**Exhibit 10.23**CHANGE IN CONTROL AGREEMENT          THIS AGREEMENT, dated September 28, 2007, is made by and between US BioEnergy Corporation (the“Company”), and Gordon W. Ommen (the “Executive”).          WHEREAS, the Company considers it essential to the best interests of its stockholders tofoster the continued employment of key management personnel; and          WHEREAS, the Board recognizes that, as is the case with many publicly held corporations, thepossibility of a Change in Control exists and that such possibility, and the uncertainty andquestions which it may raise among management, may result in the departure or distraction ofmanagement personnel to the detriment of the Company and its stockholders; and          WHEREAS, the Board has determined that appropriate steps should be taken to reinforce andencourage the continued attention and dedication of members of the Company’s management, includingthe Executive, to their assigned duties without distraction in the face of potentially disturbingcircumstances arising from the possibility of a Change in Control;          NOW, THEREFORE, in consideration of the premises and the mutual covenants herein contained,the Company and the Executive hereby agree as follows:          1. Defined Terms. The definitions of capitalized terms used in this Agreement areprovided in the last Section hereof.          2. Term of Agreement. The Term of this Agreement shall commence on the date hereofand shall continue in effect through December 31, 2009; provided, however, thatcommencing on January 1, 2009 and each January 1 thereafter, the Term shall automatically beextended for one additional year unless, not later than September 30 of the preceding year, theCompany or the Executive shall have given notice not to extend the Term; and furtherprovided, however, that if a Change in Control shall have occurred during the Term,the Term shall expire no earlier than twenty-four (24) months beyond the month in which such Changein Control occurred.          3. Company’s Covenants Summarized. In order to induce the Executive to remain in theemploy of the Company and in consideration of the Executive’s covenants set forth in Section 4hereof, the Company agrees, under the conditions described herein, to pay the Executive theSeverance Payments and the other payments and benefits described herein. No Severance Paymentsshall be payable under this Agreement unless there shall have been (or, under the terms of thesecond sentence of Section 6.1 hereof, there shall be deemed to have been) a termination of theExecutive’s employment with the Company following a Change in Control and during the Term.
 

 
This Agreement shall not be construed as creating an express or implied contract of employmentand, except as otherwise agreed in writing between the Executive and the Company, the Executiveshall not have any right to be retained in the employ of the Company.          4. The Executive’s Covenants. The Executive agrees that, subject to the terms andconditions of this Agreement, in the event of a Potential Change in Control during the Term, theExecutive will remain in the employ of the Company until the earliest of (i) a date which is six(6) months from the date of such Potential Change in Control, (ii) the date of a Change in Control,(iii) the date of termination by the Executive of the Executive’s employment for Good Reason or byreason of death, Disability or Retirement, or (iv) the termination by the Company of theExecutive’s employment for any reason.          5. Compensation Other Than Severance Payments.          5.1 Following a Change in Control and during the Term, during any period that the Executivefails to perform the Executive’s full-time duties with the Company as a result of incapacity due tophysical or mental illness, the Company shall pay the Executive’s full salary to the Executive atthe rate in effect at the commencement of any such period, together with all compensation andbenefits payable to the Executive under the terms of any compensation or benefit plan, program orarrangement maintained by the Company during such period (other than any disability plan), untilthe Executive’s employment is terminated by the Company for Disability.          5.2 If the Executive’s employment shall be terminated for any reason following a Change inControl and during the Term, the Company shall pay the Executive’s full salary to the Executivethrough the Date of Termination at the rate in effect immediately prior to the Date of Terminationor, if higher, the rate in effect immediately prior to the first occurrence of an event orcircumstance constituting Good Reason, together with all compensation and benefits payable to theExecutive through the Date of Termination under the terms of the Company’s compensation and benefitplans, programs or arrangements as in effect immediately prior to the Date of Termination or, ifmore favorable to the Executive, as in effect immediately prior to the first occurrence of an eventor circumstance constituting Good Reason.          5.3 If the Executive’s employment shall be terminated for any reason following a Change inControl and during the Term, the Company shall pay to the Executive the Executive’s normalpost-termination compensation and benefits as such payments become due. Such post-terminationcompensation and benefits shall be determined under, and paid in accordance with, the Company’sretirement, insurance and other compensation or benefit plans, programs and arrangements as ineffect immediately prior to the Date of Termination or, if more favorable to the Executive, as ineffect immediately prior to the occurrence of the first event or circumstance constituting GoodReason; provided, however, that the Executive shall be entitled to a cash payment in respect of theExecutive’s accrued paid time off, calculated based on the Executive’s base
