EMCON
10-Q, 1998-05-12
ENGINEERING SERVICES
Previous: FCC NATIONAL BANK, 8-K, 1998-05-12
Next: MEDICAL INCOME PROPERTIES 2B LTD PARTNERSHIP, 10-Q, 1998-05-12







                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                    FORM 10-Q

(Mark One)

[ X ]    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                  For the quarterly period ended March 31, 1998

                                       OR

[    ]   TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                         Commission file number 0-16225

                                      EMCON

             (Exact name of Registrant as specified in its charter)


          California                                         94-1738964
 ----------------------------------                    ----------------------
(State or other jurisdiction of                          (I.R.S.Employer
incorporation or organization)                           Identification No.)

400 South El Camino Real, Suite 1200
San Mateo, California                                          94402
- ----------------------------------------------              ------------
(Address of  principal executive offices)                    (Zip Code)


       Registrant's telephone number, including area code: (650) 375-1522

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the  preceding 12 months (or for such  shorter  period that the  registrant  was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements for the past 90 days. Yes [ X ] No [ ]

8,715,464 shares of Common Stock Issued and Outstanding as of May 8, 1998.

                                       1
<PAGE>


                                      EMCON
                                      INDEX
                               REPORT ON FORM 10-Q
                      FOR THE QUARTER ENDED MARCH 31, 1998




                                                                          Page
                                                                         Number

FACING SHEET.........................................................         1

TABLE OF CONTENTS....................................................         2

PART I.   FINANCIAL INFORMATION

          Item 1. Financial Statements

                  Consolidated Balance Sheets -
                  March 31, 1998 and December 31, 1997...............         3

                  Consolidated Statements of Income -
                  Three months ended March 31, 1998 and 1997.........         4

                  Consolidated Statements of Cash Flows -
                  Three months ended March 31, 1998 and 1997.........         5

                  Notes to Consolidated Financial Statements.........         6

          Item 2. Management's Discussion and Analysis of
                  Financial Condition and Results of Operations......        11

PART II.   OTHER INFORMATION.........................................        13

Signatures...........................................................        14

Index to Exhibits....................................................        15

                                       2

<PAGE>
<TABLE>
<CAPTION>


   EMCON
   CONSOLIDATED BALANCE SHEETS
 ------------------------------------------------------------------------------------- -------------- ----------------
                                                                                         March 31,     December 31,
                                                                                           1998            1997
 (In thousands, except share amounts)                                                   (Unaudited)      (Audited)
 ------------------------------------------------------------------------------------- -------------- ----------------
<S>                                                                                      <C>           <C>
 
 ASSETS
 Current Assets:
 Cash and cash equivalents                                                               $  7,356      $  6,106
 Accounts Receivable:
     Billed accounts receivable, net of allowance for doubtful accounts
       of $689 and $634 at March 31, 1998 and December 31, 1997 respectively               24,808        31,413
     Unbilled accounts receivable, net of allowance for doubtful accounts
       of $283 and $295 at March 31, 1998 and December 31, 1997, respectively               6,659         5,310
 Costs and estimated earnings in excess of billings on
     uncompleted contracts                                                                  2,201           678
 Prepaid expenses and other current assets                                                  3,149         3,401
 Inventory                                                                                  2,703         2,238
 Deferred taxes, current portion                                                            4,235         4,235
                                                                                          -------       -------
     Total Current Assets                                                                  51,111        53,381

 Net property and equipment, at cost                                                       15,521        16,182
 Notes receivable                                                                           2,426         2,811
 Cash surrender value of insurance policies                                                 2,366         2,346
 Other assets                                                                               2,783         2,597
 Deferred tax assets                                                                        1,028         1,028
 Goodwill, net of amortization                                                             13,778        13,916
 Other intangible assets, net of amortization                                                 841           814
                                                                                         --------     ---------
     Total Assets                                                                         $89,854       $93,075
                                                                                          =======       =======
 LIABILITIES AND SHAREHOLDERS' EQUITY
 Current Liabilities:
 Accounts payable                                                                        $  5,218      $  8,391
 Accrued payroll and related benefits                                                       4,662         4,356
 Other accrued liabilities                                                                  3,266         2,969
 Billings in excess of costs and estimated earnings
     on uncompleted contracts                                                               2,785         2,732
 Long-term obligations due within one year                                                  2,269         2,350
                                                                                         --------      --------
     Total Current Liabilities                                                             18,200        20,798

 Long-term debt                                                                            10,816        11,441
  Other noncurrent obligations                                                              2,714         2,736
 Commitments and contingencies                                                                 --            --
 Shareholders' Equity:
 Preferred stock, no par value, 5,000,000 shares authorized;
     no shares issued or outstanding                                                           --            --
 Common stock, no par value, 15,000,000 shares authorized;
     8,577,262 and 8,571,764 shares issued and outstanding at
     March 31, 1998 and December 31, 1997, respectively                                    42,193        42,184
 Retained earnings                                                                         15,931        15,916
                                                                                           ------       -------
     Total Shareholders' Equity                                                            58,124        58,100
                                                                                           ------       -------
     Total Liabilities and Shareholders' Equity                                           $89,854       $93,075
                                                                                          =======       =======
See accompanying notes.

</TABLE>
                                       3
<PAGE>
<TABLE>
<CAPTION>

EMCON
CONSOLIDATED STATEMENTS OF INCOME
- --------------------------------------------------------------------------------- ---------------------------------
                                                                                         Three months ended
                                                                                             March 31,
                                                                                            (Unaudited)
                                                                                  ---------------------------------
(In thousands, except per share amounts)                                                1998             1997
- --------------------------------------------------------------------------------- ----------------- ---------------
<S>                                                                                    <C>               <C>
Gross revenue                                                                          $28,779           $31,363
Outside services at cost                                                                 2,957             3,782
                                                                                     ---------         ---------

         Net revenue                                                                    25,822            27,581

Costs and expenses:
     Direct expenses                                                                    13,822            12,606
     Indirect expenses                                                                  11,857            14,226
     Restructuring/other charges                                                            --               (75)
     Loss on disposition of laboratory                                                      --               333
     Gain on sale of assets                                                                 --              (826)
                                                                                    ----------          ---------

         Income from operations                                                            143             1,317

Interest income                                                                           (168)              (94)
Interest expense                                                                           293               331
Equity in income of affiliates                                                             (15)              (18)
Minority interest (income) expense                                                         (22)               35
                                                                                    -----------         --------

Income before provision for income taxes                                                    55             1,063
Provision for income taxes                                                                  35               372
                                                                                     ---------         ---------

Net income                                                                          $       20        $      691
                                                                                    ==========        ==========

Basic earnings per share                                                            $     0.00       $      0.08
                                                                                    ==========       ===========

Diluted earnings per share                                                          $     0.00       $      0.08
                                                                                    ==========       ===========

Shares used in computing basic earnings per share                                        8,573             8,535
                                                                                     =========        ==========

Shares used in computing diluted earnings per share                                      8,827             8,540
                                                                                     =========        ==========

</TABLE>
                                       4
<PAGE>

<TABLE>
<CAPTION>

EMCON
CONSOLIDATED STATEMENTS OF CASH FLOWS

- -------------------------------------------------------------------------- -------------------------------
                                                                                 Three months ended
                                                                                     March 31,
                                                                                    (Unaudited)
                                                                           -------------------------------
Increase (decrease) in cash and cash equivalents (in thousands)                 1998            1997
- -------------------------------------------------------------------------- ---------------- --------------
<S>                                                                           <C>               <C>
Cash flow from operating activities:
Net income                                                                    $     20          $   691
Adjustments to reconcile net income to net cash provided by (used for)
operating activities:
   Depreciation                                                                    967              893
   Amortization                                                                    153              151
   Bad debt expense                                                                 73              501
   Gain on sale/disposal of property and equipment                                (257)            (142)
   Loss on disposition of laboratory                                                --              333
   Gain on disposition of assets                                                    --             (826)
   Increase in salary continuation plan                                             40               17
   Changes in operating assets and liabilities:
       Accounts receivable                                                       5,183           (2,256)
       Costs and estimated earnings in excess of billings on uncompleted        (1,523)            (346)
       contracts
       Inventory                                                                  (465)            (489)
       Prepaid expenses and other assets                                           252              385
       Notes receivable                                                            385              116
       Cash surrender value, insurance policies                                    (20)            (185)
       Other assets                                                               (268)             (78)
       Accounts payable                                                         (3,173)            (416)
       Accrued payroll and related benefits                                        306           (1,247)
       Billings in excess of costs and estimated earnings on uncompleted            53            1,189
       projects
       Other accrued liabilities                                                   275              604
- -------------------------------------------------------------------------- ---------------- --------------

          Net cash provided by (used for) operating activities                   2,001           (1,105)
- -------------------------------------------------------------------------- ---------------- --------------
Cash flow from investing activities:
   Additions to property and equipment                                            (395)          (1,157)
   Net cash on disposition of laboratory                                            --            3,794
   Net cash from dispositions of assets                                             --              840
   Proceeds from sale of property and equipment                                    346              512
- -------------------------------------------------------------------------- ---------------- --------------

          Net cash (used for) provided by investing activities                     (49)           3,989
- -------------------------------------------------------------------------- ---------------- --------------
Cash flow from financing activities:
   Proceeds of new debt obligation                                                  --              250
   Payments of current and long term portion of debt                              (706)            (619)
   Issuance of common stock for cash, net of cancellations                           9               76
   Dividend payments                                                                (5)             (21)
- -------------------------------------------------------------------------- ---------------- --------------

          Net cash used for financing activities                                  (702)            (314)
- -------------------------------------------------------------------------- ---------------- --------------
Increase in cash and cash equivalents                                            1,250            2,570
Cash and cash equivalents, beginning of year                                     6,106            5,331
- -------------------------------------------------------------------------- ---------------- --------------
Cash and cash equivalents, end of year                                          $7,356           $7,901
- -------------------------------------------------------------------------- ---------------- --------------
See accompanying notes.

</TABLE>
                                       5
<PAGE>


                                      EMCON

                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
                                   (Unaudited)

1.   Basis of Presentation

     The accompanying  consolidated financial statements include the accounts of
     the Company and its  wholly-owned  subsidiaries  after  elimination  of all
     significant intercompany accounts and transactions.

     While the financial information is unaudited, the statements in this report
     reflect all adjustments, which are normal and recurring, that are necessary
     for a fair  presentation  of the  results  of  operations  for the  interim
     periods covered and of the financial  condition of the Company at the dates
     of the consolidated  balance sheets.  The operating results for the interim
     periods  presented are not  necessarily  indicative of performance  for the
     entire year.

     These  consolidated  financial  statements  and  notes  should  be  read in
     conjunction with the Company's  consolidated  financial  statements for the
     fiscal year ended December 31, 1997.

2.   Restructuring Charges

     In the fourth  quarter of 1996,  senior  management  reviewed the Company's
     operational  and  administrative  functions  for  the  purpose  of  further
     improving the Company's competitiveness and overall profitability. Based on
     this  review,  the  Company's  Board  of  Directors  approved  a  strategic
     restructuring  plan to  reposition  the  Company to fully  exploit its core
     strengths in engineering, design, construction, operations and maintenance.
     The  plan  included  closure  or  downsizing  of  underperforming  offices,
     write-off  of  employment   contracts   for  former   employees  no  longer
     participating in the Company's affairs and employee  severance.  During the
     quarter ended March 31, 1998,  $18,000 relating to the  restructuring  were
     incurred and charged  against the established  reserve.  At March 31, 1998,
     $346,000 of accrued  restructuring  costs have been  incurred  and $300,000
     remains in other accrued liabilities.

3.   Acquisition

     Effective May 1, 1997,  Organic Waste Technology,  Inc.  ("OWT"),  a wholly
     owned subsidiary of EMCON,  acquired all of the equity interest in National
     Earth Products, Inc. ("NEP"), a Lancaster,  Pennsylvania-based company with
     significant  expertise in landfill  civil  construction  and related  soils
     processing.  NEP was  acquired  for  $933,000 in cash and $800,000 in notes
     payable.  The  transaction  was accounted  for as a purchase.  Specifically
     identifiable  intangible  assets and goodwill of  approximately  $1,476,000
     resulting  from this  acquisition  are  included in goodwill  and are being
     amortized   over   twenty-five   years  using  the  straight  line  method.
     Accumulated  amortization as of March 31, 1998, was approximately  $54,000.
     Additional consideration may be paid for the purchase of NEP subject to the
     achievement  of  certain  earnout  goals  over  the next  two  years.  This
     acquisition  would  not have had a  material  effect  on net  revenue,  net
     income, or income per share, had it been effective at January 1, 1997.

                                       6

<PAGE>


4.   Credit Agreement

     In  conjunction  with the  acquisition  of OWT, the Company  entered into a
     $20,000,000  secured credit  agreement with its existing  commercial  bank,
     replacing its previous $10,000,000  unsecured line of credit. Under the new
     agreement,  the  Company  borrowed  $10,000,000  on a long term  basis with
     interest  at a  variable  rate,  generally  not to exceed  the prime  rate.
     Principal is to be amortized  over seven years,  but with any unpaid amount
     finally due and payable on June 30, 2001.  In April,  1997,  following  the
     infusion of cash upon the first  quarter sale of the  Company's  laboratory
     operations, the Company prepaid, on an accelerated basis, $3,000,000 of the
     then  outstanding  principal  balance  of  the  term  loan.  The  remaining
     $10,000,000  under the credit  agreement  is  available on a line of credit
     basis for working  capital  purposes  (with up to $5,000,000 of this amount
     available for non-working  capital purposes).  The line of credit component
     of the credit agreement expires on May 31, 1998.

5.   Litigation

     As a professional services firm engaged in  environmental-related  matters,
     the  Company   encounters   potential   liability,   including  claims  for
     significant  environmental  damage in the normal  course of  business.  The
     Company is party to lawsuits and is aware of potential  exposure related to
     certain  claims,  but in the opinion of management  the resolution of these
     matters  will  not  have  a  material   adverse  effect  on  the  Company's
     consolidated financial position, results of operations or cash flows.
<TABLE>
<CAPTION>

6.  Earnings Per Share
    -------------------------------------------------------------------------------------------------------------
                                                                                               Three months ended
                                                                                                   March 31,
                                                                                              -------------------
    (In thousands, except for earnings per share)                                              1998          1997
    -------------------------------------------------------------------------------------------------------------
    <S>                                                                                       <C>         <C>
    Numerator:
     Net income                                                                               $   20      $   691
                                                                                              ------      -------
     Numerator for basic earnings per share -
         income available to common stockholders                                                  20          691
     Effect of dilutive securities:
         8% convertible debentures                                                               N/A(1)       N/A(1)
                                                                                              ------      -------
     Numerator for diluted earnings per share -
         income available to common stockholders
         after assumed conversions                                                                20          691
                                                                                              ======      =======
    Denominator:
    Denominator for basic earnings per share -
         weighted-average shares                                                               8,573        8,535
    Effect of dilutive securities:
         Employee stock options                                                                  254            5
         8% convertible debentures                                                               N/A(1)       N/A(1)
    Dilutive potential common shares
    Denominator for diluted earnings per share -
         adjusted weighted average shares and assumed                                          8,827        8,540
                                                                                              ======       ======
         conversions
    Basic earnings per share                                                                  $ 0.00       $ 0.08
                                                                                              ======       ======
    Diluted earnings per share                                                                $ 0.00       $ 0.08
                                                                                              ======       ======
    -------------------------------------------------------------------------------------------------------------
     (1)Excluded  from the  above  reconciliations  were  approximately  269,000
     shares of  common  stock  that may be issued at $6.50 per share to  convert
     $1,747,000 of indebtedness to certain senior management of OWT because they
     were  antidilutive  at March 31, 1998.  Conversion  of debt,  if it occurs,
     would be within ninety days after November 30, 2001. Also excluded from the
     above  reconciliations  were  approximately  123,000 shares of common stock
     that may be issued at $6.50 per share to convert  $800,000 of  indebtedness
     to certain senior management of NEP because they were antidilutive at March
     31, 1998.  Conversion of debt,  if it occurs,  would be 50% at May 1, 2000,
     and 50% at May 1, 2002.
</TABLE>

                                       7

<PAGE>


7.   Other

     In 1994, the Company converted to a fifty-two/fifty-three  week fiscal year
     which will result in a fifty-two  week year in 1998. The Company's year end
     falls on the  Friday  closest  to the last day of the  calendar  year.  The
     Company  also  follows  a   five-four-four   week  quarterly   cycle.   For
     convenience,  the  accompanying  financial  statements  have been  shown as
     ending on the last day of the calendar period.

8.   Adoption of Statement 131

     Effective  January 1, 1998,  the Company  adopted the Financial  Accounting
     Standards  Board's  Statement of Financial  Accounting  standards  No. 131,
     Disclosure  about  Segments  of  an  Enterprise  and  Related  Information,
     ("Statement  131").  Statement 131 superseded FASB Statement 14,  Financial
     Reporting for Segments of a Business Enterprise.  Statement 131 establishes
     standards for the way that public business  enterprises  report information
     about operating  segments in annual financial  statements and requires that
     those enterprises  report selected  information about operating segments in
     interim  financial  reports.  The adoption of Statement  131 did not affect
     results of operations or financial position,  but did affect the disclosure
     of segment information. See note 9.

9.   Segment Reporting

     Description  of the types of services  from which each  reportable  segment
     derives its revenues.

     EMCON   provides   comprehensive    environmental   engineering,    design,
     construction,   operations  and  maintenance,   and  equipment  fabrication
     services  to a variety of public and  private  industrial  and solid  waste
     clients.  The  Company  is  comprised  of two  reportable  segments  -- the
     Operations and Construction  Division (EOC) and the  Professional  Services
     Division (PSD) -- and services three key service lines:  Solid Waste,  Site
     Restoration and Facility Services.

     In the first  quarter of 1997,  the  Company  had,  in  addition to the two
     reportable  segments listed above, a third reportable segment which was its
     laboratory  operations known as Columbia Analytical  Services,  Inc. (CAS).
     During the first quarter of 1997, the Company completed the sale of CAS.

     Measurement of segment profit or loss and segment assets.

     The Company evaluates performance of its reportable segments,  EOC and PSD,
     based on  operating  income or loss  before  and after  corporate  overhead
     allocations, but before interest income, interest expense, equity in income
     of affliates  and  minority  interest  income  (loss).  Corporate  overhead
     expenses are  substantially  allocated to the reporting  segments  based on
     revenue and/or  headcount when an item cannot be specifically  identifiable
     to a reporting segment.  The accounting policies of the reportable segments
     are the same as those  described in the summary of  significant  accounting
     policies as disclosed in EMCON's Form 10K as of December 31, 1997.

     Intersegment  sales consist primarily of labor and are marked up to provide
     the  supplying  reportable  segment  a measure  of  profit.  The  receiving
     reportable  segment records the transfer as an "Outside Service" and may or
     may not further mark up the labor cost prior to passing

                                       8
<PAGE>


     the cost through to its customer.  If the cost is not passed through to the
     customer,  the receiving  reportable  segment records the transaction as an
     indirect cost. All intersegment accounts are eliminated in consolidation.

     Factors management used to identify the enterprise's reportable segments.

     EMCON's  reportable  segments  are  divisional  units that offer  different
     services.  The  reportable  segments are each managed  separately.  The PSD
     reportable  segment  concentrates on professional  engineering,  design and
     consulting  services  in  solid  waste,  site  restoration  and  facilities
     services.  The PSD reportable segment has regional  operations  situated in
     the  North,  South,  Northwest  and  Southwest,  each  overseen  by an Area
     Operations  Manager.  These  regional  operations  have the same  operating
     parameters (services offered and required operating margins), may serve the
     same national  customers and often share personnel.  For reportable segment
     reporting,  these regional  operations are  aggregated.  The EOC reportable
     segment concentrates on construction,  equipment fabrication and operations
     and maintenance services, primarily to our solid waste clients.

     In  1997,  there  was  a  third  reportable  segment,  Columbia  Analytical
     Services,  Inc.  (CAS), a laboratory  division that was  subsequently  sold
     during the first quarter of 1997.
<TABLE>
<CAPTION>

     Segment Information
       ----------------------------------------------------------------------------------------------------------------
       (Three months ended March 31, 1998)                      PSD        EOC           CAS        Other         Total
       ----------------------------------------------------------------------------------------------------------------
       <S>                                                  <C>        <C>               <C>       <C>          <C>
       Gross revenues from:
            External customers                              $18,047    $10,732           N/A       $   --       $28,779
            Intersegment revenues                               197        524           N/A           --           721
       Outside services from:
            External subcontractors                           2,872         85           N/A           --         2,957
            Intersegment services                               572        151           N/A           --           723
       Net revenues                                          14,800     11,020           N/A            2        25,822
       Depreciation expense                                     553        343           N/A           71           967
       Amortization expense                                      --         15           N/A          138           153
       Segment operating profit (loss) before allocations       721        881           N/A           --         1,602
       Segment operating profit (loss) after allocations       (230)       382           N/A           (9)          143
       Segment assets(1)
            Accounts receivable, net                        $21,215    $10,252           N/A       $   --       $31,467
       ----------------------------------------------------------------------------------------------------------------
       (Three months ended March 31, 1997)
       ----------------------------------------------------------------------------------------------------------------
       Gross revenues from:
            External customers                              $20,916     $5,988       $ 4,453      $     6       $31,363
            Intersegment revenues                               331        580           734           --         1,645
       Outside services from:
            External subcontractors                           3,507         --           275           --         3,782
            Intersegment services                             1,479        132             8           --         1,619
       Net revenues                                          16,261      6,436         4,904          (20)       27,581
       Depreciation expense                                     424        292           462          177         1,355
       Amortization expense                                      --         --            --          151           151
       Restructuring/other charges                               --         --            --          (75)          (75)
       Loss on disposition of laboratory                         --         --            --          333           333
       Gain on sale of assets                                    --        826            --           --           826
       Segment operating profit (loss) before allocations     1,520      1,076           108           --         2,704
       Segment operating profit (loss) after allocations        880        703           (59)        (207)        1,317
       Segment assets(1)
            Accounts receivable, net                        $26,807     $7,808       $    --      $    --       $34,615
       ----------------------------------------------------------------------------------------------------------------
       (1)The Company  reviews its  consolidated  balance sheet and reviews only
       accounts receivable on a segment basis.
</TABLE>
                                       9

<PAGE>

<TABLE>
<CAPTION>


       ----------------------------------------------------------------------------------------------------------------

       Three months ended March 31,                                                                  1998          1997
       ----------------------------------------------------------------------------------------------------------------
       <S>                                                                                        <C>           <C>    
       Revenues
       Total external revenues for reportable segments                                            $28,779       $31,357
       Intersegment revenues for reportable segments                                                  721         1,645
       Other revenues                                                                                  --             6
       Elimination of intersegment revenues                                                          (721)       (1,645)
                                                                                                  -------       -------
            Total gross consolidated revenues                                                      28,779        31,363
       Less outside services                                                                        2,957         3,782
                                                                                                  -------       -------
             Total net revenue                                                                    $25,822       $27,581
       ----------------------------------------------------------------------------------------------------------------
       Profit or Loss
       Total operating profit for reportable segments before allocations                          $ 1,602       $ 2,704
       Overhead allocations expense                                                                (1,450)       (1,180)
       Unallocated overhead                                                                            (9)         (207)
                                                                                                  -------       -------
             Total operating profit after allocations                                                 143         1,317
       
       Interest income                                                                                168            94
       Interest expense                                                                              (293)         (331)
       Equity earnings                                                                                 15            18
       Minority interest                                                                               22           (35)
                                                                                                 --------       -------
            Income before income taxes                                                            $    55       $ 1,063
       ----------------------------------------------------------------------------------------------------------------


       March 31,                                                                                     1998          1997
       ----------------------------------------------------------------------------------------------------------------
       Assets
       Accounts receivable for reportable segments                                                $31,467       $34,615
       Other current assets                                                                        19,644        14,116
       Net property and equipment at cost                                                          15,521        14,552
       Goodwill, net of amortization                                                               13,778        13,501
       Other assets                                                                                 9,444        12,629
                                                                                                  -------       -------
            Total consolidated assets                                                             $89,854       $89,413
       ----------------------------------------------------------------------------------------------------------------
      

</TABLE>
                                       10

<PAGE>



                                      EMCON

ITEM 2.       Management's Discussion and Analysis of Financial Condition and 
              Results Of Operations.

