GUARANTY


     THIS GUARANTY AGREEMENT, dated as of June 3, 1998, is entered into by 
ASI LANDMARK, INC., a Colorado corporation ("GUARANTOR"), and BANK ONE, 
COLORADO, N.A., a national banking association having an office at the Denver 
Banking Center, 30 Pikes Peak Avenue, Colorado Springs, Colorado 80903, in 
its capacity as Agent for the Banks (the "AGENT").  


                                   RECITALS

                                   ARTICLE 1

     The Guarantor is a wholly-owned subsidiary of ANALYTICAL SURVEYS, INC., 
a Colorado corporation (the "BORROWER").


                                   ARTICLE 2

     The Borrower, the Banks and the Agent have entered into a Credit 
Agreement dated June 3, 1998 (together with all schedules and exhibits 
thereto, as the same may be supplemented, modified, amended or restated from 
time to time in the manner provided therein, the "CREDIT AGREEMENT," which is 
incorporated herein by reference as if fully set forth), pursuant to which 
the Agent, for the ratable benefit of the Banks, has agreed to make available 
to the Borrower a revolving line of credit in the maximum principal amount 
outstanding at any one time of ELEVEN MILLION DOLLARS ($11,000,000), a term 
loan in the principal amount of SIXTEEN MILLION DOLLARS ($16,000,000) and an 
acquisition loan in the principal amount of TEN MILLION DOLLARS ($10,000,000).


                                   ARTICLE 3

     The Guarantor will benefit by the making of loans under the Credit 
Agreement.



                                   ARTICLE 4

     As a condition precedent to the extension of loans under the Credit
Agreement, the Agent requires, among other things, that the Guarantor
unconditionally and irrevocably guarantees the full and punctual repayment of
all loans advanced under the Credit Agreement and all other related Obligations
owing by the Borrower to the Agent, for the ratable benefit of the Banks.


                                  AGREEMENT

     NOW, THEREFORE, for and in consideration of the foregoing recitals, the 
extension of the loans under the Credit Agreement and other good and valuable 
consideration, the receipt and sufficiency of which is hereby acknowledged, 
the Guarantor and the Agent agree as follows:


                                  ARTICLE I

                      CERTAIN DEFINITIONS AND REFERENCES

     SECTION 1.1  Terms Defined in Credit Agreement.  Reference is hereby 
made to the Credit Agreement for statements of terms thereof.  All 
capitalized terms used in this Guaranty which are defined in the Credit 
Agreement but which are not otherwise defined herein shall have the meanings 
provided in the Credit Agreement.

     SECTION 1.2  GENERAL DEFINITIONS.  As used in this Guaranty, in addition 
to the terms defined in the preamble and the Recitals hereto, the following 
capitalized terms shall have the meanings respectively assigned to them below:

          "AGENT" shall mean Bank One, Colorado, N.A., a national banking 
association having its principal offices at 1125 Seventeenth Street, Third 
Floor, Denver, Colorado 80202.

          "BANKS" shall mean (a) the Agent and the Banks under that certain 
Credit Agreement dated as of June 3, 1998, by and among the Borrower, the 
Banks listed therein and the Agent; and (b) any Person that has been assigned 
any or all of the rights or obligations of a Bank pursuant to SECTION 8.14 of 
the Credit Agreement.

          "BORROWER" shall have the meaning assigned to it in the Recitals 
hereto.

          "CODE" shall mean the Uniform Commercial Code as enacted in the 
State of Colorado, C.R.S. Section  4-1-101 ET SEQ., and any successor 
statutes thereto.


                                       2


          "COLLATERAL" shall mean, collectively all property of whatever 
type, in which the Banks shall receive a security interest pursuant to the 
Credit Agreement or any other Loan Instrument.

          "CREDIT AGREEMENT" shall have the meaning assigned to it in the 
Recitals hereto.

          "DEFAULT" means any event or state of affairs that, with the giving 
of notice or the passage of time (or both) would constitute an Event of 
Default.

          "EVENT OF DEFAULT" shall mean the occurrence of any one or more of 
the events identified in SECTION 6.1 of the Credit Agreement.

          "GUARANTOR" shall have the meaning specified in the introductory 
paragraph hereof.

          "GUARANTY" shall mean this Guaranty Agreement, together with all 
schedules and exhibits hereto, as the same may be supplemented, modified, 
amended or restated from time to time in the manner provided herein.

          "LOAN OR LOANS" shall have the meaning assigned to the terms "Loan" 
and "Loans" in SECTION 1.1 of the Credit Agreement.

          "LOAN INSTRUMENTS" shall mean and include collectively: (a) the 
Credit Agreement; (b) the Notes; and (c) all other instruments, agreements 
and documents, whether now or hereafter existing or executed, executed and 
delivered by Borrower or any guarantor in connection with the Obligations, as 
any such instrument may be supplemented, modified, amended or restated from 
time to time in the manner provided therein.

          "MATERIAL ADVERSE EFFECT" means any material and adverse effect, 
whether individually or in the aggregate, upon (a) the assets, business, 
operations, properties or condition, financial or otherwise, of the Borrower 
and its Subsidiaries, taken as a whole, (b) the ability of the Borrower to 
make payment as and when due of all or any part of the Obligations, or (c) 
the Collateral.

          "NOTES" shall have the meaning assigned to the term "Notes" in 
SECTION 1.1 of the Credit Agreement.

          "OBLIGATIONS" shall have the meaning assigned to the term 
"Obligations" in SECTION 1.1 of the Credit Agreement.

          "PERSON" means any individual, corporation, company, voluntary 
association, partnership, joint venture, limited liability company, limited 
liability partnership, trust, unincorporated organization or government (or 
any agency, instrumentality or political subdivision thereof).


                                       3


     SECTION 1.3  TERMS DEFINED IN CODE.  All terms used in this Guaranty 
which are defined in the Code and not otherwise defined herein or in the 
Credit Agreement shall have the meanings provided in the Code. 

     SECTION 1.4  AMENDMENT OF DEFINED INSTRUMENTS.  Unless the context 
otherwise requires or unless otherwise provided herein, references in this 
Guaranty to a particular agreement, instrument or document also refer to and 
include all renewals, extensions, amendments, modifications, supplements or 
restatements of any such agreement, instrument or document.

