MASTER AMENDMENT AND WAIVER AGREEMENT

Exhibit 10

MASTER AMENDMENT AND WAIVER AGREEMENT

     This MASTER AMENDMENT AND WAIVER AGREEMENT , dated as of March 28, 2008 (this “ Agreement ”), is by and among Heartland Grain Fuels, L.P., a Delaware limited partnership (the “ Borrower ”), each of the Lenders party hereto, WESTLB AG, NEW YORK BRANCH, as Administrative Agent for the Lenders, WESTLB AG, NEW YORK BRANCH, as Collateral Agent for the Senior Secured Parties, WESTLB AG, NEW YORK BRANCH, as Issuing Bank with respect to the Letters of Credit and AMARILLO NATIONAL BANK, in its capacity as Accounts Bank.

     WHEREAS, pursuant to the Senior Credit Agreement, dated as of October 1, 2007 (as further amended, restated, supplemented or otherwise modified from time to time, the “ Credit Agreement ”), among the Borrower, each of the Lenders from time to time party thereto, WestLB AG, New York Branch, as the Administrative Agent for the Lenders (the “ Administrative Agent ”), WestLB AG, New York Branch, as Collateral Agent for the Senior Secured Parties (the “ Collateral Agent ”), WestLB AG, New York Branch, As Issuing Bank with respect to the Letters of Credit and WestLB AG, New York Branch, as lead arranger, sole bookrunner and syndication agent, the Lenders agreed to make a credit facility available to the Borrower, subject to the terms and conditions set forth therein;

     WHEREAS, pursuant to a letter to the Administrative Agent dated February 1, 2008 and attached hereto as Schedule 1 (the “ Amendment Request Letter ”), the Borrower has informed the Administrative Agent that certain work in connection with the construction of the Project cannot be undertaken until after the Conversion Date Certain (the “ Spring Work ”), and that failure to complete the Spring Work before the Conversion Date Certain will not affect the normal operation of the Aberdeen II Plant or the Project;

     WHEREAS, the Borrower has requested, also pursuant to the Amendment Request Letter, that the Credit Agreement and the Accounts Agreement, dated as of October 1, 2007 (the “ Accounts Agreement ”), among the Borrower, Amarillo National Bank, as the Accounts Bank and the Securities Intermediary (the “ Accounts Bank ”), the Collateral Agent, the Administrative Agent, Wells Fargo Bank, National Association, in its capacity as trustee of the Brown County, South Dakota Subordinate Solid Waste Facilities Revenue Bonds (Heartland Grain Fuels, L.P. Ethanol Plant Project) Series 2007A for the Second Lien Claimholders, be amended as necessary to permit Project Costs associated with the Spring Work to be paid after the Conversion Date Certain, and that the parties hereto consent to such amendments;

     WHEREAS, pursuant to a letter to the Administrative Agent dated March 27, 2008 and attached hereto as Schedule 2 (the “ Waiver Request Letter ”), the Borrower has requested that the Lenders, Administrative Agent and Collateral Agent waive certain provisions of the Credit Agreement as set forth therein;

     NOW, THEREFORE, in consideration of the premises and the mutual covenants contained in the Credit Agreement, the Accounts Agreement and herein, and other

good and valuable consideration the receipt and adequacy of which are hereby acknowledged, the parties hereto agree as follows:

1.		Definitions . Capitalized terms used but not otherwise defined herein shall have the same meanings assigned to them in the Credit Agreement.
2.		Amendments to the Credit Agreement .

(a)

Item (x) of the first sentence of Section 2.06(e) ( Funding of Loans ) of the Credit Agreement is amended to read as follows:

"(x) first, apply any amounts on deposit in or standing to the credit of the Construction Account (other than amounts in the Bond Proceeds Sub-Account and an amount equal to the lesser of $1,700,000 and one hundred fifty percent (150%) of the total Project Costs listed on Schedule 7.01(y) in respect of the Spring Work), and”

(b)

Priority second of Section 2.06(e) ( Funding of Loans ) of the Credit Agreement is amended to read in its entirety as follows:

"(ii) second , to the Borrower for the payment of any remaining Project Costs (other than Project Costs in respect of the Spring Work);”

