EXECUTIVE EMPLOYMENT AGREEMENT

        THISAGREEMENT executed as of the 28th day of February, 2001, by and between FrontierOil Corporation, a Wyoming corporation (the “Company”), and Nancy J. Zupan (the “Executive”). 

**W I T N E S S E T H:**

                WHEREAS the Executive is a principal officer of the Company and an integral part of itsmanagement;

        WHEREAS,the Company wishes to assure both itself and the Executive of continuity ofmanagement in the event of any actual or threatened change in control of theCompany; 

        WHEREAS,this Agreement is not intended to alter materially the compensation and benefitsthat the Executive could reasonably expect in the absence of a change in controlof the Company and, accordingly, this Agreement will be operative only upon achange in control of the Company, or if the Executive’s employment isterminated in anticipation of a change in control as that term is hereafterdefined. 

        NOWTHEREFORE, in consideration of the premises and covenants herein contained andother good, valuable and binding consideration, the receipt and sufficiency ofwhich are hereby acknowledged, it is hereby agreed by and between the parties asfollows: 

**              1.          Operation of Agreement.**

               1.01        This Agreement shall be binding immediately upon its execution by the parties hereto,but, notwithstanding anything in this Agreement to the contrary, the day prior to the date of a Change inControl of the Company or the day on which the Executive's employment is terminated in anticipation of achange in control as defined in paragraph 1.02 below shall be the operative date on which the Agreement andany provision thereof shall be operative and effective (the earlier to occur of such days shall be the "EffectiveDate").  Upon the Effective Date this Agreement and all provisions thereof shall become operative immediately,without the necessity of any further action on the part of either party hereto.

                                          The term of this Agreement shall end on the third anniversary of the date of executionof this Agreement; provided, however, that commencing on the date one year after the date hereof, and oneach annual anniversary of such date (such date and each annual anniversarythereof is hereinafter referred to as the “Renewal Date”), the term ofthis Agreement shall be automatically extended so as to terminate three yearsfrom such Renewal Date, unless at least thirty (30) days prior to the RenewalDate the Company shall give written notice that the term of the Agreement shallnot be so extended; and provided, further, that after a Change in Control of theCompany during the term of this Agreement, this Agreement shall remain in effectuntil three years after the Change in Control or until all of the obligations ofthe parties hereunder are satisfied, whichever occurs later.

                       1.02        For the purpose of this Agreement, the term "Change in Control of the Company" shallmean a change in control of a nature that would be required to be disclosed in a proxy statement, governed bythe rules of the Securities and Exchange Commission as in effect on the date of this Agreement; provided thatwithout limitation, such a change in control shall be deemed to have occurred upon the occurrence of any oneof the following:

                                          (a)         the consummation of any transaction (including without limitation, anymerger, consolidation,tender offer, or exchange offer) the result of which is that any individual or“person” (as such term is used in Sections 13(d)(3) and 14(d)(2), ofthe Securities Exchange Act of 1934 - the “Exchange Act”) is orbecomes the “beneficial owner” (as such term is defined in Rule 13d-3and Rule 13d-5 under the Exchange Act), directly or indirectly, of securities ofthe Company representing 25% or more of the combined voting power of theCompany’s then outstanding securities,

                                          (b)         the first day during any period of 24 consecutive months, commencing beforeor after the date of thisAgreement that the individuals, who at the beginning of such 24 month periodwere directors of the Company for whom the Executive shall have voted, cease forany reason to constitute at least a majority of the Board of Directors of theCompany,

                                          (c)         the sale, lease, transfer, conveyance or other disposition (including by mergeror consolidation) in one or a series of related transactions, of all or substantially all of the assets of theCompany and its Subsidiaries, taken as a whole,

                                          (d)         the adoption of a plan relating to the liquidation or dissolution of theCompany, or

                                          (e)         the date the Company files a report or proxy statement with the SEC statingthat a change in control has or may occur pursuant to any then existing contract or termination.

           1.03        This Agreement shall terminate forthwith, and without more, in the event thatExecutive ceases to be an executive officer of the Company at any time prior to the Effective Date whether byreason of his death, Disability, discharge, resignation or otherwise; except that either party wishing to terminatethe employment relationship, other than by reason of death, Disability or discharge for Cause, hereby agreesto give the other party at least 60 days prior written notice. Notwithstanding the foregoing, following thecommencement of any discussions of any third party that ultimately result in the occurrence of a Change ofControl, the Company shall not at the instance or upon the suggestion of such third party terminate theemployment or reduce the compensation of Executive.

