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                        THE 1998 STOCK OPTION PLAN
                                   OF
                          ECO SOIL SYSTEMS, INC.


      Eco Soil Systems, Inc., a Nebraska corporation (the "Company"), has 
adopted The 1998 Stock Option Plan of Eco Soil Systems, Inc. (the "Plan"), 
effective April 29, 1998, for the benefit of its eligible employees, 
consultants and directors.

      The purposes of this Plan are as follows:

      (1)   To provide an additional incentive for directors, key Employees 
and consultants to further the growth, development and financial success of the 
Company by personally benefiting through the ownership of Company stock which 
recognizes such growth, development and financial success.

      (2)   To enable the Company to obtain and retain the services of 
directors, key Employees and consultants considered essential to the long range 
success of the Company by offering them an opportunity to own stock in the 
Company which will reflect the growth, development and financial success of the 
Company.

                               ARTICLE I.

                              DEFINITIONS

      1.1.   GENERAL.  Wherever the following terms are used in this Plan they 
shall have the meanings specified below, unless the context clearly indicates 
otherwise.

      1.2.   AFFILIATE.  "Affiliate" shall mean, with respect to any Person, 
any Person or Person that, directly or indirectly, controls, or is controlled 
by or is under common control with such Person.  For the purpose of this 
definition, "control" (including the terms "controlling", "controlled by" and 
"under common control with"), as used with respect to any Person, means the 
possession, directly or indirectly, of the power to direct or cause the 
direction of the management or policies of such Person, whether through the 
ownership of voting securities or by contract or agency or otherwise.

      1.3.   AWARD LIMIT.  "Award Limit" shall mean 100,000 shares of Common 
Stock, as adjusted pursuant to Section 8.3.

      1.4.   BOARD.  "Board" shall mean the Board of Directors of the Company.


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      1.5.   CODE.  "Code" shall mean the Internal Revenue Code of 1986, as 
amended.

      1.6.   COMMITTEE.  "Committee" shall mean the Compensation Committee of 
the Board, or another committee of the Board, appointed as provided in Section 
7.1.

      1.7.   COMMON STOCK.  "Common Stock" shall mean the common stock of the 
Company, $.005 par value per share, and any equity security of the Company 
issued or authorized to be issued in the future, but excluding any preferred 
stock and any warrants, options or other rights to purchase Common Stock.  Debt 
securities of the Company convertible into Common Stock shall be deemed equity 
securities of the Company.

      1.8.   COMPANY.  "Company" shall mean Eco Soil Systems, Inc., a Nebraska 
corporation.

      1.9.   CORPORATE TRANSACTION.  "Corporate Transaction" shall mean any of 
the following shareholder-approved transactions to which the Company is a party:

      (a)   a merger or consolidation in which the Company is not the 
surviving entity, except for a transaction the principal purpose of which is 
to change the State in which the Company is incorporated, to form a holding 
company or to effect a similar reorganization as to form whereupon this Plan 
and all Options are assumed by the successor entity;

      (b)   the sale, transfer, exchange or other disposition of all or 
substantially all of the assets of the Company, in complete liquidation or 
dissolution of the Company in a transaction not covered by the exceptions to 
clause (a), above; or

      (c)   any reverse merger in which the Company is the surviving entity 
but in which securities possessing more than fifty percent (50%) of the total 
combined voting power of the Company's outstanding securities are transferred 
or issued to a person or persons different from those who held such 
securities immediately prior to such merger.

      1.10.   DIRECTOR.  "Director" shall mean a member of the Board.

      1.11.   DISABILITY.  "Disability" shall mean, with respect to any 
Optionee, (i) the suffering of any mental or physical illness, disability or 
incapacity that shall in all material aspects preclude such Optionee from 
performing his or her directorial, employment or consultant duties, or (ii) 
the absence of such Optionee from his or her directorial, employment or 
consultant duties by reason of any mental or physical illness, disability or 
incapacity for a period of six (6) months during any twelve (12) month 
period; provided, however, in either case, that such illness, disability or 
incapacity shall be 


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reasonably determined to be of a permanent nature by the Committee (or the 
Board in the case of Options granted to Independent Directors).

      1.12.   EMPLOYEE.  "Employee" shall mean any officer or other employee 
(as defined in accordance with Section 3401(c) of the Code) of the Company, 
or of any corporation which is a Subsidiary.

      1.13.   EXCHANGE ACT.  "Exchange Act" shall mean the Securities 
Exchange Act of 1934, as amended.

      1.14.   FAIR MARKET VALUE.  "Fair Market Value" of a share of Common 
Stock as of a given date shall be (i) the closing price of a share of Common 
Stock on the principal exchange on which shares of Common Stock are then 
trading, if any (or as reported on any composite index which includes such 
principal exchange), on the trading day previous to such date, or if shares 
were not traded on the trading day previous to such date, then on the next 
preceding date on which a trade occurred; or (ii) if Common Stock is not 
traded on an exchange but is quoted on NASDAQ or a successor quotation 
system, the mean between the closing representative bid and asked prices for 
the Common Stock on the trading day previous to such date as reported by 
NASDAQ or such successor quotation system; or (iii) if Common Stock is not 
publicly traded on an exchange and not quoted on NASDAQ or a successor 
quotation system, the Fair Market Value of a share of Common Stock shall be 
established by the Committee (or the Board in the case of Options granted to 
Independent Directors) acting in good faith, giving predominate weight to the 
earnings history, book value and prospects of the Company in light of market 
conditions generally.

      1.15.   INCENTIVE STOCK OPTION.  "Incentive Stock Option" shall mean an 
option which conforms to the applicable provisions of Section 422 of the Code 
and which is designated as an Incentive Stock Option by the Committee.

      1.16.   INDEPENDENT DIRECTOR.  "Independent Director" shall mean a 
member of the Board who is not an Employee of the Company.

      1.17.   NON-QUALIFIED STOCK OPTION.  "Non-Qualified Stock Option" shall 
mean an Option which is not designated as an Incentive Stock Option by the 
Committee.

      1.18.   OPTION.  "Option" shall mean a stock option granted under 
Article III of this Plan.  An Option granted under this Plan shall, as 
determined by the Committee, be either a Non-Qualified Stock Option or an 
Incentive Stock Option; provided, however that Options granted to Independent 
Directors and consultants shall be Non-Qualified Stock Options.


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      1.19.   OPTION SHARES.  "Option Shares" shall mean shares of Common 
Stock acquired by Optionees through the exercise of Options under this Plan.

      1.20.   OPTIONEE.  "Optionee" shall mean an Employee, consultant or 
Independent Director granted an Option under this Plan.

      1.21.   PERSON.  "Person" shall mean a corporation, an association, a 
partnership, a trust, a limited liability company, an organization, a 
business or an individual.

      1.22.   PLAN.  "Plan" shall mean The 1998 Stock Option Plan of Eco Soil 
Systems, Inc.

      1.23.   PUBLIC OFFERING.  "Public Offering" shall mean the registration 
of an offering of shares of Common Stock under the Securities Act which 
becomes effective (other than by a registration on Form S-8 or any successor 
or similar forms).

