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                                                                   Exhibit 10.11
                                                                   -------------

                              EMPLOYMENT AGREEMENT


     EMPLOYMENT AGREEMENT (the "Agreement") dated February 26, 2001 by and
between The Premcor Refining Group Inc. (the "Company") and Ezra C. Hunt (the
"Executive").

     WHEREAS, the Company considers it essential to its best interests and the
best interests of its stockholders to foster the employment of Executive by the
Company during the term of this Agreement and Executive is willing to accept
Executive's employment on the terms hereinafter set forth in this Agreement;

     NOW, THEREFORE, in consideration of the premises and mutual covenants
herein and for other good and valuable consideration, the parties agree as
follows:

1.   Term of Employment; Executive Representation.
     --------------------------------------------

     a.   Employment Term. Subject to the provisions of Section 8 of this
     Agreement, Executive shall be employed by the Company for the three-year
     period commencing on February 26, 2001 and ending on February 25, 2004 (the
     "Employment Term") on the terms and subject to the conditions set forth in
     this Agreement. Notwithstanding the preceding sentence, commencing February
     26, 2004, and on each anniversary thereof thereafter (each anniversary, an
     "Extension Date"), the Employment Term shall be automatically extended for
     an additional one-year period, unless either party provides the other party
     hereto with 90 days' written notice prior to the next Extension Date that
     the Employment Term shall not be so extended. For the avoidance of doubt,
     the term "Employment Term" shall include any extension that becomes
     applicable pursuant to the preceding sentence.

     b.   Executive Representation. Executive hereby represents to the Company
     that the execution and delivery of this Agreement by Executive and the
     Company and the performance by Executive of the Executive's duties
     hereunder shall not constitute a breach of, or otherwise contravene, the
     terms of any employment agreement or other agreement or policy to which
     Executive is a party or otherwise bound.


2.   Position.
     --------

     a.   While employed hereunder, Executive shall serve as the Company's
     Executive Vice-President and Chief Financial Officer and as an Executive
     Vice-President of Premcor Inc. and Premcor USA Inc. However, nothing
     contained herein shall in any way restrict the ability of the Company to
     assign Executive, with his consent, to other positions of equivalent status
     within the Company. In such positions, Executive shall have such duties and
     authority as shall be determined from time to time by the Board of
     Directors of the Company (the "Board"), and the Executive shall report
     directly to the Chief Executive Officer of the Company. If requested, the
     Executive shall also serve as a
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     member of the Board or the boards of any affiliates of the Company without
     additional compensation.

     b.   While employed hereunder, Executive will devote Executive's full
     business time and best efforts to the performance of Executive's duties
     hereunder and will not engage in any other business, profession or
     occupation for compensation or otherwise which would conflict with the
     rendition of such services either directly or indirectly; provided that
     nothing herein shall preclude Executive, subject to the prior approval of
     the Chief Executive Officer, from accepting appointment to the board of
     directors or trustees of any business corporation or any charitable
     organization, provided in each case, and in the aggregate, that such
     activities do not interfere with the performance of Executive's duties
     hereunder or conflict with Section 9. Any compensation earned by Executive
     for serving in such director or trustee capacity shall be the sole and
     exclusive property of Executive.


3.   Base Salary. While employed hereunder, the Company shall pay Executive a
base salary (the "Base Salary") at the annual rate of $375,000, payable in
regular installments in accordance with the Company's usual payment practices.
Executive shall be entitled to such increases in Executive's Base Salary, if
any, as may be determined from time to time in the sole discretion of the Board,
and any such increased Base Salary shall be deemed to be Executive's "Base
Salary" for purposes of this Agreement.


