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EXHIBIT 10.31

Union Carbide Corporation Executives' Supplemental Retirement Plan

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Effective as of March 1, 2004
(except as may be otherwise provided herein)

PREAMBLES

ESTABLISHMENT OF PLAN

The Union Carbide Corporation maintained a non-qualified pension plan program
comprising of the Equalization Benefit Plan, the Supplemental Retirement Income
Plan and the Enhanced Retirement Income Plan. As of March 1, 2004, this program
and the aforementioned plans are amended and restated in their entirety as set
forth herein and renamed the Union Carbide Corporation Executives' Supplemental
Retirement Plan (the "Plan"). This is an unfunded program of deferred
compensation for executives, which includes Part A for Non-U.S. Service,
Non-Controlled Group Service and/or Non-Covered Controlled Group Service and
Part B for a Select Group of Management or Highly Compensated Employees, Board
Members, and Employees whose Benefits are Statutorily Limited. The terms of this
Plan supersede the terms of the former Union Carbide non-qualified pension plan
program in effect prior to the effective date of this Plan with regards to
active Participants and Participants who terminated employment prior to the
effective date but have not commenced benefits prior to the effective date.

PURPOSE

The Company desires (a) to provide certain of its executives and a select group
of management employees with supplemental retirement benefits that might
otherwise be provided by the Union Carbide Employees' Pension Plan ("UCEPP"),
but for (i) restrictions of the exclusive benefit rule under Section 401(a) of
the Internal Revenue Code (the "Code"), (ii) the inability to grant past
service, under UCEPP, to highly compensated Employees without meeting the
non-discrimination requirements of Section 401(a)(4) of the Code, and/or
(iii) the inability to credit service to Employees while employed by a
controlled group member not covered by the UCEPP, and (b) to restore benefits
which are reduced under UCEPP and The Dow Chemical Company Employees' Savings
Plan ("ESP") due to current and/or future statutory limitations and which are
not otherwise provided by any other plan maintained by the Company.

INTERPRETATION AND GOVERNING LAW

This Plan is intended to constitute an unfunded program maintained primarily for
the purpose of providing deferred compensation for a select group of management
or highly compensated Employees consistent with the requirements of Sections
201(2), 301(a)(3) and 401(a)(1) of the Employee Retirement Income Security Act
of 1974, as amended ("ERISA"). In the event ERISA does not preempt state law,
the state law of Michigan applies.

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PART A

FOR NON-U.S. SERVICE,
NON-CONTROLLED GROUP SERVICE,
AND/OR NON-COVERED CONTROLLED
GROUP SERVICE

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ARTICLE I
DEFINITIONS

1.01BENEFICIARY shall mean that person or persons designated by the Participant
to receive a distribution of any amounts payable under this Plan due to the
death of the Participant. The beneficiary of a Participant shall be deemed to be
such Participant's spouse, if married, or their domestic partner, if in a
domestic partner relationship as approved by the Company, unless such spouse
agrees in writing to waive this right (such waiver does not apply to a domestic
partner). If the Participant is not married or in an approved domestic partner
relationship and fails to designate a Beneficiary, the amounts payable under
this Plan due to the death of the Participant shall be paid in the following
order: (a) to the children of the Participant; (b) to the beneficiary of the
Company Paid Life Insurance of the Participant; (c) to the beneficiary of the
Union Carbide Executive Life Insurance of the Participant; (d) to the
beneficiary of any Company-sponsored life insurance policy for which the Company
pays all or part of the premium of the Participant; or (e) to the deceased
Participant's estate.

1.02COMPANY shall mean Union Carbide Corporation and any other entity authorized
to participate under the Plan.

1.03EMPLOYEE shall mean someone who is employed by the Company to perform
personal services in an employer-employee relationship who receives compensation
from the Company other than a retirement benefit, severance pay, retainer, or
fee under contract.

1.04PARTICIPANT shall mean an Employee who is entitled to a Restricted Benefit
under this Plan as determined by the Plan Administrator and any former Employee
who is entitled to a Restricted Benefit under this Plan.

1.05PLAN YEAR shall mean the twelve (12) month period beginning January 1 and
ending December 31.

1.06RESTRICTED BENEFIT shall mean benefits restricted under the exclusive
benefit rule, the inability to grant past service under UCEPP to highly
compensated Employees without meeting the non-discrimination requirements of the
Code, and/or the inability to credit service to Employees while employed by a
controlled group member not covered by UCEPP as more specifically described in
Article III.

1.07RETIREMENT shall mean the date which the Participant commences to receive
benefits under UCEPP.

Additional definitions appear in the Preamble of the Plan.

ARTICLE II
PARTICIPATION

2.01ELIGIBILITY AND PARTICIPATION

Each Employee who is participating in UCEPP and is specifically named by the
Plan Administrator shall be eligible to participate in the Plan. Each named
Employee shall furnish such information and perform such acts as the Company may
require in order to maintain such eligibility.

2.02MEANING OF PARTICIPATION

A Participant in the Plan shall be entitled to receive a Restricted Benefit as
provided in Article III.

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2.03TERMINATION OF PARTICIPATION

An otherwise eligible Employee shall cease to actively participate in the Plan
upon the earlier of the Participant's Retirement, death, termination of
employment, receipt of written notification that he or she is no longer eligible
to participate in the Plan or transfer to an entity covered under The Dow
Chemical Company Executives' Supplemental Retirement Plan. Upon such transfer,
the liability for benefits hereunder shall be transferred to The Dow Chemical
Company Executives' Supplemental Retirement Plan. Thereafter, participation
shall continue only for the purpose of receiving a distribution of those
Restricted Benefits accrued and vested as of the date the Participant ceased to
actively participate in the Plan unless the liability for such benefits has been
transferred as set forth above.

