NOTICE:

             A DRAFT VERSION OF THE 1OQ WAS INADVERTENTLY FILED.

               THUS, THIS 10Q/A IS THE CORRECT VERSION OF OUR 10Q.

                PLEASE ACCEPT OUR APOLOGY FOR ANY INCONVENIENCE

<PAGE>

                                 UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 10-Q/A


 QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
                              EXCHANGE ACT OF 1934


                  For the Quarterly Period Ended May 31, 1999


                         Commission File Number 1-8368


                               SAFETY-KLEEN CORP.
                               -----------------
             (Exact name of registrant as specified in its charter)


            Delaware                                         51-0228924
-------------------------------                            ------------------
(State or other jurisdiction of                             (I.R.S. Employer
 incorporation or organization)                              Identification No.)


1301 Gervais Street Columbia, Suite 300, South Carolina                 29201
-------------------------------------------------------               ----------
                (Address of principal executive offices)              (Zip Code)

       (803) 933-4200 (Registrant's telephone number, including area code)
       --------------

   ---------------------------------------------------------------------------
   (Former name, address and former fiscal year, if changed since last report)

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Sections 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.

                            Yes   X     No ____
                                 ---

          The number of shares of the issuer's common stock outstanding as of
     July 13, 1999 was 88,926,299.



<PAGE>





                               SAFETY-KLEEN CORP.


                                      INDEX

<TABLE>
<CAPTION>
PART 1   FINANCIAL INFORMATION

<S>     <C>                                                                                                             <C>

Item 1   Financial Statements

         Consolidated Statements of Income for the Three and Nine Months Ended
                May 31, 1999 and 1998...................................................................................2

         Consolidated Statements of Comprehensive Income for the Three and Nine Months Ended
                May 31, 1999 and 1998...................................................................................3

         Consolidated Balance Sheets as of May 31, 1999 and August 31, 1998.............................................4

         Consolidated Statements of Cash Flows for the Nine Months Ended
                May 31, 1999 and 1998...................................................................................5

         Notes to  Consolidated Financial Statements....................................................................6

Item 2   Management's Discussion and Analysis of Financial Condition and Results of Operations.........................17


PART II  OTHER INFORMATION

Item 1   Legal Proceedings.............................................................................................25

Item 2   Changes In Securities and Use Of Proceeds.....................................................................27

Item 6   Exhibits and Reports on Form 8-K..............................................................................28


Signatures.............................................................................................................33

</TABLE>


                                       1
<PAGE>

<TABLE>
<CAPTION>

                               SAFETY-KLEEN CORP.
                        CONSOLIDATED STATEMENTS OF INCOME
                     ($ in thousands, except per share data)
                                   (Unaudited)

                                                                   Three Months Ended            Nine Months Ended
                                                                         May 31,                      May 31,
                                                                         -------                      -------
                                                                       1999       1998            1999        1998
                                                                       ----       ----            ----        ----
<S>                                                              <C>           <C>            <C>           <C>

Revenues.......................................................    $ 400,935   $ 365,705      $ 1,270,089   $ 750,472
                                                                   ---------   ---------      -----------   ---------

Expenses:

   Operating...................................................      244,390     244,033          811,289     513,138
   Depreciation and amortization...............................       33,272      31,108          104,245      55,927
   Selling, general and administrative.........................       33,162      35,037          100,402      74,273
   Restructuring and other charges.............................           --      65,831               --      65,831
                                                                 -----------   ---------      -----------   ---------
     Total expenses............................................      310,824     376,009        1,015,936     709,169
                                                                 -----------   ---------      -----------   ---------
Operating income (loss)........................................       90,111     (10,304)         254,153      41,303
Interest expense, net..........................................       40,460      29,804          127,143      58,050
Equity in earnings of associated company.......................        1,002          --            2,104          --
                                                                 -----------   ---------      -----------   ---------
Income (loss) before income tax expense (benefit)..............       50,653     (40,108)         129,114     (16,747)
Income tax expense (benefit)...................................       20,959     (15,837)          54,614      (6,282)
                                                                 -----------   ----------     -----------   ----------
Income (loss) before minority interest.........................       29,694     (24,271)          74,500     (10,465)
Minority interest, net of tax..................................           --         235            1,211         129
                                                                 -----------   ---------      -----------   ---------
Income (loss) before extraordinary item........................       29,694     (24,036)          75,711     (10,336)
Extraordinary item, net of applicable income tax...............           --     (11,283)              --     (11,283)
                                                                 -----------   ----------     -----------   ----------
Net income (loss)..............................................  $    29,694   $ (35,319)     $    75,711   $ (21,619)
                                                                 ===========   ==========     ===========   ==========

Basic income (loss) per share:

   Income (loss) before extraordinary item.....................  $     0.34    $   (0.34)      $     0.86    $  (0.19)
   Extraordinary item, net of applicable income tax............          --        (0.16)              --       (0.21)
                                                                 -----------   ---------      -----------   ---------
   Net income (loss)...........................................  $     0.34    $   (0.50)      $     0.86    $  (0.40)
                                                                 ==========    =========       ==========    =========
   Weighted average common stock outstanding (000s)............      88,469       70,233           88,233      53,756
                                                                 ===========   =========      ===========    =========

Diluted income (loss) per share:

   Income (loss) before extraordinary item.....................  $     0.30    $   (0.34)      $     0.76    $  (0.19)
   Extraordinary item, net of applicable income tax............          --        (0.16)              --       (0.21)
                                                                 -----------   ---------      -----------    ---------
   Net income (loss)...........................................  $     0.30    $   (0.50)      $     0.76    $  (0.40)
                                                                 ==========    =========       ==========    =========
   Weighted average common stock outstanding and
     assumed conversions (000s)................................     111,835       70,233          111,610      53,756
                                                                 ===========   =========      ===========    =========

</TABLE>


           See accompanying Notes to Consolidated Financial Statements




                                       2
<PAGE>



<TABLE>
<CAPTION>

                                                 SAFETY-KLEEN CORP.
                                   CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
                                                  ($ in thousands)
                                                     (Unaudited)

                                                                     Three Months Ended           Nine Months Ended
                                                                         May 31,                       May 31,
                                                                         -------                       -------
                                                                       1999        1998            1999        1998
                                                                       ----        ----            ----        ----
<S>                                                              <C>           <C>            <C>           <C>

Net income (loss)..............................................  $    29,694   $ (35,319)     $    75,711   $ (21,619)
Other comprehensive income, net of tax:
   Unrealized foreign currency translation adjustment..........        3,358      (1,697)           3,294      (3,962)
   Unrealized gain on securities available for sale, net
     of tax of $1,247..........................................           --      (1,870)              --          --
                                                                 -----------   ----------     -----------   ---------
Other comprehensive income.....................................        3,358      (3,567)           3,294      (3,962)
                                                                 -----------   -----------    -----------   ----------
Comprehensive income (loss)....................................  $    33,052   $ (38,886)     $    79,005   $ (25,581)
                                                                 ===========   ==========     ===========   ==========
</TABLE>


           See accompanying Notes to Consolidated Financial Statements




                                       3
<PAGE>



<TABLE>
<CAPTION>

                               SAFETY-KLEEN CORP.
                           CONSOLIDATED BALANCE SHEETS
                                ($ in thousands)

                                                                                     MAY 31, 1999
                                                                                     (UNAUDITED)          AUGUST 31, 1998
                                                                                     -----------          ---------------
<S>                                                                              <C>                <C>

ASSETS

   Current assets

     Cash and cash equivalents............................................       $      10,320      $      16,333
     Trade and other accounts receivable, net of allowance................             362,145            320,048
     Inventories and supplies.............................................              61,290             53,759
     Deferred income taxes................................................              72,368             69,426
     Income taxes recoverable.............................................                  --             37,495
     Other current assets.................................................              71,281             53,750
                                                                                 -------------      -------------
       Total current assets...............................................             577,404            550,811
   Long-term investments..................................................             295,563             35,926
   Property, plant and equipment, net.....................................           2,532,978          2,850,502
   Goodwill, net of amortization..........................................           1,110,717          1,023,154
   Other assets...........................................................              16,882             16,979
                                                                                 -------------      -------------
     Total assets.........................................................       $   4,533,544      $   4,477,372
                                                                                 =============      =============

LIABILITIES

   Current liabilities

     Accounts payable.....................................................       $     151,486      $     128,560
     Accrued liabilities..................................................             184,390            219,352
     Current portion of long-term debt....................................              78,680             77,004
                                                                                 -------------      -------------
       Total current liabilities..........................................             414,556            424,916
   Environmental and other long-term liabilities..........................             258,637            259,459
   Long-term debt.........................................................           1,907,988          1,853,164
   Subordinated convertible debenture.....................................             350,000            350,000
   Deferred income taxes..................................................             491,025            575,127
                                                                                 -------------      -------------
     Total liabilities....................................................           3,422,206          3,462,666
                                                                                 -------------      -------------

   Commitments and contingencies..........................................                  --                 --
                                                                                 -------------      -------------

STOCKHOLDERS' EQUITY

   Common stock, par value $1.00 per share; authorized  250,000,000;
    issued and outstanding 88,923,674 - May 31, 1999; 87,746,243 -
    August 31, 1998.......................................................              88,924             87,746
   Additional paid-in capital.............................................           1,198,996          1,182,547
   Accumulated other comprehensive income.................................             (15,534)           (18,828)
   Accumulated deficit....................................................            (161,048)          (236,759)
                                                                                 --------------     --------------
     Total stockholders' equity...........................................           1,111,338          1,014,706
                                                                                 -------------      -------------
     Total liabilities and stockholders' equity...........................       $   4,533,544      $   4,477,372
                                                                                 =============      =============
</TABLE>


           See accompanying Notes to Consolidated Financial Statements




                                       4
<PAGE>



<TABLE>
<CAPTION>
                                                 SAFETY-KLEEN CORP.
                                        CONSOLIDATED STATEMENTS OF CASH FLOWS
                                                  ($ in thousands)
                                                     (Unaudited)

                                                                                            Nine Months Ended
                                                                                                 May 31,
                                                                                                 -----
                                                                                         1999             1998
                                                                                         ----             ----

<S>                                                                              <C>    <C>

Cash flows from operating activities:

   Net income (loss)                                                             $      75,711     $     (21,619)
   Adjustments to reconcile net income (loss) to net cash provided
     by operations:

       Extraordinary item, net of applicable income tax                                     --            11,283
       Restructuring and other charges, net of applicable income tax                        --            39,499
       Depreciation and amortization                                                   104,245            55,927
       Deferred income taxes                                                            33,524             7,816
       Change in working capital and other items                                       (55,001)          (18,142)
       Decrease in liabilities assumed upon acquisition                                (67,395)          (19,830)
                                                                                 --------------    --------------
Net cash provided by operating activities                                               91,084            54,934
                                                                                 -------------     -------------

Cash flows from investing activities:

   Cash expended on business acquisitions                                               (9,796)      (1,282,744)
   Proceeds from sale of business                                                      138,617            33,675
   Purchases of property, plant and equipment                                          (48,875)          (34,564)
   Increase in long-term investments                                                  (219,375)               --
   Change in other, net                                                                   (478)            7,539
                                                                                 --------------    -------------
Net cash used in investing activities                                                 (139,907)       (1,276,094)
                                                                                 --------------    --------------

Cash flows from financing activities:

   Issuance of common stock on exercise of stock options                                    34               436
   Bank financing fees and expenses                                                     (9,425)          (36,946)
   Net repayments of long-term debt                                                   (167,838)         (591,547)
   Issuance of long-term debt                                                          225,000         1,857,756
                                                                                 -------------     -------------
Net cash provided by financing activities                                               47,771         1,229,699
                                                                                 -------------     -------------

Effect of exchange rate changes on cash                                                 (4,961)             (202)
                                                                                 --------------    --------------

Net increase (decrease) in cash and cash equivalents                                    (6,013)            8,337
Cash and cash equivalents at:
   Beginning of period                                                                  16,333            11,160
                                                                                 -------------     -------------
   End of period                                                                 $      10,320     $      19,497
                                                                                 =============     =============

</TABLE>



           See accompanying Notes to Consolidated Financial Statements




                                       5
<PAGE>




                               SAFETY-KLEEN CORP.
                   Notes to Consolidated Financial Statements
                     For the Nine Months Ended May 31, 1999

NOTE 1 - BASIS OF PRESENTATION

The accompanying  unaudited interim consolidated  financial statements have been
prepared  in  accordance  with the  instructions  to Form 10-Q and Rule 10-01 of
Regulation S-X and, therefore, do not include all of the disclosures required by
generally accepted accounting principles for annual financial statements. In the
opinion  of  management,   all  adjustments  considered  necessary  for  a  fair
presentation  of the  interim  period  results  have  been  included;  all  such
adjustments are of a normal recurring  nature.  Operating  results for the three
and nine months ended May 31, 1999 are not necessarily indicative of the results
that may be expected  for the full fiscal year  ending  August 31,  1999.  These
statements  should  be read  in  conjunction  with  the  consolidated  financial
statements, including the accounting policies, and notes thereto included in the
Registrant's  Annual Report on Form 10-K, filed with the Securities and Exchange
Commission on October 29, 1998.  Certain amounts as of August 31, 1998 have been
reclassified to conform to the current period's presentations.