4.   Bonuses.
     -------

     a.   Signing Bonus. As consideration for Executive's entering into this
     Agreement, the Company shall pay Executive a one-time signing bonus of
     $100,000, payable as soon as practicable after the date hereof.

     b.   Annual Bonus. With respect to each calendar year while employed
     hereunder, Executive shall be eligible to earn an annual bonus award
     pursuant to the Company's annual incentive plan (the "Annual Incentive
     Plan") in an amount to be determined at the sole discretion of the Board in
     consultation with the Chief Executive Officer. Executive's Annual Bonus
     Opportunity (as defined in the Annual Incentive Plan) shall be 150% of Base
     Salary and his Annual Target Bonus (as defined in the Annual Incentive
     Plan) shall be 100% of Base Salary. However, Executive's Annual Bonus
     Opportunity and Annual Target Bonus shall be subject to change based upon
     modifications made from time to time to the Annual Incentive Plan by the
     Company's management team, which team shall include the Executive,
     provided, however, that in any such modification of the Annual Incentive
     Plan Executive's Annual Bonus Opportunity and Annual Target Bonus shall be
     no less than that of other similarly situated officers of the Company,
     including any Executive Vice President thereof. Notwithstanding the
     foregoing, Executive shall be entitled to an annual bonus of at least
     $236,950 and $100,000 for calendar years 2000 and 2001, respectively.

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5.   Equity Arrangements. Executive shall be granted an option to purchase
120,000 shares of the common stock of Premcor Inc. (the "Common Stock") pursuant
to the terms of the Premcor Inc. 1999 Stock Incentive Plan (the "Stock Incentive
Plan"). The option shall have a per share exercise price of $9.90.

     The options for 60,000 shares shall vest ratably over the three years
following the date hereof (1/3 per year), and the options for the remaining
60,000 shares shall vest on the earlier of the seventh anniversary of the grant
date or upon the achievement of the share prices set forth below for the Common
Stock: (i) following an initial public offering, as an average closing price for
any 180 day consecutive period, or (ii) in a Change in Control:

               Per Share Price                             % Vested
               ---------------                             --------
               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%

     The specific terms of such grant shall be set forth in a separate option
agreement, and shall be subject to the terms of the Stock Incentive Plan.


6.   Employee Benefits.
     -----------------

     a.   Welfare and Pension Benefits. The Company shall provide Executive
     during the term of his employment hereunder with coverage under all
     employee pension and welfare benefit programs, plans and practices in
     accordance with the terms thereof, which the Company generally makes
     available to its senior executives; provided, however, that the Company
     shall reimburse Executive for the cost of COBRA continuation coverage
     (elected by Executive under his prior employer's group health plan) during
     the first 30 days of the Employment Term (after which time Executive will
     be eligible for coverage under the Company's medical plan pursuant to this
     Section 6(a)).

     b.   Vacation and Other Perquisites. Executive shall also be entitled to a
     minimum of four weeks of paid vacation in each calendar year and sick leave
     days in each calendar year as established under the Company's policies as
     in effect from time to time, which shall be taken at such times as are
     consistent with Executive's responsibilities hereunder. In addition, the
     Company shall reimburse Executive for the reasonable cost of financial and
     tax preparation and planning services listed on Exhibit A incurred by
     Executive during the calendar year 2001, upon presentation by Executive
     from time to time of appropriately itemized accounts of such expenditures.
     Such accounts shall be subject to approval by the Chief Executive Officer.

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7.   Business Expenses. Executive is authorized to incur reasonable expenses in
carrying out his duties and responsibilities under this Agreement, including,
without limitation, expenses for travel and similar items related to such duties
and responsibilities. The Company will reimburse Executive for all such expenses
upon presentation by Executive from time to time of appropriately itemized and
approved (consistent with the Company's policy) accounts of such expenditures.


8.   Termination. The Executive's employment hereunder may be terminated by
either party at any time and for any reason; provided that Executive will be
required to give the Company at least 60 days advance written notice of any
resignation of Executive's employment. Notwithstanding any other provision of
this Agreement, the provisions of this Section 8 shall exclusively govern
Executive's rights upon termination of employment with the Company and its
affiliates. Upon termination of Executive's employment for any reason, Executive
agrees to resign, as of the date of such termination, from the Board and the
board of directors of any of the Company's affiliates.

     a.   By the Company For Cause or by Executive Resignation Without Good
Reason.

          (i)  Executive's employment hereunder may be terminated by the Company
          for Cause (as defined below) at any time or, upon 60 days prior
          written notice, by Executive without Good Reason (as defined below).

