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                       PREMCOR 2002 EQUITY INCENTIVE PLAN

1.   PURPOSE OF THE PLAN

     The purpose of the Plan is to aid the Company and its Affiliates in
recruiting, retaining and rewarding key employees, directors or consultants of
outstanding ability and to motivate such employees, directors or consultants to
exert their best efforts on behalf of the Company and its Affiliates by
providing incentives through the granting of Awards. The Company expects that it
will benefit from the added interest which such key employees, directors or
consultants will have in the welfare of the Company as a result of their
proprietary interest in the Company's success.

2.   DEFINITIONS

     The following capitalized terms used in the Plan have the respective
meanings set forth in this Section:

         (a)   Act: The Securities Exchange Act of 1934, as amended, or any
               successor thereto.

         (b)   Affiliate: Any entity directly or indirectly controlling,
               controlled by, or under common control with, the Company or any
               other entity designated by the Board in which the Company or an
               Affiliate has an interest.

         (c)   Award: An Option, Stock Appreciation Right or Other Share-Based
               Award granted pursuant to the Plan.

         (d)   Beneficial Owner: A "beneficial owner," as such term is defined
               in Rule 13d-3 under the Act (or any successor rule thereto).

         (e)   Blackstone: 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 partner.

         (f)   Board: The Board of Directors of the Company.

         (g)   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 Act), other than Blackstone, is or becomes the
               "beneficial owner" (as defined in Rule 13d-3 under the Act),
               directly or indirectly, of securities of the Company representing
               50% or more of the combined voting power of its then outstanding
               securities entitled to vote in the election of directors.

         (h)   Code: The Internal Revenue Code of 1986, as amended, or any
               successor thereto.

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         (i)   Committee: The Compensation Committee of the Board, or such other
               committee as may be appointed by the Board in accordance with
               Section 4 of the Plan.

         (j)   Company: Premcor Inc., a Delaware corporation.

         (k)   Effective Date: The date the Board approves the Plan, or such
               later date as is designated by the Board.

         (l)   Fair Market Value: If the Shares are traded on NASDAQ, the Fair
               Market Value of the Shares as of any date shall be the closing
               sale price on that date of a Share as reported in the NASDAQ
               National Market Issues quotations of the Midwest Edition of the
               Wall Street Journal. If the Shares are traded on the New York
               Stock Exchange, the Fair Market Value of the Shares as of any
               date shall be the closing sale price on that date of a Share as
               reported on the New York Stock Exchange Composite Tape (or, if
               the Shares are not traded on NASDAQ or the New York Stock
               Exchange, as applicable, on such date, on the next preceding date
               on which it was so traded; and if there should not be a public
               market for the Shares on such date, the Fair Market Value shall
               be the value established by the Committee in good faith.

         (m)   ISO: An Option that is also an incentive stock option, as
               described in Section 422 of the Code, granted pursuant to Section
               6(c) of the Plan.

         (n)   LSAR: A limited stock appreciation right granted pursuant to
               Section 7(d) of the Plan.

         (o)   Option: A stock option granted pursuant to Section 6 of the Plan.

         (p)   Option Price: The purchase price per Share under the terms of an
               Option, as determined pursuant to Section 6(a) of the Plan.

         (q)   Other Share-Based Awards: Awards granted pursuant to Section 8 of
               the Plan.

         (r)   Participant: An employee, director or consultant of the Company
               or an Affiliate who is selected by the Committee to participate
               in the Plan.

         (s)   Person: A "person," as such term is used for purposes of Section
               13(d) or 14(d) of the Act (or any successor section thereto).

         (t)   Plan: The Premcor 2002 Equity Incentive Plan.

         (u)   RSU: A restricted stock unit, granted pursuant to Section 8 of
               the Plan, that represents the right to receive a Share.

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         (v)   Shares: Shares of common stock of the Company, subject to
               coordination with Section 9 hereof.

         (w)   Stock Appreciation Right: A stock appreciation right granted
               pursuant to Section 7 of the Plan.

