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                            SCHEDULE 14A INFORMATION
          PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE SECURITIES
                              EXCHANGE ACT OF 1934
                             (AMENDMENT NO.      )
 
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     [ ] Preliminary proxy statement        [ ] Confidential, for Use of the
                                                Commission Only (as permitted by
                                                Rule 14a-6(e)(2))
 
     [ ] Definitive proxy statement
 
     [X] Definitive additional materials
 
     [ ] Soliciting material pursuant to Rule 14a-11(c) or Rule 14a-12
 
                               SAFETY-KLEEN CORP.
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                (Name of Registrant as Specified in Its Charter)
 
                      LAIDLAW ENVIRONMENTAL SERVICES, INC.
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    (Name of Person(s) Filing Proxy Statement, if other than the Registrant)
 
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0-11.
 
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pursuant to Exchange Act Rule 0-11 (Set forth the amount on which the filing fee
is calculated and state how it was determined):
 
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     [ ] Fee paid previously with preliminary materials.
 
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                 Laidlaw Environmental Announces Exchange Ratio


COLUMBIA, S.C., March 11 /PRNewswire/ -- Laidlaw Environmental Services, Inc.
(NYSE: LLE) said today that the exchange ratio for purposes of its exchange
offer for Safety-Kleen Corp. (NYSE: SK), which is scheduled to expire at
Midnight, New York City time, on March 16, 1998, will be 2.8 LLE common shares
for each SK common share validly tendered and not withdrawn, in addition to the
$18.00 per share Safety-Kleen shareholders will be entitled to receive in cash.
Should the LLE offer be extended, the exchange ratio will be recalculated as
described in the Amended Prospectus.

Laidlaw Environmental Services, Inc., headquartered in Columbia, South Carolina,
supplies hazardous and industrial waste management services to industry and
government across North America. The Company provides customers with local
service from more than 100 locations in the United States and Canada.



SOURCE Laidlaw Environmental Services, Inc.

CONTACT: Kenneth W. Winger, President and Chief Executive Officer, or Paul R.
Humphreys, Senior Vice President, Finance and Chief Financial Officer, Laidlaw
Environmental Services, Inc., 803-933-4210