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