In June 1997, the Financial Accounting Standards Board ("FASB") issued Statement
No. 130,  "Reporting  Comprehensive  Income"  ("SFAS  130").  This  standard was
adopted by the Company for the fiscal year beginning September 1, 1998. SFAS 130
establishes standards for reporting and displaying  comprehensive income and its
components.  Comprehensive  income is defined  as the change in equity  during a
period from  transactions  and other  events and  circumstances  from  non-owner
sources  and  includes  all  changes  in  equity  during a period  except  those
resulting from  investments by and  distributions  to owners.  All prior periods
presented have been restated.

NOTE 2 - SHAREHOLDER MATTERS

At the annual meeting of  shareholders  held on November 24, 1998,  shareholders
approved the change in the Company's name from Laidlaw  Environmental  Services,
Inc. to Safety-Kleen Corp.

In addition, the shareholders approved a one-for-four reverse stock split, which
became  effective at the close of business on November  30, 1998.  For each four
shares of Safety-Kleen  common stock, one share of new Safety-Kleen common stock
was issued.  In connection  with the reverse  stock split,  the number of common
shares available for issuance was reduced from 750 million to 250 million.  As a
result,  prior period shares issued and  outstanding,  weighted  average  common
stock  outstanding  and basic and diluted income per share have been restated to
reflect the reverse stock split.

NOTE 3 - CHANGES IN LONG-TERM DEBT

The Company has entered into an agreement  with Laidlaw Inc. to  repurchase  the
$350 million pay-in-kind  convertible  subordinated  debenture ("PIK Debenture")
which was issued to Laidlaw in May, 1997 in connection  with the  acquisition of
Rollins  Environmental  Services,  Inc.  Subject


                                       6
<PAGE>

to stockholder  approval of the issuance of common stock in connection  with the
repurchase, the aggregate  purchase  price will  consist of (i) $200  million in
cash, (ii) 11,320,755  shares of common stock and (iii) cash or shares of common
stock in an amount equal to any accrued and unpaid interest on the PIK Debenture
to the date of repurchase.

On May 17, 1999,  the Company  issued $225  million  9.25% Senior Notes due 2009
(the "Notes") in a Rule 144A offering.  Net proceeds from the sale of the Notes,
after the underwriting  discount and other expenses,  were approximately $214
million.  The proceeds  will be used to finance the cash portion of the purchase
price for the  repurchase  of the PIK  Debenture,  for expenses  relating to the
repurchase and for general corporate purposes. The Notes mature on May 15, 2009.
Interest on the Notes will be payable semiannually commencing November 15, 1999.
The Notes will be redeemable, in whole or in part, at the option of the Company,
at any time prior to May 15, 2004 at a redemption  price equal to the greater of
(i) 100% of the  principal  amount of such Notes or (ii) the sum of the  present
values of  104.625%  of the  principal  amount of such  Notes and the  scheduled
payments of interest  thereon through and including May 15, 2004,  discounted to
such redemption date on a semi-annual  basis at the adjusted  treasury rate plus
50 basis points,  together with accrued and unpaid  interest,  if any. The Notes
will be  redeemable,  in whole or in part,  at the option of the  Company at any
time  on or after May 15, 2004 at  104.625% of the  principal  amount  declining
ratably in annual increments to par on or after May 15, 2007. In addition, prior
to  May 15, 2002, the  Company may redeem  up to 35% of the  original  aggregate
principal amount of the Notes with the net proceeds of one or more public equity
offerings  at a  redemption  price  equal to  109.25%  of the  principal  amount
thereof,  plus  accrued  and  unpaid  interest.  Upon a change in control of the
Company, each holder of the Notes may require the Company to repurchase all or a
portion of such holder's  Notes at 101% of the principal  amount  thereof,  plus
accrued interest.

The  Company is required  to redeem the Notes for 101% of the  principal  amount
plus accrued and unpaid interest, if any, if the repurchase of the PIK Debenture
is not completed by September  30, 1999.  The net proceeds of the Notes are held
in escrow to fund, if necessary,  the special mandatory  redemption.  The escrow
fund has been included in long-term investments at May 31, 1999.

The Notes are  unsecured  and rank equally  with all existing and future  senior
indebtedness  and senior to all existing and future  subordinated  indebtedness.
The Notes are not guaranteed by the Company's subsidiaries.

The Notes contain certain  covenants  that, in certain  instances and subject to
certain  limitations and qualifications,  restrict,  among other things, (i) the
incurrence  of  additional  debt;  (ii) the  incurrence  of  certain  contingent
obligations;  (iii) dividends and other payments;  (iv) the issuance of stock of
subsidiaries;  (v) certain  investments;  (vi) certain liens; (vii) transactions
with affiliates; and (viii) certain consolidations, mergers or sales of assets.

In accordance with a Registration  Rights Agreement  entered into at the time of
the issuance of the Notes,  the Company filed a registration  statement with the
Securities and Exchange Commission on  July 12, 1999, pursuant to which
the Company  proposes to exchange the Notes for registered  notes of the Company
with terms identical to the Notes.


                                       7
<PAGE>

NOTE 4 - COMMITMENTS AND CONTINGENCIES

Legal Proceedings:

TAX MATTERS: On March 1, 1999, Laidlaw Inc.  ("Laidlaw")  announced a settlement
of a dispute between  Laidlaw's United States  subsidiaries and the Commissioner
of Internal Revenue relating to the timing and deductibility for tax purposes of
interest attributable to loans owing to related foreign persons during the years
from 1986 to 1994.

The total net after tax cash cost to Laidlaw will be approximately $226 million.
The payment includes  approximately $121 million in taxes together with interest
of approximately $161 million ($105 million after tax).

This settlement  resolves  matters in the United States Tax Court  (captioned as
Laidlaw Transportation, Inc. and Subsidiaries et. al v. Commissioner of Internal
Revenue,  Docket Nos.  9361-94 and 9362-94)  relating to the 1986 to 1991 fiscal
years as well as claims  raised in a thirty day letter  relating  to the 1992 to
1994 fiscal years.  The  Commissioner  of Internal  Revenue had asserted  claims
totaling approximately $500 million.

Pursuant to the agreement dated February 6, 1997 among the Company,  Laidlaw and
Laidlaw  Transportation,  Inc. ("LTI"),  Laidlaw and LTI are responsible for any
tax  liabilities  resulting  from these  matters.  Based upon  discussions  with
Laidlaw,  the  Company's  income tax provision  determined on a separate  return
basis during the period audited by the Internal  Revenue  Service was sufficient
and no  additional  taxes or interest  are due to or from Laidlaw as a result of
the settlement.

NOTE 5 - EUROPEAN OPERATIONS

On December 23, 1998, the Company announced the recapitalization of its European
operations  resulting  in the sale of 56% of the  Company's  equity  interest in
those operations. As a result of the recapitalization,  the Company will receive
gross  proceeds  totaling  $154.0  million  (of which  $138.6  million  has been
received as of May 31, 1999),  which will be used to pay down  borrowings  under
the revolver tranche of the Senior Credit Facility.  The transaction resulted in
no gain or loss.

Effective December 1, 1998, the Company ceased to consolidate the results of the
European  operations  and began to  account  for the  investment  by the  equity
method.

NOTE 6 - PURCHASE PRICE ALLOCATION

The  acquisition  of the  former  Safety-Kleen  Corp.  in  fiscal  year 1998 was
accounted for under the purchase method. The purchase price was allocated to the
assets acquired and liabilities assumed based upon management's best estimate of
their  fair  value  at the time of the  acquisition.  The  areas  of  particular
complexity   included  the   valuation  of  long-lived   assets,   environmental
liabilities,   pre-acquisition   contingencies  and  the  related  deferred  tax
consequences.  The  determination  of the fair  value of  these  items  has been
completed  and,  as  a  result,   the  purchase


                                       8
<PAGE>

price has been increased by approximately $85 million.  The adjustment  consists
of a $52 million  decrease in the fair value of fixed assets based  primarily on
completed appraisals, an additional liability of $20 million associated with the
termination of the Old Safety-Kleen  defined benefit pension plan, a $35 million
adjustment  to  environmental  and  other  liabilities  based  on the  Company's
evaluation and analysis of facts and information that existed at the acquisition
date and obtained prior to the end of the allocation  period,  and a $22 million
decrease in the deferred tax liability.

The purchase  price has been  allocated to the assets  acquired and  liabilities
assumed based on the fair values at the date of acquisition as follows:

Current assets................................   $      231,351
Property, plant and equipment.................        1,705,314
Goodwill......................................        1,033,077
Other assets..................................           14,680
Current liabilities...........................         (119,927)
Deferred income taxes.........................         (448,810)
Other deferred items..........................         (182,584)
Long-term debt................................         (217,858)
                                                 ---------------
     Total purchase price.....................   $    2,015,243
                                                 ==============


NOTE 7 - STOCKHOLDERS' EQUITY

Changes in the components of  stockholders'  equity,  restated for the effect of
the one-for-four  reverse stock split, since September 1, 1998 are as follows ($
in thousands):

<TABLE>
<CAPTION>

                                                                       Accumulated
                                                      Additional          Other                              Total
                                        Common         Paid-In        Comprehensive      Accumulated      Stockholders'
                                        Stock          Capital           Income            Deficit           Equity
                                        -----          -------           ------            -------           ------
<S>                                  <C>             <C>              <C>               <C>               <C>

Balance, September 1, 1998           $    87,746     $  1,182,547     $    (18,828)     $   (236,759)     $   1,014,706
Net income for period                         --               --               --            75,711             75,711
Issuance of shares (Note A)                1,178           16,449               --                --             17,627
Cumulative foreign currency.......
   translation adjustment                     --               --            3,294                --              3,294
                                     -----------     ------------     ------------      -----------       -------------
Balance, May 31, 1999                $    88,924     $  1,198,996     $    (15,534)     $   (161,048)     $   1,111,338
                                     ===========     ============     =============     =============     =============

</TABLE>

Note A:  Includes  1,168,541  shares issued to satisfy the November 15, 1998 and
May 15, 1999 interest payments due on the subordinated convertible debenture.


                                       9
<PAGE>

NOTE 8 - STATEMENTS OF CASH FLOWS

The non-cash transactions for the nine months ended May 31, 1999 and 1998 are as
follows ($ in thousands):

<TABLE>
<CAPTION>

                                                                                 Nine Months Ended
                                                                                       May 31,
                                                                                       -------
                                                                              1999               1998
                                                                              ----               ----
<S>                                                                         <C>           <C>

Non-cash investing and financing activities:
   Business combinations:

     Fair value of assets acquired.....................................     $    --       $   2,869,192
     Fair value of liabilities acquired................................          --             930,202
     Less, cash paid                                                             --          (1,252,341)
     Fair value of stock issued on acquisition.........................          --             686,649
   Issuance of common stock to satisfy interest payment due on

     subordinated convertible debenture................................      17,500              17,500
   Issuance of common stock to satisfy payment of directors' fees......          93                  --
   Non-cash transactions arising from sale of business:

     Promissory note receivable........................................          --               8,000
     Reduction of debt.................................................          --              40,814

</TABLE>


NOTE 9 - SUMMARIZED FINANCIAL INFORMATION

The Senior  Subordinated  Notes (the "Notes") issued by  Safety-Kleen  Services,
Inc.,  a  consolidated  subsidiary  of the  Company,  are jointly and  severally
guaranteed by Safety-Kleen Corp. and all wholly-owned  domestic  subsidiaries of
the  Company  on a full and  unconditional  basis.  The  Notes  contain  certain
covenants,  which,  among other things,  restrict the payment of dividends  from
Safety-Kleen Services,  Inc. and its subsidiary guarantors to Safety-Kleen Corp.
Summarized  financial  information for each of Safety-Kleen Corp.,  Safety-Kleen
Services, Inc., the subsidiary guarantors,  and the subsidiary non-guarantors on
a consolidating  basis are presented below.  Separate  financial  statements and
other disclosures  concerning the subsidiary guarantors are not included because
management believes that they are not material to investors.




