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                          [FORM OF FACE OF CERTIFICATE]



                 Organized Under the Laws of the State of Kansas


                                                           CLASS D CAPITAL UNITS

D-

                          WESTERN PLAINS ENERGY, L.L.C.

THIS CERTIFIES THAT___________________________________________ IS THE OWNER AND
REGISTERED HOLDER OF______________________________________ CLASS D CAPITAL UNITS

                        in Western Plains Energy, L.L.C.

TRANSFERABLE ONLY ON THE BOOKS OF THE LIMITED LIABILITY COMPANY BY THE HOLDER
HEREOF IN PERSON OR BY DULY AUTHORIZED ATTORNEY UPON SURRENDER OF THIS
CERTIFICATE PROPERLY ENDORSED.

              IN WITNESS WHEREOF, THE SAID LIMITED LIABILITY COMPANY HAS CAUSED
              THIS CERTIFICATE TO BE SIGNED BY ITS DULY AUTHORIZED OFFICERS THIS
              _____ DAY OF _________, 200__.





           -------------------                    --------------------
                SECRETARY                               PRESIDENT


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                        [FORM OF REVERSE OF CERTIFICATE]

            The Capital Units represented by this Certificate have
            not been registered under the Securities Act of 1933, as
            amended. The sale and transfer of the Capital Units
            represented by this Certificate are restricted by, and
            subject to, the provisions of the Operating Agreement of
            Western Plains Energy, L.L.C. The Operating Agreement
            provides, among other things, that no sale, assignment,
            transfer, gift, exchange or other disposition of these
            Capital Units is valid except as specifically provided
            for in the Operating Agreement. Copies of the Operating
            Agreement and instructions for transfer, sale or other
            disposition of these Capital Units are available for
            inspection at the Company's principal office.

FOR VALUE RECEIVED __________ HEREBY SELL, ASSIGN AND TRANSFER
UNTO__________________________________________________________________________
_____________________________________________________ CAPITAL UNITS REPRESENTED
BY THE WITHIN CERTIFICATE, AND DO HEREBY IRREVOCABLY CONSTITUTE AND APPOINT
__________________ ____________________________________________________ ATTORNEY
TO TRANSFER THE SAID CAPITAL UNITS ON THE BOOKS OF THE WITHIN NAMED LIMITED
LIABILITY COMPANY WITH FULL POWER OF SUBSTITUTION IN THE PREMISES.

DATED ____________________, 20_____ ____________________________________

IN PRESENCE OF _________________________________________________________________

NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS
WRITTEN UPON THE FACE OF THIS CERTIFICATE IN EVERY PARTICULAR, WITHOUT
ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.