RESULTS OF OPERATIONS

Net Revenue.  Net revenue for the first quarter of 1998 totaled  $25,822,000,  a
6.4% decrease from  $27,581,000  for the first quarter of 1997.  The decrease in
net revenue was, in part, attributable to the divestiture of Columbia Analytical
Services,  Inc. (CAS), a reportable  segment, at the end of the first quarter of
1997 (CAS  contributed  $4,904,000 to net revenue in the first quarter of 1997).
Excluding  net  revenue  contributed  by CAS in the first  quarter of 1997,  net
revenue  increased  13.9% in the first quarter of 1998 from  $22,677,000  in the
same period in 1997. The increase in net revenue  (excluding  CAS) was primarily
due to a 71.2% increase in net revenue from EMCON's  Operations and Construction
(EOC)  reportable  segment as the demand for its  services  continues to expand.
This was offset by a 9.0% decrease in net revenue from the Professional Services
reportable segment (PSD) due to unanticipated  project delays,  unusually severe
weather  conditions and the anticipated impact from the contraction of the PSD's
operations throughout the course of 1997.

Direct  Expenses.  Direct expenses  include  compensation for billable hours for
technical and professional staff and other project related expenses,  as well as
direct labor and materials  for in-house  testing and  construction  activities.
Direct  expenses  for the first  quarter  of 1998  totaled  $13,822,000,  a 9.6%
increase from $12,606,000 during the first quarter of 1997. Excluding the impact
of CAS (which  incurred  direct  expenses of  $2,267,000 in the first quarter of
1997) direct expenses  increased 33.7% from  $10,339,000 in the first quarter of
1997. As a percentage of net revenue, direct expenses as reported increased from
45.7% in the first  quarter of 1997 (45.6% if the impact of CAS is  excluded) to
53.5% in the first  quarter  of 1998.  The  increase  was due in large part to a
shift in business mix resulting from the  divestiture of CAS, the contraction of
the PSD  reportable  segment and the continued  expansion of the EOC  reportable
segment.

Indirect   Expenses.   Indirect   expenses   include  salary   compensation  for
non-billable  hours for  professional,  technical and  administrative  staff and
general  administrative  expenses such as rent,  bonuses,  benefits,  insurance,
legal, depreciation and amortization. Indirect expenses for the first quarter of
1998 totaled $11,857,000, a 16.7% decrease from indirect expenses of $14,226,000
during the first quarter of 1997.  Excluding  the impact of CAS (which  incurred
indirect  expenses of $2,529,000 in the first quarter of 1997) indirect expenses
during the quarter  increased 1.4% from $11,697,000  during the first quarter of
1997.  As a percentage of net revenue,  indirect  expense  decreased  from 51.6%
(both on a reported  basis and excluding the impact of CAS) in the first quarter
of 1997 to 45.9% in the first  quarter of 1998.  The decrease was due in part to
the  above-noted  shift in business  mix, the  expansion  of the EOC  reportable
segment, the contraction of the Professional Services reportable segment and the
continued positive impact of cost containment measures.

Adjustment  of  Restructuring  Accrual.  During the first  quarter of 1997,  the
Company reversed an accrual of $75,000 made as part of the restructuring actions
taken in the fourth  quarter of 1996.  The 1996 year end  accrual was revised to
reflect  lower  than  anticipated  costs  associated  with the  abandonment  and
subsequent sublease of certain office space.

                                       11
<PAGE>


Loss on Disposition of Laboratory. During the first quarter of 1997, the Company
completed the sale of CAS to the employees of CAS for  $4,000,000 in cash,  CAS'
promissory notes for $3,219,000  ("CAS Notes") and a continuing  preferred stock
interest in CAS valued at $500,000. The Company paid to CAS $206,000 in cash for
retired  employee  contracts  and for  accelerated  vesting of stock options and
other  non-vested  stock rights.  In  anticipation  of completing  the sale, the
Company  recognized  impairment  in  the  value  of  its  investment  in  CAS of
$3,327,000 at the end of 1996.  As a result of several pre closing  adjustments,
the Company  recognized an additional  loss on  disposition  of CAS in the first
quarter of 1997, of $333,000.

Gain on Sale of Assets.  During the first quarter of 1997, the Company completed
the sale of one of its landfill  gas-to-energy  projects,  including the related
leasehold production rights and associated machinery and equipment.  The Company
recognized a gain on disposition of the project in the first quarter of 1997, of
$826,000.

Income From  Operations.   Income from operations for the first quarter of 1998
was $143,000  compared to $1,317,000 during the comparable period last year.

Interest Income.  The Company recorded  interest income of $168,000 in the first
quarter of 1998 compared to $94,000 in the first  quarter of 1997.  The increase
in interest income in the first quarter of 1998 compared to the first quarter of
1997 was primarily due to the recognition of interest income on the CAS Notes.

Interest  Expense.  The Company  incurred  interest  expense of $293,000 in the 
first  quarter of 1998  compared to $331,000 in the first quarter of 1997.

LIQUIDITY AND CAPITAL RESOURCES

During the first quarter of 1998, the Company's  uses of cash for  non-operating
activities  primarily  consisted  of repayment of debt in the amount of $706,000
and  additions  to property  and  equipment  in the amount of  $395,000;  mainly
computers and field equipment. This was offset by net cash provided by operating
activities during the period of $2,001,000.

In  conjunction  with  the  acquisition  of  OWT,  the  Company  entered  into a
$20,000,000   secured  credit  agreement  with  its  existing  commercial  bank,
replacing  its  previous  $10,000,000  unsecured  line of credit.  Under the new
agreement,  the Company borrowed  $10,000,000 on a term loan basis with interest
at a managed  rate not to exceed the prime rate.  Principal  is to be  amortized
over seven years, but with any unpaid amount finally due and payable on June 30,
2001.  In April 1997,  following  the infusion of cash upon the sale of CAS, the
Company  prepaid,  on an accelerated  basis,  $3,000,000 of the then outstanding
principal  balance of the term loan. The remaining  $10,000,000 under the Credit
Agreement is available for working capital  purposes (with up to $5,000,000 also
being available for non-working capital purposes).  The line of credit component
of the Credit  Agreement  expires on May 31, 1998. The Company  expects to renew
the line of credit  component of the Credit  Agreement  prior to its expiration.
The  Credit  Agreement  contains  provisions  with  respect  to the  payment  of
dividends and the level of capital  expenditures and requires the maintenance of
specific levels of working capital,  tangible net worth and continued  quarterly
profitability.

The Company  believes that its cash on hand and cash generated from  operations,
together  with its  available  bank  financing  will be  sufficient  to meet the
Company's capital needs for at least the next twelve months.

                                       12
<PAGE>



                                      EMCON

                            PART II OTHER INFORMATION

Items 1. - 4.     Not applicable.

Item 5.           Other Information

                  On April 3, 1998, the Company acquired all of the  outstanding
                  equity of Advanced Analytical  Solutions,  Inc. (A2S) for cash
                  of $600,000 and the issuance of 123,077 shares of EMCON common
                  stock.  The former  shareholders  of A2S are also  eligible to
                  receive up to two  additional  earn out  payments  of $150,000
                  (payable in cash and additional  shares of EMCON common stock)
                  in each of the two twelve month periods immediately  following
                  the  acquisition;  which earn out payments  will be treated as
                  additional  purchase  consideration  and  will  be tied to the
                  future financial performance of A2S. The Company also extended
                  a three year full  recourse  secured loan to one of the former
                  A2S shareholders in the principal amount of $225,000. A2S is a
                  nationally   recognized   provider  of   alternative   dispute
                  resolution,  cost  allocation,  cost  recovery and  litigation
                  support  services  around  Superfund  projects with offices in
                  Denver, Colorado and Philadelphia, Pennsylvania.
Item 6.           Exhibits and Reports

      (a)         Exhibits - See Index to Exhibits on Page 15

      (b)         Reports  on Form 8-K - No  reports on Form 8-K were filed with
                  the  Securities  and  Exchange  Commission  during the quarter
                  ended March 31, 1998.

                                       13

<PAGE>


                                      EMCON


                                   SIGNATURES

Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.



Date:   May 8, 1998                       EMCON


                                          \o\  R. Michael Momboisse
                                          -------------------------------------
                                          R. MICHAEL MOMBOISSE
                                          Chief Financial Officer,
                                          Vice President - Legal, and Secretary
                                          (Duly authorized and principal
                                           financial and accounting officer)


                                       14
<PAGE>


                                INDEX TO EXHIBITS
                                                                 Sequentially
   Exhibit                                                         Numbered
   Number                                                            Page
- --------------                                                  ----------------
     2.1       Stock Purchase  Agreement  dated January 30, 1996,      *
               among Organic Waste  Technologies,  Inc.  ("OWT"),
               Registrant and the selling shareholders and option
               holders of OWT,  incorporated  by  reference  from
               Exhibit  2.1 of the  Current  Report  on Form  8-K
               dated March 14, 1996,(the "March 1996 8-K").

     2.2       Asset  Purchase   Agreement  between  Yolo  Energy      *
               Partners,  Inc.,  Yolo  Landfill Gas  Corporation,
               EMCON,  Yolo Neo LLC,  and  Minnesota  Methane LLC
               dated December 31, 1996, incorporated by reference
               from  Exhibit  10.20 of the Annual  Report on Form
               10-K for the fiscal year ended  December  31, 1996
               (the "1996 10-K").

     2.3       Acquisition Agreement between EMCON and its wholly      *
               owned    subsidiary,    Monterey    Landfill   Gas
               Corporation,  and Biomass Energy Partners V, L.P.,
               dated  March 6, 1997,  incorporated  by  reference
               from Exhibit 10.22 of the 1996 10-K.

     2.4       Stock Purchase Agreement dated April 4, 1997 among      *
               Registrant,  Columbia  Analytical  Services,  Inc.
               (`CAS"),  Northwest  Trust as  trustee  of the CAS
               Employee Stock  Ownership Trust and certain senior
               management   employees  of   CAS,incorporated   by
               reference  from  Exhibit  2.4 of the  Registrant's
               Quarterly  Report  on Form  10-Q  for  the  fiscal
               quarter  ended  March 31,  1997 (the  "March  1997
               10-Q").

     2.5       Stock  Purchase  Agreement  dated  April 30,  1997      *
               among  Registrant,  OWT,  National Earth Products,
               Inc.("NEP")  and the selling  stockholders of NEP,
               incorporated  by reference from Exhibit 2.5 of the
               March 1997 10-Q.

     2.6       Agreement   and  Plan  of   Reorganization   among      19
               Registrant,  Advanced Analytical  Solutions,  Inc.
               ("A2S") and certain  other  parties dated April 3,
               1998.

     3.1       Articles    of    Incorporation,    as    amended,      *
               incorporated  by reference from Exhibit 3.1 of the
               Registrant's  Registration  Statement  on Form S-1
               (File No. 33-16337)  effective  September 16, 1987
               (the "Form S-1 Registration Statement").

     3.2       Certificate  of Amendment of Restated  Articles of      *
               Incorporation   as   filed   on  May   24,   1988,
               incorporated  by reference from Exhibit 3.2 of the
               Annual  Report  on Form 10-K for the  fiscal  year
               ended December 31, 1988 (the "1988 10-K").

     3.3       Certificate  of Amendment of Restated  Articles of      *
               Incorporation   as   filed   on  June   4,   1991,
               incorporated  by reference from Exhibit 4.1 of the
               Quarterly  Report  on Form  10-Q  for  the  fiscal
               quarter  ended  June  30,  1991  (the  "June  1991
               10-Q").
  
                                     15

<PAGE>





                                                                  Sequentially
   Exhibit                                                          Numbered
   Number                INDEX TO EXHIBITS (Continued)                Page
- --------------                                                  ----------------
     3.4       Bylaws, as amended, incorporated by reference from       *
               Exhibit 4.2 of the June 1991 10-Q.

     10.1      EMCON  1986   Incentive   Stock  Option  Plan  and       *(1)
               Amendment,  incorporated by reference from Exhibit
               10.15 of the Form S-1 Registration Statement.

     10.2      Form of Agreement pursuant to Salary  Continuation       *(1)
               Plan, incorporated by reference from Exhibit 10.17
               of the Form S-1 Registration Statement.

     10.3      Schedule identifying Agreements pursuant to Salary       *(1)
               Continuation  Plan between  Registrant and certain
               employees,  incorporated by reference from Exhibit
               10.3 of the  Registrant's  Annual  Report  on Form
               10-K for the fiscal year ended  December  31, 1997
               (the "1997 10-K").

     10.4      Form of Indemnity Agreement between the Registrant       *
               and  each  of  the   Registrant's   officers   and
               directors,  incorporated by reference from Exhibit
               10.20 of the  Registrant's  Annual  Report on Form
               10-K for the fiscal year ended  December  31, 1988
               (the "1988 10-K").

     10.5      EMCON  1988   Stock   Option   Plan,   amended  by       *(1)
               shareholder  approval  on May  25,1994,  including
               form  of  Nonqualified   Stock  Option   Agreement
               (Outside  Directors),  incorporated  by  reference
               from Exhibit 10.9 of Registrant's Quarterly Report
               on Form 10-Q for the fiscal quarter ended June 30,
               1994 (the "June 30, 1994 10-Q").

     10.6      EMCON Employee Stock Purchase Plan incorporated by       *(1)
               reference  from Exhibit 10.10 of the  Registrant's
               Quarterly  Report  on Form  10-Q  for  the  fiscal
               quarter ended June 30, 1995.

     10.7      EMCON  Restricted   Stock  Plan   incorporated  by       *(1)
               reference  from Exhibit 10.15 of the Annual Report
               on Form 10-K for the fiscal  year  ended  December
               31, 1990.

     10.8      EMCON Deferred Compensation Plan effective January       *(1)
               1, 1994,  incorporated  by reference  from Exhibit
               10.12 of the  Registrant's  Annual  Report on Form
               10-K for the fiscal year ended  December  31, 1993
               (the "1993 10-K").

     10.9      Trust    Agreement   for   the   EMCON    Deferred       *(1)
               Compensation  Plan and  Salary  Continuation  Plan
               Trust dated February 19, 1994,  between Registrant
               and  Wells  Fargo  Bank,   N.A.   incorporated  by
               reference from Exhibit 10.13 of the 1993 10-K.

     10.10     Agreement  between Eugene M. Herson and Registrant       *(1)
               dated November 30, 1995, incorporated by reference
               from Exhibit 10.21 of  Registrant's  Annual Report
               on Form 10-K for the fiscal  year  ended  December
               31, 1995 (the "1995 10-K").

                                       16
<PAGE>





                                                                   Sequentially
   Exhibit                                                           Numbered
   Number                INDEX TO EXHIBITS (Continued)                 Page
- --------------                                                     -------------
     10.12     Credit  Agreement  between The Bank of California,        *
               N.A.  and  Registrant  dated  February  29,  1996,
               incorporated by reference from Exhibit 10.2 of the
               March 1996 8-K.

     10.13     Security Agreement between The Bank of California,        *
               N.A.  and  Registrant  dated  February  29,  1996,
               incorporated by reference from Exhibit 10.3 of the
               March 1996 8-K.

     10.14     Pledge  Agreement  between The Bank of California,        *
               N.A.  and  Registrant  dated  February  29,  1996,
               incorporated by reference from Exhibit 10.4 of the
               March 1996 8-K.

     10.15     Eurodollar Rate Option Agreement  between The Bank        *
               of California,  N.A. and Registrant dated February
               29, 1996,  incorporated  by reference from Exhibit
               10.5 of the March 1996 8-K.

     10.16     Fixed Rate  Amortization  Option Agreement between        *
               The Bank of California,  N.A and Registrant  dated
               February 29, 1996,  incorporated by reference from
               Exhibit 10.6 of the March 1996 8-K.

     10.17     Note  Agreement  among the  Registrant,  OWT,  and        *
               certain   employees   of  OWT,   incorporated   by
               reference from Exhibit 10.1 of the March 1996 8-K.

     10.18     Rescission   and   Reformation   Agreement   dated        *
               effective  November 1, 1996 among EMCON,  OWT, and
               certain   employees   of  OWT,   incorporated   by
               reference from Exhibit 10.18 of the 1996 10-K.

     10.19     New Note  Agreement  dated  effective  November 1,        *
               1996 among  EMCON,  OWT and certain  employees  of
               OWT,  incorporated by reference from Exhibit 10.19
               of the 1996 10-K.

     10.20     Second   Amendment  to  Credit   Agreement   dated        *
               effective  January  27, 1997 among EMCON and Union
               Bank of California,  N.A.  (formerly  known as The
               Bank  of  California,   N.A.),   incorporated   by
               reference from Exhibit 10.21 of the 1996 10-K.

     10.21     Third   Amendment   to  Credit   Agreement   dated        *
               effective  March 27,  1997  among  EMCON and Union
               Bank of California,  N.A.  (formerly  known as The
               Bank  of  California,   N.A.),   incorporated   by
               reference from Exhibit 10.23 of the 1996 10-K.

     10.22     Convertible  Notes  dated April 30, 1997 issued by        *
               EMCON to Dennis Grimm and Charles  Gearhart in the
               principal  amounts of $400,798.40 and $399,201.60,
               respectively,   incorporated   by  reference  from
               Exhibit 10.22 of the March 1997 10-Q.

                                       17
<PAGE>



                                                                   Sequentially
   Exhibit                                                           Numbered
   Number                 INDEX TO EXHIBITS (Continued)                Page
- --------------                                                    --------------

     10.23     Lease Agreement dated April 4, 1997, between EMCON        *
               and   Columbia    Analytical    Services,    Inc.,
               incorporated  by reference  from Exhibit  10.23 of
               the March 1997 10-Q.

     10.24     Amendment  1997-I to EMCON  Deferred  Compensation        *(1)
               Plan   dated   effective    February   22,   1997,
               incorporated  by reference  from Exhibit  10.24 of
               the Registrant's Quarterly Report on Form 10-Q for
               the fiscal  quarter ended June 30, 1997 (the "June
               30, 1997 10-Q").

     10.25     Fourth   Amendment  to  Credit   Agreement   dated        *
               effective June 24, 1997 among EMCON and Union Bank
               of  California,  N.A.,  incorporated  by reference
               from Exhibit 10.25 of the June 30, 1997 10-Q.

     10.26     Amended and Restated  Agreement  between Eugene M.        *(1)
               Herson  and  Registrant  dated  November  3, 1997,
               incorporated  by reference  from Exhibit  10.26 of
               the 1997 10-K.
 
     10.27     Amended and Restated  Agreement between R. Michael        *(1)
               Momboisse and  Registrant  dated November 3, 1997,
               incorporated  by reference  from Exhibit  10.27 of
               the 1997 10-K.

     10.28     Deferred  Compensation  Plan, Amended and Restated        *(1)
               effective   January  1,  1998,   incorporated   by
               reference from Exhibit 10.28 of the 1997 10-K.

     10.29     Registration  Rights  Agreement among  Registrant,        55
               and the former  shareholders of A2S dated April 3,
               1998.

    10.30      Secured Promissory Note by Timothy M. Keaten dated        63
               April 3, 1998 in the principal amount of $225,000.

     27        Financial Data Schedule, included herein.                 69  

 *  Incorporated by reference
(1)  Management  contract or  compensatory  plan or  arrangement  required to be
     filed as an exhibit to this form pursuant to Item 14(c) of the instructions
     to Form 10-K.

                                       18



                                   EXHIBIT 2.6









                      AGREEMENT AND PLAN OF REORGANIZATION


                                      AMONG


                                      EMCON
                           (a California corporation);

                  ADVANCED ANALYTICAL SOLUTIONS DELAWARE, INC.
                            (a Delaware corporation);

                   ADVANCED ANALYTICAL SOLUTIONS INCORPORATED
                            (a Colorado corporation);

                                       AND

         THE SHAREHOLDERS OF ADVANCED ANALYTICAL SOLUTIONS INCORPORATED
                           (the Colorado Corporation)




                                  April 3, 1998


                                       19
<PAGE>


                      AGREEMENT AND PLAN OF REORGANIZATION


         This AGREEMENT AND PLAN OF REORGANIZATION (the "Agreement") is made and
entered  into as of April 3, 1998 by and among EMCON,  a California  corporation
("EMCON"),  Advanced Analytical Solutions Delaware, Inc., a Delaware corporation
and  wholly-owned  subsidiary of EMCON ("Sub"),  Advanced  Analytical  Solutions
Incorporated,  a  Colorado  corporation  ("A2S")  and  the  Shareholders  of A2S
(collectively, the "A2S Shareholders").


                                    RECITALS

         A.  Pursuant to a statutory  merger of A2S with and into Sub,  with Sub
being  the  surviving  corporation  (the  "Merger"),  among  other  things,  the
outstanding  shares of A2S Common Stock ("A2S Common  Stock") shall be converted
into the right to receive the Merger  Consideration  (as defined in Section 1.6)
upon the terms and subject to the conditions set forth herein.

         B.  A2S,  EMCON  and  the  A2S  Shareholders  desire  to  make  certain
representations  and  warranties  and other  agreements in  connection  with the
Merger.

         C. The parties intend, by executing this Agreement,  to adopt a plan of
reorganization within the meaning of Section 368 of the Internal Revenue Code of
1986, as amended (the  "Code"),  and to cause the Merger to qualify as a forward
triangular  reorganization  under the provisions of Section  368(a)(2)(d) of the
Code.

         NOW,  THEREFORE,  in consideration of the covenants and representations
set forth  herein,  and for other good and valuable  consideration,  the parties
agree as follows:

         1.       The Merger.

                  1.1. The Merger.  At the Effective Time (as defined in Section
1.2) and subject to and upon the terms and  conditions  of this  Agreement,  the
Certificate of Merger attached hereto as Exhibit A (the "Certificate of Merger")
and the applicable provisions of the Delaware General Corporation Law ("Delaware
Law" or "DGL") and the law of the State of Colorado  ("Colorado Law"), A2S shall
be merged with and into Sub, the separate corporate existence of A2S shall cease
and Sub  shall  continue  as the  surviving  corporation.  Sub as the  surviving
corporation  after  the  Merger  is  hereinafter  sometimes  referred  to as the
"Surviving Corporation."

                  1.2. Closing;  Effective Time. The closing of the transactions
contemplated  hereby  (the  "Closing")  shall  take  place on April 3, 1998 (the
"Closing  Date").  The Closing  shall take place at the  offices of  Schlueter &
Associates,  P.C., 1050 17th Street,  Suite 1700, Denver,  Colorado 80265, or at
such other location as the parties hereto agree. In connection with the Closing,
the  parties  hereto  shall  cause the  Merger to be  consummated  by filing the
Certificate of Merger, together with the required officers'  certificates,  with
the  Secretary  of State of each of the  states of  Delaware  and  Colorado,  in
accordance  with the relevant  provisions  of Delaware Law and Colorado Law (the
time of such filing being the "Effective Time").

                                       20
<PAGE>


                  1.3.  Effect of the Merger.  At the Effective Time, the effect
of the Merger shall be as provided in this Agreement,  the Certificate of Merger
and the applicable provisions of Delaware Law and Colorado Law. Without limiting
the generality of the foregoing, and subject thereto, at the Effective Time, all
the property, rights, privileges, powers and franchises of A2S shall vest in the
Surviving Corporation, and all debts, liabilities and duties of A2S shall become
the debts, liabilities and duties of the Surviving Corporation.

