Exhibit 10.21


FIFTH AMENDED AND RESTATED

IRREVOCABLE STANDBY LETTER OF CREDIT


Letter of Credit No. 1158


Date
of Issuance:    February 16, 2007


	
  Issuer:

  	
   

  	
  Home Federal Bank

  
	
   

  	
   

  	
  225 South Main Avenue

  
	
   

  	
   

  	
  Sioux Falls, SD 57104

  
	
   

  	
   

  	
   

  
	
  To:

  	
   

  	
  Northwestern Services Corporation

  
	
   

  	
   

  	
  125 S. Dakota Avenue, Suite 1100

  
	
   

  	
   

  	
  Sioux Falls, SD 57104-6403

  



 


This Fifth Amended and Restated Irrevocable Standby Letter of Credit
amends, restates and replaces that certain Fourth Amended and Restated
Irrevocable Standby  Letter of Credit
dated February 16, 2006 by Home Federal Bank (Letter of Credit No. 1158).


1.             Home Federal Bank (the “Bank”) hereby
establishes in favor of NorthWestern Services Corporation (“NSC,” successor by
merger to NorthWestern Energy Corporation) an Irrevocable Standby Letter of
Credit (the “Letter of Credit”) at the request and for the account of Great
Plains Ethanol, LLC, a South Dakota limited liability company (“Great Plains”),
whereby the Bank, subject to the terms and conditions contained herein,
authorizes NSC to draw on it at any time or times before the Expiration Date
(as defined below), by its draft (the “Draft”), in the form of Appendix 1
hereto, an amount up to an aggregate amount of $780,000.00, as set forth on an
accompanying certificate (the “Draw Certificate”), in the form of Appendix 2
hereto.


2.             This Letter of Credit shall expire at the
close of business on March 1, 2008 (the “Expiration Date”), unless extended.


3.             This Letter of Credit is issued in conjunction
with a Natural Gas Distribution Delivery Agreement between NorthWestern Energy
Corporation and Great Plains dated September 2, 2002 (the “Agreement”), under
which Great Plains agreed to transport a minimum quantity of natural gas to its
plant at a fixed price for delivery through a pipeline constructed to serve the
plant and the obligations of Great Plains













under the Agreement. The terms and conditions of the Agreement are
incorporated herein by reference.


4.             Funds under this Letter of Credit are available
to NSC in accordance with and against its Draft and Draw Certificate, each
dated the date of presentation and executed by an officer of NSC, referring to
the number of this Letter of Credit and presented along with the original
Letter of Credit at our office at 225 South Main Avenue, Sioux Falls, South
Dakota 57104 during normal banking hours on or prior to the Expiration Date or
any extension thereof. NSC warrants and represents to the Bank that it has
assigned or will assign its rights to the proceeds of this Letter of Credit to
Tetra Financial Group. Within 48 hours following presentation of the Draft,
Draw Certificate and original Letter of Credit, the funds drawn shall be
payable jointly by the Bank to NSC and Tetra Financial Group.


5.             This Letter of Credit sets forth in full the
terms of our undertaking, and such undertaking shall not in any way be modified
or amended, without the consent of the Bank, except as to the completion of the
Draft and Draw Certificates referred to herein.


	
   

  	
  HOME
  FEDERAL BANK

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By 

  	
  /s/ David Brown

  
	
   

  	
  Its 

  	
  Senior Vice President

  
	
   

  
	
   

  
	
  AGREED AND ACCEPTED

  
	
  this             
  day of February, 2007.

  
	
   

  
	
  NORTHWESTERN SERVICES CORPORATION

  
	
   

  
	
   

  
	
  By 

  	
  /s/ Paul Evans

  	
   

  
	
  Its 

  	
  Treasurer

  	
   

  
					



 



 2
 









Appendix 1


DRAFT


Date:


	
  To:

  	
   

  	
  Home Federal Bank

  
	
   

  	
   

  	
  225 South Main Avenue

  
	
   

  	
   

  	
  Sioux Falls, SD 57104

  



 


Within 48 hours of presentation of this Draft, a signed and completed
Draw Certificate and the original Letter of Credit, PAY JOINTLY TO THE ORDER OF
NorthWestern Services Corporation (successor by merger to NorthWestern Energy
Corporation) and Tetra Financial Group the sum of $                
under that certain Natural Gas Distribution Delivery Agreement between
NorthWestern Energy Corporation and Great Plains Ethanol, LLC dated September
2, 2002.


Drawn under Fifth Amended and Restated Irrevocable Standby Letter of
Credit No. 1158 dated February 16, 2007.


	
   

  	
  NORTHWESTERN SERVICES

  
	
   

  	
  CORPORATION

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By 

  	
   

  
	
   

  	
  Its 

  	
   

  



 



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Appendix 2


DRAW CERTIFICATE


Letter of Credit No. 1158


Date:


	
  To:

  	
   

  	
  Home Federal Bank

  
	
   

  	
   

  	
  225 South Main Avenue

  
	
   

  	
   

  	
  Sioux Falls, SD 57104

  



 


The undersigned, a duly authorized officer of NorthWestern Services
Corporation (“NSC,” successor by merger to NorthWestern Energy Corporation),
certifies to Home Federal Bank that:


1.             NSC is making a draw under the Fifth Amended
and Restated Irrevocable Standby Letter of Credit No. 1158 dated February 16,
2007 with respect to (check the applicable box):


o            a
failure by Great Plains to meet the Minimum Annual Obligation for 20    
established under the Natural Gas Distribution Delivery Agreement between
NorthWestern Energy Corporation and Great Plains dated September 2, 2002 (the
“Agreement”),


o            a
failure by Great Plains to meet the Minimum Total Obligation established under
the Agreement, or


o            the
termination of the Agreement by Great Plains for any reason other than for
NSC’s refusal to perform its obligations under the Agreement.


2.             The amount of the Draft accompanying this
Certificate is $                   ,
such sum being (check the applicable box):


o            the
remaining Minimum Annual Obligation for 20     , or


o            I
the entire outstanding balance of Great Plains’ Minimum Total Obligation



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in accordance with the terms
of the Agreement.


3.             The amount of the Draft accompanying this
Certificate was computed in accordance with the terms and conditions of the
Agreement and does not exceed, when combined with any prior amount drawn by
NSC, the amount available to be so drawn.


	
   

  	
  NORTHWESTERN SERVICES

  
	
   

  	
  CORPORATION

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By 

  	
   

  
	
   

  	
  Its 

  	
   

  



 



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