     SECTION 1.5  REFERENCES, TITLES, ETC.  All references in this Guaranty 
to Articles, Sections, Subsections and other subdivisions refer to the 
Articles, Sections, Subsections and other subdivisions of this Guaranty 
unless expressly provided otherwise.  The words "this Guaranty", "herein", 
"hereof", "hereby", "hereunder" and words of similar import refer to this 
Guaranty as a whole and not to any particular subdivision unless expressly so 
limited.  Pronouns in masculine, feminine and neuter gender shall be 
construed to include any other gender.  Words in the singular form shall be 
construed to include the plural and words in the plural form shall be 
construed to include the singular, unless the context otherwise requires.


                                  ARTICLE II

                              GUARANTY OF PAYMENT

     SECTION 2.1  GUARANTY.  The Guarantor hereby irrevocably, absolutely and 
unconditionally: (a) guarantees the due and punctual payment and performance 
when due, whether at stated maturity, by acceleration or otherwise, of the 
Obligations; and (b) agrees to pay any and all expenses (including reasonable 
attorneys' fees and disbursements) which may be paid or incurred by the Agent 
in enforcing any rights with respect to, or collecting, any or all of the 
Obligations and/or enforcing any rights with respect to, or collecting 
against, the Guarantor under this Guaranty.

     SECTION 2.2  GUARANTY OF PAYMENT AND NOT OF COLLECTION.  This Guaranty 
is a guarantee of payment, and not of collection, and a debt of the Guarantor 
for its own account.  Accordingly, the Agent shall not be obligated or 
required before enforcing this Guaranty against Guarantor: (a) to pursue any 
right or remedy the Agent may have against the Borrower or any other 
guarantor of the Obligations in any court, tribunal or otherwise; (b) to make 
any claim in a liquidation or bankruptcy of the Borrower, or any other 
guarantor of the Obligations; (c) to make demand of the Borrower, or any 
other guarantor of the Obligations; or (d) to enforce or seek to enforce or 
realize upon any Collateral or other security held by the Agent or any other 
party which may secure any of the 


                                       4


Obligations.  In this connection, the Guarantor hereby waives any right it 
may have to require the Agent to take action against the Borrower or any 
other guarantor of the Obligations.

     SECTION 2.3  CONTINUING GUARANTY.  The Guarantor agrees that:  (a) this 
is an open and continuing guaranty of payment and satisfaction, whether the 
Obligations are now or hereafter existing, acquired or created, and 
irrespective of the fact that from time to time under the terms and 
provisions of the Loan Instruments, monies may be advanced, repaid and 
readvanced and the outstanding balance of the Loans may be zero; and (b) the 
Obligations shall not be deemed to have been otherwise fully paid and 
satisfied so long as the Notes, or any other evidence of indebtedness shall 
have any continuing force or effect.  This Guaranty of payment and 
satisfaction will not be discharged until payment in full of all of the 
Obligations, and the Banks' Commitments under the Credit Agreement have been 
terminated.  No payment or payments made by any other person in payment of 
the Obligations shall be deemed to modify, reduce, release or otherwise 
affect the liability or limitations of the Guarantor hereunder until the 
Obligations are indefeasibly paid in full and the Banks' Commitments under 
the Credit Agreement have been terminated.

     SECTION 2.4  GUARANTY ABSOLUTE, SURVIVAL OF REPRESENTATIONS, ETC.  The 
Guarantor covenants and agrees that all of the representations, warranties, 
covenants and other agreements and obligations of Guarantor under this 
Guaranty and the other Loan Instruments: 

          (a)  shall be absolute and unconditional irrespective of the 
validity, legality, binding effect or enforceability of any of the terms and 
provisions of any of the Loan Instruments; 

          (b)  shall survive the execution and delivery of this Guaranty and 
the other Loan Instruments and the advance, repayment and readvance of any or 
all of the monies to be lent thereunder;

          (c)  shall remain and continue in full force and effect without 
regard to any waiver, modification, extension, renewal, consolidation, 
spreading, amendment or restatement of any other term or provision of any 
Loan Instrument (including without limitation any increase in the 
Obligations), to any full, partial or non-exercise of any of the Agent's 
rights, powers, privileges, remedies and interests under any Loan Instrument, 
against any person or with respect to any Collateral, to any release or 
subordination of all or any part of any Collateral, to any statute of 
limitations or similar time constraint under any applicable law, to any 
investigation, analysis or evaluation by the Agent or its designees of the 
assets, business, operations, properties or condition (financial or 
otherwise) of the Guarantor, the Borrower or any other person, to any act or 
omission on the part of the Agent or any other person, or to any other event 
that otherwise might constitute a legal or equitable counterclaim, defense or 
discharge of a surety or guarantor; 


                                       5


          (d)  shall not be subject to any defense, counterclaim, set-off, 
right of recoupment, abatement, reduction or other claim or determination 
that the Guarantor or the Borrower may have against the Agent, the Banks, or 
any other person;
 
          (e)  shall not be diminished or qualified by the death, disability, 
dissolution, reorganization, insolvency, bankruptcy, custodianship or 
receivership of the Guarantor, the Borrower or any other guarantor, surety or 
pledgor or any other person, or the inability of any of them to pay their 
debts or perform or otherwise satisfy their obligations as they become due 
for any reason whatsoever; and

          (f)  shall remain and continue in full force and effect regardless 
of any other circumstance which might otherwise constitute a defense 
available to, or a discharge of, the Guarantor; it being agreed that the 
obligations of the Guarantor under this Guaranty shall not be satisfied or 
discharged except as expressly provided in this Guaranty.