      1.24.   QDRO.  "QDRO" shall mean a qualified domestic relations order 
as defined by the Code or Title I of the Employee Retirement Income Security 
Act of 1974, as amended, or the rules thereunder.

      1.25.   RELATED PERSON.  "Related Person" shall mean (a) in the event 
of a Person's death, such Person's executors, administrators, testamentary 
trustees, legatees or beneficiaries or the executors, administrators, 
testamentary trustees, legatees or beneficiaries of a Person who has become a 
holder of Options or Option Shares in accordance with the terms of this Plan; 
or (b) a revocable trust or custodianship the beneficiaries of which may 
include only such Person, spouse or lineal descendants by blood or adoption.

      1.26.   RULE 16b-3.  "Rule 16b-3" shall mean that certain Rule 16b-3 
under the Exchange Act, as such Rule may be amended from time to time.

      1.27.   SECURITIES ACT.  "Securities Act" shall mean the Securities Act 
of 1933, as amended.

      1.28.   SUBSIDIARY.  "Subsidiary" shall mean any corporation in an 
unbroken chain of corporations beginning with the Company if each of the 
corporations other than the last corporation in the unbroken chain then owns 
stock possessing fifty percent (50%) or more of the total combined voting 
power of all classes of stock in one (1) of the other corporations in such 
chain.


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      1.29.   TERMINATION OF CONSULTANCY.  "Termination of Consultancy" shall 
mean the time when the engagement of an Optionee as a consultant to the 
Company or a Subsidiary is terminated for any reason, with or without cause, 
including, but not by way of limitation, by resignation, discharge, death, 
Disability or retirement; but excluding terminations where there is a 
simultaneous commencement of employment with the Company or any Subsidiary.  
The Committee, in its absolute discretion, shall determine the effect of all 
matters and questions relating to Termination of Consultancy, including, but 
not by way of limitation, the question of whether a Termination of 
Consultancy resulted from a discharge for good cause, and all questions of 
whether particular leaves of absence constitute Terminations of Consultancy.  
Notwithstanding any other provision of this Plan, the Company or any 
Subsidiary has an absolute and unrestricted right to terminate a consultant's 
service at any time for any reason whatsoever, with or without cause, except 
to the extent expressly provided otherwise in writing.

      1.30.   TERMINATION OF DIRECTORSHIP.  "Termination of Directorship" 
shall mean the time when an Optionee who is an Independent Director ceases to 
be a Director for any reason, including, but not by way of limitation, a 
termination by resignation, failure to be elected, death, Disability or 
retirement.  The Board, in its sole and absolute discretion, shall determine 
the effect of all matters and questions relating to Termination of 
Directorship with respect to Independent Directors.

      1.31.   TERMINATION OF EMPLOYMENT.  "Termination of Employment" shall 
mean the time when the employee-employer relationship between an Optionee and 
the Company or any Subsidiary is terminated for any reason, with or without 
cause, including, but not by way of limitation, a termination by resignation, 
discharge, death, Disability or retirement; but excluding (i) terminations 
where there is a simultaneous reemployment or continuing employment of an 
Optionee by the Company or any Subsidiary, (ii) at the discretion of the 
Committee, terminations which result in a temporary severance of the 
employee-employer relationship, and (iii) at the discretion of the Committee, 
terminations which are followed by the simultaneous establishment of a 
consulting relationship by the Company or a Subsidiary with the former 
employee.  The Committee, in its absolute discretion, shall determine the 
effect of all matters and questions relating to Termination of Employment, 
including, but not by way of limitation, the question of whether a 
Termination of Employment resulted from a discharge for good cause, and all 
questions of whether particular leaves of absence constitute Terminations of 
Employment; provided, however, that, unless otherwise determined by the 
Committee in its discretion, a leave of absence, change in status from an 
employee to an independent contractor or other change in the 
employee-employer relationship shall constitute a Termination of Employment 
if, and to the extent that, such leave of absence, change in status or other 
change interrupts employment for the purposes of Section 422(a)(2) of the 
Code and the then applicable regulations and revenue rulings under said 
Section.  Notwithstanding any other provision of this Plan, the Company or 
any Subsidiary has an absolute and unrestricted right to terminate an 
Employee's employment at any time for any reason whatsoever, with or without 
cause, except to the extent expressly provided otherwise in writing.


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1.32.   TERMINATION FOR CAUSE.  "Termination for Cause" shall mean the time 
when the Independent Director-employer, employee-employer or 
consultant-employer relationship between an Optionee and the Company or any 
Subsidiary is terminated for cause, as termination for cause is defined in 
the Optionee's directorial, employment or consultancy agreement; provided 
however, that if termination for cause is not therein defined, it shall have 
such meaning, in conformance with applicable law, as the Committee (or the 
Board in the case of termination for cause of an Independent Director) shall 
determine is appropriate.

                                 ARTICLE II.

                            SHARES SUBJECT TO PLAN

      2.1.   SHARES SUBJECT TO PLAN.

      (a)   The shares of stock subject to Options shall be Common Stock.  
The aggregate number of such shares which may be issued upon exercise of such 
options under the Plan shall be 100,000.  The shares of Common Stock of the 
Company issuable upon exercise of such options may be either previously 
authorized but unissued shares or treasury shares.

      (b)   The maximum number of shares which may be subject to Options 
granted under the Plan to any individual in any fiscal year of the Company 
shall not exceed the Award Limit.  To the extent required by Section 162(m) 
of the Code, shares subject to Options which are canceled continue to be 
counted against the Award Limit and if, after grant of an Option, the price 
of shares subject to such Option is reduced, the transaction is treated as a 
cancellation of the Option and a grant of a new Option and both the Option 
deemed to be canceled and the Option deemed to be granted are counted against 
the Award Limit.

      2.2.   ADD-BACK OF OPTIONS.  If any Option to acquire shares of Common 
Stock under this Plan expires or is canceled without having been fully 
exercised, the number of shares subject to such Option but as to which such 
Option was not exercised prior to its expiration, cancellation or exercise 
may again be available for the granting of Options hereunder, subject to the 
limitations of Section 2.1.  Furthermore, any shares subject to Options which 
are adjusted pursuant to Section 8.3 and become exercisable with respect to 
shares of stock of another corporation shall be considered canceled and may 
again be available for the granting of Options hereunder, subject to the 
limitations of Section 2.1.  Shares of Common Stock which are delivered by 
the Optionee or withheld by the Company upon the exercise of any Option under 
this Plan, in payment of the exercise price thereof, may again be available 
for the granting of Options hereunder, subject to the limitations of Section 
2.1.  Notwithstanding the provisions of this Section 2.2, no shares of Common 
Stock may again be available for the granting of Options if such action would 
cause an Incentive Stock Option to fail to qualify as an incentive stock 


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option under Section 422 of the Code.

                                ARTICLE III.