(c)

Priority third of Section 2.06(e) ( Funding of Loans ) of the Credit Agreement is amended to read in its entirety as follows:

"(iii) third , for deposit into the Contingency Reserve Account in an amount such that the amounts on deposit therein are equal to the Contingency Reserve Required Amount; provided , if the Administrative Agent receives an irrevocable, standby letter of credit, issued by a bank that is acceptable to the Administrative Agent in its sole discretion, in favor of the Collateral Agent, and in form and substance satisfactory to the Administrative Agent and the Collateral Agent, with respect to the warranty obligations related to the Aberdeen II Plant in the amount of two million five hundred thousand Dollars ($2,500,000) (the “ LC Condition ”), then as a prepayment of the Working Capital Loans in accordance with Section 3.09(d)(ii) ( Optional Prepayment ) in the amount of two million five hundred thousand Dollars ($2,500,000);”

(d)

Priority fourth of Section 2.06(e) ( Funding of Loans ) of the Credit Agreement is amended to read in its entirety as follows:

"(iv) fourth , (i) if the LC Condition has been satisfied, then as a distribution to the Sponsor in an amount not to exceed two million six hundred forty-five thousand Dollars ($2,645,000) to repay the loan (including accrued interest) from the Design-Build Contractor to the

Sponsor or (ii) if the LC Condition has not been satisfied, then as a prepayment of the Working Capital Loans in accordance with Section 3.09(d)(ii) ( Optional Prepayment ) in the amount of two million six hundred forty-five thousand Dollars ($2,645,000);”

(e)

Section 2.08(c) ( Termination or Reduction of Commitments ) of the Credit Agreement is amended to read in its entirety as follows:

"(c) Unless all of the Working Capital Lenders agree otherwise in writing, if the Conversion Date does not occur on or before the Conversion Date Certain, all Working Capital Loan Commitments (other than the obligations to participate in the Issuing Bank’s liability under any Letter of Credit pursuant to Section 2.04(c) ( Letters of Credit )) shall be automatically and permanently terminated on the Conversion Date Certain.”

(f)

Section 2.08(f) ( Termination or Reduction of Commitments ) of the Credit Agreement is amended to read in its entirety as follows:

"(f) Any Working Capital Loan Commitments (other than the obligations to participate in the Issuing Bank’s liability under any Letter of Credit pursuant to Section 2.04(c) ( Letters of Credit )) shall be automatically and permanently terminated in full and the Borrower shall be required to deposit in the LC Cash Collateral Sub-Account the aggregate Maximum Available Amounts under all issued and outstanding Letters of Credit on the earlier of (i) the date that is ninety (90) days after the date on which all outstanding Construction Loans and Term Loans have been paid in full and (ii) the Final Maturity Date.”

(g)

Section 3.03(c) ( Repayment of Working Capital Loan Fundings ) of the Credit Agreement is amended to read in its entirety as follows:

"(c) Unless all of the Working Capital Lenders agree otherwise in writing, if the Conversion Date does not occur on or prior to the Conversion Date Certain, then on the Conversion Date Certain, (i) each outstanding Working Capital Loan shall become due and payable, (ii) all amounts in any Project Accounts shall be promptly applied to the Obligations then outstanding in accordance with Section 4.2 ( Application of Proceeds ) of the Intercreditor Agreement, (iii) the Borrower shall pay all accrued interest on and repay the entire remaining principal amount of all outstanding Working Capital Loans to the Administrative Agent, for the pro rata account of the Lenders (based on their respective Working Capital Loan Commitment Percentages), together with any and all Fees and other Obligations

owed to the Senior Secured Parties, and (iv) the Borrower shall be required to deposit in the LC Cash Collateral Sub-Account the aggregate Maximum Available Amounts under all issued and outstanding Letters of Credit.”

(h)

Section 6.03(k) ( Conditions to Term Loan Funding — Final Survey ) of the Credit Agreement is amended to read in its entirety as follows:

"(k) Final Survey . The Administrative Agent shall have received a satisfactory as-built Survey of the Project (i) that is final except in respect of the Spring Work, (ii) that demonstrates that the Project has all real property interests required by the Financing Documents and (iii) that shows no Liens other than Permitted Liens.”

