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                                                                   EXHIBIT 10.20

                         CLARK REFINING HOLDINGS INC.
                           1999 STOCK INCENTIVE PLAN

     1.   OBJECTIVES.

     This Clark Refining Holdings Inc. 1999 Stock Incentive Plan is designed to
attract and retain executives and other selected employees whose skills and
talents are important to the operations of Clark Refining Holdings Inc. and its
subsidiaries (together, as more fully defined herein, the "Company") and reward
them for making major contributions to the success of the Company.  These
objectives are accomplished by making awards under the Plan, thereby providing
Participants with a proprietary interest in the growth and performance of the
Company.

     2.   DEFINITIONS.

     "Award" - The grant of a Stock Option to a Plan Participant pursuant to
such terms, conditions, requirements and limitations as the Board may establish
in order to fulfill the objectives of the Plan.

     "Award Agreement" - Any agreement or agreements between the Company and a
Participant that sets forth terms, conditions, requirements and limitations
applicable to or in connection with an Award.

     "Blackstone" means The Blackstone Group, Blackstone Capital Partners III
Merchant Banking Fund L.P, Blackstone Offshore Partners III L.P. and Blackstone
Family Investment Partnership III L.P., and their respective affiliates,
subsidiaries and general partners.

     "Board" - The Board of Directors of Clark Holdings.

     "Capital Stock" or "stock" - The Common Stock, $.01 par value per share, of
Clark Holdings.

     "Change in Control" - A change in control shall be deemed to have occurred
if any "person" (as such term is used in Sections 13(d) and 14(d) of the 1934
Act), other than Blackstone, is or becomes the "beneficial owner" (as defined in
Rule 13d-3 under the 1934 Act), directly or indirectly, of securities of Clark
Holdings representing 50% or more of the combined voting power of its then
outstanding securities entitled to vote in the election of directors.

     "Clark Holdings" - Clark Refining Holdings Inc., a Delaware corporation.

     "Code" - The Internal Revenue Code of 1986, as amended from time to time.

     "Committee" - The Compensation Committee of the Board (if any) or such
other committee as may be designated by the Board to administer the Plan;
provided, however, that the Committee (a) shall be composed solely of two or
more non-employee directors, as defined in Rule 16(b)-3(b)(3) under the 1934
Act, and (b) shall be constituted to permit Awards under the Plan to qualify for
exemption under the 1934 Act.

     "Company" - Clark Holdings and its subsidiaries including subsidiaries of
subsidiaries and partnerships and other business ventures in which it has a
significant equity interest, as determined in the sole discretion of the Board.

     "Disability" - A long-term disability as determined pursuant to the
Company's Long-Term Disability Plan.
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     "Fair Market Value" -  With respect to Capital Stock, Awards or other
property, the fair market value of such Capital Stock, Awards or other property
as determined from time to time by the Board in good faith.  Unless otherwise
determined by the Board, (a) if the Capital Stock is traded on NASDAQ, the Fair
Market Value of Capital Stock as of any date shall be the closing sale price on
that date of a share of Capital Stock as reported in the NASDAQ National Market
Issues quotations of the Midwest Edition of the Wall Street Journal, or (b) if
the Capital Stock is traded on the New York Stock Exchange, the Fair Market
Value of Capital Stock as of any date shall be the closing sale price on that
date of a share of Capital Stock as reported on the New York Stock Exchange
Composite Tape (or, if the Capital Stock is not traded on NASDAQ or the New York
Stock Exchange, as applicable, on such date, on the next following date on which
it is so traded).

     "Net Stock Option Value" means, with respect to any shares of Capital Stock
subject to a Stock Option, an amount equal to the excess of (a) the Fair Market
Value of such shares over (b) the exercise price of such Stock Option with
respect to such shares.

     "1934 Act" - The Securities Exchange Act of 1934, as amended from time to
time.

     "Plan" - This Clark Refining Holdings Inc. 1999 Stock Incentive Plan, as
amended from time to time.

     "Participant" - An employee of the Company to whom an Award has been made
under the Plan.

     "Qualified Performance-Based Award" means an Award designated as such by
the Board at or prior to the time of grant, based upon a determination that the
Committee intends for such Award to qualify for the Section 162(m) Exemption.

     "Rule 16b-3" means Rule 16b-3, as from time to time amended and applicable
to Participants, promulgated by the SEC under Section 16 of the 1934 Act.

     "Stock Option" means the right to purchase a specified number of shares of
Capital Stock, granted pursuant to Section 7(a) of the Plan.

     "Stock Option Shares" means shares of Capital Stock acquired pursuant to
Stock Options.

     "SEC" means the United States Securities and Exchange Commission.

     "Section 162(m) Exemption" means the exemption from the limitation on
deductibility imposed by Section 162(m) of the Code that is set forth in Section
162(m)(4)(C) of the Code.

     3.   ELIGIBILITY.

     Executives and other employees of the Company eligible for an Award under
the Plan are those who hold positions of responsibility and whose performance,
in the judgment of the Board or the management of the Company, can have a
significant effect on the success of the Company.

     4.   CAPITAL STOCK AVAILABLE FOR AWARDS.

     The number of shares of Capital Stock that may be issued or delivered under
the Plan for Awards granted during the term of the Plan is 2,215,250 shares.
Such shares may consist of Capital Stock which is authorized and unissued and
has been authorized by the Board to be issued under the Plan or Capital Stock
which is authorized and issued and has been acquired by or on behalf of the
Company or the Plan and is available for Awards under the Plan.  Capital Stock
related to Awards that are forfeited, terminated, expire unexercised, settled in
cash in lieu of stock or in such manner that all or some of the shares covered
by an Award are not issued or delivered to a Participant shall become available
for Awards, upon determination of such availability by the Board following
consultation with the Chief Executive Officer of the Company.

                                      -2-
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     5.   ADMINISTRATION.

     The Plan shall be administered by the Board, which shall have full and
exclusive power to interpret the Plan, to grant waivers of Award restrictions
and to adopt such rules, regulations and guidelines for carrying out the Plan as
it may deem necessary or proper, all of which powers shall be executed in the
best interest of the Company and in keeping with the objectives of the Plan.
These powers include, but are not limited to, the adoption of modifications,
amendments, procedures, subplans and the like as are necessary to comply with
provisions of the laws and regulations of the jurisdictions in which the Company
operates in order to assure the viability of Awards granted under the Plan and
to enable Participants regardless of where employed to receive advantages and
benefits under the Plan and such laws and regulations.

     6.   DELEGATION OF AUTHORITY.

     The Board may delegate to the Committee or to the Chief Executive Officer
or other senior officers of the Company its duties under the Plan pursuant to
such conditions or limitations as the Board may establish, except (a) that only
the Board or the Committee may select, and grant Awards to, Participants who are
subject to Section 16 of the 1934 Act and (b) to the extent that the grant or
exercise of such authority would cause any Award or transaction to fail to
qualify for exemption under Rule 16b-3.

     7.   AWARDS.

     The Board shall determine who may participate in the Plan and the number
and type of Awards to be made to each Participant and shall set forth in the
related Award Agreement or other appropriate manner the terms, conditions,
requirements and limitations applicable to each Award.  Awards may be granted
singly or in combination.  Awards may also be made in combination or in tandem
with, in replacement of, or as alternatives to, grants or rights under any other
employee plan of the Company, including the plan of any acquired entity.  The
Board may make the following type of Awards: stock options; i.e., rights to
purchase a specified number of shares of Capital Stock the purchase price of
which shall be determined by the Board.  No Stock Option shall be exercisable
more than ten years after the date of its grant.

     No Award shall confer on any Participant any of the rights of a shareholder
of the Company unless and until shares of Capital Stock are duly issued or
transferred to the Participant in accordance with the terms of the Award.

     No Participant, officer, employee or director shall have any claim to be
granted any Award under the Plan, and there is no obligation for uniformity of
treatment of Participants or any other persons.  Nothing contained in the Plan
or any Award Agreement shall confer, and no grant of an Award shall be construed
as conferring, upon any employee any right to continue in the employ of the
Company or to interfere in any way with the right of the Company to terminate
the employee's employment at any time or increase or decrease the employee's
compensation from the rate in existence at the time of granting of an Award.

     The maximum number of shares of Capital Stock with respect to which Stock
Options may be granted to any one Participant under the Plan during any calendar
year is 1,000,000 shares.

     The Board may, at or prior to the time of grant, designate any Award as a
Qualified Performance-Based Award, in which event it shall take such action with
respect to such Award and the terms thereof (including the imposition of
additional requirements not otherwise required by the terms of the Plan), and
the provisions of the Plan or any Award Agreement shall be construed or deemed
amended, as shall be necessary to cause such Award to qualify for the Section
162(m) Exemption.