                  1.4.     Certificate of Incorporation; Bylaws.

                           (a)      At the Effective  Time, the Certificate of  
Incorporation  of Sub, as in effect  immediately  prior to the  Effective  Time,
shall be the Certificate of  Incorporation  of the Surviving  Corporation  until
thereafter  amended  as  provided  by  Delaware  Law  and  such  Certificate  of
Incorporation.
                           (b)      At the Effective  Time,  the Bylaws of Sub, 
as in effect immediately prior to the Effective Time, shall be the Bylaws of the
Surviving Corporation until thereafter amended.

                  1.5.     Directors  and  Officers.  At the  Effective  Time,  
the directors and officers of Sub immediately  prior to the Effective Time shall
be  the  directors  and  officers  of the  Surviving  Corporation,  until  their
respective successors are duly elected or appointed and qualified.

                  1.6.     Merger Consideration.  By virtue of the Merger, EMCON
shall  deliver the  following consideration (the "Merger Consideration") to the 
A2S Shareholders:

                           (a)      Cash   Consideration.   At  the  Closing,   
EMCON shall deliver to the A2S Shareholders an aggregate of Six Hundred Thousand
Dollars  ($600,000)  (the "Cash  Consideration")  as set forth in  Schedule  1.7
hereto.
                           (b)      EMCON Common Stock. At the Closing,  EMCON  
shall  deliver to the holders of A2S Common Stock (the "A2S  Capital  Stock") an
aggregate  of 123,077  shares of EMCON  Common Stock as set forth in Section 1.7
hereof .
                           (c)      Earnout Payments. During the first two years
following the Closing,  the A2S  Shareholders  shall be eligible to earn Earnout
Payments (as defined in Section  6.1(b)  hereof) up to an aggregate of $300,000,
subject to the terms and conditions of Section 6.1 hereof.

                  1.7.  Effect on Capital Stock At the Effective Time, by virtue
of the Merger and without any action on the part of EMCON, A2S or the holders of
any of the following securities:

                           (a) Conversion  of  A2S  Common  Stock.  Each  share 
of A2S Common Stock issued and  outstanding  immediately  prior to the Effective
Time shall be  converted  and  exchanged,  without any action on the part of the
holders  thereof,  into the right to receive 1.8648 shares of EMCON Common Stock
and  $9.0909  in Cash  Consideration  (the  "Exchange  Ratio"),  as set forth in
Schedule 1.7 hereto.
                                       21
<PAGE>


                           (b)    Adjustments  to Exchange Ratio. The Exchange  
Ratio shall be adjusted to reflect fully the effect of any stock split,  reverse
split,  stock  dividend  (including any dividend or  distribution  of securities
convertible  into  EMCON  Common  Stock or A2S  Common  Stock),  reorganization,
recapitalization  or other like change with respect to EMCON Common Stock or A2S
Common Stock occurring after the date hereof and prior to the Effective Time.

                           (c)      Fractional Shares.  No fraction  of a share
of EMCON Common Stock will be issued,  but in lieu thereof each holder of shares
of A2S Common Stock who would  otherwise be entitled to a fraction of a share of
EMCON Common  Stock (after  aggregating  all  fractional  shares of EMCON Common
Stock to be received by such holder)  shall receive from EMCON an amount of cash
(rounded to the nearest  whole cent) equal to the product of (i) such  fraction,
multiplied by (ii) the Fair Market Value of EMCON Common  Stock.  The term "Fair
Market  Value" shall mean the closing price of EMCON Common Stock on the Closing
Date, as reported on the Nasdaq National  Market (the "Fair Market Value").  The
fractional share interests of each A2S shareholder shall be aggregated,  so that
no A2S shareholder  shall receive cash in respect of fractional  share interests
in an amount greater than the value of one full share of EMCON Common Stock.

                           (d)      Certificate  Legends.  The shares of EMCON 
Common  Stock to be  issued  pursuant  to this  Section  1 shall  not have  been
registered  and shall be  characterized  as  "restricted  securities"  under the
federal  securities  laws, and under such laws such shares may be resold without
registration  under the  Securities  Act or 1933,  as amended  (the  "Securities
Act"), only in certain limited circumstances. Each certificate evidencing shares
of EMCON  Common  Stock to be issued  pursuant to this  Section 1 shall bear the
following legend:
                  "THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED
                  FOR  INVESTMENT  AND  HAVE  NOT  BEEN  REGISTERED   UNDER  THE
                  SECURITIES  ACT OF  1933.  SUCH  SHARES  MAY  NOT BE  SOLD  OR
                  OTHERWISE  TRANSFERRED  IN THE  ABSENCE  OF SUCH  REGISTRATION
                  WITHOUT AN EXEMPTION UNDER THE SECURITIES ACT OR AN OPINION OF
                  LEGAL COUNSEL  REASONABLY  ACCEPTABLE TO THE COMPANY THAT SUCH
                  REGISTRATION IS NOT REQUIRED."

         and any legends required by state securities laws.

                  1.8.     Surrender of Certificates.

                           (a)      EMCON to Provide Common Stock and Cash.  At 
the Closing, EMCON shall deliver to the A2S Shareholders certificates evidencing
the shares of EMCON Common Stock issuable pursuant to Section 1.7(a) in exchange
for shares of A2S Common Stock  outstanding  immediately  prior to the Effective
Time, and (ii) cash in an amount sufficient to permit payment of cash in lieu of
fractional shares.
                           (b)      Transfers of Ownership.  At the Effective  
Time,  the stock transfer books of the A2S shall be closed and there shall be no
further  registration of transfers of A2S Common Stock thereafter on the records
of the A2S. If any  certificate for shares of EMCON Common Stock is to be issued
in a name  other  than that in which the  Certificate  surrendered  in  exchange
therefor is registered,  it will be a condition of the issuance thereof that the
Certificate

                                       22
<PAGE>


so  surrendered  will be  properly  endorsed  and  otherwise  in proper form for
transfer and that the person requesting such exchange will have paid to EMCON or
any agent designated by it any transfer or other taxes required by reason of the
issuance of a  certificate  for shares of EMCON  Common  Stock in any name other
than  that  of  the  registered  holder  of  the  Certificate  surrendered,   or
established to the satisfaction of EMCON or any agent designated by it that such
tax has been paid or is not payable.

                  1.9. No Further  Ownership  Rights in A2S Capital  Stock.  The
Merger Consideration  delivered upon the surrender for exchange of shares of A2S
Capital  Stock in accordance  with the terms hereof  (including  any  dividends,
distributions or cash paid in lieu of fractional shares) shall be deemed to have
been issued in full  satisfaction of all rights pertaining to such shares of A2S
Capital Stock,  and there shall be no further  registration  of transfers on the
records of the Surviving  Corporation  of shares of A2S Capital Stock which were
outstanding  immediately  prior to the Effective  Time.  If, after the Effective
Time,  Certificates  are presented to the Surviving  Corporation for any reason,
they shall be canceled and exchanged as provided in this Section 1.

                  1.10.  Taking of Necessary  Action;  Further  Action.  Each of
EMCON  and A2S  will  take all  such  reasonable  and  lawful  action  as may be
necessary or desirable in order to effectuate the Merger in accordance with this
Agreement as promptly as possible. If, at any time after the Effective Time, any
further  action is  necessary  or  desirable  to carry out the  purposes of this
Agreement  and to vest the  Surviving  Corporation  with full  right,  title and
possession to all assets, property, rights, privileges, powers and franchises of
A2S,  the officers and  directors of EMCON are fully  authorized  in the name of
their  corporation  or  otherwise  to take,  and will take,  all such lawful and
necessary  action,  so  long  as  such  action  is not  inconsistent  with  this
Agreement.

         2.       Conditions to the Merger.

                  2.1.  Conditions  to  Obligations  of Each Party to Effect the
Merger. The respective obligations of each party to this Agreement to consummate
and effect this  Agreement  and the  transactions  contemplated  hereby shall be
subject to the  satisfaction  at or prior to the  Effective  Time of each of the
following  conditions,  any of which may be waived, in writing,  by agreement of
all the parties hereto:

                           (a)      Shareholder Approval.  This  Agreement  and 
the Merger shall be approved and adopted by all of the shareholders of the A2S.

                           (b)      Board  Approval.  This  Agreement  and the
Merger shall be approved and adopted by the Board of Directors of EMCON and A2S.

                           (c)      No Injunctions or Restraints;  Illegality. 
No temporary  restraining  order,  preliminary or permanent  injunction or other
order issued by any court of competent jurisdiction or other legal or regulatory
restraint or prohibition  preventing the consummation of the Merger shall be and
remain in effect, nor shall any proceeding  brought by an administrative  agency
or commission or other governmental  authority or  instrumentality,  domestic or
foreign,  seeking any of the  foregoing be pending,  which would have a Material
Adverse  Effect  on  either  EMCON  or on  EMCON  combined  with  the  Surviving
Corporation  after the Effective  Time, nor shall there be any action taken,  or
any statute, rule, regulation or order enacted, entered, enforced

                                       23

<PAGE>


or deemed  applicable to the Merger,  which makes the consummation of the Merger
illegal.  In the event an injunction or other order shall have been issued, each
party agrees to use its reasonable  diligent  efforts to have such injunction or
other order lifted.
                           (d)      Governmental  Approval.  EMCON and A2S and 
their respective  subsidiaries shall have timely obtained from each Governmental
Entity (as defined below) all approvals, waivers and consents, if any, necessary
for   consummation  of  or  in  connection  with  the  Merger  and  the  several
transactions contemplated hereby, including such approvals, waivers and consents
as may be required  under the  Securities  Act,  under state Blue Sky laws,  and
under HSR other than filings and  approvals  relating to the Merger or affecting
EMCON's  ownership  of A2S or any of its  properties  if failure to obtain  such
approval, waiver or consent would not have a Material Adverse Effect on EMCON or
on EMCON combined with the Surviving Corporation after the Effective Time.

                  2.2.   Additional   Conditions  to  Obligations  of  A2S.  The
obligations of A2S to consummate and effect this Agreement and the  transactions
contemplated  hereby  shall be  subject to the  satisfaction  at or prior to the
Effective Time of each of the following conditions,  any of which may be waived,
in writing, by A2S:

                           (a)      Representations,  Warranties and Covenants.
The  representations and warranties of EMCON in this Agreement shall be true and
correct in all material respects (except for such representations and warranties
that  are  qualified  by  their  terms  by  a  reference  to  materiality  which
representations and warranties as so qualified shall be true in all respects) on
and as of the Effective Time as though such  representations and warranties were
made on and as of such time and EMCON shall have  performed  and complied in all
material  respects  with  all  covenants,  obligations  and  conditions  of this
Agreement  required to be performed  and complied with by it as of the Effective
Time.
                                    (b)     Certificate   of  EMCON.  A2S  shall
have  been  provided  with a  certificate  executed  on  behalf  of EMCON by its
President  and  its  Chief  Financial  Officer  to the  effect  that,  as of the
Effective Time:
                                     (i)    all  representations  and warranties
made by  EMCON  under  this  Agreement  are true and  complete  in all  material
respects (except for such  representations  and warranties that are qualified by
their terms by a reference to materiality which  representations  and warranties
as so qualified shall be true in all respects); and

                                    (ii)    all  covenants,  obligations  and  
conditions  of this  Agreement  to be  performed by EMCON on or before such date
have been so performed in all material respects.

                           (c)      No Material  Adverse  Changes.  Since the 
Balance Sheet Date, there shall not have occurred any material adverse change in
the financial  condition,  properties,  assets  (including  intangible  assets),
liabilities,  business,  operations  or results of  operations  of EMCON and its
subsidiaries, taken as a whole.
                           (d)      Third  Party   Consents.   A2S  shall  have 
been  furnished with evidence  satisfactory  to it of the consent or approval of
those  persons  whose  consent or approval is  required in  connection  with the
Merger.

                                       24

<PAGE>


                           (e)      Injunctions  or  Restraints  on Conduct of 
Business. No temporary restraining order, preliminary or permanent injunction or
other  order  issued by any court of  competent  jurisdiction  or other legal or
regulatory  restraint  provision  limiting  or  restricting  EMCON's  conduct or
operation of the business of EMCON and its  subsidiaries,  following  the Merger
shall be in effect, nor shall any proceeding brought by an administrative agency
or commission or other  Governmental  Entity,  domestic or foreign,  seeking the
foregoing be pending.
                           (f)      Legal  Opinion.  A2S shall have  received a 
legal opinion from EMCON's in house legal counsel in  substantially  the form of
Exhibit B-1.

                  2.3 Additional  Conditions to the  Obligations  of EMCON.  The
obligation of EMCON to consummate and effect this Agreement and the transactions
contemplated  hereby  shall be  subject to the  satisfaction  at or prior to the
Effective Time of each of the following conditions,  any of which may be waived,
in writing, by EMCON:

                           (a)      Representations,  Warranties and Covenants.
The  representations  and warranties of A2S in this Agreement  shall be true and
correct in all material respects (except for such representations and warranties
that  are  qualified  by  their  terms  by  a  reference  to  materiality  which
representations and warranties as so qualified shall be true in all respects) on
and as of the Effective Time as though such  representations and warranties were
made on and as of such time and A2S shall have  performed  and  complied  in all
material  respects  with  all  covenants,  obligations  and  conditions  of this
Agreement  required to be performed  and complied with by it as of the Effective
Time.

                           (b)      Certificate  of  A2S.  EMCON  shall  have  
been provided with a certificate  executed on behalf of A2S by its President and
Treasurer to the effect that, as of the Effective Time:

                                    (i)    all  representations  and  warranties
made by A2S under this Agreement are true and complete in all material  respects
(except for such  representations  and  warranties  that are  qualified by their
terms by a reference to materiality,  which representations and warranties as so
qualified shall be true in all respects); and

                                    (ii)    all  covenants,  obligations  and  
conditions of this  Agreement to be performed by A2S on or before such date have
been so performed in all material respects.

                           (c)      Third  Party Consents.   EMCON  shall  have 
been  furnished with evidence  satisfactory  to it of the consent or approval of
those  persons  whose  consent or approval is  required in  connection  with the
Merger.
                           (d)      Injunctions  or  Restraints  on Conduct of 
Business. No temporary restraining order, preliminary or permanent injunction or
other  order  issued by any court of  competent  jurisdiction  or other legal or
regulatory  restraint  provision  limiting  or  restricting  EMCON's  conduct or
operation  of the  business of A2S and its  subsidiaries,  following  the Merger
shall be in effect, nor shall any proceeding brought by an administrative agency
or commission or other  Governmental  Entity,  domestic or foreign,  seeking the
foregoing be pending.

                                       25

<PAGE>


                           (e)      Legal  Opinion.  EMCON  shall have received 
a legal  opinion from A2S's legal counsel in  substantially  the form of Exhibit
B-2.
                           (f)      No Material  Adverse Changes in Business.  
Since the Balance Sheet Date, there shall not have occurred any material adverse
change in the financial  condition,  properties,  assets  (including  intangible
assets),  liabilities,  business,  operations  or results of  operations of A2S,
taken as a whole.
                           (g)      Employment and Non-Competition  Agreements.
Each  of  William  J.  Hengemihle  and  Christopher  M.  Wittenbrink  (the  "Key
Employees") shall have accepted  employment with Sub pursuant to the terms of an
Employment and Non-Competition  Agreement  substantially in the form attached as
Exhibit C.
                           (h)      Consulting  Agreement.  Timothy M.  Keaten  
shall  have  entered  a  short-term  consulting  agreement  with  the  Surviving
Corporation  in the form  attached  hereto as  Exhibit  D and a  non-competition
agreement  with terms  substantially  the same as those  entered into by the Key
Employees.
                           (i)      No Material  Adverse  Changes.  Except for 
the funds  borrowed from Wells Fargo Bank,  N.A. under the A2S line of credit to
purchase the  promissory  note issued by Marty  Cuerdon to Bonnie  Cuerdon dated
February 20, 1993 (the  "Cuerdon  Promissory  Note") (which was disclosed to and
consented  to by EMCON),  there shall not have  occurred  any  material  adverse
change  (including,  but not limited to, cash  distributions or decreases in net
assets) in the A2S Balance Sheet (as defined in Section 0 hereof) since February
28, 1998, other than in the ordinary course of business and consistent with past
practice.
                           (j)      Release of Security  Interests.  Except for 
the security interests that exist under the credit arrangements  between A2S and
Well Fargo  Bank,  N.A.,  and leases or purchase  money  security  interests  in
certain  equipment of A2S, the A2S  Shareholders  shall have  delivered to EMCON
written evidence legally sufficient to terminate any and all security interests,
liens or other encumbrances on the outstanding shares of A2S Common Stock or the
assets of A2S.

         3.  Representations  and Warranties of the A2S Shareholders.  Except as
disclosed  in a  document  of  even  date  herewith  and  delivered  by the  A2S
Shareholders  to EMCON prior to the execution and delivery of this Agreement and
referring to the  representations  and  warranties in this  Agreement  (the "A2S
Disclosure  Schedule"),  each A2S  Shareholder,  as to himself,  represents  and
warrants to EMCON as follows (any representation or warranty of A2S herein shall
be deemed to be a representation and warranty of each A2S Shareholder):

                  3.1.  Organization,  Standing and Power.  A2S is a corporation
duly  organized,  validly  existing and in good  standing  under the laws of its
jurisdiction of organization.  A2S has the corporate power to own its properties
and to carry on its business as now being  conducted and is duly qualified to do
business and is in good standing in each jurisdiction in which the failure to be
so qualified and in good standing  would have a Material  Adverse Effect on A2S.
A2S has delivered a true and correct copy of the Articles of  Incorporation  and
Bylaws or other  charter  documents,  as  applicable,  of A2S each as amended to
date, to EMCON. A2S is not in violation of any of the provisions of its Articles
of Incorporation or Bylaws or equivalent  organizational documents. A2S does not
directly or  indirectly  own any equity or similar  interest in, or any interest
convertible or exchangeable or exercisable  for, any equity or similar  interest
in, any corporation, partnership, joint venture or other business association or
entity.

                                       26
<PAGE>




                  3.2.  Authority.  As of the  Closing  Date,  A2S will have all
requisite  corporate  power and  authority to enter into this  Agreement  and to
consummate the  transactions  contemplated  hereby.  As of the Closing Date, the
execution  and  delivery  of  this  Agreement  and  the   consummation   of  the
transactions contemplated hereby will have been duly authorized by all necessary
corporate  action on the part of A2S. The  affirmative  vote of the holders of a
majority of the shares of A2S Common  Stock  outstanding  on the record date for
the written consent of shareholders  relating to this Agreement is the only vote
of the holders of any of A2S's Capital  Stock  necessary  under  Colorado Law to
approve this  Agreement  and the  transactions  contemplated  hereby.  As of the
Closing Date, the Board of Directors of A2S shall have (i) unanimously  approved
this Agreement and the Merger, (ii) determined that in its opinion the Merger is
in the best interests of the  shareholders  of A2S and is on terms that are fair
to such  shareholders and (iii) recommended that the shareholders of A2S approve
this  Agreement  and the  Merger.  This  Agreement  has been duly  executed  and
delivered  by A2S and  constitutes  the  valid  and  binding  obligation  of A2S
enforceable  against  A2S  in  accordance  with  its  terms,  except  that  such
enforceability  may be limited by  bankruptcy,  insolvency,  moratorium or other
similar  laws  affecting  or relating to  creditors'  rights  generally,  and is
subject to general  principles  of equity.  The  execution  and delivery of this
Agreement by A2S does not, and the consummation of the transactions contemplated
hereby will not conflict  with,  or result in any violation of, or default under
(with or without  notice or lapse of time, or both),  or give rise to a right of
termination,  cancellation or acceleration of any material obligation or loss of
any material benefit under (i) any provision of the Articles of Incorporation or
Bylaws of A2S, as amended,  or (ii) any  material  mortgage,  indenture,  lease,
contract  or other  agreement  or  instrument,  permit,  concession,  franchise,
license,  judgment,  order, decree, statute, law, ordinance,  rule or regulation
applicable  to A2S or any of its  properties  or assets.  No consent,  approval,
order or  authorization  of, or  registration,  declaration  or filing with, any
court,  administrative  agency or commission or other governmental  authority or
instrumentality ("Governmental Entity") is required by or with respect to A2S in
connection with the execution and delivery of this Agreement or the consummation
of the  transactions  contemplated  hereby,  except  for (i) the  filing  of the
Certificate of Merger,  together with the required  officers'  certificates,  as
provided  in  Section  0,  (ii)  filings  required  under  Regulation  D of  the
Securities Act of 1933, (iii) such consents, approvals, orders,  authorizations,
registrations,  declarations  and  filings as may be required  under  applicable
state securities laws and the securities laws of any foreign country;  (iv) such
filings as may be required under the  Hart-Scott-Rodino  Antitrust  Improvements
Act of 1976, as amended  ("HSR");  and (v) such other consents,  authorizations,
filings,  approvals and registrations  which, if not obtained or made, would not
have a Material Adverse Effect on A2S and would not prevent, or materially alter
or delay any of the transactions contemplated by this Agreement.

                  3.3.  Governmental   Authorization.   A2S  has  obtained  each
federal, state, county, local or foreign governmental consent,  license, permit,
grant, or other authorization of a Governmental Entity (i) pursuant to which A2S
currently  operates or holds any interest in any of its  properties or (ii) that
is  required  for the  operation  of A2S's  business  or the holding of any such
interest  and all of such  authorizations  are in full force and  effect  except
where the failure to obtain or have any such authorizations could not reasonably
be expected to have a Material Adverse Effect on A2S.

                  3.4. Title to Property.  A2S has good and marketable  title to
all of its  properties,  interests in properties and assets,  real and personal,
reflected in the A2S Balance Sheet or acquired  after the A2S Balance Sheet Date
(except properties, interests in properties and assets

                                       27

<PAGE>


sold or otherwise  disposed of since the A2S Balance  Sheet Date in the ordinary
course of business),  and with respect to leased  properties  and assets,  valid
leasehold interests therein,  free and clear of all mortgages,  liens,  pledges,
charges or encumbrances of any kind or character, except (i) the lien of current
taxes not yet due and  payable,  (ii)  such  imperfections  of title,  liens and
easements as do not and will not  materially  detract from or interfere with the
use  of the  properties  subject  thereto  or  affected  thereby,  or  otherwise
materially impair business operations  involving such properties and (iii) liens
securing  debt which is  reflected  on the A2S Balance  Sheet.  The property and
equipment of A2S that are used in the  operations of its  businesses  are in all
material respects in good operating condition and repair, subject to normal wear
and tear. All material properties used in the operations of A2S are reflected in
the A2S Balance Sheet to the extent  generally  accepted  accounting  principles
require the same to be reflected. All leases to which A2S is a party are in full
force and effect and are valid, binding and enforceable in accordance with their
respective terms, except as such enforceability may be limited by (i) bankruptcy
laws and other  similar laws  affecting  creditors'  rights  generally  and (ii)
general principles of equity,  regardless of whether asserted in a proceeding in
equity or at law. True and correct  copies of all such leases have been provided
to EMCON.  A2S owns no real  property.  True and correct copies of all such real
property leases have been provided to EMCON.

                  3.5. Capital  Structure.  The authorized  capital stock of A2S
consists  of  200,000  shares  of A2S  Common  Stock and  100,000  shares of A2S
Preferred  Stock.  As of the Closing Date,  there will be issued and outstanding
66,000  shares of A2S Common  Stock and no shares of A2S  Preferred  Stock.  All
outstanding  shares of A2S Common  Stock are duly  authorized,  validly  issued,
fully paid and  non-assessable  and are free of any liens or encumbrances  other
than any liens or encumbrances  created by or imposed upon the holders  thereof,
and are not subject to preemptive  rights or rights of first refusal  created by
statute,  the  Articles of  Incorporation  or Bylaws of A2S or any  agreement to
which A2S is a party or by which it is bound.