                       1.04        Except as provided in paragraph 1.03 above, nothing expressed or implied herein shallcreate any right or duty (on the part of the Company or Executive) to have Executive remain in the employmentof the Company at any time prior to the Effective Date, each reserving all rights to terminate the employmentrelationship at any time (subject to the notice requirement contained in paragraph 1.03 above) prior to theEffective Date, with or without Cause.

     **2.           Employment; Period of Employment.**

                       2.01       The Company hereby agrees to continue the Executive in its employ, and theExecutive hereby agrees to remain in the employ of the Company, or subject to the terms of this Agreement,such other corporate profit center as shall then be the principal successor to the business, assets and theproperties of the Company, for the period set forth in paragraph 2.02 below (the "Period of Employment") inthe position and with the duties and responsibilities set forth in Section 3 below, and upon the other terms andconditions hereinafter stated.

                       2.02       The Period of Employment, subject only to the provisions of Section 6 below relatingto Disability, shall continue for a period of three years from the Effective Date.

     **3.          Position, Duties, Responsibilities.**

                       3.01        It is contemplated that at all times during the Period of Employment the Executiveshall continue to serve as a principal officer of the Company with the office and title of Vice President,General Counsel of the Company and continue to have duties and responsibilities commensurate with thoseduties and responsibilities imposed on the Executive immediately prior to the Effective Date.

                       3.02        During the Period of Employment the Executive shall also serve and continue to serve,if and when elected and reelected, as an officer or director, or both, of any subsidiary, division or affiliate ofthe Company.

                       3.03        Throughout the Period of Employment the Executive shall devote his full time andundivided attention during normal business hours to the business and affairs of the Company, except forreasonable vacations and except for illness or incapacity, but nothing in this Agreement shall preclude theExecutive from devoting reasonable periods required for serving as a director or member of a committee of anyorganization involving no conflict of interest with the interests of the Company, from engaging in charitableand community activities, and from managing his personal investments, provided that such activities do notmaterially interfere with the regular performance of his duties and responsibilities under this Agreement.

                       3.04        The office of the Executive shall be located at the executive offices of the Companyat 5340 S. Quebec Street, Suite 200N, Greenwood Village, Colorado 80111-1911.  The Executive shall not be required to changethe current situs of his employment or residence.  The Executive also shall not be required to be absenttherefrom on travel status or otherwise more than a total of 60 working days in any calendar year nor more than20 consecutive days at any one time.

     **4.          Compensation, Compensation Plans, Perquisites.**

                       4.01  (a)   For all services rendered by the Executive in any capacity during the Period ofEmployment, including, without limitation, services as an executive, officer, director or member of anycommittee of the Company or of any subsidiary, division or affiliate thereof, the Executive shall be paid ascompensation:

                   (i)   A base salary at no less than the rate in effect immediately prior to theEffective Date, with increases (if any) as shall be made from time to time inaccordance with the Employer’s regular salary administration practices;

                   (ii)   An annual performance bonus in an amount no less than the amount of 40% of thebase salary determined pursuant to subparagraph 4.01 (a)(i).

                                       (b)   Any increase in salary pursuant to clause (i) of subparagraph 4.01 (a) or in bonusor other compensation shallin no way diminish any other obligation of the Company under this Agreement.

                       4.02        During the Period of Employment the Executive shall be and continue to be a fullparticipant in the Company's applicable stock option plans and any other compensation plans in which theExecutive participates immediately prior to the Effective Date, or equivalent successor plans that may beadopted by the Company, with at least the same reward opportunities to Executive that have heretofore beenprovided. Nothing in this Agreement shall preclude improvement of reward opportunities in such plans or otherplans in accordance with the present practice of the Company.

                       4.03        During the Period of Employment, the Executive shall be entitled to perquisites,including, without limitation, an office, secretarial and clerical staff, and to fringe benefits, including, withoutlimitation, the payment or reimbursement of club dues, in each case at least equal to those attached to his officeimmediately prior to the Effective Date, as well as to reimbursement, upon proper accounting, of reasonableexpenses and disbursements incurred by him in the course of his duties.