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     8.   STOCK OPTION EXERCISE.

     The price at which shares of Capital Stock may be purchased under a Stock
Option shall be paid in full at the time of the exercise in cash.

     9.   AWARDS - CERTAIN RIGHTS AND OBLIGATIONS.

     Awards and all other benefits under the Plan (including Stock Option
Shares) shall include and be subject to such obligations and rights as may be
set forth in or pursuant to the related Award Agreement including, without
limitation, registration rights, tag-along rights, drag-along rights and
restrictions on transfer.

     10.  TAXES.

     The Company shall have the right to deduct applicable taxes from any Award
payment and withhold, at the time of delivery or vesting of shares under the
Plan, an appropriate number of shares for payment of taxes required by law, to
require a Participant to pay to the Company in cash any amounts required to be
withheld or to take such other action as may be necessary in the opinion of the
Company to satisfy all obligations for withholding of such taxes.

     11.  CHANGES TO THE PLAN AND AWARDS.

     (a)  Changes to the Plan.  The Board may amend, alter, suspend, discontinue
or terminate the Plan without the consent of shareholders or Participants,
except as is required by any federal or state law or regulation or the rules of
any stock exchange on which the Capital Stock may be listed, or if the Board in
its discretion determines that obtaining such shareholder approval is for any
reason advisable; provided, however, that, without the consent of an affected
Participant, no amendment, alteration, suspension, discontinuation or
termination of the Plan may impair the rights of such Participant under any
Award theretofore granted to such Participant.

     (b)  Changes to Awards. The Board may waive any conditions or rights under,
or amend, alter, accelerate, suspend, discontinue or terminate, any Award
theretofore granted and any Award Agreement relating thereto; provided, however,
that, without the consent of an affected Participant, no such amendment,
alteration, suspension, discontinuation or termination of any Award may impair
the rights of such Participant under such Award.

     12.  TERMINATION OF EMPLOYMENT.

     If the employment of a Participant by the Company terminates, all Awards
and other benefits under the Plan (including Stock Option Shares) held by such
Participant shall be governed by, and shall be subject to, the terms and
conditions set forth below.

     (a)  Death or Disability.

          (i)  If the employment of any Participant is terminated as a result of
death or Disability, all Stock Options held by such Participant (A) which are
not then exercisable shall terminate and (B) which are then exercisable shall
terminate at the close of business in St. Louis, Missouri on the date which is
the first anniversary of such Participant's termination of employment.  In
addition, the Company shall have the right to purchase (A) from time to time so
long as they are exercisable, all or any portion of such exercisable Stock
Options at a price equal to the Net Stock Option Value of the shares of Capital
Stock subject to such Stock Options on the purchase date and (B) any or all of
the Stock Option Shares held by such Participant at a price per share equal to
their Fair Market Value.

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          (ii)   In the event of a Participant's death, any remaining rights
with respect to any outstanding Award shall be exercised by the Participant's
estate or beneficiaries under such terms as may be specified in the applicable
Award Agreement. Any such remaining rights to outstanding Awards shall pass by
will or the laws of descent and distribution in the following order: (A) to
beneficiaries so designated by the Participant; if none, then (B) to a legal
representative of the Participant; if none, then (C) to the persons entitled
thereto as determined by a court of competent jurisdiction. Subject to
subparagraph (iv) below, Awards so passing shall be exercised or paid out at
such times and in such manner as if the Participant were living.

          (iii)  In the event a Participant is deemed by the Company to be
Disabled, Awards and rights to any such Awards which are payable or exercisable
may be paid to or exercised by the Participant, if legally competent, or a
conservator or other legally designated agent or representative if the
Participant is legally incompetent by virtue of such Disability.

          (iv)   After the death or Disability of a Participant, the Board may
in its sole discretion at any time (A) terminate restrictions in Award
Agreements, (B) accelerate any or all installments and rights, and (C) instruct
the Company to pay the total of any accelerated payments in a lump sum to the
Participant, the Participant's estate, beneficiaries or representative -
notwithstanding that, in the absence of such termination of restrictions or
acceleration of payments, any or all of the payments due under the Awards might
ultimately have become payable to other beneficiaries.

     (b)  Cause.

          (i)    If the employment of any Participant is terminated for Cause,
all Stock Options held by such Participant shall terminate. In addition, the
Company shall have the right to purchase, from time to time for a period of 30
days following such termination, any or all of the Stock Option Shares held by
such Participant at a price per share equal to the lower of its cost (the
exercise price) or its Fair Market Value. For purposes of the foregoing, "Cause"
shall have the same meaning as in the Participant's written employment agreement
with the Company or, if the Participant has not entered into a written
employment agreement, shall mean (A) gross neglect of or wilful and continuing
refusal to substantially perform the Participant's duties (other than due to
death or Disability), (B) breach of any material policy of the Company
(including, without limitation, any policy regarding confidentiality), (C)
willfully engaging in conduct which is demonstrably injurious to Blackstone or
the Company, or (D) commission of or the entering of a plea of guilty or nolo
contendere to (1) a felony or (2) a misdemeanor involving moral turpitude.

          (ii)   Termination of a Participant for Cause shall be effected by a
majority vote of the Board at a meeting at which such Participant (and such
Participant's counsel) shall have had the opportunity to be heard, provided that
such Participant shall have received written notice of such termination at least
30 days prior to such meeting and such Participant shall have failed to cure
such Cause (if curable) within 15 days of such notice to the reasonable
satisfaction of the Board.

The foregoing provisions of this subsection (b) are applicable solely for
purposes of the Plan and shall not affect in any way the right of the Company to
terminate any employee or (except regarding the Plan) the consequences thereof.

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     (c)  Other Termination.

          (i)  If the employment of any Participant is terminated for any reason
other than death or Disability or Cause, as described in subsections (a) and (b)
above, all Stock Options held by such Participant (A) which are not then
exercisable shall terminate and (B) which are then exercisable shall terminate
at the close of business in St. Louis, Missouri on the date which is 90 days
after such Participant's termination of employment.  In addition, the Company
shall have the right to purchase (A) from time to time so long as they are
exercisable, all or any portion of such exercisable Stock Options at a price
equal to the Net Stock Option Value of the shares subject to such Stock Options
on the purchase date and (B) any or all of the Stock Option Shares held by such
Participant at a price per share equal to their Fair Market Value.

          The right of the Company to purchase exercisable Stock Options and
Stock Option Shares pursuant to this Section 12 shall be exercisable upon 30
days written notice to the Participant specifying the purchase date.

          Any provision of the Plan to the contrary notwithstanding, the Company
shall not have the right to purchase any exercisable Stock Options or Stock
Option Shares pursuant to this Section 12 following the establishment (in the
reasonable judgment of the Board) of a public market for the Capital Stock.

          In the event of uncertainty as to interpretation of or controversies
concerning this Section 12, the Board's determinations shall be binding and
conclusive.

     13.  CANCELLATION AND RESCISSION OF AWARDS.

     Unless the Award Agreement specifies otherwise, the Board may cancel any
unexpired, unpaid or deferred Awards at any time if the Participant is not in
compliance with all other applicable provisions of the Award Agreement, the Plan
and with the following conditions:

     (a)  A Participant shall not render services for any organization or engage
directly or indirectly in any business which, in the judgment of the Chief
Executive Officer of the Company or other senior officer designated by the
Board, is or becomes competitive with the Company, or which organization or
business, or the rendering of services to such organization or business, is or
becomes otherwise prejudicial to or in conflict with the interests of the
Company.  For a Participant whose employment has terminated, the judgment of the
Chief Executive Officer shall be based on the Participant's position and
responsibilities while employed by the Company, the Participant's post-
employment responsibilities and position with the other organization or
business, the extent of past, current and potential competition or conflict
between the Company and the other organization or business, the effect on the
Company's customers, suppliers and competitors of the Participant's assuming the
post-employment position, and such other considerations as are deemed relevant
given the applicable facts and circumstances.  A Participant who has retired
shall be free, however, to purchase, as an investment or otherwise, stock or
other securities of such organization or business so long as they are listed
upon a recognized securities exchange or traded over-the-counter, and such
investment does not represent a substantial investment to the Participant or a
greater than 5% equity interest in the organization or business.

     (b)  A Participant shall not, without prior written authorization from the
Company, disclose to anyone outside the Company, or use in other than the
Company's business, any confidential information or material relating to the
business of the Company, acquired by the Participant either during or after
employment with the Company.