                             GRANTING OF OPTIONS

      3.1.   ELIGIBILITY.  Any Independent Director, Employee or consultant 
selected by the Committee (or the Board in the case of Options granted to 
Independent Directors) pursuant to Section 3.4(a)(i) shall be eligible to be 
granted an Option.  

      3.2.   DISQUALIFICATION FOR STOCK OWNERSHIP.  No person may be granted 
an Incentive Stock Option under this Plan if such person, at the time the 
Incentive Stock Option is granted, owns stock possessing more than ten 
percent (10%) of the total combined voting power of all classes of stock of 
the Company or any then existing Subsidiary unless such Incentive Stock 
Option conforms to the applicable provisions of Section 422 of the Code.

      3.3.   QUALIFICATION OF INCENTIVE STOCK OPTIONS.  No Incentive Stock 
Option shall be granted to any person who is not an Employee.

      3.4.   GRANTING OF OPTIONS.

      (a)   The Committee (or the Board in the case of Options granted to 
Independent Directors) shall from time to time, in its absolute discretion, 
and subject to applicable limitations of this Plan:

            (i)   Determine which Employees are key Employees and select from 
    among the Independent Directors, key Employees and consultants (including 
    Independent Directors, Employees and consultants who have previously 
    received Options or other awards under this Plan) such of them as in its 
    opinion should be granted Options;

            (ii)  Subject to the Award Limit, determine the number of shares 
    to be subject to such Options granted to the selected Independent 
    Directors, key Employees and consultants;

            (iii) Subject to Section 3.2, determine whether such Options are 
    to be Incentive Stock Options or Non-Qualified Stock Options and whether 
    such Options are to qualify as performance-based compensation as 
    described in Section 162(m)(4)(C) of the Code; and

            (iv)   Determine the terms and conditions of such Options, 
    consistent with this Plan; provided, however, that the terms and 
    conditions of Options intended to qualify as performance-based 
    compensation as described in 


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    Section 162(m)(4)(C) of the Code shall include, but not be limited to, 
    such terms and conditions as may be necessary to meet the applicable 
    provisions of Section 162(m) of the Code.

      (b)   Upon the selection of an Independent Director, key Employee or 
consultant to be granted an Option, the Committee (or the Board in the case 
of Options granted to Independent Directors) shall instruct the Secretary of 
the Company to issue the Option and may impose such conditions on the grant 
of the Option as it deems appropriate.  Without limiting the generality of 
the preceding sentence, the Committee (or the Board in the case of Options 
granted to Independent Directors) may, in its discretion and on such terms as 
it deems appropriate, require as a condition on the grant of an Option to an 
Independent Director, Employee or consultant that such Independent Director, 
Employee or consultant surrender for cancellation some or all of the 
unexercised Options or other rights which have been previously granted to 
such Independent Director, Employee or consultant under this Plan or 
otherwise.  An Option, the grant of which is conditioned upon such surrender, 
may have an option price lower (or higher) than the exercise price of such 
surrendered Option or other award, may cover the same (or a lesser or 
greater) number of shares as such surrendered Option or other award, may 
contain such other terms as the Committee (or the Board in the case of 
Options granted to Independent Directors) deems appropriate, and shall be 
exercisable in accordance with its terms, without regard to the number of 
shares, price, exercise period or any other term or condition of such 
surrendered Option or other award. 

      (c)   Any Incentive Stock Option granted under this Plan may be 
modified by the Committee to disqualify such option from treatment as an 
"incentive stock option" under Section 422 of the Code.

      (d)   Each Independent Director shall be automatically granted an 
Option (an "Initial Grant") to purchase 10,000 Shares upon the date on which 
such person first becomes a Director, whether through election by the 
shareholders of the Company or appointment by the Board to fill a vacancy.  
Options granted under this section 3.4(c)(ii) shall become vested and thereby 
exercisable with respect to 33.33% of such Initial Grant on the twelve month 
anniversary date of such Initial Grant and with respect to 33.33% at each 
successive anniversary date; provided, however, an unvested portion of an 
Initial Grant shall only vest so long as the Independent Director remains a 
Director on the date such portion vests.

      (e)   Each Independent Director shall automatically receive, on the 
date of each Annual Meeting of Shareholders, an Option to purchase 3,000 
Shares of the Company's Common Stock, such Option to become exercisable six 
months subsequent to the date of grant; provided, however, that such Option 
shall only be granted to Independent Directors who have served since the date 
of the last Annual Meeting of Shareholders and will continue to serve after 
the date of grant of such Option.


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                            ARTICLE IV.

                          TERMS OF OPTIONS

      4.1.   OPTION AGREEMENT.  Each Option shall be evidenced by a written 
Stock Option Agreement, which shall be executed by the Optionee and an 
authorized officer of the Company and which shall contain such terms and 
conditions as the Committee (or the Board in the case of Options granted to 
Independent Directors) shall determine, consistent with this Plan.  Stock 
Option Agreements evidencing Options intended to qualify as performance-based 
compensation as described in Section 162(m)(4)(C) of the Code shall contain 
such terms and conditions as may be necessary to meet the applicable 
provisions of Section 162(m) of the Code.  Stock Option Agreements evidencing 
Incentive Stock Options shall contain such terms and conditions as may be 
necessary to meet the applicable provisions of Section 422 of the Code.

      4.2.   OPTION PRICE.  The price per share of the shares subject to each 
Option shall be set by the Committee (or the Board in the case of Options 
granted to Independent Directors); provided, however, that:

      (a)    Unless otherwise permitted by applicable securities laws, such 
price shall be not less than eighty-five percent (85%) of the Fair Market 
Value of the stock at the time the option is granted, except that the price 
shall be one hundred and ten percent (110%) of the Fair Market Value of the 
stock in the case of any person possessing more than ten percent (10%) of the 
total combined voting power of all classes of stock of the Company or its 
Subsidiary;

      (b)   In the case of Incentive Stock Options and Options intended to 
qualify as performance-based compensation as described in Section 
162(m)(4)(C) of the Code, such price shall not be less than one hundred 
percent (100%) of the Fair Market Value of a share of Common Stock on the 
date the Option is granted; and

      (c)   In the case of Incentive Stock Options granted to an individual 
then owning (within the meaning of Section 424(d) of the Code) more than ten 
percent (10%) of the total combined voting power of all classes of stock of 
the Company or any Subsidiary such price shall not be less than one hundred 
and ten percent (110%) of the Fair Market Value of a share of Common Stock on 
the date the Option is granted.

