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                            STOCK PURCHASE AGREEMENT

                                 BY AND BETWEEN

                        HUIZENGA FAMILY FOUNDATION, INC.

                                       AND

                                 OHM CORPORATION

                           DATED AS OF MARCH 28, 1995

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                                TABLE OF CONTENTS



Section                                                                                                        Page
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RECITALS ...................................................................................................     1

ARTICLE I.  ISSUANCE AND PURCHASE OF COMMON STOCK ..........................................................     1

     1.1      Sale of Common Stock .........................................................................     1
     1.2      Legend                                                                                             1

ARTICLE II.  CLOSING .......................................................................................     2

ARTICLE III.  REPRESENTATIONS AND WARRANTIES OF THE ISSUER .................................................     2

     3.1      Corporate Status .............................................................................     2
     3.2      Power and Authority ..........................................................................     3
     3.3      Non-Contravention ............................................................................     3
     3.4      Consents/Approvals ...........................................................................     3
     3.5      Enforceability ...............................................................................     3
     3.6      Capitalization ...............................................................................     4
     3.7      SEC Reports ..................................................................................     4
     3.8      Governing Documents ..........................................................................     4
     3.9      Financial Statements .........................................................................     4
     3.10     Changes Since December 31, 1994. .............................................................     5
     3.11     Litigation. ..................................................................................     5

ARTICLE IV.  REPRESENTATIONS AND WARRANTIES OF INVESTOR ....................................................     5

     4.1      Corporate Status .............................................................................     5
     4.2      Power and Authority ..........................................................................     5
     4.3      Non-Contravention ............................................................................     5
     4.4      Consents/Approvals ...........................................................................     6
     4.5      Enforceability ...............................................................................     6
     4.6      Affiliate of WMX Technologies, Inc. ..........................................................     6
     4.7      Investment Intent ............................................................................     6
     4.8      Investor Knowledge. ..........................................................................     7
     4.9      No Commissions ...............................................................................     7

ARTICLE V.  COVENANTS ......................................................................................     7

     5.1      Covenants of the Issuer and the Investor .....................................................     7
     5.2      Additional Covenant of Investors .............................................................     8







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                                TABLE OF CONTENTS

                                   (CONTINUED)



Section                                                                                                       Page
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ARTICLE VI.  DEFINITIONS .................................................................................       8

     6.1      Defined Terms ..............................................................................       8
     6.2      Other Definitional Provisions ..............................................................      10

ARTICLE VII.  REGISTRATION RIGHTS ........................................................................      11

     7.1      Transfer of Registration Rights ............................................................      11
     7.2      Piggyback Registration .....................................................................      11
     7.3      Holder Requested Registration ..............................................................      12
     7.4      Registration Procedures ....................................................................      13
     7.5      Further Information ........................................................................      16
     7.6      Registration During Holding Period .........................................................      16

ARTICLE VIII.  INDEMNIFICATION ...........................................................................      16

     8.1      Indemnification Relating to Registration Rights ............................................      16
     8.2      Indemnification Procedures .................................................................      18

ARTICLE IX.  MISCELLANEOUS ...............................................................................      19

     9.1      Notices ....................................................................................      19
     9.2      Non-Waiver of Remedies and Actions .........................................................      20
     9.3      Headings ...................................................................................      20
     9.4      Counterparts ...............................................................................      20
     9.5      Successors and Assigns .....................................................................      20
     9.6      Survival ...................................................................................      20
     9.7      Enforceability .............................................................................      20
     9.8      Law Governing ..............................................................................      20
     9.9      Severability ...............................................................................      20
     9.10     Remedies ...................................................................................      20
     9.11     Expenses ...................................................................................      21
     9.12     Entire Agreement ...........................................................................      21








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                            STOCK PURCHASE AGREEMENT

                  This STOCK PURCHASE AGREEMENT (this "Agreement") is entered
into as of March 28, 1995, by and between HUIZENGA FAMILY FOUNDATION, INC.
(together with its permitted successors and assigns, the "Investor"), and OHM
CORPORATION, an Ohio corporation (together with its permitted successors and
assigns, the "Issuer"). Capitalized terms used herein but not otherwise defined
herein are defined in Section 6.1.

                                    RECITALS

                  WHEREAS, subject to the terms and conditions set forth herein,
Investor desires to purchase, and Issuer desires to issue and sell to Investor,
certain shares of Issuer's common stock, par value $.10 per share (the "Common
Stock").

                  NOW, THEREFORE, in consideration of the promises and mutual
covenants contained herein, the parties hereto agree as follows:

                                   ARTICLE I.

                      ISSUANCE AND PURCHASE OF COMMON STOCK

                  1.1 Sale of Common Stock. Subject to the terms and conditions
set forth herein, and simultaneously with the execution and delivery of this
Agreement, Issuer will sell to Investor and Investor will purchase from Issuer
for an aggregate purchase price of four million five hundred thousand dollars
($4,500,000) (the "Purchase Price"), five hundred thousand (500,000) shares of
Common Stock (the "Shares"). Pursuant to such purchase and sale, Investor will
pay, by wire transfer of immediately available funds to an account designated in
writing by the Issuer, the Purchase Price for all of the Shares and the Issuer
will deliver to Investor certificates for the Shares duly registered in the name
of Investor or its designee.

                  1.2      Legend.  Any certificate or certificates representing
the Shares shall bear the following legend:

                  THE SECURITIES EVIDENCED HEREBY HAVE NOT BEEN REGISTERED UNDER
                  THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT") OR UNDER
                  ANY APPLICABLE STATE LAW AND MAY NOT BE TRANSFERRED, SOLD OR
                  OTHERWISE DISPOSED OF IN THE ABSENCE OF AN EFFECTIVE
                  REGISTRATION




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                  UNDER THE ACT OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY
                  TO THE ISSUER THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE
                  ACT AND THE RULES AND REGULATIONS PROMULGATED THEREUNDER OR
                  UNDER APPLICABLE STATE SECURITIES LAWS, AND FURTHER PROVIDED
                  THAT SUCH TRANSFER IS EFFECTED IN ACCORDANCE WITH THE
                  PROVISIONS OF SECTION 5.2(b) OF THAT CERTAIN STOCK PURCHASE
                  AGREEMENT BY AND BETWEEN THE ISSUER AND HUIZENGA FAMILY
                  FOUNDATION, INC., DATED AS OF MARCH 28, 1995.

                                   ARTICLE II.