                                 ARTICLE III

                             CONSENTS AND WAIVERS

     SECTION 3.1  CONSENT.  Without limiting the generality of the foregoing 
Sections or any other term or provision of this Guaranty, the Guarantor  
agrees and consents that, without notice to the Guarantor, at any time, and 
from time to time:

          (a)  the amount of the Loans, the rates of interest thereon or any 
other Obligations may be increased or otherwise changed;

          (b)  the time, manner, place and other terms and provisions of 
payment or performance of the Obligations may be extended, modified, amended, 
restated or otherwise changed;

          (c)  any partial or late payment or any payment during the 
continuance of any default under the Loan Instruments may be accepted in 
whole or in part or rejected;

          (d)  any Collateral securing or intended to secure any obligations 
under any Loan Instrument may be sold, conveyed, assigned or otherwise 
realized upon, dealt with or disposed of in whole or in part;

          (e)  any mortgage or other security interest in any such Collateral 
may be held without due recordation or other perfection (whether 
intentionally or otherwise), may be recorded or otherwise perfected, or may 
be assigned, released, subordinated or otherwise impaired, dealt with or 
disposed of in whole or in part;


                                       6


          (f)  any one or more payments, distributions and proceeds received 
from or in respect of the Guarantor, the Borrower, any other guarantor, 
surety or pledgor or any other person or any such Collateral may be applied 
to any of the Obligations, or if not designated therefore, or otherwise 
restricted thereto, may be applied to other indebtedness of the Guarantor, 
the Borrower, or any such other guarantor, surety, pledgor or other person 
owed to the Agent or any of its affiliates;

          (g)  the liability of the Guarantor, the Borrower, any other 
guarantor, surety or pledgor or any other person to pay any and all of the 
Obligations may be settled, or compromised or released, in whole or in part;

          (h)  the rights of set-off of the Agent may be exercised as 
provided under this Guaranty, any other Loan Instrument or applicable law 
against any of the deposits, assets, properties and indebtedness subject 
thereto, without any demand on or notice to the Guarantor or the Borrower, 
without regard to the frequency of exercise thereof, and whether or not the 
relevant Obligations shall then be matured;

          (i)  any representation, warranty, covenant or other term or 
provision of any Loan Instrument, or any part thereof, may be a subject of 
one or more waivers of applicability or consents to nonperformance, 
noncompliance or nonobservance, whether or not constituting defaults, or may 
be otherwise not exercised or enforced (whether intentionally or otherwise);

          (j)  any one or more of this Guaranty, the Notes and any other Loan 
Instrument, or any one or more of the rights, powers, privileges, remedies 
and interests of the Agent herein or therein, may be sold, conveyed, assigned 
or otherwise transferred in whole or part (including participations or other 
undivided interests) to any other person; and/or

          (k)  any other right, power, privilege, remedy or interest of the 
Agent under the Guaranty, the Notes, any other Loan Instrument or applicable 
law may be exercised or enforced by the Agent or its designee, which exercise 
or enforcement may be delayed, discontinued or otherwise not pursued or 
exhausted for any or no reason whatsoever, or any such right, power, 
privilege, remedy or interest may be waived, omitted or otherwise not 
exercised or enforced (whether intentionally or otherwise), in the sole and 
absolute discretion of the Agent.

     SECTION 3.2  WAIVER.  The Guarantor, to the fullest extent permitted by 
law, hereby irrevocably waives each of the following:

          (a)  any duty on the part of the Agent to disclose to the Guarantor 
any matter, fact or thing relating to the business, operation or condition of 
the Borrower, or its assets now known or hereafter known by the Agent;


                                       7


          (b)  any and all notice of:  (i) acceptance of this Guaranty; (ii) 
any action taken or omitted in reliance hereon; and (iii) any default in the 
payment of any sums due pursuant to the Obligations, or any Loan Instrument 
or otherwise;

          (c)  presentment, demand for payment, protest or notice of protest 
relating to this Guaranty, the Obligations and/or any of the Loan Instruments;

          (d)  any and all notice of the occurrence or continuance of any 
Default, Event of Default or any event that (with the giving of notice or the 
passage of time or both) could constitute a Default, under any of the Loan 
Instruments, or of any other material or adverse event or Material Adverse 
Effect;

          (e)  any and all notice of the terms, time, and place of any public 
or private sale of any of the Collateral whether required by the Code or 
otherwise;

          (f)  any "one action" or anti-deficiency law or any other law which 
may prevent the Agent from bringing any action, including a claim for 
deficiency, against the Guarantor, before or after the Agent's commencement 
or completion of any foreclosure action, either judicially or by exercise of 
a power of sale;

          (g)  any election of remedies by the Agent which destroys or 
otherwise adversely affects the Guarantor's subrogation rights or the 
Guarantor's rights to proceed against the Borrower for reimbursement, 
including without limitation, any loss of right the Guarantor may suffer by 
reason of any law limiting, qualifying, or discharging the Obligations;

          (h)  any disability or other defense of the Borrower or any other 
guarantor, or of any other person, or by reason of the cessation of the 
liability of the Borrower from any cause whatsoever, other than payment in 
full in legal tender, of the Obligations;

          (i)  any right to claim discharge of the Obligations on the basis 
of unjustified impairment of any Collateral;

          (j)  any statute of limitations, if at any time any action or suit 
brought by the Agent against the Guarantor is commenced there is outstanding 
any of the Obligations which are not barred by any applicable statute of 
limitations;

          (k)  any defenses given to guarantors at law or in equity other 
than actual payment and performance of the Obligations including all 
defenses based upon suretyship or impairment of collateral pursuant to C.R.S.
Section 4-3-603;


                                       8


          (l)  any and all right, if any, to require the Agent to:  (i) 
continue lending money or to extend other credit to the Borrower; (ii) 
proceed directly against, marshall or exhaust any of the Collateral; (iii) 
pursue any remedy within the Agent's power; or (iv) commit any act or 
omission of any kind, at any time, with respect to any matter whatsoever; and

          (m)  any other proof, notice or demand of any kind whatsoever with 
respect to any or all of the Obligations or promptness in making any claim or 
demand under this Guaranty or any of the Loan Instruments.  No act or 
omission of any kind in connection with any of the foregoing shall in any way 
impair or otherwise affect the legality, validity, binding effect or 
enforceability of any term or provision of this Guaranty or any of the 
obligations of the Guarantor hereunder.

     SECTION 3.3  WAIVER OF SUBROGATION.  The Guarantor hereby irrevocably 
waives any and all claims and other rights that it now has or may hereafter 
acquire against the Borrower, or any other guarantor, that arise from the 
existence, payment, performance or enforcement of this Guaranty or any other 
Loan Instruments, including any right of subrogation, reimbursement, 
exoneration, contribution or indemnification and any right to participate in 
any claim or remedy of the Agent against the Borrower, any other guarantor or 
any Collateral that the Guarantor now has or hereafter acquires, whether or 
not such claim, remedy or right arises in equity or under contract, statute 
or common law, including the right to take or receive from the Borrower, 
directly or indirectly, in cash or other property, by set-off or in any other 
manner, payment or security on account of any such claim or other right.  If 
any amount is paid to the Guarantor in violation of the preceding sentence 
and the Obligations have not been paid in full, such amounts shall be deemed 
to have been paid to the Guarantor for the benefit of, and held in trust for 
the benefit of, the Agent and shall be forthwith paid to the Agent to be 
credited and applied to the Obligations, whether matured or unmatured, in 
accordance with the terms of the Loan Instruments.  This waiver of 
subrogation is for the benefit of the Agent and the foregoing waiver may not 
be revoked by the Guarantor without the prior written consent of the Agent.

