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                                                                  EXHIBIT 10.42C

                             STOCK OPTION AGREEMENT

     This Agreement is made as of the ____ day of _________200[0] by and
between Clean Harbors, Inc., a Massachusetts corporation (the "Company"), and
[__________________] ("Optionee").

     WHEREAS, Optionee is a valuable and trusted Non-Employee Director of the
Company;

     WHEREAS, Section 7 of the Clean Harbors, Inc. 2000 Stock Incentive Plan
approved by the stockholders of the Company on June 16, 2000 (the "Plan")
provides for the awarding of Non-Discretionary Options to Non-Employee Directors
elected to serve on the Board of Directors of the Company;

     WHEREAS, Optionee was elected to serve on the Board of Directors, for a
three year term, on [________________]; and

     WHEREAS, the provisions of the Plan are hereby incorporated in and made
part of this document by reference and, in particular, this Agreement shall in
all respects be subject to the conditions set forth in the Plan.

     NOW, THEREFORE, in consideration of the foregoing premises, it is agreed by
and between the Company and the Optionee as follows:

     1.   GRANT OF OPTION. Subject to and upon the terms and conditions of this
Agreement, the Company hereby grants to Optionee the right, privilege and option
to purchase ____________shares ("Option Shares") of Stock at the purchase price
of $__________ per share.

     2.   TIME OF EXERCISE OF OPTION/VESTING. This option may be exercised as to
_________ Option Shares immediately and as to an additional _________ Option
Shares upon each anniversary of the date of this grant, so that this option may
be exercised as to one hundred (100%) percent of the total number of Option
Shares on and after the ________ anniversary of the date hereof.

     3.   METHOD EXERCISE. This option may be exercised by written notice
directed to the Stock Option Committee of the Board of Directors (the
"Committee") or its designated representative at the Company's principal place
of business, specifying the number of Option Shares to be purchased and
accompanied by a check in payment of the option price for the number of such
Shares specified. The Company shall make immediate delivery of such Shares;
provided, however, that if any law or regulation requires the Company to take
any action with respect to the Shares specified in such notice or if the
Committee deems it desirable to take such action as a condition to or in
connection with the sale or purchase of stock under the Plan before the issuance
thereof, then the date of delivery of such Shares shall be extended for the
period necessary to take such action. In no event shall this option be exercised
unless there is in effect

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with respect to the Shares being purchased a registration statement under the
Securities Act of 1933, as amended (the "Act"), or unless the Company shall have
received a written opinion of counsel for or approved by the Company that the
issuance of such Shares is exempt under the Act and any applicable state
securities laws. If the Company shall then have in effect arrangements with a
brokerage firm for optionees to exercise options without payment, or so called
"cashless" option exercises, and the Optionee shall elect such method of
exercise, the Optionee shall comply with the Company's requirements and
procedures for such exercise.

     4.   TERMINATION OF OPTION. Except as herein otherwise stated or as
otherwise determined by the Committee, this option, to the extent not previously
exercised, shall terminate upon the first to occur of the following dates:

     (a)  except as provided in clause (b) below, the expiration of three (3)
months after the date on which Optionee shall cease to serve as a director of
the Company unless such;

     (b)  the expiration of twelve (12) months after the date of death of
Optionee; provided, however, that the person or persons to whom this option is
transferred by will or by the laws of descent and distribution may, at any time
within such one year period exercise this option to the extent Optionee would
have been entitled to do so on the date of exercise of the option. This option
or any portion owned by Optionee upon the date of Optionee's death not so
exercised shall terminate; and

     (c)  the expiration of five (5) years from the grant of this option.

