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                                                                EXHIBIT 10(12.2)

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                                                                EXHIBIT 10(12.2)

                                SECOND AMENDMENT

         THIS SECOND AMENDMENT (this "Second Amendment") dated as of February
23, 1998 is to the Amended and Restated Credit Agreement (the "Credit
Agreement") dated as of July 25, 1997 among LAYNE CHRISTENSEN COMPANY (the
"Company"), LAYNE CHRISTENSEN AUSTRALIA PTY LIMITED ("Layne Australia"), various
financial institutions and BANK OF AMERICA NATIONAL TRUST AND SAVINGS
ASSOCIATION, as Agent (in such capacity, the "Agent"). Unless otherwise defined
herein, terms defined in the Credit Agreement are used herein as defined
therein.

         WHEREAS, the parties hereto have entered into the Credit Agreement
which provides for (i) the Banks to make U.S. Loans to the Company from time to
time, (ii) the Australian Banks to make Australian Loans to Layne Australia from
time to time, and (iii) the Issuer to issue Letters of Credit for the account of
the Company (or jointly for the account of the Company and any Subsidiary) from
time to time and for the Banks to purchase participations therein; and

         WHEREAS, the parties hereto desire to amend the Credit Agreement in
certain respects as more fully set forth below;

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration (the receipt and sufficiency of which are hereby
acknowledged), the parties hereto agree as follows:

         SECTION 1. AMENDMENTS. Effective on (and subject to the occurrence of)
the Second Amendment Effective Date, the Credit Agreement shall be amended as
set forth in SECTION 1.1 and 1.2 below.

         Section 1.1 SUBSECTION 10.11(H). Subsection 10.11(h) hall be amended by
deleting the amount "$5,000,000" therein and substituting "$10,000,000"
therefor.

         Section 1.2 SUBSECTION 10.11(J). Subsection 10.11(j) hall be amended by
deleting the amount "$10,000,000" therein and substituting "$15,000,000"
therefor.

         SECTION 2. EFFECTIVENESS. The amendments set forth in SECTION 1 above
shall become effective, as of the day and year first above written, on such date
(the "Second Amendment Effective Date") that the Agent shall have received
counterparts of this Second Amendment executed by the Company and the Required
Banks.

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         SECTION 3.  MISCELLANEOUS.

         SECTION 3.1 CONTINUING EFFECTIVENESS. ETC. As herein amended, the
Credit Agreement shall remain in full force and effect and is hereby ratified
and confirmed in all respects.

         SECTION 3.2 COUNTERPARTS. This Second Amendment may be executed in any
number of counterparts and by the different parties on separate counterparts,
and each such counterpart shall be deemed to be an original but all such
counterparts shall together constitute one and the same Second Amendment.

         SECTION 3.3 GOVERNING LAW. This Second Amendment shall be a contract
made under and governed by the internal laws of the State of Illinois.

         SECTION 3.4 SUCCESSORS AND ASSIGNS. This Second Amendment shall be
binding upon the Company, Layne Australia, the Banks and the Agent and their
respective successors and assigns, and shall inure to the benefit of the
Company, Layne Australia, the Banks and the Agent and the successors and assigns
of the Banks and the Agent.

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         Delivered at Chicago, Illinois, as of the day and year first above
written.


                             LAYNE CHRISTENSEN COMPANY


                             By: /s/ Jerry W. Fanska
                                ------------------------------------------
                             Title: Vice President-Finance
                                   ---------------------------------------



                              BANK OF AMERICA NATIONAL TRUST AND SAVINGS 
                                    ASSOCIATION,
                                    as Agent


                             By: /s/ R. G. Stapleton
                                ------------------------------------------
                                        Managing Director



                             BANK OF AMERICA NATIONAL TRUST AND SAVINGS 
                             ASSOCIATION, as a Bank


                             By: /s/ R. G. Stapleton
                                ------------------------------------------
                                       Managing Director



                             MERCANTILE BANK, as Co-Agent and
                             as a Bank


                             By: /s/ Brian Hoban
                                ------------------------------------------
                             Title:  Corporate Banking Officer
                                   ---------------------------------------

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                             MICHIGAN NATIONAL BANK, as Co-Agent and as a Bank


                             By: /s/ Christopher J. Mayone
                                ------------------------------------------
                             Title: Commercial Relationship Manager
                                   ---------------------------------------



                             THE BANK OF NOVA SCOTIA


                              By: /s/ F.C.H. Ashby
                                ------------------------------------------
                              Title:  Senior Manager Loan Operations
                                   ---------------------------------------



                             SOCIETE GENERALE - CHICAGO BRANCH


                             By: /s Robert W. Bolt
                                ------------------------------------------
                              Title: Vice President
                                   ---------------------------------------

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