         (x)   Subsidiary: Any entity that, directly or indirectly, is
               controlled by the Company, and any entity in which the Company
               has an equity interest, in either case as determined by the
               Committee.

3.   SHARES SUBJECT TO THE PLAN

         The total number of Shares of common stock that may be used to satisfy
Awards under the Plan initially is 1,500,000. The Shares may consist, in whole
or in part, of unissued Shares or previously-issued Shares. The issuance of
Shares upon the exercise or payment of an Award shall reduce the total number of
Shares available under the Plan, as applicable. Shares which are subject to
Awards which terminate, lapse or are cancelled may again be used to satisfy
Awards under the Plan. If the Option Price of any Option granted under the Plan
is satisfied by delivering Shares to the Company, only the number of Shares
issued net of the Shares delivered shall be deemed delivered for purposes of
determining the maximum numbers of Shares available under the Plan. To the
extent any Shares subject to an Award are not delivered to a Participant because
such Shares are used to satisfy an applicable tax-withholding obligation, such
Shares shall not be deemed to have been delivered for purposes of determining
the maximum number of Shares available under the Plan.

4.   ADMINISTRATION

         The Plan shall be administered by the Committee, which may delegate its
duties and powers in whole or in part as it determines, including to a
subcommittee consisting solely of at least two individuals who are intended to
qualify as "non-employee directors" within the meaning of Rule 16b-3 under the
Act (or any successor rule thereto). The Committee may grant Awards under this
Plan only to Participants; provided that Awards may also, in the discretion of
the Committee, be made under the Plan in assumption of, or in substitution for,
outstanding awards previously granted by the Company or its Affiliates or a
company that becomes an Affiliate. The number of Shares underlying such
substitute Awards shall be counted against the aggregate number of Shares
available for Awards under the Plan. The Committee is authorized to interpret
the Plan, to establish, amend and rescind any rules and regulations relating to
the Plan, and to make any other determinations that it deems necessary or
desirable for the administration of the Plan. The Committee may correct any
defect or supply any omission or reconcile any inconsistency in the Plan in the
manner and to the extent the Committee deems necessary or desirable. Any
decision of the Committee in the interpretation and administration of the Plan,
as described herein, shall lie within its sole and absolute discretion and shall
be final, conclusive and binding on all parties concerned (including, but not
limited to, Participants and their beneficiaries or successors). The Committee
shall have the full power and authority to establish the terms and conditions of
any Award consistent with the provisions of the Plan and to waive any such terms
and conditions at any time, in its sole discretion (including, without
limitation, accelerating or waiving any vesting conditions and/or accelerating
any payment). The

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Committee shall require payment of any amount it may determine to be necessary
to withhold for federal, state, local or other taxes of any relevant
jurisdiction as a result of the granting, vesting or exercise of an Award, or
upon the sale of Shares acquired by the granting, vesting or exercise of an
Award. For avoidance of doubt, if at any time the Committee determines that it
has not received or required sufficient payment in respect of such withholding,
the Committee is authorized to require such additional payments as it determines
are necessary, and may withhold from such sources as it determines are
necessary, including by payroll deductions.

5.   LIMITATIONS

         No Award may be granted under the Plan after the tenth anniversary of
the Effective Date, but Awards theretofore granted may extend beyond that date.

6.   TERMS AND CONDITIONS OF OPTIONS

         Options granted under the Plan shall be, as determined by the
Committee, non-qualified stock options or ISOs for United States federal income
tax purposes (or other types of Options in jurisdictions outside the United
States), as evidenced by the related Award, and shall be subject to the
foregoing and the following terms and conditions and to such other terms and
conditions, not inconsistent therewith, as the Committee shall determine:

         (a)   Option Price; Exercisability. Options granted under the Plan
               shall have an Option Price, and shall be exercisable at such time
               and upon such terms and conditions, as may be determined by the
               Committee.

