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                                                                   Exhibit 10(o)



                        CONSTELLATION ENERGY GROUP, INC.
                        --------------------------------


                       SENIOR EXECUTIVE SUPPLEMENTAL PLAN
                       ----------------------------------



                           Effective January 1, 2000
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                        CONSTELLATION ENERGY GROUP, INC.
                        --------------------------------


                       SENIOR EXECUTIVE SUPPLEMENTAL PLAN
                       ----------------------------------


1.   Objective.  The objective of this Plan is to enhance the benefits provided
     ---------
     to certain senior executives of Constellation Energy Group and its
     subsidiaries in order to attract and retain talented executive personnel.

2.   Definitions.  All words beginning with an initial capital letter and not
     -----------
     otherwise defined herein shall have the meaning set forth in the Pension
     Plan.   All singular terms defined in this Plan will include the plural and
     vice versa. As used herein, the following terms will have the meaning
     ----------
     specified below:

     "Average Annual Base Salary" means an amount determined by (a) computing
     the monthly base rate of pay amounts (i.e., the types of such pay that are
     includable in the computation of Pension Plan benefits) paid during the
     prior five consecutive twelve month periods immediately preceding the month
     that includes the date of the computation, and (b) averaging the two twelve
     month periods during which the highest amounts were paid.

     "Average Incentive Award" (or "Average Award") means the average of the two
     highest of the participant's five immediately prior year awards earned
     under Constellation Energy Group's Executive Annual Incentive Plan,
     Constellation Energy Group's Senior Management Annual Incentive Plan and/or
     Other Incentive Awards Programs.

     "Benefit Start Date" means the date as of which the participant's benefits,
     if any, under this Plan commence.

     "Cause" means the participant's (a) failure to comply with Constellation
     Energy Group policy, (b) deliberate and continual refusal to satisfactorily
     perform employment duties on substantially a full-time basis, (c)
     deliberate and continual refusal to act in accordance with any specific
     instructions of a majority of Constellation Energy Group's Board of
     Directors, (d) disclosure, without the consent of a majority of
     Constellation Energy Group's Board of Directors, of confidential
     information or trade secrets concerning Constellation Energy Group which
     could be materially damaging to Constellation Energy Group, or (e)
     deliberate
<PAGE>

     misconduct which could be materially damaging to Constellation Energy Group
     without reasonable good faith belief by the participant that such conduct
     was in the best interest of Constellation Energy Group.

     "Change in Control" means (a) the purchase or acquisition by any person,
     entity or group of persons, (within the meaning of Section 13(d) or 14(d)
     of the Securities Exchange Act of 1934 (the "Exchange Act"), or any
     comparable successor provisions), of beneficial ownership (within the
     meaning of Rule 13d-3 promulgated under the Exchange Act) of 20 percent or
     more of either the outstanding shares of common stock of Constellation
     Energy Group or the combined voting power of Constellation Energy Group's
     then outstanding shares of voting securities entitled to a vote generally,
     or (b) the consummation of, following the approval by the stockholders of
     Constellation Energy Group of a reorganization, merger, or consolidation of
     Constellation Energy Group, in each case, with respect to which persons who
     were stockholders of Constellation Energy Group immediately prior to such
     reorganization, merger or consolidation do not, immediately thereafter, own
     more than 50 percent of the combined voting power entitled to vote
     generally in the election of directors of the reorganized, merged or
     consolidated entity's then outstanding securities, or (c) a liquidation or
     dissolution of Constellation Energy Group or the sale of substantially all
     of its assets, or (d) a change of more than one-half of the members of the
     Board of Directors of Constellation Energy Group within a 90-day period for
     reasons other than the death, disability, or retirement of such members.

     "Committee" means the Committee on Management of the Board of Directors of
     Constellation Energy Group.

     "Constellation Energy Group" means Constellation Energy Group, Inc., a
     Maryland corporation, or its successor.

     "Constellation Energy Group's Executive Annual Incentive Plan" means such
     plan or other incentive plan or arrangement designated in writing by the
     Plan Administrator.