(i)

Section 7.01 ( Affirmative Covenants ) of the Credit Agreement is amended to include the following new subsection (y):

"(y) Spring Work . The Borrower shall cause the following conditions to be satisfied on or prior to June 30, 2008, as certified by each of the Borrower and the Independent Engineer in a Spring Work Completion Certificate completed to the reasonable satisfaction of the Administrative Agent and dated and delivered no later than June 30, 2008:

	(i)		the Spring Work shall have been completed;
	(ii)		the Borrower shall have received final construction drawings for the Aberdeen II Plant;
	(iii)		all Project Costs in respect of the Spring Work shall have been fully paid and the Administrative Agent shall have received reasonably satisfactory evidence that there are no mechanic’s, workmen’s, materialmen’s or other similar Liens or other claims on any part of the Aberdeen II Plant, the relevant Site, or other assets relating to the work or services of such Plant provided by the Design-Build Contractor or any of their subcontractors; and
	(iv)		the Design-Build Contractor and each subcontractor for such Plant shall have provided all satisfactory Lien waivers in respect of the Spring Work; and
	(v)		an updated survey for the Aberdeen II Plant’s Site has been prepared and is in form and substance satisfactory to the Independent Engineer.”

(j)

Section 7.01 ( Affirmative Covenants ) of the Credit Agreement is amended to include the following new subsection (z):

"(z) Ethanol Marketing Agreement . On or before April 14, 2008 or such later date as approved in writing by the Administrative Agent in its sole discretion, the Borrower shall enter into an amendment to the Ethanol Marketing Agreement, in form and substance satisfactory to the Administrative Agent in its sole discretion, reflecting the terms and conditions of the “ Term Sheet ” (as defined in the Master Waiver and Amendment Agreement).”

(k)

Section 7.03 ( Reporting Requirements ) of the Credit Agreement is hereby amended to include the following new subsection (q):

"(q) Daily Cash Flow Forecasts . Unless otherwise agreed in writing by the Administrative Agent in its sole discretion, on the first Business Day of each week, the Borrower shall deliver to the Administrative Agent a Daily Cash Flow Forecast.”

(l)

Section 8.02 ( Action Upon Bankruptcy ) of the Credit Agreement is amended to read in its entirety as follows:

“Section 8.02 Action Upon Bankruptcy . If any Event of Default described in Section 8.01(i) ( Events of Default — Bankruptcy, Insolvency ) occurs with respect to the Borrower, any outstanding Construction Loan Commitments, Term Loan Commitments or Working Capital Loan Commitments (other than the obligations to participate in the Issuing Bank’s liability under any Letter of Credit pursuant to Section 2.04(c) ( Letters of Credit )) (if not theretofore terminated) shall automatically terminate. The outstanding principal amount of the outstanding Loans and all other Obligations shall automatically be and become immediately due and payable, and the Borrower shall be required to immediately deposit in the LC Cash Collateral Sub-Account the aggregate Maximum Available Amounts under all issued and outstanding Letters of Credit, without notice, demand or further act of the Administrative Agent, the Collateral Agent or any other Senior Secured Party.”

(m)

Section 8.03 ( Action Upon Other Event of Default ) of the Credit Agreement is amended to read in its entirety as follows:

“Section 8.03 Action Upon Other Event of Default . (a) If any other Event of Default occurs and is continuing for any reason, whether voluntary or involuntary, and is continuing, the Administrative Agent may, or upon the direction of the Required Lenders shall, by written