                                     CLOSING

                  The closing of the transactions contemplated herein (the
"Closing") shall occur concurrently with the execution and delivery of this
Agreement. At the Closing the following shall occur:

            (i)  Investor shall pay, by wire transfer of immediately available
                 funds to an account designated in writing by Issuer, the
                 Purchase Price set forth in Section 1.1;

           (ii)  Issuer shall deliver to Investor the Shares, each duly
                 registered in the name of Investor;

          (iii)  Investor shall deliver to Issuer a Certificate, in a form
                 satisfactory to Issuer, of Investor certifying that Investor is
                 not an Affiliate of WMX Technologies, Inc.

                                  ARTICLE III.

                  REPRESENTATIONS AND WARRANTIES OF THE ISSUER

                  Issuer represents and warrants to Investor (which
representations and warranties shall not be required or deemed to be updated or
made applicable to any time after the Closing Date) as follows:

                  3.1      Corporate Status.  (a)  The Issuer is a corporation 
duly organized validly existing and in good standing under the laws of the State
of Ohio.



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                  (b) The Issuer has all requisite corporate power and authority
to own or lease and operate its properties and to carry on its business as now
conducted.

                  (c) The Issuer is qualified to do business in all
jurisdictions where its ownership, lease or operation of property or the conduct
of its business requires such qualification, except where the failure to so
qualify would not have a Material Adverse Effect on the Issuer and its
Subsidiaries taken as a whole.

                  3.2 Power and Authority. The Issuer has the corporate power
and authority to execute and deliver, and to perform its obligations under this
Agreement and the transactions contemplated hereby and thereby, and has taken
all necessary corporate action to authorize the execution, delivery and
performance of this Agreement and the transactions contemplated hereby and
thereby.

                  3.3 Non-Contravention. None of the execution and delivery by
the Issuer of this Agreement, the consummation of the transactions contemplated
hereby, or the compliance by Issuer with the terms and provisions hereof
(including, without limitation, the issuance to Investor by the Issuer of Shares
as contemplated by and in accordance with this Agreement), violates or will
violate the Amended and Restated Articles of Incorporation or Regulations of the
Issuer or any Requirement of Law applicable to the Issuer, conflicts with or
will conflict with or results or will result in any breach of any term,
condition or provision of, constitutes or will constitute (with due notice or
lapse of time or both) a default under, or results in the creation or imposition
of any Lien upon any of the capital stock or properties or assets of the Issuer
pursuant to the terms of, any mortgage, deed of trust or other material
agreement or instrument to which the Issuer is a party or by which it or any of
its properties is bound, or results in the creation or imposition of any Lien
upon any of the capital stock or properties or assets of the Issuer pursuant to
the terms of any other agreement or instrument to which the Issuer is a party or
by which it or any of its properties is bound.

                  3.4 Consents/Approvals. (a) No consents, filings,
authorizations or other actions of any Governmental Authority are required for
the Issuer's execution, delivery and performance of this Agreement.

                  (b) No consent, approval, waiver or other action by any Person
under any contract, agreement, indenture, lease, instrument or other document to
which the Issuer or any of its Subsidiaries is a party or by which any of them
is bound is required or necessary for the execution, delivery and performance by
the Issuer of this Agreement or the consummation of the transactions
contemplated hereby.

                  3.5 Enforceability. This Agreement has been duly executed and
delivered by the Issuer and constitutes a legal, valid and binding obligation of
the Issuer enforceable against it in accordance with its terms, except as the
same may be limited by public policy restrictions insofar as certain provisions
herein concern rights of indemnification and except as enforceability may be
limited by applicable bankruptcy, insolvency, reorganization,



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moratorium or similar laws affecting the enforcement of creditors' rights
generally and general equitable principles.

                  3.6 Capitalization. The authorized capital stock of Issuer
consists of 52,000,000 shares, of which 50,000,000 are shares of Common Stock
and 2,000,000 are shares of preferred stock. As of the date hereof, 15,636,465
shares of Common Stock are validly issued and outstanding, fully paid, and
non-assessable, and no shares of preferred stock are issued or outstanding.
Except for 2,850,000 shares of Common Stock issuable pursuant to the OHM
Corporation 1986 Stock Option Plan, as amended (the "1986 Stock Option Plan"),
1,000,000 shares of Common Stock issuable pursuant to the OHM Corporation
Nonqualified Stock Option Plan for Directors (the "Directors' Option Plan"),
100,000 shares of Common Stock issuable pursuant to the Deferred Fee Plan for
Directors (the "Deferred Fee Plan") and 2,395,833 shares of Common Stock
issuable pursuant to conversion of the OHM 8% Convertible Subordinated
Debentures due 2006 (the "Convertible Debentures"), in each case issuable as of
the date hereof, and 10,368,000 shares of Common Stock issuable to Rust
International Inc. pursuant to the Rust Agreement, no other shares of Common
Stock or preferred stock or any rights, agreements, or commitments of any kind
obligating Issuer to issue or sell any other shares of Common Stock or preferred
stock are or will be outstanding or have been or will be authorized. Upon
delivery of the Shares and payment of the Purchase Price such Shares shall be
validly issued, fully paid and non-assessable shares of Common Stock.

                  3.7 SEC Reports. The Annual Reports on Form 10-K for the year
ended December 31, 1993 and Quarterly Reports on Form 10-Q for the quarters
ended March 31, 1994, June 30, 1994 and September 30, 1994, of the Issuer filed
with the SEC under the Exchange Act, and all other reports and Proxy Statements
required to be filed by the Issuer, including, without limitation, a preliminary
proxy statement filed February 24, 1995 which includes financial statements for
the year ended December 31, 1994, have been duly and timely filed by the Issuer
(all such reports, collectively, the "SEC Reports"). The SEC Reports, when
filed, complied in all material respects with all applicable requirements of the
Exchange Act. None of the SEC Reports, at the time of filing, contained any
untrue statement of a material fact or omitted to state a material fact required
to be stated therein or necessary in order to make the statements therein not
misleading in light of the circumstances in which they were made. Issuer has
delivered to Investor true, accurate and complete copies of the SEC Reports, as
amended, and as in effect as of the date hereof.

                  3.8 Governing Documents. Issuer has delivered to Investor
true, accurate and complete copies of Issuer's Amended and Restated Articles of
Incorporation and Regulations in effect as of the date hereof.

                  3.9 Financial Statements. Each of the balance sheets included
in the SEC Reports (including any related notes and schedules) fairly presents
the consolidated financial position of the Issuer as of its date, and the other
financial statements included in the SEC Reports (including any related notes
and schedules) fairly present the consolidated results of operations or other
information included therein of Issuer for the periods or as of the dates
therein set forth in accordance with GAAP consistently applied during the
periods involved



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(except that the interim reports are subject to normal recording adjustments
which might be required as a result of year end audit and do not contain all
required footnote disclosures, and except as otherwise stated therein).