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     (c)  Failure to comply with the provisions of paragraph (a) or (b) of this
Section 13 prior to or during the six months after any exercise, payment or
delivery pursuant to an Award shall cause such exercise, payment or delivery to
be rescinded.  The Company shall notify the Participant in writing of any such
rescission within two years after such exercise, payment or delivery.  Within
ten days after receiving such a notice from the Company, the Participant shall
pay to the Company the amount of any gain realized or payment received as a
result of the rescinded exercise, payment or delivery pursuant to an Award.
Such payment shall be made either in cash or by returning to the Company the
number of shares of Capital Stock that the Participant received in connection
with the rescinded exercise, payment or delivery.

     14.  NONASSIGNABILITY.

          Unless otherwise provided by the Board, no Award or any other benefit
under the Plan (including Stock Option Shares) shall be assignable or
transferable, or payable to or exercisable by anyone other than the Participant
to whom it was granted , except (a) pursuant to subparagraph (a) of Section 12
and (b) that Stock Option Shares shall be assignable and transferrable subject
to such limitations and conditions as may be set forth in a stockholder or
similar agreement entered into in connection therewith.

     15.  MERGERS, REORGANIZATIONS AND OTHER CORPORATE TRANSACTIONS; CHANGE IN
          CONTROL.

     (a)  General.  In the event of any change in the outstanding Capital Stock
by reason of any stock dividend or split, reorganization, recapitalization,
merger, consolidation, spin-off, combination or exchange of Capital Stock or
other corporate exchange, or any distribution to shareholders of Capital Stock
other than regular cash dividends, the Board in its sole discretion and without
liability to any person may make such substitutions or adjustments, if any, as
it deems to be equitable, as to (i) the number or kind of Capital Stock or other
securities issued or reserved for issuance pursuant to the Plan or pursuant to
outstanding Awards, (ii) the Stock Option price and/or (iii) any other affected
terms of such Awards.

     (b)  Change in Control.  Except as may otherwise be provided in the related
Award Agreement, in the event of a Change in Control, the Board in its sole
discretion and without liability to any person may take such actions, if any, as
it deems necessary or desirable with respect to any Award (including, without
limitation, (i) the acceleration of an Award, (ii) the payment of a cash amount
in exchange for the cancellation of an Award and/or (iii) the requiring of the
issuance of substitute Awards that will substantially preserve the value, rights
and benefits of any affected Awards previously granted under the Plan) as of the
date of the consummation of the Change in Control.

     (c)  Pooling of Interest Accounting.  Notwithstanding the foregoing, in the
event that the implementation of any provision of the Plan would cause a Change
in Control transaction that was intended to be eligible for pooling-of-interests
accounting not to be so eligible, the Board may take any steps that it deems
necessary to preserve pooling treatment.

     16.  NOTICE.

     Any notice to the Company required by any of the provisions of the Plan
shall be addressed to the Legal Department of Clark Holdings in writing, and
shall become effective when it is received.

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     17.  LEGAL REQUIREMENTS.

     (a)  General.  The Plan, the granting and exercising of Awards thereunder
and the other obligations of the Company under the Plan shall be subject to all
applicable federal and state laws, rules and regulations and to such approvals
by any regulatory or governmental agency as may be required.  The Company, in
its discretion, may postpone the granting and exercising of Awards, the issuance
or delivery of Capital Stock under any Award or any other action permitted under
the Plan to permit the Company, with reasonable diligence, to complete such
stock exchange listing or registration or qualification of such Capital Stock or
other required action under any federal or state law, rule or regulation and may
require any Participant to make such representations and furnish such
information as it may consider appropriate in connection with the issuance or
delivery of Capital Stock in compliance with applicable laws, rules and
regulations.  The Company shall not be obligated by virtue of any provision of
the Plan to recognize the exercise of any Award or to otherwise sell or issue
Capital Stock in violation of any such laws, rules, or regulations; and any
postponement of the exercise or settlement of any Award under this provision
shall not extend the term of such Award, and neither the Company nor its
directors or officers shall have any obligation or liability to the Participant
with respect to any Award (or stock issuable thereunder) that shall lapse
because of such postponement.

     (b)  Rule 16b-3.  It is the intent of the Company that any Award granted to
a person who is subject to Section 16 of the 1934 Act qualify for exemption
under Rule 16b-3.  Accordingly (i) if any provision of the Plan or any Award
Agreement would cause such an Award to fail to qualify for such exemption, such
provision shall be construed or deemed amended to the extent necessary to enable
such Award to qualify for such exemption, and (ii) any provision of the Plan
which is intended solely to cause an Award to qualify for exemption under Rule
16b-3 shall apply only to the extent that such Award would otherwise be subject
to such Rule.

     18.  GOVERNING LAW.

     The Plan and all determinations made and actions taken pursuant thereto, to
the extent not otherwise governed by the laws of the United States, shall be
governed by the laws of the State of Delaware and construed accordingly.

     19.  EFFECTIVE AND TERMINATION DATES.

     The Plan shall become effective on September 28, 1999; provided that the
Plan shall not become effective and no initial Awards shall be effective unless
and until Clark Holdings obtains the affirmative vote of more than seventy-five
percent of all shareholders who (a) are not receiving any initial Awards or (b)
are not lineally related to, or the spouse of, any individual who would receive
the initial Awards.  The Board shall have the authority to grant Awards prior to
such approval; provided that the effectiveness of such Awards shall be subject
to such shareholder approval of the Plan.  The Plan shall terminate ten years
after its effective date, subject to earlier termination by the Board pursuant
to Section 11, after which no Awards may be made under the Plan, but any such
termination shall not affect Awards then outstanding or the authority of the
Board to continue to administer the Plan.
<PAGE>

                         CLARK REFINING HOLDINGS INC.
                    Stock Option Certificate And Agreement
                                (Time Vesting)


Name of Optionee: ((Name))                   Date of Option: ((Date))

Number of Shares: ((Shares))                 Option Price: $9.90 per Share


     CLARK REFINING HOLDINGS INC., a Delaware Corporation ("Clark Holdings"),
hereby enters into this Stock Option Certificate and Agreement with the optionee
named above (the "Optionee") under the Clark Refining Holdings Inc. 1999 Stock
Incentive Plan (the "Plan").

     SECTION 1.  GRANT.  Pursuant to authorization of the Board of Directors of
Clark Holdings (the "Board") under the Plan, Clark Holdings hereby grants to the
Optionee the right and option (the "Option") to purchase all or any part of the
number of shares of its Common Stock, $.01 par value per share (the "Capital
Stock"), set forth above on the terms and conditions set forth herein.

     SECTION 2.  TERM AND VESTING.  The Option is exercisable, to the extent
vested, in full or in part at any time prior to expiration.  The Option shall
expire in full to the extent not exercised on September 30, 2008.  The Option
shall vest as to the shares of Capital Stock covered by the Option as follows:
50% on the Date of Option and 25% on each January 1 thereafter, so that the
Option share be fully vested on January 1, 2001.

     SECTION 3.  DATE OF GRANT.  The Option was granted by the Board on the Date
of Option set forth above.

     SECTION 4.  PURCHASE PRICE.  The purchase price per share of the shares of
Capital Stock covered by the Option shall be the Option Price set forth above.

     SECTION 5.  RIGHT TO EXERCISE.  The Optionee may exercise the Option only
(a) if the Optionee is an employee of the Company (as defined in the Plan) on
the date of exercise (and it is otherwise then exercisable), or (b) if the
employment of the Optionee is terminated as a result of death or disability (and
the Option is otherwise exercisable on the date of termination), prior to the
date which is the first anniversary of the Optionee's termination of employment,
or (c) if the employment of the Optionee is terminated for any reason other than
death or disability or Cause (and the Option is otherwise exercisable on the
date of termination), prior to the date which is 90 days after the Optionee's
termination of employment.  If the employment of the Optionee is terminated for
Cause, the Option shall terminate.

     The Option shall not be affected by any change of duties or position of the
Optionee so long as the Optionee continues to be an employee of the Company.
Neither the Option nor this Agreement shall be deemed to confer upon the
Optionee any right to continue in the employment of the Company.
<PAGE>

     SECTION 6.   TERMINATION OF EMPLOYMENT.  If the employment of the Optionee
terminates, the Option and any Stock Option Shares acquired pursuant to the
Option shall be governed by, and shall be subject to, the terms and conditions
with respect to termination of employment set forth in the Plan.