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salary in effect at the Date of Termination (without giving effect to any change theretoconstituting Good Reason).          5.4 Upon the occurrence of a Change in Control, all of the Executive’s then-outstandingoptions, restricted stock and other equity awards from the Company which vest based on continuedservice with the Company shall immediately vest. All of the Executive’s then-outstanding options,restricted stock and other equity awards which vest based on the achievement of specificperformance criteria will vest on a pro-rata basis to the extent that the performance criteria havebeen achieved as of the date of the Change in Control. If and to the extent actual performanceresults as of the Change in Control date cannot be determined at the time of the Change in Control,such performance-based equity awards will vest on a pro-rata basis as of the date of the Change inControl assuming performance at the target level was achieved.          6. Severance Payments.          6.1 Subject to Section 6.2 hereof, if the Executive’s employment is terminated during the twoyear period immediately following a Change in Control and during the Term, other than (A) by theCompany for Cause, (B) by reason of death or Disability, or (C) by the Executive without GoodReason, then the Company shall pay the Executive the amounts, and provide the Executive thebenefits, described in this Section 6.1 (“Severance Payments”), in addition to any payments andbenefits to which the Executive is entitled under Section 5 hereof. For purposes of thisAgreement, the Executive’s employment shall be deemed to have been terminated following a Change inControl by the Company without Cause or by the Executive with Good Reason, if within the 90 dayperiod prior to a Change in Control (i) the Executive’s employment is terminated by the Companywithout Cause and such termination was at the request or direction of a Person who has entered intoan agreement with the Company the consummation of which would constitute a Change in Control, (ii)the Executive terminates his employment for Good Reason prior to a Change in Control and thecircumstance or event which constitutes Good Reason occurs at the request or direction of suchPerson, or (iii) the Executive’s employment is terminated by the Company without Cause or by theExecutive for Good Reason and such termination or the circumstance or event which constitutes GoodReason is otherwise in connection with or in anticipation of a Change in Control.               (A) In lieu of any further salary payments to the Executive for periods subsequent tothe Date of Termination and in lieu of any severance benefit otherwise payable to theExecutive, the Company shall pay to the Executive a lump sum severance payment, in cash,equal to three times the sum of (i) the Executive’s base salary as in effect immediatelyprior to the Date of Termination or, if higher, in effect immediately prior to the firstoccurrence of an event or circumstance constituting Good Reason, and (ii) the greater of(1) the target annual bonus of the Executive pursuant to any annual bonus or incentive planmaintained by the Company in respect of the fiscal year in which occurs the Date ofTermination or (2) the annual bonus earned by the Executive pursuant to
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any annual bonus or incentive plan maintained by the Company with respect to thefiscal year ending immediately prior to the fiscal year in which occurs the Date ofTermination.               (B) For the thirty-six (36) month period immediately following the Date ofTermination, the Company shall arrange to provide the Executive and his dependents health,vision care and dental insurance benefits substantially similar to those provided to theExecutive and his dependents immediately prior to the Date of Termination or, if morefavorable to the Executive, those provided to the Executive and his dependents immediatelyprior to the first occurrence of an event or circumstance constituting Good Reason, at nogreater after tax cost to the Executive than the after tax cost to the Executiveimmediately prior to such date or occurrence; provided, however, that,unless the Executive consents to a different method, such health insurance benefits shallbe provided through a third-party insurer. Benefits otherwise receivable by the Executivepursuant to this Section 6.1(B) shall be reduced to the extent benefits of the same typeare received by or made available to the Executive by a subsequent employer during thethirty-six (36) month period following the Executive’s termination of employment (and anysuch benefits received by or made available to the Executive shall be reported to theCompany by the Executive).          