          (ii)  For purposes of this Agreement, "Cause" shall mean (A)
          Executive's continued failure to substantially perform Executive's
          duties hereunder (other than as a result of total or partial
          incapacity due to physical or mental illness) for a period of 30 days
          following written notice by the Company to Executive of such failure,
          (B) dishonesty in the performance of Executive's duties hereunder, (C)
          an act or acts on Executive's part constituting a felony under the
          laws of Missouri, (D) Executive's willful malfeasance or willful
          misconduct in connection with Executive's duties hereunder or any act
          or omission which is materially injurious to the financial condition
          or business reputation of the Company or any of its subsidiaries or
          affiliates, or (E) Executive's breach of the restrictive covenants set
          forth in Section 9 hereof.

          (iii)  If Executive's employment is terminated by the Company for
          Cause or by Executive without Good Reason, Executive shall be entitled
          to receive:

               (A)  the Base Salary through the date of termination;

               (B)  any annual bonus earned but unpaid as of the date of
               termination for any previously completed calendar year;

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               (C)  reimbursement for any unreimbursed business expenses
               properly incurred by Executive in accordance with Company policy
               prior to the date of Executive's termination; and

               (D)  such employee benefits, if any, as to which Executive may be
               entitled under the employee benefit plans of the Company (the
               amounts described in clauses (A) through (D) hereof being
               referred to as the "Accrued Rights").

          Following such termination of Executive's employment by the Company
     for Cause or by Executive without Good Reason, except as set forth in this
     Section 8(a), Executive shall have no further rights to any compensation or
     any other benefits under this Agreement.

     b.   Disability or Death.
          -------------------

          (i)  Executive's employment hereunder shall terminate upon Executive's
          death or if Executive becomes physically or mentally incapacitated, as
          determined pursuant to the Company's long-term disability program as
          may be in effect from time to time (the "LTD Program"), and is
          therefore unable, for a period of time as determined under the LTD
          Program, to perform Executive's duties (such incapacity is hereinafter
          referred to as "Disability"). Any question as to the existence of the
          Disability of Executive as to which Executive and the Company cannot
          agree shall be determined in writing by a qualified independent
          physician mutually acceptable to Executive and the Company. If
          Executive and the Company cannot agree as to a qualified independent
          physician, each shall appoint such a physician and those two
          physicians shall select a third who shall make such determination in
          writing. The determination of Disability made in writing to the
          Company and Executive shall be final and conclusive for all purposes
          of the Agreement.

          (ii)  Upon termination of Executive's employment hereunder for either
          Disability or death, Executive or Executive's estate (as the case may
          be) shall be entitled to receive:

               (A)  the Accrued Rights; and

               (B)  a pro rata portion of Executive's annual target bonus based
               upon the percentage of the calendar year that shall have elapsed
               through the date of termination of the Executive's employment,
               payable when such bonus would have otherwise been payable had
               Executive's employment not terminated.

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          Following Executive's termination of employment due to death or
     Disability, except as set forth in this Section 8(b), Executive shall have
     no further rights to any compensation or any other benefits under this
     Agreement.

     c.   By the Company Without Cause, Expiration of Employment Term, or
Resignation by Executive for Good Reason.


          (i)  The Executive's employment hereunder may be terminated by the
          Company without Cause, by the Company's election not to extend the
          Employment Term, or, upon 60 days prior written notice, by Executive's
          resignation for Good Reason.

          (ii)  In the event that the Company elects not to extend the
          Employment Term pursuant to Section 1, unless Executive's employment
          is earlier terminated pursuant to paragraphs (a), (b) or (c) of this
          Section 8, Executive's termination of employment hereunder (whether or
          not Executive continues as an employee of the Company thereafter)
          shall be deemed to occur on the close of business on the day
          immediately preceding the next scheduled Extension Date.

          (iii)  For purposes of this Agreement, "Good Reason" shall mean: (A) a
          reduction in Executive's Base Salary or annual bonus opportunity or
          target bonus (other than any general salary reduction affecting at
          least the majority of salaried employees or annual incentive plan
          changes affecting all similarly situated officers of the Company,
          including any Executive Vice President, and provided that the
          establishment of reasonable performance targets by the Board will not
          constitute a reduction of annual bonus opportunity or target bonus),
          (B) a substantial diminution of Executive's duties and
          responsibilities, or (C) a transfer of Executive's primary workplace
          by more than thirty-five (35) miles from the Executive's workplace
          immediately prior to such transfer.