     SECTION 7.   CERTAIN RIGHTS AND OBLIGATIONS.  The Option and any Stock
Option Shares acquired pursuant to the Option shall include and be subject to
such obligations and rights (including, without limitation,  registration
rights, tag-a-long rights, drag-a-long rights and restrictions on transfer) as
may be set forth in any stock or similar agreement entered into by the Company
and the Optionee with respect thereto.

     SECTION 8.   METHOD OF EXERCISE.  The Option may be exercised (in whole or
in part) by delivering to the Legal Department of Clark Holdings a written
notice of exercise signed by the Optionee (a) designating the number of shares
to be purchased and (b) either (i) accompanied by payment of the full amount of
the purchase price of the shares of Capital Stock with respect to which the
Option is exercised or (ii) specifying a date (not less than 5 nor more than 10
business days after the date of such notice) for the payment of such purchase
price.  The date of delivery of such notice of exercise shall be the date the
written notice is actually received by the Legal Department.  The purchase price
of shares of Capital Stock purchased under the Option (together with any
applicable withholding taxes) shall be paid in cash.

     SECTION 9.   MERGERS, REORGANIZATIONS AND OTHER CORPORATE TRANSACTIONS;
CHANGE IN CONTROL.  In the event of (a) any change in the outstanding Capital
Stock by reason of any stock dividend or split, reorganization,
recapitalization, merger, consolidation, spin-off, combination or exchange of
Stock or other corporate exchange, or any distribution to shareholders of
Capital Stock other than regular cash dividends, the Board may make certain
substitutions or adjustments, if any, as it deems to be equitable with respect
to the Plan or any Award or (b) a Change in Control, the Board may take such
actions, if any, as it deems necessary or desirable with respect to any Award,
all as provided in the Plan.  Such substitutions, adjustments or actions may be
made or taken by the Board in its sole discretion and without liability to any
person.

     SECTION 10.  CHANGE IN CONTROL.  In the event of a Change in Control, the
Option shall become exercisable in full.

     SECTION 11.  CANCELLATION AND RESCISSION.  The Board may cancel any
unexercised portion of the Option at any time if the Optionee is not in
compliance with this Agreement and the Plan, [including certain conditions
specified in the Plan relating to (a) activities which are competitive with the
Company or prejudicial to or in conflict with the interests of the Company or
(b) the unauthorized disclosure of confidential information relating to the
Company.  In addition, failure to comply with such conditions prior to or during
the six months after any delivery of Capital Stock pursuant to the Option shall
cause such delivery to be rescinded, as provided in the Plan.

     SECTION 12.  LEGAL REQUIREMENTS.  The Optionee agrees to make such
representations, furnish such information and take such other action as the
Board may consider necessary or appropriate in connection with the granting of
the Option and the issuance and delivery of Capital Stock pursuant thereto in
compliance with applicable laws, rules and regulations.  Such action may
include, without limitation, the representation and agreement by the Optionee
that the Optionee is acquiring such Capital Stock for the Optionee's own account
for investment and not with a view to the resale or other distribution of such
Capital Stock.

     SECTION 13.  LIMITATION OF RIGHTS.  The Optionee shall have none of the
rights of a shareholder with respect to shares of Capital Stock covered by the
Option until shares are issued to the Optionee upon exercise of the Option.
<PAGE>

     SECTION 14.  NON-ASSIGNABILITY.  Unless otherwise provided by the Board,
the Option and any Stock Option Shares acquired pursuant to the Option shall not
be assignable or transferable by the Optionee (voluntarily or involuntarily, by
operation of law or otherwise) and the Option may be exercised only by the
Optionee, except (a) as otherwise provided in the Plan in the event of the
Optionee's death or disability and (b) that the Stock Option Shares may be
assigned or transferred subject to such limitations and conditions as may be set
forth in a stockholder or similar agreement entered into in connection
therewith.

     SECTION 15.  INTERPRETATION.  It is intended that the Option shall be
subject to and governed by the provisions of the Plan.  The Option shall be so
interpreted and construed as to be consistent with such intention.  Terms
capitalized in this Stock Option Certificate and Agreement shall have the
meanings given to them in the Plan unless otherwise defined herein or some other
meaning is clearly indicated.  The Optionee represents that the Optionee has
received and reviewed a copy of the Plan.

     SECTION 16.  STOCKHOLDER AGREEMENT.  The exercise of the Option shall be
subject to the execution and delivery by the Optionee of a Stockholder Agreement
in substantially the form attached as Appendix I hereto, and the Optionee hereby
agrees to execute and deliver such Agreement prior to such exercise and to
comply with the terms thereof.

     SECTION 17.  OPTIONS UNDER 1995 PLAN.  If the Optionee is a participant in
the Clark USA, Inc. 1995 Long-Term Performance Plan, as a condition to the grant
of the Option the Optionee has surrendered to Clark Holdings for cancellation
stock option(s) granted (or the right to receive stock options) under such Plan
covering an aggregate of ((NumberofShares)) shares of Capital Stock of Clark USA
(constituting all of such option(s) granted to the Optionee or which the
Optionee may have the right to receive), which cancellation is hereby confirmed.

     SECTION 18.  COMPLETE AGREEMENT.  This Stock Option Certificate and
Agreement, together with the Plan and any related Stockholder Agreement,
constitute the entire agreement of the parties with regard to the subject matter
hereof, and contain all the covenants, promises and agreements between the
parties with respect to the treatment of all time vesting Stock Options and
Stock Option shares held by the Optionee and supersede all prior option
agreements and any other agreements which may contain provisions pertaining to
Stock Options and Stock Option Shares held by the Optionee.

     IN WITNESS WHEREOF, the parties hereto have executed this Stock Option
Certificate and Agreement as of _________________, the date of grant of the
Option.


OPTIONEE                          CLARK REFINING HOLDINGS INC.

___________________________       By:  ______________________

Printed Name: ________________    Its: ______________________

Social Security No.: _________
<PAGE>

                         CLARK REFINING HOLDINGS INC.

                    Stock Option Certificate And Agreement
                             (Performance Vesting)


Name of Optionee: ((Name))             Date of Option: ((Date))

Number of Shares: ((Shares))           Option Price: $9.90 per Share


     CLARK REFINING HOLDINGS INC., a Delaware Corporation ("Clark Holdings"),
hereby enters into this Stock Option Certificate and Agreement with the optionee
named above (the "Optionee") under the Clark Refining Holdings Inc. 1999 Stock
Incentive Plan (the "Plan").

     SECTION 1.  GRANT.  Pursuant to authorization of the Board of Directors of
Clark Holdings (the "Board") under the Plan, Clark Holdings hereby grants to the
Optionee the right and option (the "Option") to purchase all or any part of the
number of shares of its Common Stock, $.01 par value per share (the "Capital
Stock"), set forth above on the terms and conditions set forth herein.

     SECTION 2.  TERM AND VESTING.  The Option is exercisable, to the extent
vested, in full or in part at any time prior to expiration.  The Option shall
expire in full to the extent not exercised on September 30, 2008.  The Option
shall vest as to the shares of Capital Stock covered by the Option as follows:
The Option shall be exercisable on and after the seventh anniversary of the Date
of Option; provided, however, that following any Public Offering or upon a
Change in Control the Option shall be accelerated and may be exercised in
advance of such anniversary date upon the achievement of certain per share
prices of the Capital Stock, in accordance with the schedule set forth below.
For purposes of such schedule, "Change in Control Price" means the highest price
per share received by any holder of Capital Stock from the purchaser(s) in a
transaction or series of transactions that result in a Change in Control.

            Average Closing Price Per
                   Share of                         % of Shares With
              Capital Stock for Any                    Respect to
          180 Consecutive Days; or                     Which Option
           Change in Control Price                   is Exercisable
          ---------------------------               ----------------

                 Below $12.00                                0%

               $12.00 - $14.99                              10%

               $15.00 - $17.99                              20%

               $18.00 - $19.99                              30%

               $20.00 - $24.99                              50%

               $25.00 - $29.99                              75%

                 Above $29.99                              100%
<PAGE>

     SECTION 3.  DATE OF GRANT.  The Option was granted by the Board on the Date
of Option set forth above.

     SECTION 4.  PURCHASE PRICE.  The purchase price per share of the shares of
Capital Stock covered by the Option shall be the Option Price set forth above.

     SECTION 5.  RIGHT TO EXERCISE.  The Optionee may exercise the Option only
(a) if the Optionee is an employee of the Company (as defined in the Plan) on
the date of exercise (and it is otherwise then exercisable); or (b) if the
employment of the Optionee is terminated as a result of death or disability (and
the Option is otherwise exercisable on the date of termination), prior to the
date which is the first anniversary of the Optionee's termination of employment,
or (c) if the employment of the Optionee is terminated for any reason other than
death or disability or Cause (and the Option is otherwise exercisable on the
date of termination), prior to the date which is 90 days after the Optionee's
termination of employment.  If the employment of the Optionee is terminated for
Cause, the Option shall terminate.

