**Exhibit 10.43****GUARANTY AGREEMENT**     THIS GUARANTY AGREEMENT (this Guaranty Agreement, together with the exhibits and scheduleshereto and all extensions, renewals, amendments, substitutions and replacements hereto and hereof,is hereinafter referred to as the “Guaranty Agreement”) is dated as of the 28th day ofSeptember, 2007, by Westmoreland Coal Company, a Delaware corporation (“WCC”) and eachperson or entity now or hereafter executing a guaranty assumption agreement in the form of Annex 1attached hereto (each of the foregoing being a “Guarantor” and collectively, the“Guarantors”) to and for the benefit of NRG Texas Power LLC, a Delaware limited liabilitycompany (together with its successors and assigns, the “Beneficiary”).**WITNESSETH**     WHEREAS, Texas Westmoreland Coal Co. (“TWCC”) has entered into that certain LigniteSupply Agreement dated as of the date hereof between TWCC and Beneficiary (the “SupplyAgreement”);     WHEREAS, TWCC is a direct or indirect subsidiary of the Guarantors; and     WHEREAS, it is a condition precedent under the Supply Agreement that WCC provide this GuarantyAgreement in favor of Beneficiary.**AGREEMENT**     NOW, THEREFORE, as inducement to the Beneficiary to enter into the Supply Agreement and forother good and valuable consideration, the receipt and sufficiency of which are herebyacknowledged, each of the Guarantors agrees as follows:     1. ***Defined Terms***. Capitalized terms used herein but not defined herein shall have the meaningascribed to them in the Supply Agreement.     2. ***Guaranty***. Each of the Guarantors unconditionally and irrevocably guarantees toBeneficiary, the full and punctual payment when due of all TWCC’s obligations under the SupplyAgreement to the extent arising from any event that would constitute a TWCC Event of Default (andincluding such obligations, liabilities, and indebtedness described above arising or accruing afterthe commencement of any bankruptcy, insolvency, reorganization, or similar proceeding with respectto TWCC, or any Guarantor or which would have not arisen or accrued but for the commencement ofsuch proceeding, even if the claim for such obligation, liability, or indebtedness is notenforceable or allowable in such proceeding) (all of the foregoing obligations, liabilities andindebtedness described in this Section 2, are referred to herein collectively as the“Guaranteed Obligations” and each as a “Guaranteed Obligation”). In the event of adefault in performance of any of the Guaranteed Obligations, Guarantor shall promptly pay andperform or cause to be paid and performed such Guaranteed Obligations upon receiving written noticeof such default from the Beneficiary.Signature Page to Guaranty Agreement
 

 
     3. ***Obligations Absolute and Unconditional***.     (a) This Guaranty is, to the maximum extent permitted by law, a primary obligation ofGuarantor and shall be irrevocable, absolute and unconditional and shall remain in fullforce and effect until such time as all Guaranteed Obligations shall have been absolutelyand completely discharged and performed.     (b) Notwithstanding the foregoing or any other provision in this Guaranty to thecontrary, (i) each Guarantor shall have the full benefit of all defenses (including anydefense of non-performance due to Force Majeure (as defined in the Supply Agreement)),setoffs, counterclaims, reductions, diminution or limitations available to TWCC pursuant toor arising from the Supply Agreement or otherwise, except for those arising out of (A) anylegal limitation, lack of authority, disability or incapacity of TWCC, or (B) anybankruptcy, insolvency, dissolution or liquidation of TWCC, or (C) any invalidity orillegality of the Supply Agreement due to the status of TWCC, and (ii) each Guarantor shallhave the full benefit of, and does not waive or relinquish its rights and remedies accordedunder, applicable statutes of limitation and repose.     4. ***Waiver***. To the maximum extent permitted by law, and except as expressly provided in thisGuaranty or rights of notice provided in the Supply Agreement, each of the Guarantors herebyexpressly waives: (a) notice of acceptance of this Guaranty by Beneficiary (which acceptance isconclusively presumed by delivery hereof to Beneficiary); (b) grace, demand, presentment andprotest with respect to the Guaranteed Obligations or to any instrument, Supply Agreement ordocument evidencing or creating same; (c) notice of grace, demand, presentment and protest; (d)notice of non-payment or other defaults, of intention to accelerate and of acceleration of theGuaranteed Obligations; and (e) the renewal, extension, amendment and/or modification of any of theterms and provisions of the Supply Agreement.     