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                FIRST AMENDMENT TO CREDIT AGREEMENT AND WAIVER

This First Amendment and Waiver ("Amendment") amends that certain Credit 
Agreement ("Agreement"), dated December 2, 1998, by and between Imperial Bank 
("Bank") and Eco Soil Systems, Inc., a Nebraska Corporation, Aspen Consulting 
Companies, Inc., a Colorado Corporation, Turf Specialty, Inc., a Delaware 
Corporation, Eco Turf Products, Inc., a Delaware Corporation, Mitigation 
Services, Inc., a Delaware Corporation, Agricultural Supply, Inc., a Delaware 
Corporation, Benham Chemical Corporation, a Michigan Corporation, Turf 
Acquisition Sub, Inc., a Delaware Corporation, and Yuma Acquisition Sub, 
Inc., a Delaware Corporation (collectively, "Borrower") and waives certain 
covenant breaches in the Agreement as follows:

I.    Borrower is in default of the following sections of the Agreement:

      4.05(a) MONTHLY FINANCIAL STATEMENT. As soon as available, and in any 
      event within thirty (30) days after the close of each month, a 
      consolidated balance sheet, profit and loss statement and reconcilation 
      of Borrower's capital balance accounts as of the close of such period 
      and covering operations for the portion of Borrower's fiscal year 
      ending on the last day of such period, all in reasonable detail and 
      reasonably acceptable to Bank, in accordance with generally accepted 
      accounting principles on a basis consistently maintained by Borrower 
      and certified by an appropriate officer of Borrower.

      Borrower is currently past due for the January 31, 1999 monthly 
      financial statement.

      4.06  MODIFIED QUICK RATIO.  Maintain at all times a consolidated 
      minimum ratio of total accounts receivable divided by total Trading 
      Liabilities (meaning the total of Revolving Loans, accounts payable and 
      accrued liabilities) of .85 to 1.00.

      The modified quick ratio as of December 31, 1998 was approximately 
      .63:1.00 which is below the minimum.

      4.07 TRADING CAPITAL. Maintain at all times consolidated Trading 
      Capital (meaning total accounts receivable and inventory minus total 
      Trading Liabilities as defined in section 4.06) of not less than 
      fifteen million dollars ($15,000,000).

      The trading capital as of December 31, 1998 was approximately 
      $12,503,000 which is below the minimum.

      4.08 EFFECTIVE TANGIBLE NET WORTH.  Maintain at all times a 
      consolidated Effective Tangible Net Worth (defined as (a) stockholder's 
      equity (including without limitation preferred stock) less any value 
      for goodwill, trademarks, patents, copyrights, leaseholds, organization 
      expense and other similar intangible items, and any amounts due from 
      stockholders, officers and affiliates plus (b) subordinated debt 
      including, without limitation, the $15,000,000.00 offering of senior 
      subordinated notes with detachable warrants offered pursuant to the 
      Note and Warrant Purchase Agreement and the Common Stock Purchase 
      Warrant, each dated as of August 25, 1998) of not less than thirty-six 
      million dollars ($36,000,000).

      The Effective Tangible Net Worth as of December 31, 1998 was 
      approximately $29,752,000 which is below the minimum.

      4.09 TOTAL LIABILITIES TO EFFECTIVE TANGIBLE NET WORTH. Maintain at all 
      times a consolidated ratio of total liabilities to Effective Tangible 
      Net Worth (as defined in section 4.08) of not greater than .75 to 1.00.

      The ratio of total liabilities to Effective Tangible Net Worth as of 
      December 31, 1998 was approximately .79:1.00 which is above the maximum.

      4.10 PROFITABILITY. Maintain on a consolidated basis, profitable 
      operations (meaning a net profit after taxes) of at least one dollar 
      ($1) on an annual (calendar year) basis.

      Profitable operations as of December 31, 1998 was a negative value 
      which is below the minimum.

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ECO SOIL SYSTEMS INC.
AMENDMENT NO. 1
PAGE 2


      5.06 LOSSES.  Incur losses in the first quarter of fiscal 1999 (ended 
      March 31) of greater than two million five hundred thousand dollars 
      ($2,500,000) or incur quarterly losses in excess of one dollar ($1) in 
      any two consecutive calendar quarters.

      Quarterly losses as of 4th quarter ending December 31, 1998 were 
      approximately $12,170,000 and 1st quarter losses ending March 31, 1999 
      are anticipated to be approximately $2,675,000 which together are a 
      violation of this covenant.

2.    Bank hereby waives the aforementioned covenant defaults for the periods 
ending December 31, 1998 and March 31, 1999 only. The waiver contained herein 
is specific as to contents and time as shall not be construed as waiving any 
other past, presently existing or future noncompliance with any covenant of 
the Agreement and in no way affects any rights and remedies that Bank may 
have with respect to any other noncompliance with any other covenant of the 
Agreement.

