EXHIBIT 23.1

               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

We consent to the  incorporation  by  reference in the  Registration  Statements
(Form S-8 Nos.  33-83060,  33-61369 and  33-42186)  pertaining to the EMCON 1986
Incentive  Stock Option and 1988 Stock Option Plans,  the EMCON  Employee  Stock
Purchase Plan and the EMCON  Restricted  Stock Plan of our report dated February
18, 1998, with respect to the consolidated  financial statements and schedule of
EMCON  included in the Annual Report (Form 10-K) for the year ended December 31,
1997.


                                                              ERNST & YOUNG, LLP
San Francisco, California
March 26, 1998


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