               Notwithstanding the foregoing, none of the events described in
          clauses (A), (B) or (C) of this Section 8(c)(ii) shall constitute Good
          Reason unless Executive shall have notified the Company in writing
          describing the events which constitute Good Reason and then only if
          the Company shall have failed to cure such event within thirty (30)
          days after the Company's receipt of such written notice. However, any
          termination of Executive's employment by the Company after delivery by
          the Executive to the Company of such notice shall be deemed to be a
          termination without Cause if Good Reason did exist at the time such
          notice was given by Executive.

          (iv)  If Executive's employment is terminated by the Company without
          Cause (other than by reason of death or Disability), as a result of
          the Company's nonrenewal of the Employment Term pursuant to Section 1
          hereof, or by Executive's resignation for Good Reason, Executive shall
          be entitled to receive:

                                       6
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                    (A)  the Accrued Rights;

                    (B)  subject to Executive's continued compliance with the
                    provisions of Section 9, an amount equal to two (the
                    "Severance Multiplier") times the sum of the (1) then Base
                    Salary and (2) then annual target bonus, payable in
                    accordance with normal payroll practices of the Company in
                    substantially equal installments over the 24 month period
                    following termination of employment; provided that the
                    aggregate amount described in this clause (B) shall be
                    reduced by the present value of any other cash severance or
                    termination benefits payable to Executive under any other
                    plans, programs or arrangements of the Company or its
                    affiliates; and

                    (C)   any rights to which Executive is entitled pursuant to
                    the certain Stock Option Agreements, of even date herewith,
                    by and between Executive and the Company, as well as any
                    rights to which Executive is entitled under the Premcor Inc.
                    1999 Stock Incentive Plan.

                         Notwithstanding the foregoing, in the event Executive's
                    employment is terminated under this Section 8(c) at any time
                    following a Change of Control (defined below), the Severance
                    Multiplier shall be increased from two to three, and any
                    severance amounts payable pursuant to Section 8(c)(iv)(B)
                    shall be payable in the form of a single, lump sum cash
                    payment within 10 days following termination of employment.

                    (D)  The Company, at its expense, shall provide the
                    Executive with the reasonable job relocation counseling
                    services of a firm chosen from time to time by the
                    Executive, for a period not to exceed 18 months after the
                    Date of Termination.

                    (E)  The Company shall maintain in full force and effect,
                    for the Executive's continued benefit, until the earlier of
                    (1) one year after the date of the termination of
                    Executive's employment or (2) the Executive's commencement
                    of full time employment with a new employer, all life
                    insurance, medical, dental, health and accident and
                    disability plans, programs or arrangements in which the
                    Executive was entitled to participate immediately prior to
                    the termination of Executive's employment at a cost to the
                    Executive no greater than the Executive paid while employed
                    by the Company, provided that the Executive's continued
                    participation is possible under the general terms and
                    provisions of such plans and programs. In the event that the
                    Executive's participation is barred, the Company shall
                    arrange to provide the Executive, at the Company's expense,
                    with benefits substantially similar to those which the
                    Executive is entitled to receive under such plans, programs
                    or arrangements, or pay cash in an amount after tax
                    sufficient to enable the Executive to purchase substantially
                    similar coverage for a one year period

                                       7
<PAGE>

                    on an individual basis, at a cost to the Executive no
                    greater than the Executive paid while employed. In the case
                    of the Executive's commencement of full time employment with
                    a new employer within the one year period, the Company
                    agrees to make up any differential in benefits between what
                    the Executive would have received from the Company in the
                    one year period and what the Executive receives from his new
                    employer, so that the Executive is ensured of receiving the
                    same benefits which he would have been entitled to receive
                    from the Company had his employment with the Company
                    continued for the one year period at a cost to the Executive
                    no greater than the Executive paid while employed.