                                       10
<PAGE>


<TABLE>
<CAPTION>


                      Consolidating Condensed Balance Sheet
                                  May 31, 1999
                                   (Unaudited)

                                           Safety-Kleen                Subsidiary
                             Safety-Kleen    Services,   Subsidiary       Non-       Elimination    Consolidated
($ in thousands)                 Corp.         Inc.      Guarantors    Guarantors      Entries         Totals
                                 -----         ----      ----------    ----------      -------         ------
ASSETS
<S>                          <C>           <C>           <C>           <C>           <C>            <C>

Current assets ...........   $       546   $        --   $   530,183   $    46,675   $        --    $   577,404
Property, plant and
   equipment, net ........            --            --     2,341,408       191,570            --      2,532,978
Investment in subsidiaries     1,586,032     2,731,453     1,681,569         5,495    (6,004,549)            --
Goodwill .................          --              --     1,055,000        55,717            --      1,110,717
Other non-current assets..       219,375            --        91,692         1,378            --        312,445
                             -----------   -----------   -----------   -----------   -----------    -----------
   Total assets ..........   $ 1,805,953   $ 2,731,453   $ 5,699,852   $   300,835   $(6,004,549)   $ 4,533,544
                             ===========   ===========   ===========   ===========   ===========    ===========

LIABILITIES

Current liabilities ......   $     5,415   $    88,883   $   285,134   $    35,124   $        --    $   414,556
Non-current liabilities ..            --            --       742,439         7,223            --        749,662
Long-term debt ...........       339,200     1,507,981        15,932        44,875            --      1,907,988
Subordinated convertible
   debenture .............       350,000            --            --            --            --        350,000
                             -----------   -----------   -----------   -----------   -----------    -----------
   Total liabilities .....       694,615     1,596,864     1,043,505        87,222            --      3,422,206

STOCKHOLDERS'  EQUITY ....     1,111,338     1,134,589     4,656,347       213,613    (6,004,549)     1,111,338
                             -----------   -----------   -----------   -----------   -----------    -----------
Total liabilities and

   stockholders' equity ..   $ 1,805,953   $ 2,731,453   $ 5,699,852   $   300,835   $(6,004,549)   $ 4,533,544
                             ===========   ===========   ===========   ===========   ===========    ===========

</TABLE>

<TABLE>
<CAPTION>

                   Consolidating Condensed Statement of Income
                         Three Months Ended May 31, 1999
                                   (Unaudited)

                                         Safety-Kleen                Subsidiary
                             Safety-Kleen  Services,    Subsidiary      Non-        Elimination  Consolidated
($ in thousands)                 Corp.       Inc.       Guarantors   Guarantors       Entries       Totals
                                 -----       ----       ----------   ----------      -------        ------
<S>                            <C>         <C>           <C>          <C>             <C>          <C>

Total revenues .............   $     --    $     --      $355,591     $ 49,221        $ (3,877)    $400,935
Operating expenses .........        136          --       279,875       34,690          (3,877)     310,824
                               --------    --------      --------     --------        --------     --------
Operating income (loss) ....       (136)         --        75,716       14,531              --       90,111
Interest expense, net ......      6,527      29,901         2,322        1,710              --       40,460
Equity in undistributed
   earnings of subsidiaries      33,687      51,701         1,002           --         (85,388)       1,002
                               --------    --------      --------     --------        --------     --------
Income before income

   tax expense (benefit) ...     27,024      21,800        74,396       12,821         (85,388)      50,653
Income tax expense (benefit)     (2,670)    (11,887)       29,929        5,587              --       20,959
                               --------    --------      --------     --------        --------     --------
Net income .................   $ 29,694    $ 33,687      $ 44,467     $  7,234        $(85,388)    $ 29,694
                               ========    ========      ========     ========        ========     ========

</TABLE>





                                       11
<PAGE>



<TABLE>
<CAPTION>

                   Consolidating Condensed Statement of Income
                         Nine Months Ended May 31, 1999
                                   (Unaudited)

                                              Safety-Kleen                    Subsidiary
                                Safety-Kleen    Services,       Subsidiary        Non-       Elimination     Consolidated
($ in thousands)                   Corp.          Inc.          Guarantors     Guarantors      Entries          Totals
                                   -----          ----          ----------     ----------      -------          ------
<S>                              <C>            <C>            <C>             <C>           <C>             <C>

Total revenues .............     $      --      $      --      $ 1,069,289     $ 213,382     $   (12,582)    $ 1,270,089
Operating expenses .........           136             --          875,134       153,248         (12,582)      1,015,936
                                 ---------      ---------      -----------     ---------     ------------    -----------
Operating income (loss) ....          (136)           --           194,155        60,134              --         254,153
Interest expense, net ......        19,354        100,120            5,920         1,749              --         127,143
Equity in undistributed
   earnings of subsidiaries         87,111        145,671            2,104            --        (232,782)         2,104
                                 ---------      ---------      -----------     ---------     ------------    -----------
Income before income

   tax expense (benefit) ...        67,621         45,551          190,339        58,385        (232,782)        129,114
Income tax expense (benefit)        (8,090)       (41,560)          79,010        25,254              --          54,614
                                 ---------      ---------      -----------     ---------     ------------    -----------
Income before minority

   interest ................        75,711         87,111          111,329        33,131        (232,782)        74,500
Minority interest ..........            --             --              176         1,035              --          1,211
                                 ---------      ---------      -----------     ---------     ------------    -----------
Net income .................     $  75,711      $  87,111      $   111,505     $  34,166     $  (232,782)    $   75,711
                                 =========      =========      ===========     =========     ============    ===========

</TABLE>





                                       12
<PAGE>


<TABLE>
<CAPTION>


                 Consolidating Condensed Statement of Cash Flows
                         Nine Months Ended May 31, 1999
                                   (Unaudited)

                                                Safety-Kleen                   Subsidiary
                                  Safety-Kleen    Services,     Subsidiary        Non-       Elimination     Consolidated
($ in thousands)                      Corp.         Inc.        Guarantors     Guarantors      Entries          Totals
                                      -----         ----        ----------     ----------      -------          ------
<S>                                <C>          <C>             <C>         <C>    <C>    <C>

Net cash provided by (used in)
   operating activities ......     $   (5,795)   $  (94,105)    $  173,724     $   17,260    $        --     $     91,084
                                   -----------   -----------    -----------    -----------   -----------     ------------
Cash flows from investing
   activities:
Cash expended on

   acquisition of business ...             --            --         (9,694)          (102)            --           (9,796)
Proceeds from sale of business             --            --        138,617             --             --          138,617
Purchases of property, plant
   and equipment .............             --            --        (42,479)        (6,396)            --          (48,875)
Increase in long-term
   investments ...............       (219,375)           --             --             --             --         (219,375)
Change in other, net .........             --            --           (604)           126             --             (478)
                                   -----------   ----------     -----------    -----------   -----------     ------------
Net cash provided by (used in)

   investing activities ......       (219,375)           --         85,840         (6,372)            --         (139,907)
                                   -----------   ----------     ----------     -----------   -----------     ------------
Cash flows from financing
   activities:
Issuance of common stock on

   exercise of stock options..             34            --             --             --             --               34
Borrowings of long-term debt..        225,000            --             --             --             --          225,000
Repayment of long-term debt ..             --      (158,983)          (918)        (7,937)            --         (167,838)
Bank financing fees ..........         (9,179)         (246)            --             --             --           (9,425)
Intercompany payable
   (receivable) ..............          9,315       253,334       (253,307)        (9,342)            --               --
                                   -----------   -----------    -----------    -----------   -----------     ------------
Net cash provided by (used in)
   financing activities ......        225,170        94,105       (254,225)       (17,279)            --           47,771
                                   -----------   -----------    -----------    -----------   -----------     ------------
Effect of exchange rate
   changes on cash ...........             --            --             --         (4,961)            --           (4,961)
                                   -----------   -----------    -----------    -----------   -----------     -------------
Net increase (decrease) in
   cash and cash equivalents..             --            --          5,339        (11,352)            --           (6,013)
Cash and cash equivalents at:
   Beginning of period .......             --            --          4,343         11,990             --           16,333
                                   -----------   -----------    -----------    ---=-------   -----------     ------------
   End of period .............     $       --    $       --     $    9,682     $      638    $        --     $     10,320
                                   ===========   ===========    ===-=======    ===========   ===========     ============


</TABLE>




                                       13
<PAGE>



<TABLE>
<CAPTION>

                      Consolidating Condensed Balance Sheet
                                 August 31, 1998

                                          Safety-Kleen                   Subsidiary
                            Safety-Kleen    Services,     Subsidiary        Non-       Elimination     Consolidated
($ in thousands)               Corp.          Inc.        Guarantors     Guarantors      Entries          Totals
                               -----          ----        ----------     ----------      -------          ------
ASSETS
<S>                          <C>           <C>           <C>            <C>            <C>             <C>

Current assets ...........   $        --   $        --   $    439,751   $   111,060    $        --     $    550,811
Property, plant and
   equipment, net ........            --            --      2,454,211       396,331            (40)       2,850,502
Investment in subsidiaries     1,496,759     2,776,635      1,322,059           166     (5,595,619)              --
Goodwill .................            --            --        951,655        71,499             --        1,023,154
Other non-current assets..            --            --         52,134           771             --           52,905
                             -----------   -----------    -----------   -----------    -----------     ------------
   Total assets ..........   $ 1,496,759   $ 2,776,635   $ 5,219,810    $   579,827    $(5,595,659)    $  4,477,372
                             ===========   ===========    ===========   ============   ===========     ============

LIABILITIES

Current liabilities ......   $     6,853   $    88,089    $   246,359   $    83,617 $           (2)    $    424,916
Non-current liabilities ..         --               --        722,622       111,964             --          834,586
Long-term debt ...........       125,200     1,661,989         16,334        49,641             --        1,853,164
Subordinated convertible
   debenture .............       350,000            --             --            --             --          350,000
                             -----------   -----------    -----------   -----------    -----------     ------------
   Total liabilities .....       482,053     1,750,078        985,315       245,222             (2)       3,462,666

STOCKHOLDERS'  EQUITY ....     1,014,706     1,026,557      4,234,495       334,605     (5,595,657)       1,014,706
                             -----------   -----------    -----------   -----------    -----------     ------------
Total liabilities and

   stockholders' equity ..   $ 1,496,759   $ 2,776,635    $ 5,219,810   $   579,827    $(5,595,659)    $  4,477,372
                             ===========   ===========    ===========   ===========    ===========     ============
</TABLE>


                                       14
<PAGE>

<TABLE>
<CAPTION>

                   Consolidating Condensed Statement of Income
                         Three Months Ended May 31, 1998
                                   (Unaudited)

                                               Safety-Kleen                    Subsidiary
                                Safety-Kleen     Services,      Subsidiary        Non-       Elimination    Consolidated
($ in thousands)                   Corp.           Inc.         Guarantors     Guarantors      Entries         Totals
                                   -----           ----         ----------     ----------      -------         ------
<S>                              <C>           <C>              <C>            <C>           <C>            <C>

Total revenues ...............   $       --    $         --     $  291,176     $   78,694    $    (4,165)   $     365,705
Operating expenses ...........           --              --        311,390         68,784         (4,165)         376,009
                                 ----------    ------------     ----------     ----------    ------------   -------------
Operating income (loss) ......           --              --        (20,214)         9,910             --          (10,304)
Interest expense, net ........        6,505          21,123            192          1,984             --           29,804
Undistributed earnings
   (losses) of subsidiaries ..      (31,751)         (9,464)            --             --         41,215               --
                                 -----------   -------------    -----------    ----------    -----------    -------------
Income (loss) before income
   tax expense (benefit) .....      (38,256)        (30,587)       (20,406)         7,926         41,215          (40,108)
Income tax expense (benefit)..       (2,937)         (8,912)        (5,644)         1,656             --          (15,837)
                                 -----------   -------------    -----------    ----------    -----------    -------------
Income (loss) before

   minority interest .........      (35,319)        (21,675)       (14,762)         6,270         41,215          (24,271)
Minority interest ............           --             --            (384)           619             --              235
                                 -----------   -------------    -----------    ----------    -----------    -------------
Income (loss) before

   extraordinary item ........      (35,319)        (21,675)       (15,146)         6,889         41,215          (24,036)
Extraordinary item, net of tax           --         (10,076)            --         (1,207)            --          (11,283)
                                 -----------   -------------    -----------    -----------   -----------    -------------
Net income (loss) ............   $  (35,319)   $    (31,751)    $  (15,146)    $    5,682    $    41,215    $     (35,319)
                                 ===========   =============    ===========    ===========   =======--==    =============


</TABLE>


<TABLE>
<CAPTION>

                   Consolidating Condensed Statement of Income
                         Nine Months Ended May 31, 1998
                                   (Unaudited)

                                                Safety-Kleen                   Subsidiary
                                  Safety-Kleen    Services,     Subsidiary        Non-       Elimination     Consolidated
($ in thousands)                        Corp.       Inc.        Guarantors     Guarantors      Entries         Totals
                                        -----       ----        ----------     ----------      -------         ------
<S>                                <C>           <C>            <C>            <C>           <C>                <C>

Total revenues ...............     $       --    $        --    $  596,378     $  158,259    $    (4,165)     $  750,472
Operating expenses ...........             --             --       581,315        132,019         (4,165)        709,169
                                   ----------    -----------    ----------     ----------    ------------     ----------
Operating income .............             --             --        15,063         26,240             --          41,303
Interest expense, net ........         19,265         33,684           419          4,682             --          58,050
Undistributed earnings
   (losses) of subsidiaries ..        (10,233)        19,750            --             --         (9,517)             --
                                   -----------    ----------    ----------     ----------    ------------     ----------
Income (loss) before income
   tax expense (benefit) .....        (29,498)       (13,934)       14,644         21,558         (9,517)        (16,747)
Income tax expense (benefit)..         (7,879)       (13,777)        9,143          6,231             --          (6,282)
                                   -----------    -----------   ----------     ----------    ------------     ----------
Income (loss) before

   minority interest .........        (21,619)          (157)        5,501         15,327         (9,517)        (10,465)
Minority interest ............             --             --            --            129             --             129
                                   ----------    ------------   ----------     ----------    ------------     ----------
Income (loss) before

   extraordinary item ........        (21,619)          (157)        5,501         15,456         (9,517)        (10,336)
Extraordinary item, net of tax             --        (10,076)           --         (1,207)            --         (11,283)
                                   -----------    -----------   ----------     -----------    -----------     ----------
Net income (loss) ............    $   (21,619)   $   (10,233)   $    5,501     $   14,249    $    (9,517)     $  (21,619)
                                   ===========   ============   ==========     ==========    ===========      ==========