3.    Section 4.05(a) of the Agreement is hereby amended to read in its 
      entirety as follows:

      "MONTHLY FINANCIAL STATEMENT.  As soon as available, and in any event 
      within thirty (30) days after the close of each month, a consolidated 
      balance sheet, profit and loss statement and reconcilation of 
      Borrower's capital balance accounts as of the close of such period and 
      covering operations for the portion of Borrower's fiscal year ending on 
      the last day of such period, all in reasonable detail and reasonably 
      acceptable to Bank, in accordance with generally accepted accounting 
      principles on a basis consistently maintained by Borrower and certified 
      by an appropriate officer of Borrower."

4.    Section 4.06 of the Agreement is hereby amended to read in its 
      entirety as follows:

      "MODIFIED QUICK RATIO.  Maintain at all times a consolidated minimum 
      ratio of total accounts receivable divided by total Trading Liabilities 
      (meaning the total of Revolving Loans, accounts payable and accrued 
      liabilities) of .55 to 1.00."

5.    Section 4.07 of the Agreement is hereby amended to read in its entirety 
      as follows:

      "WORKING CAPITAL. Maintain at all times consolidated Working Capital of 
      not less than eleven million five hundred thousand dollars 
      ($11,500,000)."

6.    Section 4.08 of the Agreement is hereby amended to read in its entirety 
      as follows:

      "EFFECTIVE TANGIBLE NET WORTH.  Maintain at all times a consolidated 
      Effective Tangible Net Worth (defined as (a) stockholder's equity 
      (including without limitation preferred stock) less any value for 
      goodwill, trademarks, patents, copyrights, leaseholds, organization 
      expense and other similar intangible items, and any amounts due from 
      stockholders, officers and affiliates plus (b) subordinated debt 
      including, without limitation, the $15,000,000.00 offering of senior 
      subordinated notes with detachable warrants offered pursuant to the 
      Note and Warrant Purchase Agreement and the Common Stock Purchase 
      Warrant, each dated as of August 25, 1998) of not less than 
      twenty-seven million two hundred fifty thousand dollars ($27,250,000)."

7.    Section 4.09 of the Agreement is hereby amended to read in its entirety 
      as follows:

      "TOTAL LIABILITIES TO EFFECTIVE TANGIBLE NET WORTH. Maintain at all 
      times a consolidated ratio of total liabilities to Effective Tangible 
      Net Worth (as defined in section 4.08) of not greater than 1.25 to 1.00"

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ECO SOIL SYSTEMS INC.
AMENDMENT NO. 1
PAGE 3


8.    Section 4.10 of the Agreement is hereby amended to read in its entirety 
      as follows:

      "Maintain, at all times, from June 30, 1999, through December 31, 1999, 
      on a consolidated basis, year to date profitability of at least one 
      dollar ($1.00)."

9.    A new Section 5.07 is hereby added to the agreement to read in its 
      entirety as follows:

      "PREPAYMENT ON DEBT.  Make any principal prepayments on any of 
      Borrower's obligations, including but not limited to the $15,000,000.00 
      offering of senior subordinated notes with detachable warrants offered 
      pursuant to the Note and Warrant Purchase Agreement and the Common 
      Stock Purchase Warrant, each dated as of August 25, 1998."

10.   A new Section 6.11 is hereby added to the Agreement to read in its 
      entirety as follows:

      "LOAN RESTRUCTURE.  Failure of Borrower to complete, by April 16, 1999, 
      documentation to replace the Revolving Line of Credit with a 
      formula-based accounts receivable inventory line of credit with a 75% 
      advance rate on eligible accounts receivable and a 35% advance rate on 
      eligible inventory, with advances thereunder bearing interest at the one 
      percent (1.00%) in excess of the Prime Rate and with Borrower required 
      to submit a monthly borrowing base certificate along with accounts 
      receivable and accounts payable agings and an inventory certificate in 
      form acceptable to Bank. This restructuring shall include establishment 
      of a lock box service with Bank and appropriate notices to Borrower's 
      account debtors regarding lock box payments."

11.   Except as provided above, the Agreement remains unchanged and the       
parties hereby confirm that the Agreement as herein amended is in full       
force and effect.

12.   This Amendment is effective as of March 31, 1999, and upon (i) 
Borrower's payment to Bank of a waiver fee in the amount of $25,000 and (ii) 
Bank's receipt of a fully executed waiver, satisfactory to Bank of any Event 
of Default or Potential Event of Default (all as defined therein) under 
Borrower's 12.00% Senior Subordinated Note due 2003, and the parties hereby 
confirm that the Agreement as amended is in full force and effect.


ECO SOIL SYSTEMS, INC.
"Borrower"



By:  /s/ William B. Adams
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Title:  CEO
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IMPERIAL BANK
"Bank"


By:  /s/ Peter M. Drees
    ----------------------------

Title: Assistant Vice President 
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