6.2 (A) Notwithstanding any other provisions of this Agreement, in the event that any paymentor benefit received or to be received by the Executive (including any payment or benefit receivedin connection with a Change in Control or the termination of the Executive’s employment, whetherpursuant to the terms of this Agreement or any other plan, arrangement or agreement) (all suchpayments and benefits, including the Severance Payments, being hereinafter referred to as the“Total Payments”) would not be deductible (in whole or part), by the Company, an affiliate orPerson making such payment or providing such benefit as a result of section 280G of the Code, then,to the extent necessary to make such portion of the Total Payments deductible (and after takinginto account any reduction in the Total Payments provided by reason of section 280G of the Code insuch other plan, arrangement or agreement), the cash Severance Payments shall first be reduced (ifnecessary, to zero), and all other Severance Payments shall thereafter be reduced (if necessary, tozero); provided, however, that the Executive may elect to have the noncashSeverance Payments reduced (or eliminated) prior to any reduction of the cash Severance Payments.          (B) For purposes of this limitation, (i) no portion of the Total Payments the receipt orenjoyment of which the Executive shall have waived at such time and in such manner as not toconstitute a “payment” within the meaning of section 280G(b) of the Code shall be taken intoaccount, (ii) no portion of the Total Payments shall be taken into account which, in the opinion oftax counsel (“Tax Counsel”) reasonably acceptable to the Executive and selected by the accountingfirm which was, immediately prior to the Change in Control, the Company’s independent auditor (the“Auditor”), does not constitute a “parachute payment” within the meaning of section 280G(b)(2) ofthe Code, including by reason of section 280G(b)(4)(A) of the Code, (iii) the Severance Payments
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shall be reduced only to the extent necessary so that the Total Payments (other than thosereferred to in clauses (i) or (ii)) in their entirety constitute reasonable compensation forservices actually rendered within the meaning of section 280G(b)(4)(B) of the Code or are otherwisenot subject to disallowance as deductions by reason of section 280G of the Code, in the opinion ofTax Counsel, and (iv) the value of any noncash benefit or any deferred payment or benefit includedin the Total Payments shall be determined by the Auditor in accordance with the principles ofsections 280G(d)(3) and (4) of the Code.          (C) If it is established pursuant to a final determination of a court or an Internal RevenueService proceeding that, notwithstanding the good faith of the Executive and the Company inapplying the terms of this Section 6.2, the Total Payments paid to or for the Executive’s benefitare in an amount that would result in any portion of such Total Payments being subject to theExcise Tax, then, if such repayment would result in (i) no portion of the remaining Total Paymentsbeing subject to the Excise Tax and (ii) a dollar-for-dollar reduction in the Executive’s taxableincome and wages for purposes of federal, state and local income and employment taxes, theExecutive shall have an obligation to pay the Company upon demand an amount equal to the sum of (i)the excess of the Total Payments paid to or for the Executive’s benefit over the Total Paymentsthat could have been paid to or for the Executive’s benefit without any portion of such TotalPayments being subject to the Excise Tax; and (ii) interest on the amount set forth in clause (i)of this sentence at the rate provided in section 1274(b)(2)(B) of the Code from the date of theExecutive’s receipt of such excess until the date of such payment.          6.3 Subject to Section 14 hereof, the payments provided in subsection (A) of Section 6.1hereof shall be made not later than the fifth day following the Date of Termination. At the timethat payments are made under this Agreement, the Company shall provide the Executive with a writtenstatement setting forth the manner in which such payments were calculated and the basis for suchcalculations including, without limitation, any opinions or other advice the Company has receivedfrom Tax Counsel, the Auditor or other advisors or consultants (and any such opinions or advicewhich are in writing shall be attached to the statement).          6.4 The Company also shall pay to the Executive all legal fees and expenses incurred by theExecutive in disputing in good faith any issue hereunder relating to the termination of theExecutive’s employment, in seeking in good faith to obtain or enforce any benefit or right providedby this Agreement or in connection with any tax audit or proceeding to the extent attributable tothe application of section 4999 of the Code to any payment or benefit provided hereunder. Suchpayments shall be made within five (5) business days after delivery of the Executive’s writtenrequests for payment accompanied with such evidence of fees and expenses incurred as the Companyreasonably may require.          7. Termination Procedures and Compensation During Dispute.