     "Constellation Energy Group's Senior Management Annual Incentive Plan"
     means such plan or other incentive plan or arrangement designated in
     writing by the Plan Administrator.

     "Demotion" means a transfer to a position with Constellation Energy Group
     or a subsidiary of Constellation Energy Group
<PAGE>

     that either (a) is substantially below the position in which the
     participant was employed on the date of transfer, or (b) results in a
     substantial reduction in pay when compared to the participant's pay on the
     date of the transfer. Whether a position is substantially below another
     position shall be determined in the reasonable discretion of the Committee,
     with reference to factors including whether the participant retains
     principal responsibility for a department or division, and whether the
     participant remains eligible for the perquisites enjoyed by the participant
     before the position change.

     "Early Receipt Reduction Factor" means 100% less 1/3 of 1% for each month
     that the participant is less than age 62 on the participant's Benefit Start
     Date.

     "Interest Rate" means the rate equal to the average monthly 30-year
     Treasury bond rate for the second calendar quarter preceding the
     computation date, less 50 basis points.

     "Internal Revenue Code Limitations" means the limitations under Section 415
     and/or 401(a)(17) of the Internal Revenue Code.

     "LTD Plan" means the Constellation Energy Group, Inc. Disability Insurance
     Plan as may be amended from time to time, or any successor plan.

     "Mortality Table" means the mortality table used to convert annuities to
     lump sums in the Pension Plan.

     "Other Incentive Awards Program" means the program(s) designated in writing
     by the Plan Administrator applicable to certain employees that provides
     awards; but includes only the types of awards that are includable in the
     computation of Pension Plan benefits.

     "Pension Plan" means the Pension Plan of Constellation Energy Group, Inc.
     as may be amended from time to time, or any successor plan.

     "Plan" means this Constellation Energy Group, Inc. Senior Executive
     Supplemental Plan.

     "Plan Administrator" means, as set forth in Section 3, the Committee.
<PAGE>

     "Rabbi Trust" means the trust adopted by Constellation Energy Group
     pursuant to the Grantor Trust Agreement Dated as of January 1, 2001,
     between Constellation Energy Group and Citibank, N.A.

     "Survivor Annuity Percentage" means 50%, unless the participant elects, in
     the timing and manner established by the Plan Administrator, a higher
     percentage (in multiples of 5% to a total percentage not to exceed 100%).

     "Termination From Employment With Constellation Energy Group" means a
     participant's separation from service with Constellation Energy Group or a
     subsidiary of Constellation Energy Group; however, a participant's
     retirement, disability, or transfer of employment to or from a subsidiary
     of Constellation Energy Group shall not constitute a Termination From
     Employment With Constellation Energy Group.

     "Total SERP Service" means (a) Credited Service accumulated while
     designated as a participant with respect to supplemental pension benefits
     under this Plan or while a participant under the Constellation Energy Group
     Supplemental Pension Plan, or while a participant under any predecessor
     executive supplemental pension benefit plan, plus (b) one fourth of
     Credited Service accumulated while not such a participant.

3.   Plan Administration.  The Committee is the Plan Administrator and has sole
     -------------------
     authority (except as specified otherwise herein) to interpret the Plan and,
     in general, to make all other determinations advisable for the
     administration of the Plan to achieve its stated objective.  Appeals of
     written decisions by the Plan Administrator may be made to the Board of
     Directors of Constellation Energy Group.  Decisions by the Board shall be
     final and not subject to further appeal.  The Plan Administrator shall have
     the power to delegate all or any part of its duties to one or more
     designees, and to withdraw such authority, by written designation.

4.   Eligibility.  Each senior executive of Constellation Energy Group or its
     -----------
     subsidiaries may be designated in writing by the Plan Administrator as a
     participant with respect to one or more benefits under the Plan. Once
     designated, participation shall continue until such designation is
     withdrawn at the discretion and by written order of the Plan Administrator,
     provided, however, that such withdrawal may
<PAGE>

     not be made with respect to a participant who has satisfied the eligibility
     requirements to retire (as set forth in Section 5(b)(i)). Notwithstanding
     the foregoing, any participant while classified as disabled under the LTD
     Plan shall continue to participate in this Plan while classified as
     disabled and, for purposes of the supplemental pension benefit provided by
     this Plan, while classified as disabled, shall be deemed to continue to
     accrue Credited Service until no later than his/her Normal Retirement Date.

