EX-10.S
                              AMENDED EMPLOYMENT AGREEMENT





June 4, 2002

Larry W. Singleton
Safety-Kleen Corp.
1301 Gervais Street, Suite 300
Columbia, SC  29201

Dear Larry,

As you know,  your  employment  contract  expires July 16, 2002. You have served
Safety-Kleen Corp. (the "Company") for the last two years as the Chief Financial
Officer,  and I  understand  that you are  willing to  continue to serve in that
capacity.  The  Company  would also like you to continue  as an  Executive  Vice
President and Chief Financial Officer.  Accordingly,  the purpose of this letter
is to amend the Employment  Agreement by and between you (the  "Executive")  and
the Company, dated July 17, 2000 (the "Singleton Employment Agreement"):

1.       Paragraph  1 of the  Singleton  Employment  Agreement  is  deleted  and
         replaced as follows:

         "The term of the  Employment  Agreement  (the "Term") shall end May 31,
         2003,  unless such  employment is earlier  terminated for any reason as
         provided in the Employment Agreement, as amended."

2.       Paragraph  2(a) of the  Singleton  Employment  Agreement  is amended to
         reflect that  Executive's  title has changed from Senior Vice President
         and Chief  Financial  Officer to  Executive  Vice  President  and Chief
         Financial Officer.

3.       Paragraph 2(a)(2) of the Singleton Employment Agreement is deleted.

4.       Paragraph  3 of the  Singleton  Employment  Agreement  is  deleted  and
         replaced as follows:

         "COMPENSATION.  (a) Salary. From the date of employment through the end
         of the  Term,  the  Executive  shall  receive  a  monthly  salary  (the
         "Salary") of $50,000,  payable in accordance with the Company's  normal
         payroll practices for executives.

                  (b) SIGNING BONUS Upon execution of this Amendment,  Executive
         will be entitled to a $100,000 signing bonus.

                  (c) OTHER BENEFITS. In addition to the foregoing, during the
         Term: (i) the Executive shall be entitled to participate in the current
         and any future savings, retirement, fringe benefit, and any other
         benefit plans, practices, policies and programs of the Company on terms
         and conditions commensurate with Executive's position and level of
         responsibility with the Company, but in no event less than those
         applicable to peer executives; provided, however, the Executive shall
         not be entitled to participate in any general bonus or severance plans,
         practices, policies or programs of the Company (and provided further
         that nothing herein will prevent the Board from approving discretionary
         bonus plans for the Executive); and (ii) the Executive shall be
         entitled to four weeks of vacation, effective and vested immediately.
         Further, the Company will promptly reimburse Executive for all travel
         and other business expenses that Executive incurs in the course of the
         performance of his duties under this Agreement, including any commuting
         expenses to/from and living expenses in Columbia, SC, plus tax "gross
         up" thereon if any taxes based on income are applicable, in a manner
         commensurate with Executive's position and level of responsibility with
         the Company, but in no event less than those applicable to peer
         executives.

                  (d) For purposes of this Section 3, the Executive's peer
         executives shall be other senior executives employed by the Company."

5.       Paragraph 4 (1) of the Singleton  Employment  Agreement is  deleted and
replaced with section 4(b) of that Employment  Agreement between the Company and
Thomas W. Arnst  dated  October  4, 2001 and  attached  as exhibit  10(u) to the
Company's 10k filed with the SEC on November 29, 2001 (the  "Exhibit  Employment
Agreement").

6.       Paragraph 4(e) of the Exhibit Employment  greement is  added as section
4(5) to the Singleton Employment Agreement.

7.       Paragraph  5  of  the Singleton  Employment  Agreement is  deleted  and
Replaced with paragraph 5 of the Exhibit Employment Agreement.

8.       The references to David Kurtz, Esq. in paragraph 11(1) of the Singleton
 Employment Agreement are deleted and replaced with the name Jan Baker.

9.      Paragraph  7  of the  Exhibit  Employment  Agreement,  along  with   the
incorporated  by  reference  Exhibit A, is  added to  the  Singleton  Employment
Agreement as paragraph 12.

Unless otherwise noted above,  all other provisions of the Singleton  Employment
Agreement  remain valid and in effect.  If you agree to the above changes to the
Singleton Employment Agreement,  please signify by signing below. This amendment
becomes effective upon the date of your signature.

                                     Very truly yours,

                                        /s/ Ronald A. Rittenmeyer

                                     Ronald A. Rittenmeyer
                                     Chairman
                                     Safety-Kleen Corp.


Consented and Agreed to:

  /s/ Larry W. Singleton
----------------------------
Larry W. Singleton

Dated:
 June 4, 2002
-----------------------------