      4.3.   OPTION TERM.  The term of an Option shall be set by the 
Committee (or the Board in the case of Options granted to Independent 
Directors) in its discretion; provided, however, that:

      (a)   No Option may have a term that extends beyond the expiration of 
ten (10) years from the date the Option was granted;


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      (b)   In the case of Incentive Stock Options, the term shall not be 
more than ten (10) years from the date the Incentive Stock Option is granted, 
or five (5) years from such date if the Incentive Stock Option is granted to 
an individual then owning (within the meaning of Section 424(d) of the Code) 
more than ten percent (10%) of the total combined voting power of all classes 
of stock of the Company or any Subsidiary;

      (c)   Except as limited by requirements of Section 422 of the Code and 
regulations and rulings thereunder applicable to Incentive Stock Options, the 
Committee (or the Board in the case of Options granted to Independent 
Directors) may extend the term of any outstanding Option in connection with 
any Termination of Directorship, Termination of Employment or Termination of 
Consultancy of the Optionee, or amend any other term or condition of such 
Option relating to such a termination; and

      (d)   Unless otherwise permitted by applicable securities laws, in the 
event of an Optionee's Termination of Directorship, Termination of Employment 
or Termination of Consultancy for any reason except death, Disability or 
Termination for Cause, the Optionee shall have at least thirty (30) days from 
the date of such Termination of Directorship, Termination of Employment or 
Termination of Consultancy to exercise the Option, and in the event of an 
Optionee's Termination of Directorship, Termination of Employment or 
Termination of Consultancy due to the Optionee's death or Disability, the 
Optionee shall have at least six (6) months from the date of such Termination 
of Directorship, Termination of Employment or Termination of Consultancy to 
exercise the Option.  Notwithstanding the forgoing, if an Optionee's 
Termination of Directorship, Termination of Employment or Termination of 
Consultancy also qualifies as a Termination for Cause, the Company, in its 
discretion, may terminate the Optionee's right to exercise his or her Options 
on the date of such termination or such other time as the Committee (or the 
Board in the case of Options granted to Independent Directors), in its 
discretion, shall deem appropriate.

      4.4.   OPTION VESTING.

      (a)   The period during which the right to exercise an Option in whole 
or in part vests in the Optionee shall be set by the Committee (or the Board 
in the case of Options granted to Independent Directors) and the Committee 
(or the Board in the case of Options granted to Independent Directors) may 
determine that an Option may not be exercised in whole or in part for a 
specified period after it is granted; provided, however, that, subject to 
Section 4.4(b), (i) unless otherwise permitted by applicable securities laws, 
each Option shall become exercisable no later than five (5) years after such 
Option is granted and such Option shall become exercisable with respect to at 
least twenty percent (20%) of the shares of Common Stock subject to such 
Option, as determined by the Committee (or the Board in the case of Options 
granted to Independent Directors) in its sole discretion, on each anniversary 
of the date of the grant of such Option; (ii) unless the Committee (or the 
Board in the case of Options granted to Independent Directors) otherwise 
provides in the terms of the Stock Option Agreement or this Plan otherwise so 
dictates, no Option shall be exercisable by any Optionee who is then subject 
to Section 16 


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of the Exchange Act within the period ending six months and one day after the 
date the Option is granted; and (iii) upon the transfer of more than fifty 
percent (50%) of Common Stock to a Person who is not an Affiliate of the 
Company during the term of the Option, immediately upon such transfer, each 
outstanding Option shall automatically become fully exercisable for all of 
the shares of Common Stock at the time subject to such Option; provided, 
further, that Options may become fully exercisable, subject to reasonable 
conditions such as continued directorship, employment or consultancy, at any 
time or during any period established by the Committee (or the Board in the 
case of Options granted to Independent Directors).

      (b)   No portion of an Option which is unexercisable at Termination of 
Directorship, Termination of Employment or Termination of Consultancy shall 
thereafter become exercisable, except as may be otherwise provided by the 
Committee (or the Board in the case of Options granted to Independent 
Directors) either in the Stock Option Agreement or by action of the Committee 
(or the Board in the case of Options granted to Independent Directors) 
following the grant of the Option. 

      (c)   To the extent that the aggregate Fair Market Value of stock with 
respect to which "incentive stock options" (within the meaning of Section 422 
of the Code, but without regard to Section 422(d) of the Code) are 
exercisable for the first time by an Optionee during any calendar year (under 
the Plan and all other incentive stock option plans of the Company and any 
Subsidiary) exceeds $100,000, such Options shall be treated as Non-Qualified 
Options to the extent required by Section 422 of the Code.  The rule set 
forth in the preceding sentence shall be applied by taking Options into 
account in the order in which they were granted.  For purposes of this 
Section 4.4(c), the Fair Market Value of stock shall be determined as of the 
time the Option with respect to such stock is granted.

      4.5.   CONSIDERATION.  In consideration of the granting of an Option, 
the Optionee shall agree, in the written Stock Option Agreement, to remain in 
the employ (or to consult for or serve as an Independent Director, as 
applicable) of the Company or any Subsidiary for a period of at least one (1) 
year (or such shorter period as may be fixed in the Stock Option Agreement or 
by action of the Committee (or the Board in the case of Options granted to 
Independent Directors) following grant of the Option) after the Option is 
granted (or, in the case of an Independent Director, until the next annual 
meeting of the shareholders of the Company).  Nothing in this Plan or in any 
Stock Option Agreement hereunder shall confer upon any Optionee any right to 
continue in the employ (or to consult for or serve as an Independent 
Director, as applicable) of the Company or any Subsidiary or shall interfere 
with or restrict in any way the rights of the Company or any Subsidiary, 
which are hereby expressly reserved, to discharge any Optionee at any time 
for any reason whatsoever, with or without good cause.

      4.6.   FINANCIAL STATEMENTS.  To the extent required by applicable 
securities laws, each Optionee shall receive financial statements of the 
Company at least annually.


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                                ARTICLE V.

                            EXERCISE OF OPTIONS

      5.1.   PARTIAL EXERCISE.  An exercisable Option may be exercised in 
whole or in part.  However, an Option shall not be exercisable with respect 
to fractional shares and the Committee (or the Board in the case of Options 
granted to Independent Directors) may require that, by the terms of the 
Option, a partial exercise be with respect to a minimum number of shares.

      5.2.   MANNER OF EXERCISE.  All or a portion of an exercisable Option 
shall be deemed exercised upon delivery of all of the following to the 
Secretary of the Company or such Secretary's office:

      (a)   A written notice complying with the applicable rules established 
by the Committee (or the Board in the case of Options granted to Independent 
Directors) stating that the Option, or a portion thereof, is exercised.  The 
notice shall be signed by the Optionee or other person then entitled to 
exercise the Option or such portion;

      (b)   Such representations and documents as the Committee (or the Board 
in the case of Options granted to Independent Directors), in its absolute 
discretion, deems necessary or advisable to effect compliance with all 
applicable provisions of the Securities Act and any other federal or state 
securities laws or regulations.  The Committee (or the Board in the case of 
Options granted to Independent Directors) may, in its absolute discretion, 
also take whatever additional actions it deems appropriate to effect such 
compliance including, without limitation, placing legends on share 
certificates and issuing stop-transfer notices to agents and registrars;

      (c)   In the event that the Option shall be exercised pursuant to 
Section 8.1 by any person or persons other than the Optionee, appropriate 
proof of the right of such person or persons to exercise the Option; and