</TABLE>




                                       15
<PAGE>


<TABLE>
<CAPTION>

                 Consolidating Condensed Statement of Cash Flows
                         Nine Months Ended May 31, 1998
                                   (Unaudited)

                                                    Safety-Kleen                  Subsidiary
                                    Safety-Kleen     Services,     Subsidiary        Non-       Elimination   Consolidated
($ in thousands)                       Corp.           Inc.        Guarantors     Guarantors      Entries       Totals
                                       -----           ----        ----------     ----------      -------       ------
<S>                                  <C>             <C>           <C>            <C>           <C>            <C>

Net cash provided by (used in)
   operating activities .......      $  (14,997)     $  (31,134)  $    41,451     $    59,614    $      --     $    54,934
                                     -----------     -----------   ----------     -----------    ---------     -----------
Cash flows from investing
   activities:
Cash expended on
   acquisition of business ....              --              --    (1,274,177)         (8,567)          --      (1,282,744)
Proceeds from sale of business               --              --        33,675              --           --          33,675
Purchases of property, plant
   and equipment ..............              --              --       (27,220)         (7,344)          --         (34,564)
Change in other, net ..........              --              --         7,683            (144)          --           7,539
                                     ----------      ----------    ----------     ------------   ---------     -----------
Net cash used in investing
   activities .................              --              --    (1,260,039)        (16,055)          --      (1,276,094)
                                     ----------      ----------    -----------    ------------   ---------     -----------
Cash flows from financing
   activities:
Issuance of common stock
   on exercise of stock options             436              --            --              --           --             436
Bank financing fees ...........              --         (36,946)           --              --           --         (36,946)
Borrowings of long-term debt ..              --       1,788,000            --          69,756           --       1,857,756
Repayment of long-term debt ...              --        (315,000)     (217,770)        (58,777)          --        (591,547)
Intercompany payable
   (receivable) ...............          14,561      (1,404,920)    1,417,135         (26,776)          --             --
                                     ----------      -----------   ----------     ------------   ---------     -----------
Net cash provided by (used in)
   financing activities .......          14,997          31,134     1,199,365         (15,797)          --       1,229,699
                                     ----------      ----------    ----------     ------------   ---------     -----------
Effect of exchange rate
   changes on cash ............              --              --            --            (202)          --            (202)
                                     ----------      ----------    ----------     ------------   ---------     -----------
Net increase (decrease) in
   cash and cash equivalents ..              --              --       (19,223)         27,560           --           8,337
Cash and cash equivalents at:
   Beginning of period ........              --              --        24,770         (13,610)          --          11,160
                                     ----------      ----------    ----------     ------------   ---------     -----------
   End of period ..............      $       --      $       --  $      5,547     $    13,950    $      --     $    19,497
                                     ==========      ==========    ==========     ============   =========     ===========

</TABLE>



                                       16
<PAGE>


MANAGEMENT'S  DISCUSSION  AND  ANALYSIS OF  FINANCIAL  CONDITION  AND RESULTS OF
OPERATIONS

         The following  discussion  and analysis  should be read in  conjunction
with the Company's  consolidated  financial statements and related notes thereto
included elsewhere herein.

         Results  associated with the April 1, 1998  acquisition of Safety-Kleen
Corp. ("Old Safety-Kleen") by Laidlaw Environmental  Services, Inc. ("Old LESI")
have been included in the Company's  consolidated  results as of the date of the
acquisition.

         The following  discussion  and analysis  includes  statements  that are
considered  forward-looking  based on the Company's  expectations  and, as such,
these  statements  are subject to  uncertainty  and risk.  See "Factors That May
Affect Future Results" below.


RESULTS OF OPERATIONS:
Three Months Ended May 31, 1999 compared with Three Months Ended May 31, 1998

Operating  results,  before  restructuring  and other charges and  extraordinary
items, are as follows ($ in millions):

<TABLE>
<CAPTION>

                                                             Three Months Ended May 31,
                                                             --------------------------
                                                             1999                 1998
                                                     ----------------------------------------
<S>                                                    <C>     <C>          <C>      <C>

Revenues                                               $400.9  100.0%       $365.7   100.0%
Operating expense                                       244.4   60.9%        244.0    66.7%
Depreciation and amortization                            33.3    8.3%         31.1     8.5%
Selling, general and administrative                      33.1    8.3%         35.1     9.6%
                                                      -------  ------       ------   ------
Operating income before restructuring and other
charges and extraordinary items                        $ 90.1   22.5%       $ 55.5    15.2%
                                                       ======  ======       ======   ======
</TABLE>


<TABLE>
<CAPTION>

Revenues

Components of revenue ($ in millions):                       Three Months Ended May 31,
                                                             --------------------------
                                                             1999                 1998
                                                     ---------------------------------------
<S>                                                    <C>     <C>          <C>      <C>
Collection and Recovery Services
    Industrial Services                                $198.1     50%       $168.3     46%
    Commercial and Institutional Services               133.6     33%         95.0     26%
                                                       ------    ---        ------     ---
Total Collection and Recovery Services                  331.7     83%        263.3     72%

Treatment and Disposal Services                          69.2     17%         82.4     22%

European Operations                                       0.0      0%         20.0      6%
                                                       ------    ---        ------     ---

     Total revenue                                     $400.9    100%       $365.7    100%
                                                       ======    ===        ======    ===

</TABLE>

                                       17
<PAGE>


         Revenues  increased  $35.2  million,  or 9.6%,  during the three months
ended May 31, 1999 compared to the three months ended May 31, 1998. Revenue from
collection  and  recovery  services  to  industrial  customers  increased  $29.8
million,  or 17.7%,  while  collection  and recovery  services to commercial and
institutional  customers  increased $38.6 million,  or 40.6%.  Increased revenue
from collection and recovery services reflects the inclusion of the acquired Old
Safety-Kleen  business for the full three months of the current period.  Revenue
from treatment and disposal services decreased $13.2 million, or 16.0%.

         The   Company   eliminates   inter-company   revenues   in   presenting
consolidated  financial results.  The majority of such eliminations occur at the
Company's  disposal  facilities  which  receive waste streams from the Company's
collection and recovery services network.

         Management's estimate of the components of the changes in the Company's
consolidated revenue is as follows:
                                                  Percentage Increase (Decrease)
                                                    Three Months Ended May 31,
                                                          1999 over 1998
                                                          --------------
Expansion of customer base by acquisition                    19.0%
Other, primarily through volume and price changes            (2.4%)
Divestitures and closures                                    (6.2%)
Foreign exchange rate changes                                (0.8%)
                                                             ------
     Total                                                    9.6%
                                                             =====

         The comparative  increase in revenue for the three months ended May 31,
1999 was primarily  due to the inclusion of a full three months  results for the
acquired  operations of Old  Safety-Kleen.  Revenues  from  existing  operations
decreased  primarily due to a $20 million  reduction in the level of activity in
the Company's harbor dredging and treatment  operations within the treatment and
disposal  component.  Absent  this $20 million  reduction,  the price and volume
component of the change in revenue  would have been a positive  3.4%.  Increased
throughput at the Company's landfill  operations  somewhat mitigated the overall
reduction.  Prior year revenues included  contributions from a thermal treatment
facility  which was closed on August 31, 1998,  and from the Company's  European
operations   which  were   partially   divested  on  December  23,   1998,   and
deconsolidated  as of November  30, 1998. A reduction in revenues due to foreign
exchange rate changes  resulted from a relative  decline in the Canadian  dollar
translation rate.

         While previously expecting to achieve internal revenue growth of 10% by
the end of fiscal 1999,  the Company now expects to achieve  such growth  levels
during fiscal 2000.

Operating Expenses

         Operating  expenses  increased $0.4 million,  or 0.2%, during the three
months ended May 31, 1999,  compared to the three months ended May 31, 1998. The
increase was primarily  attributable to additional  business obtained as part of
the  acquisition  of Old  Safety-Kleen.  As a percentage  of revenue,  operating
expense  decreased to 60.9% from 66.7% in the prior year,  primarily  due to the
increased  utilization  of existing  facilities  and other  operational  assets,
acquisition related cost reduction measures,  primarily personnel related costs,
and an increase in higher margin business.


                                       18
<PAGE>

Depreciation and Amortization Expense

         Depreciation and amortization  expense increased $2.2 million, or 7.1%,
during the three  months  ended May 31,  1999,  compared to the prior year.  The
increase related to the acquired operations of Old Safety-Kleen. As a percentage
of revenue,  depreciation and amortization expense was 8.3%, compared to 8.5% in
the  prior  year.   The  decrease  as  a  percentage  of  revenue  is  primarily
attributable to a reduction in capital  expenditures from historic levels of the
combined  companies  and  the  closure  of  certain  facilities  as  part of the
acquisition integration.

Selling, General and Administrative Expenses

         Selling, general and administrative expenses decreased $2.0 million, or
5.7% during the three  months ended May 31,  1999,  versus the prior year.  As a
percentage of revenue, selling, general and administrative expenses decreased to
8.3% from 9.6% in the prior year due to cost reduction measures and economies of
scale gained through the acquisition of Old Safety-Kleen.

Interest Expense

         Interest expense  increased $10.7 million,  or 35.9%,  during the three
months  ended May 31,  1999,  over the prior year as a result of the  additional
long term debt incurred to finance the acquisition of Old Safety-Kleen.

Equity in Earnings of Associated Companies

         On December 23,  1998,  the Company sold a 56% interest in its European
operations.  This transaction  resulted in no gain or loss. The Company accounts
for its remaining interest in the European operations on an equity basis.

Income Tax Expense

         The  effective  tax rate of 42% on income  before  equity  earnings and
taxes ($49.65  million) has increased  over the prior year effective rate due to
the  sale  of  56%  of  the  Company's   European   operations   and  additional
non-deductible   goodwill   amortization  related  to  the  acquisition  of  Old
Safety-Kleen.  The European  operations  had an effective tax rate below that of
the overall Company average.

         The  Company  expects  that the  effective  tax rate  will be higher in
subsequent  quarters  due to the  continuing  impact of the sale of the European
operations.


RESULTS OF OPERATIONS:

Nine Months Ended May 31, 1999 compared with Nine Months Ended May 31, 1998


                                       19
<PAGE>

Operating  results,  before  restructuring  and other charges and  extraordinary
items, are as follows ($ in millions):

<TABLE>
<CAPTION>

                                                             Nine Months Ended May 31,
                                                             -------------------------
                                                             1999               1998
                                                    -----------------------------------------
<S>                                                  <C>         <C>        <C>       <C>

Revenues                                             $1,270.1    100.0%     $750.5    100.0%
Operating expense                                       811.3     63.9%      513.2     68.4%
Depreciation and amortization                           104.2      8.2%       55.9      7.4%
Selling, general and administrative                     100.4      7.9%       74.3      9.9%
                                                     --------    -----      ------    -----
Operating income before restructuring and other
charges and extraordinary items                      $  254.2     20.0%     $107.1     14.3%
                                                     ========    =====      ======    =====
</TABLE>


<TABLE>
<CAPTION>

Revenues

Components of revenue ($ in millions):                       Nine Months Ended May 31,
                                                             -------------------------
                                                             1999               1998
                                                    -----------------------------------
<S>                                                    <C>       <C>        <C>       <C>
Collection and Recovery Services
    Industrial Services                              $  597.9     47%       $384.1     51%
    Commercial and Institutional Services               400.5     32%         95.0     13%
                                                       ------    ----       ------    ----
Total Collection and Recovery Services                  998.4     79%        479.1     64%

Treatment and Disposal Services                         240.0     19%        251.4     33%

European Operations                                      31.7      2%         20.0      3%
                                                       ------    ----       ------    ----

     Total revenue                                   $1,270.1    100%       $750.5    100%
                                                     ========    ====       ======    ====
</TABLE>


         Revenues  increased  $519.6 million,  or 69.2%,  during the nine months
ended May 31, 1999 compared to the nine months ended May 31, 1998.  Revenue from
collection  and  recovery  services to  industrial  customers  increased  $213.8
million,  or 55.7%,  while  collection  and recovery  services to commercial and
institutional  customers  generated  an  additional  $305.5  million.  Increased
revenue from  collection  and recovery  services  reflects the  inclusion of the
acquired Old Safety-Kleen business for the full nine month period.  Revenue from
treatment and disposal services  decreased $11.4 million,  or 4.5%. The acquired
European  operations of  Safety-Kleen  provided an  additional  $11.7 million in
revenue.