     The Option shall not be affected by any change of duties or position of the
Optionee so long as the Optionee continues to be an employee of the Company.
Neither the Option nor this Agreement shall be deemed to confer upon the
Optionee any right to continue in the employment of the Company.

     SECTION 6.  TERMINATION OF EMPLOYMENT.  If the employment of the Optionee
terminates, the Option and any Stock Option Shares acquired pursuant to the
Option shall be governed by, and shall be subject to, the terms and conditions
with respect to termination of employment set forth in the Plan.

     SECTION 7.  CERTAIN RIGHTS AND OBLIGATIONS.  The Option and any Stock
Option Shares acquired pursuant to the Option shall include and be subject to
such obligations and rights (including, without limitation, registration rights,
tag-a-long rights, drag-a-long rights and restrictions on transfer) as may be
set forth in any stock or similar agreement entered into by the Company and the
Optionee with respect thereto.

     SECTION 8.  METHOD OF EXERCISE.  The Option may be exercised (in whole or
in part) by delivering to the Legal Department of Clark Holdings a written
notice of exercise signed by the Optionee (a) designating the number of shares
to be purchased and (b) either (i) accompanied by payment of the full amount of
the purchase price of the shares of Capital Stock with respect to which the
Option is exercised or (ii) specifying a date (not less than 5 nor more than 10
business days after the date of such notice) for the payment of such purchase
price.  The date of delivery of such notice of exercise shall be the date the
written notice is actually received by the Legal Department.  The purchase price
of shares of Capital Stock purchased under the Option (together with any
applicable withholding taxes) shall be paid in cash.

     SECTION 9.  MERGERS, REORGANIZATIONS AND OTHER CORPORATE TRANSACTIONS;
CHANGE IN CONTROL.  In the event of (a) any change in the outstanding Capital
Stock by reason of any stock dividend or split, reorganization,
recapitalization, merger, consolidation, spin-off, combination or exchange of
Stock or other corporate exchange, or any distribution to shareholders of
Capital Stock other than regular cash dividends, the Board may make certain
substitutions or adjustments, if any, as it deems to be equitable with respect
to the Plan or any Award or (b) a Change in Control, the Board may take such
actions, if any, as it deems necessary or desirable with respect to any Award,
all as provided in the Plan.  Such substitutions, adjustments or actions may be
made or taken by the Board in its sole discretion and without liability to any
person.
<PAGE>

     SECTION 10.  CANCELLATION AND RESCISSION.  The Board may cancel any
unexercised portion of the Option at any time if the Optionee is not in
compliance with this Agreement and the Plan, including certain conditions
specified in the Plan relating to (a) activities which are competitive with the
Company or prejudicial to or in conflict with the interests of the Company or
(b) the unauthorized disclosure of confidential information relating to the
Company.  In addition, failure to comply with such conditions prior to or during
the six months after any delivery of Capital Stock pursuant to the Option shall
cause such delivery to be rescinded, as provided in the Plan.

     SECTION 11.  LEGAL REQUIREMENTS.  The Optionee agrees to make such
representations, furnish such information and take such other action as the
Board may consider necessary or appropriate in connection with the granting of
the Option and the issuance and delivery of Capital Stock pursuant thereto in
compliance with applicable laws, rules and regulations.  Such action may
include, without limitation, the representation and agreement by the Optionee
that the Optionee is acquiring such Capital Stock for the Optionee's own account
for investment and not with a view to the resale or other distribution of such
Capital Stock.

     SECTION 12.  LIMITATION OF RIGHTS.  The Optionee shall have none of the
rights of a shareholder with respect to shares of Capital Stock covered by the
Option until shares are issued to the Optionee upon exercise of the Option.

     SECTION 13.  NON-ASSIGNABILITY.  Unless otherwise provided by the Board,
the Option and any Stock Option Shares acquired pursuant to the Option shall not
be assignable or transferable by the Optionee (voluntarily or involuntarily, by
operation of law or otherwise) and the Option may be exercised only by the
Optionee, except (a) as otherwise provided in the Plan in the event of the
Optionee's death or disability and (b) that the Stock Option Shares may be
assigned or transferred subject to such limitations and conditions as may be set
forth in a stockholder or similar agreement entered into in connection
therewith.

     SECTION 14.  INTERPRETATION.  It is intended that the Option shall be
subject to and governed by the provisions of the Plan.  The Option shall be so
interpreted and construed as to be consistent with such intention.  Terms
capitalized in this Stock Option Certificate and Agreement shall have the
meanings given to them in the Plan unless otherwise defined herein or some other
meaning is clearly indicated.  The Optionee represents that the Optionee has
received and reviewed a copy of the Plan.

     SECTION 15.  STOCKHOLDER AGREEMENT.  The exercise of the Option shall be
subject to the execution and delivery by the Optionee of a Stockholder Agreement
in substantially the form attached as Appendix I hereto, and the Optionee hereby
agrees to execute and deliver such Agreement prior to such exercise and to
comply with the terms thereof.

     SECTION 16.  OPTIONS UNDER 1995 PLAN.  No stock options granted under the
Clark USA, Inc. 1995 Long-Term Performance Plan have been surrendered or
canceled as a condition to, in exchange for or in consideration of the grant of
the Option.

     SECTION 17.  COMPLETE AGREEMENT.  This Stock Option Certificate and
Agreement, together with the Plan and any related Stockholder Agreement,
constitute the entire agreement of the parties with regard to the subject matter
hereof, and contain all the covenants, promises and agreements between the
parties with respect to the treatment of all performance vesting Stock Options
and Stock Option shares held by the Optionee and supersede all prior option
agreements and any other agreements which may contain provisions pertaining to
Stock Options and Stock Option shares held by the Optionee.
<PAGE>

     IN WITNESS WHEREOF, the parties hereto have executed this Stock Option
Certificate and Agreement as of ___________________________, the date of grant
of the Option.


OPTIONEE                                 CLARK REFINING HOLDINGS INC.


__________________________________      By: ________________________________

Printed Name: ____________________      Its:  ______________________________
Social Security No.: _____________
<PAGE>

                                                                      Appendix I

                             STOCKHOLDER AGREEMENT
                             ---------------------


          STOCKHOLDER AGREEMENT, dated as of __________, 1999 (the "Agreement"),
                                                                    ---------
among CLARK REFINING HOLDINGS INC., a Delaware corporation (the "Company" or
                                                                 -------
"Clark"), Blackstone Capital Partners III Merchant Banking Fund L.P., a Delaware
------
limited partnership (together with its affiliates, "Blackstone"); and
                                                    ----------
_____________, an individual ("Holder").
                               ------

          WHEREAS, as used in this Agreement, the term "Share" shall mean any
outstanding share of the common stock of the Company;

          WHEREAS, Blackstone holds a majority of the outstanding Shares; and

          WHEREAS, on the date hereof, Holder is acquiring Shares pursuant to
the Company's stock incentive plan;

          NOW, THEREFORE, in consideration of the mutual covenants and
conditions as hereinafter set forth, the parties hereto do hereby agree as
follows:


I.   REPRESENTATIONS AND WARRANTIES
     ------------------------------

          I.1  Representations and Warranties of the Company.  The Company
               ---------------------------------------------
represents and warrants to the Holder as follows:

          (a) the Company is a corporation duly incorporated, validly existing
and in good standing under the laws of the state of Delaware and has all
requisite corporate power and authority to execute and deliver this Agreement
and to perform its obligations hereunder.  The execution and delivery by the
Company of this Agreement, the performance by the Company of its obligations
hereunder, and the consummation by the Company of the transactions contemplated
hereby have been duly authorized by all requisite corporate action.  This
Agreement has been duly executed and delivered by the Company and, assuming the
due authorization, execution and delivery thereof by the Holder and Blackstone,
constitutes a legal, valid and binding obligation of the Company, enforceable
against the Company in accordance with its terms;

          (b) the execution, delivery and performance by the Company of this
Agreement and the consummation by the Company of the transactions contemplated
hereby do not and will not, with or without the giving of notice or the passage
of time or both, (i) violate the provisions of any law, rule or regulation
applicable to the Company or its assets, (ii) violate the provisions of the
certificate of incorporation or bylaws of the Company, as amended, or (iii)
violate any judgment, decree, order or award of any court, governmental or
quasi-governmental agency or arbitrator applicable to the Company or its assets;
and

          (c) no consent, approval, exemption or authorization is required to be
obtained from, no notice is required to be given to and no filing is required to
be obtained from any third party (including, without limitation, governmental
and quasi-governmental agencies, authorities and instrumentalities of competent
jurisdiction) by the Company, in order for this Agreement to constitute a legal,
valid and binding obligation of the Company.