     5.   RECLASSIFICATION, CONSOLIDATION OR MERGER. If and to the extent that
the number of issued shares of Stock of the Company shall be increased or
reduced by change in par value, split up, reclassification, distribution of a
dividend payable in stock, or the like, the number of Shares subject to this
option and the option price per share shall be proportionately adjusted. If the
Company is reorganized or consolidated or merged with another corporation,
Optionee shall be entitled to receive options covering shares of such
reorganized, consolidated, or merged company in the same portion, at an
equivalent price, and subject to the same conditions as set forth herein. For
purposes of the preceding sentence, the excess of the aggregate fair market
value of the Shares subject to this option immediately after the reorganization,
consolidation, or merger over the aggregate option price of such Shares shall be
the same as aggregate fair market value of all Shares subject to the option
immediately before such reorganization, consolidation, or merger over the
aggregate option price of such Shares, and the new option or assumption of the
old option shall not give Optionee additional benefits which Optionee did not
have under the old option, or deprive Optionee of benefits which Optionee had
under the old option.

     6.   CHANGE OF CONTROL. Notwithstanding the provisions of Section 2 above,
to the extent not previously exercised or terminated under the provision of
Section 4 above and to the extent that Section 2 above does not provide for the
exercise of this option as to one hundred (100%) percent of the total number of
Option Shares immediately, this option may be exercised with respect to one
hundred (100%) percent of the total number of Option Shares remaining hereunder
in the event of the occurrence of a Change of Control of the Company. A Change
of Control of the Company shall be deemed to have occurred if the Company is a
party to any

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merger, consolidation or sale of assets, or there is a tender offer for the
Company's common stock, or a contested election of the Company's directors, and
as a result of any such event, either (i) the directors of the Company in office
immediately before such event cease to constitute a majority of the Board of
Directors of the Company, or of the company succeeding to the Company's
business, or (ii) any company, person or entity (including one or more persons
and/or entities acting in concert as a group) other than an affiliate of the
Company gains "control" (ownership of more than fifty (50%) percent of the
outstanding voting stock of the Company) over the Company. The concept of
"control" shall be deemed to mean the direct or indirect ownership, beneficially
or of record, of voting stock of the Company. An "affiliate" shall be defined as
any person or entity which controls more than fifty (50%) percent of the Company
or is more than fifty (50%) percent controlled by the Company or by any other
person or entity which controls more than fifty (50%) percent of the Company.
Upon the exercise of this option prior to its termination and subsequent to a
Change of Control, the Optionee shall be entitled to receive the cash,
securities or other consideration he would have been entitled to receive had he
been entitled to exercise, and had he exercised, this option immediately prior
to such Change of Control.

     Notwithstanding the foregoing, this Change of Control provision shall not
apply unless the Optionee shall have received an opinion from Company counsel
that the effectiveness of this Section 6 shall not disqualify the Optionee's
status as a "disinterested director" under Rule 16b-3(c)(2)(i) issued by the
Securities and Exchange Commission under Section 16 of the Securities and
Exchange Act of 1934 (the "Exchange Act") as then in effect.

     7.   RIGHTS PRIOR TO EXERCISE OF OPTION. This option is nontransferable by
Optionee, except in the event of death as provided in subparagraph 4(b) above,
and during lifetime is exercisable only by Optionee. Optionee shall have no
rights as a stockholder with respect to the Option Shares until payment of the
option price and delivery to Optionee of such shares as herein provided.

     8.   RESTRICTION ON SALE OF OPTION SHARES. If and to the extent that this
option shall, according to its terms, be exercisable as to any of the Option
Shares within six (6) months from the date hereof, such Option Shares may not be
sold for a period of six (6) months from the date hereof.

     9.   RULE 16B-3. To the extent that any provision of this Agreement shall
fail to comply with all applicable provisions of Rule 16b-3 issued by the
Securities and Exchange Commission under Section 16 of the Exchange Act, such
provision shall be deemed null and void.

     10.  BINDING EFFECT. This Agreement shall inure to the benefit of and be
binding upon the parties hereto and upon their respective heirs, executors,
administrators, successors, and assigns.

     11.  GOVERNING LAW. This Agreement shall be construed and governed in
accordance with the laws of the Commonwealth of Massachusetts.

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

                                        CLEAN HARBORS, INC.


                                        By:
--------------------------                 -----------------------------
[name of optionee]                            Its Chairman
Optionee/Director