         The   Company   eliminates   inter-company   revenues   in   presenting
consolidated  financial results.  The majority of such eliminations occur at the
Company's  disposal  facilities  which  receive waste streams from the Company's
collection and recovery services network.


                                       20
<PAGE>

         Management's estimate of the components of the changes in the Company's
consolidated revenue is as follows:

                                                  Percentage Increase (Decrease)
                                                    Nine Months Ended May 31,
                                                        1999 over 1998
Expansion of customer base by acquisition                   73.9%
Other, primarily through volume and price changes            0.8%
Divestitures and closures                                   (4.3%)
Foreign exchange rate changes                               (1.2%)
                                                            ------
     Total                                                  69.2%
                                                            =====


         The  comparative  increase in revenue for the nine months ended May 31,
1999 was  primarily  due to the  inclusion  of the  acquired  operations  of Old
Safety-Kleen for the full period.  Revenues from existing  operations  decreased
primarily  due to a reduction in activity at the Company's  harbor  dredging and
treatment  operations  within the treatment and disposal  component.  Prior year
revenues  included  contributions  from a thermal  treatment  facility which was
closed on August 31, 1998 and from the Company's European  operations which were
partially  divested on December 23, 1998, and  deconsolidated as of November 30,
1998.  Prior year revenues also included  contributions  from an industrial  and
solid waste  landfill  which was  divested on December  18, 1997. A reduction in
revenues due to foreign  exchange rate changes  resulted from a relative decline
in the Canadian dollar translation rate.

Operating Expenses

         Operating expenses increased $298.1 million,  or 58.1%, during the nine
months ended May 31, 1999,  compared to the nine months ended May 31, 1998.  The
increase was primarily  attributable to additional  business obtained as part of
the  acquisition  of Old  Safety-Kleen.  As a percentage  of revenue,  operating
expense  decreased to 63.9% from 68.4% in the prior year,  primarily  due to the
increased  utilization  of existing  facilities  and  acquisition  related  cost
reduction measures.

Depreciation and Amortization Expense

         Depreciation  and  amortization  expense  increased  $48.3 million,  or
86.4%,  during the nine months ended May 31,  1999,  compared to the prior year.
The  increase  related to the  acquired  operations  of Old  Safety-Kleen.  As a
percentage or revenue,  depreciation and amortization expense was 8.2%, compared
to 7.4% in the prior year.  The increase as a percentage of revenue is primarily
attributable  to the  amortization  of the excess purchase price relating to the
acquisition of Old Safety-Kleen.

Selling, General and Administrative Expenses

         Selling,  general and administrative  expenses increased $26.1 million,
or 35.1% during the nine months ended May 31, 1999,  versus the prior year. As a
percentage of revenue, selling, general and administrative expenses decreased to
7.9% from 9.9% in the prior year due to cost reduction measures and economies of
scale gained through the acquisition of Old Safety-Kleen.

                                       21
<PAGE>


Interest Expense

         Interest expense  increased $69.1 million,  or 119.0%,  during the nine
months  ended May 31,  1999,  over the prior year as a result of the  additional
long term debt incurred to finance the acquisition of Old Safety-Kleen.

Equity in Earnings of Associated Companies

         On December 23,  1998,  the Company sold a 56% interest in its European
operations, realizing cash proceeds of $154.0 million. This transaction resulted
in no gain or loss. Effective December 1, 1998, the Company commenced accounting
for its remaining  interest in the European  operations on an equity basis.  The
equity  earnings  recorded in the quarter ended May 31, 1999,  represent 100% of
the  European  operations  for the month of  December,  1998,  and reflect a 44%
interest  thereafter.  Thus, the European operations' results have been excluded
from revenue and expenses effective December 1, 1998.

Income Tax Expense

         The  effective  tax rate on income  before  equity  earnings and income
taxes increased to 43% from 38% due to the sale of 56% of the Company's European
operations and additional  non-deductible  goodwill  amortization related to the
acquisition of Old Safety-Kleen.


FACTORS THAT MAY AFFECT FUTURE RESULTS

         This report  contains  various  forward-looking  statements  within the
meaning of the  Private  Securities  Litigation  Reform  Act of 1995,  including
financial,  operating  and  other  projections.  These  statements  are based on
current   plans  and   expectations   of  the  Company  and  involve  risks  and
uncertainties   that  could  cause  actual  future  activities  and  results  of
operations   to  be   materially   different   from   those  set  forth  in  the
forward-looking statements.

         Important  factors that could cause actual  results to differ  include,
among others, risks associated with acquisitions and achieving the targeted cost
savings  levels,  fluctuations  in operating  results  because of  acquisitions,
changes in applicable  government  regulations  (environmental  and other),  the
impact of litigation,  competition, and risks associated with the operations and
growth of the newly  acquired  business of Old  Safety-Kleen  and other  factors
described in Part I, Item 1 of the Company's  report on Form 10-K for the Twelve
Months  Ended  August 31,  1998.  As a result of these  factors,  the  Company's
revenue and income could vary  significantly  from quarter to quarter,  and past
financial  performance  should not be considered a reliable  indicator of future
performance.


CAPITALIZATION

         On  November  24,  1998,   the   Company's   shareholders   approved  a
one-for-four  reverse stock split which became effective on December 1, 1998. As
a result,  shareholders received one share of Safety-Kleen common stock for each
four shares previously held.


                                       22
<PAGE>

         On November  15, 1998,  the Company  issued  635,208  shares to satisfy
interest due on the subordinated convertible debenture.

         On May 17, 1999, the Company issued 533,333 shares to satisfy  interest
due on the subordinated convertible debenture.

         On May 17, 1999, the Company issued $225 million 9.25% Senior Notes due
2009 (the "Senior Notes") in a private  offering.  Net proceeds from the sale of
the Senior  Notes,  after the  underwriting  discount and other  expenses,  were
approximately  $214  million.  The net proceeds will be used to finance the cash
portion of the purchase price for the repurchase of the subordinated convertible
debenture  (the  "Repurchase").  The net proceeds will be held in escrow pending
the attainment of shareholder  approval for the issuance of  approximately  11.3
million  common  shares of the  Company  to  finance  the stock  portion  of the
purchase price for the Repurchase.  The Company is required to redeem the Senior
Notes for 101% of the principal amount plus accrued and unpaid interest, if any,
if the Repurchase has not been completed by September 30, 1999.


LIQUIDITY

         Total cash provided by operations  during the nine months ended May 31,
1999 was $91.1  million.  This was composed of $224.4  million  from  operations
before financing working capital requirements of $65.9 million and $67.4 million
related to spending on acquisition liabilities.

         On December 23, 1998, the Company announced the recapitalization of its
European  operations  resulting  in the  sale  of 56%  of the  Company's  equity
interest in that entity.  As a result of the  recapitalization  the Company will
receive gross proceeds of $154.0  million.  During the nine months ended May 31,
1999,  the Company  received  $138.6  million of net proceeds (net of $5 million
cash left in the European  operations  at the time of sale).  The balance of the
gross  proceeds  will be  received as a dividend  tax refund  within the current
year.

         The  Company's  primary  sources  of  liquidity  are  cash  flows  from
operations,  existing cash and short-term  investments of $10.3 million, and the
short-term  unused  working  capital  bank lines and unused cash  portion of the
Senior Credit Facility's revolver tranche of $299.9 million.

         The Company  expects to fund capital  expenditures,  debt repayment and
environmental liability requirements from cash flows from operations.


                                       23
<PAGE>


CAPITAL EXPENDITURES AND CAPITAL RESOURCES

         Investing  activities for the nine months ended May 31, 1999, used cash
of $139.9 million.  Net expenditures for the purchase of fixed assets for normal
replacement  requirements  and  increases in services  were $48.9  million,  net
proceeds from the sale of the European  operations  were $138.6  million and the
purchase of short term investments from the proceeds of the Senior Note issue on
May 17, 1999 were $219.4 million.  The Company's projected capital  expenditures
for fiscal 1999 are approximately $65 to $70 million.  The Company believes that
it has adequate resources to finance these expenditures.

         The Company's Senior Credit Facility contains negative, affirmative and
financial  covenants  customarily  found in  credit  agreements  for  financings
similar to the financing  provided under the Senior Credit  Facility,  including
covenants limiting annual capital  expenditures,  restricting debt,  guaranties,
liens, mergers and consolidations, sales of assets and payment of dividends. The
Company was in compliance with all of its covenants at May 31, 1999.

         The  Company's  Senior  Notes  are  effectively   subordinated  to  the
Company's  subsidiaries'  indebtedness.  The payment of  dividends,  advances or
other  distributions from the Company's  subsidiaries to the Company,  as may be
required to service the Senior  Notes,  may be restricted as they are subject to
the various indentures, covenants and other obligations of the subsidiaries.


YEAR 2000 READINESS DISCLOSURE

         The Year 2000 ("Y2K") issue is the result of computer  programs using a
two-digit format, as opposed to four digits, to indicate the year. Such computer
programs  will be unable to interpret  dates  beyond the year 1999,  which could
cause a system  failure or other  computer  errors,  leading to  disruptions  in
operations.  The  Company  developed  a  three-phase  program  for  Y2K  systems
compliance.  Phase I identified  those systems with respect to which the Company
had exposure to Y2K issues.  Phase II was the development and  implementation of
action  plans  for  Y2K  compliance.  Phase  III was the  final  testing  of the
appropriate major areas of exposure to ensure compliance.

         Phase I was completed  early in fiscal 1998 and identified  three major
areas of Y2K non-compliance:

         (1)      certain modules of our financial and operational systems,

         (2)      incinerator distributed control systems, and

         (3)      third-party vendor relationships.


                                       24
<PAGE>

         The  Phase II action  plans  have been  developed  with  implementation
completed  during  the  second  calendar  quarter  of  1999.  Our  plan to bring
deficient  financial  systems into compliance  through the previously  scheduled
purchase of software  upgrades has been  accomplished,  and these  upgrades have
tested   satisfactorily.   Remediation  of  the  operational  systems  has  been
accomplished through a combination of hardware and software upgrades and program
changes.  The deficiencies in the incinerator  distributed  control systems have
been  remedied  by the  installation  of  upgrades  purchased  from the  systems
vendors.  With respect to the third-party vendors, we have contacted most of our
major suppliers and have received  indications that they are either compliant or
intend to be compliant by mid-calendar year 1999.

         In  fiscal  1999 to date,  the  Company  incurred  approximately  $7.25
million of costs in connection with its Y2K compliance efforts ($1.4 million was
incurred in fiscal 1998).  $5.0 million related to software upgrades and program
changes to certain modules of the Company's  financial and operational  systems,
$1.0  million  related to upgrades  to network  operations  equipment  and $1.25
million  related to software  upgrades to the  incinerator  distributed  control
systems.

         Phase III testing,  to ensure  compliance  once the Phase II plans were
implemented,  was  successfully  completed during the second calendar quarter of
1999. As all three phases have now been completed, the Company is in the process
of developing worst case contingency plans. To the extent we experience material
Y2K problems and do not have any  contingency  plan in effect for remedying such
problems,  such Y2K problems could have a material adverse effect on our results
of operations, financial conditions and cash flow.

         While we believe  the  occurrence  of such a scenario  is  unlikely,  a
possible  worst case scenario  might include (a) delays,  inaccuracies  or other
difficulties  with respect to billing customers or the loss of customer records,
(b)  our  inability  to  run  one  or  more  of our  incinerators  or  recycling
facilities,  and (c) our key vendors not being able to supply goods and services
on a timely basis.  The  financial  impact of any or all of the above worst case
scenarios has not been and cannot be estimated by management due to the numerous
uncertainties and variables associated with such scenarios.


                           PART II - OTHER INFORMATION

ITEM 1.  LEGAL PROCEEDINGS.

GENERAL

         The business of the Company's  hazardous and industrial  waste services
is continuously  regulated by federal,  state,  provincial and local  provisions
that have been enacted or adopted,  regulating  the discharge of materials  into
the environment or primarily for the purpose of protecting the environment.  The
nature of the Company's businesses results in its frequently becoming a party to
judicial or  administrative  proceedings  involving  all levels of  governmental
authorities and other interested parties. The issues that are involved generally
relate to  applications  for  permits  and  licenses  by the  Company  and their
conformity with legal



                                       25
<PAGE>

requirements and alleged technical  violations of existing permits and licenses.
The Company does not believe that these issues will be material to the Company's
operations or financial condition.  At May 31, 1999, subsidiaries of the Company
were  involved in five  proceedings  of the latter type  relating  primarily  to
activities at waste treatment, storage and disposal facilities where the Company
believes  sanctions  involved in each instance may exceed $100,000.  The Company
believes  that  the  ultimate  disposition  of  these  issues  will  not  have a
materially adverse effect upon the Company's  consolidated financial position or
results of operations.

         The Company  frequently  becomes a party to legal  proceedings  wherein
persons claim injury resulting from the use of Company's parts cleaner equipment
and/or  cleaning  products.  A number of legal  proceedings  of this  nature are
currently pending in various courts and jurisdictions  throughout North America.
The Company  believes that the ultimate  disposition of these legal  proceedings
will not have a  materially  adverse  effect  upon  the  Company's  consolidated
financial position or results of operations.