     SECTION 3.4  ACKNOWLEDGMENT OF BENEFIT.  The Guarantor acknowledges that 
it has received and will receive direct and indirect benefits from the 
financing arrangements contemplated by the Loan Instruments and that the 
consents and waivers set forth in this Article are knowingly made in 
contemplation of such benefits.  

     SECTION 3.5  MISCELLANEOUS.  The Guarantor understands and agrees that 
the foregoing waivers and the other waivers, consents, releases and 
agreements contained in this Guaranty will, among other things, adversely and 
materially effect, and under certain circumstances may eliminate entirely, 
the Guarantor's rights or ability to collect monies from the Borrower that 
the Guarantor may have paid to the Borrower and defenses that the Guarantor 
might have to payment of the Obligations.  This result may occur because of 
the actions of the Agent or the Borrower, such as electing certain remedies 
and foregoing or delaying others, releasing security, or modifying the 
Obligations, all without notice to or consent from the Guarantor.  The 
Guarantor agrees that the foregoing waivers 


                                       9


and the other waivers, consents, releases and agreements contained in this 
Guaranty are made with the Guarantor's full knowledge of their significance 
and consequences and that, under the circumstances, the waivers are 
reasonable and not contrary to public policy or law.  If any such waiver is 
determined to be contrary to any applicable law or public policy, such waiver 
shall be effective only to the extent permitted by law or public policy.


                                   ARTICLE IV

                          SUBORDINATION OF INDEBTEDNESS

     SECTION 4.1  SUBORDINATION OF INDEBTEDNESS.  The Guarantor covenants and 
agrees that until all of the Obligations have been fully paid and satisfied, 
all indebtedness of the Borrower together with interest thereon, owed 
directly or indirectly to the Guarantor, whether now or hereafter existing, 
acquired or created, whether as a result of any payment made by the Guarantor 
or otherwise, shall be subordinate, junior and inferior in dignity and 
deferred as to payment to the full payment and satisfaction of all of the 
Obligations.  The Guarantor shall not seek any payment or exercise or enforce 
any right, power, privilege, remedy or interest that it may have with respect 
to any such indebtedness except with the prior written consent of the Agent 
and except in connection with a bankruptcy of the Borrower, in which case the 
Guarantor may file any claims it may have against the Borrower, subject to 
the provisions of Section 4.3 below to pay over any amounts received to the 
Agent.  Any payment, asset or property delivered to or for the benefit of the 
Guarantor in respect of any such indebtedness shall be accepted in trust for 
the benefit of the Agent and shall be promptly paid or delivered to the Agent 
to be credited and applied to the payment and satisfaction of the 
Obligations, whether matured or unmatured, or to be held by the Agent as 
additional Collateral.  The Guarantor agrees to execute such additional 
documents as the Agent may reasonably request to evidence the subordination 
provided in this Section.

     SECTION 4.2  SECURITY INTEREST IN INDEBTEDNESS.  The Guarantor hereby 
assigns and grants to the Agent a continuing security interest in and to all 
indebtedness owing from the Borrower to the Guarantor, whether or not 
hereafter existing, acquired or created, together with the proceeds thereof, 
all payments and other distributions with respect thereto and any and all 
renewals, substitutions, modifications and extensions of any and all of the 
foregoing, as security for the timely and full payment and satisfaction of 
the Obligations as and when due.  The Guarantor shall endorse and deliver to 
the Agent such instruments representing that indebtedness and shall execute 
and deliver to the Agent such financing statements and other documents as the 
Agent may deem necessary or desirable to evidence, confirm or perfect the 
foregoing security interest (which financing statements may be signed by the 
Agent on behalf and in the name of  the Guarantor if the Guarantor does not 
promptly sign and return the same).  In addition to the rights, powers, 
privileges, remedies and interest afforded to the Agent by this Guaranty and 
applicable law, if an Event of Default has occurred, the Agent may exercise 
any voting, consent, enforcement or other right, power, privilege, 


                                      10


remedy or interest pertaining to any item of such collateral to the same 
extent as if the Agent were the outright owner thereof. The Agent is hereby 
authorized, in the name of the Guarantor, from time to time to execute and 
file financing statements and continuation statements and to execute such 
other documents and to take such other actions as the Agent deems necessary 
or appropriate to perfect, preserve and enforce its rights under this 
Guaranty.

     SECTION 4.3  BANKRUPTCY.  In the event of insolvency, reorganization, or 
liquidation of the assets of the Borrower through bankruptcy, by an 
assignment for the benefit of creditors, by voluntary liquidation, or 
otherwise, the assets of the Borrower applicable to the payment of the claims 
of both the Agent and the Guarantor shall be paid to the Agent and shall, 
subject to Applicable Law, be applied by the Agent to the Obligations in such 
order and manner as the Agent may determine.  The Guarantor does hereby 
assign to the Agent all claims which it may have or acquire against the 
Borrower or against any assignee or trustee in bankruptcy of the Borrower; 
provided, however, that such assignment shall be effective only for the 
purpose of assuring to the Agent full payment in legal tender of all 
Obligations.