5. ***Ultimate Liability of the Guarantor***. This is a guaranty of payment and performance, andnot merely of collection, and Guarantor agrees that this Guaranty may be enforced by Beneficiarywithout resorting to or exhausting any other security, party (including, without limitation, TWCC),or collateral. Guarantor hereby expressly waives any right or claim to force Beneficiary toproceed first against TWCC or any other guarantor or any other party as to any of the GuaranteedObligations, and agrees that no delay or refusal (subject to applicable statutes of limitation andrepose) of Beneficiary to exercise any right or privilege which Beneficiary has or may have againstTWCC, arising from the Supply Agreement, shall operate to impair the liability of Guarantorhereunder.     6. ***Term of Guaranty Agreement***. This Guaranty shall remain in full force and effect until thelater of termination of the Supply Agreement and fulfillment by TWCC of its obligations under theSupply Agreement.     7. ***Reinstatement***. The Guaranteed Obligations shall be automatically reinstated if, and to theextent that, for any reason any payment by or on behalf of Guarantor in respect of the GuaranteedObligations is rescinded as required by law or judicial decision or must be otherwiserestored by any holder of any of the Guaranteed Obligations, whether as a result of anyproceedings in bankruptcy or reorganization, or otherwise.Signature Page to Guaranty Agreement
 

 
     8. ***Payment***. Guarantor agrees that all amounts payable by Guarantor to Beneficiary under thisGuaranty shall be paid free and clear of, and without deduction for, withholding on account oftaxes, levies, imposts, duties or other charges of whatever nature, other than based upon the netincome, gross receipts, assets or operations of Beneficiary, except as provided for in the SupplyAgreement. Beneficiary may apply any payments received from any source against that portion of theGuaranteed Obligations in such priority and fashion as Beneficiary may deem appropriate, except tothe extent required under the Supply Agreement.     9. ***Representations and Warranties*****.**Each Guarantor represents and warrants to Beneficiarythat:     (a) it is duly organized and validly existing under the laws of the jurisdiction of itsincorporation and has full power and legal right to execute and deliver this GuarantyAgreement and to perform, or cause to be performed, the provisions of this GuarantyAgreement on its part to be performed;     (b) its execution, delivery and performance of this Guaranty Agreement have been andremain duly authorized by all necessary corporate action and do not contravene any provisionof its certificate of incorporation or bylaws or any law, regulation or contractualrestriction binding on it or its assets;     (c) neither the execution and delivery of this Guaranty Agreement nor the performanceby Guarantor of the terms of this Guaranty Agreement (i) will conflict with or result in abreach, default or violation of (A) the charter or bylaws of Guarantor or (B) any materialcontract, permit or judgment to which Guarantor is a party or to which it is subject or bywhich any of its assets is bound, or (ii) will result in the creation of any lien on anymaterial asset of Guarantor;     (d) all consents, authorizations, approvals and clearances and notifications, reportsand registrations requisite for the due execution, delivery and performance of this GuarantyAgreement have been obtained from or, as the case may be, filed with the relevantgovernmental authorities having jurisdiction and remain in full force and effect and allconditions have been duly complied with and no other action by, and no notice to or filingwith, any governmental authority having jurisdiction is required for such execution,delivery or performance;     (e) this Guaranty Agreement constitutes a legal, valid and binding obligation ofGuarantor, enforceable against it in accordance with its terms, except (a) as limited byapplicable bankruptcy, insolvency, reorganization, moratorium or other laws of generalapplication affecting enforcement of creditors rights against Guarantor and (b) generalprinciples of equity that restrict the availability of equitable remedies; and     (f) The Guarantor has no intent (i) to file a voluntary petition under any chapter ofthe Bankruptcy Code, Title 11 U.S.C. or in any manner seek relief, protection,reorganization, liquidation, dissolution or similar relief for debtors under any otherstate, local, federal or other insolvency laws, either at the present time or at any timehereafter, (ii) directly or indirectly to cause any involuntary petition to be filed againsttheSignature Page to Guaranty Agreement
 

 
