AMENDED AND RESTATED AMEREN CORPORATION CHANGE OF CONTROL SEVERANCE PLAN

(a)    Annual Bonus Award . The target annual cash bonus that a Participant is eligible to earn for the year in which a Change in Control occurs pursuant to the Company’s Executive Incentive Plan, the Ameren Corporation 2006 Omnibus Incentive Compensation Plan, or any successor to either such plan.

(b)    Annual Salary . The Participant’s regular annual base salary immediately prior to his or her termination of employment, including compensation converted to other benefits under a flexible pay arrangement maintained by any Employer or deferred pursuant to a written plan or agreement with any Employer.

(c)    Board . The Board of Directors of the Company.

(d)    Cause . The occurrence of any one or more of the following:

(i)    The Participant’s willful failure to substantially perform his duties with the Company (other than any such failure resulting from the Participant’s Disability), after a written demand for substantial performance is delivered to the Participant that specifically identifies the manner in which the Committee believes that the Participant has not substantially performed his duties, and the Participant has failed to remedy the situation within fifteen (15) business days of such written notice from the Company;

(ii)    Gross negligence in the performance of the Participant’s duties which results in material financial harm to the Company;

(iii)    The Participant’s conviction of, or plea of guilty or nolo contendere , to any felony or any other crime involving the personal enrichment of the Participant at the expense of the Company or shareholders of the Company; or

(iv)    The Participant’s willful engagement in conduct that is demonstrably and materially injurious to the Company, monetarily or otherwise.

(e)    Change of Control . The occurrence of any of the following events after the Effective Date of this Plan:

(i)    The acquisition by any individual, entity or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) (a “Person”) of beneficial ownership (within the meaning of Rule 13d-3 promulgated under the Exchange Act) of 20% or more of either (x) the then outstanding shares of common stock of the Company (the “Outstanding Company Common Stock”) or (y) the combined voting power of the then outstanding voting securities of the Company entitled to vote generally in the election of directors (the “Outstanding Company Voting Securities”); provided, however, that for purposes of this subsection (i), the following acquisitions shall not constitute a Change of Control: (A) any acquisition directly from the Company, (B) any acquisition by the Company, (C) any acquisition by any employee benefit plan (or related trust) sponsored or maintained by the Company or any corporation controlled by the Company or (D) any acquisition by any corporation pursuant to a transaction which complies with clauses (A), (B) and (C) of paragraph (iii) below; or

(ii)    Individuals who, as of the Effective Date of this Plan, constitute the Board (the “Incumbent Board”) cease for any reason to constitute at least a majority of the Board; provided, however, that any individual becoming a director subsequent to the Effective Date whose election, or nomination for election by the Company’s shareholders, was approved by a vote of at least a majority of the directors then comprising the Incumbent

Board shall be considered as though such individual were a member of the Incumbent Board, but excluding, for this purpose, any such individual whose initial assumption of office occurs as a result of (A) an actual or threatened election contest with respect to the election or removal of directors or other actual or threatened solicitation of proxies or consents by or on behalf of a Person other than the Board or (B) any agreement intended to avoid or settle any election contest; or

(iii)    Consummation of a reorganization, merger or consolidation or sale or other disposition of all or substantially all of the assets of the Company or the acquisition of assets of another corporation (a “Business Combination”), in each case, unless, following such Business Combination, (A) all or substantially all of the individuals and entities who were the beneficial owners, respectively, of the Outstanding Company Common Stock and Outstanding Company Voting Securities immediately prior to such Business Combination beneficially own, directly or indirectly, more than 60% of, respectively, the then outstanding shares of common stock and the combined voting power of the then outstanding voting securities entitled to vote generally in the election of directors, as the case may be, of the corporation resulting from such Business Combination (including, without limitation, a corporation which as a result of such transaction owns the Company or all or substantially all of the Company’s assets either directly or through one or more subsidiaries) in substantially the same proportions as their ownership, immediately prior to such Business Combination of the Outstanding Company Common Stock and Outstanding Company Voting Securities, as the case may be, (B) no Person (excluding any corporation resulting from such Business Combination or any employee benefit plan (or related trust) of the Company or such corporation resulting from such Business Combination) beneficially owns, directly or indirectly, 20% or more of, respectively, the then outstanding shares of common stock of the corporation resulting from such Business Combination or the combined voting power of the then outstanding voting securities of such corporation except to the extent that such ownership existed prior to the Business Combination and (C) at least a majority of the members of the board of directors of the corporation resulting from such Business Combination were members of the Incumbent Board at the time of the execution of the initial agreement, or of the action of the Board, providing for such Business Combination; or