                                  ARTICLE V

                               RIGHT OF SET-OFF

     SECTION 5.1  RIGHT OF SET-OFF, ETC.  Upon the occurrence and during the 
continuance of any Event of Default, the Agent hereby is authorized at any 
time and from time to time, without notice to the Guarantor (any such notice 
being hereby expressly waived by the Guarantor), to set-off and apply, 
directly or through any of its affiliates, custodians, participants and 
designees, any and all deposits (whether general or special, time or demand, 
provisional or final, or individual or joint) and other assets and properties 
at any time held in the possession, custody or control of the Agent and any 
of its affiliates, custodians, participants and designees, and any 
indebtedness or other amount at any time held in the possession, custody or 
control of the Agent and any of its affiliates, custodians, participants and 
designees, and any indebtedness or other amount at any time owing by the 
Agent or any of its affiliates or participants, to or for the credit, account 
or benefit of the Guarantor against any and all of the Obligations now or 
hereafter existing under this Guaranty, whether or not the Agent shall have 
declared a Default, accelerated the Obligations or made any demand or taken 
any other action under this Guaranty, and although such Obligations may be 
unmatured.  The Guarantor hereby grants to the Agent a security interest in 
and to, among other things, all such deposits, assets, properties and 
indebtedness in the possession of the Agent's affiliates, custodians, 
participants and designees, and the Guarantor hereby authorizes any such 
person to so set-off and apply such amounts at such times and in such manner 
as the Agent may direct pursuant to this Section.  The Agent shall notify the 
Guarantor subject to such set-off after any such set-off and application; 
provided, however, that the failure to give such notice shall not affect the 
validity of such set-off and application.  In debiting any such account, the 
Obligations shall be 


                                      11


deemed to have been paid or repaid only to the extent of the funds actually 
available in the account notwithstanding any internal procedure of the Agent 
or any of its affiliates, custodians, participants and designees to the 
contrary.  The rights of the Agent under this Section are in addition to and 
without limitation of any other rights, powers, privileges, remedies and 
other interests (including, without limitation, other rights of set-off and 
security interests) that the Agent may have under this Guaranty and 
applicable law.


                                  ARTICLE VI

                           REPRESENTATIONS, WARRANTIES,
                             AGREEMENTS AND COVENANTS

     SECTION 6.1  GENERAL REPRESENTATIONS, WARRANTIES AND AGREEMENTS.  So 
long as any of the Obligations remain outstanding, the Guarantor hereby 
represents and warrants to, and agrees with, the Agent that:

          (a)  LEGAL CAPACITY.  The Guarantor has the legal capacity and 
power to execute and deliver this Guaranty.

          (b)  VALID AND BINDING.  This Guaranty, when executed and delivered 
by the Guarantor, will be a legal, valid and binding obligation of the 
Guarantor enforceable in accordance with the terms and provisions of this 
Guaranty, except as enforceability may be limited by applicable bankruptcy, 
insolvency or Applicable Laws affecting the enforcement and creditors' rights 
generally or by equitable principles relating to enforceability.

          (c)  NO VIOLATION OF LAW OR CONTRACT.  The execution and delivery 
of this Guaranty and the performance by the Guarantor of the obligations 
hereunder: (i) will not violate or be in conflict with (A) any provision of 
applicable law, or (B) any judgment, order, writ, injunction, decree or 
consent of any court or other judicial authority, and (ii) will not violate, 
be in conflict with, result in a breach of or constitute a default under, any 
material instrument, indenture, agreement or obligation of the Guarantor.

          (d)  NO OTHER CONDITIONS PRECEDENT.  There are no conditions 
precedent to the effectiveness of this Guaranty that have not been satisfied 
or waived.

          (e)  INDEPENDENT INVESTIGATION.  The Guarantor has, independently 
and without reliance upon the Agent and based on documents and information as 
it has deemed appropriate, made its own credit analysis and decision to enter 
into this Guaranty.


                                      12


          (f)  FINANCIAL STATEMENTS. The audited consolidated balance sheets 
of the Borrower and the Guarantors (for purposes of this Section 6.1(f), as 
"Guarantors" is defined in the Credit Agreement) at March 31, 1998, and the 
related consolidated statements of income and retained earnings of the 
Borrower and the Guarantors for the fiscal year then ended, and the related 
consolidated statements of income and retained earnings of the Borrower and 
Guarantors for the fiscal year ended March 31, 1998, copies of which have 
been furnished to the Banks, fairly present the financial condition of the 
Borrower and the Guarantors as at such date and the results of the operations 
of the Borrower and the Guarantors for the period ended on such date, all in 
accordance with Regulation S-X promulgated under the Securities Exchange Act 
of 1934, and since March 31, 1998, there has been no material adverse change 
in such condition or operations except as disclosed in SCHEDULE 4.1(f) of the 
Credit Agreement.

          (g)  LITIGATION.  Except as set forth in SCHEDULE 4.1(g) of the 
Credit Agreement, the Guarantor represents and warrants that there is no 
pending, or to the Guarantor's knowledge, threatened action or proceeding 
affecting the Guarantor or its properties or business activities, before any 
court, governmental agency or arbitrator, in which there is a reasonable 
possibility of a Material Adverse Effect or which purports to affect the 
legality, validity or enforceability of this Agreement or any Loan Instrument 
to which the Guarantor will be a party.

          (h)  SOLVENCY.   As of the date hereof, after giving effect to the 
direct and indirect indebtedness and other liabilities of the Guarantor 
arising under this Guaranty, the Guarantor:  (i) is solvent (I.E., the 
aggregate fair value of its assets exceeds the sum of its liabilities); (ii) 
has adequate capital; and (iii) is able to pay its debts as they mature.  Any 
term or provision of this Guaranty to the contrary notwithstanding, the 
aggregate amount of the Obligations guaranteed hereunder shall be reduced to 
the minimum extent necessary to prevent this Guaranty from violating or 
becoming voidable under applicable law relating to fraudulent conveyance or 
fraudulent transfer or similar laws affecting the rights of creditors 
generally.

          (i)  REVIEW OF CREDIT AGREEMENTS.  The Guarantor has reviewed and 
understands the Credit Agreement.

          (j)  NO MATERIAL MISREPRESENTATIONS OF OMISSIONS.  No 
representation, warranty, agreement or covenant of the Guarantor made or 
contained in this Guaranty and no report, statement, certificate, schedule or 
other document or information furnished by the Guarantor in connection with 
the transactions contemplated by this Guaranty contains or will contain a 
misstatement of a material fact or omits or will omit to state a material 
fact required to be stated therein in order to make it, in the light of the 
circumstances under which made, not misleading in any material respect as of 
the date made or deemed made.