                           Except for the rights created  pursuant to this  
Agreement,  there are no other options,  warrants, calls, rights, commitments or
agreements  of any  character  to  which  A2S is a party or by which it is bound
obligating  A2S to issue,  deliver,  sell,  repurchase  or redeem or cause to be
issued,  delivered,  sold,  repurchased  or redeemed,  any shares of A2S Capital
Stock or obligating A2S to grant, extend,  accelerate the vesting of, change the
price of, or  otherwise  amend or enter  into any such  option,  warrant,  call,
right,  commitment or agreement.  There are no other  contracts,  commitments or
agreements  relating  to voting,  purchase  or sale of A2S's  capital  stock (i)
between or among A2S and any of its  shareholders  and (ii) to A2S's  knowledge,
between or among any of A2S's shareholders. All shares of outstanding A2S Common
Stock were issued in compliance with all applicable federal and state securities
laws.
                  3.6.  Financial  Statements.  A2S has  delivered  to EMCON its
unaudited  financial  statements for each of the fiscal years ended December 31,
1997 and December 31, 1996,  respectively,  and interim financial statements for
the two month  period  ended  February 28, 1998  (collectively,  the  "Financial
Statements").  The Financial Statements are complete and correct in all material
respects and have been prepared in accordance with generally accepted accounting
principles  (except that the  Financial  Statements  do not have notes  thereto)
applied on a consistent  basis  throughout  the periods  indicated and with each
other.  The Financial  Statements  fairly  present the  financial  condition and
operating  results  of A2S as of the  dates,  and  for  the  periods,  indicated
therein,  subject to normal end of period  adjustments.  A2S  maintains and will
continue  to  maintain  a  standard   system  of  accounting   established   and
administered in accordance with generally accepted accounting principles.

                                       28
<PAGE>


                  3.7. Absence of Certain Changes.  Since February 28, 1998 (the
"A2S Balance Sheet Date"), A2S has conducted its business in the ordinary course
consistent with past practice and there has not occurred:  (i) any change, event
or  condition  (whether or not covered by  insurance)  that has  resulted in, or
might  reasonably  be expected to result in, a Material  Adverse  Effect to A2S;
(ii) any  acquisition,  sale or transfer of any material asset of A2S other than
in the ordinary course of business and consistent with past practice;  (iii) any
change in accounting methods or practices  (including any change in depreciation
or  amortization  policies or rates) by A2S or any  revaluation by A2S of any of
its assets;  (iv) any  declaration,  setting aside,  or payment of a dividend or
other  distribution  with respect to the shares of A2S or any direct or indirect
redemption, purchase or other acquisition by A2S of any of its shares of capital
stock; (v) any material contract entered into by A2S, other than in the ordinary
course of business  and as  provided  to EMCON,  or any  material  amendment  or
termination of, or default under, any material  contract to which A2S is a party
or by which it is  bound;  (vi) any  amendment  or  change  to the  Articles  of
Incorporation  or Bylaws of A2S;  (vii) any increase in or  modification  of the
compensation  or  benefits  payable  or to become  payable  by A2S to any of its
directors or employees;  or (viii) any negotiation or agreement by A2S to do any
of the things  described in the preceding  clauses (i) through (vii) (other than
negotiations  with  EMCON and its  representatives  regarding  the  transactions
contemplated by this Agreement). At the Effective Time, there will be no accrued
but unpaid dividends on shares of A2S's capital stock.

                  3.8. Absence of Undisclosed  Liabilities.  A2S has no material
obligations  or  liabilities  of any  nature  (matured  or  unmatured,  fixed or
contingent)  other than (i) those set forth or  adequately  provided  for in the
Balance Sheet for the period ended February 28, 1998 (the "A2S Balance  Sheet"),
(ii) those  incurred in the  ordinary  course of business and not required to be
set  forth  in  the  A2S  Balance  Sheet  under  generally  accepted  accounting
principles,  (iii) those  incurred in the ordinary  course of business since the
A2S  Balance  Sheet  Date and  consistent  with past  practice;  and (iv)  those
incurred in connection with the execution of this Agreement.

                  3.9.  Litigation.  There is no private or governmental action,
suit, proceeding, claim, arbitration or investigation pending before any agency,
court or tribunal,  foreign or domestic, or, to the knowledge of A2S, threatened
against A2S or any of their  respective  properties  or any of their  respective
officers or directors (in their capacities as such) that, individually or in the
aggregate,  could  reasonably be expected to have a Material  Adverse  Effect on
A2S. There is no judgment,  decree or order against A2S, or, to the knowledge of
A2S,  any of their  respective  directors or officers  (in their  capacities  as
such),  that could  prevent,  enjoin,  or  materially  alter or delay any of the
transactions  contemplated  by this  Agreement,  or  that  could  reasonably  be
expected to have a Material  Adverse  Effect on A2S. All litigation to which A2S
is a party  (or,  to the  knowledge  of A2S,  threatened  to  become a party) is
disclosed in the A2S Disclosure Schedule.

                  3.10.  Restrictions  on  Business  Activities.   There  is  no
agreement,  judgment,  injunction, order or decree binding upon A2S which has or
could  reasonably  be expected to have the effect of  prohibiting  or materially
impairing any current or future  business  practice of A2S, any  acquisition  of
property by A2S or the conduct of business by A2S as  currently  conducted or as
proposed to be conducted by A2S.

                  3.11.    Intellectual Property.

                           (a)      A2S owns and has good and marketable title 
to, or is licensed or otherwise possesses legally enforceable rights to use, all
patents, patent applications, trademarks,

                                       29

<PAGE>


                           trade names,  service marks,  copyrights (whether  
registered or unregistered),  and any applications therefor, maskworks, maskwork
applications,  net  lists,  schematics,  technology,  know-how,  trade  secrets,
inventory,  ideas,  algorithms,   processes,   computer  software  programs  and
applications  (in both  source  code and object  code  form),  client  lists and
tangible or  intangible  proprietary  information  and  material  ("Intellectual
Property") that are used or currently proposed to be used in the business of A2S
as currently  conducted  or as proposed to be  conducted  by A2S,  except to the
extent that the failure to have such rights has not had and would not reasonably
be expected to have a Material Adverse Effect on A2S. A2S is the exclusive owner
of all  Intellectual  Property.  A2S has not  licensed  any of the  Intellectual
Property on an exclusive basis.

                           (b)    All patents, registered  trademarks,  service 
marks  and  copyrights  held  by  A2S  are  valid  and  subsisting.  A2S  is not
infringing, misappropriating or making unlawful use of, and has not received any
notice or other communication (in writing or otherwise) of any actual,  alleged,
possible or  potential  infringement,  misappropriation  or unlawful  use of any
proprietary asset owned or used by any third party. A2S (i) has not been sued in
any suit,  action or proceeding  which involves a claim of  infringement  of any
patents, trademarks,  service marks, copyrights or violation of any trade secret
or other  proprietary  right of any third  party;  and (ii) has not  brought any
action,  suit or proceeding for infringement of Intellectual  Property or breach
of any license or agreement  involving  Intellectual  Property against any third
party.
                           (c)     All  current and  former officers,  employees
and  consultants  of A2S  have  executed  and  delivered  to  A2S  an  agreement
(containing  no  exceptions  or  exclusions  from  the  scope  of its  coverage)
regarding the protection of proprietary information and the assignment to A2S of
any  Intellectual  Property  arising  from  services  performed  for A2S by such
persons, the form of which has been supplied to EMCON.

                  3.12.  Interested Party  Transactions.  A2S is not indebted to
any  director,  officer,  employee  or agent of A2S  (except  for amounts due as
normal salaries and bonuses and in reimbursement of ordinary  expenses),  and no
such person is indebted to A2S.

                  3.13.  Minute Books. The minute books of A2S made available to
EMCON  contain a complete and accurate  summary of all meetings of directors and
shareholders  or actions by written consent since the time of  incorporation  of
A2S through the date of this Agreement, and reflect all transactions referred to
in such minutes accurately in all material respects.

                  3.14. Complete Copies of Materials.  A2S has delivered or made
available true and complete  copies of each document which has been requested by
EMCON or its counsel in  connection  with their legal and  accounting  review of
A2S.

                  3.15.  Material  Contracts.  All the  material  contracts  and
agreements  to which A2S is a party are listed in  Schedule  3.15  hereto.  With
respect to each agreement so listed: (i) the agreement is legal, valid,  binding
and  enforceable  and in full force and effect with respect to A2S, and to A2S's
knowledge is legal,  valid,  binding,  enforceable  and in full force and effect
with respect to each other party  thereto,  in either case subject to the effect
of  bankruptcy,  insolvency,  moratorium  or other  similar laws  affecting  the
enforcement of creditors'  rights  generally and except as the  availability  of
equitable  remedies  may be limited by general  principles  of equity;  (ii) the
agreement will continue to be legal, valid,  binding and enforceable and in full
force and effect immediately  following the Closing in accordance with the terms
thereof as in effect prior to the Closing,  subject to the effect of bankruptcy,
insolvency,  moratorium  or other  similar laws  affecting  the  enforcement  of
creditors' rights generally and except as the availability of equitable

                                       30
<PAGE>


remedies may be limited by general  principles of equity;  and (iii) neither the
A2S nor, to A2S's  knowledge,  any other party, is in breach or default,  and no
event has occurred which with notice or lapse of time would  constitute a breach
of default by A2S or, to A2S's  knowledge,  by any such other  party,  or permit
termination,  modification or  acceleration,  under the agreement.  A2S is not a
party to any material oral contract,  agreement or other  arrangement other than
as may be disclosed in Schedule 3.15 hereto.

                  3.16. Accounts  Receivable.  Subject to any reserves set forth
in the  Financial  Statements,  the accounts  receivable  shown on the Financial
Statements  represent and will represent  bona fide claims  against  debtors for
sales and other charges, are collectible in accordance with their terms at their
recorded  amounts  and are not  subject to  discount  except for normal cash and
immaterial  trade  discounts.  The amount  carried  for  doubtful  accounts  and
allowances  disclosed in the  Financial  Statements is sufficient to provide for
any losses which may be sustained on revaluation of the receivables.

                  3.17  Customers  and  Suppliers.  As of the  date  hereof,  no
customer which  individually  accounted for more than 5% of A2S's gross revenues
during the 12 month period preceding the date hereof and no supplier of A2S, has
canceled or otherwise terminated, or made any written threat to A2S to cancel or
otherwise  terminate  its  relationship  with A2S or has at any time on or after
February 28, 1998  decreased  materially  its services or supplies to A2S in the
case of any such  supplier,  or its usage of the  services or products of A2S in
the case of such customer, and to A2S's knowledge,  no such supplier or customer
has  indicated  either  orally or in writing  that it will  cancel or  otherwise
terminate its  relationship  with A2S or to decrease  materially its services or
supplies to A2S or its usage of the services or products of A2S, as the case may
be. A2S has not knowingly  breached,  so as to provide a benefit to A2S that was
not intended by the parties,  any agreement  with, or engaged in any  fraudulent
conduct with respect to, any customer or supplier of A2S.

                  3.18.  Employees and Consultants.  The A2S Disclosure Schedule
or a  letter  delivered  to  EMCON by A2S  contains  a list of the  names of all
employees and  consultants of A2S,  their  respective  salaries or wages,  other
compensation and dates of employment and positions.

                  3.19.    Environmental Matters

                           (a)  The following terms shall be defined as follows:

                                    (i)     "Environmental  Laws"  shall  mean
any  federal,  state or  local  laws,  ordinances,  codes,  regulations,  rules,
policies  and  orders  that  are  intended  to  assure  the  protection  of  the
environment,  or that classify,  regulate,  call for the remediation of, require
reporting  with  respect to, or list or define air,  water,  groundwater,  solid
waste,  hazardous  or  toxic  substances,   materials,   wastes,  pollutants  or
contaminants,  or which are intended to assure the safety of employees,  workers
or other persons, including the public.

                                     (ii)   "Hazardous  Materials"  shall  mean
any  toxic  or  hazardous  substance,  material  or waste  or any  pollutant  or
contaminant,  or  infectious  or  radioactive  substance or material,  including
without  limitation,  those  substances,  materials  and  wastes  defined  in or
regulated under any Environmental Laws.

                           (b)      A2S is not and has not been in violation of 
any  Environmental  Law relating to the properties or facilities of A2S at which
any part of A2S's business is or has been

                                       31

<PAGE>

conducted.  A2S has not used, generated,  manufactured or stored on or under any
part of its  properties or facilities at which any part of A2S's  business is or
has been  conducted,  or transported to or from any part thereof,  any Hazardous
Materials in violation of any applicable  Environmental Laws. There has not been
any presence,  disposal, or release of any Hazardous Materials on, from or under
any part of A2S's  properties or facilities at which any part of A2S's  business
is  or  has  been  conducted.  No  civil,  criminal  or  administrative  action,
proceeding  or  investigation  is pending  against  A2S, or to A2S's  knowledge,
threatened against A2S, and A2S is not aware of any facts or circumstances which
could  form  the  basis  for  assertion  of  a  claim  or  liability,  regarding
non-compliance with Environmental Laws relating to A2S's business.

                  3.20.  Taxes. As used in this Agreement,  the terms "Tax" and,
collectively,  "Taxes"  mean any and all  federal,  state and local taxes of any
country,  assessments and other governmental  charges,  duties,  impositions and
liabilities,  including taxes based upon or measured by gross receipts,  income,
profits,  sales,  use and  occupation,  and value added,  ad valorem,  transfer,
franchise,  withholding,  payroll,  recapture,  employment,  excise and property
taxes, together with all interest,  penalties and additions imposed with respect
to such amounts and any obligations  under any agreements or  arrangements  with
any other person with respect to such amounts and  including  any  liability for
taxes of a predecessor entity.

                           (a)      A2S  has  prepared  and  timely  filed  all
returns, estimates, information statements and reports required to be filed with
any taxing  authority  ("Returns")  relating to any and all Taxes  concerning or
attributable  to A2S or its  operations  with  respect  to Taxes for any  period
ending on or before the  Closing  Date and such  Returns are true and correct in
all  material  respects  and have been  completed  in all  material  respects in
accordance  with  applicable  law or an adequate  reserve has been made for such
Taxes on the A2S Balance Sheet.

                           (b)      A2S, as of the Closing Date:  (i) will have 
paid all Taxes shown to be payable on such  Returns  covered by Section 3.20 (a)
and (ii) will have withheld with respect to its employees all Taxes  required to
be withheld.

                           (c)      There is no Tax  deficiency  outstanding or 
assessed or, to the best of A2S's  knowledge,  proposed  against A2S that is not
reflected  as a liability  on the A2S  Balance  Sheet nor has A2S  executed  any
agreements or waivers  extending any statute of  limitations on or extending the
period for the assessment or collection of any Tax.

                           (d)      A2S has no material liabilities for unpaid 
Taxes  that  have  not  been  accrued for or reserved on the A2S Balance  Sheet,
whether asserted or unasserted, contingent or otherwise.

                           (e)  A2S is not a party to any tax-sharing  agreement
or  similar  arrangement with  any other  party, or any contractual  obligation
to  pay  any  Tax obligations of, or with  respect to  any transaction  relating
to, any other person or to  indemnify  any other person with respect to any Tax.

                           (f)      A2S's Returns have never been audited by a 
government  or  taxing  authority,  nor is any  such  audit in  process  or
pending,  and A2S  has not been notified of any request for such an audit or
other examination.
                           (g)     A2S has never been a member of an  affiliated
group of  corporations  filing a consolidated federal income tax return.

                                       32
<PAGE>



                           (h)      A2S  is not aware of any plan or  intention 
on  the  part of its  shareholders  to  engage  in  any  sale or sales of EMCON
Common Stock to be received pursuant to the Merger. For purposes of this Section
3.20  (h),  the  term  "sale"  shall  include  any  sale,  exchange,   transfer,
distribution,  redemption  or reduction in any way of the risk of ownership  (by
short sale or otherwise), or other disposition, whether direct or indirect.

                           (i)      A2S has made available to EMCON  copies of 
all Returns  filed for all periods since its inception.

                           (j)     A2S has not filed any consent agreement under
Section 341(f)  of the Code or agreed to have Section 341(f)(4) apply to any 
disposition of assets owned by A2S.

                           (k)      A2S has not been at any time a United States
Real Property Holding Corporation within the meaning of Section 897(c)(2) of the
Code.

                           (l)    A2S is not a party to any contract, agreement,

plan or  arrangement,  including  but  not  limited to the  provisions of this
Agreement, covering any employee or former employee of A2S that, individually or
collectively,  could give rise to the  payment  of any amount  that would not be
deductible by A2S as an expense under applicable law.

                           (m)     A2S does not currently and has never met the 
criteria of a Qualified  Personal Service Corporation as defined in the Internal
Revenue Code Section  448(d)(2)and Treasury Regulations Section 1.448-1T(e)(3).

                  3.21.    Employee Benefit Plans.

                           (a)     Schedule 3.21 lists, with respect to A2S and 
any  trade  or business (whether or not  incorporated)  which is treated  as  a
single  employer with A2S (an "ERISA  Affiliate")  within the meaning of Section
414(b),  (c),(m) or (o) of the Code, (i) all material employee benefit plans (as
defined in Section 3(3) of the Employee  Retirement Income Security Act of 1974,
as amended  ("ERISA")),  (ii) each loan to a  non-officer  employee in excess of
$10,000,  loans to officers and directors and any stock option,  stock purchase,
phantom stock, stock appreciation  right,  supplemental  retirement,  severance,
sabbatical,  medical,  dental,  vision care,  disability,  employee  relocation,
cafeteria  benefit (Code Section 125) or dependent care (Code Section 129), life
insurance  or accident  insurance  plans,  programs or  arrangements,  (iii) all
bonus,  pension,  profit sharing,  savings,  deferred  compensation or incentive
plans,  programs or  arrangements,  (iv) other fringe or employee benefit plans,
programs or arrangements  that apply to senior management of A2S and that do not
generally  apply to all employees,  and (v) any current or former  employment or
executive  compensation  or severance  agreements,  written or otherwise,  as to
which  unsatisfied  obligations  of A2S of greater than  $10,000  remain for the
benefit  of or  relating  to,  any  present or former  employee,  consultant  or
director of A2S (together, the "A2S Employee Plans").

                           (b)      A2S has  furnished to EMCON a copy of  each
of  the  A2S  Employee  Plans and related  plan  documents  (including  trust
documents,  insurance  policies or contracts,  employee  booklets,  summary plan
descriptions and other  authorizing  documents,  and, to the extent still in its
possession, any material employee communications relating thereto) and has, with
respect  to  each  A2S  Employee  Plan  which  is  subject  to  ERISA  reporting
requirements,  provided copies of the Form 5500 reports filed for the last three
plan years. Any A2S Employee Plan

                                       33
<PAGE>


intended  to  be  qualified  under  Section  401(a)  of  the  Code  has  either
obtained from the Internal Revenue Service a favorable  determination  letter as
to its qualified  status under the Code,  including  all  amendments to the Code
effected  by the Tax  Reform  Act of 1986  and  subsequent  legislation,  or has
applied to the Internal Revenue Service for such a determination letter prior to
the expiration of the requisite period under applicable Treasury  Regulations or
Internal Revenue Service pronouncements in which to apply for such determination
letter and to make any amendments necessary to obtain a favorable determination,
or has  been  established  under a  standardized  prototype  plan  for  which an
Internal  Revenue  Service  opinion letter has been obtained by the plan sponsor
and is valid as to the adopting employer.  A2S has also furnished EMCON with the
most recent Internal Revenue Service determination or opinion letter issued with
respect to each such A2S  Employee  Plan,  and  nothing has  occurred  since the
issuance of each such letter  which  could  reasonably  be expected to cause the
loss of the  tax-qualified  status  of any A2S  Employee  Plan  subject  to Code
Section 401(a).

                           (c)    (i) None of the A2S  Employee Plans  promises
or  provides  retiree  medical or  other  retiree  welfare  benefits  to  any
person; (ii) there has been no "prohibited transaction," as such term is defined
in Section 406 of ERISA and Section  4975 of the Code,  with  respect to any A2S
Employee Plan, which could  reasonably be expected to have, in the aggregate,  a
Material Adverse Effect;  (iii) each A2S Employee Plan has been  administered in
accordance with its terms and in compliance with the requirements  prescribed by
any and all  statutes,  rules and  regulations  (including  ERISA and the Code),
except as would not have, in the aggregate,  a Material Adverse Effect,  and A2S
and each subsidiary or ERISA  Affiliate have performed all material  obligations
required to be  performed  by them  under,  are not in any  material  respect in
default  under or violation of and have no knowledge of any material  default or
violation by any other party to, any of the A2S Employee Plans; (iv) neither A2S
or ERISA  Affiliate is subject to any liability or penalty  under  Sections 4976
through  4980 of the  Code or Title I of ERISA  with  respect  to any of the A2S
Employee  Plans;  (v) all material  contributions  required to be made by A2S or
ERISA  Affiliate to any A2S Employee  Plan have been made on or before their due
dates and a  reasonable  amount has been accrued for  contributions  to each A2S
Employee Plan for the current plan years; (vi) with respect to each A2S Employee
Plan,  no  "reportable  event"  within  the  meaning  of  Section  4043 of ERISA
(excluding any such event for which the thirty (30) day notice  requirement  has
been  waived  under the  regulations  to  Section  4043 of ERISA)  nor any event
described in Section 4062, 4063 or 4041 or ERISA has occurred;  and (vii) no A2S
Employee Plan is covered by, and neither A2S or ERISA  Affiliate has incurred or
expects to incur any  liability  under  Title IV of ERISA or Section  412 of the
Code.  With  respect  to each A2S  Employee  Plan  subject to ERISA as either an
employee pension plan within the meaning of Section 3(2) of ERISA or an employee
welfare  benefit  plan  within the  meaning of  Section  3(l) of ERISA,  A2S has
prepared  in good  faith and timely  filed all  requisite  governmental  reports
(which were true and correct as of the date filed) and has  properly  and timely
filed and distributed or posted all notices and reports to employees required to
be filed,  distributed or posted with respect to each such A2S Employee Plan. No
suit, administrative proceeding, action or other litigation has been brought, or
to the knowledge of A2S is  threatened,  against or with respect to any such A2S
Employee  Plan,  including  any audit or  inquiry  by the IRS or  United  States
Department of Labor.  Neither A2S or other ERISA Affiliate is a party to, or has
made any  contribution  to or  otherwise  incurred  any  obligation  under,  any
"multiemployer plan" as defined in Section 3(37) of ERISA.

                           (d)      With  respect to each A2S Employee  Plan,  
A2S  and  each  of its United States  subsidiaries  have  complied  with (i) the
applicable  health care  continuation and notice  provisions of the Consolidated
Omnibus Budget Reconciliation Act of 1985 ("COBRA").

                                       34
<PAGE>

and   the   proposed    regulations   thereunder   and  (ii)   the   applicable
requirements  of the Family  Leave Act of 1993 and the  regulations  thereunder,
except to the extent  that such  failure to comply  would not in the  aggregate,
have a Material Adverse Effect.

                           (e)      The  consummation of the  transactions  
contemplated  by  this  Agreement will  not (i) entitle  any  current  or former
employee  or other  service  provider  of A2S or any other  ERISA  Affiliate  to
severance  benefits  or  any  other  payment  (including,   without  limitation,
unemployment  compensation,  golden  parachute  or bonus),  except as  expressly
provided in this Agreement or (ii)  accelerate the time of payment or vesting of
any such benefits,  or increase the amount of compensation due any such employee
or service provider.

