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                                                                    EXHIBIT 4(c)



                                 AMENDMENT NO. 2

                                       TO

                                RIGHTS AGREEMENT

                                     BETWEEN

                      ROLLINS ENVIRONMENTAL SERVICES, INC.

                                       AND

                         REGISTRAR AND TRANSFER COMPANY


         This Amendment No. 2 dated as of the 30th day of April, 1997 amending
that certain Rights Agreement (the "Rights Agreement") dated as of June 14, 1989
between Rollins Environmental Services, Inc. (the "Company") and Registrar and
Transfer Company (the "Rights Agent").

         WHEREAS, Section 26 to the Rights Agreement provides that as long as
the Rights defined in and created by the Rights Agreement (the "Rights") are
redeemable, the Company may in its sole and absolute discretion, and the Rights
Agent shall if the Company so directs, supplement or amend any provision of the
Rights Agreement without the approval of any holders of the Rights or the Common
Stock of the Company (the "Common Stock"), provided that no such supplement or
amendment shall be made which changes the Redemption Price (as defined in the
Rights Agreement), the Final Expiration Date (as defined in the Rights
Agreement) or the number of shares of Common Stock for which a Right is
exercisable; and

         WHEREAS, pursuant to Amendment No. 1 to the Rights Agreement, the
definition of Acquiring Person in Section 1(a) to the Rights Agreement was
amended such that Westinghouse Electric Corporation, a Pennsylvania corporation
("Westinghouse"), would not be deemed an Acquiring Person under certain
circumstances due to its ownership of the Company's 7.25% Convertible
Subordinated Debentures Due 2005 (the "Securities"); and

         WHEREAS, in connection with a Stock Purchase Agreement dated February
6, 1997 between the Company and Laidlaw Inc., a Canadian corporation
("Laidlaw"), the Company intends to redeem the Securities and issue additional
securities to Laidlaw (the "Additional Securities"); and

         WHEREAS, unless the Rights Agreement is amended, the sale of the
Additional Securities to Laidlaw would result in Laidlaw being an Acquiring
Person (as defined in the Rights Agreement) and result in a Triggering Event (as
defined in the Rights Agreement); and

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         WHEREAS, the Company and the Rights Agent desire to amend the Rights
Agreement as provided herein in order to avoid a Triggering Event;

         NOW THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereby agree as follows:

         1.       Amendment No. 1 Terminated.

                  Amendment No. 1 is hereby terminated and of no further force
                  or effect effective at such time as the Securities are
                  redeemed.

         2.       Amendment to Definition of Acquiring Person.

                  Effective on the date hereof, the following shall be added to
the end of the definition of Acquiring Person in Section 1 (a) to the Rights
Agreement:

                  "Notwithstanding the foregoing, neither Laidlaw Inc., a
         Canadian corporation, nor any Affiliate thereof, shall be deemed to be
         an Acquiring Person as long as this Amendment No. 2 is in effect. The
         Company may, by order of its Board of Directors, make subsequent
         amendments to the Rights Agreement to eliminate or modify this
         Amendment No. 2 at any time."

         3.       Representation and Warranties of the Company.

                  The Company represents and warrants to the Rights Agent that
(i) this Amendment No. 2 is permitted under the terms of the Rights Agreement,
and (ii) this Amendment No. 2 does not change the Redemption Price, the Final
Execution Date or the number of shares of Common Stock for which a Right is
exercisable under the Rights Agreement.

         IN WITNESS WHEREOF, the parties hereto have caused this amendment No. 2
to the Rights Agreement to be duly executed, all as of the day and year first
above written.

                                    Rollins Environmental Services, Inc.


                                    By:          /s/ Klaus Belohoubek
                                         --------------------------------------


                                    Registrar and Transfer Company


                                    By:         /s/ William P. Tatler
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