         In the United States, CERCLA imposes financial liability on persons who
are  responsible for the release of hazardous  substances into the  environment.
Present  and  past  owners  and  operators  of  sites  which  release  hazardous
substances,  as well as generators and  transporters of the waste material,  are
jointly and severally liable for remediation costs and environmental  damage. At
May  31,  1999,  the  Company  had  been  notified  that  it  was a  potentially
responsible  party  in  connection  with 51  locations  in its  hazardous  waste
management and other businesses. The Company continually reviews its status with
respect to each  location  and the  extent of its  alleged  contribution  to the
volume of waste at the location,  the available evidence  connecting the Company
to that location,  and the numbers and financial  soundness of other potentially
responsible parties at the location. Based upon presently available information,
the  Company  does not  believe  that  potential  liabilities  arising  from its
involvement with these locations will be material to the Company's operations or
financial condition.

TAX MATTERS

         On March 1, 1999, Laidlaw Inc. ("Laidlaw")  announced a settlement of a
dispute between  Laidlaw's  United States  subsidiaries  and the Commissioner of
Internal  Revenue relating to the timing and  deductibility  for tax purposes of
interest attributable to loans owing to related foreign persons during the years
from 1986 to 1994.

         The total net after tax cash cost to Laidlaw will be approximately $226
million. The payment includes  approximately $121 million in taxes together with
interest of approximately $161 million ($105 million after tax).

         This  settlement  resolves  matters  in the  United  States  Tax  Court
(captioned  as  Laidlaw   Transportation,   Inc.  and  Subsidiaries  et.  al  v.
Commissioner of Internal  Revenue,  Docket Nos. 9361-94 and 9362-94) relating to
the 1986 to 1991  fiscal  years as well as claims  raised in a thirty day letter
relating to the 1992 to 1994 fiscal years.  The Commissioner of Internal Revenue
has asserted claims totaling approximately $500 million.

         Pursuant to the  agreement  dated  February 6, 1997 among the  Company,
Laidlaw  and  Laidlaw  Transportation,   Inc.  ("LTI"),   Laidlaw  and  LTI  are
responsible  for any tax  liabilities

                                       26
<PAGE>

resulting from these matters. Based upon discussions with Laidlaw, the Company's
income tax  provision  determined  on a separate  return basis during the period
audited by the internal  Revenue Service was sufficient and no additional  taxes
or interest are due to or from Laidlaw as a result of the settlement.

VILLE MERCIER FACILITY

         On or about  February 9 and March 12,  1999,  Ville  Mercier  and three
neighboring   municipalities   filed  separate  legal  proceedings  against  the
subsidiary and certain related  companies  together with certain former officers
and directors,  as well as against the Government of Quebec. The lawsuits assert
that the defendants are jointly and severally  responsible for the contamination
of groundwater in the region, which Plaintiffs claim was caused by contamination
from the  former  Ville  Mercier  lagoons,  and which  they  claim  caused  each
municipality  to incur  additional  costs to  supply  drinking  water  for their
citizens  since the 1970's and early  1980's.  The four  municipalities  claim a
total of  CDN$1,595,000 as damages for additional costs to obtain drinking water
supplies and seek an  injunctive  order to obligate the  defendants to remediate
the  groundwater  in the  region.  For the reasons  stated in the related  legal
proceedings described in PART II, Item 3 of the Registrant's Report on Form 10-K
for the twelve  months ended August 31, 1998,  the  subsidiary  will continue to
assert that it has no responsibility  for the ground water  contamination in the
region.

       Other than as herein reported there have been no additional significant
legal proceedings nor any material changes in the legal proceedings  reported in
PART II, Item 3 of the  Registrant's  Report on Form 10-K for the twelve  months
ended August 31, 1998.


PART II - OTHER INFORMATION


ITEM 2.  CHANGES IN SECURITIES AND USE OF PROCEEDS.

(a) In May 1999 the Company  issued $225 million  9.25% Senior Notes due May 15,
2009,  the proceeds of which are intended to be used to finance the cash portion
of the purchase price for the  repurchase of the  $350,000,000  5%  Subordinated
Convertible  Pay-In-Kind  debenture  (the "PIK  Debenture")  issued  to  Laidlaw
Transportation, Inc. on May 15, 1997, for expenses relating to the repurchase of
the PIK Debenture and for general corporate purposes. For information concerning
this financing  arrangement see Note 3 to the Consolidated  Financial Statements
included  in Item 1 of Part I of this  report  which is hereby  incorporated  by
reference.

(b) On May 17, 1999, the  Registrant  issued 533,333 shares of its common stock,
par value $1.00 per share ("SK Stock"),  to Laidlaw Finance  (Barbados) Ltd., as
interest payment on the PIK Debenture.  The Company believes that the shares are
exempt from  registration  pursuant to Section  (4)(2) of the  Securities Act of
1933,  as amended  (the "Act").  In  determining  to issue the SK Stock  without
registration under the Act management  considered the fact that the offering was
being made to a single offeree in connection with the interest payment under the
Debenture  and further,  Laidlaw  Finance  (Barbados)  Ltd.  represented  to the
Registrant that it was acquiring the SK Stock for investment and not with a view
to, or for resale in connection with, any distribution of the SK Stock.


                                       27
<PAGE>


ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K.

(3)(a) Restated  Certificate of  Incorporation of the Company dated May 13, 1997
and  Amendment  to  Certificate  of  Incorporation  dated May 15,  1997 filed as
Exhibit 3(a) to the  Registrant's  Form 10-Q for the Quarter  ended May 31, 1997
and incorporated herein by reference.

(3)(a)(i)  Certificate  of  Correction  Filed to Correct a Certain  Error in the
Restated and Amended  Certificate of  Incorporation of the Company dated October
15, 1997 filed as Exhibit  (3)(a)(i) to the Registrant's  Form 10-K for the Year
ended August 31, 1997, and incorporated herein by reference.

(3)(a)(ii) Certificate of Amendment to the Restated Certificate of Incorporation
of the  Company  dated  November  25, 1998 filed as Exhibit  (3)(a)(iii)  to the
Registrant's  Form 10-Q for the quarter ended November 30, 1998 and incorporated
herein by reference.

(3)(a)(iii)   Certificate   of  Amendment  to  the   Restated   Certificate   of
Incorporation of the Company dated November 30, 1998 filed as Exhibit (3)(a)(iv)
to the  Registrant's  Form 10-Q for the  quarter  ended  November  30,  1998 and
incorporated herein by reference.

(3)(b) Amended and Restated  Bylaws of the Company filed as Exhibit 4(ii) to the
Registrant's  Current  Report on Form 8-K dated July 29,  1997 and  incorporated
herein by reference.

(4)(a) Indenture dated as of May 29, 1998 between LES, Inc. (a subsidiary of the
Registrant), Registrant, subsidiary guarantors of the Registrant and The Bank of
Nova Scotia Trust  Company of New York,  as trustee filed as Exhibit 4(b) to the
Registrant's  Form S-4 Registration  Statement No. 333-57587 filed June 24, 1998
and incorporated herein by reference.

(4)(b)  First  Supplemental  Indenture  effective  as of November 15, 1998 among
Safety-Kleen Services, Inc. the Registrant, SK Europe, Inc. and The Bank of Nova
Scotia  Trust  Company of New York,  as trustee  filed as Exhibit  (4)(e) to the
Registrant's  Form S-4  Registration  Statement  No.  filed  July  12,  1999 and
incorporated herein by reference.

(4)(c)  Indenture  dated as of May 17, 1999 between  Registrant  and the Bank of
Nova Scotia Trust Company of New York, as trustee filed as Exhibit (4)(b) to the
Registrant's  Form S-4  Registration  Statement  No.  filed  July  12,  1999 and
incorporated herein by reference.

(4)(d) Registration Rights Agreement dated as of May 17, 1999 between Registrant
and TD  Securities,  NationsBanc  Montgomery  Securities LLC and Raymond James &
Associates,   Inc.  filed  as  Exhibit  (4)(a)  to  the  Registrant's  Form  S-4
Registration  Statement  No.  filed  July 12,  1999 and  incorporated  herein by
reference.

(4)(e) Amended and Restated  Credit  Agreement among Laidlaw  Chem-Waste,  Inc.,
Laidlaw Environmental Services (Canada) Ltd., Toronto Dominion (Texas) Inc., The
Toronto-Dominion  Bank,  TD  Securities  (USA)  Inc.,  The Bank of Nova  Scotia,
NationsBank,  N.A. and The First National Bank of Chicago and NationsBank,  N.A.
as  Syndication  Agent dated as of April 3, 1998,  filed as Exhibit  4(f) to the
Registrant's Form 10-Q for the quarter ended February 28, 1999, and incorporated
herein by reference.

                                       28
<PAGE>

(4)(f)  Supplement to the Amended and Restated  Credit  Agreement  among Laidlaw
Chem-Waste, Inc., Laidlaw Environmental Services (Canada) Ltd., Toronto Dominion
(Texas) Inc., The  Toronto-Dominion  Bank, TD Securities (USA) Inc., The Bank of
Nova  Scotia,  NationsBank,  N.A.  and The First  National  Bank of Chicago  and
NationsBank,  N.A.  as  Syndication  Agent  dated as of April 3, 1998,  filed as
Exhibit 4(e) to a subsidiary of the Registrant's Form S-4 Registration Statement
No. 333-57587 filed June 24, 1998 and incorporated herein by reference.

(4)(g) Waiver and First Amendment to the Amended and Restated  Credit  Agreement
dated  as of May 15,  1998  among  LES,  Inc.,  Laidlaw  Environmental  Services
(Canada) Ltd., the Lenders, Toronto Dominion (Texas), Inc., The Toronto Dominion
Bank, TD Securities (USA) Inc., The Bank of Nova Scotia, NationsBank,  N.A., The
First  National  Bank of Chicago and  Wachovia  Bank filed as Exhibit  4(f) to a
subsidiary of the  Registrant's  Form S-4  Registration  Statement No. 333-57587
filed June 24, 1998 and incorporated herein by reference.

(4)(h)  Commitment  to Increase  Supplement  to the Amended and Restated  Credit
Agreement  dated as of June 3,  1998  among  LES,  Inc.,  Laidlaw  Environmental
Services (Canada) Ltd., the Lenders, Toronto Dominion (Texas), Inc., The Toronto
Dominion Bank, TD Securities  (USA) Inc., The

Bank of Nova Scotia,  NationsBank,  N.A., The First National Bank of Chicago and
Wachovia Bank filed as Exhibit 4(g) to a subsidiary of the Registrant's Form S-4
Registration Statement No. 333-57587 filed June 24, 1998 and incorporated herein
by reference.

(4)(i) Second Amendment to the Amended and Restated Credit Agreement dated as of
November 20, 1998 among  Safety-Kleen  Services,  Inc.  (formerly  known as LES,
Inc.),   Safety-Kleen   Services  (Canada)  Ltd.   (formerly  known  as  Laidlaw
Environmental  Services  (Canada) Ltd.), the Lenders,  Toronto Dominion (Texas),
Inc.,  The Toronto  Dominion  Bank, TD Securities  (USA) Inc.,  The Bank of Nova
Scotia, NationsBank,  N.A., The First National Bank of Chicago and Wachovia Bank
N.A., filed as Exhibit (4)(j) to the Registrants Form 10-Q for the quarter ended
February 28, 1999 and incorporated herein by reference.

(4)(j) Waiver and Third Amendment to the Amended and Restated  Credit  Agreement
dated as of May 6, 1999 among  Safety-Kleen  Services,  Inc.  (formerly known as
LES,  Inc.),  Safety-Kleen  Services  (Canada) Ltd.  (formerly  known as Laidlaw
Environmental  Services  (Canada) Ltd.), the Lenders,  Toronto Dominion (Texas),
Inc.,  The Toronto  Dominion  Bank, TD Securities  (USA) Inc.,  The Bank of Nova
Scotia, NationsBank,  N.A., The First National Bank of Chicago and Wachovia Bank
N.A. filed as Exhibit (4)(k) to the Registrant's Form S-4 Registration Statement
No. filed July 12, 1999 and incorporated herein by reference.

(4)(k) $350,000,000 5% Subordinated  Convertible  Pay-In-Kind Debenture due 2009
issued by Registrant on May 15, 1997 to Laidlaw Transportation, Inc. the form of
which was included as an appendix to the Registrant's Definitive Proxy Statement
on Form DEF 14A, filed on May 1, 1997 and incorporated herein by reference.

(4)(l)  Registration  Rights  Agreement  dated May 15, 1997 between  Registrant,
Laidlaw Transportation,  Inc. and Laidlaw Inc. the form of which was included as
an appendix to the  Registrant's  Definitive  Proxy  Statement  on Form DEF 14A,
filed on May 1, 1997 and incorporated herein by reference.

                                       29
<PAGE>

(4)(m)  Indenture  dated as of May 1, 1993  between the  Industrial  Development
Board  of  the   Metropolitan   Government  of  Nashville  and  Davidson  County
(Tennessee)  and  NationsBank of Tennessee,  N.A.,  filed as Exhibit 4(f) to the
Registrant's  Form 10-Q for the Quarter  ended May 31,  1997,  and  incorporated
herein by reference.

