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                                                                   EXHIBIT 10.15


                                AMENDMENT NO. 1
                                       TO
                                CREDIT AGREEMENT

     THIS AMENDMENT (the "Amendment"), dated as of July 10, 1998 by and among
ANALYTICAL SURVEYS, INC. (the "Borrower"), the BANKS listed on the signature
page hereof (each a "Bank") and BANK ONE, COLORADO, N.A., as Agent (the
"Agent").

                                  WITNESSETH

     WHEREAS, the Borrower, the Banks and the Agent are parties to a Credit
Agreement dated as of June 3, 1998 (the "Credit Agreement") (capitalized terms
used and not otherwise defined herein shall have the meanings ascribed thereto
in the Credit Agreement);

     WHEREAS, the Borrower has requested and the banks have agreed to the
amendments of certain terms and conditions of the Credit Agreement more fully
set forth herein; and

     WHEREAS, the amendments contained herein shall be of benefit, either
directly or indirectly, to the Borrower.

     NOW THEREFORE, in consideration of the covenants, conditions and agreements
set forth herein, the parties agree as follows:

     1.     AMENDMENTS.   Upon and after the effectiveness of this Amendment (as
defined in Section 3  below):

            (a)    Subparagraph (ii) of the defined term "Applicable Margin" in
SECTION 1.1 of the Credit Agreement is restated in its entirety to read as
follows:

     (ii)   Notwithstanding the foregoing, the Applicable Margin will be equal
     to the LIBOR Base Rate + 2.25% or the Prime Rate + 0.50%, as the case may
     be, from the Effective Date to July 6, 1998, at which time the Applicable
     Margin shall be the LIBOR Base Rate + 1.25% or the Prime Rate + 0.0%, as
     the case may be, and thereafter shall be subject to adjustment, if
     necessary, five (5) days after delivery of the Compliance Certificate
     accompanying the financial statements furnished for the period ended May
     31, 1998.  Such financial statements for the period ended May 31, 1998
     shall be delivered to the Agent on or before July 10, 1998.

            (b)    The defined term "Commitment Fee Rate" is amended by the
restatement in its entirety of the last sentence of the definition to read as
follows:

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            Notwithstanding the foregoing, the Commitment Fee Rate shall be
            0.250% from the Effective Date until July 6, 1998, at which time the
            Commitment Fee Rate shall be 0.150%, and thereafter shall be subject
            to adjustment, if necessary, five (5) days after delivery of the
            Compliance Certificate accompanying the financial statements
            furnished for the period ended May 31, 1998.  Such financial
            statements for the period ended May 31, 1998 shall be delivered to
            the Agent on or before July 10, 1998.

            (c)    SECTION 5.2(a)(ii) of the Credit Agreement is restated in its
entirety to read as follows:

            MINIMUM FIXED CHARGE COVERAGE RATIO.  Fail to maintain a ratio of
            Trailing Four Quarter EBITDA  to Fixed Charges of not less than 1.3
            to 1.0.

     2.     REPRESENTATIONS AND WARRANTIES.  In order to induce the Banks to
agree to amend the Credit Agreement, the Borrower makes the following
representations and warranties, which shall survive the execution and delivery
of this Amendment:

            (a)    Prior to and as of the date first referenced above, no Event
of Default has occurred and as of the date first referenced above no Event of
Default will exist immediately after giving effect to the amendments contained
herein; and

            (b)    Each of the representations and warranties set forth in
ARTICLE IV of the Credit Agreement are true and correct as though such
representations and warranties were made at and as of the date first referenced
above, except to the extent that any such representations or warranties are made
as of a specified date or with respect to a specified period of time, in which
case such representations and warranties shall be made as of such specified date
or with respect to such specified period.  Each of the representations and
warranties made under the Credit Agreement shall survive to the extent provided
therein and not be waived by the execution and delivery of this Amendment.

     3.     EFFECTIVENESS.  The amendments to the Credit Agreement contained in
Section 1 of this Amendment shall become effective as of the date first
referenced above after the Borrower shall have executed a copy of this Amendment
and shall have delivered the same to the Banks and the Agent.

     4.     PAYMENT OF EXPENSES.  The Borrower hereby agrees to pay all
reasonable costs and expenses incurred by the Agent in connection with the
preparation, execution and delivery of this Amendment and any other documents or
instruments which may be delivered in connection herewith, including, without
limitation, the reasonable fees and expenses of Davis, Graham & Stubbs LLP,
counsel for the Agent.

     5.     COUNTERPARTS. This Amendment may be executed in counterparts and by
different parties hereto in separate counterparts, each of which, when so
executed and delivered, shall be deemed to be an original and all of which, when
taken together, shall constitute one and the same instrument.

     6.     RATIFICATION.  The Credit Agreement is and shall continue to be in
full force and effect and is hereby in all respects confirmed, approved and
ratified.  All terms and conditions of the Credit Agreement remain the same.


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     7.     GOVERNING LAW.  The rights and duties of the Borrower, the Banks and
the Agent under this Amendment shall be governed by the law of the State of
Colorado.


     IN WITNESS WHEREOF,  the parties have caused this Amendment to be duly
executed as of the date first written above.

ANALYTICAL SURVEYS, INC.                BANK ONE, COLORADO, N.A.,
                                            as Agent and Bank


By  /s/ Scott C. Benger                 By  /s/ Shaun P. McCarthy
  -------------------------               -------------------------
     Scott C. Benger                          Shaun P. McCarthy
     Senior Vice President-Finance,            Vice President
     Secretary and Treasurer


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