ARTICLE III
RESTRICTED BENEFITS

3.01RESTRICTION DUE TO INABILITY TO GRANT PAST SERVICE UNDER UCEPP TO HIGHLY
COMPENSATED EMPLOYEES WITHOUT MEETING THE NON-DISCRIMINATION REQUIREMENTS OF
§401(a)(4) OF THE CODE

(a)The amount of retirement benefits payable under UCEPP to certain Employees
who transfer from a foreign entity to a U.S. entity covered by the UCEPP may not
include benefits for service rendered while a non-U.S. Employee. The intent of
this Section 3.01 is to provide these Employees, as named by the Plan
Administrator, benefits additional to the Employee's UCEPP benefits, the
benefits being equal to the value of such Employees' accrued benefits under the
foreign plans at the time of transfer, subject to the restrictions in
Section 3.01(b).

(b)The Restricted Benefits payable under Subsection (a) above are subject to the
following:

(i)Restricted Benefits shall be calculated under the terms of UCEPP in effect on
the earlier of (A) termination, (B) Retirement, or (C) death, with the exception
of credited service. Credited service shall be determined according to a method
determined by the Plan Administrator.

(ii)If legally permissible, Participants hereunder shall be required to waive
any retirement benefits payable under any foreign plan. If such a waiver is not
legally permissible, the value of any retirement benefits received under the
foreign plans shall be deducted from any Restricted Benefits payable hereunder.
Such value shall be calculated according to a method determined by the Plan
Administrator.

(iii)A Participant's vested interest in his or her Restricted Benefit calculated
under this Section 3.01 (i.e., vesting percentage) shall be determined in
accordance with the vesting schedule in their current foreign plan. Such vested
interest shall be determined by aggregating service earned under the foreign
plan and UCEPP. In the event a Participant forfeits by waiving all or a portion
of his or her Restricted Benefit due to the provisions of this Section 3.01, no
other Participant shall acquire any right to such forfeited amount except as the
Company in its discretion shall provide.

3.02RESTRICTION DUE TO THE EXCLUSIVE BENEFIT RULE UNDER §401(a) OF THE CODE

(a)The amount of credited service and compensation used to calculate retirement
benefits under UCEPP is limited to the credited service and compensation earned
while an Employee of the Company (including all members of the controlled group
that have adopted UCEPP). The Company, however, transfers Employees to entities
that are not members of the controlled group but with which it is affiliated.
The Company also hires persons from entities that are not affiliated with the
Company. The intent of this Section 3.02 is to provide Employees, as named by
the Plan Administrator, with additional benefits equal to the benefits such
Employee would have earned under UCEPP for his or her full period of employment
with controlled group and non-controlled group entities and, if applicable, any
such service with a non-affiliated company as may be determined by the Plan
Administrator, subject to Section 3.02(b).

(b)The Restricted Benefits payable under Subsection (a) above are subject to the
following:

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(i)Restricted Benefits shall be calculated under the UCEPP formula in effect on
the earlier of (A) termination or (B) Retirement or (C) death, using the
aggregated credited service and compensation earned while an Employee at both
controlled and non-controlled group entities and, if applicable, a
non-affiliated company as determined by the Plan Administrator. This amount
shall be reduced by both the benefit payable under UCEPP and the value of any
retirement benefits payable under any plan of a non-controlled group employer
and, if applicable, a non-affiliated company as determined by the Plan
Administrator.

(ii)The value of any retirement benefits payable under any plan of a
non-controlled group employer and, if applicable, a non-affiliated company as
determined by the Plan Administrator shall be calculated according to a method
determined by the Plan Administrator.

3.03RESTRICTION DUE TO EMPLOYMENT BY A MEMBER OF THE CONTROLLED GROUP NOT
COVERED BY UCEPP

(a)The amount of credited service and compensation used to calculate retirement
benefits under UCEPP is limited to the credited service and compensation earned
while an Employee of the Company (including all members of the controlled group
that have adopted UCEPP). However, Employees may be transferred to entities that
are members of the controlled group not covered by UCEPP. The intent of this
Section 3.03 is to provide such Employees, as named by the Plan Administrator,
with additional benefits equal to the benefits such Employee would have earned
under UCEPP for his or her full period of employment with both the Company and
the member of the controlled group not covered by UCEPP, subject to the
restrictions in Section 3.03(b).

(b)The Restricted Benefits payable under Subsection (a) above are subject to the
following:

(i)Restricted Benefits shall be calculated under the UCEPP formula in effect on
the earlier of (A) termination, (B) Retirement, or (C) death, using the
aggregated credited service and compensation earned while an Employee at both
the Company and the member of the controlled group not covered by UCEPP. This
amount shall be reduced by both the benefit payable under UCEPP and the value of
any retirement benefits payable under any plan of the member of the controlled
group not covered by UCEPP.

(ii)The value of any retirement benefits payable under any plan of the
controlled group member not covered by UCEPP shall be calculated according to a
method determined by the Plan Administrator.

ARTICLE IV
DISTRIBUTION OF RESTRICTED BENEFITS

4.01PAYMENT OF RESTRICTED BENEFITS

(a)Form of Payment

Benefits under the Plan are payable in any of the following forms, as elected by
the Participant:

(i)Standard Option

The Participant's benefit under the Standard Option is payable in the same
optional form as the Participant's UCEPP benefit other than the grandfathered
qualified joint and survivor annuity of the former Non-Contributory Pension Plan
for Employees of Union Carbide Corporation and its Participating Subsidiary
Companies. If such grandfathered option is elected under UCEPP, the benefit
payable hereunder shall be paid as a life only annuity as set forth in UCEPP.
The Standard Option benefit is determined and paid pursuant to the provisions of
UCEPP.