      (d)   Full cash payment to the Secretary of the Company for the shares 
and for payment of any applicable withholding or other applicable employment 
taxes with respect to which the Option, or portion thereof, is exercised.  
However, the Committee (or the Board in the case of Options granted to 
Independent Directors), may in its discretion (i) allow a delay in payment up 
to thirty (30) days from the date the Option, or portion thereof, is 
exercised; (ii) allow payment, in whole or in part, through the delivery of 
shares of Common Stock owned by the Optionee, duly endorsed for transfer to 
the Company with a Fair Market Value on the date of delivery equal to the 
aggregate exercise price of the Option or exercised portion thereof; (iii) 
allow payment, in whole or in part, through the surrender of shares of Common 
Stock then issuable upon exercise of the Option having a Fair Market Value on 
the date of Option exercise equal to the aggregate exercise price of the 
Option or exercised portion thereof; (iv) allow payment, in whole or 


                                          12
<PAGE>


in part, through the delivery of property of any kind which constitutes good 
and valuable consideration; (v) allow payment, in whole or in part, through 
the delivery of a full recourse promissory note bearing interest (at no less 
than such rate as shall then preclude the imputation of interest under the 
Code) and payable upon such terms as may be prescribed by the Committee (or 
the Board in the case of Options granted to Independent Directors); (vi) 
allow payment, in whole or in part, through the delivery of a notice that the 
Optionee has placed a market sell order with a broker with respect to shares 
of Common Stock then issuable upon exercise of the Option, and that the 
broker has been directed to pay a sufficient portion of the net proceeds of 
the sale to the Company in satisfaction of the Option exercise price and any 
applicable withholding or other employment taxes; or (vii) allow payment 
through any combination of the consideration provided in the foregoing 
subparagraphs (ii), (iii), (iv), (v) and (vi).  In the case of a promissory 
note, the Committee (or the Board in the case of Options granted to 
Independent Directors) may also prescribe the form of such note and the 
security to be given for such note.  The Option may not be exercised, 
however, by delivery of a promissory note or by a loan from the Company when 
or where such loan or other extension of credit is prohibited by law.

      5.3.   CONDITIONS TO ISSUANCE OF STOCK CERTIFICATES.  The Company shall 
not be required to issue or deliver any certificate or certificates for 
shares of stock purchased upon the exercise of any Option or portion thereof 
prior to fulfillment of all of the following conditions:

      (a)   The admission of such shares to listing on all stock exchanges, 
if any, on which such class of stock is then listed;

      (b)   The completion of any registration or other qualification of such 
shares under any state or federal law, or under the rulings or regulations of 
the Securities and Exchange Commission or any other governmental regulatory 
body which the Committee or the Board shall, in its absolute discretion, deem 
necessary or advisable;

      (c)   The obtaining of any approval or other clearance from any state 
or federal governmental agency which the Committee or the Board shall, in its 
absolute discretion, determine to be necessary or advisable;

      (d)   The lapse of such reasonable period of time following the 
exercise of the Option as the Committee or the Board may establish from time 
to time for reasons of administrative convenience; and

      (e)   The receipt by the Company of full payment for such shares, 
including payment of any applicable withholding tax.

      5.4.   RIGHTS AS SHAREHOLDERS.  The holders of Options shall not be, 
nor have any of the rights or privileges of, shareholders of the Company in 
respect of any shares purchasable upon the exercise of any part of an Option 
unless and until certificates 


                                       13
<PAGE>


representing such shares have been issued by the Company to such holders.

                                 ARTICLE VI.

            RIGHTS AND RESTRICTIONS WITH RESPECT TO OPTION SHARES

      6.1.   TRANSFER RESTRICTIONS.  No Optionee may transfer, assign, pledge 
or otherwise encumber any Option Shares except as expressly provided 
otherwise in this Article VI; provided, however, that Option Shares may be 
transferred at any time to a Related Person, provided that the Related Person 
agrees in writing to be bound by the terms of this Plan.  

      6.2.   COMPANY'S RIGHT OF FIRST REFUSAL.  

      (a)   An Optionee (a "Proposed Seller") shall be permitted to transfer, 
assign, or sell any Option Shares in an arm's length transaction (a "Proposed 
Transfer"); provided, however, such Optionee shall first offer to sell such 
Option Shares to the Company under the procedure described in paragraphs (b) 
and (c) of this Section 6.2.

      (b)   Prior to consummating any Proposed Transfer, the Proposed Seller 
shall first notify the Company in writing that such Proposed Seller has 
received a bona fide written offer to purchase Option Shares (a "Purchase 
Offer") and shall offer to sell to the Company all Option Shares subject to 
the Purchase Offer upon the terms and conditions (including credit terms, if 
any) set forth in such Purchase Offer.  Such notice (the "Offer Notice") 
shall set forth:  (A) the number of Option Shares proposed to be transferred, 
(B) the name and address of the Proposed Seller and the proposed purchaser 
(the "Proposed Purchaser"), and (C) the proposed amount of consideration and 
all other applicable terms and conditions as set forth in, and shall be 
accompanied by a copy of, the Purchase Offer.

      (c)   (i)   The Company shall have the option for a period of fifteen 
(15) days following the Company's receipt of the Offer Notice to agree to 
purchase all of the Option Shares subject to the Purchase Offer, upon the 
terms and conditions specified therein.

            (ii)  In the event the Company agrees to purchase Option Shares 
pursuant to and in accordance with this Section 6.2, such purchase shall 
occur at the principal office of the Company ten (10) days following the 
expiration of the fifteen (15) day period specified in subparagraph (i) of 
this paragraph (c).  In no event shall the Proposed Seller be required to 
transfer any Option Shares to the Company pursuant to this Section 6.2 unless 
the Company purchases all of the Option Shares subject the Purchase Offer on 
the terms and at the price stated therein and within the time periods 
specified herein.  


                                          14
<PAGE>


      (d)   In the event the Company does not agree to purchase all of the 
Option Shares offered to the Company by a Proposed Seller pursuant to this 
Section 6.2, then the Proposed Seller shall have the right for a period of 
thirty (30) days after the termination of the Company's right to purchase 
such Option Shares (or after waiver by the Company of its option to purchase 
such Option Shares) to transfer to the Proposed Purchaser all, but not less 
than all, of such Option Shares in the manner and on the terms and conditions 
specified in the Purchase Offer; provided, however, the Proposed Purchaser 
shall agree in writing to be bound by this Plan. 

      6.3.   LAPSE OF STOCK RESTRICTIONS AND RIGHTS.  The provisions set 
forth in Sections 6.1 and 6.2 shall terminate and cease to be of any further 
force or effect upon the completion of a Public Offering, or a series of 
Public Offerings, which result in public ownership of Common Stock of the 
Company possessing at least twenty percent (20%) of the total combined voting 
power of such Common Stock (or such lesser percentage as dictated by 
applicable securities laws).