5.   Supplemental Pension Benefit.
     -----------------------------

     (a) Generally.
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         (i) A Plan participant who was a participant in the Constellation
         Energy Group Supplemental Pension Plan on January 1, 2000, shall be
         eligible for supplemental pension benefits under this Plan only if the
         participant's supplemental pension benefits under this Plan are greater
         than the supplemental pension benefits computed under the Constellation
         Energy Group Supplemental Pension Plan based on the participant's age,
         service, and eligible compensation on the date as of which benefits
         become payable. If a participant or a participant's surviving spouse
         receives benefits from this Plan, he/she cannot also receive benefits
         from the Constellation Energy Group Supplemental Pension Plan.

         (ii) Any other participant in the Plan shall be eligible for benefits
         under this Plan without regard to any computation under the
         Constellation Energy Group Supplemental Pension Plan.

(b)  Retirement benefits.
     -------------------

         (i)  Eligibility for retirement benefits. A participant shall be
              -----------------------------------
              eligible to retire under this Plan on or after the participant's
              Normal Retirement Date, or on the first day of any month preceding
              his/her Normal Retirement Date, if on his/her Severance From
              Service Date and while a participant he/she has attained (1) age
              55 and has accumulated at least 10 years of Credited Service; or
              (2) age 62 and has accumulated at least five years of Credited
              Service.

         (ii) Computation of retirement benefits.  A participant who is
              ----------------------------------
              eligible to retire under this Plan will be
<PAGE>

               entitled to supplemental pension retirement benefits under this
               Plan, which will be calculated as set forth below on the
               participant's Benefit Start Date:

               (1)  add the Average Annual Base Salary and the Average Incentive
                    Award,

               (2)  divide the sum by 12,

               (3)  multiply this dollar amount by the appropriate percentage,
                    determined as follows: Chairman of the Board of
                    Constellation Energy Group - 60%; all other participants
                    (the product of 5.5% multiplied by the number of full and
                    fractional years of Total SERP Service), (maximum is 55%).

               (4)  multiply this dollar amount by the Early Receipt Reduction
                    Factor; provided, however, if the participant is age 62 or
                    older on his/her Benefit Start Date, such factor shall be
                    one (1),

               (5)  subtract from this dollar amount the charges relating to
                    coverage for a pre-retirement survivor annuity in excess of
                    50%, and for a post-retirement survivor annuity in excess of
                    50%, and

               (6)  subtract from the remainder the net monthly amount payable
                    to the participant under the Pension Plan on the
                    participant's Benefit Start Date (assuming a 50% spousal
                    joint and survivor annuity for a married participant), (if
                    the participant is not eligible to commence monthly Pension
                    Plan payments on the participant's Benefit Start Date, the
                    participant's benefit will be unreduced for Pension Plan
                    payments until the date the participant is first eligible to
                    commence monthly Pension Plan payments) , or, if the
                    participant elects a lump sum under the PEP provisions of
                    the Pension Plan, the monthly amount that would have been
                    payable under the Pension Plan as a life annuity for a
                    single participant or as a 50% spousal joint and
<PAGE>

                    survivor annuity for a married participant, as of the
                    Benefit Start Date under this Plan.

         (iii) Form of payout of retirement benefits.  Each participant entitled
               -------------------------------------
               to supplemental pension retirement benefits will receive his/her
               supplemental pension retirement benefits payout in the form of a
               monthly payment, unless the participant makes a valid election to
               receive his/her supplemental pension retirement benefits payout
               in the form of a lump sum.

               A participant may elect to receive his/her supplemental pension
               retirement benefits payout in the form of a lump sum by
               submitting to the Plan Administrator a signed Lump Sum Election
               Form.  The Form must be received by the Plan Administrator before
               the beginning of the calendar year during which the participant's
               Severance From Service Date occurs.  The election may be revoked
               at any time before the beginning of the calendar year during
               which the participant's Severance From Service Date occurs, by
               submitting to the Plan Administrator a signed Lump Sum Revocation
               Form.