     **5.          Employee Benefit Plans.**

                       5.01        The compensation, together with other matters provided for in Section 4 above, is inaddition to the benefits provided for in this Section 5.

                       5.02        The Executive, his dependents and beneficiaries shall be entitled to all payments andbenefits and service credit, for benefits during the Period of Employment to which officers of the Company,their dependents and beneficiaries are entitled as a result of the employment of such officers under the termsof employee plans and practices of the Company in effect immediately prior to the Effective Date, including,without limitation, the Company's retirement program (consisting of the Frontier Retirement Savings Plan, andthe Frontier Deferred Compensation Plan), the Company's stock purchase and savings, thrift and investmentplans, if any, the Frontier Oil Corporation Executive Life Insurance Plan, its group life insurance plans, itsaccidental death and dismemberment insurance, its business travel insurance, its long term disability, medical,dental and health and welfare plans and other present or successor plans and practices of the Company, itssubsidiaries and divisions, for which officers, their dependents and beneficiaries are eligible, and to allpayments or other benefits under any such plan or practice after the Period of Employment as a result ofparticipation in such plan or practice during the Period of Employment.

                       5.03        Nothing in this Agreement shall preclude the Company from amending or terminatingany employee benefit plan or practice but, it being the intent of the parties that the Executive shall continue tobe entitled during the Period of Employment to perquisites as set forth in paragraph 4.03 above and to benefitsand service credit for benefits under paragraph 5.02 above at least equal to those attached to his positionimmediately prior to the Effective Date, and nothing in this Agreement shall operate as, or be construed toreduce or authorize reduction without the Executive's written consent in the level of such perquisites, benefitsor service credit for benefits. In the event of any such reduction by amendment or termination of any plan orpractice or otherwise, the Executive, his dependents and beneficiaries shall continue to be entitled to perquisites,benefits and service credit for benefits under such plans or practices that he or his dependents and beneficiarieswould have received if such reduction had not taken place.

     **6.          Effect of Death or Disability.**

                       6.01        In the event of the death of the Executive during the Period of Employment, the legalrepresentative of the Executive shall be entitled to the compensation provided for in paragraph 4.01 during thebalance of the Period of Employment. The Period of Employment shall be deemed to have ended as of the closeof business on the last day ofthe twelfth month following the month in which death shall have occurred butwithout prejudice to any other payments due in respect of the Executive’sdeath hereunder or pursuant to any other agreements or arrangements with theCompany.

                       6.02        The term "Disability," as used in this Agreement, shall mean an illness or accidentwhich prevents the Executive from performing his duties under this Agreement for a period of six consecutivemonths. In the event of the Disability of the Executive during the Period of Employment, the Executive shallbe entitled to the full compensation provided for in this Agreement for the period of such Disability (i.e.,commencing on the date on which the Disability occurred) but not in excess of six months.  The Period ofEmployment shall be deemed to have ended as of the close of business on the last day of such six months'period but without prejudice to any payments due to the Executive in respect of disability or any short termillness or accident which prevents the Executive from performing his duties for a period of less than six months.

     **7.          Termination.**

                       7.01        In the event of a Termination, as defined in paragraph 7.03 below, during the Periodof Employment, the provisions of this Section 7 shall apply.

                       7.02        In the event of a Termination the Company shall, as liquidated damages or severancepay, or both, pay to the Executive and provide him, his dependents, beneficiaries and estate, with the following:

                                           (a)         The Company shall continue to pay the Executive the base salarycompensation provided inparagraph 4.01 (a)(i) above at the rate in effect at the time of Termination(which in accordance with the terms of this Agreement shall be no less than therate of base salary in effect immediately prior to the Effective Date). Suchbase salary shall be paid no less than monthly beginning at the end of the monthin which Termination occurred and continuing each month during the three (3)year period following Termination.

                                           (b)         The Company shall also continue to pay the Executive the annual performancebonus provided in paragraph4.01(a)(ii) above. Such annual performance bonus compensation shall be paid onan annual basis, so that a payment will be made in each of the three yearsfollowing Termination.

                                           (c)        With regard to the employee benefits and perquisites described in paragraphs5.02 and 4.03, the Companyshall pay the Executive an amount no less than 30% of the total amount of theunpaid base salary payable pursuant to subparagraph (a) above.