                                      13


     SECTION 6.2  AFFIRMATIVE COVENANTS.  So long as any of the Obligations 
remain outstanding, the Guarantor hereby covenants and agrees that, unless 
the Agent shall consent otherwise in writing:

          (a)  NOTICE OF CERTAIN CHANGES.  Upon receipt of knowledge thereof, 
the Guarantor shall give, or cause to be given, immediate written notice to 
the Agent of (i) any change in the name or the location of the principal 
place of business of the Guarantor; (ii) any change in location or material 
change in the status of the Collateral, (iii) any act or event that violates, 
is in conflict with, results in a breach of or constitutes a Default (with or 
without the giving of notice or the passage of time or both) under (A) this 
Guaranty or the Loan Instruments, or (B) any other material instrument, 
indenture, agreement or obligation to which the Guarantor or the Borrower is 
a party or by which any part of the Collateral may be bound or subject; (iv) 
the occurrence of a Material Adverse Effect;  (v) any information required 
under SECTION 5.1(b) of the Credit Agreement applicable to the Guarantor.

          (b)  INSPECTION OF RECORDS.  The Guarantor shall, upon two weeks' 
notice (unless an Event of Default has occurred), allow the Agent or any 
representatives permitted by the terms of SECTION 5.1(h) of the Credit 
Agreement access to and right of inspection of the financial records of the 
Guarantor, all to the extent and in the same manner as provided in 
SECTION 5.1(h) of the Credit Agreement.

          (c)  PAYMENT OF TAXES AND CHARGES.  The Guarantor shall pay 
promptly when due all federal and material state and local taxes, 
assessments, liens and governmental charges and levies, in each case before 
the same become delinquent and before penalties accrue thereon, unless and to 
the extent that the same are being contested in good faith by appropriate 
proceedings.

          (d)  MAINTENANCE OF INSURANCE.  The Guarantor shall procure and 
maintain the third-party insurance identified in SCHEDULE 4.1(g) to the 
Credit Agreement, but in no event shall such insurance be for an amount less 
than the replacement cost of the assets so incurred, and issued by a 
financially sound and reputable independent insurance company or companies 
reasonably acceptable to the Agent.

          (e)  PERFORMANCE OF GUARANTY.  The Guarantor shall do and perform 
every act and discharge all of the obligations provided to be performed and 
discharged by the Guarantor under this Guaranty, at the times and in the 
manner specified herein.

          (f)  FURTHER ASSURANCES.  The Guarantor shall promptly cure any 
defects in the creation and issuance of this Guaranty.  The Guarantor at its 
expense will promptly execute and deliver to the Agent upon request all such 
other and further documents, agreements and instruments in compliance with or 
accomplishment of the covenants and agreements of the Guarantor in this 
Guaranty, or to correct any omissions in this Guaranty, or more fully to 
state the security obligations set out herein, or to perfect, protect or 
preserve any liens created pursuant to this Guaranty, or to 

                                      14


make any recordings, to file any notices, or obtain any consents, all as may 
be necessary or appropriate in connection herewith.

     SECTION 6.3  NEGATIVE COVENANTS.  So long as any Obligations remain 
outstanding, the Guarantor hereby covenants and agrees that, unless the Agent 
shall consent otherwise in writing:

          (a)  NO NEW DEBT.  The Guarantor shall not directly or indirectly 
permit, create, incur, assume, permit to exist, increase, renew or extend on 
or after the date hereof any material additional indebtedness on its part, 
except as otherwise permitted by Section 5.2(d) of the Credit Agreement;

          (b)  NO NEW LIABILITY.  The Guarantor shall not directly or 
indirectly guaranty, assume or otherwise become liable or responsible for the 
indebtedness or other obligations of any other persons, except any guarantee 
of indebtedness owed to the Agent, and except as otherwise permitted by 
SECTION 5.2(e) of the Credit Agreement; and

          (c)  NO DISPOSAL OF ALL ASSETS.  The Guarantor shall not sell, 
lease, assign, encumber, hypothecate, transfer, or otherwise dispose of all 
or substantially all of the Guarantor's assets, or any interest therein, 
except as permitted by SECTIONS 5.2(c) AND (g) of the Credit Agreement.


                                 ARTICLE VII

                                   REMEDIES

     SECTION 7.1  DEFAULT.  Upon the occurrence and during the continuation 
of any Event of Default or an event that would require or permit acceleration 
pursuant to the Credit Agreement of any outstanding indebtedness, then all of 
the Obligations shall be immediately due and payable by the Guarantor to the 
Agent.

     SECTION 7.2  REMEDIES.  In addition to all other rights, powers and 
remedies conferred herein, and through applicable law, upon the occurrence 
and during the continuation of an Event of Default, the Agent may reduce its 
claim to judgment or otherwise enforce, in whole or in part, this Guaranty.

     SECTION 7.3  OTHER RECOURSE.  The Guarantor waives any right it may have 
to require the Agent to proceed against any other person, exhaust any 
Collateral or other security for the Obligations, or pursue any other remedy 
in the Agent's power.


                                      15


     SECTION 7.4  REINSTATEMENT.  In the event any payment to the Agent of 
any of the Obligations, or any part thereof, at any time is rescinded or must 
otherwise be restored or returned by the Agent upon the insolvency, 
bankruptcy or reorganization of the Borrower, any guarantor or any other 
person, whether by order of any court, by any settlement approved by any 
court, or otherwise, then the terms and provisions of this Guaranty shall 
continue to apply, or shall be reinstated if not then in effect, as the case 
may be, with respect to the Obligations so rescinded, restored or returned, 
all as though such payment had never been made.

     SECTION 7.5  REMEDIES NOT EXCLUSIVE.  All rights, powers and remedies 
herein conferred are cumulative, and not exclusive, of:  (i) any and all 
other rights and remedies herein conferred or provided for; and (ii) any and 
all rights, powers and remedies conferred, provided for or existing at law or 
in equity, and the Agent shall, in addition to the rights, powers and 
remedies herein conferred or provided for, be entitled to avail itself of all 
such other rights, powers and remedies as may now or hereafter exist at law 
or in equity for the collection of and enforcement of the Obligations and the 
enforcement of the representations, warranties, agreements, covenants and 
indemnities contained in this Guaranty.

                                     ARTICLE VIII

                               MISCELLANEOUS PROVISIONS

     SECTION 8.1  PAYMENTS.  All payments of principal, interest, fees or 
other amounts due the Agent pursuant to this Guaranty shall be made in 
immediately available funds by 12:00 noon (Denver, Colorado time) on the date 
payment is due in U.S. Dollars to the Agent at the address contained in this 
Article for notices to the Agent.