         (iv)  Amount, timing, and source of monthly retirement benefit payout.
               ---------------------------------------------------------------
               A participant entitled to monthly supplemental pension retirement
               benefits will receive monthly payments equal to the amount
               determined under paragraph (b)(ii).  Such payments shall commence
               effective with the first of the month following the Participant's
               Severance From Service Date.  If such participant receives (or
               would have received but for the Internal Revenue Code
               Limitations) cost of living adjustment(s) under the Pension Plan,
               the monthly payments hereunder will be automatically increased
               based on the percentage of, and at the same time as, such
               adjustment(s).  Monthly payments hereunder shall permanently
               cease upon the death of the participant, effective with the
               monthly payment for the month following the month of the
               participant's death.  Monthly payments hereunder shall be made in
               accordance with the provisions of the Rabbi Trust and, to the
               extent not paid under the terms of the Rabbi Trust, from general
               corporate assets.
<PAGE>

          (v)  Amount, timing, and source of lump sum retirement benefit payout.
               ----------------------------------------------------------------
               A participant entitled to a lump sum supplemental pension
               retirement benefit will receive a lump sum payment.  This lump
               sum payment will be calculated by a certified actuary and will be
               equal to the present value of an immediate annuity including the
               estimated present value of post-retirement supplemental survivor
               annuity benefits described in Section 6, and reflecting the
               present value of any deferred Pension Plan payments using (1) the
               supplemental pension retirement benefit amount calculated under
               paragraph (b)(ii), which is expressed as a monthly amount, (2)
               the Interest Rate computed on the participant's Benefit Start
               Date, and (3) the Mortality Table.  Such lump sum payment shall
               be made within 60 days after the participant's Severance From
               Service Date.  The lump sum payment shall be made in accordance
               with the provisions of the Rabbi Trust and, to the extent not
               paid under the terms of the Rabbi Trust, from general corporate
               assets.  A participant who receives a lump sum payment shall not
               be entitled to any cost of living or other pension payment
               adjustments or to post-retirement survivor annuity coverage under
               the Plan.

          (vi) Death of participant entitled to lump sum payout.  In the event
               ------------------------------------------------
               of the death of a participant after his/her Severance From
               Service Date and before the participant receives the lump sum
               payment under paragraph (b)(v), such lump sum payment shall be
               made to the participant's surviving spouse (as defined in Section
               6(i)).  The lump sum payment shall be the same amount and made at
               the same time and from the same sources as set forth in paragraph
               (b)(v).  If there is no surviving spouse at the date of the
               participant's death, no payments shall be made pursuant to
               Sections 5 or 6.  A surviving spouse who receives a lump sum
               benefit under this paragraph (b)(vi) shall not be entitled to any
               cost of living or other pension payment adjustments or to post-
               retirement survivor annuity coverage under the Plan.

      (c) Entitlement to benefit upon happening of certain events.
          -------------------------------------------------------
<PAGE>

         (i)   Computation of gross accrued benefit.  The computation of the
               ------------------------------------
               gross accrued supplemental pension benefit for a participant as
               of the date of the computation will be made as follows:

               (1)  add the Average Annual Base Salary and the Average Incentive
                    Award,

               (2)  divide the sum by 12, and

               (3)  multiply this dollar amount by the appropriate percentage,
                    determined as follows: Chairman of the Board and President
                    of Constellation Energy Group - 60%; all other participants
                    (by the product of 5.5% multiplied by the number of full and
                    fractional years of Total SERP Service as of the date of the
                    computation) (maximum is 55%).