(iv)    Approval by the shareholders of the Company of a complete liquidation or dissolution of the Company.

Notwithstanding the foregoing, a Change of Control shall not be deemed to occur solely because any Person (the “Subject Person”) acquired beneficial ownership of more than the permitted amount of the then Outstanding Company Common Stock or the Outstanding Company Voting Securities as a result of the acquisition of shares of common stock or voting securities by the Company which, by reducing the number of shares of Outstanding Company Common Stock or the Outstanding Company Voting Securities, increases the proportional number of shares beneficially owned by the Subject Persons, provided that if a Change of Control would occur (but for the operation of this sentence) as a result of the acquisition of shares of Outstanding Company Common Stock or the Outstanding Company Voting Securities by the Company, and after such share acquisition by the Company, the Subject Person becomes the beneficial owner of any additional shares of Outstanding Company Common Stock or the Outstanding Company Voting Securities which increases the percentage of the then Outstanding Company Common Stock or the

Outstanding Company Voting Securities beneficially owned by the Subject Person, then a Change of Control shall occur.

(f)    Code . The Internal Revenue Code of 1986, as amended from time to time.

(g)    Committee . The Human Resources Committee of the Board.

(h)    Company . Ameren Corporation and any successors thereto.

(i)    Date of the Change of Control . The date on which a Change of Control occurs.

(j)    Date of Termination . The date on which a Participant ceases to be an Employee.

(k)    Disability . A termination of a Participant’s Employment for Disability shall have occurred if the Termination occurs because of a disability which qualifies the Participant for benefits under the Company’s long-term disability plan.

(l)    Effective Date . February 10, 2006

(m)    Employee . Any full-time, regular-benefit, non-bargaining employee of the Company or any other Employer.

(n)    Employer . The Company or any subsidiary of the Company.

(o)    Employment . The state of being an Employee.

(p)    ERISA . The Employee Retirement Income Security Act of 1974, as amended, and the regulations thereunder.

(q)    Good Reason . The occurrence after a Change in Control of the Company of any one or more of the following without the Participant’s express written consent:

(i)    A net reduction of the Participant’s authorities, duties, or responsibilities as an executive and/or officer of the Company from those in effect prior to the Change in Control, other than an insubstantial and inadvertent reduction that is remedied by the Company promptly after receipt of notice thereof given by the Participant;

(ii)    The Company’s requiring the Participant to be based at a location in excess of fifty (50) miles from the location of the Participant’s principal job location or office immediately prior to the Change of Control; except for required travel on the Company’s business to an extent substantially consistent with the Participant’s then present business travel obligations;

(iii)    Any material reduction by the Company of the Participant’s Base Salary or targeted Annual Bonus Awards, in effect on the Date of the Change of Control, or as the same shall be increased from time to time;

(iv)    The failure to provide the Participant with an annualized long-term incentive opportunity which is either essentially equivalent in value to or greater in value than the Participant’s regular annualized long-term incentive opportunity in effect on the Date of the Change of Control (for this purpose, the permissible floor value is intended to reference normal long-term incentive awards made as a part of the regular annual pay package, and not special awards that are not made on a regular basis) when calculated on a grant date basis using widely recognized valuation methodologies (e.g., Black-Scholes for options);

(v)    The failure of the Company to continue in effect the aggregate value in any of the employee benefit or retirement plans in which the Participant participates prior to the Change in Control of the Company;

(vi)    The failure of the Company to obtain a satisfactory agreement from any successor to the Company to assume and agree to perform the Company’s obligations under this Plan, as contemplated in Article V herein; and

(vii)    A material breach of this Plan by the Company which is not remedied by the Company within ten (10) business days of receipt of written notice of such breach delivered by the Participant to the Company.