                  3.10 Changes Since December 31, 1994. Since December 31, 1994
there has been no Material Adverse Change in the Issuer. There has not been any
direct or indirect redemption, purchase or other acquisition of any shares of
the Issuer's capital stock, or any declaration, setting aside or payment of any
dividend or other distribution by the Issuer in respect of its capital stock, or
any issuance of any shares of capital stock of Issuer or any granting to any
person of any option to purchase or other right to acquire shares of capital
stock of Issuer other than pursuant to the Rust Agreement or any employee or
director stock option, stock bonus plan or other employee or director benefit
plan.

                  3.11 Litigation. There is no suit, action, or legal,
administrative or other proceeding or governmental investigation pending, or to
the best of Issuer's knowledge, threatened, anticipated or contemplated against
Issuer or any of its properties, which, in any single case or in the aggregate,
challenge or question in any respect the validity of, or would prevent or hinder
the consummation of, the transactions contemplated by this Agreement.

                                   ARTICLE IV.

                   REPRESENTATIONS AND WARRANTIES OF INVESTOR

                  Investor represents and warrants to the Issuer (which
representations and warranties shall not be required or deemed to be updated or
made applicable to any time after the Closing) as follows:

                  4.1 Corporate Status. The Investor is a corporation duly
organized validly existing and in good standing under the laws of the State of
Florida.

                  4.2 Power and Authority. The Investor has the corporate power
and authority to execute and deliver, and to perform its obligations under this
Agreement and the transactions contemplated hereby and thereby, and has taken
all necessary corporate action to authorize the execution, delivery and
performance of this Agreement and the transactions contemplated hereby and
thereby.

                  4.3 Non-Contravention. None of the execution and delivery by
Investor of this Agreement, the consummation of the transactions contemplated
hereby, or the compliance by Investor with the terms and provisions hereof,
violates or will violate any Requirement of Law applicable to Investor,
conflicts with or will conflict with or results or will result in any breach of
any terms, condition nor provisions of, constitutes or will constitute (with due
notice or lapse of time or both) a default under, any mortgage, deed of trust or
other agreement or instrument to which Investor is a party or by which it or any
of its properties is bound, other than such violations, conflicts, defaults or
breaches which,



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individually and in the aggregate, do not and will not materially and adversely
impair Investor's ability to perform its obligations hereunder or to consummate
the transactions contemplated hereby.

                  4.4 Consents/Approvals. (a) No consents, filings,
authorizations or actions of any Governmental Authority are required for
Investor's execution, delivery and performance of this Agreement, other than
compliance with any applicable requirements of the Exchange Act.

                  (b) No consent, approval, waiver or other actions by any
person (other than any Government Authority referred to in Section 4.4(a) above)
under any contract, agreement, indenture, lease, instrument or other document to
which Investor or any of its Subsidiaries is a party or by which any of them is
bound is required or necessary for the execution, delivery and performance by
Investor of this Agreement or the consummation of the transactions contemplated
hereby.

                  4.5 Enforceability. This Agreement has been duly executed and
delivered by Investor and constitutes a legal, valid and binding obligation of
Investor enforceable against it in accordance with its terms, except as
enforceability may be limited by applicable bankruptcy, insolvency,
reorganization moratorium or similar laws affecting the enforcement of
creditor's rights generally and general equitable principles.

                  4.6 Affiliate of WMX Technologies, Inc.. Investor is not an
Affiliate of WMX Technologies, Inc.

                  4.7 Investment Intent. Investor is acquiring the Shares
hereunder for its own account and with no present intention of distributing or
selling such Shares in violation of the Securities Act or any applicable state
securities law. Investor agrees that it will not sell or otherwise dispose of
any of the Shares unless such sale or other disposition has been registered
under the Securities Act or, in the opinion of counsel reasonably satisfactory
to the Issuer, is exempt from registration under the Securities Act and has been
registered or qualified or, in the opinion of such counsel, is exempt from
registration or qualification under applicable state securities laws. Investor
understands that the sale of the Shares being acquired by it hereunder have not
been registered under the Securities Act by reason of their contemplated
issuance in transactions exempt from the registration and prospectus delivery
requirements of the Securities Act pursuant to Section 4(2) thereof, and that
the reliance of the Issuer on such exemption from registration is predicated in
part on these representations and warranties of Investor. Investor acknowledges
that pursuant to Section 1.2 a restrictive legend consistent with the foregoing
has been or will be placed on the certificates for the Shares and related stop
transfer instructions will be noted in the transfer records of the Issuer and/or
its transfer agent for the shares of Issuer's Common Stock. Issuer acknowledges
that, with respect to the requirement of counsel reasonably satisfactory to
Issuer contemplated by this Section and the Legend set forth in Section 1.2
hereof, the law firm of Akerman, Senterfitt & Eidson, P.A., Miami, Florida, is
such reasonably satisfactory counsel.



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                  4.8 Investor Knowledge. Investor is an accredited investor as
such term is defined in Rule 501 of the General Rules and Regulations under the
Securities Act, and, either alone or with its financial advisor(s), has such
knowledge and experience in financial and business matters that it is capable of
evaluating the merits and risks of the investment to be made by it hereunder.
Investor acknowledges that no representations or warranties of any type or
description have been made to it by any Person with regard to the Issuer, any of
its Subsidiaries, any of their respective businesses, properties or prospects or
the investment contemplated herein, other than the representations and
warranties set forth in Article III hereof.

                  4.9 No Commissions. Investor has not incurred any obligation
for any finder's or broker's or agent's fees or commissions in connection with
the transactions contemplated hereby.

                                   ARTICLE V.

                                    COVENANTS

                  5.1 Covenants of the Issuer and the Investor. (a) Filings.
Each of Investor and Issuer shall make on a prompt and timely basis all
governmental or regulatory notifications and filings required to be made by it
for the consummation of the transactions contemplated hereby.

                  (b) Public Announcements. Except as required by Law or the
policies or rules of any stock exchange (or the NASDAQ-NMS) on which the
Issuer's securities are listed as of the date hereof, the form and content of
all press releases or other public communications of any sort relating to the
subject matter of this Agreement, and the method of their release, or
publication thereof, shall be subject to the prior approval of the parties
hereto, which approval shall not be unreasonably withheld or delayed.

                  (c) Further Assurances. Each party shall execute and deliver
such additional instruments and other documents and shall take such further
actions as may be necessary or appropriate to effectuate, carry out and comply
with all of the terms of this Agreement and the transactions contemplated hereby
and thereby.