                                           (d)          In the event that the Executive shall at the time of Termination hold anoutstanding and unexercised(whether or not exercisable at the time) option or options theretofore grantedby the Company, the Company shall, in addition to the amounts provided forabove, pay to the Executive in a lump sum an amount equal to the excess abovethe option price under each such option of the Fair Market Value at the time ofTermination of the shares subject to each such option. Solely for the purpose ofthis subparagraph (d), Fair Market Value at the time of Termination shall bedeemed to mean the higher of (i) the average of the reported closing prices ofthe Common Shares of the Company, as reported on the New York Stock Exchange -Composite Transactions, on the last trading day prior to the Termination and onthe last trading day of each of the two preceding thirty-day periods, and (ii)in the event that a Change in Control, as defined in paragraph 1.02 above, priorto Termination shall have taken place as the result of a tender offer and suchChange in Control was consummated within twelve months of Termination, the pricepaid for a majority of the Common Shares of the Company in the course of such tender offer.

                                           (e)         At the Company's option, upon Termination the Company may pay Executivethe total of all amountspayable to Executive pursuant to subparagraphs (a), (b) and (c) of this Section7.02 in a lump sum payment. Executive may also elect upon Termination, toreceive all amounts payable to him pursuant to subparagraphs (a), (b) and (c) ofthis Section 7.02 in a lump sum payment by providing written notice of suchelection to the Company. The Company agrees to make a lump sum payment of thetotal of such amounts within 30 days of Executive’s notice of election toreceive lump sum payment. It is acknowledged and agreed that no lump sum paymentwill modify or obviate any obligations of the Company other than the paymentsotherwise due following Termination pursuant to subparagraphs (a), (b) and (c)above.

              7.03        The word "Termination," for the purpose of this Section 7 and any other provisions of thisAgreement, shall mean:

                                  (a)         Termination by the Company of the employment of the Executive by the Companyand its subsidiaries for any reason other than for Cause as defined in paragraph 7.04 below or for Disabilityas defined in subparagraph 6.02 above; or

                                  (b)         Termination by the Executive of his employment by the Company and its subsidiariesupon the occurrence of any of the following events:

                                                   (i)          Failure to elect or reelect the Executive to, or removal of the Executive from,the office set forth in paragraph 3.01 above.

                                                   (ii)        A significant change in the nature or scope of the authorities, powers,functions or duties ofExecutive as contemplated by paragraph 3.01 above, or a reduction incompensation, and such change and/or reduction is not remedied within 30 daysafter receipt by the Company of written notice from the Executive. 

                                                   (iii)      A determination by the Executive made in good faith that as a result of aChange in Control of theCompany, as defined in paragraph 1.02 above, and a change in circumstancesthereafter that significantly affects his position, he is unable to carry outthe authorities, powers, functions or duties attached to his position ascontemplated by Section 3 of this Agreement, and such determination is notremedied within 30 days after receipt by the Company of written notice from theExecutive.

                                                   (iv)        A breach by the Company of any provision of this Agreement not embracedwithin the foregoing clauses (i), (ii) and (iii) of this subparagraph 7.03(b) that is not remediedwithin 30 days after receipt by the Company of written notice from the Executive.

                                                   (v)         The liquidation, dissolution, consolidation or merger of the Company ortransfer of all orsubstantially all of the assets of the Company and its Subsidiaries unless asuccessor or successors (by merger, consolidation or otherwise) to which all ora significant portion of the assets have been transferred shall have assumed allduties and obligations of the Company under this Agreement.

        Anelection by the Executive to terminate his employment given under the provisionsof this paragraph 7.03 shall not be deemed a voluntary termination of employmentby the Executive for the purpose of this Agreement or any plan or practice ofthe Company. 