(4)(n)  Indenture of Trust dated as of August 1995 between Tooele  County,  Utah
and West One Bank,  Utah, now known as U.S.  Bank, as Trustee,  filed as Exhibit
4(h) to the  Registrant's  form 10-Q for the  Quarter  ended May 31,  1997,  and
incorporated herein by reference.

(4)(o)  Indenture of Trust dated as of July 1, 1997 between Carbon County,  Utah
and U.S. Bank, a national banking association, as Trustee, filed as Exhibit 4(i)
to the  Registrant's  Form  10-Q  for  the  Quarter  ended  May  31,  1997,  and
incorporated herein by reference.

(4)(p)  Indenture of Trust dated as of July 1, 1997 between Tooele County,  Utah
and U.S. Bank, a national banking association, as Trustee, filed as Exhibit 4(j)
to the  Registrant's  Form  10-Q  for  the  Quarter  ended  May  31,  1997,  and
incorporated herein by reference.

(4)(q) Indenture of Trust dated as of July 1, 1997 between California  Pollution
Control Financing  Authority and U.S. Bank, a national banking  association,  as
Trustee,  filed as Exhibit  4(k) to the  Registrant's  Form 10-Q for the Quarter
ended May 31, 1997, and incorporated herein by reference.

(4)(r) Promissory Note dated May 15, 1997 for $60,000,000 from the Registrant to
Westinghouse  Electric  Corporation,  filed as Exhibit 4(n) to the  Registrant's
Form  10-Q for the  Quarter  ended  May 31,  1997,  and  incorporated  herein by
reference.

(4)(s) Letter dated May 7, 1999 from Toronto-Dominion  (Texas) Inc. (as assignee
of  Westinghouse  Electric  Corporation)  and  agreed to by the  Registrant  and
Laidlaw Inc.  amending the terms of the  Promissory  Note dated May 15, 1997 (as
referenced in Exhibit (4)(r)) filed as Exhibit (4)(t) to the  Registrant's  Form
S-4 Registration  Statement No.    filed July 12, 1999 and  incorporated  herein
 by reference.

(4)(t)  Guaranty  Agreement  dated May 15, 1997 by Laidlaw Inc. to  Westinghouse
Electric  Corporation  guaranteeing  Promissory  Note  dated  May 15,  1997  (as
referenced  in  Exhibit  (4)(r))  from   Registrant  to  Westinghouse   Electric
Corporation),  filed  as  Exhibit  4(o) to the  Registrant's  Form  10-Q for the
Quarter ended May 31, 1997, and incorporated herein by reference.

(4)(u) Escrow  Agreement dated as of May 17, 1999 between the Registrant and the
Bank of Nova Scotia  Trust  Company of New York,  as  trustee,  filed as Exhibit
(4)(c) to the Registrant's  Form S-4  Registration  Statement No.     filed July
12, 1999 and incorporated herein by reference.

(4)(v) Other instruments defining the rights of holders of nonregistered debt of
the  Registrant  have been  omitted from this exhibit list because the amount of
debt  authorized  under any such  instrument  does not  exceed  10% of the total
assets of the Registrant and its subsidiaries.  The Registrant agrees to furnish
a copy of any such instrument to the Commission upon request.

                                       30
<PAGE>


(10)(a)  Agreement  and Plan of Merger  dated as of March 16,  1998 by and among
Registrant, LES Acquisition, Inc., and Safety-Kleen Corp. included as Annex A of
Safety-Kleen's  Revised Amended  Prospectus on Form 14D-9 filed as Exhibit 62 to
Safety-Kleen's  Amendment  No.  28 to  Schedule  14-9A on March  17,  1998,  and
incorporated herein by reference.

(10)(b) Stock  Purchase  Agreement  between  Westinghouse  Electric  Corporation
(Seller) and Rollins Environmental Services, Inc. (Buyer) for National Electric,
Inc. dated March 7, 1995 filed as Exhibit 2 to the  Registrant's  Current Report
on Form 8-K filed on June 13, 1995 and incorporated herein by reference.

(10)(c) Second  Amendment to Stock Purchase  Agreement (as referenced in Exhibit
(10)(b)  above),  dated May 15, 1997 among  Westinghouse  Electric  Corporation,
Rollins Environmental  Services, Inc. and Laidlaw Inc., filed as Exhibit 4(m) to
the Registrant's  Form 10-Q for the Quarter ended May 31, 1997, and incorporated
herein by reference.

(10)(d) Rollins  Environmental  Services,  Inc. 1982 Incentive Stock Option Plan
filed with Amendment No. 1 to the Company's  Registration  Statement No. 2-84139
on Form S-1 dated June 24, 1983 and incorporated herein by reference.

(10)(e) Rollins Environmental  Services,  Inc. 1993 Stock Option Plan filed with
the  Company's  Proxy  Statement  for the Annual  Meeting of  Shareholders  held
January 28, 1994 and incorporated herein by reference.

(10)(f)  Registrant's  1997  Stock  Option  Plan,  filed as  Exhibit  4.4 to the
Company's  Registration  Statement No.  333-41859 on Form S-8 dated December 10,
1997 and incorporated herein by reference.

(10)(g)  Registrant's  Director's Stock Option Plan, filed as Exhibit 4.5 to the
Company's  Registration  Statement No.  333-41859 on Form S-8 dated December 10,
1997 and incorporated herein by reference.

(10)(h) Stock Purchase  Agreement  dated February 6, 1997 among the  Registrant,
Laidlaw Inc., and Laidlaw  Transportation,  Inc.  included as an appendix to the
Definitive Proxy Statement on Form DEF 14A filed on May 1, 1997 and incorporated
herein by reference.

(10)(i) Corporate  Incentive Plan for fiscal year 1999, filed as Exhibit (10)(i)
to the  Registrant's  Form 10-Q for the  quarter  ended  November  30,  1998 and
incorporated herein by reference.

(10)(j)  Operations  Management  Incentive  Plan for  fiscal  year 1999 filed as
Exhibit (10)(j) to the Registrant's Form 10-Q for the quarter ended November 30,
1998 and incorporated herein by reference.

(10)(k)  Registrant's  U.S.  Supplemental  Executive  Retirement  Plan  filed as
Exhibit 10(g) to the Registrant's  10-Q for the quarter ended November 30, 1997,
and incorporated herein by reference.

(10)(l) Form of Change of Control  Agreement  LES-A1,  filed as Exhibit 10(k) to
the

                                       31
<PAGE>

Registrant's  10-K for the year ended  August 31,  1998,  and  incorporated
herein by reference.

(10)(m) Form of Change of Control Agreement  LES-B-1,  filed as Exhibit 10(l) to
the  Registrant's  10-K for the year ended  August 31,  1998,  and  incorporated
herein by reference.

(10)(n) Form of Change of Control  Agreement  LES-C1,  filed as Exhibit 10(m) to
the  Registrant's  10-K for the year ended  August 31,  1998,  and  incorporated
herein by reference.

(10)(o)   Securities   Purchase  Agreement  dated  April  19,  1999,  among  the
Registrant,  Laidlaw Inc. and Laidlaw International Finance Corporation filed as
Exhibit (10)(o) to the Registrant's  Form S-4  Registration  Statement No.
filed July 12, 1999 and incorporated herein by reference.

(11)     Statement of Computation of Per Share Earnings

(12)     Statement Re: Computation of Ratios

(27)     Financial Data Schedule.

(b)      Reports on Form 8-K.

The Company  filed a Current  Report on Form 8-K,  dated April 20,  1999,  which
contained Item 5 related to a press release  announcing an agreement to purchase
the Company's outstanding $350 million 5% subordinated  convertible  pay-in-kind
debenture  from  Laidlaw  Inc.  for  cash and  common  stock  and the  Company's
intention  to offer up to $225  million  of  senior  notes due 2009 in a private
placement.

The  Company  filed a  Current  Report on Form 8-K,  dated  May 5,  1999,  which
contained Item 5 related to a press release  announcing the Company's  intention
to offer up to $225 million of senior notes due 2009 in a private placement.

The  Company  filed a  Current  Report on Form 8-K,  dated May 10,  1999,  which
contained  Item 5 related to a press  release  announcing  that the  Company had
received notice from the Securities and Exchange Commission (the "SEC") that the
SEC advised of its  intention to fully review the  Company's  Preliminary  Proxy
Statement filed on April 23, 1999, in connection  with the Company's  previously
announced repurchase of the outstanding $350 million 5% subordinated convertible
pay-in-kind debenture from Laidlaw Inc.

The  Company  filed a  Current  Report on Form 8-K,  dated May 17,  1999,  which
contained Item 5 related to a press release  announcing  that the Company was in
the process of completing  its offering of $225 million of senior notes due 2009
in a private placement.

The  Company  filed a  Current  Report on Form 8-K,  dated May 27,  1999,  which
contained  Item 7, unaudited pro forma combined  financial  information  for the
year ended August 31, 1998.


                                       32
<PAGE>





                                   SIGNATURES

       Pursuant to the requirements of the Securities  Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.



   DATE:  July 15, 1999                   SAFETY-KLEEN CORP.
                                          ------------------
                                               (Registrant)



                                         /s/Kenneth W. Winger
                                         -------------------------------------
                                         Kenneth W. Winger
                                         President and Chief Executive Officer



                                        /s/Paul R. Humphreys
                                        --------------------------------------
                                        Paul R. Humphreys
                                        Senior Vice President-Finance and
                                        Chief Financial Officer





                                       33
<PAGE>





                                INDEX TO EXHIBITS

(3)(a)            Restated Certificate of  Incorporation  of the  Company  dated
                  May 13, 1997 and  Amendment to  Certificate  of  Incorporation
                  dated May 15, 1997 filed  as Exhibit 3(a) to the  Registrant's
                  Form 10-Q for the Quarter ended May 31, 1997 and  incorporated
                  herein by reference.

(3)(a)(i)         Certificate of Correction  Filed to Correct a Certain Error in
                  the Restated and Amended  Certificate of  Incorporation of the
                  Company dated  October 15, 1997 filed as Exhibit  (3)(a)(i) to
                  the Registrant's Form 10-K for the Year ended August 31, 1997,
                  and incorporated herein by reference.

(3)(a)(ii)        Certificate  of  Amendment  to  the  Restated  Certificate  of
                  Incorporation  of the Company dated November 25, 1998 filed as
                  Exhibit  (3)(a)(iii)  to the  Registrant's  Form  10-Q for the
                  quarter  ended  November 30, 1998 and  incorporated  herein by
                  reference.

(3)(a)(iii)       Certificate  of  Amendment  to  the  Restated  Certificate  of
                  Incorporation  of the Company dated November 30, 1998 filed as
                  Exhibit  (3)(a)(iv)  to the  Registrant's  Form  10-Q  for the
                  quarter  ended  November 30, 1998 and  incorporated  herein by
                  reference.

(3)(b)            Amended and  Restated  Bylaws of the Company  filed as Exhibit
                  4(ii) to the  Registrant's  Current  Report  on Form 8-K dated
                  July 29, 1997 and incorporated herein by reference.

(4)(a)            Indenture  dated  as of May 29,  1998  between  LES,  Inc.  (a
                  subsidiary   of  the   Registrant),   Registrant,   subsidiary
                  guarantors of the Registrant and The Bank of Nova Scotia Trust
                  Company of New York,  as trustee  filed as Exhibit 4(b) to the
                  Registrant's  Form S-4  Registration  Statement No.  333-57587
                  filed June 24, 1998 and incorporated herein by reference.

(4)(b)            First Supplemental Indenture effective as of November 15, 1998
                  among Safety-Kleen Services,  Inc. the Registrant,  SK Europe,
                  Inc. and The Bank of Nova Scotia Trust Company of New York, as
                  trustee filed as Exhibit (4)(e) to the  Registrant's  Form S-4
                  Registration   Statement   No.   filed   July  12,   1999  and
                  incorporated herein by reference.

(4)(c)            Indenture dated as of May 17, 1999 between  Registrant and the
                  Bank of Nova  Scotia  Trust  Company  of New York,  as trustee
                  filed  as  Exhibit  (4)(b)  to  the   Registrant's   Form  S-4
                  Registration   Statement   No.   filed   July  12,   1999  and
                  incorporated herein by reference.

(4)(d)            Registration  Rights  Agreement  dated  as  of  May  17,  1999
                  between Registrant and TD Securities,  NationsBanc  Montgomery
                  Securities  LLC and Raymond James &


                                       34
<PAGE>

                  Associates,  Inc. filed as Exhibit (4)(a) to the  Registrant's
                  Form S-4  Registration  Statement  No.     filed July 12, 1999
                  and incorporated herein by reference.