                  (d) Cooperation. The Issuer and Investor each agree to
cooperate with the other in the preparation and filing of all forms,
notifications, reports and information, if any, required or reasonably deemed
advisable pursuant to any Requirement of Law or the rules of any exchange on
which the Common Stock is traded or the NASDAQ-NMS in connection with the
transactions contemplated by this Agreement and to use their respective
reasonable best efforts jointly to agree on a method to overcome any objections
by any Governmental Authority to any such transactions. Except as may be
specifically required hereunder, neither of the parties hereto or their
respective Affiliates shall be required to agree to take



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any action that in the reasonable opinion of such party would result in or
produce a Material Adverse Effect.

                  5.2 Additional Covenant of Investors. (a) Investor represents,
warrants, covenants and agrees that (i) it will provide to the Issuer for
inclusion in the Issuer's Proxy Statement for the 1995 Annual Meeting of
Shareholders (the "Proxy Statement") all information concerning Investor and its
Affiliates requested by Issuer and necessary for the preparation of the Proxy
Statement and (ii) such information will not contain any material misstatement
of fact or omit to state any material fact necessary to make the statements, in
light of the circumstances under which they are made, not misleading.

                  (b) Investor agrees, except as otherwise required by law or
regulatory directive, not to sell or otherwise dispose of any of the Shares
directly or indirectly held by Investor during the Holding Period.
Notwithstanding anything in this Section 5.2 to the contrary, Investor may make
any such sale, transfer or disposition to an Affiliate of Investor which agrees
to be bound by the provisions contained in this Section; provided that such
Affiliate holding such Shares is prevented (in a manner reasonably satisfactory
to the Issuer) from transferring such Shares, by dividend, distribution or
otherwise, to any entity that is not an Affiliate of Investor, until the end of
the Holding Period. Any such agreement of Affiliates of Investor shall be in
writing in a form reasonably satisfactory to the Issuer. The Issuer may impose
stop-transfer instructions with respect to the Shares subject to the foregoing
restrictions set forth above until the end of the Holding Period.

                                   ARTICLE VI.

                                   DEFINITIONS

                  6.1 Defined Terms. As used herein the following terms shall
have the following meanings:

                  "Affiliate" shall have the meaning ascribed to it in Rule
12b-2 of the General Rules and Regulations under the Exchange Act, as in effect
on the date hereof.

                  "Articles of Incorporation" means the Issuer's Amended and
Restated Articles of Incorporation, as the same may be supplemented, amended or
restated from time to time.

                  "Closing" has the meaning specified in ARTICLE II of this
Agreement.

                  "Common Stock" has the meaning specified in the Recitals to
this Agreement.

                  "Cutback Registration" means any registration in which the
managing underwriter advises the Issuer that marketing factors require a
limitation of the number of shares of Common Stock to be underwritten in such
registration.



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                  "Electing Holder" means any holder of Common Stock, other than
holders of Registrable Securities (in their respective capacities as such), who
has the right to request inclusion of Common Stock held by such holder in a
registration;

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

                  "GAAP" means generally accepted accounting principles in
effect in the United States of America from time to time.

                  "Governmental Authority" means any nation or government, any
state or other political subdivision thereof, and any entity or official
exercising executive, legislative, judicial, regulatory or administrative
functions of or pertaining to government.

                  "Holding Period" means the period of time during which
Investor may not transfer any portion of its interest in the Shares commencing
as of the date of Closing and ending upon the earliest to occur of (i)
consummation of the transactions contemplated by the Rust Agreement, (ii)
termination of the Rust Agreement, or (iii) September 30, 1995.

                  "Issuer" means OHM Corporation, an Ohio corporation.

                  "Law" means any domestic or foreign, federal, state or local
law, statute, ordinance, rule or regulation.

                  "Lien" means any mortgage, pledge, security interest,
encumbrance, lien or charge of any kind (including any conditional sale or other
title retention agreement, any lease in the nature thereof, and the filing of or
agreement to give any financing statement under the Uniform Commercial Code or
comparable law or any jurisdiction in connection with such mortgage, pledge,
security interest, encumbrance, lien or charge).

                  "Material Adverse Change (or Effect)" means a change (or
effect), in the financial condition or results of operations which change
individually or in the aggregate, is materially adverse to such financial
condition or results of operations.

                  "Person" means an individual, partnership, corporation,
business trust, joint stock company, trust, unincorporated association, joint
venture, Governmental Authority or other entity, of whatever nature.

                  "Piggyback Registration" has the meaning specified in Section
7.1(a) of this Agreement.

                  "Purchase Price" has the meaning specified in Section 1.1 of
this Agreement.

                  "Register", "registered" and "registration" refer to a
registration of the offering and sale of Common Stock effected by preparing and
filing a registration statement in compliance with the Securities Act and the
declaration or ordering of the effectiveness of such registration statement.



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                  "Registrable Securities" means any of the Shares, any shares
of Common Stock sold by the Company pursuant to that certain Stock Purchase
Agreement, dated even date herewith, between the Issuer and H. Wayne Huizenga
and shares of Common Stock issued pursuant to the First Option Agreement and the
Second Option Agreement, each dated even date herewith, between the Issuer and
H. Wayne Huizenga (collectively, the "Other Shares") and any other shares of
Common Stock or other securities issued in respect of the Shares or Other Shares
by way of stock dividend or stock split or in connection with any
recapitalization, merger, consolidation or reorganization; provided that, as to
any particular securities, such securities will cease to be Registrable
Securities when (i) they have been sold pursuant to registration or pursuant to
Rule 144 promulgated by the Securities and Exchange Commission or any similar
rule then in force ("Rule 144") or (ii) there has occurred a transfer or
assignment in respect of such Shares in violation of either of Section 5.2(b)
hereof.

                  "Requirement of Law" means as to any Person, the articles of
incorporation, by-laws or other organizational or governing documents of such
person, and any Law, or determination of any arbitrator or a court or other
Governmental Authority, in each case applicable to or binding upon such Person
or any of its properties or to which such Person or any of its property is
subject.

                  "Rust Agreement" means that Agreement and Plan of
Reorganization dated as of December 5, 1994 among the Issuer, Rust Remedial
Services Inc., Enclean Environmental Services Group, Inc., Rust Environmental,
Inc. and Rust International Inc., as the same may be supplemented, amended or
modified from time to time.

                  "SEC" means the Securities and Exchange Commission.

                  "SEC Reports" has the meaning specified in Section 3.7 of this
Agreement.

                  "Securities Act" means the Securities Act of 1933, as amended.

                  "Shares" has the meaning specified in Section 1.1 of this
Agreement.

