COLLATERAL ASSIGNMENT

THIS COLLATERAL ASSIGNMENT (“Assignment”), effective March 30, 2015, is made and
executed by and between Agrinatural Gas, LLC, a Delaware limited liability
company, having its principal place of business at 201 - 10th Street, P.O. Box
216, Heron Lake, Minnesota 56137 ("Assignor") and Heron Lake BioEnergy, LLC, a
Minnesota limited liability company, having its principal place of business at
91246 - 390th Ave., Heron Lake, Minnesota 56137 ("Assignee").
A.    Assignor and Assignee are parties to a Loan Agreement, Negotiable
Promissory Note and Security Agreement dated as of March 30, 2015 (as amended,
restated or otherwise modified from time to time, the “Credit Agreements”) under
which Assignee has agreed to extend certain financial accommodations to the
Assignor.
B.    As a condition to extending the credit facilities to Assignor under the
Credit Agreements, Assignee has required the execution of this Assignment by
Assignor.
AGREEMENT
Accordingly, in consideration of the foregoing, the parties agree as follows:
1.    Assignor does hereby collaterally grant, assign, transfer and set over
unto the Assignee all of its right, title and interest in and to the leases,
contracts and agreements described on Exhibit A annexed hereto (whether one or
more, as the same have been or may be amended, restated, extended or otherwise
modified from time to time, the “Contract” whether one or more), by and between
the Assignor and various landowners named therein. Assignor acknowledges and
agrees that it maintains full and complete copies of each said Contract at its
principal place of business.

2.    Assignor agrees that Assignee does not assume any of the obligations or
duties of Assignor under and with respect to the Contract unless and until
Assignee shall have given the Assignor and the landowner named in the Contract
written notice that it has affirmatively exercised its right to assume and
perform under the Contract following the occurrence and during the continuance
of an Event of Default under the Credit Agreements. In the event that the
Assignee does not personally undertake to perform under the Contract, Assignee
shall have no liability whatsoever for the performance of any of such
obligations or duties. For the purpose of performing under the Contract,
Assignee may assign the Contract, upon notice to Assignor and the landowner
named in the Contract and subject to the terms of the Contract, to an entity
that will own all or substantially all of the assets of the Assignor, but
without any requirement of Assignor’s consent.

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3.    Assignor represents and warrants there have been no prior assignments of
any Contract, that each Contract is a valid and enforceable agreement, that
neither Assignor nor any landowner named in each Contract is in default
thereunder, and that all covenants, conditions and agreements have been
performed as required therein, except those not due to be performed until after
the date hereof. Assignor agrees that no material change in the terms thereof
shall be valid without the prior written approval of the Assignee, which
approval shall not be unreasonably withheld. Assignor agrees not to assign,
sell, pledge, mortgage or otherwise transfer or encumber its interest in the
Contract so long as this Assignment is in effect, except as otherwise permitted
under the Credit Agreements.
4.    Subject to Paragraph 5 below, Assignor hereby irrevocably constitutes and
appoints the Assignee as attorney-in-fact to demand, receive and enforce the
Assignor’s rights with respect to the Contract, to make payments under the
Contract, if necessary, and to give appropriate receipt, releases and
satisfactions for and on behalf of and in the name of Assignor, at the option of
the Assignee, with the same force and effect as the Assignor could do if this
Assignment had not been made.
5.    This Assignment shall constitute an absolute and present collateral
assignment, provided that the Assignee shall have no right under this Assignment
to take any actions under Paragraph 4 of this Assignment or enforce the
provisions of the Contract until an Event of Default occurs under the Credit
Agreements. Upon the occurrence and during the continuation of any Event of
Default, the Assignee may, upon expiration of any applicable cure period and
without affecting any of its rights or remedies against the Assignor under any
other instrument, document, or agreement, exercise its rights under this
Assignment as the Assignor’s attorney-in-fact in any manner permitted by law.
6.    The Assignor hereby agrees to indemnify and hold the Assignee harmless
from and against any and all claims, demands, liabilities, losses, lawsuits,
judgments, and costs and expenses, including without limitation reasonable
attorneys’ fees, to which it may become exposed, or which it may incur, in
exercising any of its rights under this Assignment.
7.    This Assignment shall be binding upon the Assignor, its successors and
assigns, and shall inure to the benefit of the Assignee and its successors and
assigns.
8.    This Assignment can be waived, modified, amended, terminated or discharged
only explicitly in writing signed by the Assignee. A waiver signed by the
Assignee shall be effective only in a specific instance and for the specific
purpose given. Mere delay or failure to act shall not preclude the exercise or
enforcement of any of the Assignee’s rights or remedies hereunder. All rights
and remedies of the Assignee shall be cumulative and shall be exercised
singularly or concurrently, at the Assignee’s option, and the exercise or
enforcement of any one such right or remedy shall neither be a condition to nor
bar the exercise or enforcement of any other remedy.
9.    All capitalized terms used in this Assignment, but not otherwise defined
herein, shall have the meanings as set forth in the Credit Agreements.
10.    This Assignment may be executed in two or more counterparts, each of
which shall be deemed to be an original but all of which together shall
constitute one and the same instrument.

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11.    This Assignment shall be binding upon the parties hereto, their
successors and assigns and shall inure to the benefit of the Assignee and its
successors or assigns.

ASSIGNOR: Agrinatural Gas, LLC,     ASSIGNEE: Heron Lake BioEnergy, LLC,
a Delaware limited liability             a Minnesota limited liability
company                     company

By: /s/ John Sprangers                                    
Print Name: John Sprangers                            
Its.: CEO                                                         

By: /s/ Steve A. Christensen                           
Print Name: Steve A. Christensen                   
Its.: CEO/GM                                                  

By: /s/ Ann Tessier                                           
Print Name: Ann Tessier                                  
Its.: CFO                                                         

By: /s/ Stacie Schuler                                      
Print Name: Stacie Schuler                             
Its.: CFO                                                         

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EXHIBIT “A”
TO
COLLATERAL ASSIGNMENT

The following property constitutes the “Contract” assigned pursuant to that
certain Collateral Assignment dated and effective March 30, 2015:

1.
All of Assignor’s easements, easement agreements, and easement rights in which
Assignor is the holder, dominant tenant or has any other beneficial interest
whatsoever, whether now existing or hereafter acquired by Assignor, relating to
or involving real property located in Brown, Cottonwood, Jackson and Nobles
Counties, in the State of Minnesota, and in any such other counties in which
Assignor may acquire future easement rights, and in locations represented on
Attachment 1, pages 1 thru 12, to this Exhibit “A”.

2.
All of Assignor’s contracts and licenses of whatever type and nature and all
transportation service agreements of whatever type and nature. Such assignment
includes, but is not limited to, any and all pipeline and maintenance service
agreements and pipeline construction agreements.

[Remainder intentionally blank.]

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