      6.4.   OWNERSHIP AND TRANSFER RESTRICTIONS.  The Committee (or the 
Board in the case of Options granted to Independent Directors), in its 
absolute discretion, may impose additional restrictions on the ownership and 
transferability of the shares purchasable upon the exercise of an Option as 
it deems appropriate.  Any such restriction shall be set forth in the 
respective Stock Option Agreement and may be referred to on the certificates 
evidencing such shares.  

      6.5.   LEGEND.  Each certificate representing Option Shares shall be 
endorsed with the following legend, which legend shall be removed upon 
termination of the stock restrictions set forth in this Article 6.

     THE SALE OR TRANSFER OF THE SECURITIES REPRESENTED BY THIS 
     CERTIFICATE IS SUBJECT TO THE TERMS AND CONDITIONS OF A CERTAIN 
     1998 STOCK OPTION PLAN OF ECO SOIL SYSTEMS, INC. COPIES OF SUCH 
     STOCK OPTION PLAN MAY BE OBTAINED UPON WRITTEN REQUEST TO THE 
     SECRETARY OF THE CORPORATION.

      6.6.   DISPOSITION OF SHARES.  Notwithstanding and in addition to the 
foregoing, each Optionee shall be required to give the Company prompt notice 
of any disposition of shares of Common Stock acquired by exercise of an 
Incentive Stock Option within (i) two (2) years from the date of granting 
such Option to such Optionee or (ii) one (1) year after the transfer of such 
shares to such Optionee.  Certificates evidencing shares acquired by exercise 
of an Incentive Stock Option shall refer to such requirement to give prompt 
notice of disposition.


                                     15

<PAGE>
                                ARTICLE VII.

                               ADMINISTRATION

      7.1.   COMPENSATION COMMITTEE.  Prior to the Company's initial 
registration of Common Stock under Section 12 of the Exchange Act, the 
Compensation Committee shall consist of the entire Board, provided, however, 
that the Board may appoint a Committee of its members to administer this Plan 
at any time prior to such registration.  Following such registration, the 
Compensation Committee (or another committee of the Board assuming the 
functions of the Committee under this Plan) shall consist solely of two or 
more Independent Directors appointed by and holding office at the pleasure of 
the Board, each of whom is both a "non-employee director" as defined by Rule 
16(b)-3 and an "outside director" for purposes of Section 162(m) of the Code. 
 Appointment of Committee members shall be effective upon acceptance of 
appointment.  Committee members may resign at any time by delivering written 
notice to the Board.  Vacancies in the Committee may be filled by the Board.

      7.2.   DUTIES AND POWERS OF COMMITTEE.  It shall be the duty of the 
Committee to conduct the general administration of this Plan in accordance 
with its provisions.  The Committee shall have the power to interpret this 
Plan and the agreements pursuant to which Options are granted or awarded, and 
to adopt such rules for the administration, interpretation, and application 
of this Plan as are consistent therewith and to interpret, amend or revoke 
any such rules.  Notwithstanding the foregoing, the full Board, acting by a 
majority of its members in office, shall conduct the general administration 
of the Plan with respect to Options granted to Independent Directors.  Any 
such grant or award under this Plan need not be the same with respect to each 
Optionee. Any such interpretations and rules with respect to Incentive Stock 
Options shall be consistent with the provisions of Section 422 of the Code.  
In its absolute discretion, the Board may at any time and from time to time 
exercise any and all rights and duties of the Committee under this Plan 
except with respect to matters which under Rule 16b-3 or Section 162(m) of 
the Code, or any regulations or rules issued thereunder, are required to be 
determined in the sole discretion of the Committee.

      7.3.   MAJORITY RULE; UNANIMOUS WRITTEN CONSENT.  The Committee shall 
act by a majority of its members in attendance at a meeting at which a quorum 
is present or by a memorandum or other written instrument signed by all 
members of the Committee.

      7.4.   COMPENSATION; PROFESSIONAL ASSISTANCE; GOOD FAITH ACTIONS.  
Members of the Committee shall receive such compensation for their services 
as members as may be determined by the Board.  All expenses and liabilities 
which members of the Committee incur in connection with the administration of 
this Plan shall be borne by the Company.  The Committee may, with the 
approval of the Board, employ attorneys, consultants, accountants, 
appraisers, brokers, or other persons.  The Committee, the Company and the 
Company's officers and Directors shall be entitled to rely upon the advice, 
opinions or valuations of any such persons.  All actions taken and all 


                                      16
<PAGE>


interpretations and determinations made by the Committee or the Board in good 
faith shall be final and binding upon all Optionees, the Company and all 
other interested persons.  No members of the Committee or Board shall be 
personally liable for any action, determination or interpretation made in 
good faith with respect to this Plan or Options, and all members of the 
Committee and the Board shall be fully protected by the Company in respect of 
any such action, determination or interpretation.

                               ARTICLE VIII.

                         MISCELLANEOUS PROVISIONS

      8.1.   NOT TRANSFERABLE.  Options under this Plan may not be sold, 
pledged, assigned, or transferred in any manner other than by will or the 
laws of descent and distribution or pursuant to a QDRO, unless and until such 
options have been exercised, or the shares underlying such Options have been 
issued, and all restrictions applicable to such shares have lapsed.  No 
Option or interest or right therein shall be liable for the debts, contracts 
or engagements of the Optionee or the Optionee's successors in interest or 
shall be subject to disposition by transfer, alienation, anticipation, 
pledge, encumbrance, assignment or any other means whether such disposition 
be voluntary or involuntary or by operation of law by judgment, levy, 
attachment, garnishment or any other legal or equitable proceedings 
(including bankruptcy), and any attempted disposition thereof shall be null 
and void and of no effect, except to the extent that such disposition is 
permitted by the preceding sentence.

      During the lifetime of the Optionee, only such Optionee may exercise an 
Option (or any portion thereof) granted to such Optionee under the Plan, 
unless the Option has been disposed of pursuant to a QDRO.  After the death 
of the Optionee, any exercisable portion of an Option may, prior to the time 
when such portion becomes unexercisable under the Plan or the applicable 
Stock Option Agreement or other agreement, be exercised by the Optionee's 
personal representative or by any person empowered to do so under the 
deceased Optionee's will or under the then applicable laws of descent and 
distribution.

      8.2.   AMENDMENT, SUSPENSION OR TERMINATION OF THIS PLAN.  Except as 
otherwise provided in this Section 8.2, this Plan may be wholly or partially 
amended or otherwise modified, suspended or terminated at any time or from 
time to time by the Board or the Committee.  However, without approval of the 
Company's shareholders given within twelve months before or after the action 
by the Board or the Committee, no action of the Board or the Committee may, 
except as provided in Section 8.3, increase the limits imposed in Section 2.1 
on the maximum number of shares which may be issued under this Plan or modify 
the Award Limit, and no action of the Board or the Committee may be taken 
that would otherwise require shareholder approval as a matter of applicable 
law, regulation or rule.  No amendment, suspension or termination of this 
Plan shall, without the consent of the holder of Options, alter or impair any 
rights or obligations 


                                        17
<PAGE>


under any Options theretofore granted or awarded, unless the award itself 
otherwise expressly so provides.  No Options may be granted or awarded during 
any period of suspension or after termination of this Plan, and in no event may 
any Incentive Stock Option be granted under this Plan after the first to occur 
of the following events:

      (a)   The expiration of ten (10) years from the date the Plan is 
adopted by the Board; or

      (b)   The expiration of ten (10) years from the date the Plan is 
approved by the Company's shareholders under Section 8.4.