                           (f)      There  has been no amendment  to,  written 
interpretation  or  announcement  (whether or  not  written)  by  A2S  or  other
ERISA Affiliate  relating to, or change in  participation or coverage under, any
A2S Employee  Plan which would  materially  increase the expense of  maintaining
such Plan above the level of expense  incurred with respect to that Plan for the
most recent fiscal year included in A2S's financial statements.

                  3.22.  Employee  Matters.   A2S  is  in  compliance  with  all
currently   applicable  laws  and  regulations   respecting   discrimination  in
employment,  terms and conditions of employment,  wages,  hours and occupational
safety and health and employment practices, except for such noncompliance as has
not and would not  reasonably be expected to have had a Material  Adverse Effect
on A2S,  and is not engaged in any unfair labor  practice.  There are no pending
claims  against A2S under any workers'  compensation  plan or policy or for long
term disability. A2S has no material obligations under COBRA with respect to any
former employees or beneficiaries  thereunder.  There are no proceedings pending
or, to the knowledge of A2S,  threatened,  between A2S and its employees,  which
proceedings  have or could  reasonably  be expected  to have a Material  Adverse
Effect on A2S.  A2S is not a party to any  collective  bargaining  agreement  or
other labor union contract nor does A2S know of any activities or proceedings of
any labor union to organize its  employees.  There has been no claim against A2S
based on actual or alleged  race,  age, sex,  disability or other  harassment or
discrimination,  or similar tortious conduct, nor, to A2S's knowledge,  is there
any basis for such claim.  In addition,  A2S has provided all employees with all
relocation  benefits,  stock  options,  bonuses  and  incentives,  and all other
compensation earned up through the date of this Agreement.

                  3.23. Insurance.  Schedule 3.23 lists each policy of insurance
and bonds held by A2S. A2S has  policies of insurance  and bonds of the type and
in amounts customarily carried by persons conducting businesses or owning assets
similar to those of A2S.  There is no material  claim  pending under any of such
policies or bonds as to which coverage has been  questioned,  denied or disputed
by the  underwriters  of such  policies or bonds.  All  premiums due and payable
under all such  policies  and bonds  have  been  paid and A2S are  otherwise  in
compliance  with the terms of such  policies and bonds.  A2S has no knowledge of
any threatened termination of, or material premium increase with respect to, any
of such policies.

                  3.24.  Compliance  With Laws. A2S has complied with, is not in
violation of and has not received any notices of violation  with respect to, any
federal state,  local or foreign statute,  law or regulation with respect to the
conduct of its business,  or the ownership or operation of its business,  except
for such violations or failures to comply as could not be reasonably expected to
have a Material Adverse Effect on A2S.

                                       35
<PAGE>



                  3.25.  Brokers' and Finders' Fees.  A2S has not incurred,  nor
will it incur,  directly or indirectly,  any liability for brokerage or finders'
fees or agents'  commissions or investment  bankers' fees or any similar charges
in connection with this Agreement or any transaction contemplated hereby.

                  3.26. Ownership of Shares and Options.  Except as set forth in
the  A2S  Disclosure   Schedule,   each  A2S  Shareholder  owns  of  record  and
beneficially the number of shares of A2S Common Stock,  indicated  opposite such
A2S Shareholder's  name in Schedule 1.7 hereto,  as applicable,  with full right
and authority to sell or exchange, as applicable, such securities hereunder, and
upon delivery of such shares  hereunder,  EMCON will receive good title thereto,
free and clear of all mortgages,  pledges or security  interests and not subject
to any agreements or understandings among any Persons with respect to the voting
or transfer of such  securities  other than those  arising  under  agreements to
which EMCON is a party.

                  3.27. Execution,  Delivery and Enforceability of Agreement; No
Violation.  This  Agreement has been duly executed and delivered by or on behalf
of each  A2S  Shareholder,  and at the  Closing  any  other  documents  required
hereunder to be executed and  delivered by or on behalf of each A2S  Shareholder
will have been duly  executed and  delivered.  This  Agreement  constitutes  the
legal, valid and binding obligation of each A2S Shareholder, enforceable against
such A2S Shareholder in accordance with its terms,  except as enforcement may be
limited  by  applicable  bankruptcy,  insolvency,   reorganization,   fraudulent
conveyance,  moratorium or other laws affecting creditor's rights generally. Any
other agreements or documents required hereunder to be executed and delivered by
each A2S  Shareholder at Closing will  constitute  the legal,  valid and binding
agreements of each A2S Shareholder executing the same,  enforceable against such
A2S Shareholder in accordance with their respective terms, except as enforcement
may be limited by applicable bankruptcy, insolvency, reorganization,  fraudulent
conveyance,  moratorium or other laws  affecting  creditor's  rights  generally.
Neither the execution of this Agreement nor the consummation of the transactions
contemplated  by each A2S  Shareholder  will  violate,  or  constitute a default
under,  or permit the  acceleration of maturity of, except to the extent waived,
and indentures,  mortgages,  promissory notes,  contracts or agreements to which
such A2S  Shareholder  is a party or by which such A2S  Shareholder  or such A2S
Shareholder's properties are bound.

                  3.28.  Information  Supplied.  To the  Knowledge  of each  A2S
Shareholder,  neither this  Agreement,  the A2S  Financial  Statements,  the A2S
Disclosure  Schedule,  the Exhibits  attached to this  Agreement,  nor any other
certificate  or  document  furnished  or to be  furnished  by  A2S  or  the  A2S
Shareholders  pursuant to the terms of this Agreement,  contains or will contain
any untrue  statement of a material fact known to the A2S  Shareholders  or A2S,
respectively,  or omits or will omit to state a material fact  necessary to make
the  statements  contained in such  information  not  misleading in light of the
circumstances under which such statements were made.

                  3.29.  Residence  and  Domicile.  Each  A2S  Shareholder  is a
resident of, and  domiciled in, the State  indicated on Schedule 1.7 hereto,  as
applicable, as being the residence of such A2S Shareholder.

                  3.30. Brokers or Finders. Neither the A2S Shareholders nor any
of such A2S  Shareholders'  agents have  incurred any  obligation  or liability,
contingent or otherwise,  for brokerage or finders' fees or agents'  commissions
or other similar payment in connection  with this Agreement or the  transactions
contemplated hereby.

                                       36
<PAGE>



                  3.31.  Representations  Complete. To A2S's knowledge,  none of
the  representations  or  warranties  made by A2S herein or in any  Schedule  or
Exhibit hereto,  including the A2S Disclosure Schedule, or certificate furnished
by A2S pursuant to this  Agreement or any written  statement  furnished to EMCON
pursuant hereto or in connection with the transactions contemplated hereby, when
all such documents are read together in their entirety, contain, or will contain
at the Effective Time any untrue  statement of a material fact, or omits or will
omit at the Effective Time to state any material fact necessary in order to make
the statements  contained herein or therein,  in the light of the  circumstances
under which made, not misleading;  provided,  however, that for purposes of this
representation,   any  document   attached  hereto  that  provides   information
inconsistent  with or in addition to any other  written  statement  furnished to
EMCON in connection with the transaction contemplated hereby, shall be deemed to
supersede  any other  document  or  written  statement  furnished  to EMCON with
respect to such inconsistent or additional information.

         4. Representations and Warrantees of EMCON and Sub. Except as disclosed
in a document of even date  herewith and  delivered by EMCON to A2S prior to the
execution and delivery of this  Agreement  and referring to the  representations
and  warranties in this  Agreement (the "EMCON  Disclosure  Schedule"),  each of
EMCON and Sub represents and warrants to A2S as follows:

                  4.1.Organization, Standing and Power. Each of EMCON and Sub is
a corporation  duly organized,  validly  existing and in good standing under the
laws of its jurisdiction of  organization.  EMCON has the corporate power to own
its  properties  and to carry on its  business  as now  being  conducted  and as
proposed to be  conducted  and is duly  qualified  to do business and is in good
standing in each  jurisdiction  in which the failure to be so  qualified  and in
good standing  would have a Material  Adverse  Effect on EMCON.  EMCON is not in
violation of any of the provisions of its Articles of Incorporation or Bylaws or
equivalent organizational documents.

                  4.2. Authority. EMCON and Sub each has all requisite corporate
power  and  authority  to  enter  into  this  Agreement  and to  consummate  the
transactions  contemplated  hereby. The execution and delivery of this Agreement
and the  consummation  of the  transactions  contemplated  hereby have been duly
authorized by all necessary  corporate action on the part of EMCON and Sub. This
Agreement has been duly executed and delivered by EMCON and Sub and  constitutes
the valid and binding obligation of EMCON and Sub. The execution and delivery of
this  Agreement do not and the  consummation  of the  transactions  contemplated
hereby will not conflict  with,  or result in any violation of, or default under
(with or without  notice or lapse of time, or both),  or give rise to a right of
termination,  cancellation or acceleration of any material obligation or loss of
a material  benefit under (i) any provision of the Articles of  Incorporation or
Bylaws of EMCON or any of its  subsidiaries,  as amended,  or (ii) any  material
mortgage,  indenture,  lease,  contract or other agreement or instrument permit,
concession,   franchise,   license,   judgment,  order,  decree,  statute,  law,
ordinance,  rule or regulation applicable to EMCON or any of its subsidiaries or
their properties or assets.  No consent  approval,  order or authorization of or
registration,  declaration or filing with, any Governmental  Entity, is required
by or with respect to EMCON or any of its  subsidiaries  in connection  with the
execution and delivery of this Agreement by EMCON or the  consummation  by EMCON
of the  transactions  contemplated  hereby,  except  for (i) the  filing  of the
Certificate of Merger,  together with the required  officers'  certificates,  as
provided  in  Section  0, (ii) the  filing of a Form D with the  Securities  and
Exchange  Commission  in  accordance  with  Regulation D following the Effective
Time, (iii) the filing of a Form 8-K with the Securities and Exchange Commission
("SEC") and National Association of

                                       37
<PAGE>


Securities  Dealers ("NASD")  within 15 days  after  the  Closing Date, (iv) any
filings  as may be  required  under  applicable  state  securities  laws and the
securities  laws of any  foreign  country,  (v) such  filings as may be required
under HSR,  (vi) the filing with the Nasdaq  National  Market of a  Notification
Form for Listing of Additional Shares with respect to the shares of EMCON Common
Stock issuable upon conversion of the A2S Common Stock in the Merger,  and (vii)
such other consents, authorizations, filings, approvals and registrations which,
if not obtained or made,  would not have a Material  Adverse Effect on EMCON and
would  not  prevent,   materially   alter  or  delay  any  of  the  transactions
contemplated by this Agreement.

                  4.3. SEC Documents:  Financial Statements. EMCON has furnished
to  A2S a true  and  complete  copy  of  each  statement,  report,  registration
statement  (with the prospectus in the form filed pursuant to Rule 424(b) of the
Securities Act), definitive proxy statement, and other filing filed with the SEC
by EMCON since December 31, 1997, and, prior to the Effective  Time,  EMCON will
have  furnished A2S with true and complete  copies of any  additional  documents
filed  with the SEC by EMCON  prior to the  Effective  Time  (collectively,  the
"EMCON  SEC  Documents").  In  addition,  EMCON  has made  available  to A2S all
exhibits  to the EMCON SEC  Documents  filed  prior to the date  hereof and will
promptly  make  available  to A2S  all  exhibits  to any  additional  EMCON  SEC
Documents filed prior to the Effective Time. All documents  required to be filed
as  exhibits to the EMCON SEC  Documents  have been so filed,  and all  material
contracts so filed as exhibits  are in full force and effect  except those which
have expired in  accordance  with their terms,  and neither EMCON nor any of its
subsidiaries is in default thereunder.  As of their respective filing dates, the
EMCON SEC Documents  complied in all material  respects with the requirements of
the  Securities  Exchange Act of 1934, as amended (the  "Exchange  Act") and the
Securities  Act  and  none of the  EMCON  SEC  Documents  contained  any  untrue
statement of a material  fact or omitted to state a material fact required to be
stated therein or necessary to make the statements made therein, in light of the
circumstances  in which they were  made,  not  misleading,  except to the extent
corrected by a  subsequently  filed EMCON SEC Document prior to the date hereof.
The financial statements of EMCON, including the notes thereto,  included in the
EMCON SEC Documents (the "EMCON Financial  Statements"),  complied as to form in
all material  respects  with  applicable  accounting  requirements  and with the
published  rules and  regulations  of the SEC with  respect  thereto as of their
respective  dates, and have been prepared in accordance with generally  accepted
accounting  principles  applied on a basis  consistent  throughout  the  periods
indicated  and  consistent  with each other  (except as may be  indicated in the
notes  thereto or, in the case of  unaudited  statements  included in  Quarterly
Reports  on Form  10-Qs,  as  permitted  by Form  10-Q of the  SEC).  The  EMCON
Financial  Statements  fairly present the consolidated  financial  condition and
operating  results  of EMCON and its  subsidiaries  at the dates and  during the
periods  indicated  therein (subject,  in the case of unaudited  statements,  to
normal,  recurring  yearend  adjustments).  There  has been no  change  in EMCON
accounting  policies  except as  described  in the notes to the EMCON  Financial
Statements.

                  4.4. Absence of Certain Changes.  Since December 31, 1997 (the
"EMCON  Balance Sheet  Date"),  EMCON has conducted its business in the ordinary
course consistent with past practice and there has not occurred: (i) any change,
event or condition  (whether or not covered by insurance)  that has resulted in,
or might  reasonably  be  expected  to result in, a Material  Adverse  Effect to
EMCON; (ii) any acquisition,  sale or transfer of any material asset of EMCON or
any of its  subsidiaries  other  than in the  ordinary  course of  business  and
consistent  with past  practice;  (iii)  any  change in  accounting  methods  or
practices  (including any change in  depreciation  or  amortization  policies or
rates)  by EMCON or any  revaluation  by  EMCON of any of its  assets;  (iv) any
declaration,  setting aside, or payment of a dividend or other distribution with
respect to

                                       38
<PAGE>


the  shares  of  EMCON,  or  any  direct or  indirect  redemption,  purchase  or
other  acquisition  by EMCON of any of its  shares  of  capital  stock;  (v) any
material  contract  entered into by EMCON,  other than in the ordinary course of
business and as provided to A2S or any material  amendment or termination of, or
default under, any material contract to which EMCON is a party or by which it is
bound;  (vi) any  amendment or change to EMCON's  Articles of  Incorporation  or
Bylaws;  or  (vii)  any  negotiation  or  agreement  by  EMCON  or  any  of  its
subsidiaries  to do any of the things  described  in the  preceding  clauses (i)
through (vi) (other than negotiations with A2S and its representatives regarding
the transactions contemplated by this Agreement).

                  4.5. Absence of Undisclosed Liabilities. EMCON has no material
obligations  or  liabilities  of any  nature  (matured  or  unmatured,  fixed or
contingent)  other than (i) those set forth or  adequately  provided  for in the
Balance  Sheet  included  in EMCON's  Annual  Report on Form 10-K for the period
ended December 31, 1997 (the "EMCON Balance Sheet"),  (ii) those incurred in the
ordinary  course  of  business  and not  required  to be set  forth in the EMCON
Balance Sheet under generally accepted  accounting  principles,  and (iii) those
incurred in the ordinary  course of business  since the EMCON Balance Sheet Date
and consistent with past practice.

                  4.6.  Litigation.  There is no private or governmental action,
suit, proceeding, claim, arbitration or investigation pending before any agency,
court or tribunal,  foreign or domestic, or, to the knowledge of EMCON or any of
its subsidiaries,  threatened against EMCON or any of its subsidiaries or any of
their respective properties or any of their respective officers or directors (in
their  capacities  as  such)  that,  individually  or in  the  aggregate,  could
reasonably be expected to have a Material  Adverse Effect on EMCON.  There is no
judgment,  decree or order against EMCON or any of its  subsidiaries  or, to the
knowledge of EMCON or any of its subsidiaries, any of their respective directors
or  officers  (in their  capacities  as such) that  could  prevent,  enjoin,  or
materially  alter  or  delay  any  of  the  transactions  contemplated  by  this
Agreement,  or that could  reasonably  be  expected  to have a Material  Adverse
Effect on EMCON.

                  4.7. Governmental  Authorization.  Except where the failure to
obtain or have any of such EMCON Authorizations could not reasonably be expected
to have a Material  Adverse Effect on EMCON,  EMCON and each of its subsidiaries
have  obtained  each  federal,  state,  county,  local or  foreign  governmental
consent, license, permit, grant, or other authorization of a Governmental Entity
(i)  pursuant to which EMCON or any of its  subsidiaries  currently  operates or
holds any  interest in any of its  properties  or (ii) that is required  for the
operation of EMCON's or any of its subsidiaries'  business or the holding of any
such interest ((i) and (ii) herein collectively called "EMCON  Authorizations"),
and all of such EMCON Authorizations are in full force and effect.

                  4.8.  Broker's and Finders' Fees. EMCON has not incurred,  nor
will it incur,  directly or indirectly,  any liability for brokerage or finders'
fees or agents'  commissions or investment  bankers' fees or any similar charges
in connection with this Agreement or any transaction contemplated hereby.

                  4.9. Compliance With Laws. Each of EMCON and Sub have complied
with,  are not in  violation  of and have not  received any notices of violation
with respect to, any federal state, local or foreign statute,  law or regulation
with respect to the conduct of its  business,  or the  ownership or operation of
its business,  except for such  violations or failures to comply as could not be
reasonably expected to have a Material Adverse Effect on EMCON or SUB.

                                       39
<PAGE>


                  4.10. Brokers' and Finders' Fees. EMCON has not incurred,  nor
will it incur,  directly or indirectly,  any liability for brokerage or finders'
fees or agents'  commissions or investment  bankers' fees or any similar charges
in connection with this Agreement or any transaction contemplated hereby.

                  4.11. Execution,  Delivery and Enforceability of Agreement; No
Violation.  This  Agreement has been duly executed and delivered by or on behalf
of each of EMCON  and Sub,  and at the  Closing  any  other  documents  required
hereunder to be executed and  delivered by or on behalf of each of EMCON and Sub
will have been duly  executed and  delivered.  This  Agreement  constitutes  the
legal,  valid  and  binding  obligation  of each of EMCON  and Sub,  enforceable
against  each  of  EMCON  and  Sub in  accordance  with  its  terms,  except  as
enforcement may be limited by applicable bankruptcy, insolvency, reorganization,
fraudulent  conveyance,  moratorium or other laws  affecting  creditor's  rights
generally.  Any other agreements or documents  required hereunder to be executed
and  delivered  by each of EMCON and Sub at Closing will  constitute  the legal,
valid and binding  agreements of EMCON and Sub  executing the same,  enforceable
against each of EMCON and Sub in accordance with their respective terms,  except
as   enforcement   may  be  limited  by   applicable   bankruptcy,   insolvency,
reorganization,  fraudulent  conveyance,  moratorium  or  other  laws  affecting
creditor's  rights  generally.  Neither the execution of this  Agreement nor the
consummation  of the  transactions  contemplated  by each of EMCON  and Sub will
violate,  or constitute a default under, or permit the  acceleration of maturity
of, except to the extent waived,  and indentures,  mortgages,  promissory notes,
contracts  or  agreements  to which each of EMCON and Sub is a party or by which
EMCON and Sub or EMCON's and Sub's properties are bound.

                  4.12.  `Information  Supplied.  To the  Knowledge of EMCON and
Sub, neither this Agreement,  the Exhibits  attached to this Agreement,  nor any
other certificate or document  furnished or to be furnished by each of EMCON and
Sub pursuant to the terms of this Agreement, contains or will contain any untrue
statement  of a material  fact  known to EMCON or Sub,  or omits or will omit to
state a  material  fact  necessary  to make  the  statements  contained  in such
information  not  misleading  in light of the  circumstances  under  which  such
statements were made.

                  4.13.  Representations Complete. To EMCON's knowledge, none of
the  representations  or  warranties  made by EMCON  herein  or in any  Schedule
hereto,  including the EMCON Disclosure  Schedule,  or certificate  furnished by
EMCON pursuant to this  Agreement,  or the EMCON SEC  Documents,  or any written
statement   furnished  to  A2S  pursuant   hereto  or  in  connection  with  the
transactions  contemplated  hereby, when all such documents are read together in
their  entirety,  contains  or will  contain  at the  Effective  Time any untrue
statement  of a  material  fact or omits or will omit at the  Effective  Time to
state any  material  fact  necessary in order to make the  statements  contained
herein or therein,  in the light of the  circumstances  under  which  made,  not
misleading;  provided,  however,  that for purposes of this representation,  any
document  attached  hereto that  provides  information  inconsistent  with or in
addition to any other written statement  furnished to A2S in connection with the
transactions  contemplated  hereby,  shall be  deemed  to  supersede  any  other
document or written statement furnished to A2S with respect to such inconsistent
or additional information.

         5.       Conduct Prior To The Effective Time.

                  5.1.  Conduct of Business of A2S and EMCON.  During the period
from  the  date of this  Agreement  and  continuing  until  the  earlier  of the
termination  of this  Agreement  or the  Effective  Time,  each of A2S and EMCON
agrees  (except to the extent  expressly  contemplated  by this  Agreement or as
consented to in writing by the other), to carry on its and its subsidiaries'

                                       40
<PAGE>


business  in  the  usual regular and ordinary course  in  substantially the same
manner as  heretofore  conducted;  to pay and to cause its  subsidiaries  to pay
debts and Taxes when due subject (i) to good faith  disputes  over such debts or
Taxes and (ii) in the case of Taxes of A2S, to EMCON's  consent to the filing of
material Tax Returns if  applicable;  to pay or perform other  obligations  when
due, and to use all reasonable  efforts to preserve intact its present  business
organizations,  keep available the services of its and its subsidiaries' present
officers and key employees and preserve its and its subsidiaries'  relationships
with customers, suppliers, distributors, licensors, licensees, and others having
business  dealings  with it or its  subsidiaries,  to the end  that  its and its
subsidiaries'  goodwill  and  ongoing  businesses  shall  be  unimpaired  at the
Effective Time. Each of A2S and EMCON agrees to promptly notify the other of (x)
any event or occurrence not in the ordinary  course of its or its  subsidiaries'
business,  and of any event which could have a Material  Adverse  Effect and (y)
any material change in its  capitalization as set forth in Sections 3.5. Without
limiting the foregoing,  except as expressly  contemplated  by this Agreement or
the A2S Disclosure  Schedule or the EMCON Disclosure  Schedule,  neither A2S nor
EMCON,  respectively,  shall do, cause or permit any of the following, or allow,
cause or  permit  any of its  subsidiaries  to do,  cause or  permit  any of the
following, without the prior written consent of the other:

                           (a)      Charter  Documents.   Cause or permit any  
amendments  to  its  Articles  of Incorporation or Bylaws;

                           (b)      Dividends;  Changes  in  Capital  Stock.  
Except  for (i) the  purchase of  the  Cuerdon  Promissory Note and the related
release of the 10,000  shares of A2S common stock  delivered as security for the
Cuerdon  Promissory  Note,  or (ii) as  otherwise  approved in writing by EMCON,
declare or pay any  dividends  on or make any other  distributions  (whether  in
cash,  stock or  property)  in respect of any of its  capital  stock,  or split,
combine  or  reclassify  any of its  capital  stock or issue  or  authorize  the
issuance of any other  securities  in respect of, in lieu of or in  substitution
for shares of its capital stock, or repurchase or otherwise acquire, directly or
indirectly,  any shares of its  capital  stock  except  from  former  employees,
directors  and  consultants  in  accordance  with  agreements  providing for the
repurchase of shares in connection  with any termination of service to it or its
subsidiaries;

                           (c)    Other. Take, or agree in writing or otherwise
to  take,  any  of  the  actions  described  in  Sections  5.1 (a) through (b)
above, or any action which would cause a material breach of its  representations
or  warranties  contained  in this  Agreement  or  prevent  it  from  materially
performing or cause it not to materially perform its covenants hereunder.

