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                                                                   Exhibit 10.39

                              SEPARATION AGREEMENT
                               AND GENERAL RELEASE

         This Separation Agreement and General Release ("Agreement") is
effective as of the date indicated herein below by and between Jeffry N. Quinn
("Executive") and Premcor Inc. ("Premcor").

         WHEREAS, Executive has been employed by Premcor, since March 1, 2000,
most recently pursuant to a written Employment Agreement dated June 1, 2002 (the
"Employment Agreement"); and

         WHEREAS, Executive and Premcor have agreed that Executive shall
terminate his employment with Premcor and that such termination of employment
shall be deemed to be a termination by Premcor "without Cause" or a "resignation
for Good Reason" as such terms are defined in the Employment Agreement; and

         WHEREAS, the Employment Agreement sets forth the benefits to which
Executive is entitled to receive upon termination of his employment and requires
that Executive enter into a full and complete release of Premcor from any and
all claims which Executive may have for whatever reason or cause in connection
with Executive's employment and termination thereof (including, without
limitation, any rights under an employment agreement which may then be in
effect), other than those obligations specifically set out in the Employment
Agreement; and

         WHEREAS, Executive and Premcor desire to settle fully and finally all
matters between them, including, but not limited to, any and all disputes which
may have arisen out of Executive's employment with Premcor, or his separation
therefrom.

         NOW THEREFORE, for and in consideration of the mutual releases,
covenants and undertakings hereinafter set forth, and for other good and
valuable consideration, which each party hereby acknowledges, it is agreed as
follows:

1)       Termination of Employment. Executive elects to resign, effective
         November 1, 2002, from his position as Executive Vice President,
         Secretary and General Counsel of Premcor and any of its affiliates, and
         from any membership on any Board of Directors (and any committees
         thereof) of any of its affiliates. (November 1, 2002 shall hereinafter
         be referred to as the "Separation Date".) Effective as of the
         Separation Date, Executive's employment with Premcor shall terminate
         and such termination shall be considered a termination without Cause or
         a resignation for Good Reason as such terms are defined in the
         Employment Agreement.

2)       Severance Payments and Benefits. Upon receipt of this Agreement signed
         by Executive and upon expiration of the seven (7) day revocation period
         set out in paragraph 5 below, Premcor agrees to provide the following
         payments and benefits in consideration and exchange for the Executive's
         promises, agreements and obligations set forth herein.

         (A)      Salary Continuation. Premcor shall continue to pay Executive
                  his base salary through his Separation Date, plus any and all
                  other benefits that Executive currently receives.

         (B)      Employee Benefits. Premcor shall provide the Executive with
                  such Employee Benefits (as such term is defined in the
                  Employment Agreement), if any, as to which Executive may be
                  entitled under the employee benefit plans of Premcor.

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         (C)      Severance Pay. Premcor agrees to pay Executive a lump sum cash
                  payment in the amount equal to One Million One Hundred
                  Sixty-Five Thousand Dollars ($1,165,000.00). The parties agree
                  that such payment shall be paid on January 2, 2003.

         (D)      Outplacement. Premcor shall provide the Executive with Lee
                  Hecht Harrison's Signature Level outplacement or career
                  transition counseling services. The cost for such service to
                  Premcor shall not exceed Thirty-five Thousand Dollars
                  ($35,000).

         (D)      Vacation. Premcor agrees to pay Executive a lump sum payment
                  in the amount of Nine Thousand Six Hundred Fifteen Dollars and
                  38/100 ($9,615.38) representing the balance of Executive's
                  earned but unused vacation entitlement.

         (E)      Business Expenses. Executive shall be reimbursed for any
                  unreimbursed business expenses properly incurred by Executive
                  prior to Executive's Separation Date.

         (F)      Relocation Advance. Executive has previously received an
                  advance under the Premcor Executive Relocation Program.
                  Premcor shall not seek reimbursement of such amount.

         (G)      Senior Executive Retirement Plan. Executive agrees to waive
                  any and all rights to any benefits that he may have been
                  entitled to receive pursuant to the Premcor Senior Executive
                  Retirement Plan.

3)       Stock Options.

         (A)      Time Vesting Stock Options. Executive holds options to
                  purchase 60,000 shares of the common stock of the Company
                  pursuant to the Clark Refining Holdings Inc. 1999 Stock
                  Incentive Plan (the "1999 Plan") as evidenced by a Stock
                  Option Certificate and Agreement dated March 1, 2000, which is
                  attached hereto as Exhibit A. The rights of Executive with
                  regard to such options shall be governed by such Option
                  Certificate and Agreement and the 1999 Plan.

         (B)      Performance Accelerated Options. Executive holds options to
                  purchase 60,000 shares of the common stock of the Company
                  pursuant to the Clark Refining Holdings Inc. 1999 Stock
                  Incentive Plan as evidenced by a Stock Option Certificate and
                  Agreement (Performance Vesting) dated March 1, 2000, which is
                  attached hereto as Exhibit B. The rights of Executive with
                  regard to such options shall be governed by such Option
                  Certificate and Agreement and the 1999 Plan.