         (b)   Exercise of Options. Except as otherwise provided in the Plan or
               in an Award, an Option may be exercised for all, or from time to
               time any part, of the Shares for which it is then exercisable.
               For purposes of this Section 6 of the Plan, the exercise date of
               an Option shall be the later of the date a notice of exercise is
               received by the Company and, if applicable, the date payment is
               received by the Company pursuant to clauses (i), (ii) or (iii) in
               the following sentence. Except as otherwise provided in an Award,
               the purchase price for the Shares as to which an Option is
               exercised shall be paid in full at the time of exercise at the
               election of the Participant (i) in cash or its equivalent (e.g.,
               by check), (ii) to the extent permitted by the Committee, in
               Shares having a Fair Market Value equal to the aggregate Option
               Price for the Shares being purchased and satisfying such other
               requirements as may be imposed by the Committee, provided, that
               such Shares have been held by the Participant for no less than
               six months (or such other period as established from time to time
               by the Committee or generally accepted accounting principles),
               (iii) partly in cash and, to the extent permitted by the
               Committee, partly in such Shares, provided, that such Shares have
               been held by the Participant for no less than six months (or such
               other period as established from time to time by the Committee or
               generally accepted accounting principles), or (iv) through the
               delivery of irrevocable instructions to a broker to sell Shares
               obtained upon the exercise of the Option and deliver promptly to
               the Company an amount

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               out of the proceeds of such sale equal to the aggregate Option
               Price for the Shares being purchased. The Committee may authorize
               the Company to make or facilitate loans to Participants to enable
               them to exercise Options. The Committee may permit Participants
               to exercise Options in joint-tenancy with the Participant's
               spouse. No Participant shall have any rights to dividends or
               other rights of a shareholder with respect to Shares subject to
               an Option until the Participant has given written notice of
               exercise of the Option, the Participant has paid in full for such
               Shares, the Shares in question have been recorded in the
               Company's register of shareholders, and, if applicable, the
               Participant has satisfied any other conditions imposed by the
               Committee pursuant to the Plan.

         (c)   ISOs. The Committee may grant Options under the Plan that are
               intended to be ISOs. No ISO shall have a per Share Option Price
               of less than the Fair Market Value of a Share on the date granted
               or have a term in excess of ten years; provided, however, that no
               ISO may be granted to any Participant who at the time of such
               grant, owns more than ten percent of the total combined voting
               power of all classes of shares of the Company or of any
               Subsidiary, unless (i) the Option Price for such ISO is at least
               110% of the Fair Market Value of a Share on the date the ISO is
               granted and (ii) the date on which such ISO terminates is a date
               not later than the day preceding the fifth anniversary of the
               date on which the ISO is granted. Any Participant who disposes of
               Shares acquired upon the exercise of an ISO either (A) within two
               years after the date of grant of such ISO or (B) within one year
               after the transfer of such Shares to the Participant, shall
               notify the Company of such disposition and of the amount realized
               upon such disposition.

         (d)   Attestation. Wherever in this Plan or any agreement evidencing an
               Award a Participant is permitted to pay the Option Price by
               delivering Shares, the Participant may, subject to procedures
               satisfactory to the Committee, satisfy such delivery requirement
               by presenting proof of record ownership of such Shares, or, to
               the extent permitted by the Committee, beneficial ownership of
               such Shares, in which case the Company shall treat the Option as
               exercised without further payment and shall withhold such number
               of Shares from the Shares acquired by the exercise of the Option.

7.   TERMS AND CONDITIONS OF STOCK APPRECIATION RIGHTS

         (a)   Grants. The Committee also may grant (i) a Stock Appreciation
               Right independent of an Option or (ii) a Stock Appreciation Right
               in connection with an Option, or a portion thereof. A Stock
               Appreciation Right granted pursuant to clause (ii) of the
               preceding sentence (A) may be granted at the time the related
               Option is granted or at any time prior to the exercise or
               cancellation of the related Option, (B) shall cover the same
               Shares covered by an Option (or such lesser number of Shares as
               the Committee may determine) and (C) shall be subject to the same
               terms and conditions as

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               such Option except for such additional limitations as are
               contemplated by this Section 7 (or such additional limitations as
               may be included in a Stock Appreciation Right Award).