     SECTION 8.2  JOINT AND SEVERAL OBLIGATIONS.  Although this Guaranty is 
made solely by the Guarantor, other persons or entities are also guaranteeing 
all or a portion of the Obligations.  The obligations of the Guarantor 
hereunder and such other guarantors, sureties or pledgors as may exist from 
time to time are joint and several.  Accordingly, the Guarantor is liable for 
the full amount of the Obligations notwithstanding the existence of other 
guarantors, sureties or pledgors.

     SECTION 8.3  ATTORNEYS' FEES; EXPENSES.  The Guarantor agrees to pay 
upon demand all of the Agent's costs and expenses, including reasonable 
attorneys' fees and the Agent's reasonable legal expenses, incurred in 
connection with the enforcement of this Guaranty.  The Agent may pay someone 
else to help enforce this Guaranty, and the Guarantor shall pay the costs and 
expenses of such enforcement.  The costs and expenses include the Agent's 
reasonable attorneys' fees and legal expenses whether or not there is a 
lawsuit, including reasonable attorneys' fees and legal expenses for 
bankruptcy proceedings (and including efforts to modify or vacate any 
automatic stay or injunction), appeals, any anticipated post-judgment 
collection services, reasonable experts' fees and 

                                      16



consultants' fees.  The Guarantor also shall pay all court costs and such 
additional fees as may be directed by the court.

     SECTION 8.4  MERGER OF THE BORROWER.  This Guaranty shall not be 
affected by any change in the name of the Borrower, or by the acquisition of 
the business of the Borrower by any person, firm or corporation, or by any 
change whatsoever in the capital structure or constitution of the Borrower, 
or by any merger, amalgamation or consolidation of the Borrower with any 
corporation, or by any dissolution or liquidation of the Borrower, but shall, 
notwithstanding the happening of any such event, continue to apply to all the 
Obligations.

     SECTION 8.5  INFORMATION.  The Guarantor assumes all responsibility for 
being and keeping informed of the financial condition and assets of the 
Borrower, and of all other circumstances bearing upon the risk of nonpayment 
of the Obligations and the nature, scope and extent of the risks that the 
Guarantor assumes and incurs hereunder, and agrees that the Agent will not 
have any duty to advise the Guarantor of information known to it or any Bank 
regarding such circumstances or risks.

     SECTION 8.6  FURTHER ASSURANCES.  The Guarantor agrees to do such 
further acts and things and to execute and deliver such statements, 
assignments, agreements, instruments and other documents as the Agent from 
time to time reasonably may request in connection with the administration 
maintenance, enforcement or adjudication of this Guaranty in order (a) to 
evidence, confirm, perfect or protect any lien or security interest granted 
or required to have been granted under this Guaranty, (b) to give the Agent 
or its designee confirmation and assurance of the Agent's rights, powers, 
privileges, remedies and interests under this Guaranty and applicable law, 
(c) to better enable the Agent to exercise any such right, power, privilege 
or remedy, or (d) to otherwise effectuate the purpose and the terms and 
provisions of this Guaranty, each in the form and substance as may be 
reasonably acceptable to the Agent. The Agent shall execute, acknowledge and 
deliver to the Guarantor such documents and take such other actions as the 
Guarantor reasonably may request in order to effectuate the purpose and terms 
and provisions of this Guaranty.

     SECTION 8.7  RELIANCE.  The Agent shall be entitled to reasonably rely 
upon any notice, consent, certificate, affidavit, statement, paper, document, 
writing or other communication reasonably believed by the Agent to be genuine 
and correct and to have been signed, sent or made by the proper person or 
persons, and upon opinions and advice of legal counsel (including counsel for 
the Guarantor), independent public accountants and other experts selected by 
the Agent.  The Agent shall be entitled to rely, and in entering into this 
Guaranty in fact has relied, upon the representations, warranties and other 
information respecting the Guarantor contained in this Guaranty 
notwithstanding any investigation, analysis or evaluation that may have been 
made or from time to time may be made by the Agent or its designees of all or 
any part of the assets, business, operations, properties or condition 
(financial or otherwise) of the Guarantor.

                                      17



     SECTION 8.8  EXCULPATION.  The Agent, the Banks and their designees, and 
their respective directors, officers, employees, attorneys and agents, shall 
not incur any liability (other than for a person's own acts or omissions 
breaching a duty owed to the Guarantor and amounting to gross negligence or 
willful misconduct as finally determined pursuant to applicable law by a 
governmental authority having jurisdiction) for acts and omissions arising 
out of or related directly or indirectly to this Guaranty or any of the Loan 
Instruments; and the Guarantor hereby expressly waives any and all claims and 
actions (other than those attributable to a person's own acts or omissions 
breaching a duty owed to a Guarantor and amounting to gross negligence or 
willful misconduct as finally determined pursuant to applicable law by a 
governmental authority having jurisdiction) against the Agent, the Banks and 
their designees, and their respective directors, officers, employees, 
attorneys and agents, arising out of or related directly or indirectly to any 
and all of the foregoing acts, omissions and circumstances.

     SECTION 8.9  INDEMNIFICATION.  The Agent, the Banks and their designees, 
and their respective directors, officers, employees, attorneys and agents, 
shall be indemnified, reimbursed, held harmless and, at the request of the 
Agent, defended by the Guarantor from and against any and all claims, 
liabilities, losses and expenses (including, without limitation, the 
reasonable disbursements, expenses and fees of their respective attorneys) 
that may be imposed upon, incurred by, or asserted against any of them, or 
any of their respective directors, officers, employees, attorneys and agents, 
arising out of or related directly or indirectly to this Guaranty or any of 
the Loan Instruments, except such as are occasioned by the indemnified 
person's own acts or omissions breaching a duty owed to a Guarantor or 
amounting to gross negligence or willful misconduct as finally determined 
pursuant to applicable law by a governmental authority having jurisdiction.

     SECTION 8.10  INTERPRETATION.  The parties acknowledge and agree that: 
each party and its counsel have reviewed and negotiated the terms and 
provisions of this Guaranty and have contributed to its revision; the normal 
rule of construction, to the effect that any ambiguities are resolved against 
the drafting party, shall not be employed in the interpretation of it; and 
its terms and provisions shall be construed fairly to all parties hereto and 
not in favor of or against any party, regardless of which party was generally 
responsible for the preparation of this Guaranty.