notice to the Borrower, declare all or any portion of the outstanding principal amount of the Loans and other Obligations to be due and payable and/or any outstanding Construction Loan Commitments, Term Loan Commitments or Working Capital Loan Commitments (other than the obligations to participate in the Issuing Bank’s liability under any Letter of Credit pursuant to Section 2.04(c) ( Letters of Credit )) (if not theretofore terminated) to be terminated, and/or the aggregate Maximum Available Amounts under all issued and outstanding Letters of Credit to be deposited into the LC Cash Collateral Sub-Account, whereupon the full unpaid amount of such Loans and other Obligations that has been declared due and payable shall be and become immediately due and payable and the aggregate Maximum Available Amounts under all issued and outstanding Letters of Credit shall be deposited into the LC Cash Collateral Sub-Account, without further notice, demand or presentment and/or, as the case may be, any outstanding Construction Loan Commitments, Term Loan Commitments or Working Capital Loan Commitments (other than the obligations to participate in the Issuing Bank’s liability under any Letter of Credit pursuant to Section 2.04(c) ( Letters of Credit )) shall terminate. During the continuance of an Event of Default, the Administrative Agent may, or upon the direction of the Required Lenders shall, instruct the Collateral Agent to exercise any or all remedies provided for under this Agreement or the other Financing Documents.”

	(n)		The Credit Agreement is amended to add the document attached hereto as Exhibit C as Schedule 7.01(y) ( Spring Work ) to the Credit Agreement.
	(o)		The definition of “Contingency Reserve Required Amount” in Exhibit A ( Definitions ) of the Credit Agreement is amended to replace the language in section (ii) with the following:

"(ii) on and after the Conversion Date, two million five hundred thousand Dollars ($2,500,000); provided , that if the LC Condition has occurred, then on and after the Conversion Date, zero Dollars ($0).”

(p)

Exhibit A ( Definitions ) of the Credit Agreement is amended to include the following new defined terms:

“ Daily Cash Flow Forecast ” means a forecast of daily cash inflows and outflows for the Borrower covering the sixty (60) day period immediately succeeding the delivery of such forecast.

“ Spring Work ” means the work described in Schedule 7.01(y) ( Spring Work ) .

“ Spring Work Completion Certificate ” means (a) a certificate of the Independent Engineer, in substantially the form of Exhibit U-1 , or (b) a certificate of the Borrower, in substantially the form of Exhibit U-2 , in each case confirming that the Spring Work has been completed in accordance with Section 7.01(y) ( Spring Work ) .

(q)

The definition of “Final Completion Date” in Exhibit A ( Definitions ) of the Credit Agreement is amended to read in its entirety as follows:

"“ Final Completion Date ” means, with respect to the Aberdeen II Plant, the date (which shall occur on or before the Conversion Date Certain) on which the following conditions have been satisfied, as certified by each of the Borrower and the Independent Engineer in a Final Completion Certificate completed to the reasonable satisfaction of the Administrative Agent:

	(i)		construction of such Plant shall have been completed (other than punch list items and the Spring Work) and such Plant shall be ready to grind corn and begin operation for its intended use as an ethanol production facility, and such Plant shall not have adversely impacted the ability of the Existing Plants to perform at or above levels included in the performance assumption for the Existing Plants in the Financial Model;
	(ii)		the Performance Test shall have been completed and shall have demonstrated that such Plant has achieved the Performance Criteria, while meeting air emissions requirements;
	(iii)		training shall have been completed for all required personnel for such Plant in accordance with the Design-Build Agreement;
	(iv)		the Borrower shall have received a plant operation manual and plant maintenance manual, associated documents, training manuals, final safety plans, and all materials and documents provided by the Design-Build Contractor and other manufacturers, suppliers and vendors for such Plant, and in each case, shall have been verified by the Independent Engineer;

	(v)		the Borrower shall have received construction drawings for such Plant reflecting all work (other than the Spring Work) as complete;
	(vi)		all construction costs for such Plant (other than Project Costs in respect of the Spring Work) shall have been fully paid and the Administrative Agent shall have received reasonably satisfactory evidence that there are no mechanic’s, workmen’s, materialmen’s or other similar Liens or other claims on any part of such Plant, the relevant Site, or other assets relating to the work or services of such Plant provided by the Design-Build Contractor or any of their subcontractors (other than, in each such case, in respect of the Spring Work);
	(vii)		the Design-Build Contractor and each subcontractor for such Plant shall have provided all satisfactory Lien waivers (other than Lien waivers in respect of the Spring Work and Lien waivers in respect of spare parts purchased by the Borrower);
	(viii)		all Necessary Project Approvals required to be obtained at such time with respect to such Plant shall have been obtained;
	(ix)		insurance required pursuant to Schedule 7.01(h) and, with respect to the Borrower, any Project Document shall be in place, as confirmed by the Insurance Consultant; and
	(x)		an updated survey for such Plant’s Site has been prepared and (other than in respect of the Spring Work) is in form and substance satisfactory to the Independent Engineer.”

