UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                   FORM 10-Q/A
                                (Amendment No. 1)

(Mark One)

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

                For the quarterly period ended September 30, 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 [    ]

8,723,099 shares of Common Stock Issued and Outstanding as of November 3, 1998.



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                    INFORMATION TO BE INCLUDED IN THE REPORT
                                 Amendment No. 1

     The undersigned registrant hereby amends its Form 10-Q for the period ended
September 30, 1998 filed with the Securities and Exchange Commission on November
6, 1998, to include the following disclosure.

Year 2000

Impact  of Year  2000:  The year 2000  (Y2K)  issue is the  result  of  computer
programs  being written  using two digits rather than four to define  applicable
years. Any of the Company's computer programs that have time-sensitive  software
may recognize a date using "00" as the year 1900 rather than the year 2000. This
could  result in a system  failure or  miscalculations  causing  disruptions  of
operations,  including,  among other  things,  a temporary  inability to process
transactions, send invoices, or engage in similar normal business activities.

The Company's  State of  Readiness:  The Company is in the process of completing
its internal analysis of potential Y2K compliance  issues.  Internal surveys are
being completed to identify  potential  hardware and software concerns and other
potential  non-IT  systems that may be affected.  During 1998, the Company began
testing its internal  systems for Y2K compliance and anticipates  completing the
testing  phase in the first  quarter of 1999.  The  Company  has begun to review
third party vendor/suppliers and customers that management believes could have a
material  effect to its  business,  to  ascertain  if, and when they will be Y2K
compliant.  Survey letters to these third parties will be  distributed  early in
the first quarter of 1999. Information supplied by third parties will be entered
into a database  and  reviewed  by the  Company's  IT  department  and  business
managers to determine  whether there are any potential  issues.  Once issues are
identified  (second  quarter of 1999),  senior  management  will determine their
potential impact to the Company's business and develop action plans accordingly.

The Cost to Address the  Company's  Year 2000 Issues:  Budgets for the Company's
internal computer, network, phone and related system needs were completed in the
fourth quarter of 1998. It is anticipated  that the costs to bring these systems
into  Y2K  compliance  is  approximately  $1,850,000;  consisting  primarily  of
software  updates,  computer  replacements,  telephone  system changes and other
costs, including disposition of assets, and outside consulting.  The majority of
these  costs are being  incurred in the  ordinary  course of business as part of
EMCON's normal replacement/upgrade program for it's computer, network, telephone
and related systems. It is expected that 40%, 35%, 20% and 5% of the total costs
will  be  incurred  in  first,  second,  third  and  fourth  quarters  of  1999,
respectively. Approximately $1,000,000 of the $1,850,000 estimated costs will be
financed through  multi-year  operating leases. The costs of the project and the
dates on which the Company believes it will complete the Y2K  modifications  are
based on management's  best  estimates,  which were derived  utilizing  numerous
assumptions of future events.

The Company  believes it will be able to test and remedy the majority of any Y2K
issues utilizing its existing IT staff with minimal use of outside consultants.

The Risks of the Company's Year 2000 Issues: The Company does not expect the Y2K
project to have a significant  effect on  operations.  At this time, the Company
believes  that any internal  Y2K issues can be resolved  prior to the year 2000.
The potential impact of Y2K issues on the Company's two reporting segments,  the
PSD and EOC is expected to be somewhat different.  PSD, a consulting  operation,
has less exposure due to the personal services nature of its business. A portion
of EOC's revenues,  however, involve the use of sophisticated equipment which at
this time, based on initial  testing,  the Company believes to be Y2K compliant.
To date, the Company has not received from its vendors,  any indication that the
Company would not be able to receive necessary  supplies for its construction of
fabrication processes.

The Company's  Contingency  Plans: The Company has not established a contingency
plan to address  unexpected  failures due to Y2K problems.  Internal  testing of
systems should be substantially finished prior to April, 1999. The Company plans
to evaluate the status of completion of its internal testing and the information
supplied by its vendors and customers in June, 1999 and determine whether such a
plan is necessary.


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                                   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:  March 11, 1999                     EMCON


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