         (ii)  Computation of net accrued benefit.  The computation of the net
               ----------------------------------
               accrued supplemental pension benefit for a participant as of the
               date of the computation will be made by subtracting from the
               gross accrued benefit determined under paragraph (c)(i) the
               amount of the participant's Gross Pension under the Pension Plan
               determined as of the date of the computation and assuming that
               monthly payments of such Gross Pension begin on the first of the
               month after the later of reaching age 62 or the date of the
               computation.  If the participant is not eligible for payment of a
               Gross Pension under the Pension Plan, the participant's Accrued
               Gross Pension determined as of the date of the computation shall
               be substituted for the Gross Pension described above, with the
               appropriate reduction for early receipt applied as if the
               participant were eligible to begin payment of his Accrued Gross
               Pension on the first of the month after the later of reaching age
               62 or the date of the computation.

         (iii) Satisfaction of requirements.  A participant who has satisfied
               ----------------------------
               the age and Credited Service requirements set forth in Section
               5(b)(i) while eligible as set forth in Section 4, but who does
               not retire under the Plan due to Demotion,
<PAGE>

               Termination From Employment With Constellation Energy Group, or
               the withdrawal of a participant's eligibility to participate
               under Section 5, shall be entitled to his/her net accrued
               supplemental pension benefit. The effective date of the Demotion,
               Termination From Employment With Constellation Energy Group, or
               eligibility withdrawal event shall be the date of such Demotion,
               Termination From Employment With Constellation Energy Group, or
               eligibility withdrawal.

          (iv) Other events.  A participant, regardless of his/her age and years
               ------------
               of Credited Service, shall be entitled to his/her net accrued
               supplemental pension benefit upon the happening of any of the
               following entitlement events, but only if such entitlement event
               occurs while a participant and before a participant retires under
               this Plan:

               (1)  Change in Control.  A Change in Control, followed within two
                    -----------------
                    years by the participant's Demotion, a participant's
                    Termination From Employment With Constellation Energy Group,
                    or the withdrawal of the participant's eligibility to
                    participate under the Plan, is an entitlement event.  The
                    effective date of the entitlement event shall be the date of
                    the Demotion, Termination From Employment With Constellation
                    Energy Group, or eligibility withdrawal.

               (2)  Plan amendment.  A Plan amendment that has the effect of
                    --------------
                    reducing a participant's gross accrued supplemental pension
                    benefit is an entitlement event.  In determining whether
                    such a reduction has occurred, the participant's gross
                    accrued supplemental pension benefit calculated on the day
                    immediately preceding the effective date of the amendment
                    shall be compared to the participant's gross accrued
                    supplemental pension benefit calculated on the effective
                    date of the amendment.  An amendment that has the effect of
                    reducing future benefit accruals is not an entitlement
                    event.  It is intended that an entitlement event under this
<PAGE>

                    paragraph (c)(iii)(2) will occur only with respect to those
                    amendments that are substantially similar to amendments that
                    are prohibited by Internal Revenue Code section 411(d)(6)
                    with respect to qualified pension plans.  The effective date
                    of the entitlement event shall be the effective date of the
                    Plan amendment.

               (3)  Involuntary Demotion, Termination From Employment With
                    ------------------------------------------------------
                    Constellation Energy Group, or eligibility withdrawal
                    -----------------------------------------------------
                    without Cause.  A participant's involuntary Demotion or
                    -------------
                    involuntary Termination From Employment With Constellation
                    Energy Group without Cause, or the withdrawal of a
                    participant's eligibility to participate under Sections 5 or
                    6 of the Plan without Cause, is an entitlement event.  The
                    effective date of the entitlement event shall be the
                    effective date of the participant's involuntary Demotion or
                    involuntary Termination From Employment With Constellation
                    Energy Group without Cause, or the eligibility withdrawal
                    without Cause.

          (v)  Form of benefit payout. Each participant entitled to a payout
               ----------------------
               under this paragraph (c) will receive such payout in the form of
               a lump sum payment.