         (b)   Terms. The exercise price per Share of a Stock Appreciation Right
               shall be an amount determined by the Committee. Each Stock
               Appreciation Right granted independent of an Option shall entitle
               a Participant upon exercise to a payment from the Company of an
               amount equal to (i) the excess of (A) the Fair Market Value on
               the exercise date of one Share over (B) the exercise price per
               Share, times (ii) the number of Shares covered by the Stock
               Appreciation Right. Each Stock Appreciation Right granted in
               conjunction with an Option, or a portion thereof, shall entitle a
               Participant to surrender to the Company the unexercised Option,
               or any portion thereof, and to receive from the Company in
               exchange therefor an amount equal to (I) the excess of (x) the
               Fair Market Value on the exercise date of one Share over (y) the
               Option Price per Share, times (II) the number of Shares covered
               by the Option, or portion thereof, which is surrendered. The date
               a notice of exercise is received by the Company shall be the
               exercise date. Payment shall be made in Shares or in cash, or
               partly in Shares and partly in cash (any such Shares valued at
               such Fair Market Value), all as shall be determined by the
               Committee. Stock Appreciation Rights may be exercised from time
               to time upon actual receipt by the Company of written notice of
               exercise stating the number of Shares with respect to which the
               Stock Appreciation Right is being exercised. No fractional Shares
               will be issued in payment for Stock Appreciation Rights, but
               instead cash will be paid for a fraction or, if the Committee
               should so determine, the number of Shares will be rounded
               downward to the next whole Share.

         (c)   Limitations. The Committee may impose, in its discretion, such
               conditions upon the exercisability or transferability of Stock
               Appreciation Rights as it may deem fit.

         (d)   Limited Stock Appreciation Rights. The Committee may grant LSARs
               that are exercisable upon the occurrence of specified contingent
               events. Such LSARs may provide for a different method of
               determining appreciation, specify that payment will be made only
               in cash and provide that any related Awards are not exercisable
               while such LSARs are exercisable. Unless the context otherwise
               requires, whenever the term "Stock Appreciation Right" is used in
               the Plan, such term shall include LSARs.

8.   OTHER SHARE-BASED AWARDS

         The Committee, in its sole discretion, may grant Awards of Shares,
Awards of restricted Shares, Awards of RSUs and other Awards that are valued in
whole or in part by reference to, or are otherwise based on the Fair Market
Value, of Shares ("Other Share-Based

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Awards"). Such Other Share-Based Awards shall be in such form, and dependent on
such conditions, as the Committee shall determine, including, without
limitation, the right to receive one or more Shares (or the equivalent cash
value of such Shares) upon the completion of a specified period of service, the
occurrence of an event and/or the attainment of performance objectives. Other
Share-Based Awards may be granted alone or in addition to any other Awards
granted under the Plan. Subject to the provisions of the Plan, the Committee
shall determine: (i) to whom and when Other Share-Based Awards will be made;
(ii) the number of Shares to be awarded under (or otherwise related to) such
Other Share-Based Awards; (iii) whether such Other Share-Based Awards shall be
settled in cash, Shares or a combination of cash and Shares; and (iv) all other
terms and conditions of such Other Share-Based Awards (including, without
limitation, the vesting provisions thereof and provisions ensuring that all
Shares so awarded and issued shall be fully paid and non-assessable)

9.   ADJUSTMENTS UPON CERTAIN EVENTS

         Notwithstanding any other provisions in the Plan to the contrary, the
following provisions shall apply to all Awards granted under the Plan:

         (a)   Generally. In the event of any change in the outstanding Shares
               after the Effective Date by reason of any Share dividend or
               split, reorganization, recapitalization, merger, consolidation,
               spin-off or combination transaction or exchange of Shares or
               other corporate exchange, or any distribution to shareholders of
               Shares other than regular cash dividends or any transaction
               similar to the foregoing, the Committee in its sole discretion
               and without liability to any person may make such substitution or
               adjustment, if any, as it deems to be equitable, as to (i) the
               number or kind of Shares or other securities issued or reserved
               for issuance pursuant to the Plan or pursuant to outstanding
               Awards, (ii) the Option Price or exercise price of any Stock
               Appreciation Right, and/or (iii) any other affected terms of any
               Award.