(4)(e)            Amended  and   Restated   Credit   Agreement   among   Laidlaw
                  Chem-Waste,  Inc.,  Laidlaw  Environmental  Services  (Canada)
                  Ltd.,  Toronto  Dominion  (Texas) Inc.,  The  Toronto-Dominion
                  Bank,  TD  Securities  (USA)  Inc.,  The Bank of Nova  Scotia,
                  NationsBank,  N.A. and The First  National Bank of Chicago and
                  NationsBank,  N.A. as  Syndication  Agent dated as of April 3,
                  1998, filed as Exhibit 4(f) to the Registrant's  Form 10-Q for
                  the quarter ended February 28, 1999, and  incorporated  herein
                  by reference.

(4)(f)            Supplement to the Amended and Restated Credit  Agreement among
                  Laidlaw  Chem-Waste,   Inc.,  Laidlaw  Environmental  Services
                  (Canada)   Ltd.,    Toronto   Dominion   (Texas)   Inc.,   The
                  Toronto-Dominion  Bank, TD Securities  (USA) Inc., The Bank of
                  Nova Scotia, NationsBank,  N.A. and The First National Bank of
                  Chicago and NationsBank, N.A. as Syndication Agent dated as of
                  April 3, 1998,  filed as Exhibit 4(e) to a  subsidiary  of the
                  Registrant's  Form S-4  Registration  Statement No.  333-57587
                  filed June 24, 1998 and incorporated herein by reference.

(4)(g)            Waiver and First  Amendment to the Amended and Restated Credit
                  Agreement  dated as of May 15, 1998 among LES,  Inc.,  Laidlaw
                  Environmental  Services  (Canada) Ltd.,  the Lenders,  Toronto
                  Dominion   (Texas),   Inc.,  The  Toronto  Dominion  Bank,  TD
                  Securities  (USA) Inc., The Bank of Nova Scotia,  NationsBank,
                  N.A.,  The First  National  Bank of Chicago and Wachovia  Bank
                  filed as Exhibit 4(f) to a subsidiary of the Registrant's Form
                  S-4  Registration  Statement No. 333-57587 filed June 24, 1998
                  and incorporated herein by reference.

(4)(h)            Commitment to Increase  Supplement to the Amended and Restated
                  Credit  Agreement  dated as of June 3, 1998 among  LES,  Inc.,
                  Laidlaw  Environmental  Services  (Canada)  Ltd., the Lenders,
                  Toronto Dominion (Texas),  Inc., The Toronto Dominion Bank, TD
                  Securities  (USA) Inc., The Bank of Nova Scotia,  NationsBank,
                  N.A.,  The First  National  Bank of Chicago and Wachovia  Bank
                  filed as Exhibit 4(g) to a subsidiary of the Registrant's Form
                  S-4  Registration  Statement No. 333-57587 filed June 24, 1998
                  and incorporated herein by reference.

(4)(i)            Second  Amendment to the Amended and Restated Credit Agreement
                  dated as of  November  20, 1998 among  Safety-Kleen  Services,
                  Inc.  (formerly  known as LES,  Inc.),  Safety-Kleen  Services
                  (Canada)  Ltd.   (formerly  known  as  Laidlaw   Environmental
                  Services   (Canada)  Ltd.),  the  Lenders,   Toronto  Dominion
                  (Texas),  Inc., The Toronto Dominion Bank, TD Securities (USA)
                  Inc.,  The Bank of Nova Scotia,  NationsBank,  N.A., The First
                  National  Bank of Chicago  and  Wachovia  Bank N.A.,  filed as
                  Exhibit  (4)(j) to the  Registrants  Form 10-Q for the quarter
                  ended February 28, 1999 and incorporated herein by reference.

4)(j)             Waiver and Third  Amendment to the Amended and Restated Credit
                  Agreement dated as of May 6, 1999 among Safety-Kleen Services,
                  Inc. (formerly known as


                                       35
<PAGE>

                  (LES, Inc.),  Safety-Kleen  Services  (Canada) Ltd.  (formerly
                  known as Laidlaw  Environmental  Services  (Canada) Ltd.), the
                  Lenders,  Toronto Dominion (Texas), Inc., The Toronto Dominion
                  Bank,  TD  Securities  (USA)  Inc.,  The Bank of Nova  Scotia,
                  NationsBank,  N.A.  The First  National  Bank of  Chicago  and
                  Wachovia Bank N.A. filed as Exhibit (4)(k) to the Registrant's
                  Form S-4  Registration  Statement  No.     filed July 12, 1999
                  and incorporated herein by reference.

(4)(k)            $350,000,000 5% Subordinated Convertible Pay-In-Kind Debenture
                  due 2009  issued  by  Registrant  on May 15,  1997 to  Laidlaw
                  Transportation,  Inc.  the form of which  was  included  as an
                  appendix to the  Registrant's  Definitive  Proxy  Statement on
                  Form DEF 14A, filed on May 1, 1997 and incorporated  herein by
                  reference.

(4)(l)            Registration Rights   Agreement  dated   May 15, 1997  between
                  Registrant, Laidlaw Transportation,  Inc. and Laidlaw Inc. the
                  form of which was included as an appendix to the  Registrant's
                  Definitive  Proxy  Statement  on Form DEF 14A, filed on May 1,
                  1997 and incorporated herein by reference.

(4)(m)            Indenture  dated  as of May 1,  1993  between  the  Industrial
                  Development Board of the Metropolitan  Government of Nashville
                  and Davidson County  (Tennessee) and NationsBank of Tennessee,
                  N.A., filed as Exhibit 4(f) to the Registrant's  Form 10-Q for
                  the Quarter  ended May 31, 1997,  and  incorporated  herein by
                  reference.

(4)(n)            Indenture  of  Trust dated as of  August 1995  between  Tooele
                  County, Utah and West One Bank, Utah, now known as U.S.  Bank,
                  as  Trustee, filed as  Exhibit 4(h) to  the  Registrant's form
                  10-Q for the Quarter ended May 31, 1997, and incorporated
                  herein by reference.

(4)(o)            Indenture  of Trust  dated as of July 1, 1997  between  Carbon
                  County, Utah and U.S. Bank, a national banking association, as
                  Trustee,  filed as Exhibit 4(i) to the Registrant's  Form 10-Q
                  for the Quarter ended May 31, 1997, and incorporated herein by
                  reference.

(4)(p)            Indenture  of Trust  dated as of July 1, 1997  between  Tooele
                  County, Utah and U.S. Bank, a national banking association, as
                  Trustee,  filed as Exhibit 4(j) to the Registrant's  Form 10-Q
                  for the Quarter ended May 31, 1997, and incorporated herein by
                  reference.

(4)(q)            Indenture of Trust dated as of July 1, 1997 between California
                  Pollution  Control  Financing   Authority  and  U.S.  Bank,  a
                  national  banking  association,  as Trustee,  filed as Exhibit
                  4(k) to the  Registrant's  Form 10-Q for the Quarter ended May
                  31, 1997, and incorporated herein by reference.

(4)(r)            Promissory  Note dated May 15, 1997 for  $60,000,000  from the
                  Registrant  to  Westinghouse  Electric  Corporation,  filed as
                  Exhibit  4(n) to the  Registrant's  Form 10-Q for the  Quarter
                  ended May 31, 1997, and incorporated herein by reference.

                                       36
<PAGE>

(4)(s)            Letter  dated May 7, 1999 from  Toronto-Dominion  (Texas) Inc.
                  (as assignee of Westinghouse  Electric Corporation) and agreed
                  to by the  Registrant  and Laidlaw Inc.  amending the terms of
                  the  Promissory  Note  dated May 15,  1997 (as  referenced  in
                  Exhibit  (4)(r)) filed as Exhibit  (4)(t) to the  Registrant's
                  Form S-4  Registration  Statement  No.     filed July 12, 1999
                  and incorporated herein by reference.

(4)(t)            Guaranty  Agreement  dated May 15,  1997 by  Laidlaw  Inc.  to
                  Westinghouse Electric Corporation guaranteeing Promissory Note
                  dated May 15,  1997 (as  referenced  in Exhibit  (4)(r))  from
                  Registrant to  Westinghouse  Electric  Corporation),  filed as
                  Exhibit  4(o) to the  Registrant's  Form 10-Q for the  Quarter
                  ended May 31, 1997, and incorporated herein by reference.

(4)(u)            Escrow  Agreement  dated  as  of  May  17,  1999  between  the
                  Registrant  and the Bank of Nova Scotia  Trust  Company of New
                  York, as trustee,  filed as Exhibit (4)(c) to the Registrant's
                  Form S-4  Registration  Statement  No.     filed July 12, 1999
                  and incorporated herein by reference.

(4)(v)            Other   instruments   defining   the   rights  of  holders  of
                  nonregistered  debt of the  Registrant  have been omitted from
                  this exhibit list because the amount of debt authorized  under
                  any such instrument does not exceed 10% of the total assets of
                  the Registrant and its subsidiaries.  The Registrant agrees to
                  furnish a copy of any such  instrument to the Commission  upon
                  request.
(10)(a)           Agreement and Plan of Merger dated as of March 16, 1998 by and
                  among  Registrant,  LES  Acquisition,  Inc., and  Safety-Kleen
                  Corp.  included as Annex A of  Safety-Kleen's  Revised Amended
                  Prospectus on Form 14D-9 filed as Exhibit 62 to Safety-Kleen's
                  Amendment  No. 28 to  Schedule  14-9A on March 17,  1998,  and
                  incorporated herein by reference.

(10)(b)           Stock  Purchase   Agreement  between   Westinghouse   Electric
                  Corporation (Seller) and Rollins Environmental  Services, Inc.
                  (Buyer) for National Electric,  Inc. dated March 7, 1995 filed
                  as Exhibit 2 to the  Registrant's  Current  Report on Form 8-K
                  filed on June 13, 1995 and incorporated herein by reference.

(10)(c)           Second Amendment to Stock Purchase Agreement (as referenced in
                  Exhibit (10)(b) above),  dated May 15, 1997 among Westinghouse
                  Electric Corporation, Rollins Environmental Services, Inc. and
                  Laidlaw Inc., filed as Exhibit 4(m) to the  Registrant's  Form
                  10-Q for the  Quarter  ended May 31,  1997,  and  incorporated
                  herein by reference.

(10)(d)           Rollins  Environmental  Services,  Inc. 1982  Incentive  Stock
                  Option  Plan  filed  with  Amendment  No.  1 to the  Company's
                  Registration  Statement No. 2-84139 on Form S-1 dated June 24,
                  1983 and incorporated herein by reference.

(10)(e)           Rollins  Environmental  Services,  Inc. 1993 Stock Option Plan
                  filed  with  the  Company's  Proxy  Statement  for the  Annual
                  Meeting of Shareholders held January


                                       37
<PAGE>
                  28, 1994 and incorporated herein by reference.

(10)(f)           Registrant's  1997 Stock Option Plan,  filed as Exhibit 4.4 to
                  the Company's Registration Statement No. 333-41859 on Form S-8
                  dated December 10, 1997 and incorporated herein by reference.

(10)(g)           Registrant's  Director's  Stock Option Plan,  filed as Exhibit
                  4.5 to the Company's  Registration  Statement No. 333-41859 on
                  Form S-8 dated  December 10, 1997 and  incorporated  herein by
                  reference.

(10)(h)           Stock  Purchase  Agreement  dated  February  6, 1997 among the
                  Registrant,  Laidlaw Inc.,  and Laidlaw  Transportation,  Inc.
                  included as an appendix to the Definitive  Proxy  Statement on
                  Form DEF 14A filed on May 1, 1997 and  incorporated  herein by
                  reference.

(10)(i)           Corporate  Incentive  Plan  for  fiscal  year  1999,  filed as
                  Exhibit (10)(i) to the Registrant's  Form 10-Q for the quarter
                  ended November 30, 1998 and incorporated herein by reference.

(10)(j)           Operations  Management  Incentive  Plan for  fiscal  year 1999
                  filed as Exhibit (10)(j) to the Registrant's Form 10-Q for the
                  quarter  ended  November 30, 1998 and  incorporated  herein by
                  reference.

(10)(k)           Registrant's U.S. Supplemental Executive Retirement Plan filed
                  as  Exhibit  10(g) to the  Registrant's  10-Q for the  quarter
                  ended November 30, 1997, and incorporated herein by reference.

(10)(l)           Form of Change of Control Agreement  LES-A1,  filed as Exhibit
                  10(k) to the  Registrant's  10-K for the year ended August 31,
                  1998, and incorporated herein by reference.

(10)(m)           Form of Change of Control Agreement LES-B-1,  filed as Exhibit
                  10(l) to the  Registrant's  10-K for the year ended August 31,
                  1998, and incorporated herein by reference.

(10)(n)           Form of Change of Control Agreement  LES-C1,  filed as Exhibit
                  10(m) to the  Registrant's  10-K for the year ended August 31,
                  1998, and incorporated herein by reference.

(10)(o)           Securities  Purchase Agreement dated April 19, 1999, among the
                  Registrant,  Laidlaw  Inc. and Laidlaw  International  Finance
                  Corporation  filed as Exhibit (10)(o) to the Registrant's Form
                  S-4  Registration  Statement  No.       filed  July  12,  1999
                  and incorporated herein by reference.

(11)              Statement of Computation of Per Share Earnings

                                       38
<PAGE>

(12)              Statement Re: Computation of Ratios

(27)              Financial Data Schedule.

                                       39