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          7.1 Notice of Termination. After a Change in Control and during the Term, anypurported termination of the Executive’s employment (other than by reason of death) shall becommunicated by written Notice of Termination from one party hereto to the other party hereto inaccordance with Section 10 hereof. For purposes of this Agreement, a “Notice of Termination” shallmean a notice which shall indicate the specific termination provision in this Agreement relied uponand shall set forth in reasonable detail the facts and circumstances claimed to provide a basis fortermination of the Executive’s employment under the provision so indicated. Further, a Notice ofTermination for Cause is required to include a copy of a resolution duly adopted by the affirmativevote of not less than three-quarters (3/4) of the entire membership of the Board at a meeting ofthe Board which was called and held for the purpose of considering such termination (afterreasonable notice to the Executive and an opportunity for the Executive, together with theExecutive’s counsel, to be heard before the Board) finding that, in the good faith opinion of theBoard, the Executive was guilty of conduct set forth in clause (i) or (ii) of the definition ofCause herein, and specifying the particulars thereof in detail.          7.2 Date of Termination. “Date of Termination,” with respect to any purportedtermination of the Executive’s employment after a Change in Control and during the Term, shall mean(i) if the Executive’s employment is terminated for Disability, thirty (30) days after Notice ofTermination is given (provided that the Executive shall not have returned to the full-timeperformance of the Executive’s duties during such thirty (30) day period), and (ii) if theExecutive’s employment is terminated for any other reason, the date specified in the Notice ofTermination (which, in the case of a termination by the Company, shall not be less than thirty (30)days (except in the case of a termination for Cause) and, in the case of a termination by theExecutive, shall not be less than fifteen (15) days nor more than sixty (60) days, respectively,from the date such Notice of Termination is given).          7.3 Dispute Concerning Termination. If within fifteen (15) days after any Notice ofTermination is given, or, if later, prior to the Date of Termination (as determined without regardto this Section 7.3), the party receiving such Notice of Termination notifies the other party thata dispute exists concerning the termination, the Date of Termination shall be extended until theearlier of (i) the date on which the Term ends or (ii) the date on which the dispute is finallyresolved, either by mutual written agreement of the parties or by a final judgment, order or decreeof an arbitrator or a court of competent jurisdiction (which is not appealable or with respect towhich the time for appeal therefrom has expired and no appeal has been perfected);provided, however, that the Date of Termination shall be extended by a notice ofdispute given by the Executive only if such notice is given in good faith and the Executive pursuesthe resolution of such dispute with reasonable diligence.          7.4 Compensation During Dispute. If a purported termination occurs following a Changein Control and during the Term and the Date of Termination is extended in accordance with Section7.3 hereof, the Company shall continue to pay the Executive the full compensation in effect whenthe notice giving rise to the dispute was
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given (including, but not limited to, salary) and continue the Executive as a participant inall compensation, benefit and insurance plans in which the Executive was participating when thenotice giving rise to the dispute was given, until the Date of Termination, as determined inaccordance with Section 7.3 hereof. Amounts paid under this Section 7.4 are in addition to allother amounts due under this Agreement (other than those due under Section 5.2 hereof) and shallnot be offset against or reduce any other amounts due under this Agreement.          8. No Mitigation. The Company agrees that, if the Executive’s employment with theCompany terminates during the Term, the Executive is not required to seek other employment or toattempt in any way to reduce any amounts payable to the Executive by the Company pursuant toSection 6 hereof or Section 7.4 hereof. Further, except as specifically provided in Section 6.1(B)hereof, no payment or benefit provided for in this Agreement shall be reduced by any compensationearned by the Executive as the result of employment by another employer, by retirement benefits, byoffset against any amount claimed to be owed by the Executive to the Company, or otherwise.          9. Successors; Binding Agreement.          9.1 In addition to any obligations imposed by law upon any successor to the Company, theCompany will require any successor (whether direct or indirect, by purchase, merger, consolidationor otherwise) to all or substantially all of the business and/or assets of the Company to expresslyassume and agree to perform this Agreement in the same manner and to the same extent that theCompany would be required to perform it if no such succession had taken place.          9.2 This Agreement shall inure to the benefit of and be enforceable by the Executive’spersonal or legal representatives, executors, administrators, successors, heirs, distributees,devisees and legatees. If the Executive shall die while any amount would still be payable to theExecutive hereunder (other than amounts which, by their terms, terminate upon the death of theExecutive) if the Executive had continued to live, all such amounts, unless otherwise providedherein, shall be paid in accordance with the terms of this Agreement to the executors, personalrepresentatives or administrators of the Executive’s estate.          10. Notices. For the purpose of this Agreement, notices and all other communicationsprovided for in the Agreement shall be in writing and shall be deemed to have been duly given whendelivered or mailed by United States registered mail, return receipt requested, postage prepaid,addressed, if to the Executive, to the address inserted below the Executive’s signature on thefinal page hereof and, if to the Company, to the address set forth below, or to such other addressas either party may have furnished to the other in writing in accordance herewith, except thatnotice of change of address shall be effective only upon actual receipt:
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To the Company:US BioEnergy Corporation