          I.2  Representations and Warranties of the Holder.  The Holder
               --------------------------------------------
represents and warrants to the Company that:

          (a)  this Agreement has been duly executed and delivered by the Holder
and, assuming the due authorization, execution and delivery thereof by the
Company and Blackstone, constitutes a legal, valid and binding obligation of the
Holder, enforceable against the Holder in accordance with its terms;
<PAGE>

                                                                              17

          (b)  the execution, delivery and performance by the Holder of this
Agreement and the consummation by the Holder of the transactions contemplated
hereby do not and will not, with or without the giving of notice or the passage
of time or both, (i) violate the provisions of any law, rule or regulation
applicable to the Holder or its assets, or (ii) violate any judgment, decree,
order or award of any court, governmental or quasi-governmental agency or
arbitrator applicable to the Holder or its assets;

          (c)  no consent, approval, exemption or authorization is required to
be obtained from, no notice is required to be given to, and no filing is
required to be obtained from, any third party (including, without limitation,
governmental and quasi-governmental agencies, authorities and instrumentalities
of competent jurisdiction) by the Holder in order for this Agreement to
constitute a legal, valid and binding obligation of the Holder;

          (d)  Holder is acquiring the Shares for investment solely for its own
account and not with a view to, or for resale in connection with, the
distribution or other disposition thereof;

          [(e) the Holder is an "accredited investor" within the meaning of
Rule 501 of Regulation D under the Securities Act of 1933, as amended, and the
rules and regulations promulgated thereunder, as the same may be amended from
time to time ("Securities Act");]*
               --------------

          [(f) the Holder's financial situation is such that it can afford to
bear the economic risk of holding the Shares for an indefinite period of time,
has adequate means for providing for its current needs and contingencies, and
can afford to suffer a complete loss of its investment in the Shares;]*

          [(g) the Holder's knowledge and experience in financial and business
matters are such that it is capable of evaluating the merits and risks of the
investment in the Shares;]*

          (h)  the Holder understands that the Shares are a speculative
investment which involves a high degree of risk of loss of Holder's investment
therein, there are substantial restrictions on the transferability of the
Shares, and, on the date hereof and for an indefinite period following the date
hereof, there will be no public market for the Shares and, accordingly, it may
not be possible for the Holder to liquidate its investment in case of emergency,
if at all;

          (i)  the Holder understands and has taken cognizance of all the risk
factors related to the purchase of the Shares, and, other than as set forth in
this Agreement, no representations or warranties have been made to the Holder or
its representatives concerning the Shares or the Company or their prospects or
other matters;

          (j)  the Holder has relied upon independent investigations made by it
and, to the extent believed by the Holder to be appropriate, its
representatives, including its own professional, financial, tax and other
advisors;

          (k)  the Holder has received information about the Company and been
given the opportunity to examine all documents and to ask questions of, and to
receive answers from, the Company and its representatives concerning the Company
and the terms and conditions of the purchase of the Shares and to obtain any
additional information which the Holder deems necessary; and

_____________________________
* If applicable to the Holder.
<PAGE>

                                                                              18

          (i)    all information which the Holder has provided to the Company
and its representatives concerning the Holder and its financial position is
complete and correct as of the date of this Agreement.

II.  TRANSFERS
     ---------

          II.1   Limitations on Transfer.  (a)  Holder hereby agrees that,
                 -----------------------
except for any transfer, sale, assignment, exchange, mortgage, pledge,
hypothecation or other disposition of any Shares or any interest therein
"Transfer") effected pursuant to an effective registration statement filed under
 --------
the Securities Act, no Transfer shall occur unless the Company has been
furnished with an opinion in form and substance reasonably satisfactory to the
Company of counsel reasonably satisfactory to the Company that such Transfer is
exempt from the provisions of Section 5 under the Securities Act.

          (b)    Holder hereby agrees that, except for Transfers in connection
with a sale of shares of Common Stock to the public pursuant to an effective
registration statement filed under the Securities Act ("Public Offering"),
                                                        ---------------
Transfers pursuant to Rule 144 (other than Rule 144(k)) under the Securities Act
and Transfers pursuant to Section 2.5 or 2.6, no Transfer shall occur unless the
transferee shall agree to become a party to, and be bound to the same extent as
its transferor by the terms of, Articles II and III of this Agreement.

          (c)    Notwithstanding anything contained herein to the contrary, but
subject to Section 2.2, Holder hereby agrees that, in addition to the limitation
on transfer set forth in Section 2.8(a), no Transfer shall occur until eighteen
months after the date of Clark's initial underwritten Public Offering or such
earlier date after such initial Public Offering on which an underwritten
registered secondary offering involving shares of Common Stock occurs.
Notwithstanding the foregoing, in the event Blackstone sells shares for its own
account in such initial Public Offering, Holder may transfer Shares in such
offering in accordance with Section 2.7 hereof, except that in such circumstance
clause (ii) of Section 2.7(b) shall be deemed to read as follows: (ii) second,
to the extent that the number of shares of Common Stock which are proposed to be
sold in such offering is less than the number of shares of Common Stock which
the Company has been advised can be sold in such offering without having the
adverse effect referred to above, the number of shares of Common Stock
Blackstone intends to dispose of in such offering shall have priority.

          II.2   Transfers to Affiliates.  Notwithstanding anything contained
                 -----------------------
herein to the contrary, Holder shall be entitled from time to time to Transfer
any or all of the Shares beneficially owned by Holder to Holder's spouse or
descendants, or to a trust in favor of Holder's spouse or descendants, or to any
other entity the owners of which consist exclusively of Holder, Holder's spouse,
Holder's descendants or such trusts ("Permitted Affiliate"), who, in each such
                                      -------------------
case, agree in a writing satisfactory in form and substance to the Company to
become a party to, and be bound to the same extent as its transferor by the
terms of, Articles II and III of this Agreement.

          II.3   Effect of Void Transfers.  In the event of any purported
                 ------------------------
Transfer of any shares of Common Stock in violation of the provisions of this
Agreement, such purported Transfer shall be void and of no effect and the
Company shall not give effect to such Transfer.

          II.4   Legend on Securities.  Each certificate representing shares of
                 --------------------
Common Stock issued to Holder shall bear the following legend on the face
thereof:

          "THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A
     STOCKHOLDER AGREEMENT BETWEEN CLARK REFINING HOLDINGS INC. (THE "COMPANY"),
     AND __________________, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF
     THE COMPANY.  NO TRANSFER, SALE, ASSIGNMENT, PLEDGE, HYPOTHECATION OR OTHER
     DISPOSITION OF THE SECURITIES
<PAGE>

                                                                              19

     REPRESENTED BY THIS CERTIFICATE MAY BE MADE EXCEPT IN ACCORDANCE WITH THE
     PROVISIONS OF SUCH STOCKHOLDER AGREEMENT AND (A) PURSUANT TO A REGISTRATION
     STATEMENT EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) IF
     THE COMPANY HAS BEEN FURNISHED WITH AN OPINION IN FORM AND SUBSTANCE
     REASONABLY SATISFACTORY TO THE COMPANY OF COUNSEL REASONABLY SATISFACTORY
     TO THE COMPANY THAT SUCH TRANSFER, SALE, ASSIGNMENT, PLEDGE, HYPOTHECATION
     OR OTHER DISPOSITION IS EXEMPT FROM THE PROVISIONS OF SECTION 5 OF THE
     SECURITIES ACT OF 1933, AS AMENDED, AND THE RULES AND REGULATIONS
     THEREUNDER. THE HOLDER OF THIS CERTIFICATE, BY ACCEPTANCE OF THIS
     CERTIFICATE, AGREES TO BE BOUND BY ALL OF THE PROVISIONS OF SUCH
     STOCKHOLDER AGREEMENT."