In the event it is necessary to determine the value of a long-term incentive opportunity under Section q(iv) above or the aggregate value of employee benefit or retirement plans under Section q(v) above, an outside independent benefit consulting firm shall be engaged by the Company to make such determination.

(r)    Multiple . With respect to any Participant, the number set forth opposite the Participant’s name under the heading “Benefit Level” on Schedule I hereto.  

(s)    Participant . An individual who is designated as such pursuant to Section 3.1.

(t)    Plan . The Ameren Corporation Change of Control Severance Plan.

(u)    Retirement . A termination by Retirement shall have occurred where a Participant’s termination is due to his or her late, normal or early retirement under a pension plan sponsored by the Company or any of its affiliates, as defined in such plan.

(v)    Separation Benefits . The benefits described in Section 4.2 that are provided to qualifying Participants under the Plan.

(w)    Separation Period . With respect to any Participant, the period beginning on a Participant’s Date of Termination and ending after the expiration of a number of years equal to the Multiple for such Participant.

3.1    Participants . Each of the individuals named on Schedule I hereto shall be a Participant in the Plan.

3.2    Duration of Participation . A Participant shall only cease to be a Participant in the Plan as a result of an amendment or termination of the Plan complying with Article VI of the Plan, or when he ceases to be an Employee, unless, at the time he ceases to be an Employee, such Participant is entitled to payment of a Separation Benefit as provided in the Plan or there has been an event or occurrence that constitutes Good Reason which would enable the Participant to terminate his employment and receive a Separation Benefit. A Participant entitled to payment of a Separation Benefit or any other amounts under the Plan shall remain a Participant in the Plan until the full amount of the Separation Benefit and any other amounts payable under the Plan have been paid to the Participant.

4.1    Terminations of Employment Which Give Rise to Separation Benefits Under Plan . A Participant shall be entitled to Separation Benefits as set forth in Section 4.2 below if, at any time before the second anniversary of the Date of the Change of Control, the Participant’s Employment is terminated (i) by the Employer for any reason other than Cause or (ii) by the Participant within 90 days after the occurrence of Good Reason. A Participant shall not be entitled to Separation Benefits if the Participant’s Employment is terminated (i) voluntarily by the Participant without Good Reason (or more than 90 days after any event which constitutes the occurrence of Good Reason) or (ii) by reason of death or Disability or (iii) by the Employer for Cause. In addition, if a Participant’s employment is terminated by the Company without Cause prior to the date of a Change of Control, either (i) at the request of a third party who has indicated an intention or taken steps reasonably calculated to effect such Change of Control, or (ii) otherwise in connection with, or in anticipation of, such a Change of Control which has been threatened or proposed, such termination shall be deemed to have occurred after a Change of Control for purposes of this Plan provided a Change of Control shall actually occur.

4.2    Separation Benefits .

(a)    If a Participant’s employment is terminated under circumstances entitling him to Separation Benefits as provided in Section 4.1, the Company shall pay such Participant, within 30 days of the Date of Termination, a cash lump sum as set forth in subsection (b) below and the continued benefits set forth in subsection (c) below. For purposes of determining the benefits set forth in subsections (b) and (c), if the termination of the Participant’s employment is for Good Reason after there has been a reduction of the Participant’s Annual Salary, opportunity to earn Annual Bonuses, or other compensation or employee benefits, such reduction shall be ignored.

(b)    The cash lump sum referred to in Section 4.2(a) is the aggregate of the following amounts:

(i)    the sum of (1) the Participant’s Annual Salary through the Date of Termination to the extent not theretofore paid, (2) the product of (x) the Annual Bonus Award and (y) a fraction, the numerator of which is the number of days in such year through the Date of Termination, and the denominator of which is 365, and (3) any accrued vacation pay, to the extent not theretofore paid and in full satisfaction of the rights of the Participant thereto;