               Following Executive's termination of employment by the Company
          without Cause (other than by reason of Executive's death or
          Disability), as a result of the Company's nonrenewal of the Employment
          Term pursuant to Section 1 hereof, or by Executive's resignation for
          Good Reason, except as set forth in this Section 8(c), Executive shall
          have no further rights to any compensation or any other benefits under
          this Agreement.

          d.   Notice of Termination. Any purported termination of employment by
          the Company or by Executive (other than due to Executive's death)
          shall be communicated by written Notice of Termination to the other
          party hereto in accordance with Section 11(h) hereof. For purposes of
          this Agreement, a "Notice of Termination" shall mean a notice which
          shall indicate the specific termination provision in this Agreement
          relied upon and shall set forth in reasonable detail the facts and
          circumstances claimed to provide a basis for termination of employment
          under the provision so indicated.

          e.   Definition of Change of Control. For purposes hereof, "Change of
          Control" shall mean any transaction, the result of which is that any
          Person (an "Acquiring Person") other than (i) Blackstone (defined
          below) or (ii) any Person, a majority of whose voting equity is owned
          by Blackstone, becomes the beneficial owner, directly or indirectly,
          of shares of stock of the Company or Premcor USA Inc. entitling such
          Acquiring Person to exercise 50% or more of the total voting power of
          all classes of stock of the Company or Premcor USA, Inc., as the case
          may be, entitled to vote in elections of directors. For purposes
          hereof, "Blackstone" shall mean, collectively, The Blackstone Group,
          Blackstone Capital Partners III Merchant Banking Fund L.P., and their
          affiliates (other than the Company and its subsidiaries) and "Person"
          shall mean a "person" as such term is used for purposes of Section
          13(d) or 14(d) of the Securities Exchange Act of 1934, as amended.

          f.   (i)  In the event it shall be determined that any payment,
               benefit or distribution (or combination thereof) by the Company,
               or by any other member of the same affiliated group with the
               Company (as determined under Code Section 280G(d)(5)) for the
               benefit of the Executive (whether paid or payable or distributed
               or distributable pursuant to the terms of this Agreement, or
               otherwise) (a "Payment") would be subject to the excise tax
               imposed by Section 4999 of the

                                       8
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               Internal Revenue Code of 1986, as amended from time to time (the
               "Code"), or any interest or penalties are incurred by the
               Executive with respect to such excise tax (other than interest or
               penalties incurred as a result of the failure of the Executive to
               file any tax return, or pay any tax (except any such failure to
               pay tax in accordance with the terms hereof), required by
               applicable law or to be filed or paid by the Executive) (such tax
               together with any such interest and penalties, hereinafter
               collectively referred to as the "Excise Tax"), the Executive
               shall be entitled to receive an additional payment (a "Gross-Up
               Payment") in an amount such that after payment by the Executive
               of taxes (including payroll taxes and any interest or penalties
               imposed with respect to such taxes, other than interest or
               penalties imposed as a result of the failure of the Executive to
               file any tax return or pay any tax (except any such failure to
               pay tax in accordance with the terms hereof), required by
               applicable law to be filed or paid by the Executive), including,
               without limitation, any income taxes (and any interest and
               penalties imposed with respect thereto, other than interest or
               penalties imposed as a result of the failure of the Executive to
               file any tax return or pay any tax (except any such failure to
               pay tax in accordance with the terms hereof), required by
               applicable law to be filed or paid by the Executive) and the
               Excise Tax imposed upon the Gross-Up Payment, the Executive
               retains an amount of the Gross-Up Payment equal to the Excise Tax
               imposed upon the Payments.

               (ii)  Subject to the provisions of subsection 8(g)(iii), all
               determinations required to be made under this subsection 8(g),
               including whether and when a Gross-Up Payment is required and the
               amount of such Gross-Up Payment and the assumptions to be
               utilized in arriving at such determination, shall be made by
               Deloitte & Touche LLP or, if Deloitte & Touche LLP is unable or
               unwilling to serve, then such nationally recognized accounting
               firm as the Company shall select (Deloitte & Touche LLP or such
               other accounting firm being the "Accounting Firm" ), which shall
               provide detailed supporting calculations both to the Company and
               the Executive within fifteen (15) business days of the receipt of
               notice from the Executive that there has been a Payment, or such
               earlier time as is requested by the Company. All fees and
               expenses of the Accounting Firm shall be borne solely by the
               Company. Any Gross-Up Payment, as determined pursuant to this
               Section 8(g), shall be paid by the Company to the Executive
               within five (5) days after the receipt of the Accounting Firm's
               determination. If the Accounting Firm determines that no Excise
               Tax is payable by the Executive, it shall so indicate to the
               Executive in writing. Any determination by the Accounting Firm
               shall be binding upon the Company and the Executive. As a result
               of the uncertainty in the application of Section 4999 of the Code
               at the time of the initial determination by the Accounting Firm
               hereunder, it is possible that Gross-Up Payments which will not
               have been made by the Company should have been made
               ("Underpayment"), consistent with the calculations required to be
               made hereunder. In the event that the Corporation exhausts its
               remedies pursuant to subsection 8(g)(iii) and the Executive
               thereafter is required to make a payment of any Excise Tax, the
               Accounting Firm shall determine the amount of the