     SECTION 8.11  WAIVER AND MODIFICATION.  This Guaranty constitutes the 
entire agreement and understanding of the parties as to matters set forth in 
this Guaranty.  This Guaranty and the provisions hereof may be waived, 
amended, modified, changed, discharged or terminated only by an instrument in 
writing and signed by the Guarantor and the Agent.  No delay or omission on 
the part of the Agent in exercising any right under this Guaranty shall 
operate as a waiver of such right or any other right.  A waiver by the Agent 
of a provision of this Guaranty shall not prejudice or constitute a waiver of 
the Agent's right otherwise to demand strict compliance with that provision 
or any other provision of this Guaranty.  No prior waiver by the Agent, nor 
any course of dealing between the Agent and the Guarantor, shall constitute a 
waiver of any of the Agent's rights or any of the Guarantor's obligations as 
to any future transactions.  Whenever the consent of the Agent is 

                                      18



required under this Guaranty, the granting of such consent by the Agent in 
any instance shall not constitute continuing consent to subsequent instances 
where such consent is required and, unless otherwise provided herein, such 
consent may be granted or withheld in the sole and absolute discretion of the 
Agent.

     SECTION 8.12  BINDING AGREEMENT.  This Guaranty shall be binding upon 
the Guarantor and its successors and shall inure, together with the rights 
and remedies of the Agent, to the benefit of the Agent and its successors and 
assigns.

     SECTION 8.13  ASSIGNMENT.  The Guarantor may not assign its rights or 
delegate its duties hereunder without the Agent's prior written consent. 
However, the Agent may assign or otherwise transfer any rights under this 
Guaranty to the extent provided in Section 7.8 of the Credit Agreement, and 
such other person or entity shall thereupon become vested with all the 
benefits in respect thereof granted to the Agent herein or otherwise.

     SECTION 8.14  NOTICES.  Except as otherwise expressly provided in this 
Guaranty, any notice, request, demand or other communication permitted or 
required to be given under this Guaranty shall be in writing, shall be sent 
by one of the following means to the addressee at the address set forth below 
(or at such other address as shall be designated hereunder by notice to the 
other parties and persons receiving copies, effective upon actual receipt) 
and shall be deemed conclusively to have be given:  (i) on the first business 
day following the day timely deposited with Federal Express (or other 
equivalent national overnight courier) or United States Express Mail, with 
the cost of delivery prepaid; (ii) on the fifth business day following the 
day duly sent by certified or registered United States mail, postage prepaid 
and return receipt requested; or (iii) when otherwise actually delivered to 
the addressee.  If a written notice, certificate or signed item is expressly 
required by another provision of this Guaranty, a manually signed original 
must be delivered by the party giving it; any other notice, request, demand 
or other communication also may be sent by tested telex, telegram or 
telecopy, with the cost of transmission prepaid, and shall be deemed 
conclusively to have been given on the first business day following the day 
duly sent.  Copies may be sent by regular first-class mail, postage prepaid, 
to the persons, if any, set forth below, but any failure or delay in sending 
copies shall not affect the validity of any such notice, request, demand or 
other communication so given to a party.  The addresses of the parties and 
those persons receiving copies are as follows:

          If to the Agent, at the following address:

               Bank One, Colorado, N.A.
               30 Pikes Peak Avenue
               Colorado Springs, Colorado 80903
               Attn: Shaun P. McCarthy, Vice President
               Telecopy:  (719) 471-5213
          With a copy of all notices to:

                                      19



               Ted R. Sikora II, Esq.
               Davis, Graham & Stubbs LLP
               370 Seventeenth Street, 47th Floor
               Denver, Colorado  80202
               Telecopy:  (303) 893-1379

          If to the Guarantor, at the following address:

               ASI Landmark, Inc.
               c/o Analytical Surveys, Inc.
               1935 Jamboree Drive
               Colorado Springs, CO  80920
               Attn:     Scott C. Benger                    
               Telecopy:  (719) 528-5093

          With a copy of all notices to:

               Steven D. Miller, Esq.
               Sherman & Howard L.L.C.
               633 Seventeenth Street,    Suite 3000
               Denver, CO  80202
               Telecopy:  (303) 298-0940

     SECTION 8.15  PARTIAL INVALIDITY.  In the event that any provision hereof
shall be deemed to be invalid by any reason of the operation of any law or by
reason of the interpretation placed thereon by any court, this Guaranty shall be
construed as not containing such provision with respect to any jurisdiction
where such law or interpretation is operative, and the invalidity of such
provision shall not affect the validity of any remaining provision hereof, and
any and all other provisions hereof which are otherwise lawful and valid shall
remain in full force and effect.

     SECTION 8.16  GOVERNING LAW, JURISDICTION, VENUE AND WAIVER OF JURY TRIAL
RIGHTS.  THIS GUARANTY AND ALL MATTERS RELATING HERETO SHALL, EXCEPT TO THE
EXTENT OTHERWISE REQUIRED BY APPLICABLE LAW, BE GOVERNED BY AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH THE LAWS OF THE STATE OF COLORADO WITHOUT REGARD
TO CONFLICT OF LAWS PRINCIPLES.  THE GUARANTOR HEREBY SUBMITS TO THE
JURISDICTION AND VENUE OF THE STATE AND FEDERAL COURTS OF COLORADO AND AGREES
THAT THE AGENT MAY, AT ITS OPTION, ENFORCE ITS RIGHTS IN SUCH COURTS.  TO THE
EXTENT PERMITTED BY APPLICABLE LAW, THE GUARANTOR HEREBY IRREVOCABLY WAIVES THE
DEFENSE OF AN INCONVENIENT FORUM TO MAINTENANCE OF ANY ACTION OR PROCEEDING BY
THE BANK IN SUCH COURTS.  THE GUARANTOR HEREBY IRREVOCABLY WAIVES ALL RIGHT TO
TRIAL 

                                      20



BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM ARISING OUT OF OR
RELATING TO THIS GUARANTY OR ANY OF THE TRANSACTIONS CONTEMPLATED HEREBY.

     SECTION 8.17  COUNTERPARTS.  This Guaranty may be executed in any number of
counterparts and by different parties hereto on separate counterparts, each
constituting an original, but all together one and the same instrument.

     IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly
executed as of the date first above written.

                                        ASI LANDMARK, INC.


                                        By:
                                           ------------------------------
                                           Scott C. Benger 
                                           Vice President


                                        BANK ONE, COLORADO, N.A.,
                                        AS AGENT


                                        By:
                                           ------------------------------
                                           Shaun P. McCarthy
                                           Vice President

                                      21