Guarantor or directly or indirectly to cause the Guarantor to become the subject of anyproceedings pursuant to any state, federal or other insolvency law providing for the reliefof debtors, either at the present time or at any time hereafter, or (iii) directly orindirectly to cause any interest of the Guarantor to become the property of any bankruptestate or the subject of any state, federal or other bankruptcy, dissolution, liquidation orinsolvency proceedings, either at the present time or at any time hereafter.     (g) Immediately after giving effect to the execution of this Guaranty Agreement, theGuarantor (i) is not and will not be insolvent, (ii) has and will have assets having a fairsalable value in excess of the amount required to pay its liabilities on its existing debtsas they become absolute and matured, and (iii) is not and will not be left with unreasonablysmall capital with which to engage in its anticipated business.     10. ***Subrogation***. Upon making any payment hereunder, Guarantor shall be subrogated to therights of Beneficiary against TWCC with respect to such payment; provided that Guarantor shall notenforce any right or receive any payment by way of subrogation until all of the GuaranteedObligations shall have been paid in full, and Beneficiary agrees to take such steps as Guarantormay reasonably request to implement such subrogation.     11. ***Assignment***. Neither this Guaranty Agreement nor any right hereunder may be assigned byGuarantor without the prior written consent of Beneficiary, and any attempt to do so will be void,except for assignments and transfers by operation of law. This Guaranty Agreement shall be bindingupon, and inure to the benefit of, the parties hereto and their respective successors and permittedassigns.     12. ***Cumulative Rights***. Except as otherwise set forth herein, all rights of Beneficiaryhereunder or otherwise arising under any documents executed in connection with the GuaranteedObligations are separate and cumulative and may be pursued separately, successively orconcurrently, or not pursued, without affecting or limiting any other right of Beneficiary andwithout affecting or impairing the liability of Guarantor.     13. ***Governing Law; Jurisdiction and Forum; Resolution of Issues***. This Guaranty Agreementshall be governed by and construed in accordance with the laws of the State of Delaware, withoutgiving effect to principles of conflicts of law that may be waived. Each party hereto irrevocablysubmits to the non-exclusive jurisdiction of any Texas state court or any federal court sitting inthe State of Delaware in any action arising out of or relating to this Guaranty Agreement. Eachparty hereto hereby irrevocably waives, to the fullest extent it may effectively do so, the defenseof an inconvenient forum to the maintenance of such action or proceeding in such Delaware state orfederal court. Each party to this Guaranty Agreement irrevocably consents to service of process inthe manner provided for notices in Section 15 of this Guaranty Agreement. Nothing in thisGuaranty Agreement will affect the right of any party to this Guaranty Agreement to serve processin any other manner permitted by law. The parties hereto further agree, to the extent permitted bylaw, that final and unappealable judgment against any of them in any action or proceedingcontemplated above shall be conclusive and may be enforced in any other jurisdiction within oroutside the United States by suit on the judgment, a certified copy of which shall be conclusive evidence of the fact and amount of such judgment.Any arbitration conducted under the Supply Agreement shall include, if requested bySignature Page to Guaranty Agreement
 

 
Beneficiary, adetermination by the arbitrator(s) whether the payment obligation of TWCC thereunder constitutes aGuaranteed Obligation hereunder and the determination of such arbitrator(s) shall be binding on theGuarantors regardless of whether the Guarantors participated in the arbitration and without anyright of such Guarantors to appeal or obtain a reevaluation of such factual determination;provided, however, that Beneficiary will affirmatively consent to any request by Guarantor tointervene in any arbitration proceeding for the limited purpose of presenting arguments on theissue of whether an obligation of TWCC is a Guaranteed Obligation.     14. ***Integration of Terms***. This Guaranty Agreement contains the entire agreement betweenGuarantors and Beneficiary relating to the subject matter hereof and supersedes all oral statementsand prior writings with respect hereto. This Guaranty Agreement may not be amended, supplementedor modified, nor any terms and conditions hereof waived, except by a written instrument executed byGuarantors and Beneficiary.     15. ***Addresses***.     (a) Unless this Guaranty Agreement specifically requires otherwise, any notice, demand,process or request provided for in this Guaranty Agreement, or served, given or made inconnection with it, shall be in writing and shall be deemed properly served, given or madeif delivered in person or sent by facsimile or sent by registered or certified mail, postageprepaid and return receipt requested, or by a nationally recognized overnight courierservice that provides a receipt of delivery, in each case, to the parties at the addressesspecified below:If to Beneficiary:NRG Texas Power LLC