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(ii)Mandatory Lump Sum Form of Benefit Payment

The Lump Sum Form of Benefit Payment is mandatory for Participants with a
Restricted Benefit whose present value, as determined under Section 4.01(a)(ii),
is equal to or less than twenty-five thousand dollars ($25,000). Under this
Mandatory Lump Sum Form of Benefit Payment, the Participant's benefit hereunder
is payable in a single lump sum payment. On or before January 1, 2006,
Participants may roll over such single lump sum payment to The Dow Chemical
Company Elective Deferral Plan. After January 1, 2006, such rollovers will not
be permitted unless the Participant terminated employment prior to March 1, 2004
and has not commenced benefits prior to March 1, 2004. The amount of the
Mandatory Lump Sum Form of Benefit Payment benefit shall be calculated pursuant
to (A) or (B) below.

(A)For Lump Sum Form of Benefit Payments on or before January 1, 2006, the
present value of the Restricted Benefit if paid immediately using the mortality
table specified by the Commissioner of the Internal Revenue Service in Revenue
Ruling 2001-62 and a discount rate equal to the average of the 10 and 20 year
Aaa municipal bonds as published by Moody's or a similar rating service for the
third month prior to the month payments commence

(B)For Lump Sum Form of Benefit Payments after January 1, 2006, the greater of
(1) or (2) below:

(1)the present value of the Restricted Benefit if paid immediately using the
G83U mortality table and an interest rate of eight percent (8%); or

(2)the present value of the Restricted Benefit deferred to age sixty-five
(65) using the mortality table specified by the Commissioner of the Internal
Revenue Service in Revenue Ruling 2001-62 and an interest rate equal to the
yield rate for thirty (30) year Treasury constant maturity securities in the
Federal Reserve Statistical Release effective for the August prior to the Plan
Year of distribution.

(b)Date of Payment

(i)Standard Option

Under the Standard Option, the Participant's benefit hereunder is payable in the
same month as the Participant's UCEPP benefit.

(ii)Mandatory Lump Sum Form of Benefit Payment

Under the Mandatory Lump Sum Form of Benefit Payment, the Participant's benefit
hereunder is payable as soon as administratively possible following the
Participant's termination.

(c)Benefit Payments Payable Upon Death

(i)Death Before Retirement

Under the Standard Option, the survivor benefit hereunder is determined and paid
pursuant to the provisions of UCEPP. If such Participant was subject to the
Mandatory Lump Sum, such lump sum benefit shall be paid to the Participant's
Beneficiary pursuant to (b) above.

(ii)Death After Retirement

In the event the Participant dies after the Participant has started to receive
benefit payments under this Plan, the type and amount of survivor benefits will
vary depending upon the form of benefit election made by the Participant under
Subsection 4.01(a) of the Plan.

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(A)Standard Option

Under the Standard Option, the survivor benefit hereunder is determined and paid
pursuant to the provisions of UCEPP.

(B)Mandatory Lump Sum Form of Benefit Payment

Under the Mandatory Lump Sum Form of Benefit Payment, if the Participant has
received the single lump sum payment, no other benefits are payable hereunder.
If the Participant dies prior to receiving such single lump sum payment, the
single lump sum payment will be made to the Participant's Beneficiary.

4.02CHANGE IN CONTROL

Change in Control shall mean a change in control of the Company of a nature that
would be required to be reported in response to Item 5(f) of Schedule 14A of
Regulation 14A promulgated under the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), whether or not the Company is then subject to such
reporting requirement, provided that, without limitation, a Change in Control
shall be deemed to have occurred if:

(a)any individual, partnership, firm, corporation, association, trust,
unincorporated organization or other entity, or any syndicate or group deemed to
be a person under Section 14(d)(2) of the Exchange Act, is or becomes the
"beneficial owner" (as defined in Rule 13d-3 of the General Rules and
Regulations under the Exchange Act), directly or indirectly, of securities of
the Company representing 20% or more of the combined voting power of the
Company's then outstanding securities entitled to vote in the election of
directors of the Company; or

(b)during any period of two (2) consecutive years (not including any period
prior to the execution of this Plan), individuals who at the beginning of such
period constitute the Board of Directors and any new directors, whose election
by the Board of Directors or nomination for election by the Company's
stockholders was approved by a vote of at least three quarters (3/4) of the
directors then still in office who either were directors at the beginning of the
period or whose election or nomination for election was previously so approved,
cease for any reason to constitute a majority thereof. A change in control shall
not be deemed to be a Change in Control for purposes of this Plan if the Board
of Directors has approved such change in control prior to either:

(i)the occurrence of any of the events described in the foregoing clauses
(a) and (b), or

(ii)the commencement by any person other than the Company of a tender offer for
the Common Stock.

In the event of such Change in Control, the vested Restricted Benefits under
Sections 3.01, 3.02 and 3.03 shall become payable immediately and shall be paid
as a single lump sum payment within ninety (90) days of the Change in Control.
The value of such single lump sum payment shall be the present value of the
monthly Restricted Benefit as of the date of Change in Control calculated
pursuant to Section 4.01(a)(ii)(A).

ARTICLE V
RESTRICTED BENEFITS FUND

5.01FINANCING OF RESTRICTED BENEFITS

The entire cost of providing benefits under the Plan shall be paid by the
Company out of its current operating budget, and the Company shall not be
required under any circumstances to fund its obligations under the Plan.
Notwithstanding the foregoing, the Company may, at its sole option, informally
fund its obligations under the Plan in whole or in part by the creation of book
reserves, the establishment of a grantor trust, the purchase of insurance and
other assets, or by other means. In no event shall any Participant or
Beneficiary have any incidents of ownership to any such insurance contracts or
other assets. In addition, no Participant or Beneficiary shall be named a
beneficiary under any such insurance contract. If the Company informally funds
the Plan, in whole or in part, the manner of such

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informal funding and the continuance or discontinuance of such informal funding
shall be the sole decision of the Company.

5.02GENERAL CREDITOR

The Participant, and/or Beneficiary, shall be regarded as an unsecured general
creditor of the Company with respect to any rights derived by the Participant,
and/or Beneficiary, from the existence of this Plan. Title to and beneficial
ownership of any Company assets (including any assets that may be held in trust)
which may be used to satisfy the Company's obligation for payment of Restricted
Benefits shall remain solely the property of the Company.

5.03LIABILITY OF COMPANY

Nothing in this Plan shall constitute the creation of a trust or other fiduciary
relationship between the Company, its agents, representatives or other Employees
dealing with the Plan and the Participant, Beneficiary or any other person. The
obligations of the Company under the Plan shall be an unfunded and unsecured
promise to pay.

5.04ASSIGNMENT

No rights under this Plan may be assigned, transferred, pledged or encumbered by
any Participant or Beneficiary. The obligations and rights of the Company under
this Plan may be encumbered in the event of the Company's insolvency.

ARTICLE VI
MISCELLANEOUS

6.01PLAN IS BINDING

This Plan shall be binding upon and inure to the benefit of the Company,
participating Employees and their respective successors, assigns, heirs,
personal representatives, executors, administrators, Beneficiaries, and
legatees.

6.02ENTIRE PLAN

This document constitutes the entire Plan and no representations or other
actions by a Company Employee or representative may modify the rights and
obligations set forth in the Plan.

6.03NO GUARANTEE OF EMPLOYMENT

Nothing in this Plan shall be construed as an employment contract or as a
guarantee of employment for any period of time.

6.04GOVERNING LAW

In the event that ERISA does not preempt state law, the state law of Michigan
applies.

6.05TERMINATION

The Company reserves the right to terminate the Plan completely subject to the
conditions set forth below. Such termination shall have prospective application
only and shall not reduce or impair a Participant's right to Restricted Benefits
accrued and vested as of the date of termination. Each Participant shall receive
written note of the termination of the Plan describing the action taken in
detail.

6.06WITHHOLDING TAXES

The Company shall have the right to withhold taxes from any payments made
pursuant to the Plan, or make such other provisions as it deems necessary or
appropriate to satisfy its obligations to withhold federal, state, local or
foreign income or other taxes incurred by reason of payments pursuant to the
Plan. In lieu thereof, the Company shall have the

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right, to the extent permitted by law, to withhold the amount of such taxes from
any other sums due or to become due from the Company to the Participant or any
Beneficiary upon such terms and conditions as the Company may prescribe.

6.07OVERPAYMENTS

If any overpayment of benefits is made under this Plan, the amount of the
overpayment may be set-off against future amounts payable to or on account of
the person who received the overpayment until the overpayment has been
recovered. The foregoing remedy is not intended to be exclusive.

ARTICLE VII
PLAN ADMINISTRATION

7.01ADMINISTRATION

This Plan is administered by the Board of Directors of the Company who may
delegate any or all of its responsibilities to a Plan Administrator. The Plan
Administrator is authorized to amend the Plan, construe and interpret all Plan
provisions, to adopt rules concerning the implementation of Plan provisions, and
to make any determinations necessary or appropriate hereunder which shall be
binding and conclusive on all parties except as otherwise provided by the Plan
Administrator. Any amendment shall have prospective application only and shall
not reduce or impair a Participant's right to Restricted Benefits accrued and
vested as of the date such amendment is made. Each Participant shall receive
written notice of the amendment or termination of the Plan describing the action
taken in detail.

7.02CLAIMS SUBMISSION AND REVIEW PROCEDURE

Any disputed claim for benefits must be submitted in writing to the Company. In
the event that any claim for benefits hereunder is denied (in whole or in part),
the claimant shall receive from the Company, within 90 days after its receipt of
the benefit claim, a written notice setting forth the specific reasons for
denial, with specific reference to pertinent provisions of this Plan, unless
special circumstances require an extension of time for processing the claim. The
notice shall be written in a manner calculated to be understood by the claimant.
If an extension of time is required, written notice of the extension shall be
furnished to the claimant prior to the termination of the initial 90-day period.
In no event shall such extension exceed a period of 90 days from the end of the
initial period. The claimant may make a written request for review of any such
denial by the Company within 60 days following the date of such denial. The
claimant shall be entitled to submit such issues or comments, in writing, as he
or she shall consider relevant to a determination of the claim. The Plan
Administrator shall notify the claimant of its decision in writing no later than
60 days following receipt of the claimant's request, unless specific
circumstances require an extension of time for processing, in which case the
Plan Administrator's decision shall be rendered no later than 120 days after
receipt of such request for review. The interpretations and construction of the
Plan by the Plan Administrator shall be binding and conclusive on all persons
and for all purposes. Notwithstanding the above, any disagreement may be
submitted to the Board of Directors or the Plan Administrator for resolution
provided that all interested parties agree to be bound by the decision. No
member of the Board of Directors, Company management or the Plan Administrator
shall be liable to any person for any action taken hereunder except for those
actions undertaken with lack of good faith.