                                       9
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               Underpayment that has occurred and any such Underpayment shall be
               promptly paid by the Corporation to or for the benefit of the
               Executive.

               (iii)  The Executive shall notify the Company in writing of any
               claim by the Internal Revenue Service that, if successful, would
               require the payment by the Company of the Gross-Up Payment. Such
               notification shall be given as soon as practicable but no later
               than ten (10) business days after the Executive is informed in
               writing of such claim and shall apprize the Company of the nature
               of such claim and the date on which such claim is requested to be
               paid. The Executive shall not pay such claim prior to the
               expiration of the thirty (30) day period following the date on
               which it gives such notice to the Company (or such shorter period
               ending on the date that any payment of taxes with respect to such
               claim is due). If the Company notifies the Executive in writing
               prior to the expiration of such period that it desires to contest
               such claim, the Executive shall:

                    (A)  give the Company any information requested by the
                    Company relating to such claim;

                    (B)  take such action in connection with contesting such
                    claim as the Company shall reasonably request in writing
                    from time to time, including, without limitation, accepting
                    legal representation with respect to such claim by an
                    attorney reasonably selected by the Company;

                    (C)  cooperate with the Company in good faith in order to
                    effectively contest such claim; and

                    (D)  permit the Company to participate in any proceedings
                    relating to such claim; provided, however, that the Company
                    shall bear and pay directly all costs and expenses
                    (including additional interest and penalties) incurred in
                    connection with such contest and shall indemnify and hold
                    the Executive harmless, on an after-tax basis, for any
                    Excise Tax or income tax (including interest and penalties
                    with respect thereto, other than interest or penalties
                    imposed as a result of the failure of the Executive to file
                    any tax return or pay any tax (except any such failure to
                    pay tax in accordance with the terms hereof), required by
                    applicable law to be filed or paid by the Executive) imposed
                    as a result of such representation and payment of costs and
                    expenses, Without limitation on the foregoing provisions of
                    this subsection 8(g)(iii), the Company shall control all
                    proceedings taken in connection with such content and, at
                    its sole option, may pursue or forego any and all
                    administrative appeals, proceedings, hearings and
                    conferences with the taxing authority in respect of such
                    claim and may, at its sole option, either direct the
                    Executive to pay the tax claimed and sue for a refund or
                    contest the claim in any permissible manner, and the
                    Executive agrees to prosecute such contest to a
                    determination before any administrative tribunal, in a court
                    of initial

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<PAGE>

                    jurisdiction and in one or more appellate courts, as the
                    Company shall determine; provided, however, that of the
                    Company directs the Executive to pay such claim and sue for
                    a refund, the Company shall advance the amount of such
                    payment to the Executive, on an interest-free basis, and
                    shall indemnify and hold the Executive harmless, on an
                    after-tax basis, from any excise Tax or income tax
                    (including interest or penalties with respect thereto, other
                    than interest or penalties imposed as a result of the
                    failure of the Executive to file any tax return or pay any
                    tax (except any such failure to pay tax in accordance with
                    the terms hereof), required by applicable law to be filed or
                    paid by the Executive) imposed with respect to such advance
                    or with respect to any imputed income with respect to such
                    advance; and provided, further, that if the Executive is
                    required to extend the statute of limitations to enable the
                    Company to contest such claim, the Executive may limit this
                    extension solely to such contested amount. The Company's
                    control of the contest shall be limited to issues with
                    respect to which a Gross-Up Payment would be payable
                    hereunder and the Executive shall be entitled to settle or
                    contest, as the case may be, any other issue raised by the
                    Internal Revenue Service or any other taxing authority.

