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                                                                       EXHIBIT 5


                    PAUL, WEISS, RIFKIND, WHARTON & GARRISON
                           1285 AVENUE OF THE AMERICAS
                          NEW YORK, NEW YORK 10019-6064
                                 (212) 373-3000




                                  July 12, 1999




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

                  Registration Statement on Form S-4

Ladies and Gentlemen:

                  In connection with the referenced Registration Statement on
Form S-4 (the "Registration Statement") filed today by Safety-Kleen Corp. (the
"Issuer"), a Delaware corporation, with the Securities and Exchange Commission
(the "SEC") under the Securities Act of 1933, as amended (the "Act"), and the
rules and regulations under the Act, we have been requested to render our
opinion as to the legality of the securities being registered. The Registration
Statement registers under the Act the issuance of the Issuer's 9 1/4% Exchange
Senior Notes due 2009 (the "Exchange Notes"). The Exchange Notes are to be
offered in exchange for the Issuer's outstanding 9 1/4% Senior Notes due 2009
(the "Initial Notes"). The Exchange Notes will be issued by the Issuer under the
Indenture (the "Indenture"), dated as of May 17, 1999, between the Issuer and
The Bank of Nova Scotia Trust Company of New York, as trustee (the "Trustee").
Capitalized terms used and not
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July 12, 1999
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otherwise defined in this letter have the respective meanings given those terms
in the Registration Statement.

                  In connection with this opinion, we have examined originals,
conformed copies or photocopies, certified or otherwise identified to our
satisfaction, of the following documents (collectively, the "Documents"):

                  (i)   the Registration Statement (including its exhibits);

                  (ii)  the Indenture included as Exhibit 4(b) to the
                        Registration Statement;

                  (iii) the proposed form of the Exchange Notes included as
                        Exhibit A- 1 to the Indenture; and

                  (iv)  the Registration Rights Agreement, dated as of May 17,
                        1999, among the Issuer, TD Securities (USA) Inc.,
                        NationsBanc Montgomery Securities LLC and Raymond James
                        & Associates, Inc. (the "Registration Rights
                        Agreement").

In addition, we have examined: (i) those corporate records of the Issuer as we
have considered appropriate; and (ii) those other certificates, agreements and
documents as we deemed relevant and necessary as a basis for the opinions
expressed below.

                  In our examination of the documents and in rendering the
opinions set forth below, we have assumed, without independent investigation,
(i) the genuineness of all signatures, the authenticity of all documents
submitted to us as originals, the conformity of the original documents of all
documents submitted to us as certified, photostatic, reproduced or conformed
copies of validly existing agreements or other
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documents, the authenticity of all the latter documents and the legal capacity
of all individuals who have executed any of the documents which we examined,
(ii) that the Exchange Notes will be issued as described in the Registration
Statement, (iii) that the Indenture was duly authorized, executed and delivered
by the Trustee and is a valid and binding agreement of the Trustee, (iv) that
the Registration Rights Agreement was duly authorized, executed and delivered by
the Initial Purchasers and is a valid and binding agreement of the Initial
Purchasers and (v) that the Exchange Notes will be in substantially the form
attached to the Indenture and that any information omitted from them will be
properly added. We have also relied upon certificates of public officials and
officers of the Issuer.

                  Based on the above, and subject to the stated assumptions,
exceptions and qualifications, we are of the opinion that, when the Exchange
Notes are duly issued, authenticated and delivered in accordance with the terms
of the Indenture and the Registration Rights Agreement, the Exchange Notes will
be legal, valid and binding obligations of the Issuer enforceable against it in
accordance with their terms.

                  Our opinion is subject to the qualification that the
enforceability of the Indenture and the Exchange Notes may be (i) subject to
bankruptcy, insolvency, fraudulent conveyance or transfer, reorganization,
moratorium and other similar laws affecting creditors' rights generally and (ii)
general principles of equity (regardless of whether enforcement is considered in
a proceeding at law or in equity).

                  Our opinion is limited to matters of New York law and the
Delaware General Corporation Law. Please be advised that no member of this firm
is admitted
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to practice in the State of Delaware. Our opinion is rendered only with respect
to the laws, and the rules, regulations and orders under them, which are
currently in effect.

                  We hereby consent to the use of our name in the Registration
Statement and in the prospectus contained in the Registration Statement as it
appears in the caption "Legal Matters" and to the use of this opinion as an
exhibit to the Registration Statement. In giving this consent, we do not admit
that we come within the category of persons whose consent is required by the Act
or by the rules and regulations under the Act.

                                Very truly yours,



                                /s/ Paul, Weiss, Rifkind, Wharton & Garrison
                                PAUL, WEISS, RIFKIND, WHARTON & GARRISON