         (b)   Change in Control. In the event of a Change in Control after the
               Effective Date, the Committee may, in its sole discretion,
               provide for: (i) the accelerated vesting or exercisability of any
               outstanding Awards then held by Participants that are otherwise
               unexercisable or unvested, as the case may be, to the extent
               determined by the Committee and as of a date selected by the
               Committee; (ii) the termination of an Award upon the consummation
               of the Change in Control, and the payment of a cash amount in
               exchange for the cancellation of an Award which, in the case of
               Options and Stock Appreciation Rights, may equal the excess, if
               any, of the Fair Market Value of the Shares subject to such
               Options or Stock Appreciation Rights over the aggregate exercise
               price of such Options or Stock Appreciation Rights; and/or (iii)
               the issuance of substitute Awards that will substantially
               preserve the otherwise applicable terms of any affected Awards
               previously granted hereunder.

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10.  NO RIGHT TO EMPLOYMENT OR AWARDS

     The granting of an Award under the Plan shall impose no obligation on the
Company or any Affiliate to continue the employment or service or consulting
relationship of a Participant and shall not lessen or affect the Company's or
Affiliate's right to terminate the employment or service or consulting
relationship of such Participant. No Participant or other person shall have any
claim to be granted any Award, and there is no obligation for uniformity of
treatment of Participants, or holders or beneficiaries of Awards. The terms and
conditions of Awards and the Committee's determinations and interpretations with
respect thereto need not be the same with respect to each Participant (whether
or not such Participants are similarly situated).

11.  SUCCESSORS AND ASSIGNS

     The Plan shall be binding on all successors and assigns of the Company and
a Participant, including without limitation, the estate of such Participant and
the executor, administrator or trustee of such estate, or any receiver or
trustee in bankruptcy or representative of the Participant's creditors.

12.  NONTRANSFERABILITY OF AWARDS

     Unless otherwise determined by the Committee, an Award shall not be
transferable or assignable by the Participant other than by will or by the laws
of descent and distribution. An Award exercisable after the death of a
Participant may be exercised by the legatees, personal representatives or
distributees of the Participant.

13.  AMENDMENTS OR TERMINATION

     The Board may amend, alter or discontinue the Plan, but no amendment,
alteration or discontinuation shall be made which would (i) increase the maximum
number of shares available for Awards under the Plan (other than amendments
having such purpose that may be approved by the Board prior to the effective
date of the Company's initial public offering of Shares pursuant to an effective
registration statement filed under the Act) or (ii) without the consent of a
Participant, diminish any of the rights of the Participant under any Award
theretofore granted to such Participant under the Plan; provided, however, that
the Committee may amend the Plan in such manner as it deems necessary to permit
Awards to meet the requirements of the Code or other applicable laws.

14.  INTERNATIONAL PARTICIPANTS

     With respect to Participants, if any, who reside or work outside the United
States of America, the Committee may, in its sole discretion, amend the terms of
the Plan or Awards with respect to such Participants in order to conform such
terms with the provisions of local law, and the Committee may, where
appropriate, establish one or more sub-plans to reflect such amended or varied
provisions.

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15.  CHOICE OF LAW

     The Plan shall be governed by and construed in accordance with the laws of
the State of New York without regard to conflicts of laws.

16.  EFFECTIVENESS OF THE PLAN

     The Plan shall be effective as of the Effective Date, subject to the
approval of the shareholders of the Company.