                  "Subsidiary" means as to any Person, a corporation of which
more than 50% of the outstanding capital stock having full voting power is at
the time directly or indirectly owned or controlled by such Person.

         6.2      Other Definitional Provisions.

                  (a) All terms defined in this Agreement shall have the defined
meanings when used in any certificate, report or other documents made or
delivered pursuant hereto or thereto, unless the context otherwise requires.

                  (b) Terms defined in the singular shall have a comparable
meaning when used in the plural, and vice versa.



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                  (c) All matters of an accounting nature in connection with
this Agreement and the transactions contemplated hereby shall be determined in
accordance with GAAP applied on a basis consistent with prior periods, where
applicable.

                  (d) As used herein, the neuter gender shall also denote the
masculine and feminine, and the masculine gender shall also denote the neuter
and feminine, where the context so permits.

                  (e) The words "hereof", "herein" and "hereunder", and words of
similar import, when used in this Agreement shall refer to this Agreement as a
whole and not to any particular provision of this Agreement.

                                  ARTICLE VII.

                               REGISTRATION RIGHTS

                  Investor shall have the following registration rights with
respect to the Shares.

                  7.1 Transfer of Registration Rights. Investor may assign the
registration rights with respect to the Shares to any Affiliate as well as any
party or parties to which it may from time to time transfer the Shares; except
that Investor may transfer the demand registration rights discussed in Section
7.3 hereof only to subsequent holders of at least two hundred fifty thousand
(250,000) Shares after giving effect to the transfer of any Shares in connection
therewith. Upon assignment of any registration rights pursuant to this Section
7.1, Investor shall deliver to Issuer a notice of such assignment which includes
the identity and address of any assignee (collectively, Investor and each such
subsequent holder is referred to as a "Holder").

                  7.2      Piggyback Registration.

                  (a) From and after the Holding Period, if at any time, and
from time to time, the Issuer proposes to effect a registration for its account
or for the account of a security holder or holders (other than a registration on
Form S-8, or any similar or successor form thereto, relating to an employee or
director stock option, stock purchase or other benefit plan, or a registration
relating to shares issuable in a merger, consolidation, exchange offer, purchase
of assets or any similar transaction) ("Piggyback Registration"), the Issuer
shall:

                           (i) promptly give to each Holder of Registrable
                  Securities written notice thereof (which written notice shall
                  include a list of the jurisdictions in which the Issuer
                  intends to attempt to qualify such securities under or
                  otherwise comply with the applicable blue sky or other state
                  securities laws); and



                                       11


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                           (ii) include in such registration (and any related
                  qualification under or other compliance with blue sky or other
                  state securities laws), and in any underwriting involved
                  therein on the same terms and conditions as the securities
                  being issued thereunder, all the Registrable Securities
                  specified in a written request, made within 15 days after
                  receipt of such written notice from the Issuer, by any holder
                  of Registrable Securities; provided that if such registration
                  is a Cutback Registration, then (i) if such registration is a
                  primary registration, whether or not it includes a secondary
                  registration, on behalf of the Issuer, the Issuer shall
                  register in such registration (A) first, the shares of Common
                  Stock the Issuer proposes to sell in such registration, and
                  (B) second, shares of Common Stock held by each holder of
                  Registrable Securities and the Electing Holders on a pro rata
                  basis, based upon the number of shares of Common Stock the
                  holders of Registrable Securities and any Electing Holders
                  originally sought to include in such registration; and (ii) if
                  such registration is a Piggyback Registration which is solely
                  a secondary registration on behalf of holders of Common Stock,
                  the Issuer shall register in such registration shares of
                  Common Stock held by each holder of Registrable Securities and
                  the Electing Holders on a pro rata basis, based upon the
                  number of shares of Common Stock the holders of Registrable
                  Securities and any Electing Holders originally sought to
                  include in such registration and provided, further, that if
                  such registration is a Cutback Registration, the Issuer shall
                  use its best efforts to include all shares of Registrable
                  Securities specified in the Holder's written request, but such
                  best efforts shall not include an obligation on the part of
                  the Issuer to reduce the number of shares of the Issuer or the
                  other Electing Holders included in such Cutback Registration
                  beyond that expressly provided for in this Section.

                  (b) If the registration of which the Issuer gives notice is
pursuant to an effective registration statement under the Securities Act
involving an underwriting, the Issuer shall so advise each Holder as part of the
written notice given pursuant to subclause (i) above. In such event, the right
of each such Holder to registration pursuant to this Section shall be
conditioned upon such Holder's participation in such underwriting, the inclusion
of the Registrable Securities in the underwriting and such Holder entering into
an underwriting agreement, containing customary terms and conditions, in a form
reasonably acceptable to the Holder and the Issuer, with the underwriter or
underwriters selected for such underwriting by the Issuer; provided that if such
underwriting agreement shall not be acceptable to Holder and after reasonable
efforts by Issuer cannot be made acceptable to Holder, the Issuer may proceed
with such registration without registering the stock of Holder in such
registration.

                  7.3 Holder Requested Registration. (a) Subject to the
limitations contained in Section 7.1 and paragraph (c) of this Section 7.3,
Holder shall have the right to require the Issuer to effect any registration
with respect to the Registrable Securities held by Holder. Upon receipt of a
request for registration from Holder, the Issuer shall as soon as practicable,
use its best efforts to effect such registration, including without limitation,
the execution of an undertaking to file post-effective amendments, appropriate
qualification under



                                       12


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applicable blue sky or other state securities laws in accordance with Section
7.4(a)(v) hereof and appropriate compliance with applicable regulation issued
under the Securities Act as may be so requested and as would permit or
facilitate the sale and distribution of all or such portion of such Registrable
Securities as are specified in such request; provided that the Issuer shall not
be obligated to take any action to effect any such registration, qualification
or compliance pursuant to this Section 7.3 within 120 days immediately following
the effective date of any registration statement pertaining to an underwritten
public offering of securities of the Issuer for its own account, unless the
Holder shall have elected to include Registrable Securities in such registration
statement pursuant to Section 7.2 hereof and all of such Registrable Securities
which Holder elected to include in such registration statement were not so
included as a result of the provisions of Section 7.2(a)(ii) hereof. Holder
shall have the right to designate the managing underwriter for any registration
under this Section 7.3, which underwriter shall be reasonably acceptable to
Issuer.

                  (b) The Issuer shall file a registration statement covering
the Registrable Securities so requested to be registered as soon as practicable
after receipt of the request of Holder, but in no event sooner than thirty days
thereafter.

                  (c) Holders of Registrable Securities shall be entitled to an
aggregate 3 demand registrations and each such demand registration shall include
at least 250,000 Registrable Securities.

