     time to time.

          B.  "CONTINUATION COVERAGE PERIOD" shall mean, with respect to each
     Participant, a period of time equal to the number of full and partial Years
     of Service upon which such Participant's lump sum cash payment provided
     pursuant to Section III.A.(a) hereof was based, subject to a minimum of
     four months and a maximum of 12 months.

          C.  "DISABILITY" shall mean a disability entitling a Participant to
     benefits under a group long-term disability plan maintained by the Company.

          D.  "INVOLUNTARY TERMINATION" shall mean, with respect to each
     Participant, any termination of such Participant's employment with the
     Company; provided, however, that the term "Involuntary Termination" shall
     not include a voluntary resignation by such Participant, a Termination for
     Cause, or any termination as a result of such Participant's death or
     Disability.

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          E.  "MONTH OF PAY" shall mean, with respect to each Participant, such
     Participant's base monthly rate of pay, excluding overtime, bonuses,
     commissions (except in the case of truck drivers whose base pay is
     comprised solely of commissions), premium pay, shift differentials,
     employee benefits, expense reimbursements, and similar amounts.  If a
     Participant is paid by the hour, then such Participant's base monthly rate
     of pay is (a) his or her regular hourly rate, multiplied by (b) his or her
     regularly scheduled hours per year, divided by (c) 12.  A Participant's
     base monthly rate of pay shall be determined based upon the highest rate in
     effect (1) immediately prior to the Change in Control, (2) 60 days prior to
     the date of such Participant's Involuntary Termination, or (3) the date of
     such Participant's Involuntary Termination.

          F.  "PARTICIPANT" shall mean each Employee other than an Employee who
     is a participant in any other supplement to the Plan or any other severance
     benefit plan maintained by the Company or any of its affiliates (other than
     the Plan).

          G.  "TERMINATION FOR CAUSE" shall mean any termination of a
     Participant's employment with the Company by reason of such Participant's
     (a) conviction of a misdemeanor involving moral turpitude or a felony, (b)
     engagement in conduct which is materially injurious (monetarily or
     otherwise) to the Company or any of its affiliates (including, without
     limitation, misuse of the Company's or an affiliate's funds or other
     property), (c) engagement in gross negligence or willful misconduct in the
     performance of such individual's duties, (d) willful refusal without proper
     legal reason to perform such individual's duties and responsibilities, (e)
     material breach of any material provision of any agreement between the
     Company and such individual, or (f) material breach of any material
     corporate policy maintained and established by the Company that is of
     general applicability to Participants.

III. SEVERANCE BENEFITS

     A.   SEVERANCE BENEFITS.

          If the employment by the Company or a successor thereto of a
Participant shall be subject to an Involuntary Termination that occurs on the
date upon which a Change in Control occurs or within one year thereafter, then
such Participant shall be entitled to receive, subject to the provisions of
Section III.B. hereof, the following severance benefits:

          (a) a lump sum cash payment in an amount equal to one Month of Pay for
     each full, completed Year of Service  and a pro-rated amount for less than
     a Year of Service, subject to a minimum of four Months of Pay and a maximum
     of 12 Months of Pay; and

          (b)  such Participant and those of his or her dependents (including
     such Participant's spouse) who were covered under the medical and life
     insurance benefit plans maintained by the Company on the day prior to such
     Involuntary Termination shall continue to be covered under such plans
     throughout the Continuation Coverage Period beginning on the date of such
     Involuntary Termination at a cost to such Participant that is no greater
     than

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     the cost of such coverage paid by such Participant immediately prior to
     such Involuntary Termination; provided, however, that coverage under a
     particular medical or life insurance benefit plan shall immediately end
     upon such Participant's obtainment of new employment and coverage under a
     similar welfare benefit plan maintained by such Participant's new employer
     (with such Participant being obligated hereunder to promptly report such
     new coverage to the Company). Nothing herein shall be deemed to adversely
     affect in any way the additional rights, after consideration of this
     extension period, of such Participant and his or her eligible dependents to
     health care continuation coverage as required pursuant to Part 6 of Title I
     of ERISA.

     B.   ADDITIONAL TERMS; MITIGATION.

          The First Supplemental Plan and the severance benefits described in
Section III.A. hereof shall be subject to all of the terms and conditions of the
Plan, including, without limitation, the administrative provisions of the Plan
and the provisions of the Plan relating to the execution and delivery of a
Release as a condition to the receipt of severance benefits; provided, however,
that (a) the provisions of Section III of the Plan (relating to eligibility) and
Section IV.E. of the Plan (relating to rehired employees) shall not apply to the
First Supplemental Plan, (b) the amount of the cash severance payment to be
provided under the First Supplemental Plan shall be determined pursuant to
Section III.A.(a) hereof rather than Section IV.A. of the Plan, and (c) should
an inconsistency or conflict exist between the specific terms of the First
Supplemental Plan and those of the Plan, then the relevant terms of the First
Supplemental Plan shall govern and control.  Except as provided in Section
III.A.(b) hereof, a Participant shall not be required to mitigate the amount of
any payment or benefit provided for in Section III.A. hereof by seeking other
employment or otherwise, nor shall the amount of any payment or benefit provided
for in Section III.A. hereof be reduced by any compensation or benefit earned by
the Participant as the result of employment by another employer or by retirement
benefits.  The benefits under the First Supplemental Plan are in addition to any
other benefits to which a Participant is otherwise entitled, except that a
Participant who is entitled to receive a benefit under the First Supplemental
Plan shall not receive a benefit under the Plan, any other supplement thereto,
or any other severance benefit plan maintained by the Company or any of its
affiliates.

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IV.  AMENDMENT AND TERMINATION

     The First Supplemental Plan may be amended from time to time, or terminated
and discontinued, at any time, in each case at the discretion of Dynegy.
Notwithstanding the foregoing, the First Supplemental Plan may not be amended or
terminated within one year following a Change in Control.

     EXECUTED this ______ day of _____________________, 1999.

                                     DYNEGY INC.


                                     By:
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                                     Michael B. Barton
                                     Vice President of Human Resources

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