          II.5  Tag-Along Rights.  (a)  So long as this Agreement shall remain
                ----------------
in effect and Blackstone beneficially owns on a fully diluted basis an aggregate
number of shares of Common Stock not less than one-fourth (1/4) of the Common
Stock owned by Blackstone on the date hereof, with respect to any proposed
Transfer by Blackstone (in such capacity, a "Transferring Stockholder") of 25%
                                             ------------------------
or more of the shares of Common Stock held by Blackstone, other than a Transfer
(i) to any affiliate of Blackstone or any stockholder, partner or other equity
owner of any such affiliate or Blackstone or (ii) pursuant to a Public Offering,
the Transferring Stockholder shall have the obligation, and Holder and the
Permitted Affiliates shall have the right, to require the proposed transferee to
purchase from Holder and the Permitted Affiliates (in such capacity, a "Tagging
                                                                        -------
Stockholder") a number of the Shares up to the product (rounded up to the
-----------
nearest whole number) of (i) the quotient determined by dividing (A) the
aggregate number of Shares owned by Blackstone to be included in the
contemplated Transfer by (B) the aggregate number of Shares owned by Blackstone
immediately prior to the contemplated Transfer, and (ii) the total number of
Shares owned by the Tagging Stockholder, and at the same price per share of
Common Stock and upon the same terms and conditions (including without
limitation time of payment and form of consideration) applicable to the
Transferring Stockholder; provided, that in order to be entitled to exercise its
                          --------
right to sell shares of Common Stock to the proposed transferee pursuant to this
Section 2.5, the Tagging Stockholder must agree to make to the transferee the
same representations, warranties, covenants, indemnities and agreements that the
Transferring Stockholder agrees to make in connection with the proposed Transfer
of the shares of Common Stock of the Transferring Stockholder; and provided
                                                                   --------
further, that all representations and warranties shall be made by the Tagging
-------
Stockholder and the Transferring Stockholder severally and not jointly and that
the liability of the Transferring Stockholder and the Tagging Stockholder
(whether pursuant to a representation, warranty, covenant, indemnification
provision or agreement) for liabilities in respect of the Company shall be
evidenced in writings executed by them and the transferee and shall be borne by
each of them on a pro rata basis.

          (b)   The Transferring Stockholder shall give notice to Holder of each
proposed Transfer giving rise to the rights of the Tagging Stockholder set forth
in the first sentence of Section 2.5(a) at least 15 business days prior to the
proposed consummation of such Transfer, setting forth the number of shares of
Common Stock proposed to be so transferred, the name and address of the proposed
transferee, the proposed amount and form of consideration and the other terms
and conditions offered by the proposed transferee, and a representation that the
proposed transferee has been informed of the tag-along rights provided for in
this Section 2.5 and has agreed to purchase shares of Common Stock in accordance
with the terms hereof.  The tag-along rights provided by this Section 2.5 must
be exercised by the Tagging Stockholder within 5 business days following receipt
of the notice required by the preceding sentence, by delivery of a written
notice to the Transferring Stockholder indicating such Tagging Stockholder's
desire to exercise its rights and specifying the number of shares of Common
Stock it desires to sell.
<PAGE>

                                                                              20

          (c)   If the Tagging Stockholder exercises its rights under Section
2.5(a), the closing of the purchase of Shares with respect to which such rights
have been exercised shall take place concurrently with the closing of the sale
of the Transferring Stockholder's Shares.

          II.6  Drag-Along Rights.  So long as this Agreement shall remain in
                -----------------
effect and Blackstone beneficially owns on a fully diluted basis an aggregate
number of shares of Common Stock not less than one-fourth (1/4) of the Common
Stock owned by Blackstone on the date hereof, if Blackstone receives an offer
from a person other than Holder or any of its affiliates (a "Third Party") to
                                                             -----------
purchase 25% or more  of the shares of Common Stock owned by Blackstone and such
offer is accepted by Blackstone, then Holder hereby agrees that it will Transfer
the Applicable Number  (as defined below) of Shares owned by it to such Third
Party upon the terms and conditions of the offer (including without limitation
time of payment and form of consideration) applicable to Blackstone, provided
                                                                     --------
that Holder must agree to make to the Third Party the same representations,
warranties, covenants, indemnities and agreements that Blackstone agrees to make
in connection with the proposed Transfer; and provided further, that all
                                              -------- -------
representations and warranties shall be made by Holder and Blackstone severally
and not jointly and that the liability of Holder and Blackstone (whether
pursuant to a representation, warranty, covenant, indemnification provision or
agreement) for liabilities in respect of the Company shall be evidenced in
writings executed by them and the Third Party and shall be borne by each of them
on a pro rata basis.  The "Applicable Number" shall mean a number (rounded up to
the nearest whole number) equal to the product of (i) the quotient determined by
dividing (A) the aggregate number of shares owned by Blackstone to be included
in the contemplated Transfer by (B) the aggregate number of shares owned by
Blackstone immediately prior to the contemplated Transfer, and (ii) the total
number of shares owned by Holder.

          II.7  Piggyback Rights.  (a)  Each time the Company is planning to
                ----------------
file a registration statement under the Securities Act in connection with the
proposed offer and sale of Common Stock by the Company and/or Blackstone (other
than under Form S-8 or Form S-4 or a similar successor form), the Company will
give prompt written notice thereof to Holder regarding Holder's rights under
this Section 2.7, at least 15 business days prior to the anticipated filing date
of such registration statement; provided, that Holder and its affiliates shall
                                --------
have no rights pursuant to this Section 2.7 with respect to the first Public
Offering of Common Stock if the Company is the only person including shares of
Common Stock in such registration statement.  Upon the written request of Holder
or the Permitted Affiliates made within 5 business days after the receipt of any
such notice from the Company, which request shall specify the number of Shares
(the "Holder Piggy-Back Shares") intended to be disposed of by Holder or the
      ------------------------
Permitted Affiliates in such offering, the Company will use its reasonable
efforts to effect the registration under the Securities Act of all Holder Piggy-
Back Shares which the Company has been so requested to register by Holder, to
the extent required to permit the disposition of the Holder Piggy-Back Shares to
be registered; provided, that (i) if, at any time after giving written notice of
               --------
its intention to register any Common Stock and prior to the effective date of
the registration statement filed in connection with such registration, the
Company or Blackstone shall determine for any reason not to proceed with the
proposed registration, the Company may at its election give written notice of
such determination to the holder of Holder Piggy-Back Shares and thereupon shall
be relieved of its obligation to register any Holder Piggy-Back Shares in
connection with such registration and (ii) if such registration involves an
underwritten offering, the holder of Holder Piggy-Back Shares requesting to be
included in the registration must sell its shares to the underwriters on the
same terms and conditions as apply to the Company and/or Blackstone.

          (b)   If a registration pursuant to this Section 2.7 involves an
underwritten offering and the managing underwriter or underwriters in good faith
advise the Company in writing that, in their opinion, the number of shares of
Common Stock which the Company, Blackstone and the holder of Holder Piggy-Back
Shares intend to include in such registration exceeds the number of shares of
Common Stock which can be sold in such offering without having an adverse effect
on such offering (including the price at which the shares of Common Stock can be
sold), then the Company will include in such registration (i) first, 100% of the
shares the Company proposes to sell for its own account, if any, and 100% of the
shares of
<PAGE>

                                                                              21

any person exercising demand registration rights (other than Blackstone), if
any, and (ii) second, to the extent that the number of shares described under
clause (i) is less than the number of shares of Common Stock which the Company
has been advised can be sold in such offering without having the adverse effect
referred to above, the number of shares Blackstone intends to dispose of in such
offering, the Holder Piggy-Back Shares and shares of any other person exercising
similar piggy-back registration rights, on a pro rata basis.

          II.8  Other Registration-Related Matters.
                ----------------------------------

          (a)   Holder agrees that it shall not effect any direct or indirect
Transfer of Com mon Stock during the 14 days prior to or the 180 day period
beginning on the effective date of a registration statement (whether pursuant to
Section 2.7 or otherwise, except as part of such registration) if and to the
extent reasonably requested in writing by the managing underwriter of the
underwritten public offering.

          (b)   The Company agrees not to effect any direct or indirect Transfer
of Common Stock during the 14 days prior to and the 180 day period beginning on
the effective date of any registration statement in which Holder is
participating pursuant to Section 2.7 in connection with an underwritten public
offering of Common Stock, if and to the extent reasonably requested in writing
by the managing underwriter of the underwritten public offering.

          (c)   The Company may require any person that is selling shares of
Common Stock in a Public Offering to furnish to the Company such information
regarding such person and the distribution of the shares of Common Stock which
are included in a Public Offering as may from time to time reasonably be
requested in writing in order to comply with the Securities Act.

          2.9   Call Options.
                ------------

          (a)   If Holder's employment with the Company or its subsidiaries
terminates for any reason, the Company (or any of its assignees) shall have the
right and option to purchase, for a period of 30 days following the date of such
termination of employment of Holder, and Holder shall be required to sell to the
Company (or to any such assignee), any or all of the shares of Common Stock
(including any fractional shares) then owned by Holder, at a price per share
equal to the applicable purchase price determined pursuant to paragraph (c) of
this Section 2.9.