                  (d) The Issuer shall not be required to effect a registration
at a time when audited financial statements are not available or when the Issuer
is in possession of material information which, in the exercise of its
reasonable judgment, the Issuer deems advisable not to disclose in a
registration statement, however, the Issuer may only postpone a registration for
such reasons, in each case, for up to 60 days and not more than once during any
three month period.

                  (e) If Holder intends to distribute the Registrable Securities
covered by its request by means of an underwriting, it shall so advise the
Issuer as part of its request made pursuant to this Section. Holder shall enter
into an underwriting agreement, including best efforts or continuous offering
underwriting, in a form which is reasonably satisfactory to Holder with the
underwriter or underwriters selected for such underwriting by Holder and which
are reasonably satisfactory to the Issuer. The Issuer shall sign an agreement
with such underwriters confirming for the benefit of the underwriters its
indemnity obligations under this Agreement. The Issuer may include securities
for its own account in such registration if the underwriter so agrees and if the
number of Registrable Securities which would otherwise have been included in
such registration and underwriting would not thereby be limited.

                  (f) In the event more than one Person is a Holder of
Registrable Securities, the rights of the Holder under this Section 7.3 may be
exercised only upon election of Investor or such Holders of more than 51% of the
Registrable Securities collectively.

                  7.4 Registration Procedures. (a) In case of each registration,
qualification or compliance effected by the Issuer subject to this Article VII,
the Issuer shall keep Holder



                                       13


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advised in writing as to the initiation of each such registration, qualification
and compliance and as to the completion thereof. In addition, at its expense,
the Issuer shall:

                                 (i) before filing a registration statement or
                  prospectus or any amendment or supplements thereto subject to
                  this Article VII, the Issuer shall furnish to counsel selected
                  by Holder copies of all such documents proposed to be filed
                  and the portions of such documents provided in writing by
                  Holder for use therein and for which Holder shall indemnify
                  the Issuer shall be subject to such Holders approval;

                                (ii) prepare and file with the SEC such
                  amendments and supplements to such registration statement as
                  may be necessary to keep such registration, qualification or
                  compliance effective for a period of up to 120 days or until
                  Holder has completed the distribution described in the
                  registration statement relating thereto, whichever first
                  occurs and comply with provisions of the Securities Act with
                  respect to the disposition of all securities covered thereby
                  during such period;

                                (iii) update, correct, amend and supplement such
                  registration, qualification or compliance as necessary;

                                (iv) if such offering is to be underwritten, in
                  whole or in part, enter into a written underwriting agreement
                  containing customary terms and conditions and in form and
                  substance reasonably satisfactory to the managing underwriter
                  and the registering Holder;

                                (v) furnish such number of prospectuses,
                  including preliminary prospectuses, and other documents
                  incident thereto as Holder may reasonably request from time to
                  time, which shall be a Selling Expense;

                                (vi) register or qualify such Registrable
                  Securities under such other securities or blue sky laws of
                  such jurisdictions of the United States (up to five of which
                  shall be at the expense of the Issuer, and any additional of
                  which shall be at the expense of Holder) as Holder may deem
                  reasonable to enable it to consummate the disposition in such
                  jurisdiction of the Registrable Securities (provided that
                  Issuer will not be required to (i) qualify generally to do
                  business in any jurisdiction where it would not otherwise be
                  required to qualify but for this section, or (ii) consent to
                  general service of process in any such jurisdiction);

                               (vii) notify Holder at any time when a prospectus
                  relating to the Registrable Securities is required to be
                  delivered under the Securities Act, of the happening of any
                  event as a result of which the prospectus included in such
                  registration statement contains an untrue statement of a
                  material fact or omits any fact necessary to make the
                  statement therein not misleading, and at the request of
                  Holder, Issuer will prepare a supplement or amendment to such



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                  prospectus so that, as thereafter delivered to the purchasers
                  of such shares, such prospectus will not contain any untrue
                  statements of a material fact or omit to state any fact
                  necessary to make the statements therein not misleading;

                              (viii) cause all such Registrable Securities to be
                  listed on each securities exchange on which similar securities
                  issued by Issuer are then listed;

                                (ix) provide a transfer agent and registrar for
                  all such Registrable Securities not later than the effective
                  date of such registration statement;

                                 (x) upon the sale of any Registrable Securities
                  pursuant to such registration statement, remove all
                  restrictive legends from all certificates or other instruments
                  evidencing the Registrable Securities;

                                (xi) furnish, at the request of Holder, on the
                  date that such Registrable Securities are delivered to the
                  underwriter for sale in connection with a registration
                  pursuant to this section, if such Registrable Securities are
                  being sold through an underwriter, or if such Registrable
                  Securities are not being sold through an underwriter, on the
                  date that the registration statement with respect to such
                  Registrable Securities becomes effective, (i) an opinion dated
                  such date of the counsel representing Issuer for purpose of
                  such registration, in form and substance as is customarily
                  given to underwriters in an underwritten public offering,
                  addressed to such underwriter, if any, and to Holder; and (ii)
                  a letter dated as of such date from the independent certified
                  public accountant of Issuer, in form and substance as is
                  customarily given by independent certified public accountants
                  to underwriters in connection with a public offering,
                  addressed to the underwriter, if any, and to Holder; and

                               (xii) make available for inspection by Holder,
                  any underwriter participating in any disposition pursuant to
                  such registration statement, and any attorney, accountant or
                  any other agent retained by Holder or such underwriter, all
                  financial and other records, pertinent corporate documents and
                  properties of Issuer, and cause Issuer's officers, directors
                  and employees to supply all information reasonably requested
                  by any such Holder, underwriter, attorney, accountant or agent
                  in connection with such registration statement.

                  (b) Except as required by law, all expenses incurred by the
Issuer in complying with this Article VII, including but not limited to, all
registration, qualification and filing fees, printing expenses, fees and
disbursements of counsel for the Issuer, blue sky fees and expenses in
accordance with Section 7.4(A)(v) hereof, including fees and disbursements of
counsel related to all blue sky matters, but excluding the compensation of
regular employees of the Issuer which shall be paid in any event by the Issuer
("Registration Expenses") incurred in connection with any registration,
qualification or compliance pursuant to such Sections shall be borne by the
Issuer. All underwriting discounts and selling



                                       15


   19



commissions applicable to a sale ("Selling Expenses") incurred in connection
with any registration of Registrable Securities and the legal fees of Holder
shall be born by Holder.

                  7.5 Further Information. If Registrable Securities owned by a
Holder are included in any registration, such Holder shall furnish the Issuer
such information regarding itself and the distribution proposed by such Holder
as the Issuer may reasonably request and as shall be required in connection with
any registration, qualification or compliance referred to in this Agreement.