                       7.04        For the purpose of any provision of this Agreement, the termination of the Executive'semployment shall be deemed to have been for "Cause" only if:

                                           (a)         termination of his employment shall have been the result of an act or acts ofdishonesty on the part ofthe Executive constituting a felony and resulting or intended to result directlyor indirectly in gain or personal enrichment at the expense of the Company; or

                                           (b)          there has been a breach by the Executive during the Period of Employmentof the provisions ofparagraph 3.03 above, relating to the time to be devoted to the affairs of theCompany, or of Section 8.01, relating to confidential information, and suchbreach results in demonstrably material injury to the Company and with respectto any alleged breach of paragraph 3.03 or of section 8.01 hereof, the Executiveafter notice and an opportunity to be heard either shall have failed to remedysuch alleged breach or shall have failed to take all reasonable steps to thatend within thirty days from his receipt of written notice by the Companypursuant to resolution duly adopted by the Board of Directors of the Company;and provided that thereafter

                                           (c)         there shall have been delivered to the Executive a certified copy of a resolutionof the Board of Directorsof the Company adopted by the affirmative vote of not less than three-fourths ofthe entire membership of the Board of Directors called and held for that purposeand at which the Executive was given an opportunity to be heard, finding thatthe Executive was guilty of conduct set forth in subparagraphs (a) or (b) above,specifying the particulars thereof in detail.

        Anythingin this paragraph 7.04 or elsewhere in this Agreement to the contrarynotwithstanding, the employment of the Executive shall in no event be consideredto have been terminated by the Company for Cause if termination of hisemployment took place (a) as the result of bad judgment or negligence on thepart of the Executive, or (b) as the result of an act or omission without intentof gaining therefrom directly or indirectly a profit to which the Executive wasnot legally entitled, or (c) because of an act or omission believed by theExecutive in good faith to have been in or not opposed to the interest of theCompany, or (d) for any act or omission in respect of which a determinationcould properly be made that the Executive met the applicable standard of conductprescribed for indemnification or reimbursement or payment of expenses under thePolicies of the Company or the laws of the State of Wyoming or thedirectors’ and officers’ liability insurance of the Company, in eachcase as in effect at the time of such act or omission, or (e) as the result ofan act or omission which occurred more than twelve calendar months prior to theExecutive’s having been given notice of the termination of his employmentfor such act or omission unless the commission of such act or such omissioncould not at the time of such commission or omission have been known to a memberof the Board of Directors of the Company (other than the executive, if he isthen a member of the Board of Directors), in which case more than twelvecalendar months from the date that the commission of such act or such omissionwas or could reasonably have been so known, or (f) as the result of a continuingcourse of action which commenced and was or could reasonably have been known toa member of the Board of Directors of the Company (other than the Executive)more than twelve calendar months prior to notice having been given to theExecutive of the termination of his employment.

                       7.05        In the event that the Executive's employment shall be terminated by the Companyduring the Period of Employment and such termination is alleged to be for Cause, or the Executive's right toterminate his employment under paragraph 7.03(b) above shall be questioned by the Company or for any otherreason, the Executive shall have the right, in addition to all other rights and remedies provided by law, at hiselection either to seek arbitration in Harris County, Texas under the rules of the American ArbitrationAssociation by serving anotice to arbitrate upon the Company or to institute a judicial proceeding, ineither case within ninety days after having received notice of termination ofhis employment under paragraph 7.03(b) is subject to question or that theCompany is withholding or proposes to withhold payments or provision of benefitsor within such longer period as may reasonably be necessary for the Executive totake action in the event that his illness or incapacity should preclude histaking such action within such ninety-day period.

     **8.          Confidential Information**

                       8.01        The Executive agrees not to disclose, either while in the Company's employ or at anytime thereafter, to any person not employed by the Company, or not engaged to render services to the Company,any confidential information obtained by him while in the employ of the Company, including, withoutlimitation, any of the Company's inventions, processes, methods of distribution or customers or trade secrets;provided, however, that this provision shall not preclude the Executive from use or disclosure of informationknown generally to the public or of information not considered confidential by persons engaged in the businessconducted by the Company or from disclosure required by law or Court order.

                       8.02        The Executive also agrees that upon leaving the Company's employ he will not takewith him, without the prior written consent of an officer authorized to act in the matter by the Board ofDirectors of the Company, any drawing, blueprint, specification or other document of the Company, itssubsidiaries, affiliates and divisions, which is of a confidential nature relating to the Company, its subsidiaries,affiliates and divisions, or without limitation, relating to its or their methods of distribution, or any descriptionof any formulae or secret processes.

       **9.          Notices**

                       All notices, requests, demands and other communications provided for by this Agreement shallbe deemed to have been duly given if and when mailed in the continental United States by registered or certifiedmail, return receipt requested, postage prepaid, or personally delivered or sent by telex or other telegraphicmeans to the party entitled thereto at the address stated below or to such changed address as the addressee mayhave given by a similar notice: