Exhibit 10.4

        FIRST AMENDMENT TO 3-YEAR AND 364-DAY REVOLVING CREDIT AGREEMENTS


         This FIRST AMENDMENT TO 3-YEAR AND 364-DAY REVOLVING CREDIT AGREEMENTS
(this "Amendment") is dated as of June 13, 2002, and is entered into by and
among Black Hills Corporation, a South Dakota corporation (the "Borrower"), ABN
AMRO Bank N.V. in its capacity as administrative agent for the Banks party to
each of the Credit Agreements described below (in such capacity, the
"Administrative Agent"), and the Required Banks.

         WHEREAS, the Administrative Agent, the Banks and the Borrower have
entered into that certain 364-Day Credit Agreement (as the same has been
amended, extended, modified or restated, the "364-Day Credit Agreement") and
that certain 3-Year Credit Agreement (as the same has been amended, extended,
modified or restated, the "3-Year Credit Agreement") each dated as of August 28,
2001 and each among the Borrower, the financial institutions from time to time
party thereto (each a "Bank," and collectively the "Banks"), U.S. Bank, National
Association and The Bank of Nova Scotia, in their capacity as documentation
agents for the Banks thereunder (in such capacity, "Documentation Agents"),
Union Bank of California, N.A. and Bank of Montreal, in their capacity as
syndication agents for the Banks thereunder (in such capacity, "Syndication
Agents") and ABN AMRO Bank N.V. in its capacity as Administrative Agent for the
Banks thereunder (the 364-Day Credit Agreement and the 3-Year Credit Agreement
are each referred to individually as a "Credit Agreement" and collectively as
the "Credit Agreements");

         WHEREAS, the Borrower has requested that the Credit Agreement be
amended to, among other things, eliminate a downgrade of its S&P Rating or
Moody's Rating below investment grade as an Event of Default and the Banks are,
subject to the terms hereof, willing to so amend the Credit Agreement.

         NOW THEREFORE, in consideration of the mutual conditions and agreements
set forth in the Credit Agreements and this Amendment, and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto hereby agree as follows:

     1. Definitions.  Capitalized terms used in this Amendment, unless otherwise
defined herein, shall have the meaning ascribed to such terms in the Credit
Agreements.

     2.  Amendments.  Subject to the  conditions  set forth  below,  each Credit
Agreement is amended as follows:

          (a) Section 1.1 of each Credit Agreement is hereby amended by amending
     and restating the following definition in its entirety:


                                       1


                           "Material Adverse Effect" means a material adverse
                  effect on (i) the business, financial position or results of
                  operations of Borrower or Borrower and its Subsidiaries taken
                  as a whole, (ii) the ability of Borrower to perform its
                  material obligations under the Credit Documents, (iii) the
                  validity or enforceability of the material obligations of
                  Borrower under any Credit Document, (iv) the rights and
                  remedies of the Banks or the Administrative Agent against
                  Borrower; or (v) the timely payment of the principal of and
                  interest on the Loans or other amounts payable by Borrower
                  hereunder, provided, that a downgrade of Borrower's S&P Rating
                  and/or Moody's Rating shall not, in and of itself, be deemed a
                  "Material Adverse Effect" for purposes of this Agreement.

          (b) Section 1.1 of each Credit Agreement is hereby amended by amending
     and restating clause (v) of the definition of  "Indebtedness"  to be and to
     read as follows:

                            (v) all Guarantees issued by such Person, provided
                  that Long-Term Guaranties shall not be deemed "Indebtedness"
                  for purposes of calculating Borrower's compliance with the
                  financial covenants set forth in Sections 7.16, 7.17 and 7.18
                  hereof;

          (c)  Section  8.1 of each Credit  Agreement  is hereby  amended by (i)
     inserting the word "or" at the end of subsection (k) thereof, (ii) deleting
     the "; or" appearing at the end of subsection  (l) thereof and replacing it
     with ".", and (iii) deleting subsection (m) thereof in its entirety.

          (d) Schedule 1 to the 364-Day  Credit  Agreement is hereby  deleted in
     its entirety and a new Schedule 1 in the form of Schedule 1 (364-Day Credit
     Agreement) attached to this Amendment is hereby substituted therefor.

          (e) Schedule 1 to the 3-Year Credit Agreement is hereby deleted in its
     entirety  and a new  Schedule 1 in the form of  Schedule  1 (3-Year  Credit
     Agreement) attached to this Amendment is hereby substituted therefor.

          (f) Schedule 1 to Exhibit B of each Credit Agreement is hereby amended
     by changing the words "must not be less than"  appearing in Section G(7) of
     each such schedule to "not to exceed".

     3. Ratification.  The Borrower hereby ratifies,  acknowledges,  affirms and
reconfirms its rights,  interests and obligations under each Credit Document and
agrees to perform each of its  obligations  thereunder as and when required.  By
executing this Amendment,  the Borrower hereby further  ratifies,  acknowledges,
affirms and reconfirms that each Credit Document, as amended hereby, constitutes
a legal,  valid and binding obligation of the Borrower  enforceable  against the
Borrower in accordance with its terms,  and that each such Credit  Document,  as
amended hereby, is in full force and effect.


                                       2


     4.  Conditions.  The  effectiveness  of this  Amendment  is  subject to the
following conditions precedent (unless specifically waived in writing by the
Administrative Agent):

          (a) The  Borrower  and the  Required  Banks  shall have  executed  and
     delivered  this  Amendment,  and the Borrower  shall have  executed  and/or
     delivered such other documents and instruments as Administrative  Agent may
     require.

          (b) The  representations and warranties set forth in Section 5 of this
     Amendment shall be true and correct.

          (c)  All  proceedings   taken  in  connection  with  the  transactions
     contemplated  by this  Amendment and all documents,  instruments  and other
     legal  matters  incident  thereto  shall  be  reasonably   satisfactory  to
     Administrative Agent and its legal counsel.

     5.  Representations and Warranties.  To induce the Administrative Agent and
the Banks to enter into this Amendment,  the Borrower represents and warrants to
the  Administrative  Agent and the Banks that (i) the  execution,  delivery  and
performance  of  this  Amendment  has  been  duly  authorized  by all  requisite
corporate  action on the part of the Borrower and that this  Amendment  has been
duly  executed and  delivered by the Borrower and this  Amendment and the Credit
Agreements,  as amended hereby,  constitute valid and binding obligations of the
Borrower  enforceable in accordance with their respective terms, (ii) no Default
or Event of Default (after giving effect to this  Amendment) has occurred and is
continuing  under the Credit  Agreements  or would result from the execution and
delivery of this Amendment, and (iii) each of the representations and warranties
set forth in Section 5 of the Credit Agreements,  as amended hereby, is true and
correct in all material respects as of the date hereof,  except that if any such
representation or warranty relates solely to an earlier date it need only remain
true as of such date.

     6.  Severability.  Any  provision  of this  Amendment  held  by a court  of
competent  jurisdiction  to be  invalid  or  unenforceable  shall not  impair or
invalidate  the  remainder of this  Amendment  and the effect  thereof  shall be
confined to the provision so held to be invalid or unenforceable.

     7.  References.  Any  reference to the Credit  Agreements  contained in any
document,  instrument  or  agreement  executed  in  connection  with the  Credit
Agreements  shall be  deemed  to be a  reference  to the  Credit  Agreements  as
modified by this Amendment.

     8.   Counterparts.   This   Amendment  may  be  executed  in  one  or  more
counterparts, each of which shall constitute an original, but all of which taken
together  shall  be one and the  same  instrument.  This  Amendment  may also be
executed by facsimile and each  facsimile  signature  hereto shall be deemed for
all purposes to be an original signatory page.

                                       3


     9. Costs.  The Borrower  agrees to pay on demand all  reasonable  costs and
expenses  incurred by the  Administrative  Agent (including fees and expenses of
counsel)  incurred in connection  with the  negotiation  and preparation of this
Amendment.

     10.  Governing Law. The validity and  interpretation  of this Amendment and
the terms and conditions set forth herein, shall be governed by and construed in
accordance with the laws of the State of New York,  without giving effect to any
provisions  relating to conflict  of laws other than  section  5-1401 of the New
York General Obligations Laws.

     11. Miscellaneous. This Amendment shall be deemed to be a Credit Document.



           [- Remainder of Page Left Blank - Signature Pages Follow -]




                                       4



         In Witness Whereof, the parties hereto have caused this Agreement to be
duly executed and delivered in New York, New York by their duly authorized
officers as of the day and year first above written.


                         BLACK HILLS CORPORATION, a
                         South Dakota corporation

                         By:      _____________________________
                         Name:    _____________________________
                         Title:   _____________________________



                                       5




                         ABN AMRO BANK N.V., in its individual
                         capacity as a Bank and as Administrative
                         Agent

                         By:      _____________________________
                         Name:    David B. Bryant
                         Title:   Senior Vice President &
                                  Managing Director

                         By:      _____________________________
                         Name:    _____________________________
                         Title:   _____________________________



                                       6




                        UNION BANK OF CALIFORNIA, N.A.


                        By:      _____________________________
                        Name:    Robert J. Cole
                        Title:   Vice President



                                       7



                        U.S. BANK, NATIONAL
                        ASSOCIATION, in its individual capacity
                        as a Bank and as Documentation Agent

                        By:      _____________________________
                        Name:    Sandra Vollmer
                        Title:   Senior Lender



                                       8




                        BANK OF MONTREAL


                        By:      _____________________________
                        Name:    Ian M. Plester
                        Title:   Director



                                       9




                        THE BANK OF NOVA SCOTIA


                        By:      _____________________________
                        Name:    F.C.H. Ashby
                        Title:   Senior Manager Loan Operations



                                       10




                        CIBC INC., as a Lender


                        By:      _____________________________
                        Name:    M. Sanjeeva Senanayake
                        Title:   Executive Director
                                 CIBC World Markets Corp. As Agent


                                       11



                        COBANK, ACB



                        By:      _____________________________
                        Name:    Cathleen Reed
                        Title:   Assistant Vice President




                                       12




                        WELLS FARGO BANK, N.A.


                        By:      _____________________________
                        Name:    Thomas M. Foncannon
                        Title:   Senior Vice President




                                       13





                         MIZUHO CORPORATE BANK, LTD.


                         By:      _____________________________
                         Name:    Nobuyasu Fukatsu
                         Title:   Senior Vice President



                                       14




                          NATIONAL CITY BANK OF
                          MICHIGAN/ILLINOIS


                          By:      _____________________________
                          Name:    Mark R. Long
                          Title:   Senior Vice President



                                       15





                          NORDEUTSCHE LANDESBANK
                          GIROZENTRALE NEW YORK/
                          CAYMAN ISLANDS BRANCH


                          By:      _____________________________
                          Name:    Stephanie Finnen
                          Title:   Vice President

                          By:      _____________________________
                          Name:    Joseph Haas
                          Title:   Vice President



                                       16




                           CHANG HWA BANK, LOS ANGELES BRANCH


                           By:      _____________________________
                           Name:    James Lin
                           Title:   Senior Vice President and General Manager


                                       17





                      SCHEDULE 1 (364-Day Credit Agreement)


                                  PRICING GRID


- ------------------ ------------------- ------------ ------------------- -------------------
  If the Level       Subject to the        The        Subject to the      Subject to the
    Status Is        proviso below     Utilization    proviso below       proviso below
                     this grid, the     Fee Rate      this grid, the      this grid, the
                   Facility Fee Rate       is:      Eurodollar Margin    Base Rate Margin
                          is:                              is:                 is:
                                                            
- ------------------ ------------------- ------------ ------------------- -------------------
- ------------------ ------------------- ------------ ------------------- -------------------
Level I Status     0.080%              0.100%       0.420%                    0.000%
- ------------------ ------------------- ------------ ------------------- -------------------
- ------------------ ------------------- ------------ ------------------- -------------------
Level II Status    0.100%              0.125%       0.500%                    0.000%
- ------------------ ------------------- ------------ ------------------- -------------------
- ------------------ ------------------- ------------ ------------------- -------------------
Level III Status   0.125%              0.125%       0.625%                    0.000%
- ------------------ ------------------- ------------ ------------------- -------------------
Level IV Status    0.150%              0.125%       0.725%                    0.000%
- ------------------ ------------------- ------------ ------------------- -------------------
- ------------------ ------------------- ------------ ------------------- -------------------
Level V Status     0.200%              0.250%       0.800%                    0.000%
- ------------------ ------------------- ------------ ------------------- -------------------
- ------------------ ------------------- ------------ ------------------- -------------------
Level VI Status    0.600%              0.500%       1.400%                    0.475%
- ------------------ ------------------- ------------ ------------------- -------------------



         Each change in a rating shall be effective as of the date it is
announced by the applicable rating agency. Until the Borrower receives an S&P
Rating, the applicable Level shall be determined based upon the Borrower's
Moody's Rating.

         In the event that the Moody's Rating and the S&P Rating fall in
consecutive Levels, the rating falling in the lower Level (with Level I being
the highest Level and Level VI being the lowest Level) shall govern for purposes
of determining the applicable pricing pursuant to the above pricing grid. In the
event that the Moody's Rating and the S&P Rating fall in non-consecutive Levels,
the Level immediately above the Level in which the lower rating falls (with
Level I being the highest Level and Level VI being the lowest Level) shall
govern for purposes of determining the applicable pricing pursuant to the above
pricing grid.


                                       18




                      SCHEDULE 1 (3-Year Credit Agreement)

                                  PRICING GRID



- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
  If the Level       Subject to the        The        Subject to the     Subject to the      Subject to the
    Status Is        proviso below     Utilization    proviso below       proviso below    proviso below this
                     this grid, the     Fee Rate      this grid, the     this grid, the      grid, the Base
                   Facility Fee Rate       is:       L/C Fee Rate is:      Eurodollar        Rate Margin is:
                          is:                                              Margin is:
                                                                            
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
Level I Status     0.100%              0.100%       0.400%              0.400%                   0.000%
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
Level II Status    0.125%              0.125%       0.475%              0.475%                   0.000%
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
Level III Status   0.150%              0.125%       0.600%              0.600%                   0.000%
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
Level IV Status    0.175%              0.125%       0700%               0.700%                   0.000%
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
Level V Status     0.250%              0.250%       0.750%              0.750%                   0.000%
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------
Level VI Status    0.500%              0.500%       1.500%              1.500%                   0.500%
- ------------------ ------------------- ------------ ------------------- ------------------ --------------------



         Each change in a rating shall be effective as of the date it is
announced by the applicable rating agency. Until the Borrower receives an S&P
Rating, the applicable Level shall be determined based upon the Borrower's
Moody's Rating.

         In the event that the Moody's Rating and the S&P Rating fall in
consecutive Levels, the rating falling in the lower Level (with Level I being
the highest Level and Level VI being the lowest Level) shall govern for purposes
of determining the applicable pricing pursuant to the above pricing grid. In the
event that the Moody's Rating and the S&P Rating fall in non-consecutive Levels,
the Level immediately above the Level in which the lower rating falls (with
Level I being the highest Level and Level VI being the lowest Level) shall
govern for purposes of determining the applicable pricing pursuant to the above
pricing grid.