                  7.6 Registration During Holding Period. Issuer agrees not to
register, prior to the expiration of the Holding Period, any shares of Common
Stock under the Securities Act to which Investor's registration rights
contemplated by Section 7.2 hereof would apply unless provision is made to allow
Holder to exercise the registration rights provided for under Section 7.2
notwithstanding any requirements under the Hart-Scott-Rodino Antitrust
Improvements Act of 1976, as amended.

                                  ARTICLE VIII.

                                 INDEMNIFICATION

                  8.1 Indemnification Relating to Registration Rights. (a) With
respect to any registration, qualification or compliance effected or to be
effected pursuant to Article VII of this Agreement, the Issuer shall indemnify
each holder of Registrable Securities whose securities are included or are to be
included therein, each of such holder's directors and officers, each underwriter
(as defined in the Securities Act) of the securities sold by such holder and
each Person who controls (within the meaning of the Securities Act) any such
holder or underwriter (a "Controlling Person") from and against all losses,
damages and liabilities (or actions in respect thereof) arising out of or based
on any claim, cause of action, proceeding or litigation asserted or commenced or
threatened against any such holder or any of its officers and directors or any
such underwriter or Controlling Person concerning:

                    (i) any untrue statement (or alleged untrue statement) of a
         material fact contained in any prospectus, offering circular or other
         document (including any related registration statement, notification or
         the like) incident to any such registration, qualification or
         compliance;

                   (ii) any omission (or alleged omission) to state therein a
         material fact required to be stated therein or necessary to make the
         statement therein, in the light of the circumstances under which it was
         made, not misleading; or

                  (iii) any violation by the Issuer of the Securities Act or any
         rule or regulation promulgated thereunder applicable to the Issuer, or
         of any blue sky or other state securities laws or any rule or
         regulation promulgated thereunder applicable to the Issuer,



                                       16


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in each case, relating to action or inaction required of the Issuer in
connection with any such registration, qualification or compliance, and subject
to Section 8.2 below will reimburse each such Person entitled to indemnity under
this Section 8.1 for all legal and other expenses incurred in connection with
investigating or defending any such claim, loss damage, liability or action;
provided, however, that, the foregoing indemnity and reimbursement obligation
shall not be applicable to the extent that any such claim, loss, damage or
liability arises out of or is based on any untrue statement (or alleged untrue
statement) or omission (or alleged omission) made in reliance upon and in
conformity with written information furnished to the Issuer by or on behalf of
such a holder or by or on behalf of such an underwriter specifically for use in
such prospectus, offering circular or other document; provided, further,
however, that, with respect to any untrue statement (or alleged untrue
statement) or omission (or alleged omission) made in any preliminary prospectus,
the indemnity agreement contained in this Section shall not inure to the benefit
of any underwriter, or, if there shall be no underwriter, such other person
participating in such sale who is obligated under the Securities Act to deliver
a prospectus ("Delivering Person"), to the extent that any such losses claims,
damages or liabilities of such underwriter or Delivering Person, as the case may
be, result from the fact that there was not delivered to any Person who
purchased Registrable Securities a copy of the final prospectus relating to such
registration, as then amended or supplemented (exclusive of material
incorporated by reference) at or prior to the written confirmation of the sale
of such Registrable Securities to such Person), if (A) such delivery was
required by the Securities Act, (B) the untrue statement (or alleged untrue
statement) or omission (or alleged omission) made in such preliminary prospectus
was corrected in such final prospectus, and (C) the Issuer had previously and
timely furnished copies thereof to such underwriter or Delivering Person, as the
case may be.

                  (b) With respect to any registration, qualification or
compliance effected or to be effected pursuant to this Agreement, each holder of
Registrable Securities whose securities are included or are to be included
therein, shall indemnify the Issuer, its directors and officers, and, if and to
the extent required by the underwriters of an underwritten offering in which
such holder will be selling Registrable Securities, each underwriter (as defined
in the Securities Act) of the securities sold by such holder and each Person who
controls (within the meaning of the Securities Act) the Issuer or any such
underwriter (a "Controller") from and against all losses, damages and
liabilities (or actions in respect thereof) arising out of or based on any
claim, cause of action, proceeding or litigation asserted or commenced against
the Issuer or any of its directors and officers or any such underwriter or
Controller concerning:

                    (i) any untrue statement (or alleged untrue statement) of a
         material fact contained in any prospectus, offering circular or other
         document (including any related registration statement, notification or
         the like) incident to any such registration, qualification or
         compliance;

                   (ii) any omission (or alleged omission) to state therein a
         material fact required to be stated therein or necessary to make the
         statement therein, in the light of the circumstances under which it was
         made, not misleading; or



                                       17


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                  (iii) any violation by such holder of the Securities Act or
         any rule or regulation promulgated thereunder applicable to the Issuer
         or such holder or of any blue sky or other state securities laws or any
         rule or regulation promulgated thereunder applicable to the Issuer or
         such holder,

in each case, relating to action or inaction required of such holder in
connection with any such registration, qualification or compliance, and subject
to Section 8.2 below will reimburse each such Person entitled to indemnity under
this Section for all legal and other expenses reasonably incurred in connection
with investigating or defending any such claim, loss, damage, liability or
action; provided, however, that, the foregoing indemnity and reimbursement
obligation shall only be applicable to the extent that any such claim, loss,
damage or liability arises out of or is based on any untrue statement (or
alleged untrue statement) or omission (or alleged omission) made in reliance
upon and in conformity with written information furnished to the Issuer by or on
behalf of the holder specifically for use in such prospectus, offering circular
or other document; provided, however, that the obligations of the holder
hereunder shall be limited to an amount equal to the proceeds to the holder of
Registrable Shares sold as contemplated hereunder.

                  8.2 Indemnification Procedures. Each Person entitled to
indemnification under this Section (an "Indemnified Party") shall give notice as
promptly as reasonably practicable to each party required to provide
indemnification under this Section (an "Indemnifying Party") of any action
commenced against it in respect of which indemnity may be sought hereunder, but
failure so to notify an Indemnifying Party shall not relieve such Indemnifying
Party from any liability that it may have otherwise than on account of this
indemnity agreement so long as such failure shall not have materially prejudiced
the position of the Indemnifying Party. Upon such notification, the Indemnifying
Party shall assume the defense of such action and after such assumption the
Indemnifying Party shall not be entitled to reimbursement of any expenses
incurred by it in connection with such action except as described below. In any
such action, any Indemnified Party shall have the right to retain its own
counsel, but the fees and expenses of such counsel shall be at the expense of
such Indemnified Party unless (i) the Indemnifying Party and the Indemnified
Party shall have mutually agreed to the contrary or (ii) the named parties in
any such action (including any impleaded parties) include both the Indemnifying
Party and the Indemnified Party and representation of both parties by the same
counsel would be inappropriate due to actual or potential differing interests
between them. It is understood that the Indemnifying Party shall not, in
connection with any action in the same jurisdiction be liable for the fees and
expenses of more than one separate firm for all Indemnified Parties in addition
to any firm(s) which the Indemnifying Party may retain to represent it. The
Indemnifying Party shall not be liable for any settlement of any proceeding
effected without its written consent (which shall not be unreasonably withheld
or delayed by such Indemnifying Party), but if settled with such consent or if
there be final judgment for the plaintiff, the Indemnifying Party shall
indemnify the Indemnified Party from and against any loss, damage or liability
by reason of such settlement or judgment.



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                                   ARTICLE IX.

                                  MISCELLANEOUS

                  9.1 Notices. All notices, requests, demands, claims, and other
communications hereunder shall be in writing and shall be delivered by certified
or registered mail (first class postage pre-paid), guaranteed overnight
delivery, or facsimile transmission if such transmission is confirmed by
delivery by certified or registered mail (first class postage pre-paid) or
guaranteed overnight delivery:

                  (a)      if to Issuer to:

                           OHM Corporation
                           16406 U.S. Route 224 East
                           Findlay, Ohio 45840
                           Attention: General Counsel

                           Telecopy: (419) 424-4985

                           with a copy to:
                           Jones, Day, Reavis & Pogue
                           41 South High Street
                           1900 Huntington Center
                           Columbus, OH  43215
                           Attention:  Robert J. Gilker, Esq.

                           Telecopy:  (614) 469-4198

                  (b)      if to Investor to:
                           Huizenga Family Foundation, Inc.
                           200 South Andrews Avenue
                           Fort Lauderdale, Florida 33301
                           Attention:  Richard C. Rochon

                           Telecopy: (305) 523-0801

                           with a copy to:
                           Akerman, Senterfitt & Eidson, P.A.
                           24th Floor, One Brickell Square
                           801 Brickell Avenue
                           Miami, FL  33131
                           Attention:  Stephen K. Roddenberry, Esq.

                           Telecopy:  (305) 374-5095

                  (c)      or, in each case, at such other address or to such 
other person as may be specified in writing to the other party.



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                  9.2 Non-Waiver of Remedies and Actions. No course of dealing
between the Issuer and Investor with respect to any Common Stock, or any delay
on the part of either such party in exercising any rights available to such
party shall operate as a waiver of any right of such party, except to the extent
expressly waived in writing by such party.

                  9.3 Headings. The headings in this Agreement are for purposes
of reference only and shall not be considered in construing this Agreement.

                  9.4 Counterparts. This Agreement may be executed in any number
of counterparts, each of which when so executed and delivered shall constitute
an original and all together shall constitute one Agreement.

                  9.5 Successors and Assigns. Except as otherwise specifically
provided herein, this Agreement shall bind and inure to the benefit of the
Issuer's and Investor's respective successors and permitted assigns; provided
that neither the Issuer nor Investor shall have any right to assign any of its
rights hereunder except as otherwise specifically provided for herein, or any
interest herein without obtaining the written consent of the other to such
assignment, and any purported assignment made without obtaining such written
consent shall be null and void. Notwithstanding the foregoing, any Person who is
a holder of shares of Common Stock shall have all rights and benefits afforded
to such holder, in its capacity as such, pursuant and subject to the terms of
the Article of Incorporation.

                  9.6 Survival. Notwithstanding any investigation made by
Investor, all covenants, agreements, representations and warranties made herein
and in certificates delivered pursuant hereto shall survive the delivery to
Investor of the Common Stock to be purchased pursuant to Section 1.1.

                  9.7 Enforceability. If any term or provision of this
Agreement, or the application thereof to any Person or circumstance, shall, to
any extent, be invalid or unenforceable, the remaining terms and provisions of
this Agreement or application to other Persons and circumstances shall not be
invalidated thereby, and each term and provision hereof shall be construed with
all other remaining terms and provisions hereof to effect the intent of the
parties hereto to the fullest extent permitted by law.

                  9.8 Law Governing. This Agreement shall be construed and
enforced in accordance with and shall be governed by the laws of the State of
Ohio applicable to contracts executed by residents of that state, and fully to
be performed, in that state.

                  9.9 Severability. In the event that any provision of this
Agreement is deemed invalid, illegal or unenforceable, the validity, legality
and enforceability of the remaining provisions shall not in any way be affected
or impaired thereby.

                  9.10 Remedies. (a) Each of Investor and Issuer acknowledges
that the other party would not have an adequate remedy at law for money damages
in the event that any of the covenants or agreements of such party in this
Agreement was not performed in accordance with its terms, and it is therefore
agreed that each of Investor and Issuer in



                                       20


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addition to and without limiting any other remedy or right such party may have,
shall have the right to an injunction or other equitable relief in any court of
competent jurisdiction, enjoining any such breach and enforcing specifically the
terms and provisions hereof, and each of Investor and Issuer hereby waive any
and all defenses such party may have on the ground of lack of jurisdiction or
competence of the court to grant such an injunction or other equitable relief.

                  (b) All rights, powers and remedies provided under this
Agreement or otherwise available in respect hereof at law or in equity shall be
cumulative and not alternative, and the exercise or beginning of the exercise of
any thereof by any party shall not preclude the simultaneous or later exercise
of any other such right, power or remedy by such party.

                  9.11 Expenses. Except as otherwise expressly provided herein,
each party hereto shall bear its own expenses incurred in connection with the
negotiation, execution and performance of this Agreement.

                  9.12 Entire Agreement. This Agreement constitute the entire
understanding of the parties with respect to the subject matter hereof and
superseded all prior discussions, agreements and representations, whether oral
or written, concerning the subject matter hereof.



                                       21


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                  IN WITNESS WHEREOF, the parties hereto have caused this Stock
Purchase Agreement to be duly executed and delivered as of the day and year
first above written.

                                            OHM CORPORATION

                           By: /s/ RANDALL M. WALTERS
                              --------------------------------------------------
                           Name:   Randall M. Walters
                           Title:  Vice President, General Counsel and Secretary


                           HUIZENGA FAMILY FOUNDATION, INC.


                           By: /s/ H. WAYNE HUIZENGA
                              --------------------------------------------------
                           Name:   H. Wayne Huizenga
                           Title:  President



                                                        22