(r)

The definition of “Project Costs” in Exhibit A ( Definitions ) of the Credit Agreement is amended to replace the language in the first sentence preceding the colon with the following:

"“ Project Costs ” means the following costs and expenses incurred (or, if in connection with any Spring Work, the lesser of $1,700,000 and one hundred fifty percent (150%) of the costs and expenses expected to be incurred) by the Borrower in connection with the Aberdeen II Plant prior to the Final Completion Date (or, if in connection with any Spring Work, on or prior to June 30, 2008) and set forth in the Construction Budget or otherwise approved in writing by the Required Lenders (in consultation with the Independent Engineer):”

(s)

The proviso in Section 7(b) ( Delivery of Additional Documents for Construction Loans ) of Exhibit F ( Form of Conversion Date Funding Notice ) of Credit Agreement is amended to read as follows:

“ provided , that no invoices are yet available for Project Costs (x) in respect of the Spring Work or (y) in an amount of up to $1,000,000 provided for in relevant Construction Budget, and with respect to which, in each case, amounts are requested in this Conversion Date Funding Notice for funding Construction Loans;

(t)

Section 7(c) ( Delivery of Additional Documents for Construction Loans ) of Exhibit F ( Form of Conversion Date Funding Notice ) of Credit Agreement is amended by inserting the following text after the phrase “conditional sworn Lien Waiver Statements”:

"(except with respect to the Spring Work)”

(u)

The respective paragraphs of Exhibit Q-1 ( Form of Independent Engineer’s Final Completion Certificate ) of the Credit Agreement are amended to read in their entirety as follows:

	“3.		Construction of the Facility has been completed (other than punch list items and the Spring Work) and the Facility is ready to grind corn and begin operation for its intended use as an ethanol production facility, and the Facility has not adversely impacted the ability of the Existing Plants to perform at or above levels included in the performance assumption for the Existing Plants in the Financial Model;”
	“7.		the Borrower has received construction drawings for the Facility reflecting all work (other than the Spring Work) as complete;”
	“8.		all construction costs for the Facility (other than Project Costs in respect of the Spring Work) have been fully paid and there are no mechanic’s, workmen’s, materialmen’s or other similar

			Liens or other claims on any part of the Facility, the Site for such Facility or other assets relating to the work or services of the Facility provided by the Design-Build Contractor or any of their subcontractors (other than, in each such case, in respect of the Spring Work), and the undersigned and the Administrative Agent have received reasonably satisfactory evidence thereof;”
	“9.		the Design-Build Contractor and each subcontractor for the Facility has provided all satisfactory Lien waivers (other than Lien waivers in respect of the Spring Work and Lien waivers in respect of spare parts purchased by the Borrower);”
	“11.		an updated survey for the Facility’s Site has been prepared and (other than in respect of the Spring Work) is in form and substance satisfactory to the undersigned; and”
	“12.		Owners Scope for the Facility (other than in respect of the Spring Work) has been completed.”

(v)

The respective paragraphs of Exhibit Q-2 ( Form of Borrower’s Final Completion Certificate ) of the Credit Agreement are amended to read in their entirety as follows:

	“3.		Construction of the Facility has been completed (other than punch list items and the Spring Work) and the Facility is ready to grind corn and begin operation for its intended use as an ethanol production facility, and the Facility has not adversely impacted the ability of the Existing Plants to perform at or above levels included in the performance assumption for the Existing Plants in the Financial Model;”
	“7.		the Borrower has received construction drawings for the Facility reflecting all work (other than the Spring Work) as complete;”
	“8.		all construction costs for the Facility (other than Project Costs in respect of the Spring Work) have been fully paid and there are no mechanic’s, workmen’s, materialmen’s or other similar Liens or other claims on any part of t