         (C)      Premcor Stock Incentive Plan Options. Executive holds options
                  to purchase 50,000 shares of the common stock of the Company
                  pursuant to the 2002 Premcor Stock Incentive Plan (the "2002
                  Plan") and Stock Option Certificate dated April 29, 2002,
                  which is attached as Exhibit C. The rights of Executive with
                  regard to such options shall be governed by such Stock Option
                  Certificate and the 2002 Plan.

4)       Release of Claims and Agreement Not to File Suit. In consideration of
         the payments, benefits and rights provided to Executive under the terms
         of this Agreement, Executive agrees as follows:

         (A)      Executive hereby forever releases and discharges Premcor Inc.,
                  and any affiliated or subsidiary corporations or divisions,
                  and their successors and assigns, and each of their present
                  and former directors, officers, stockholders, employees,
                  attorneys and agents (collectively "Releasees") from any and
                  all matters, claims, demands, damages, causes of

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                  action, debts, liabilities, controversies, judgments and suits
                  of every kind and nature whatsoever, which have arisen or
                  could arise between Executive and Releasees for matters,
                  actions or inactions which Executive may have or claim to have
                  by reason of his employment with Premcor or his separation
                  from employment. Such released claims include, but are not
                  limited to, claims under any contract or agreement with the
                  Releasees, whether oral, implied or in writing, including but
                  not limited to Employment Agreement dated June 1, 2002, the
                  claims of discrimination under Title VII of the Civil Rights
                  Act of 1964, as amended, 42 U.S.C. Section 2000e, et seq., the
                  Age Discrimination in Employment Act of 1967, as amended, 29
                  U.S.C. Section 621, et seq., the Americans with Disabilities
                  Act, 42 U.S.C. Section 12101, et seq., the Employee Retirement
                  Income Security Act of 1974, as amended, 29 U.S.C. Section
                  1001, et seq., the Fair Labor Standards Act of 1938, 29 U.S.C.
                  Section 201, et seq., the Rehabilitation Act of 1973, 29
                  U.S.C. Section 701, et seq., the Worker Adjustment and
                  Retraining Notification Act of 1988, 29 U.S.C. Section 2101,
                  et seq., Connecticut Fair Employment Practices Act, Chapter
                  563, Sec. 31-122 et seq. Connecticut Workers' Compensation
                  Act, Chapter 568, Sec. 31-275 et seq. Connecticut Unemployment
                  Compensation Act, Chapter 567, Sec. 31-222 et seq. the
                  Missouri Workers' Compensation Act, Mo.Rev.Stat. Sec. 288.010
                  et seq., the Missouri Human Rights Act, Mo.Rev.Stat. Sec.
                  213.010 et seq., and any other federal, state or municipal
                  statues or ordinances relating to discrimination in
                  employment; claims of wrongful or unjust discharge,
                  defamation, personal injury, emotional distress, invasion of
                  privacy, or other tort claims; claims for unpaid wages or
                  other entitlements or payments; and claims of breach of
                  contract arising from or during Executive's employment with
                  Premcor, including Executive's separation from employment
                  other than those obligations specifically set out in herein.

         (B)      Other than an action to enforce the terms of the Employment
                  Agreement or this Seperation Agreement, Executive will not
                  file or otherwise submit any claim, complaint or action to any
                  agency, court, organization, or judicial forum (nor will he
                  permit any person, group of persons, or organizations to take
                  such action on his behalf) against the Releasees, or any one
                  acting on their behalf, arising out of any action or
                  non-actions on the part of the Releasees which occurred up to
                  the effective date of this Agreement. In the event that any
                  person or entity should bring such a charge, claim, complaint,
                  or action on Executive's behalf, Executive hereby waives and
                  forfeits any right to recovery under said claim and will
                  exercise every good faith effort to have such claim dismissed.

         (C)      In the event Executive violates this Agreement by suing the
                  Releasees, Executive agrees that he will pay all costs and
                  expenses of defending against the suit incurred by the
                  Releasees, including, but not limited to, reasonable attorney
                  fees and costs of litigation, and that he shall hold the
                  Releasees harmless against any judgment which may be brought
                  against them.

         (D)      Executive acknowledges and agrees that he is not owed and will
                  not be entitled to any other payment of any kind from Premcor
                  except as expressly provided for herein.

5)       Time for Consideration and Revocation. Executive understands that one
         aspect of this Agreement is the waiver by the Executive of any claims
         which Executive may have against Premcor as of the date he signs the
         Agreement, including claims arising under the Age Discrimination and
         Employment Act ("ADEA") of 1967, as amended, 29 U.S.C. Section 621.
         This waiver does not require Executive to waive any rights or claims
         that may arise after the date Executive signs this Agreement. Executive
         understands that he has twenty-one (21) calendar days

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         from his receipt of this Agreement to consider and accept it. Executive
         further understands that he may revoke this agreement within seven (7)
         calendar days after signing it and that the Agreement does not become
         effective and the valuable consideration specified above will not be
         paid or granted. The parties understand and agree that the
         aforementioned seven (7) day revocation period pertains only to
         Executive's release of age discrimination claims under the ADEA and
         agree that no other term or condition of this Agreement may be
         rescinded. Executive agrees that if he rescinds the release of any age
         claim, Premcor may, at its sole and absolute discretion, decide whether
         this whole Agreement shall be voided.