      8.3.   CHANGES IN COMMON STOCK OR ASSETS OF THE COMPANY, ACQUISITION OR 
LIQUIDATION OF THE COMPANY AND OTHER CORPORATE EVENTS.

      (a)   Subject to Section 8.3(d), (A) in the event that the Committee 
(or the Board in the case of Options granted to Independent Directors) 
determines that any dividend or other distribution (whether in the form of 
cash, Common Stock, other securities, or other property), recapitalization, 
reclassification, reorganization, merger, consolidation, split-up, spin-off, 
combination, repurchase, liquidation, dissolution, or sale, transfer, 
exchange or other disposition of all or substantially all of the assets of 
the Company (including, but not limited to, a Corporate Transaction), or 
exchange of Common Stock or other securities of the Company, issuance of 
warrants or other rights to purchase Common Stock or other securities of the 
Company, or other similar corporate transaction or event, in the Committee's 
sole discretion (or, in the case of Options granted to Independent Directors, 
the Board's sole discretion), affects the Common Stock such that an 
adjustment is determined by the Committee (or the Board in the case of 
Options granted to Independent Directors) to be appropriate in order to 
prevent dilution or enlargement of the benefits or potential benefits 
intended to be made available under the Plan or with respect to an Option, or 
(B) in the event of any stock split or reverse stock split, then the 
Committee (or the Board in the case of Options granted to Independent 
Directors) shall, in such manner as it may deem equitable, adjust any or all 
of

         (i)    the number and kind of shares of Common Stock (or other 
securities or property) with respect to which Options may be granted under 
the Plan, (including, but not limited to, adjustments of the limitations in 
Section 2.1 on the maximum number and kind of shares which may be issued and 
adjustments of the Award Limit),

         (ii)   the number and kind of shares of Common Stock (or other 
securities or property) subject to outstanding Options, and

         (iii)  the grant or exercise price with respect to any Option.

      (b)   Subject to Sections 8.3(b)(vi) and 8.3(d), in the event of any 
Corporate Transaction or other transaction or event described in Section 
8.3(a) or any 


                                    18
<PAGE>


unusual or nonrecurring transactions or events affecting the Company, any 
Affiliate of the Company, or the financial statements of the Company or any 
Affiliate, or of changes in applicable laws, regulations, or accounting 
principles, the Committee (or the Board in the case of Options granted to 
Independent Directors) in its discretion is hereby authorized to take any one 
(1) or more of the following actions whenever the Committee (or the Board in 
the case of Options granted to Independent Directors) determines that such 
action is appropriate in order to prevent dilution or enlargement of the 
benefits or potential benefits intended to be made available under the Plan 
or with respect to any option under this Plan, to facilitate such 
transactions or events or to give effect to such changes in laws, regulations 
or principles:

         (i)    In its sole and absolute discretion, and on such terms and 
conditions as it deems appropriate, the Committee (or the Board in the case 
of Options granted to Independent Directors) may provide, either by the terms 
of the agreement or by action taken prior to the occurrence of such 
transaction or event and either automatically or upon the Optionee's request, 
for either the purchase of any such Option for an amount of cash equal to the 
amount that could have been attained upon the exercise of such Option, or 
realization of the Optionee's rights had such Option been currently 
exercisable or payable or fully vested or the replacement of such Option with 
other rights or property selected by the Committee (or the Board in the case 
of Options granted to Independent Directors) in its sole discretion;

         (ii)   In its sole and absolute discretion, the Committee (or the 
Board in the case of Options granted to Independent Directors) may provide, 
either by the terms of such Option or by action taken prior to the occurrence 
of such transaction or event that it cannot be exercised after such event;

         (iii)  In its sole and absolute discretion, and on such terms and 
conditions as it deems appropriate, the Committee (or the Board in the case 
of Options granted to Independent Directors) may provide, either by the terms 
of such Option or by action taken prior to the occurrence of such transaction 
or event, that for a specified period of time prior to such transaction or 
event, such Option shall be exercisable as to all shares covered thereby, 
notwithstanding anything to the contrary in (i) Section 4.4 or (ii) the 
provisions of such Option;

         (iv)   In its sole and absolute discretion, and on such terms and 
conditions as it deems appropriate, the Committee (or the Board in the case 
of Options granted to Independent Directors) may provide, either by the terms 
of such Option or by action taken prior to the occurrence of such transaction 
or event, that upon such event, such Option be assumed by the successor or 
survivor corporation, or a parent or subsidiary thereof, or shall be 
substituted for by similar options covering the stock of the successor or 
survivor corporation, or a parent or subsidiary thereof, with appropriate 
adjustments as to the number and kind of shares and prices;


                                        19
<PAGE>


         (v)    In its sole and absolute discretion, and on such terms and 
conditions as it deems appropriate, the Committee (or the Board in the case 
of Options granted to Independent Directors) may make adjustments in the 
number and type of shares of Common Stock (or other securities or property) 
subject to outstanding Options and/or in the terms and conditions of 
(including the grant or exercise price), and the criteria included in, 
outstanding Options and Options which may be granted in the future; and

         (vi)   None of the foregoing discretionary actions taken under this 
Section 8.3(b) shall be permitted with respect to Options granted to 
Independent Directors to the extent that such discretion would be 
inconsistent with the applicable exemptive conditions of Rule 16b-3.  In the 
event of a Corporate Transaction, to the extent that the Board does not have 
the ability under Rule 16b-3 to take or to refrain from taking the 
discretionary actions set forth in Section 8.3(b)(iii) above, each Option 
granted to an Independent Director shall be exercisable as to all shares 
covered thereby during the five days immediately preceding the consummation 
of such Corporate Transaction and subject to such consummation, 
notwithstanding anything to the contrary in Section 4.4 or the vesting 
schedule of such Options.  In the event of a Corporate Transaction, to the 
extent that the Board does not have the ability under Rule 16b-3 to take or 
to refrain from taking the discretionary actions set forth in Section 
8.3(b)(ii) above, no Option granted to an Independent Director may be 
exercised following such Corporate Transaction unless such Option is, in 
connection with such Corporate Transaction, either assumed by the successor 
or survivor corporation (or parent or subsidiary thereof) or replaced with a 
comparable right with respect to shares of the capital stock of the successor 
or survivor corporation (or parent or subsidiary thereof).

      (c)   Subject to Section 8.3(d) and 8.8, the Committee (or the Board in 
the case of Options granted to Independent Directors) may, in its discretion, 
include such further provisions and limitations in any Option as it may deem 
equitable and in the best interests of the Company.