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PART B

FOR A SELECT GROUP OF MANAGEMENT OR
HIGHLY COMPENSATED EMPLOYEES, BOARD MEMBERS,
AND EMPLOYEES WHOSE BENEFITS ARE STATUTORILY LIMITED

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ARTICLE I
DEFINITIONS

1.01AVERAGE COMPENSATION for purposes of the Supplemental Retirement Benefit of
a Participant who was in the Union Carbide Compensation Deferral Program on
February 6, 2001 and who shall attain at least age 50 and have at least 10 years
of Eligibility Service, as defined under UCEPP, as of or before December 31,
2005 and Participants who terminated employment prior to March 1, 2004 and after
February 6, 2003 and had not commenced benefits as of March 1, 2004, shall equal
the highest three year average compensation (HC3A) as defined in UCEPP but using
Compensation as defined in Section 1.04 without regard to incentive compensation
plus the highest three year average, as defined in the former Enhanced
Retirement Income Plan (attached as Exhibit I), of incentive compensation
averaged separately. Incentive compensation for calendar years prior to 2004
shall have the same meaning as defined in the former Enhanced Retirement Income
Plan, and for calendar years 2004 and 2005, incentive compensation shall mean
Compensation as defined in Section 1.04 without regard to either deferred or
paid base compensation. This Average Compensation shall be used to calculate
benefits as specified under Section 3.01.

1.02BENEFICIARY shall mean that person or persons designated by the Participant
to receive a distribution of any amounts payable under this Plan due to the
death of the Participant. The beneficiary of a Participant shall be deemed to be
such Participant's spouse, if married, or their domestic partner, if in a
domestic partner relationship as approved by the Company, unless such spouse
agrees in writing to waive this right (such waiver does not apply to a domestic
partner). If the Participant is not married or in an approved domestic partner
relationship and fails to designate a Beneficiary, the amounts payable under
this Plan due to the death of the Participant shall be paid in the following
order: (a) to the children of the Participant; (b) to the beneficiary of the
Company Paid Life Insurance of the Participant; (c) to the beneficiary of the
Union Carbide Executive Life Insurance of the Participant; (d) to the
beneficiary of any Company-sponsored life insurance policy for which the Company
pays all or part of the premium of the Participant; or (e) to the deceased
Participant's estate.

1.03COMPANY shall mean Union Carbide Corporation and any other entity authorized
to participate under the Plan.

1.04COMPENSATION shall mean:

(a)compensation as defined under UCEPP without regard to Code limitations,

(b)compensation, if any, granted by the Board of Directors of the Company
recognized for supplemental pension purposes but excluded under UCEPP, which
shall include deferred compensation, and/or

(c)non-covered compensation, if any, as shall be deemed by the Board of
Directors of the Company, such as deferred compensation, the value of deferred
stock, dividend units, and/or restricted stock awarded under circumstances other
than those described in Subsection (b) of this Section 1.04 and which do not
constitute compensation for purposes of UCEPP.

1.05EMPLOYEE shall mean someone who is employed by the Company.

1.06PARTICIPANT shall mean an Employee:

(a)who is a Board member who is an officer or Employee of the Company and who
may relinquish line responsibility,

(b)whose benefits under UCEPP are limited by the Employee Retirement Income
Security Act of 1974 (ERISA), or

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(c)who is in a select group of management or is a highly compensated employee,
as determined by the Plan Administrator, who receives forms of compensation that
do not constitute compensation as defined in UCEPP.

PARTICIPANT shall also mean a former participant in the program prior to this
restatement who terminated prior to March 1, 2004 and had not commenced benefits
as of March 1, 2004.

1.07PLAN YEAR shall mean the twelve (12) month period beginning January 1 and
ending December 31.

1.08RETIREMENT shall mean the date which the Participant commences to receive
benefits under UCEPP.

1.09SUPPLEMENTAL RETIREMENT BENEFITS shall mean benefits which are reduced under
UCEPP and ESP due to current and/or future statutory limitations and, if
applicable, non-separate averaging of Compensation and which are not otherwise
provided by any other plan maintained by the Company as more specifically set
forth in Section 3.01.

        Additional definitions appear in the Preamble of the Plan.

ARTICLE II
PARTICIPATION

2.01ELIGIBILITY AND PARTICIPATION

Each Employee who is a member of a select group of management or a highly
compensated employee, board members and/or an Employee whose benefits are
statutorily limited shall be eligible to participate in the Plan. Each former
participant in the program prior to restatement who terminated prior to March 1,
2004 and had not commenced benefits as of March 1, 2004 shall be a Participant
hereunder. Each such Employee or Participant shall furnish such information and
perform such acts as the Company may require in order to maintain such
eligibility.

2.02MEANING OF PARTICIPATION

A Participant in the Plan shall be entitled to receive a Supplemental Retirement
Benefit as provided in Article III.

2.03TERMINATION OF PARTICIPATION

An otherwise eligible Employee shall cease to actively participate in the Plan
upon the earlier of the Participant's Retirement, death, termination of
employment, receipt of written notification that he or she is no longer eligible
to participate in the Plan or transfer to an entity covered under The Dow
Chemical Company Executives' Supplemental Retirement Plan. Upon such transfer,
the liability for benefits hereunder shall be transferred to The Dow Chemical
Company Executives' Supplemental Retirement Plan. Thereafter, participation
shall continue only for the purpose of receiving a distribution of those
Supplemental Retirement Benefits accrued and vested as of the date the
Participant ceased to actively participate in the Plan unless the liability for
such benefits has been transferred as set forth above.

ARTICLE III
SUPPLEMENTAL RETIREMENT BENEFITS

3.01SUPPLEMENTAL RETIREMENT BENEFITS

The amount of Supplemental Retirement Benefits payable to a Participant under
Part B of this Plan equals the benefit which would be payable to or on behalf of
the Participant under UCEPP if Compensation as defined in Section 1.04 of the
Plan were substituted for compensation as defined in UCEPP and the provisions of
UCEPP providing for the limitation of benefits in accordance with Sections 415
and 401(a)(17) of the Internal Revenue Code were inapplicable, less the benefit
actually payable to or on behalf of the Participant under UCEPP (and of the
benefits under any other private retirement plan deducted therefrom pursuant to
Section 9 of Article IV of UCEPP).

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The amount of Supplemental Retirement Benefits payable to a Participant who was
in the Union Carbide Compensation Deferral Program on February 6, 2001 and who
shall attain at least age 50 and have at least 10 years of Eligibility Service,
as defined under UCEPP, as of or before December 31, 2005 and Participants who
terminated employment prior to March 1, 2004 and after February 6, 2003 and had
not commenced benefits as of March 1, 2004 equals the greater of the benefit
calculated under the above paragraph or the benefit calculated as of the earlier
of December 31, 2005 or termination which would be payable to or on behalf of
the Participant under UCEPP if Average Compensation as defined in Section 1.01
of the Plan were substituted for compensation as defined in UCEPP under the
formula of Section 4.1(a)(iii) or Section 4.5(c) of UCEPP, as applicable, and
the provisions of UCEPP providing for the limitation of benefits in accordance
with Sections 415 and 401(a)(17) of the Internal Revenue Code were inapplicable,
less the benefit actually payable to or on behalf of the Participant under UCEPP
(and of the benefits under any other private retirement plan deducted therefrom
pursuant to Section 9 of Article IV of UCEPP).

The amount of Supplemental Retirement Benefits payable to Participants who
terminated employment prior to February 7, 2003 and had not commenced benefits
as of March 1, 2004 are determined pursuant to the terms of the program in
effect at termination.

If a Participant in this Plan is not a Participant in UCEPP, but is covered by
another retirement plan or plans maintained by the Company or a subsidiary, a
Supplemental Retirement Benefit may be computed and paid based as near as
practicable upon the principles set forth in this Section 3.01 as shall be
determined by the Plan Administrator.

A Participant's vested interest in his or her Supplemental Retirement Benefit
calculated under this Section 3.01 (i.e., vesting percentage) shall be
determined in accordance with the vesting schedule in UCEPP.

ARTICLE IV
DISTRIBUTION AND FORM OF
SUPPLEMENTAL RETIREMENT BENEFITS

4.01PAYMENT OF SUPPLEMENTAL RETIREMENT BENEFITS

(a)Form of Payment

Benefits under the Plan are payable in any of the following forms, as elected by
the Participant:

(i)Standard Option

The Participant's benefit under the Standard Option is payable in the same
optional form as the Participant's UCEPP benefit other than the grandfathered
qualified joint and survivor annuity of the former Non-Contributory Pension Plan
for Employees of Union Carbide Corporation and its Participating Subsidiary
Companies. If such grandfathered option is elected under UCEPP, the benefit
payable hereunder shall be paid as a life only annuity as set forth in UCEPP.
The Standard Option benefit is determined and paid pursuant to the provisions of
UCEPP.

(ii)Lump Sum Form of Benefit Payment

(A)Mandatory Lump Sum

Subject to Paragraph (d) of this Section 4.01, the Lump Sum Form of Benefit
Payment is mandatory for Participants with a Supplemental Benefit whose present
value, as determined under Section 4.01(a)(ii)(A), is equal to or less than
twenty-five thousand dollars ($25,000). Under this Mandatory Lump Sum Form of
Benefit Payment, the Participant's benefit hereunder is payable in a single lump
sum payment. On or before January 1, 2006, Participants may roll over such
single lump sum payment to The Dow Chemical Company Elective Deferral Plan.
After January 1, 2006, such rollovers will not be permitted unless the
Participant terminated employment prior to March 1, 2004 and has not commenced
benefits prior to March 1, 2004. The amount of the Mandatory Lump Sum Form of
Benefit Payment benefit shall be calculated pursuant to (1) or (2) below.

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(1)For Lump Sum Form of Benefit Payments on or before January 1, 2006, the
present value of the Supplemental Benefit if paid immediately using the
mortality table specified by the Commissioner of the Internal Revenue Service in
Revenue Ruling 2001-62 and a discount rate equal to the average of the 10 and
20 year Aaa municipal bonds as published by Moody's or a similar rating service
for the third month prior to the month payments commence.

(2)For Lump Sum Form of Benefit Payments after January 1, 2006, the greater of
a. or b. below:

  a. the present value of the Supplemental Benefit if paid immediately using the
G83U mortality table and an interest rate of eight percent (8%); or
 
b.
the present value of the Restricted Benefit deferred to age sixty-five
(65) using the mortality table specified by the Commissioner of the Internal
Revenue Service in Revenue Ruling 2001-62 and an interest rate equal to the
yield rate for thirty (30) year Treasury constant maturity securities in the
Federal Reserve Statistical Release effective for the August prior to the Plan
Year of distribution.

(B)Optional Lump Sum

Subject to Paragraph (d) of this Section 4.01, the Optional Lump Sum Form of
Benefit Payment is available to Participants who were in the Union Carbide
Compensation Deferral Program on February 6, 2001 and who shall attain at least
age 50 and have at least 10 years of Eligibility Service, as defined under
UCEPP, as of or before December 31, 2005 until January 1, 2006 and Participants
who terminated employment prior to March 1, 2004 and have not commenced benefits
prior to March 1, 2004. Under this Optional Lump Sum Form of Benefit Payment,
the Participant's benefit hereunder is payable in a single lump sum payment. The
amount of the Optional Lump Sum Form of Benefit Payment benefit shall be equal
to the present value of the Supplemental Retirement Benefit if paid immediately
using a discount rate equal to the average of 10 and 20 year Aaa municipal bonds
as published by Moody's or a similar rating service for the third month prior to
the month payments commence and the mortality table specified by the
Commissioner of the Internal Revenue Service in Revenue Ruling 2001-62. On or
before January 1, 2006, Participants, may roll over such single lump sum payment
to The Dow Chemical Company Elective Deferral Plan. After January 1, 2006, such
rollovers will not be permitted unless the Participant terminated employment
prior to March 1, 2004 and has not commenced benefits prior to March 1, 2004.

(b)Date of Payment

(i)Standard Option

Under the Standard Option, the Participant's benefit hereunder is payable in the
same month as the Participant's UCEPP benefit.

(ii)Lump Sum Form of Benefit Payment

(A)Under the Mandatory Lump Sum Form of Benefit Payment, the Participant's
benefit hereunder is payable as soon as administratively possible following the
Participant's termination.

(B)If the Optional Lump Sum Form of Benefit is elected by the Participant, the
Participant's benefit hereunder is payable under the Standard Option beginning
in the same month as the Participant's UCEPP benefit until the July of the year
following the month payments commence, at which time the remaining value of the
Lump Sum will be paid.

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(c)Benefit Payments Payable Upon Death

(i)Death Before Retirement

Under the Standard Option, the survivor benefit hereunder is determined and paid
pursuant to the provisions of UCEPP. If such Participant was subject to the
Mandatory Lump Sum, such lump sum benefit shall be paid to the Participant's
Beneficiary pursuant to 4.01(b)(ii)(A) above.

(ii)Death After Retirement

In the event the Participant dies after the Participant has started to receive
benefit payments under this Plan, the type and amount of survivor benefits will
vary depending upon the form of benefit election made by the Participant under
Subsection 4.01(a) of the Plan.

(A)Standard Option

Under the Standard Option, the survivor benefit hereunder is determined and paid
pursuant to the provisions of UCEPP.

(B)Mandatory Lump Sum Form of Benefit Payment

Under the Mandatory Lump Sum Form of Benefit Payment, if the Participant has
received the single lump sum payment, no other benefits are payable hereunder.
If the Participant dies prior to receiving such single lump sum payment, the
single lump sum payment will be made to the Participant's Beneficiary.

(C)Optional Lump Sum Form of Benefit Payment

Under the Optional Lump Sum Form of Benefit Payment, if the Participant has
received the single lump sum payment, no other benefits are payable hereunder.
If the Participant dies prior to the July of the year following the month
payments commence, such Participant's benefit will continue to be paid as set
forth in 4.01(b)(ii)(B); that is payable under the Standard Option beginning in
the same month as the UCEPP benefit began until the July of the year following
the month payments commence, at which time the remaining value of the Lump Sum
will be paid to the Beneficiary.

(d)Miscellaneous

(i)No election

Participants, entitled to make an election of the Optional Lump Sum Form of
Benefit Payment under the Plan, who do not make an election of such Lump Sum
Form of Benefit Payment in writing prior to termination from employment,
Retirement, or death, shall be deemed to have elected the Standard Option.

(ii)Small Benefits

At the time of Retirement, if the present value of a Participant's Supplemental
Retirement Benefits, as determined under this Section 4.01(a)(ii)(A) above, is
equal to or less than twenty-five thousand dollars ($25,000), the benefits will
be paid under the Mandatory Lump Sum Option.

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4.02CHANGE IN CONTROL

Change in Control shall mean a change in control of the Company of a nature that
would be required to be reported in response to Item 5(f) of Schedule 14A of
Regulation 14A promulgated under the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), whether or not the Company is then subject to such
reporting requirement, provided that, without limitation, a Change in Control
shall be deemed to have occurred if:

(a)any individual, partnership, firm, corporation, association, trust,
unincorporated organization or other entity, or any syndicate or group deemed to
be a person under Section 14(d)(2) of the Exchange Act, is or becomes the
"beneficial owner" (as defined in Rule 13d-3 of the General Rules and
Regulations under the Exchange Act), directly or indirectly, of securities of
the Company representing 20% or more of the combined voting power of the
Company's then outstanding securities entitled to vote in the election of
directors of the Company; or

(b)during any period of two (2) consecutive years (not including any period
prior to the execution of this Plan), individuals who at the beginning of such
period constitute the Board of Directors and any new directors, whose election
by the Board of Directors or nomination for election by the Company's
stockholders was approved by a vote of at least three quarters (3/4) of the
directors then still in office who either were directors at the beginning of the
period or whose election or nomination for election was previously so approved,
cease for any reason to constitute a majority thereof. A change in control shall
not be deemed to be a Change in Control for purposes of this Plan if the Board
of Directors has approved such change in control prior to either:

(i)the occurrence of any of the events described in the foregoing clauses
(a) and (b), or

(ii)the commencement by any person other than the Company of a tender offer for
the Common Stock.

In the event of such Change in Control, the vested Supplemental Retirement
Benefits under Section 3.01 shall become payable immediately and shall be paid
as a single lump sum payment within ninety (90) days of the Change in Control.
The value of such single lump sum payment shall be the present value of the
monthly Supplemental Retirement Benefits as of the date of Change in Control
calculated pursuant to Section 4.01(a)(ii)(A).

ARTICLE V
SUPPLEMENTAL RETIREMENT BENEFITS FUND

5.01FINANCING OF SUPPLEMENTAL RETIREMENT BENEFITS

The entire cost of providing benefits under the Plan shall be paid by the
Company out of its current operating budget, and the Company shall not be
required under any circumstances to fund its obligations under the Plan.
Notwithstanding the foregoing, the Company may, at its sole option, informally
fund its obligations under the Plan in whole or in part by the creation of book
reserves, the establishment of grantor trust, the purchase of insurance and
other assets, or by other means. In no event shall any Participant or
Beneficiary have any incidents of ownership to any such insurance contracts or
other assets. In addition, no Participant or Beneficiary shall be named a
beneficiary under any such insurance contract. If the Company informally funds
the Plan, in whole or in part, the manner of such informal funding and the
continuance or discontinuance of such informal funding shall be the sole
decision of the Company.

5.02GENERAL CREDITOR

The Participant, and/or Beneficiary, shall be regarded as an unsecured general
creditor of the Company with respect to any rights derived by the Participant
and/or Beneficiary, from the existence of this Plan. Title to and beneficial
ownership of any Company assets (including any assets that may be held in trust)
which may be used to satisfy the Company's obligation for payment of
Supplemental Retirement Benefits shall remain solely the property of the
Company.

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5.03LIABILITY OF COMPANY

Nothing in this Plan shall constitute the creation of a trust or other fiduciary
relationship between the Company, its agents, representatives or other Employees
dealing with the Plan and the Participant, Beneficiary or any other person. The
obligations of the Company under the Plan shall be an unfunded and unsecured
promise to pay.

5.04ASSIGNMENT

No rights under this Plan may be assigned, transferred, pledged or encumbered by
any Participant or Beneficiary. The obligations and rights of the Company under
this Plan may be encumbered in the event of the Company's insolvency.

ARTICLE VI
MISCELLANEOUS

6.01PLAN IS BINDING

This Plan shall be binding upon and inure to the benefit of the Company,
participating Employees and their respective successors, assigns, heirs,
personal representatives, executors, administrators, Beneficiaries and legatees.

6.02ENTIRE PLAN

This document constitutes the entire Plan and no representations or other
actions by a Company Employee or representative may modify the rights and
obligations set forth in the Plan.

6.03NO GUARANTEE OF EMPLOYMENT

Nothing in this Plan shall be construed as an employment contract or as a
guarantee of employment for any period of time.

6.04GOVERNING LAW

In the event that ERISA does not preempt state law, the state law of Michigan
applies.

6.05TERMINATION

The Company reserves the right to terminate the Plan completely subject to the
conditions set forth below. Such termination shall have prospective application
only and shall not reduce or impair a Participant's right to Supplemental
Retirement Benefits accrued and vested as of the date of termination. Each
Participant shall receive written note of the termination of the Plan describing
the action taken in detail.

6.06WITHHOLDING TAXES

The Company shall have the right to withhold taxes from any payments made
pursuant to the Plan, or make such other provisions as it deems necessary or
appropriate to satisfy its obligations to withhold federal, state, local or
foreign income or other taxes incurred by reason of payments pursuant to the
Plan. In lieu thereof, the Company shall have the right, to the extent permitted
by law, to withhold the amount of such taxes from any other sums due or to
become due from the Company to the Participant or any Beneficiary upon such
terms and conditions as the Company may prescribe.

6.07OVERPAYMENTS

If any overpayment of benefits is made under this Plan, the amount of the
overpayment may be set-off against future amounts payable to or on account of
the person who received the overpayment until the overpayment has been
recovered. The foregoing remedy is not intended to be exclusive.

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ARTICLE VII
PLAN ADMINISTRATION

7.01ADMINISTRATION AND AMENDMENT

This Plan is administered by the Board of Directors of the Company who may
delegate any or all of its responsibilities to a Plan Administrator. The Plan
Administrator is authorized to amend the Plan, construe and interpret all Plan
provisions, to adopt rules concerning the implementation of Plan provisions, and
to make any determinations necessary or appropriate hereunder which shall be
binding and conclusive on all parties except as otherwise provided by the Plan
Administrator. Any amendment shall have prospective application only and shall
not reduce or impair a Participant's right to Supplemental Retirement Benefits
accrued and vested as of the date such amendment is made. Each Participant shall
receive written notice of the amendment or termination of the Plan describing
the action taken in detail.

7.02CLAIMS SUBMISSION AND REVIEW PROCEDURE

Any disputed claim for benefits must be submitted in writing to the Company. In
the event that any claim for benefits hereunder is denied (in whole or in part),
the claimant shall receive from the Company, within 90 days after its receipt of
the benefit claim, a written notice setting forth the specific reasons for
denial, with specific reference to pertinent provisions of this Plan, unless
special circumstances require an extension of time for processing the claim. The
notice shall be written in a manner calculated to be understood by the claimant.
If an extension of time is required, written notice of the extension shall be
furnished to the claimant prior to the termination of the initial 90-day period.
In no event shall such extension exceed a period of 90 days from the end of the
initial period. The claimant may make a written request for review of any such
denial by the Company within 60 days following the date of such denial. The
claimant shall be entitled to submit such issues or comments, in writing, as he
or she shall consider relevant to a determination of the claim. The Plan
Administrator shall notify the claimant of its decision in writing no later than
60 days following receipt of the claimant's request, unless specific
circumstances require an extension of time for processing, in which case the
Plan Administrator's decision shall be rendered no later than 120 days after
receipt of such request for review. The interpretations and construction of the
Plan by the Plan Administrator shall be binding and conclusive on all persons
and for all purposes. Notwithstanding the above, any disagreement may be
submitted to the Board of Directors or the Plan Administrator for resolution
provided that all interested parties agree to be bound by the decision. No
member of the Board of Directors, Company management, or the Plan Administrator
shall be liable to any person for any action taken hereunder except for those
actions undertaken with lack of good faith.

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QuickLinks

Union Carbide Corporation Executives' Supplemental Retirement Plan