          (vi) Amount, timing, and source of benefit payout.  A participant
               --------------------------------------------
               entitled to a payout of his/her net accrued benefit, as a result
               of the occurrence of an event described in paragraphs (c)(iii),
               (c)(iv)(1), (2), or (3) will be entitled to a lump sum benefit.
               This lump sum benefit will be calculated by a certified actuary
               as the present value, determined as of the date of payment, of an
               annuity beginning at age 62 (or the participant's actual age, if
               the participant is older than age 62 on the date the lump sum
               benefit is payable), including the estimated present value of
               post-retirement survivor annuity benefits described in Section 6,
               using (1) the net accrued benefit amount calculated under
               paragraph (d)(iv) on the effective date of the entitlement event,
               which is expressed as a monthly amount, (2) the Interest Rate
               computed on the date the lump sum benefit is
<PAGE>

               payable, and (3) the Mortality Table. The lump sum benefit shall
               be payable as of of the participant's Severance From Service
               Date, and shall be made within 60 days after such date in
               accordance with the provisions of the Rabbi Trust and, to the
               extent not paid under the terms of the Rabbi Trust, from general
               corporate assets. A participant who receives a lump sum benefit
               under this paragraph (c)(vi) shall not be entitled to any cost of
               living or other pension payment adjustments or to pre-retirement
               or post-retirement survivor annuity coverage.

         (vii) Death of participant entitled to lump sum payout.  In the event
               ------------------------------------------------
               of the death of a participant after the occurrence of an event
               described in paragraphs (c)(iii), (c)(iv)(1), (2), or (3) and
               before the participant receives the lump sum payment under
               paragraph (c)(vi), a lump sum payment shall be made to the
               participant's surviving spouse (as defined in Section 6(i)).  The
               lump sum payment will be calculated by a certified actuary and
               will be equal to 100% of the lump sum that would have been paid
               to the participant under paragraph (vi), as of the date on which
               the lump sum is payable under this paragraph (vii), provided that
               the participant's date of death is on or after his/her Severance
               From Service Date.  If the participant's date of death is before
               his/her Severance From Service Date, 50% shall be substituted for
               100% in the preceding sentence.  The lump sum benefit shall be
               payable as of the earlier of the participant's Severance From
               Service Date or date of death, and shall be made within 60 days
               after such date in accordance with the provisions of the Rabbi
               Trust and, to the extent not paid under the terms of the Rabbi
               Trust, from general corporate assets.  If there is no surviving
               spouse at the date of the participant's death, no payments shall
               be made pursuant to Sections 5 or 6.  A surviving spouse who
               receives a lump sum benefit under this paragraph (c) (vii) shall
               not be entitled to any cost of living or other pension payment
               adjustments or to pre-retirement or post-retirement survivor
               annuity coverage under the Plan.
<PAGE>

6.   Supplemental Survivor Annuity Benefit.
     -------------------------------------

     (a)  Survivor annuity benefit.
          ------------------------

          (i)  Eligibility for survivor annuity benefit.  Following the death of
               ----------------------------------------
               a participant who is fully vested under the Pension Plan, a
               supplemental survivor annuity may be paid to the participant's
               surviving spouse until the death of that spouse, using the
               Survivor Annuity Percentage. The participant will not bear the
               cost of up to a 50% survivor annuity benefit, but will bear the
               cost of a survivor annuity benefit in excess of 50%.  For
               purposes of this Section 6(a), a participant's surviving spouse
               is the individual married to the participant on the date of the
               participant's death.  If there is no surviving spouse, or if the
               participant or the participant's spouse previously received or is
               entitled to receive a lump sum payment under Section 5, no
               supplemental survivor annuity will be payable.

          (ii) Computation of survivor annuity benefit.  The amount of the
               ---------------------------------------
               supplemental survivor annuity will be determined as follows:

               (1)  if the participant's Benefit Start Date occurred prior to
                    the date of death:

                    (a)  begin with the monthly pension benefit (under Section
                         5(b) of this Plan) that the participant was receiving
                         prior to the date of death, and

                    (b)  multiply this dollar amount by the Survivor Annuity
                         Percentage.

