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                                                                Exhibit 10(i)


                              GUARANTEE AGREEMENT


   This GUARANTEE AGREEMENT ("Agreement") is made and entered into this 30th
day of May, 1995 by and among OHM Corporation, an Ohio corporation ("OHM"), and
WMX Technologies, Inc., a Delaware corporation ("WMX").

   WHEREAS, OHM, Rust International Inc. and WMX have entered into a Standstill
and Non-Competition Agreement, dated the date hereof (the "Standstill
Agreement"), providing for certain agreements with respect to the ownership and
voting by WMX and its affiliates of OHM Common Stock and other matters after
the date hereof; and

   WHEREAS, WMX is willing to guarantee certain indebtedness of OHM in exchange
for a warrant to purchase 700,000 shares of OHM Common Stock (the "Warrant");

   NOW, THEREFORE, in consideration of the agreements, rights, obligations, and
covenants contained herein, OHM and WMX hereby agree as follows:

  1. GUARANTEE.  (a)  WMX hereby agree to issue from time to time, for a period
of five years following the Closing, at the direction of and for the benefit of
OHM as determined by a majority of the Other Directors (as defined in the
Standstill Agreement), a guaranty or guarantees, as the case may be, of the
indebtedness of OHM and/or its subsidiaries outstanding from time to time in an
aggregate amount not to exceed the Guaranteed Amount (as defined in Section
1(b) hereof), upon the satisfaction of the following conditions in each
instance a guaranty is issued:

   (i)  the form of each such guarantee shall be reasonably satisfactory to
   WMX and the Independent Directors (as defined in the Standstill Agreement;

   (ii)  OHM shall execute and deliver to WMX a reimbursement agreement, in
   form and substance satisfactory to WMX, obligating OHM to reimburse WMX for
   any and all payments made or obligations incurred by WMX under any such
   guarantees (the "Reimbursement Obligations");

   (iii)  if required by WMX in its sole discretion and subject to clause (v)
   below, OHM shall grant WMX a perfected first priority mortgage, lien or
   security interest in such collateral owned by OHM (the "Collateral") as WMX
   shall request to secure OHM's Reimbursement Obligations;





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   (iv)  OHM shall execute and deliver such mortgages, security agreements and
   other documents, in form and substance reasonably satisfactory to WMX, and
   shall take such other action, as WMX shall reasonably request to perfect its
   mortgage, lien or security interest in the Collateral;

   (v)  in the event any of the Collateral requested by WMX is subject to a
   prior mortgage, lien, security interest, negative pledge or other
   encumbrance (the "Prior Liens"), OHM shall cause the holders of the
   indebtedness secured by such Prior Liens to execute and deliver to WMX an
   intercreditor agreement, in form and substance reasonably satisfactory to
   WMX, the effect of which is to provide WMX with a security interest, lien,
   mortgage or negative pledge in or with respect to any such Collateral pari
   passu with such Prior Liens upon any payment made by WMX under any such
   guaranty; and

   (vi)  OHM shall execute and deliver such other documents, certificates and
   opinions relating to such Guaranty as WMX may reasonably request.

  (b)  As used herein, the term "Guaranteed Amount" shall mean $62,000,000 as
of the Closing Date and thereafter shall be increased from time to time by an
amount equal to the product of (i) $13,000,000, times (ii) a fraction, (A) the
numerator of which shall be the number of shares of OHM Common Stock purchased
by WMX or its affiliates upon exercise of all or any portion of the Warrant (as
hereinafter defined) or, if WMX shall sell, assign or transfer all or any part
of the Warrant to any person other than an affiliate, the number of shares of
OHM Common Stock underlying the Warrant (or portion thereof) which are sold,
assigned or transferred, but not more in the aggregate (taking into account all
prior adjustments as a result of any exercise or sale of any portion of the
Warrant) than 700,000 and (B) the denominator of which shall be 700,000.

  2. WARRANT.  Simultaneously herewith, OHM shall issue to WMX a warrant,
exercisable for a period of five years from the date hereof, to purchase
700,000 shares of OHM Common Stock at an exercise price of $15.00 in the form
attached hereto as Exhibit A.

  3. MODIFICATION; WAIVER.  This Agreement may be modified in any manner and at
any time by written instrument executed by the parties hereto.  Any of the
terms, covenants, and conditions of this Agreement may be waived at any time by
the party entitled to the benefit of such term, covenant, or condition.

  4. PARTIES IN INTEREST; ASSIGNMENT.  This Agreement and all the provisions
hereof shall be binding upon and inure to the benefit of the parties hereto and
their respective successors and permitted assigns, but neither this Agreement
nor any of the





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rights, interests, and obligations hereunder shall be assigned by any of the
parties hereto without the prior written consent of the other parties hereto.
Nothing in this Agreement, whether expressed or implied, shall be construed to
give any person other than the parties hereto any legal or equitable right,
remedy, or claim under or in respect of this Agreement.

  5. COUNTERPARTS.  This Agreement may be executed in one or more counterparts,
     all of which shall constitute one and the same instrument.

  6. HEADINGS.  The article and section headings of this Agreement are for
convenience of reference only and shall not be deemed to alter or affect the
meaning or interpretation of any provisions hereof.

  7. GOVERNING LAW.  This Agreement shall be governed by and construed in
accordance with the internal laws of the State of Ohio applicable to contracts
made and to be performed therein.

  IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first above written.

                                    OHM CORPORATION


                                    By   /s/ Randall M. Walters 
                                      ------------------------------
                                      Name:  Randall M. Walters 
                                      Title: Vice President


                                    WMX TECHNOLOGIES, INC.


                                    By   /s/ Linda R. Witte 
                                      ------------------------------
                                      Name:  Linda R. Witte 
                                      Title: Vice President





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