6)       Consultation With An Attorney. Executive acknowledges that he has been
         advised to consult an attorney (at his expense) concerning the meaning
         and legal implications of this Agreement before signing it. Executive
         affirms that he has been afforded sufficient time to review this
         Agreement and to seek counsel in order to decide whether to sign, that
         he understands fully all terms of this Agreement, and that he has
         signed this Agreement of his own free will and under no threat or
         duress by Premcor or any other person.

7)       Voluntary Agreement. Executive further acknowledges that he understands
         this Agreement, the claims he is releasing, the promises and agreements
         he is making, and the effect of him signing this Agreement. Executive
         further represents, declares and agrees that he voluntarily accepts the
         consideration described above for the purpose of making a full and
         final compromise, adjustment and settlement of all claims or potential
         claims against Premcor.

8)       Restrictive Covenants. Executive agrees that as a condition of his
         receipt of the benefits and payments provided for in Section 2 above,
         he shall comply with the applicable provisions of Sections 9 and 10 of
         the Employment Agreement dated June 1, 2002 (providing for certain
         restrictive covenants) as if those provisions were included herein by
         reference and made a part of this Agreement.

9)       Cooperation. Executive agrees to cooperate completely and to the extent
         reasonably required by Premcor in order to assure a smooth transition
         of pending matters that are or will be assigned to other staff.
         Executive agrees to assist Premcor in matters that may arise from time
         to time in connection with Executive's former duties and
         responsibilities. If Executive receives an inquiry from a third party
         or a subpoena or other court or legal document relating in any way to
         Premcor, Executive will immediately provide the General Counsel notice
         of the inquiry or service of such subpoena or other court or legal
         document.

10)      Return of Property. Executive agrees to immediately return all property
         belonging to Premcor, including, but not limited to, keys, security
         cards, credit cards, parking card, , computers, equipment, manuals,
         policy books or memoranda, and the like.

11)      No Admission of Wrong Doing. The parties to this Agreement agree that
         nothing in this Agreement is an admission by any party hereto of any
         wrong doing, either in violation of an applicable law or laws, and that
         nothing in this Agreement is to be construed as such by any person.

12)      Choice of Law. This Agreement shall be governed in all respects as to
         validity, construction, and performance, or otherwise, by the laws of
         the State of New York, without regard to conflicts of laws principles
         thereof. Any suit, action or proceeding related to this Agreement, or
         any judgment entered by any court related to this Agreement, may be
         brought only in any court of competent jurisdiction in the State of New
         York, and the parties hereby submit to the exclusive jurisdiction of
         such courts.

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13)      Modification. The parties hereto agree that this Agreement may not be
         modified, altered, or changed except by written agreement signed by the
         parties hereto.

14)      Indemnity Agreement. The parties acknowledge that the Indemnity
         Agreement dated August 9, 2002 by and between Executive and Premcor
         shall remain in full force and effect and shall be incorporated herein
         by reference as if it were part of this Agreement.

15)      No Reliance. The parties have not relied on any representations,
         promises, or agreements of any kind made to them in connection with
         this Agreement, except for those set forth in this Agreement.

16)      Binding Effect. This Agreement shall inure to the benefit of and be
         binding upon the parties hereto, their successors and assigns, without
         the need of formal assignment.

17)      Capacity to Settle. Executive represents and warrants that he has no
         legal impediments (including bankruptcies) to fully and completely
         settle all claims and to sign this Agreement. Executive further
         warrants that he is the sole owner of all the claims he has released in
         this Agreement, and that he has not heretofore assigned or transferred,
         or purported to assign or transfer, to any person or entity, any claim
         or portion thereof or interest therein. Executive agrees to indemnify,
         defend and hold Premcor harmless for any damages, costs, fees or
         expenses that it may incur if these representations and warranties are
         incorrect in any respect.

18)      Severability. If any provisions or part thereof of this Agreement is
         declared invalid, illegal or unenforceable in any respect, the
         validity, legality or enforceability of the remaining provisions of
         this Agreement, and any other application thereof, shall not in any way
         be affected or impaired, and the Agreement shall be construed in all
         respects as if such invalid, illegal, or unenforceable provisions are
         omitted.

         IN WITNESS WHEREOF, the undersigned parties have executed this
Separation Agreement and General Release.

Premcor Inc.                                  Jeffry N. Quinn



By:     /s/ THOMAS D. O'MALLEY                /s/ JEFFRY N. QUINN
        ----------------------------------    ----------------------------------
        Thomas D. O'Malley

Its:    Chairman and
        Chief Executive Officer

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