               (2)  otherwise:

                    (a)  Unless the participant elected the alternative in-
                         service death benefit in section (b) below:

                         (1) begin with the  monthly Early Retirement pension
                         benefit (under both the Pension Plan and Section 5(b)
                         of this Plan) to which the participant
<PAGE>

                         would have been entitled if the participant had been
                         retired at the later of age 60 or his/her actual age on
                         the date of death for purposes of computing the Early
                         Receipt Reduction Factor,

                         (2) multiply this dollar amount by the Survivor Annuity
                         Percentage,

                         (3) subtract from the product the net amount, if any,
                         of the survivor annuity provided on behalf of the
                         participant under the Pension Plan if the participant
                         is participating in the Traditional Pension Plan, or
                         the monthly annuity that would have been provided to
                         the participant's spouse assuming that he or she had
                         been designated as the participant's beneficiary and
                         had chosen to receive a survivor benefit in the form of
                         a monthly annuity, if the participant is participating
                         in the PEP, and

                         (4) subtract from this dollar amount the charges
                         relating to coverage (under both the Pension Plan and
                         this Plan) for a pre-retirement survivor annuity in
                         excess of 50%.

                   (b)   If the participant was a participant in the Pension
                         Equity Plan option of the Pension Plan and elected this
                         alternative in-service death benefit by December 31 of
                         the year prior to his/her death or during the 2001
                         initial election period established by the Plan
                         Administrator

                         (1)  calculate the benefit under the Constellation
                              Energy Group Benefits Restoration Plan that would
                              have been payable to the surviving spouse if the
                              participant were a participant in that plan and
<PAGE>

                         (2)  that dollar amount will be paid to the surviving
                              spouse only in the form of a lump sum from this
                              Plan.

         (iii) Form of payout of survivor annuity benefits. Unless the
               -------------------------------------------
               participant made a valid election by December 31 of the year
               prior to his/her death or during the 2001 initial election period
               established by the Plan Administrator, to have the survivor
               benefits paid in a lump sum, each surviving spouse entitled to a
               supplemental survivor annuity benefit will receive his/her
               survivor annuity benefit payout in the form of a monthly payment.

         (iv)  Amount, timing, and source of monthly survivor annuity benefit
               --------------------------------------------------------------
               payout.  A surviving spouse entitled to monthly supplemental
               ------
               survivor annuity benefits will receive a monthly payment equal to
               the amount determined under (ii) above.  Such payments shall
               commence effective with the first day of the month following the
               month of the participant's death.  If such surviving spouse
               receives (or would have received but for the Internal Revenue
               Code Limitations) cost of living adjustment(s) under the Pension
               Plan, the monthly payments hereunder will be automatically
               increased based on the percentage of, and at the same time as,
               such adjustment(s).  Monthly payments hereunder shall permanently
               cease upon the death of the surviving spouse, effective with the
               monthly payment for the month following the month of the
               surviving spouse's death.  Monthly payments hereunder shall be
               made in accordance with the provisions of the Rabbi Trust and, to
               the extent not paid under the terms of the Rabbi Trust, from
               general corporate assets.

         (v)   Amount, timing, and source of lump sum survivor benefit payout. A
               --------------------------------------------------------------
               surviving spouse entitled to lump sum supplemental survivor
               benefit will receive a lump sum payment.  This lump sum payment
               will be calculated by a certified actuary and will be equal to
               the present value of an immediate annuity. Such lump sum payment
               shall be made within 60 days after the participant's death.  The
               lump sum payment shall be made in accordance with
<PAGE>

               the provisions of the Rabbi Trust and, to the extent not paid
               under the terms of the Rabbi Trust, from general corporate
               assets. A surviving spouse who receives a lump sum payment shall
               not be entitled to any cost of living or other pension payment
               adjustments.

          (vi) Death of surviving spouse entitled to lump sum payout.  In the
               -----------------------------------------------------
               event of the death of a surviving spouse before the spouse
               receives the lump sum payment under section 6(a)(v) no payment
               shall be made.

7.   Death Benefit. Constellation Energy Group shall make arrangements, through
     -------------
     its split-dollar life insurance program or otherwise, for life insurance
     coverage for each designated participant providing that the participant's
     beneficiary shall receive, as a pre-retirement (or pre-rollout benefit for
     participants as of 4/1/2000) death benefit, an amount which is
     approximately equal to three times the participant's base salary control
     point plus target annual incentive (as determined in the sole discretion of
     the Plan Administrator), and as a post-retirement death benefit(or post-
     rollout benefit for participants as of 4/1/2000), an amount which is
     approximately equal to two times the participant's base salary control
     point plus target annual incentive (as determined in the sole discretion of
     the Plan Administrator), as set forth in a separate agreement between the
     participant and his/her employer.