               (iv) If, after the receipt by the Executive of an amount advanced
               by the Company pursuant to subsection 8(g)(iii), the Executive
               becomes entitled to receive any refund with respect to such
               claim, the Executive shall (subject to the Company's complying
               with the requirements of subsection 8(g)(iii)) promptly pay to
               the Company the amount of such refund (together with any interest
               paid or credited thereon after taxes applicable thereto). If,
               after the receipt by the Executive of an amount advanced by the
               Company pursuant to subsection 8(g)(iii), a determination is made
               that the Executive shall not be entitled to any refund with
               respect to such claim and the Company does not notify the
               Executive in writing of its intent to contest such denial of
               refund prior to the expiration of thirty (30) days after such
               determination, then such advance shall be forgiven and shall not
               be required to be repaid and the amount of such advance shall
               offset, to the extent thereof, the amount of Gross-Up Payment
               required to be paid.


     9.   Nondisclosure of Confidential Information; Non-Solicitation.
          -----------------------------------------------------------

          a.   At any time during or for a period of three years after
          Executive's employment with the Company, Executive shall not, without
          the prior written consent of the Company, use, divulge, disclose or
          make accessible to any other person, firm, partnership, corporation or
          other entity any Confidential Information (as hereinafter defined)
          pertaining to the business of the Company or any of its subsidiaries,
          except (i) while employed by the Company, in the business of and for
          the benefit of the Company, or (ii) when required to do so by a court
          of competent jurisdiction, by any governmental agency having
          supervisory authority over the business of the Company, or

                                       11
<PAGE>

          by any administrative body or legislative body (including a committee
          thereof) with jurisdiction to order Executive to divulge, disclose or
          make accessible such information. For purposes of this Section 8(a),
          "Confidential Information" shall mean non-public information
          concerning the financial data, strategic business plans, and other
          non-public, proprietary and confidential information of the Company,
          its subsidiaries, Blackstone (defined above), and their respective
          affiliates as in existence as of the date of Executive's termination
          of employment that, in any case, is not otherwise available to the
          public (other than by Executive's breach of the terms hereof).

          b.   In the course of Executive's employment Executive will acquire
          knowledge of Confidential Information and trade secrets. Executive
          acknowledges that the Confidential Information and trade secrets which
          the Company has provided and will provide to him could play a
          significant role were he to directly or indirectly be engaged in any
          business that competes with the Company or its subsidiaries. Executive
          agrees that, without the prior written consent of the Company, (i)
          during his employment with the Company and for a period of two years
          thereafter he shall not, on his own behalf or on behalf of any person,
          firm or company, directly or indirectly, solicit the business of any
          person or entity that has been a client or customer of the Company or
          its subsidiaries at any time during the 12 months immediately
          preceding such solicitation, and (ii) during his employment with the
          Company or for a period of one year thereafter he shall not, on his
          own behalf or on behalf of any person, firm or company, directly or
          indirectly, solicit or offer employment to any person who has been
          employed by the Company, its subsidiaries, or Blackstone in an
          executive or management capacity at any time during the 12 months
          immediately preceding such solicitation.

          c.   Executive and the Company agree that the foregoing covenants not
          to solicit are a reasonable covenant under the circumstances, and
          further agree that if in the opinion of any court of competent
          jurisdiction such restraints are not reasonable in any respect, such
          court shall have the right, power and authority to excise or modify
          such provision or provisions of these covenants as, to the court,
          shall appear not reasonable and to enforce the remainder of the
          covenant as so amended.

     10.  Specific Performance. Executive acknowledges and agrees that the
     Company's remedies at law for a breach or threatened breach of any of the
     provisions of Section 9 would be inadequate and, in recognition of this
     fact, Executive agrees that, in the event of such a breach or threatened
     breach, in addition to any remedies at law, the Company, without posting
     any bond, shall be entitled to cease making any payments or providing any
     benefit otherwise required by this Agreement and obtain equitable relief in
     the form of specific performance, temporary restraining order, temporary or
     permanent injunction or any other equitable remedy which may then be
     available.