          (b)   If the Company desires to exercise its option to purchase any
shares pursuant to paragraph (a) of this Section 2.9, the Company shall, not
later than 30 days after the date of termination of employment, send written
notice to Holder of its intention to purchase shares, specifying the number of
shares to be purchased.  The closing of the purchase shall take place at the
principal office of the Company on a date specified by the Company no earlier
than the tenth and no later than the thirtieth day after the giving of such
notice.

          (c)   In the event of a purchase by the Company pursuant to paragraph
(a) of this Section 2.9, the purchase price shall be:

          (i)   if Holder's employment was terminated for Cause (as defined
     below), a price per share equal to the lower of (x) the price per share
     paid by Holder (as proportionately adjusted for all subsequent stock
     splits, stock dividends and other recapitalizations) and (y) Fair Market
     Value (as defined below); or

          (ii)  if Holder's employment was terminated for any other reason, Fair
     Market Value.

          (d)   For purposes of this Section 2.9:
<PAGE>

                                                                              22

          "Cause" shall have the meaning set forth in Holder's employment
agreement with the Company or its subsidiaries; or, if there is no employment
agreement or such employment agreement does not define the term "cause," shall
mean (i) gross neglect of or willful and continuing refusal substantially to
perform one's duties (other than due to disability), (ii) breach of any material
policy of the Company or, if Holder is employed by a subsidiary of the Company,
such subsidiary, (iii) willful engaging in conduct that is demonstrably
injurious to Blackstone, the Company or the Company's subsidiaries or affiliates
or (iv) commission or plea of guilty or nolo contendere to a felony or
misdemeanor involving moral turpitude; and

          "Fair Market Value" shall mean, with respect to shares of Common
Stock, the fair market value of such shares as determined from time to time by
the Company's board of directors in good faith.  Unless otherwise determined by
the Board, (a) if the Common Stock is traded on NASDAQ, the fair market value of
such shares as of any date shall be the closing date sale price on that date of
a share of Common Stock as reported in the NASDAQ National Market Issues
quotations of the Midwest Edition of the Wall Street Journal, or (b) if the
Common Stock is traded on the New York Stock Exchange, the Fair Market Value of
such shares as of any date shall be the closing sale price on that date of a
share of Common Stock as reported on the New York Stock Exchange Composite Tape
(or, if the Common Stock is not traded on NASDAQ or the New York Stock Exchange,
as applicable, on such date, on the next following date on which it is so
traded).


III.  OTHER
      -----

          III.1  Additional Securities Subject to Agreement.  Holder agrees that
                 ------------------------------------------
all shares of Common Stock which it shall hereafter acquire by means of a stock
split, stock dividend, distribution or otherwise (other than pursuant to a
Public Offering) shall be subject to the provisions of this Agreement to the
same extent as if held on the date hereof.

          III.2  Termination.  This Agreement shall terminate, and thereby
                 -----------
become null and void, in full on the earliest date on which Blackstone does not
beneficially own in the aggregate at least 5% of the Common Stock outstanding on
a fully diluted basis.

          III.3  Injunctive Relief.  Holder acknowledges and agrees that a
                 -----------------
violation of any of the terms of this Agreement will cause the Company and
Blackstone irreparable injury for which adequate remedy at law is not available.
Accordingly, it is agreed that the Company or Blackstone shall be entitled to an
injunction, restraining order or other equitable relief to prevent breaches of
the provisions of this Agreement and to enforce specifically the terms and
provisions hereof in any court of competent jurisdiction in the United States or
any state thereof, in addition to any other remedy to which they may be entitled
at law or equity.

          III.4  Other Stockholders' Agreements.  Holder shall not enter into
                 ------------------------------
any stockholder agreement or other arrangement of any kind with any person with
respect to shares of Common Stock, and Holder represents and warrants that it
has not previously entered into such an agreement that remains in full force and
effect as of the date hereof which is inconsistent with the provisions of this
Agreement or which may impair its ability to comply with this Agreement.

          III.5  Amendments.  This Agreement may be amended only by a written
                 ----------
instrument signed by each party hereto.

          III.6  Successors, Assigns and Transferees.  The provisions of this
                 -----------------------------------
Agreement shall be binding upon and shall inure to the benefit of the parties
hereto and their respective successors and transferees permitted hereunder
(except for transferees that are transferred Common Stock pursuant to a Public
Offering, pursuant to Rule 144 under the Securities Act or pursuant to Section
2.5 or 2.6), each of
<PAGE>

                                                                              23

which shall agree in writing to become a party hereto and be bound to the same
extent hereby as the transferor that has transferred the Common Stock to such
transferees; provided, that if Holder transfers a portion of its Common Stock to
             --------
one or more transferees which are entitled to rights of the transferor
hereunder, then such transferee(s) shall exercise such rights as a single group
with that transferor and its affiliates; provided further, that the rights
                                         ----------------
granted to the Holder in Sections 2.5 and 2.7 can only be transferred to
Permitted Affiliates.

          III.7  Notices.  All notices, requests and demands to or upon the
                 -------
respective parties hereto to be effective shall be in writing (including by
telecopy), and, unless otherwise expressly provided herein, shall be deemed to
have been duly given or made when delivered by hand, or two days after being
delivered to a recognized courier (whose stated terms of delivery are three days
or less to the destination of such notice) or, in the case of telecopy notice,
when received, addressed as follows to the parties hereto, or to such other
address as may be hereafter notified by the respective parties hereto:

                    When Holder is the intended recipient:

                         ___________________________
                         ___________________________
                         ___________________________
                         Attention: ________________
                         Telecopy:  ________________

                  When the Company is the intended recipient:

                         Clark Refining Holdings, Inc.
                         8182 Maryland Avenue
                         St. Louis, Missouri  63105
                         Attention: Maura J. Clark
                         Telecopy:  (314) 854-1570

          with a copy to:

                         Simpson Thacher & Bartlett
                         425 Lexington Avenue
                         New York, New York  10017
                         Attention: Wilson S. Neely
                         Telecopy:  (212) 455-2502

          III.8  Integration.  This Agreement, and the documents referred to
                 -----------
herein or delivered pursuant hereto, contain the entire understanding of the
parties with respect to the subject matter hereof.  There are no agreements,
representations, warranties, covenants or undertakings with respect to the
subject matter hereof other than those expressly set forth herein or in the
Company's stock incentive plan and any related award agreement.  If there is any
conflict between such incentive plan or such award agreement and this Agreement,
the provisions of this Agreement shall control. This Agreement supersedes all
other prior agreements and understandings between the parties with respect to
the matters set forth herein.

          III.9  Severability.  If one or more of the provisions, paragraphs,
                 ------------
words, clauses, phrases or sentences contained herein, or the application
thereof in any circumstances, is held invalid, illegal or unenforceable in any
respect for any reason, the validity, legality and enforceability of any such
provision, paragraph, word, clause, phrase or sentence in every other respect
and of the remaining provisions, paragraphs, words, clauses, phrases or
sentences hereof shall not be in any way impaired, it
<PAGE>

                                                                              24

being intended that all rights, powers and privileges of the parties hereto
shall be enforceable to the fullest extent permitted by law.

          III.10  Counterparts.  This Agreement may be executed in two or more
                  ------------
counterparts, and by different parties on separate counterparts, each of which
shall be deemed an original, but all of which shall constitute one and the same
instrument.

          III.11  Governing Law.  This Agreement shall be governed by and
                  -------------
construed and enforced in accordance with the laws of the State of New York
without regard to the conflicts of law principles thereof.  The parties
executing this Agreement hereby agree to submit to the non-exclusive
jurisdiction of the federal and state courts located in the State of New York in
any action or proceeding arising out of or relating to this Agreement.

          III.12  Voting.  Holder hereby agrees that, so long as this
                  ------
Agreement shall remain in effect, it will vote all of the Common Stock
beneficially owned or held of record by it to ratify, approve and adopt any and
all actions (including without limitation the election of directors) adopted or
approved by Blackstone.


          IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.


                         CLARK REFINING HOLDINGS INC.


                         By:___________________________
                            Name:
                            Title:


                         BLACKSTONE CAPITAL PARTNERS III
                            MERCHANT BANKING FUND L.P.

                            By:  Blackstone Management Associates III,  L.L.C.,
                                 its general partner


                            By:___________________________
<PAGE>

                                                                              25

      Name:
      Title:


__________________________
Name of Holder: