EXHIBIT 10.33

                              AMENDMENT NO. 1998-1
                                       TO
                                      EMCON
                           DEFERRED COMPENSATION PLAN


                  EMCON, a California  corporation (the "Company"),  pursuant to
the power granted to it by Section 11.2 of the EMCON Deferred Compensation Plan,
dated as of August 1, 1997,  as amended  January  1, 1998 (the  "Plan"),  hereby
further amends the Plan, as follows, effective as of January 1, 1999:

1.   The first two sentences of Section 4.1 are hereby amended in their entirety
     to read as follows:


         "Each Plan  Year,  a  Participant  may  irrevocably  elect to receive a
         future  "Short-Term  Payout"  from the Plan with  respect  to such Plan
         Year's Annual Deferral Amount and  Discretionary  Company  Contribution
         Amount.  Subject to the Deduction  Limitation,  the  Short-Term  Payout
         shall be a lump sum  payment  in an amount  that is equal to the Annual
         Deferral Amount and the Discretionary  Company  Contribution Amount for
         such Plan Year, plus amounts  credited or debited thereon in the manner
         provided  in  Section  3.5  above,  determined  at the  time  that  the
         Short-Term   Payout  becomes   payable  (rather  than  the  date  of  a
         Termination of Employment)."


         The  Company  has  caused  this  Amendment  to be  signed  by its  duly
authorized officer as of the 12th day of November, 1998.


                                EMCON


                              By:    /s/ R. Michael Momboisse 
                              ---------------------------------------------- 
                              R. Michael Momboisse
                              Chief Financial Officer - Vice President Legal




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