     11.  Miscellaneous.
          -------------

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     a.   Governing Law. This Agreement shall be governed by and construed in
     accordance with the laws of the State of Missouri, without regard to
     conflicts of laws principles thereof.

     b.   Entire Agreement/Amendments. This Agreement contains the entire
     understanding of the parties with respect to the employment of Executive by
     the Company. There are no restrictions, agreements, promises, warranties,
     covenants or undertakings between the parties with respect to the subject
     matter herein other than those expressly set forth herein. This Agreement
     may not be altered, modified, or amended except by written instrument
     signed by the parties hereto. This Agreement supercedes all prior
     agreements and understandings (including verbal agreements) between
     Executive and the Company and/or its affiliates regarding the terms and
     conditions of Executive's employment with the Company and/or its affiliates

     c.  No Waiver. The failure of a party to insist upon strict adherence to
     any term of this Agreement on any occasion shall not be considered a waiver
     of such party's rights or deprive such party of the right thereafter to
     insist upon strict adherence to that term or any other term of this
     Agreement.

     d.  Severability. In the event that any one or more of the provisions of
     this Agreement shall be or become invalid, illegal or unenforceable in any
     respect, the validity, legality and enforceability of the remaining
     provisions of this Agreement shall not be affected thereby.

     e.  Assignment. This Agreement shall not be assignable by Executive. This
     Agreement may be assigned by the Company to a company which is a successor
     in interest to substantially all of the business operations of the Company.
     Such assignment shall become effective when the Company notifies Executive
     of such assignment or at such later date as may be specified in such
     notice. Upon such assignment, the rights and obligations of the Company
     hereunder shall become the rights and obligations of such successor
     company, provided that any assignee expressly assumes the obligations,
     rights and privileges of this Agreement.

     f.   Mitigation. If the Executive's employment hereunder is terminated for
     any reason, the Executive shall not be subject to any duty or obligation to
     seek alternate employment or other sources of income or benefits, or to
     mitigate his damages, or to any similar duty or obligation, and, except as
     specifically provided with respect to the continuation of benefits, all
     payment and other obligations of the Company under this Agreement shall not
     be subject to any rights of set-off, duty to mitigate or other reduction,
     and shall be paid and performed in full notwithstanding any alternate
     employment or other sources of income or benefits obtained or received or
     receivable by the Executive.

                                       13
<PAGE>

     g.   Successors; Binding Agreement. This Agreement shall inure to the
     benefit of and be binding upon personal or legal representatives,
     executors, administrators, successors, heirs, distributes, devises and
     legatees.

     h.   Notice. For the purpose of this Agreement, notices and all other
     communications provided for in the Agreement shall be in writing and shall
     be deemed to have been duly given when delivered or mailed by United States
     registered mail, return receipt requested, postage prepaid, addressed to
     the respective addresses set forth below Agreement, or to such other
     address as either party may have furnished to the other in writing in
     accordance herewith, except that notice of change of address shall be
     effective only upon receipt.

     If to the Company:
          The Premcor Refining Group Inc.
            Attention:  Corporate Secretary
          8182 Maryland Avenue
          Clayton, Missouri  63105

     If to Executive:
          To the most recent address of Executive set forth in the personnel
     records of the Company.

     i.   Withholding Taxes. The Company may withhold from any amounts payable
     under this Agreement such Federal, state and local taxes as may be required
     to be withheld pursuant to any applicable law or regulation.

     j.   Counterparts. This Agreement may be signed in counterparts, each of
     which shall be an original, with the same effect as if the signatures
     thereto and hereto were upon the same instrument.

     k.   Legal and Professional Fees. The Corporation shall pay to the
     Executive all reasonable legal and professional fees and expenses incurred
     by the Executive in seeking to obtain or enforce any right or benefit
     provided by this Agreement.

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

                                       THE PREMCOR REFINING GROUP INC.


                                       By: /s/ Jeffry N. Quinn
                                          -------------------------

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<PAGE>

                                       Name:   Jeffry N. Quinn
                                             -----------------------------
                                       Title:  Executive Vice President
                                             -----------------------------

                                       EZRA C. HUNT

                                         /s/ Ezra C. Hunt
                                       -----------------------------
                                       201 Woodward Boulevard
                                       Tulsa, Oklahoma  74114

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<PAGE>

                                   EXHIBIT A
             (Financial and Tax Preparation and Planning Services)


 .  Financial consulting services and tax preparation and planning services from
   AYCO, Inc.

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