      (d)   With respect to Incentive Stock Options and Options intended to 
qualify as performance-based compensation under Section 162(m), no adjustment 
or action described in this Section 8.3 or in any other provision of the Plan 
shall be authorized to the extent that such adjustment or action would cause 
the Plan to violate Section 422(b)(1) of the Code or would cause such option 
to fail to so qualify under Section 162(m), as the case may be, or any 
successor provisions thereto.  Furthermore, no such adjustment or action 
shall be authorized to the extent such adjustment or action would result in 
short-swing profits liability under Section 16 or violate the exemptive 
conditions of Rule 16b-3 unless the Committee (or the Board in the case of 
Options granted to Independent Directors) determines that the Option is not 
to comply with such exemptive conditions.  The number of shares of Common 
Stock subject to any Option shall always be rounded to the next whole number.

      8.4.   APPROVAL OF PLAN BY SHAREHOLDERS.  This Plan will be submitted 
for the approval of the Company's shareholders within twelve months after the 
date of the 


                                        20
<PAGE>


Board's initial adoption of this Plan.  Options may be granted prior to such 
shareholder approval, provided that such Options shall not be exercisable 
prior to the time when this Plan is approved by the shareholders, and 
provided further that if such approval has not been obtained at the end of 
said twelve-month period, all Options previously granted under this Plan 
shall thereupon be canceled and become null and void.

      8.5.   TAX WITHHOLDING.  The Company shall be entitled to require 
payment in cash or deduction from other compensation payable to each Optionee 
of any sums required by federal, state or local tax law to be withheld with 
respect to the issuance, vesting or exercise of any Option.  The Committee 
(or the Board in the case of Options granted to Independent Directors) may in 
its discretion and in satisfaction of the foregoing requirement allow such 
Optionee to elect to have the Company withhold shares of Common Stock 
otherwise issuable under such Option (or allow the return of shares of Common 
Stock) having a Fair Market Value equal to the sums required to be withheld.

      8.6.   LOANS.  The Committee may, in its discretion, extend one (1) or 
more loans to key Employees in connection with the exercise or receipt of an 
Option granted under this Plan.  The terms and conditions of any such loan 
shall be set by the Committee.

      8.7.   FORFEITURE PROVISIONS.  Pursuant to its general authority to 
determine the terms and conditions applicable to awards under the Plan, the 
Committee (or the Board in the case of Options granted to Independent 
Directors) shall have the right (to the extent consistent with the applicable 
exemptive conditions of Rule 16b-3 and to the extent permitted under 
applicable state law) to provide, in the terms of Options made under the 
Plan, or to require the recipient to agree by separate written instrument, 
that (i) any proceeds, gains or other economic benefit actually or 
constructively received by the recipient upon any receipt or exercise of an 
Option, or upon the receipt or resale of any Common Stock underlying such 
Option, must be paid to the Company, and (ii) the Option shall terminate and 
any unexercised portion of such Option (whether or not vested) shall be 
forfeited, if (a) a Termination of Directorship, Termination of Employment or 
Termination of Consultancy occurs prior to a specified date, or within a 
specified time period following receipt or exercise of the Option, or (b) the 
recipient at any time, or during a specified time period, engages in any 
activity in competition with the Company, or which is inimical, contrary or 
harmful to the interests of the Company, as further defined by the Committee 
(or the Board, as applicable).

      8.8.   LIMITATIONS APPLICABLE TO SECTION 16 PERSONS AND 
PERFORMANCE-BASED COMPENSATION.  Notwithstanding any other provision of this 
Plan, this Plan, and any Option granted to any individual who is then subject 
to Section 16 of the Exchange Act, shall be subject to any additional 
limitations set forth in any applicable exemptive rule under Section 16 of 
the Exchange Act (including any amendment to Rule 16b-3 of the Exchange Act) 
that are requirements for the application of such exemptive rule.  To the 
extent permitted by applicable law, the Plan and Options granted or awarded 
hereunder 


                                        21
<PAGE>


shall be deemed amended to the extent necessary to conform to such applicable 
exemptive rule.  Furthermore, notwithstanding any other provision of this 
Plan, any Option intended to qualify as performance-based compensation as 
described in Section 162(m)(4)(C) of the Code shall be subject to any 
additional limitations set forth in Section 162(m) of the Code (including any 
amendment to Section 162(m) of the Code) or any regulations or rulings issued 
thereunder that are requirements for qualification as performance-based 
compensation as described in Section 162(m)(4)(C) of the Code, and this Plan 
shall be deemed amended to the extent necessary to conform to such 
requirements.

      8.9.   EFFECT OF PLAN UPON OPTIONS AND COMPENSATION PLANS.  The 
adoption of this Plan shall not affect any other compensation or incentive 
plans in effect for the Company or any Subsidiary.  Nothing in this Plan 
shall be construed to limit the right of the Company (i) to establish any 
other forms of incentives or compensation for Employees, directors or 
consultants of the Company or any Subsidiary or (ii) to grant or assume 
options or other rights otherwise than under this Plan in connection with any 
proper corporate purpose including but not by way of limitation, the grant or 
assumption of options in connection with the acquisition by purchase, lease, 
merger, consolidation or otherwise, of the business, stock or assets of any 
corporation, partnership, limited liability company, firm or association.

      8.10.   COMPLIANCE WITH LAWS.  This Plan, the granting and vesting of 
Options under this Plan and the issuance and delivery of shares of Common 
Stock and the payment of money under this Plan or under Options granted 
hereunder are subject to compliance with all applicable federal and state 
laws, rules and regulations (including but not limited to state and federal 
securities law and federal margin requirements) and to such approvals by any 
listing, regulatory or governmental authority as may, in the opinion of 
counsel for the Company, be necessary or advisable in connection therewith.  
Any securities delivered under this Plan shall be subject to such 
restrictions, and the person acquiring such securities shall, if requested by 
the Company, provide such assurances and representations to the Company as 
the Company may deem necessary or desirable to assure compliance with all 
applicable legal requirements.  To the extent permitted by applicable law, 
the Plan and Options granted or awarded hereunder shall be deemed amended to 
the extent necessary to conform to such laws, rules and regulations.

      8.11.   TITLES.  Titles are provided herein for convenience only and 
are not to serve as a basis for interpretation or construction of this Plan.

      8.12.   GOVERNING LAW.  This Plan and any agreements hereunder shall be 
administered, interpreted and enforced under the internal laws of the State 
of Delaware without regard to conflicts of laws thereof.

                                       * * *


                                         22
<PAGE>


      I hereby certify that the foregoing Plan was duly adopted by the Board 
of Directors of Eco Soil Systems, Inc. on April 29, 1998.

      Executed on this 12th day of August, 1998.



                                       By:  /s/  L. Jean Dunn, Jr.
                                          ------------------------------
                                            L. Jean Dunn, Jr.
                                            Secretary



                                          24