     As determined in the sole discretion of the Plan Administrator, in the
     event that either (i) a participant is ineligible to receive the type of
     life insurance coverage provided to other participants under this Plan, or
     (ii) such coverage is not available on reasonably cost-effective terms as a
     result of any penalty for smoking or other factors that are reflected in
     the insurance carrier's rates, then Constellation Energy Group shall
     provide a benefit that, in the discretion of the Plan Administrator, is
     substantially equivalent to the cost of the benefit provided to other
     participants under this Plan.

8.   Dependent Death Benefit.  For a participant with a split-dollar policy
     -----------------------
     under Section 7, in the event of the death of a participant's qualified
     dependent while the participant is an active employee of Constellation
     Energy Group or a
<PAGE>

     subsidiary of Constellation Energy Group, Constellation Energy Group shall
     make a death benefit payment to the participant, from general corporate
     assets. For purposes of this Section 8, qualified dependent shall have the
     same meaning as set forth in Constellation Energy Group's Family Life
     Insurance Plan. For purposes of this Section 8, the amount of death benefit
     payment shall be the highest amount of insurance that would have been
     payable with respect to such qualified dependent if coverage had been
     provided under Constellation Energy Group's Family Life Insurance Plan. The
     dependent death benefit payment under this Plan shall be grossed-up for
     income tax withholding.

9.   Miscellaneous.  None of the benefits provided under this Plan shall be
     -------------
     subject to alienation or assignment by any participant or beneficiary nor
     shall any of them be subject to attachment or garnishment or other legal
     process except (i) to the extent specially mandated and directed by
     applicable State or Federal statute; (ii) as requested by the participant
     or beneficiary to satisfy income tax withholding or liability; and (iii)
     any policy of insurance written by a commercial carrier on a split-dollar
     basis shall be assignable.

     This Plan may be amended from time to time, or suspended or terminated at
     any time, provided, however, that no amendment or termination shall reduce
     any previously accrued supplemental pension benefit under this Plan or
     impair the rights of any participant or beneficiary entitled to receive
     current or future payment hereunder at the time of such action.  All
     amendments to this Plan which would increase or decrease the compensation
     of any Officer of Constellation Energy Group, either directly or
     indirectly, must be approved by the Board of Directors.  All other
     permissible amendments may be made at the written direction of the
     Committee. Notwithstanding anything else in this Plan to the contrary, the
     Constellation Energy Group Board of Directors may authorize a Participant
     to be eligible for benefits or may increase benefit payments.

     Participation in this Plan shall not constitute a contract of employment
     between Constellation Energy Group and any person and shall not be deemed
     to be consideration for, or a condition of, continued employment of any
     person.

     The Plan, notwithstanding the creation of the Rabbi Trust, is intended to
     be unfunded for purposes of Title I of the Employee Retirement Income
     Security Act of 1974.
<PAGE>

     Constellation Energy Group shall make contributions to the Rabbi Trust in
     accordance with the terms of the Rabbi Trust. Any funds which may be
     invested and any assets which may be held to provide benefits under this
     Plan shall continue for all purposes to be a part of the general funds and
     assets of Constellation Energy Group and no person other than Constellation
     Energy Group shall by virtue of the provisions of this Plan have any
     interest in such funds and assets. To the extent that any person acquires a
     right to receive payments from Constellation Energy Group under this Plan,
     such rights shall be no greater than the right of any unsecured general
     creditor of Constellation Energy Group.

     In the event Constellation Energy Group becomes a party to a merger,
     consolidation, sale of substantially all of its assets or any other
     corporate reorganization in which Constellation Energy Group will not be
     the surviving corporation or in which the holders of the common stock of
     Constellation Energy Group will receive securities of another corporation
     (in any such case, the "New Company"), then the New Company shall assume
     the rights and obligations of Constellation Energy Group under this Plan.

     This Plan shall be governed in all respects by Maryland law.