                  5.2.  Conduct of Business  of A2S.  During the period from the
date of this  Agreement and continuing  until the earlier of the  termination of
this Agreement or the Effective Time,  except as expressly  contemplated by this
Agreement or the A2S Disclosure Schedule,  A2S shall not do, cause or permit any
of the following, without the prior written consent of EMCON:

                           (a)      Material Contracts.  Enter into any material
contract  or commitment,  or violate, amend   or otherwise  modify or waive any
of the terms of any of its material contracts, other than in the ordinary course
of business consistent with past practice;

                           (b)      Issuance of  Securities.  Issue, deliver or 
sell or  authorize  or propose the  issuance, delivery  or  sale of, or purchase
or  propose  the  purchase  of, any shares of its  capital  stock or  securities
convertible into, or subscriptions, rights, warrants or options to acquire, or

                                       41
<PAGE>


other  agreements  or commitments of any character obligating it to issue any
such shares or other convertible securities;

                           (c)      Intellectual  Property.  Transfer  to any  
person or entity  any  rights to its Intellectual Property other than in the 
ordinary course of business consistent with past practice;

                           (d)      Exclusive  Rights.  Enter into or amend any
agreements  pursuant  to  which any  other party is granted exclusive marketing
or  other  exclusive  rights  of any type or scope  with  respect  to any of its
products or technology;

                           (e)      Dispositions.  Sell, lease,  license or 
otherwise  dispose of or  encumber any  of its  properties or assets  which  are
material  individually  or in the  aggregate,  to its  business,  except  in the
ordinary course of business consistent with past practice;

                           (f)      Indebtedness.  Incur any  indebtedness for 
borrowed  money  or  guarantee  any such indebtedness or issue or sell any debt 
securities or guarantee any debt securities of others;

                           (g)      Agreements.  Enter into, terminate or amend,
in  a  manner  which  will  adversely  affect  the  business  of A2S (i) any
agreement  involving  an  obligation  to pay or the right to receive  $10,000 or
more, (ii) any agreement relating to the license,  transfer or other disposition
or acquisition of  intellectual  property rights or rights to market or sell A2S
products,  or (iii) any other  agreement  which is material  to the  business or
prospects of A2S.

                            (h)     Payment of  Obligations.  Pay, discharge or 
satisfy  in  an  amount in  excess of  $10,000  in  the  aggregate,  any  claim,
liability or obligation (absolute,  accrued, asserted or unasserted,  contingent
or otherwise) arising other than in the ordinary course of business,  other than
the payment,  discharge or  satisfaction  of  liabilities  reflected or reserved
against in the A2S Financial Statements;

                           (i)      Capital  Expenditures.  Make any capital  
expenditures,  capital  additions  or  capital  improvements  except  in  the
ordinary course of business and consistent with past practice;

                           (j)      Insurance.  Materially  reduce the amount of
any  material  insurance  coverage provided by existing insurance policies;

                           (k)      Termination  or Waiver.  Terminate or waive 
any right of  substantial  value, other than in the ordinary course of business;

                           (l)      Employee Benefit Plans;  New  Hires; Pay 
Increases.  Adopt or  amend  any  employee  benefit or stock purchase or option
plan,  or hire any new employee,  pay any special bonus or special  remuneration
(except  payments made pursuant to written  agreements  outstanding  on the date
hereof),  or increase the salaries or wage rates of its employees  except in the
ordinary course of business in accordance with its standard past practice;

                           (m)      Severance Arrangements.  Grant any severance
or  termination  pay (i) to any  director  or  officer  or (ii) to any  other
employee except (A) payments made pursuant to written agreements  outstanding on
the date hereof or (B) grants which are made in the ordinary  course of business
in accordance with its standard past practice;

                                       42
<PAGE>



                           (n)      Lawsuits.  Commence a lawsuit  other than  
(i)  for  the  routine  collection  of bills,  (ii) in  such cases where it in
good faith determines that failure to commence suit would result in the material
impairment of a valuable aspect of its business,  provided that it consults with
EMCON  prior  to the  filing  of such a suit,  or  (iii)  for a  breach  of this
Agreement;
                           (o)      Acquisitions.  Acquire or agree to acquire 
by  merging  or consolidating  with, or by  purchasing a substantial portion of
the  assets  of,  or by any  other  manner,  any  business  or any  corporation,
partnership,  association or other business  organization or division thereof or
otherwise acquire or agree to acquire any assets which are material individually
or in the aggregate, to its business;

                           (p)      Taxes.  Other than in the  ordinary  course 
of  business,  make  or change  any  material  election  in  respect of Taxes,
adopt or change any accounting method in respect of Taxes, file any material Tax
Return or any  amendment  to a  material  Tax  Return,  enter  into any  closing
agreement,  settle any  material  claim or  assessment  in respect of Taxes,  or
consent to any extension or waiver of the  limitation  period  applicable to any
material claim or assessment in respect of Taxes;

                           (q)      Revaluation.  Revalue any of its assets,  
including without  limitation writing down the value of  inventory  or writing  
off notes or accounts  receivable  other than in the  ordinary  course of
business; or

                           (r)      Other.  Take or agree in  writing  or  
otherwise  to  take, any of the actions described in Sections 5.2 (a) through
(q)  above,   or  any  action  which  would  cause  a  material  breach  of  its
representations  or  warranties  contained in this  Agreement or prevent it from
materially  performing  or  cause it not to  materially  perform  its  covenants
hereunder.

         6.       Additional Agreements.

                  6.1      Payment of Additional Merger Consideration.

                           (a)      In addition to the Merger Consideration to 
be  delivered  the A2S  Shareholders at the Closing  pursuant to Sections 1.6
and 1.7 hereof,  the A2S  Shareholders  will be  eligible to earn as  additional
consideration  for the Merger,  an aggregate  earnout amount up to Three Hundred
Thousand  Dollars  ($300,000)  in the form of cash and EMCON  Common  Stock (the
"Additional Consideration"),  subject to the Surviving Corporation achieving the
milestones set forth below. The form of the aggregate  Additional  Consideration
to be paid to the A2S Shareholders (pro rata based on the total number of shares
of A2S  Capital  Stock  held by each A2S  Shareholder  immediately  prior to the
Effective  Time)  will be 50% in cash and 50% in  shares of  unregistered  EMCON
Common  Stock  valued at the closing  price of EMCON Common Stock as reported on
the Nasdaq  National  Market on the first  business day  following the end of an
Earnings Period (as defined below).

                           (b)      In the event that the Surviving Corporation 
achieves  the  pretax  income  milestones (the "Income Milestones"), subject to
the  conditions set forth below,  during the two twelve month periods  following
the Effective Time (the "Earnings  Period"),  EMCON agrees to deliver to the A2S
Shareholders the aggregate earn-out payments (the "Earnout  Payments") set forth
opposite each Earnings Period, all as set forth below.

                                       43
<PAGE>






           Earnings Period            Income Milestone         Earnout Payments


             Months 1-12                $500,000                  $150,000
             Months 13-24               $600,000                  $150,000

         The  calculation  of the  Surviving  Corporation's  pretax  income  for
purposes  of this  Section  7.1 will be based on the  application  of  Generally
Accepted  Accounting  Principles,  consistently  applied,  including  the use of
accrual  accounting.  For purposes of calculating the Income  Milestones,  EMCON
shall  not  allocate  any  portion  of its  general  corporate  overhead  to the
Surviving Corporation. Notwithstanding the foregoing, to the extent EMCON incurs
expenses (e.g.  insurance,  legal,  outside  accounting,  etc.) directly for the
benefit of the  Surviving  Corporation,  or  otherwise  provides  administrative
services for the benefit of the Surviving  Corporation,  the actual cost of such
items (i.e.,  without any markup) shall be charged to the Surviving  Corporation
for purposes of such calculation.

                  6.2     Operation and Management of the Surviving Corporation.

                           (a)      The parties to this Agreement agree that, 
unless  subsequently  changed  with  the approval of the Board of Directors of
the  Surviving  Corporation,  the  Surviving  Corporation  will  retain the name
"Advanced  Analytical  Solutions,  Inc." While name  retention is primarily  for
client relation purposes, it symbolically  signifies the reasonable  operational
autonomy of the Surviving Corporation desired by the parties.

                           (b)      Immediately following the Effective Time, 
William  J.  Hengemihle   ("Hengemihle")  and  Christopher  M.  Wittenbrink
("Wittenbrink") shall be elected to the offices of President and Vice President,
respectively,  of the Surviving Corporation.  Hengemihle will report directly to
Gene  Herson  in his role as the  President  of  EMCON's  Professional  Services
Division.

                           (c)      Immediately  following the Effective  Time,
the  Board  of  Directors  of  Surviving   Corporation   shall  consist  of
Hengemihle, Wittenbrink, Gary McEntee and Michael Momboisse.

                           (d)      The parties hereto agree that the Surviving
Corporation  will  have  reasonable  autonomy  concerning  its  business affairs
as a manner of principle.  However,  the Surviving  Corporation accepts and will
abide by EMCON's business and personnel policies.  In this regard, the Surviving
Corporation  agrees to at least meet the minimum  standards  established for all
EMCON  operations with respect to EMCON's  policies  regarding human  resources,
employee  benefits,  insurance  coverage,  accounting  policies and  procedures,
contract administration and risk management.

                           (e)      EMCON will assist the Surviving Corporation 
in  setting  up its accounting  systems to comply  with EMCON's standards.  This
shall include  accrual  accounting,  similar charts of accounts and  integration
with EMCON's Sacramento Accounting Center.

                           (f)     Following the Closing, EMCON may, at its sole
option,  pay off all outstanding long  term  debt of the  Surviving Corporation.

                                       44
<PAGE>


                  6.3. Future Grant of Options to Purchase Common Stock of EMCON
EMCON  agrees to reserve  options to purchase  an  aggregate  of Fifty  Thousand
(50,000) shares of EMCON Common Stock (the "Options") for issuance to Hengemihle
and Wittenbrink and other key managers of the Surviving  Corporation  Hengemihle
and  Wittenbrink  deem  appropriate,  if any. The parties hereto intend that the
Options will be incentive  stock  options  granted  pursuant to EMCON's new 1998
Stock  Option  Plan  (the  "Option  Plan").  Such  treatment  however,  will  be
conditioned upon the formal approval of the Option Plan by EMCON's  shareholders
at the annual meeting of shareholders to be held May 28, 1998 (the  "Shareholder
Meeting").  In the event the  shareholders  do not approve the Option Plan,  the
Options will be granted  pursuant to a  nonqualified  plan and will,  therefore,
qualify as nonqualified stock options. In any event, the Options granted will be
granted  subject to the standard  terms and  conditions of the EMCON's  existing
stock option plan and agreements which provides,  among other things, for a five
year term and vesting in equal  installments over a four year period. No Options
will be granted prior to the date of the Shareholder Meeting. The exercise price
of the  Options  will be set at the  closing  price  of  EMCON  Common  Stock as
reported on the Nasdaq National Market on the date of such grant.

                  6.4.   Participation  in   Pay-for-Performance   Program.  The
executive  officers and continuing  managers of Surviving  Corporation  shall be
eligible to participate in EMCON's Pay-for-Performance program (the "Performance
Program").  For the twelve month period immediately following the Effective Time
(the "First  Performance  Period"),  the amount  accrued  under the  Performance
Program shall equal 50% of all pretax  profits of the Surviving  Corporation  in
excess of $500,000.  For the twelve month period following the First Performance
Period, the amount accrued under the Performance  Program shall equal 50% of all
pretax profits of the Surviving Corporation in excess of $600,000. Allocation of
the respective bonus pools among the Surviving Corporation employees shall be at
the discretion of the executive officers of the Surviving  Corporation,  subject
only to general  oversight and written consent of the Compensation  Committee of
the Board of Directors of EMCON.

                    At the  Closing,  EMCON shall loan Timothy M. Keaten the sum
of Two Hundred Twenty-Five  Thousand Dollars ($225,000) pursuant to the terms of
a three year full  recourse  promissory  note (the "Note") and pledge  agreement
("Pledge  Agreement"),  in the form attached hereto as Exhibit E, secured by the
EMCON  Common  Stock  to be  issued  to  Mr.  Keaten  as an A2S  Shareholder  in
connection  with the Merger as set forth in Schedule 1.7 hereto.  The Note shall
be due and  payable in full after three  years and shall bear  interest  payable
quarterly  at the rate of 8% per  annum,  calculated  on the  basis of a 360 day
year.

                  6.6.     Access to Information.

                           (a)      A2S shall afford EMCON and its accountants,
counsel  and  other representatives,  reasonable  access during normal business
hours  during  the  period  prior  to the  Effective  Time to (i)  all of  A2S's
properties,  books,  contracts,  commitments  and  records,  and (ii) all  other
information  concerning  the business,  properties and personnel of A2S as EMCON
may  reasonably  request.  A2S agrees to  provide to EMCON and its  accountants,
counsel  and other  representatives  copies  of  internal  financial  statements
promptly upon request.  EMCON shall afford A2S and its accountants,  counsel and
other representatives, reasonable access during normal business hours during the
period prior to the Effective  Time to (i) all of EMCON's and its  subsidiaries'
properties,  books,  contracts,  commitments  and  records,  and (ii) all  other
information  concerning the business,  properties and personnel of EMCON and its
subsidiaries as A2S may

                                       45
<PAGE>

reasonably  request.  EMCON  agrees  to  provide to  A2S  and its  accountants,
counsel  and other  representatives  copies  of  internal  financial  statements
promptly upon request.

                           (b)      Subject to compliance with  applicable law,
from  the  date  hereof until  the Effective  Time, each of EMCON and A2S shall
confer on a regular and frequent basis with one or more  representatives  of the
other party to report operational  matters of materiality and the general status
of ongoing operations.

                           (c)      No information or knowledge obtained in any
investigation  pursuant to  this  Section  6.6 shall  affect or  be deemed to
modify any  representation or warranty contained herein or the conditions to the
obligations of the parties to consummate the Merger.

                  6.7.  Confidentiality.  The parties acknowledge that EMCON and
A2S have previously  executed a non-disclosure  agreement dated May 2, 1997 (the
"Non-Disclosure   Agreement"),   which   Non-Disclosure   Agreement   is  hereby
incorporated  herein by reference and shall continue in full force and effect in
accordance with its terms.

                  6.8. Public  Disclosure.  Unless  otherwise  permitted by this
Agreement,  EMCON and A2S shall consult with each other before issuing any press
release or otherwise  making any public statement or making any other public (or
non-confidential)  disclosure  (whether  or  not  in  response  to  an  inquiry)
regarding the terms of this Agreement and the transactions  contemplated hereby,
and neither  shall issue any such press  release or make any such  statement  or
disclosure  without the prior approval of the other (which approval shall not be
unreasonably  withheld),  except  as may be  required  by law or by  obligations
pursuant to any listing agreement with any national  securities exchange or with
the NASD.

                  6.9.  Consents;  Cooperation.  Each of  EMCON  and  A2S  shall
promptly apply for or otherwise seek, and use reasonable best efforts to obtain,
all consents and approvals required to be obtained by it for the consummation of
the Merger,  including  those required under HSR, and shall use reasonable  best
efforts to obtain all necessary consents, waivers and approvals under any of its
material  contracts in connection with the Merger for the assignment  thereof or
otherwise.

                  6.10. Legal Requirements.  Each of EMCON and A2S will take all
reasonable  actions  necessary to comply  promptly  with all legal  requirements
which  may  be  imposed  on  them  with  respect  to  the  consummation  of  the
transactions contemplated by this Agreement and will promptly cooperate with and
furnish  information to any party hereto  necessary in connection  with any such
requirements  imposed upon such other party in connection with the  consummation
of the transactions  contemplated by this Agreement and will take all reasonable
actions necessary to obtain (and will cooperate with the other parties hereto in
obtaining) any consent, approval, order or authorization of or any registration,
declaration or filing with, any Governmental Entity or other person, required to
be obtained or made in connection with the taking of any action  contemplated by
this Agreement.

                  6.11.  Blue Sky Laws.  EMCON  shall  take such steps as may be
necessary to comply with the securities  and blue sky laws of all  jurisdictions
which are  applicable  to the issuance of the EMCON  Common Stock in  connection
with the  Merger.  A2S shall  use its best  efforts  to  assist  EMCON as may be
necessary to comply with the securities  and blue sky laws of all  jurisdictions
which are  applicable in  connection  with the issuance of EMCON Common Stock in
connection with the Merger.

                                       46
<PAGE>



                  6.12.  Nonaccredited  Shareholders.  Prior to the Closing, A2S
shall not take any action,  including  the granting of employee  stock  options,
that  would  cause  the  number  of A2S  shareholders  who are  not  "accredited
investors"  pursuant to Regulation D  promulgated  under the  Securities  Act of
1933, as amended, to increase to more than 35 during the term of this Agreement.

                  6.13.  Listing of Additional  Shares.  Following the Effective
Time,  EMCON shall file with the Nasdaq National Market a Notification  Form for
Listing of  Additional  Shares with  respect to the shares of EMCON Common Stock
issuable upon conversion of the A2S Common Stock in the Merger.

                  6.14.  Expenses.  The  parties  will each pay their own legal,
accounting  and  professional  expenses  ("Expenses")  in  connection  with  the
transactions  contemplated  hereby. In the event the Merger is consummated,  the
Expenses  incurred by A2S and/or its  shareholders  up to an aggregate  total of
$20,000 shall be paid by EMCON.

                  6.15.  Registration  of Shares  Issued in the  Merger.  At the
Closing,  EMCON shall grant to the A2S Shareholders  certain registration rights
set forth in the EMCON Registration  Rights Agreement with respect to the shares
of EMCON Common Stock issued in the Merger.

                  6.16.  Personal  Guarantees.  From and after the Closing Date,
EMCON  agrees to work  diligently  to have each of  William  J.  Hengemihle  and
Timothy M. Keaten released from his obligations and liability under the Personal
Guarantees.  The term  "Personal  Guarantee"  shall mean the personal  financial
guarantees  given by each of  William J.  Hengemihle  and  Timothy M.  Keaten in
connection  with certain debt  obligations  of A2S as set forth on Schedule 6.16
hereto.


         7.       Termination, Amendment and Waiver

                  7.1. Termination. This Agreement may be terminated at any time
prior to the Effective  Time (with  respect to Section  7.1(b)  through  Section
7.1(d), by written notice by the terminating party to the other party):

                           (a)      by the mutual written consent of EMCON and 
A2S;

                           (b)      by either EMCON or A2S if the Merger shall 
not  have  been  consummated by April 11, 1998,  provided,  however,  that  the
right to  terminate  this  Agreement  under  this  Section  7.1 (b) shall not be
available  to any party  whose  failure to  fulfill  any  obligation  under this
Agreement  has been the cause of or  resulted  in the  failure  of the Merger to
occur on or before such date;

                           (c)      by  either  EMCON  or  A2S  if a  court  of
competent  jurisdiction  or  other  Governmental  Entity  shall  have issued  a
nonappealable  final order,  decree or ruling or taken any other action, in each
case  having the  effect of  permanently  restraining,  enjoining  or  otherwise
prohibiting the Merger,  except,  if the party relying on such order,  decree or
ruling  or other  action  has not  complied  with  its  obligations  under  this
Agreement;

                           (d)      by  either  EMCON or A2S, if there has been
a  breach  of  any representation, warranty,  covenant  or agreement on the part
of the other  party set forth in this  Agreement,  which  breach  (i) causes the
conditions set forth in Section 2.2 (a) or (b) (in the case

                                       47
<PAGE>


of  termination  by  EMCON)  or  Section  2.3 (a) or (b)  (in  the  case of
termination  by A2S) not to be  satisfied  and (ii)  shall not have  been  cured
within  ten (10)  business  days  following  receipt by the  breaching  party of
written notice of such breach from the other party

                  7.2.  Effect of  Termination.  In the event of  termination of
this  Agreement  as provided in Section  7.1,  there  shall be no  liability  or
obligation on the part of EMCON, A2S or their respective officers, directors, or
shareholders,  except to the  extent  that  such  termination  results  from the
willful breach by a party of any of its representations, warranties or covenants
set forth in this  Agreement;  provided  that the  provisions of Section 0 shall
remain in full force and effect and survive any termination of this Agreement.

                  7.3.  Amendment  This  Agreement may be amended by the parties
hereto,  by action taken or authorized by their respective  Boards of Directors.
This  Agreement may not be amended  except by an instrument in writing signed on
behalf of each of the parties hereto.

                  7.4.  Extension;  Waiver  At any time  prior to the  Effective
Time,  the parties  hereto,  by action taken or authorized  by their  respective
Boards of Directors, may, to the extent legally allowed, (i) extend the time for
the  performance  of any of the  obligations  or other acts of the other parties
hereto,  (ii)  waive any  inaccuracies  in the  representations  and  warranties
contained  herein or in any document  delivered  pursuant hereto and (iii) waive
compliance  with any of the  agreements  or  conditions  contained  herein.  Any
agreement on the part of a party hereto to any such extension or waiver shall be
valid only if set forth in a written instrument signed on behalf of such party.

         8.       General Provisions.

                  8.1. Notices. All notices and other  communications  hereunder
shall be in writing and shall be deemed duly  delivered if delivered  personally
(upon  receipt),  or three (3) business days after being mailed by registered or
certified mail, postage prepaid (return receipt requested),  or one (1) business
day after it is sent by reputable  nationwide overnight courier service, or upon
transmission,  if sent via  facsimile  (with  confirmation  of  receipt)  to the
parties at the following  address (or at such other address for a party as shall
be specified by like notice):


         (a)      if to EMCON, to:

                  EMCON
                  400 S. El Camino Real, Suite 1200
                  San Mateo, CA  94402
                  Attention:  R. Michael Momboisse, Chief Financial Officer
                  Fax:     (650) 375-0763

                  with a copy to:

                  Gray Cary Ware & Freidenrich LLP
                  400 Hamilton Avenue
                  Palo Alto, CA  94301
                  Attention:  Eric J. Lapp, Esq.
                  Fax:     (650) 328-6561

                                       48
<PAGE>


         (b)      if to A2S, to

                  Advanced Analytical Solutions, Inc.
                  1331 17th Street, Suite 600
                  Denver, CO  80202
                  Attention:  William J. Hengemihle, President
                  Fax:     (303) 295-2692

                  with a copy to:

                  Schlueter & Associates, P.C.
                  1050 Seventeenth Street, Suite 1700
                  Denver, Colorado 80265
                  Attention: Henry F. Schlueter
                  Fax:     (303) 292-3883

         (c)      if to the A2S Shareholders:

                  William J. Hengemihle
                  51 Casselberry Drive
                  Audubon, Pennsylvania 19403

                  Christopher M. Wittenbrink
                  2715 South Pierce Street
                  Denver, Colorado 80227

                  Timothy M. Keaten
                  3048 East Clairton Drive
                  Highlands Ranch, Colorado 80126
                  Fax: (303) 703-0527

                  with a copy to:

                  Schlueter & Associates, P.C.
                  1050 Seventeenth Street, Suite 1700
                  Denver, Colorado 80265
                  Attention: Henry F. Schlueter
                  Fax:     (303) 292-3883

                  8.2.  Definitions.  In this  Agreement  any  reference  to any
event,  change,  condition or effect being "material" with respect to any entity
or group of entities  means any  material  event,  change,  condition  or effect
related to the financial  condition,  properties,  assets (including  intangible
assets),  liabilities,  business,  operations  or results of  operations of such
entity or group of  entities.  In this  Agreement  any  reference to a "Material
Adverse Effect" with respect to any entity or group of entities means any event,
change  or  effect  that  is  materially  adverse  to the  financial  condition,
properties,  assets, liabilities,  business, operations or results of operations
of such entity and its  subsidiaries,  taken as a whole.  In this  Agreement any
reference to a party's  "knowledge"  means such party's actual  knowledge  after
reasonable  inquiry of  officers,  directors  and other  employees of such party
reasonably believed to have knowledge of such matters.

                                       49
<PAGE>


                  8.3.  Counterparts  This  Agreement  may be executed in one or
more  counterparts,  all of which shall be considered one and the same agreement
and shall become  effective  when one or more  counterparts  have been signed by
each of the parties and delivered to the other parties, it being understood that
all parties need not sign the same counterpart.

                  8.4. Entire Agreement; Nonassignability;  Parties in Interest.
This  Agreement  and  the  documents  and  instruments   and  other   agreements
specifically  referred to herein or delivered  pursuant  hereto,  including  the
Exhibits,  the Schedules,  including the A2S  Disclosure  Schedule and the EMCON
Disclosure  Schedule (a) constitute the entire  agreement among the parties with
respect to the subject  matter  hereof and supersede  all prior  agreements  and
understandings,  both  written and oral,  among the parties  with respect to the
subject  matter hereof  except for the  Confidentiality  Agreement,  which shall
continue in full force and effect,  and shall  survive any  termination  of this
Agreement or the Closing,  in accordance with its terms; (b) are not intended to
confer upon any other person any rights or remedies hereunder,  and shall not be
assigned by  operation of law or  otherwise  without the written  consent of the
other party.

                  8.5.  Severability.  In the event that any  provision  of this
Agreement,  or the  application  thereof  becomes or is  declared  by a court of
competent  jurisdiction to be illegal,  void or unenforceable,  the remainder of
this  Agreement  will continue in full force and effect and the  application  of
such  provision to other  persons or  circumstances  will be  interpreted  so as
reasonably to effect the intent of the parties hereto. The parties further agree
to replace such void or  unenforceable  provision of this Agreement with a valid
and  enforceable  provision  that will  achieve,  to the  extent  possible,  the
economic, business and other purposes of such void or unenforceable provision.

                  8.6. Remedies Cumulative. Except as otherwise provided herein,
any and all  remedies  herein  expressly  conferred  upon a party will be deemed
cumulative with and not exclusive of any other remedy  conferred  hereby,  or by
law or equity  upon such  party,  and the  exercise by a party of any one remedy
will not preclude the exercise of any other remedy.

                  8.7.  Governing Law. This  Agreement  shall be governed by and
construed in accordance with the laws of California that might otherwise  govern
under  applicable  principles  of conflicts of law.  Each of the parties  hereto
irrevocably  consents to the exclusive  jurisdiction of any court located within
San Mateo County, State of California,  in connection with any matter based upon
or arising  out of this  Agreement  or the  matters  contemplated  hereby and it
agrees that process may be served upon it in any manner  authorized  by the laws
of the State of  California  for such  persons and waives and  covenants  not to
assert or plead any objection which it might otherwise have to such jurisdiction
and such process.

                    The parties hereto agree that they have been  represented by
counsel during the negotiation, preparation and execution of this Agreement and,
therefore,  waive the  application  of any law,  regulation,  holding or rule of
construction  providing that  ambiguities in an agreement or other document will
be construed against the party drafting such agreement or document.


                                       50

<PAGE>


         IN WITNESS WHEREOF,  A2S, EMCON and the Shareholders' Agent have caused
this Agreement to be executed and delivered by each of them or their  respective
officers thereunto duly authorized, all as of the date first written above.

"EMCON"

EMCON

By:    \o\ R. Michael Momboisse
       ----------------------------

Name:  R. Michael Momboisse
       ----------------------------

Title: CFO and VP Legal
       ----------------------------


"SUB"

ADVANCED ANALYTICAL SOLUTIONS 
   DELAWARE , INC.,
   a Delaware corporation

By:    \o\ R. Michael Momboisse
       ----------------------------

Name:  R. Michael Momboisse
       ----------------------------

Title: President
       ----------------------------


"A2S"
ADVANCED ANALYTICAL SOLUTIONS, 
   INCORPORATED,
   a Colorado corporation

By:    \o\ William J. Hengemihle
      ----------------------------

Name:  William J. Hengemihle
      ----------------------------

Title: President
      ----------------------------


                                       51


<PAGE>







"A2S SHAREHOLDERS"

\o\  William J. Hengemihle
- ------------------------------
William J. Hengemihle


\o\ Christopher M. Wittenbrink
- ------------------------------
Christopher M. Wittenbrink


\o\ Timothy M. Keaten
- ------------------------------
Timothy M. Keaten



                                       52
<PAGE>


List of Exhibits

Exhibit A             -        Certificate of Merger

Exhibit B-1           -        Legal Opinion of EMCON

Exhibit B-2           -        Legal Opinion A2S

Exhibit C             -        Employment and Non-Competition Agreement

Exhibit D             -        Consulting Agreement

Exhibit E             -        Promissory Note and Pledge Agreement

Exhibit F             -        Registration Rights Agreement


                                       53
<PAGE>

<TABLE>
<CAPTION>

                                                   Schedule 1.7

                                               Merger Consideration

    A2S SHAREHOLDER           STATE OF              NO. SHARES A2S                    CASH                        EMCON
                              RESIDENCE              COMMON STOCK                  CONSIDERATION               COMMON STOCK
    ---------------           --------              --------------                 -------------               ------------  
<S>                         <C>                          <C>                        <C>                            <C>

 William J. Hengemihle      Pennsylvania                 30,000                     $272,727                       55,944

   Timothy M. Keaten          Colorado                   30,000                     $272,727                       55,944

     Christopher M.           Colorado                    6,000                      $54,545                       11,189
      Wittenbrink

         Total                                           66,000                     $599,999                      123,077

</TABLE>

                                       54


                                  EXHIBIT 10.29

                                      EMCON

                          REGISTRATION RIGHTS AGREEMENT

     THIS REGISTRATION  RIGHTS AGREEMENT is entered into as of April 3, 1998, by
and  among  EMCON,  a  California  corporation  ("EMCON")  and  the  undersigned
shareholders  of Advanced  Analytical  Solutions,  Inc., a Colorado  corporation
("A2S")  (collectively,  the "Shareholders"),  such Shareholders having received
certain rights to register  shares of EMCON common stock to be received upon the
merger (the "Merger") of A2S with and into Advanced Analytical Solutions,  Inc.,
a Delaware  corporation  and a  wholly-owned  subsidiary of EMCON ("Sub") as set
forth in the  Agreement  and Plan of  Reorganization  dated  April 3,  1998 (the
"Merger Agreement") among EMCON, A2S, Sub and the Shareholders.

                                    RECITALS:

     Pursuant to the terms of the Merger Agreement, EMCON desires to provide the
shareholders certain registration rights as provided for in this Agreement.


                                   AGREEMENT:

     In  consideration   of  the  mutual  promises,   covenants  and  conditions
hereinafter set forth, the parties hereto mutually agree as follows:

         1.       Registration Rights.

                  1.1      Certain  Definitions.  As used in this  Agreement,  
the  following  terms  will have the following respective meanings:

                           (a)      "Commission"  will mean the Securities  and 
Exchange  Commission  or any other federal agency at the time administering the 
Securities Act.

                           (b)      "Exchange  Act" will  mean  the Securities  
Exchange  Act  of  1934, as  amended,  or any similar  federal  statute and the
rules and regulations thereunder, all as the same will be in effect at the time.

                           (c)      "Holder" will mean any person or persons to 
whom  Registrable  Securities  were originally issued.

                           (d)      "Securities  Act" will mean the Securities
Act of  1933, as amended,  or any  similar  federal  statute and  the rules and
regulations thereunder, all as the same will be in effect at the time.

                           (e)      "Registrable  Securities"  means (i) all 
shares  of  EMCON  Common  Stock issued to the  Shareholders in connection with
the Merger,  including  shares of Common  Stock  issued in  connection  with the
Earnout Payments (as defined in the Merger  Agreement),  but excluding shares of
EMCON Common Stock issued to the  shareholders in the Merger that have been sold
or otherwise  transferred by the Shareholders who initially received such shares
in the

                                       55
<PAGE>


Merger;  (ii) all  shares of  capital  stock  issued in lieu of any of the stock
referred to in clause (i) in any reorganization, which have not been sold to the
public;  and (iii) all shares of capital  stock  issued in respect of any of the
stock  referred to in clauses (i) or (ii) as a result of any stock split,  stock
dividend, recapitalization or the like, which have not been sold to the public.

                           (f)      The  terms "register",  "registered" and 
"registration"  refer  to  a registration  effected  by  preparing  and filing a
registration   statement  in  compliance   with  the  Securities  Act,  and  the
declaration or ordering of the effectiveness of such registration statement.

                           (g)      "Registration   Expenses"  will  mean  all 
expenses  incurred  by  EMCON  in  complying  with this  Section 1,  including,
without  limitation,  all registration,  qualification and filing fees, printing
expenses,  escrow fees, fees and  disbursements  of counsel for EMCON,  blue sky
fees and expenses and the expense of any special audits  incident to or required
by any such registration (but excluding the compensation of regular employees of
EMCON which will be paid in any event by EMCON).

                           (h)      "Selling   Expenses"   will  mean  all   
underwriting  discounts  and  selling  commissions  applicable to the sale of
the  Registrable  Securities  and all fees and  expenses of legal  counsel for a
Holder.

                  1.2      Piggyback Registration

                           (a)      If at any time or from time to time,  EMCON 
will  determine  to  register  any  of  its  securities,  other  than  (i) a
registration  relating  solely to  employee  benefit  plans on Form S-1,  S-8 or
similar forms which may be promulgated in the future,  or (ii) a registration on
Form S-4 or similar forms which may be promulgated in the future relating solely
to a Commission Rule 145 transaction, EMCON will:

                                    (A)    promptly give to each Holder written
notice thereof; and

                                    (B)    include  in such  registration  (and 
     any related qualification under blue sky laws or other compliance),  and in
any underwriting involved therein, all the Registrable Securities specified in a
written request or requests,  made within twenty (20) days after receipt of such
written  notice  from EMCON,  by any Holder or  Holders,  except as set forth in
Subsection 1.2(b).

                           (b)      Underwriting.  If  the  registration  of  
which  EMCON  gives  notice is for  a  registered  public offering  involving an
underwriting,  EMCON will so advise the Holders as a part of the written  notice
given pursuant to Subsection 1.2(a)(i). In such event the right of any Holder to
registration pursuant to this Section 1.2 will be conditioned upon such Holder's
participation   in  such   underwriting  and  the  inclusion  of  such  Holder's
Registrable  Securities in the underwriting to the extent provided  herein.  All
Holders proposing to distribute their securities  through such underwriting will
(together  with EMCON and the other  shareholders,  if any,  distributing  their
securities  through such underwriting)  enter into an underwriting  agreement in
customary form with the  Underwriter  selected for such  underwriting  by EMCON.
Notwith-standing  any other  provision of this  Section 1.2, if the  Underwriter
determines  that marketing  factors require a limitation of the number of shares
to be  underwritten,  the  Underwriter  may limit the amount of securities to be
included in the registration and underwriting by EMCON's shareholders or exclude
such  securities  entirely.  The number of shares  that may be  included  in the
registration and underwriting by the Holders will be allocated among the Holders
in proportion to

                                       56
<PAGE>


the number of Registrable  Securities then held by each. If any such shareholder
disapproves  of the terms of any such  underwriting,  he may  elect to  withdraw
therefrom  by  written  notice to EMCON  and the  Underwriter.  Any  Registrable
Securities  excluded or withdrawn from such  underwriting  will be excluded from
such registration.

                  1.3  Expenses  of  Registration.   All  Registration  Expenses
incurred  in  connection  with any  registration,  qualification  or  compliance
pursuant to Section 1.2 will be borne by EMCON. All Selling Expenses relating to
securities  registered  by the  Holders  will be  borne by the  Holders  of such
securities  pro rata on the basis of the  number of  Registrable  Securities  so
registered.

                  1.4 Registration Procedures. In the case of each registration,
qualification or compliance effected by EMCON pursuant to this Agreement,  EMCON
will,  upon  request,  inform  each  Holder  as  to  the  status  of  each  such
registration, qualification and compliance. At its expense EMCON will:

                           (a)      Keep  such  registration,  and any  
qualification  or  compliance  under  state  securities  laws  which  EMCON
determines to obtain, effective for a period of one hundred eighty (180) days or
until the Holder or Holders have  completed  the  distribution  described in the
registration statement relating thereto, whichever first occurs;

                           (b)      Furnish such number of prospectuses  and 
other documents  incident thereto as a Holder from time to time may reasonably 
request; and

                           (c)      Use its efforts to register  and  qualify 
the  securities  covered  by  such  registration  statement  under  such  other
securities  or blue  sky  laws of such  jurisdictions  as  shall  be  reasonably
requested by the Holders, provided that EMCON will not be required in connection
therewith  or as a  condition  thereto to qualify  to do  business  or to file a
general consent to service of process in any such states or jurisdictions.

                  1.5 Delay of  Registration.  No Holder  will have any right to
take any action to restrain, enjoin or otherwise delay any registration pursuant
to Section 1.2 hereof as a result of any controversy that may arise with respect
to the interpretation or implementation of this Agreement.

                  1.6      Indemnification.

                           (a)     EMCON will indemnify each Holder, each of its
officers,  directors,  employees,  partners,  legal  counsel  and  accountants,
and each person  controlling such Holder within the meaning of Section 15 of the
Securities  Act,  with  respect  to which  any  registration,  qualification  or
compliance has been effected  pursuant to this Agreement,  and each underwriter,
if any,  and each  person who  controls  any  underwriter  within the meaning of
Section 15 of the Securities Act, against all expenses,  claims, losses, damages
and liabilities (or action in respect  thereof),  including any of the foregoing
incurred in settlement of any litigation,  commenced or threatened,  arising out
of or based on any untrue statement (or alleged untrue  statement) of a material
fact contained in any registration statement,  prospectus,  offering circular or
other  document,  or any amendment or supplement  thereof,  incident to any such
registration, qualification or compliance, or any omission (or alleged omission)
to state therein a material  fact required to be stated  therein or necessary to
make the  statements  therein not  misleading,  or any violation by EMCON of any
rule or regulation promulgated under the Securities Act, Exchange

                                       57
<PAGE>


Act or state  securities  laws  applicable  to EMCON and  relating  to action or
inaction   required  of  EMCON  in  connection   with  any  such   registration,
qualification  or compliance,  and will reimburse each such Holder,  each of its
officers,  directors,  employees,  partners, legal counsel and accountants,  and
each person  controlling such Holder,  each such underwriter and each person who
controls any such underwriter,  for any legal and any other expenses  reasonably
incurred in  connection  with  investigating,  preparing or  defending  any such
claim, loss, damage, liability or action; provided, however, that EMCON will not
be liable in any such case to the  extent  that any such  claim,  loss,  damage,
liability  or  expense  arises  out of or is based on any  untrue  statement  or
omission  made in  reliance  upon and in  conformity  with  written  information
furnished to EMCON by an instrument duly executed by or on behalf of such Holder
or underwriter and stated to be specifically for use therein.

                           (b)      Each Holder will, if  Registrable Securities
held  by  such  Holder  are  included  in  the  securities  as  to  which  such
registration,  qualification  or compliance is being effected,  indemnify EMCON,
each  of  its  directors,  officers,  employees,  partners,  legal  counsel  and
accountants,  each underwriter,  if any, of EMCON's securities covered by such a
registration  statement,  each  person who  controls  EMCON or such  underwriter
within the  meaning of Section  15 of the  Securities  Act,  and each other such
Holder, each of its officers, directors,  employees, partners, legal counsel and
accountants,  and each  person  controlling  such  Holder  within the meaning of
Section 15 of the  Securities  Act,  against  all  claims,  losses,  damages and
liabilities  (or  actions in  respect  thereof)  arising  out of or based on any
untrue  statement (or alleged untrue  statement) of a material fact contained in
any  such  registration  statement,   prospectus,  offering  circular  or  other
document, or any omission (or alleged omission) to state therein a material fact
required to be stated  therein or necessary to make the  statements  therein not
misleading,  and will reimburse EMCON, such Holders,  such directors,  officers,
employees,  partners,  legal  counsel,  accountants,  persons,  underwriters  or
control  persons  for any legal or any other  expenses  reasonably  incurred  in
connection  with  investigating  or  defending  any such  claim,  loss,  damage,
liability  or action,  in each case to the  extent,  but only to the extent that
such  untrue  statement  or  omission  is made in such  registration  statement,
prospectus,  offering  circular  or  other  document  in  reliance  upon  and in
conformity  with written  information  furnished to EMCON by an instrument  duly
executed  by or on behalf of such Holder and stated to be  specifically  for use
therein.  Notwithstanding the foregoing, in no event will a Holder be liable for
any such claims, losses,  damages, or liabilities in excess of the proceeds, net
of  underwriting  discounts  and  commissions,  received  by such  Holder in the
offering, except in the event of fraud by such Holder.

                           (c)      Each  party   entitled  to  indemnification 
under  this  Section  1.6  (the  "Indemnified  Party") will  give  notice to the
party required to provide  indemnification  (the "Indemnifying  Party") promptly
after  such  Indemnified  Party has  actual  knowledge  of any claim as to which
indemnity may be sought,  and will permit the  Indemnifying  Party to assume the
defense of any such claim or any litigation resulting  therefrom,  provided that
counsel for the  Indemnifying  Party, who will conduct the defense of such claim
or litigation,  shall be approved by the Indemnified  Party (whose approval will
not unreasonably be withheld), and the Indemnified Party may participate in such
defense at such party's  expense,  and provided  further that the failure of any
Indemnified  Party to give  notice  as  provided  herein  will not  relieve  the
Indemnifying Party of its obligations under this Agreement,  unless such failure
is prejudicial to the Indemnifying  Party in defending such claim or litigation.
No  Indemnifying  Party,  in the defense of any such claim or litigation,  will,
except  with the  consent  of each  Indemnified  Party,  consent to entry of any
judgment or enter into any settlement which does not include as an unconditional
term thereof the giving by the claimant or plaintiff to such  Indemnified  Party
of a release from all liability in respect to such claim or litigation.  Subject
to the foregoing, the Indemnifying Party will promptly


                                       58
<PAGE>


advance all expenses  incurred by the  Indemnified  party in connection with the
investigation  and  defense  of any  claim as to which  indemnity  may be sought
pursuant to this Agreement after written  request  therefor (but no earlier than
incurred) by the Indemnified  Party to the  Indemnifying  Party. The Indemnified
Party  will  repay  such  amounts  advanced  if  and to the  extent  that  it is
ultimately   determined   that  the   Indemnified   Party  is  not  entitled  to
indemnification or contribution under this Agreement.

                           (d)      If the indemnification provided for in this 
Section  1.6  is  held  by  a court of competent  jurisdiction to be unavailable
to an Indemnified Party with respect to any loss,  liability,  claim,  damage or
expense  referred  to  therein,   then  the  Indemnifying   Party,  in  lieu  of
indemnifying such Indemnified  Party  thereunder,  will contribute to the amount
paid or payable by such Indemnified  Party as a result of such loss,  liability,
claim,  damage or expense in such  proportion as is  appropriate  to reflect the
relative fault of the Indemnifying  Party on the one hand and of the Indemnified
Party on the other in connection with the statements or omissions which resulted
in such loss, liability,  claim, damage or expense as well as any other relevant
equitable  considerations.  The relative fault of the Indemnifying  Party and of
the  Indemnified  Party will be  determined by reference to, among other things,
whether  the  untrue or  alleged  untrue  statement  of a  material  fact or the
omission or alleged  omission to state a material  fact  relates to  information
supplied by the Indemnifying  Party or by the Indemnified Party and the parties'
relative intent, knowledge,  access to information and opportunity to correct or
prevent such statement or omission.

                           (e)      Notwithstanding   the   foregoing,  to  the
extent  that  the  provisions on  indemnification  and contribution contained in
any underwriting  agreement  entered into in connection with the relevant public
offering are in conflict with the foregoing  provisions,  the  provisions in the
underwriting agreement will be controlling.

                  1.7 Lockup  Agreement.  In consideration for EMCON agreeing to
its obligations under this Section 1, each Holder agrees, in connection with the
registration  of  EMCON's  securities,  that  upon the  request  of EMCON or the
Underwriter,  such Holder will not sell, make any short sale of, loan, grant any
option for the purchase of, or otherwise  dispose of any Registrable  Securities
(other  than those  included  in the  registration)  without  the prior  written
consent of EMCON or  Underwriter,  as the case may be, for a period of up to 180
days after the effective date of such registration; provided, however, that such
Holder will have no  obligation  to enter into the  agreement  described  herein
unless all executive  officers and directors of EMCON are required to enter into
similar agreements.

                  1.8 Information by Holder.  As a condition to the inclusion of
their Registrable  Securities,  the Holder or Holders of Registrable  Securities
included in any registration  will furnish to EMCON such  information  regarding
such Holder or Holders and the  distribution  proposed by such Holder or Holders
as EMCON may request in writing and as will be reasonably required in connection
with any registration,  qualification or compliance  contemplated in Section 1.2
of this Agreement.

                  1.9 Rule 144 Reporting. With a view to making available to the
Holders the benefits of certain rules and  regulations of the  Commission  which
may  permit  the  sale  of the  Registrable  Securities  to the  public  without
registration, EMCON agrees to:

                           (a)      Make and keep public information  available,
as those terms are understood and defined in Rule 144 under the Securities Act;

                                       59
<PAGE>



                           (b)      Use its best  efforts  to file  with the  
Commission  in  a  timely  manner all  reports and other  documents  required of
EMCON under the Securities Act and the Exchange Act;

                           (c)      So long as a Holder owns any unregistered  
Registrable   Securities,  furnish  to  such  Holder  upon  request a written
statement by EMCON as to its compliance with the reporting  requirements of said
Rule 144, and of the  Securities  Act and the  Exchange  Act, a copy of the most
recent annual or quarterly report of EMCON, and such other reports and documents
of EMCON as such Holder may reasonably request in availing itself of any rule or
regulation  of the  Commission  allowing  a Holder  to sell any such  securities
without registration.

                  1.10  Termination of Registration  Rights.  The obligations of
EMCON pursuant to this Section 1 will terminate with respect to any Holder, when
all of the Registrable Securities of such Holder may be sold under Rule 144 in a
three-month period.

         2.       Miscellaneous.

                  2.1 Waivers and Amendments.  With the written consent of EMCON
and the record holders of a majority of the outstanding  Registrable Securities,
any  provision  of  this  Agreement  may be  waived  (either  generally  or in a
particular  instance,  either  retroactively or  prospectively  and either for a
specified period of time or indefinitely) or amended,  and with the same consent
EMCON, when authorized by its Board of Directors, may enter into a supplementary
agreement for the purpose of adding any  provisions to or changing in any manner
or eliminating any of the provisions of this Agreement. Any waiver, amendment or
supplement to which such consents are obtained will be binding upon all Holders.
Upon the effectuation of each such waiver,  amendment or supplement,  EMCON will
promptly  give  written  notice  thereof to the Holders who have not  previously
received  notice  thereof or consented  thereto in writing.  In  addition,  each
Holder,  as to such  Holder  only,  may  consent in writing to any such  waiver,
amendment or supplement,  which will be binding upon such Holder.  No amendment,
waiver or supplement  to this  Agreement  will be effective  unless agreed to in
writing by the party against whom  enforcement  is sought or, in the case of any
Holder,  by such Holder or Holders of a majority of the outstanding  Registrable
Securities.

                  2.2  Governing  Law.  This  Agreement  will be governed in all
respects  by the laws of the State of  California  as such laws are  applied  to
agreements  between  California  residents  entered  into  and  to be  performed
entirely within California.

                  2.3  Successors  and Assigns.  Except as  otherwise  expressly
provided  herein,  the  provisions  hereof  will inure to the benefit of, and be
binding upon, the successors,  assigns,  heirs,  executors and administrators of
the parties hereto.

                  2.4 Entire  Agreement  This  Agreement,  the  exhibits to this
Agreement and the other documents  delivered  pursuant hereto or incorporated by
reference  herein  constitute  the full and entire  understanding  and agreement
between the parties with regard to the subjects hereof and thereof and supersede
all prior oral and written  understandings,  agreements  and  commitments  by or
between the parties hereto.

                  2.5  Notices,   etc.  All  notices  and  other  communications
required  or  permitted  hereunder  will be in  writing  and will be  mailed  by
certified or registered mail, postage prepaid,

                                       60
<PAGE>


addressed  (a) if to a party other than EMCON,  at the address of such party set
forth on such party's signature page to this Agreement, or at such other address
as such party  furnishes to EMCON in writing,  or (b) if to EMCON,  at 400 S. El
Camino Real, Suite 1200 San Mateo, CA 94402, Attention: Chief Financial Officer,
or at such  other  address  as EMCON  furnishes  to the  other  parties  to this
Agreement.

                  2.6 No  Waivers.  No  failure  on the  part  of any  party  to
exercise  or delay in  exercising  any right  hereunder  will be deemed a waiver
thereof,  nor will any such failure or delay, or any single or partial  exercise
of any such right,  preclude any further or other  exercise of such right or any
other right.

                  2.7 Separability.  If any provision of this Agreement,  or the
application  thereof,  is for any reason and to any extent determined by a court
of competent jurisdiction to be invalid or unenforceable,  the remainder of this
Agreement  and  the   application   of  such   provision  to  other  persons  or
circumstances  will be interpreted so as best to reasonably effect the intent of
the parties hereto.  The parties agree to use their best efforts to replace such
void or  unenforceable  provision of this Agreement with a valid and enforceable
provision  which will achieve,  to the extent greatest  possible,  the economic,
business and other purposes of the void or unenforceable provision.

                  2.8  Titles and  Subtitles.  The  titles of the  sections  and
subsections of this Agreement are for  convenience of reference only and are not
to be considered in construing this Agreement.

                  2.9 Counterparts. This Agreement may be executed in any number
of  counterparts,  each of which will be an original,  but all of which together
will constitute one instrument.

                  2.10  Attorneys'  Fees.  In the event of any  action,  suit or
proceeding for the breach of this Agreement or  misrepresentation  by any party,
the prevailing  party will be entitled to reasonable  attorneys' fees, costs and
expenses incurred in such action, suit or proceeding.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

  


                                       61
<PAGE>



         IN WITNESS WHEREOF,  the parties hereby have executed this Agreement on
the date first above written.


                                            EMCON



                                             By:\o\ R. Michael Momboisse
                                                ------------------------------

                                             Its: CFO and VP Legal
                                                  ----------------------------


                                             SHAREHOLDERS:



                                             \o\ William J. Hengemihle
                                             ---------------------------------
                                             William J. Hengemihle

                                             51 Casselberry Drive
                                             Audubon, Pennsylvania 19403


                                             \o\ Christopher M. Wittenbrink
                                             ---------------------------------
                                             Christopher M. Wittenbrink

                                             2715 South Pierce Street
                                             Denver, Colorado 80227


                                             \o\ Timothy M. Keaten
                                             ---------------------------------
                                             Timothy M. Keaten

                                             3048 East Clairton Drive
                                             Highlands Ranch, Colorado 80126



                                       62



                                  EXHIBIT 10.30

                             SECURED PROMISSORY NOTE

$225,000                                                          April 3, 1998


     FOR VALUE RECEIVED, the undersigned, Timothy M. Keaten ("Borrower"), hereby
promises to pay to EMCON, a California  corporation  ("Lender"),  or order,  the
principal sum of Two Hundred Twenty-Five  Thousand Dollars ($225,000),  together
with accrued interest as provided herein.

A.  Interest.  Interest shall accrue with respect to the principal sum hereunder
at the per annum rate equal to eight percent (8.0%).  Interest payable hereunder
shall be  calculated  on the basis of a three  hundred  sixty (360) day year for
actual days elapsed.  Interest  shall be due and payable in arrears on the first
day of each third calendar month, commencing with the first month after the date
hereof.

B.       Payment.

         1. Scheduled Payment. The principal  indebtedness plus accrued interest
thereon  shall be payable in full on the third  anniversary  of the date  hereof
(the "Payment Date").

         2. Optional  Prepayment.  Borrower shall have the right at any time and
from time to time to prepay,  in whole or in part,  the  principal of this Note,
without  payment of any premium or penalty.  Any principal  prepayment  shall be
accompanied by a payment of all interest  accrued on the amount prepaid  through
the date of such prepayment.

         3. Form of Payment.  Principal  and interest and all other  amounts due
hereunder  are to be paid in lawful  money of the  United  States of  America in
federal or other immediately  available funds. At the option of Borrower, on the
Payment  Due Date,  Borrower  may assign all right,  title and  interest  to the
Collateral (as defined  herein) to Lender and Lender shall apply the Fair Market
Value  (as  defined  in this  Section  B(3)) of the  Collateral  to the  Secured
Obligations (as defined herein), provided that Lender's securities are listed on
the Nasdaq National Market on the Payment Date. For the purposes of this Section
B, the term "Fair Market Value" shall mean the average of the closing  prices of
Lender  Common Stock for the seven  trading days  preceding the Payment Date, as
reported  on the  Nasdaq  National  Market.  If the  Fair  Market  Value  of the
Collateral is  insufficient  to pay the full amount of the Secured  Obligations,
Borrower shall be liable for the deficiency as set forth above.

C.       Security Interest.

         1. Grant of  Security  Interest.  Borrower  grants to Lender a security
interest in the Collateral,  as defined herein,  to secure the payment of all of
the  indebtedness  hereunder (the "Secured  Obligations").  Notwithstanding  the
foregoing, Borrower acknowledges that this Note is a full recourse note and that
the  undersigned  is liable for full payment of this Note without  regard to the
value at any time or from  time to time of the  Collateral.  In the event of any
default in the payment of this Note, the Company shall have and may exercise any
and all remedies of a secured party under the  California  Commercial  Code, and
any  other  remedies  available  at  law  or in  equity,  with  respect  to  the
Collateral.

                                       63
<PAGE>



         2.  Representations  and  Warranties  Regarding  Collateral.   Borrower
represents  and warrants to Lender that Borrower is the true and lawful owner of
the Collateral,  having good and marketable title thereto, free and clear of any
and all  Liens  other  than the Lien and  security  interest  granted  to Lender
hereunder.  Borrower  shall not create or assume any such Lien on or against any
of the  Collateral  except as created or  permitted  by this Note,  and Borrower
shall  promptly  notify Lender of any such other Lien against the Collateral and
shall  defend  the  Collateral  against,  and  take all  such  action  as may be
necessary to remove or discharge, any such Lien.

         3. Perfection of Security Interest. Borrower agrees to take all actions
requested  by Lender and  reasonably  necessary  to  perfect,  to  continue  the
perfection  of, and to  otherwise  give notice of, the Lien  granted  hereunder,
including, but not limited to, execution of financing statements.

D.       Events of Default.

         1. Definition of Event of Default. The occurrence of any one or more of
the following events shall constitute an "Event of Default" hereunder,  provided
that Borrower has been provided  written notice of such Event of Default and has
not cured such Event of Default with twenty (20) days of receipt of such notice:

                  (i)      Borrower's breach of the obligation to pay any amount
payable  hereunder on the date that it is due and payable;

                  (ii)  Borrower's  institution  of  proceedings  against it, or
Borrower's  filing of a petition or answer or consent seeking  reorganization or
release,  under the federal  Bankruptcy Code, or any other applicable federal or
state law relating to creditor rights and remedies, or Borrower's consent to the
filing  of any such  petition  or the  appointment  of a  receiver,  liquidator,
assignee,  trustee or other similar  official of Borrower or of any  substantial
part of its property,  or Borrower's  making of an assignment for the benefit of
creditors, or the taking of action in furtherance of such action;

                  (iii) the creation  (whether  voluntary or involuntary) of, or
any attempt to create, any Lien upon any of the Collateral, or the making or any
attempt to make any levy,  seizure or  attachment  thereof and such Lien,  levy,
seizure, or attachment has not been removed,  discharged or rescinded within ten
(10) days,  provided  that the Fair Market Value (as defined in Section  D(2)(a)
below)  of the  Collateral  is less  than  110% of the  aggregate  amount of the
Secured Obligations;

                  (iv) the entry of any judgment or order against Borrower which
remains  unsatisfied  or  undischarged  and in effect for thirty (30) days after
such entry without a stay of  enforcement  or execution,  provided that the Fair
Market Value (as defined in Section  D(2)(a)  below) of the  Collateral  is less
than 110% of the aggregate amount of the Secured Obligations.

                  (v)  Borrower's  breach  of  any   representation,   warranty,
covenant  or  agreement  of  Borrower  set  forth in the  Agreement  and Plan of
Reorganization by and among Lender,  Borrower,  Advanced  Analytical  Solutions,
Inc.  ("A2S"),  the  Shareholders  of  A2S  and  Advanced  Analytical  Solutions
Delaware, Inc. dated April 3, 1998.

                                       64
<PAGE>


         2.       Rights and Remedies on Event of Default.

                  (a) During the continuance of an Event of Default and prior to
Lender  invoking its rights set forth below,  Lender agrees that upon assignment
by  Borrower to Lender of all of  Borrower's  right,  title and  interest to the
Collateral, Lender shall apply the Fair Market Value (as defined in this Section
D(2)(a))  of the  Collateral  to the  Secured  Obligations  as payment  for such
Secured  Obligations.  For the purposes of this Section D, the term "Fair Market
Value" shall mean shall mean the average of the closing  prices of Lender Common
Stock for the seven trading days preceding the initial date the Event of Default
first occurred,  as reported on the Nasdaq National  Market.  If the Fair Market
Value of the Collateral is  insufficient to cover the full amount of the Secured
Obligations,  Borrower  shall be liable for the  deficiency  and Lender shall be
entitled  to fully  exercise  its rights set forth  below.  Notwithstanding  the
foregoing,  in the event that Lender's  securities  are not listed on the Nasdaq
National  Market at the time of an Event of Default,  this Section D(2)(a) shall
have no effect and Lender  shall be  entitled to fully  exercise  its rights set
forth below.

                  (b)  During the  continuance  of an Event of  Default,  Lender
shall  have the  right,  itself or through  any of its  agents,  with or without
notice  (except as provided in Section  D(1)  above) to  Borrower  (as  provided
below), as to any or all of the Collateral, by any available judicial procedure,
or without judicial process  (provided,  however,  that it is in compliance with
the UCC),  to exercise any and all rights  afforded to a secured party under the
UCC or other  applicable law.  Without limiting the generality of the foregoing,
Lender shall have the right to sell or  otherwise  dispose of all or any part of
the  Collateral,  either at public or private sale, in lots or in bulk, for cash
or for credit,  with or without  warranties  or  representations,  and upon such
terms and conditions, all as Lender, in its sole discretion, may deem advisable,
and it shall have the right to purchase at any such sale. Borrower agrees that a
notice sent at least  fifteen (15) days before the time of any  intended  public
sale or of the time after which any  private  sale or other  disposition  of the
Collateral  is to be made  shall  be  reasonable  notice  of such  sale or other
disposition.  The  proceeds of any such sale,  or other  Collateral  disposition
shall  be  applied,  first  to  the  expenses  of  retaking,  holding,  storing,
processing  and  preparing  for sale,  selling,  and the like,  and to  Lender's
reasonable  attorneys'  fees  and  legal  expenses,  and  then  to  the  Secured
Obligations and to the payment of any other amounts  required by applicable law,
after which Lender shall account to Borrower for any surplus proceeds.  If, upon
the sale or other  disposition  of the  Collateral,  the  proceeds  thereof  are
insufficient  to pay all amounts to which Lender is legally  entitled,  Borrower
shall be liable  for the  deficiency,  together  with  interest  thereon  at the
Default Rate, and the reasonable fees of any attorneys Lender employs to collect
such deficiency.  To the extent permitted by applicable law, Borrower waives all
claims,  damages and demands against Lender arising out of the retention or sale
or lease of the  Collateral  or other  exercise of Lender's  rights and remedies
with respect thereto.

                  (c) To the extent permitted by law, Borrower covenants that it
will not at any time insist upon or plead,  or in any manner  whatever  claim or
take any benefit or advantage  of, any stay or extension  law now or at any time
hereafter in force,  nor claim,  take or insist upon any benefit or advantage of
or from  any law now or  hereafter  in  force  providing  for the  valuation  or
appraisal  of the  Collateral  or any part  thereof,  prior to any sale or sales
thereof to be made pursuant to any provision  herein  contained,  or the decree,
judgment or order of any court of competent jurisdiction; or, after such sale or
sales,  claim or exercise any right under any statute now or  hereafter  made or
enacted by any state or  otherwise  to redeem the  property  so sold or any part
thereof, and, to the full extent legally permitted,  hereby expressly waives all
benefit and advantage of any such law or laws,  and  covenants  that it will not
invoke or utilize any such law or

                                       65
<PAGE>


laws or otherwise  hinder, delay or impede  the  execution of any power herein
granted and  delegated  to Lender,  but will suffer and permit the  execution of
every such power as though no such power, law or laws had been made or enacted.

                  (d) Any sale,  whether under any power of sale hereby given or
by virtue of judicial proceedings, shall operate to divest all Borrower's right,
title, interest, claim and demand whatsoever, either at law or in equity, in and
to the Collateral sold, and shall be a perpetual bar, both at law and in equity,
against  Borrower,  its  successors  and  assigns,  and  against all persons and
entities  claiming the Collateral  sold or any part thereof under, by or through
Borrower, its successors or assigns.

                  (e) Borrower  appoints  Lender,  and any officer,  employee or
agent of Lender, with full power of substitution,  as Borrower's true and lawful
attorney-in-fact,  effective as of the date hereof,  with power, in its own name
or in the name of Borrower,  during the  continuance of an Event of Default,  to
endorse any notes, checks, drafts, money orders, or other instruments of payment
in respect of the Collateral that may come into Lender's possession, to sign and
endorse any drafts against debtors,  assignments,  verifications  and notices in
connection with accounts, and other documents relating to Collateral;  to pay or
discharge  taxes or Liens at any time levied or placed on or threatened  against
the Collateral;  to demand,  collect, issue receipt for, compromise,  settle and
sue for monies due in respect of the Collateral;  to notify persons and entities
obligated  with respect to the  Collateral to make payments  directly to Lender;
and,  generally,  to do, at Lender's  option and at Borrower's  expense,  at any
time, or from time to time, all acts and things which Lender deems  necessary to
protect, preserve and realize upon the Collateral and Lender's security interest
therein  to effect  the intent of this  Note,  all as fully and  effectually  as
Borrower might or could do; and Borrower  hereby ratifies all that said attorney
shall lawfully do or cause to be done by virtue  hereof.  This power of attorney
shall be irrevocable as long as any of the Secured Obligations are outstanding.

                  (f) All of Lender's  rights and  remedies  with respect to the
Collateral,  whether established hereby or by any other agreements,  instruments
or  documents  or by law  shall be  cumulative  and may be  exercised  singly or
concurrently.

E.       Other Provisions.

         1.       Definitions.  As used herein, the following terms shall have 
the following meanings:

         "Collateral"  means all of  Borrower's  right,  title and  interest  in
55,944 shares of the capital  stock of EMCON,  a California  corporation,  owned
beneficially and of record by borrower.

         "Lien"  means  any  lien  (statutory  or  other),   mortgage,   pledge,
hypothecation, assignment, deposit arrangement, security interest, charge, claim
or other  encumbrance of any kind (including any conditional sale or other title
retention  agreement,  and any agreement to give any security  interest) and any
agreement   to  give  or  refrain   from  giving  a  lien,   mortgage,   pledge,
hypothecation, assignment, deposit arrangement, security interest, charge, claim
or other encumbrance of any kind.

         "UCC" means the Uniform  Commercial Code in effect from time to time in
the relevant jurisdiction.

                                       66
<PAGE>


         2. Governing Law; Venue. This Note shall be governed by the laws of the
State of  California,  without  giving  effect to conflicts  of law  principles.
Borrower and Lender agree that all actions or proceedings  arising in connection
with this Note shall be tried and litigated only in the state and federal courts
located in the County of San Mateo,  State of California or, at Lender's option,
any court in which Lender  determines it is necessary or appropriate to initiate
legal or equitable proceedings in order to exercise, preserve, protect or defend
any of its rights and  remedies  under this Note or  otherwise  or to  exercise,
preserve,  protect or defend its Lien,  and the  priority  thereof,  against the
Collateral,  and  which  has  subject  matter  jurisdiction  over the  matter in
controversy.  Borrower  waives any right it may have to assert the  doctrine  of
forum non  conveniens  or to object to such  venue,  and  consents  to any court
ordered relief.  Borrower  waives personal  service of process and agrees that a
summons and complaint commencing an action or proceeding in any such court shall
be  promptly  served  and  shall  confer  personal  jurisdiction  if  served  by
registered or certified mail to Borrower.  If Borrower fails to appear or answer
any  summons,  complaint,  process or papers so served  within  thirty (30) days
after the mailing or other service thereof, it shall be deemed in default and an
order of  judgment  may be entered  against it as demanded or prayed for in such
summons,  complaint,  process  or papers.  The choice of forum set forth  herein
shall not be deemed to preclude the enforcement of any judgment obtained in such
forum,  or the taking of any action under this Note to enforce the same,  in any
appropriate jurisdiction.

         3.  Notices.  Any  notice or  communication  required  or desired to be
served,  given or delivered  hereunder shall be in the form and manner specified
below, and shall be addressed to the party to be notified as follows:

If to Lender:          EMCON
                       400 S. El Camino Real, Suite 200
                       San Mateo, California  94402
                       Attention: R. Michael Momboisse, Chief Financial Officer
                       Fax: (650) 375-0763
                       Phone: (650) 375-1522


If to Borrower:        Timothy M. Keaten
                       3048 East Clairton Drive
                       Highlands Ranch, Colorado 80126
                       Fax: (303) 292-3883
                       Phone: (303) 296-8880

or to such other address as each party  designates to the other by notice in the
manner  herein  prescribed.  Notice  shall  be  deemed  given  hereunder  if (i)
delivered  personally  or otherwise  actually  received,  (ii) sent by overnight
delivery  service,  (iii) mailed by  first-class  United  States  mail,  postage
prepaid,  registered or certified,  with return receipt requested,  or (iv) sent
via  telecopy  machine  with a  duplicate  signed  copy  sent on the same day as
provided in clause (ii) above.  Notice  mailed as provided in clause (iii) above
shall be effective  upon the  expiration  of three (3)  business  days after its
deposit in the United States mail,  and notice  telecopied as provided in clause
(iv) above shall be  effective  upon receipt of such  telecopy if the  duplicate
signed copy is sent under  clause (iv) above.  Notice  given in any other manner
described in this  section  shall be  effective  upon  receipt by the  addressee
thereof;  provided,  however, that if any notice is tendered to an addressee and
delivery  thereof is refused by such  addressee,  such notice shall be effective
upon such tender unless expressly set forth in such notice.

                                       67
<PAGE>


         4. Lender's Rights; Borrower Waivers. Lender's acceptance of partial or
delinquent payment from Borrower hereunder,  or Lender's failure to exercise any
right  hereunder,  shall not  constitute a waiver of any  obligation of Borrower
hereunder, or any right of Lender hereunder, and shall not affect in any way the
right to require full  performance at any time  thereafter.  Except as otherwise
specifically provided herein, Borrower waives presentment,  diligence, demand of
payment,  notice,  protest and all other demands and notices in connection  with
the delivery, acceptance,  performance,  default or enforcement of this Note. In
any action on this Note,  Lender need not  produce or file the  original of this
Note,  but need only file a photocopy of this Note certified by Lender be a true
and correct copy of this Note in all material respects.

         5.  Enforcement  Costs.  Borrower  shall pay all  costs  and  expenses,
including,  without limitation,  reasonable  attorneys' fees and expenses Lender
expends  or  incurs  in  connection  with  the  enforcement  of this  Note,  the
collection of any sums due hereunder,  any actions for declaratory relief in any
way related to this Note, or the protection or preservation of any rights of the
holder hereunder.

         6. Severability. Whenever possible each provision of this Note shall be
interpreted  in such manner as to be effective and valid under  applicable  law,
but if any provision is prohibited by or invalid under  applicable law, it shall
be  ineffective  to the  extent  of  such  prohibition  or  invalidity,  without
invalidating the remainder of the provision or the remaining  provisions of this
Note.

         7. Amendment Provisions.  This Note may not be amended or modified, nor
may any of its terms be waived, except by written instruments signed by Borrower
and Lender.

         8. Binding Effect.  This Note shall be binding upon, and shall inure to
the benefit of, Borrower and the holder hereof and their  respective  successors
and assigns; provided, however, that Borrower's rights and obligations shall not
be assigned or delegated  without Lender's prior written  consent,  given in its
sole discretion, and any purported assignment or delegation without such consent
shall be void ab initio.

         9. Time of Essence.  Time is of the essence of each and every provision
of this Note.

         10.  Headings.  Section  headings used in this Note have been set forth
herein for  convenience of reference  only.  Unless the contrary is compelled by
the context, everything contained in each section hereof applies equally to this
entire Note.

                                        BORROWER



                                        By_________________________________
                                          Timothy M. Keaten




                                       68

<TABLE> <S> <C>

<ARTICLE>                                   5
<LEGEND>
This  schedule  contains summary  financial  information  extracted  from  the
consolidated balance sheets,  consolidated statements of income and consolidated
statements of cash flows included in the Company's Form 10-Q for the three month
period  ended March 31,  1997,  and is qualified in its entirety by reference to
such financial statements and the notes thereto.
</LEGEND>
<CURRENCY>                                       U.S. DOLLARS
       
<S>                                              <C>
<PERIOD-TYPE>                                          3-MOS
<FISCAL-YEAR-END>                                      DEC-31-1998
<PERIOD-START>                                         JAN-1-1998
<PERIOD-END>                                           MAR-31-1998
<EXCHANGE-RATE>                                        1
<CASH>                                                    7,356,000
<SECURITIES>                                                      0
<RECEIVABLES>                                            32,439,000
<ALLOWANCES>                                                972,000
<INVENTORY>                                               2,703,000
<CURRENT-ASSETS>                                         51,111,000
<PP&E>                                                   31,618,000
<DEPRECIATION>                                           16,097,000
<TOTAL-ASSETS>                                           89,854,000
<CURRENT-LIABILITIES>                                    18,200,000
<BONDS>                                                           0
<COMMON>                                                 42,193,000
                                             0
                                                       0
<OTHER-SE>                                                        0
<TOTAL-LIABILITY-AND-EQUITY>                             89,854,000
<SALES>                                                  25,822,000
<TOTAL-REVENUES>                                         25,822,000
<CGS>                                                    13,822,000
<TOTAL-COSTS>                                            13,822,000
<OTHER-EXPENSES>                                         11,579,000
<LOSS-PROVISION>                                             73,000
<INTEREST-EXPENSE>                                          293,000
<INCOME-PRETAX>                                              55,000
<INCOME-TAX>                                                 35,000
<INCOME-CONTINUING>                                          20,000
<DISCONTINUED>                                                    0
<EXTRAORDINARY>                                                   0
<CHANGES>                                                         0
<NET-INCOME>                                                 20,000
<EPS-PRIMARY>                                    0.00
<EPS-DILUTED>                                    0.00
        

</TABLE>


© 2022 IncJournal is not affiliated with or endorsed by the U.S. Securities and Exchange Commission