As filed with the Securities and Exchange Commission on March 5, 2004

                                                       Registration No. 33-20952

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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                              ---------------------

                        POST-EFFECTIVE AMENDMENT NO. 2 TO
                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                              ---------------------


                           COVANTA ENERGY CORPORATION
                           --------------------------
             (Exact Name of Registrant as Specified in its Charter)


                 Delaware                                13-5549268
                 --------                                ----------
     (State or Other Jurisdiction of        (I.R.S. Employer Identification No.)
      Incorporation or Organization)

                       40 Lane Road, Fairfield, N.J. 07004
                       -----------------------------------
               (Address of Principal Executive Offices) (Zip Code)


                 OGDEN ALLIED SERVICES SAVINGS AND SECURITY PLAN
                 -----------------------------------------------
                            (Full Title of the Plan)



                               Timothy J. Simpson
        Vice President, Associate General Counsel and Associate Secretary
                       40 Lane Road, Fairfield, N.J. 07004
                       -----------------------------------
                     (Name and Address of Agent For Service)

                                 (973) 882-9000
                                 --------------
          (Telephone Number, Including Area Code, of Agent For Service)

                                    Copy to:
                              Joseph A. Tato, Esq.
                     LeBOEUF, LAMB, GREENE & MacRAE, L.L.P.
                              125 West 55th Street
                               New York, NY 10019
                                 (212) 424-8000

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                          DE-REGISTRATION OF SECURITIES

         On March 30, 1988, the Registrant registered 980,000 shares of its
common stock, $0.50 par value per share ("Common Stock"), and an indeterminate
amount of Profit Sharing Plan Units reserved for issuance under the Registrant's
Ogden Allied Services Savings and Security Plan (the "Plan"): such shares were
registered on a Registration Statement on Form S-8, Registration No. 33-20952,
as amended by Amendment No. 1 thereto dated April 15, 1988, both filed with the
Securities and Exchange Commission (the "Registration Statement"). Subsequently,
the Plan was renamed and eventually merged into the Covanta Energy Savings Plan.
Through the filing of this Post-Effective Amendment No. 2 to the Registration
Statement, the Registrant hereby deregisters any and all remaining unissued
shares of Common Stock and Profit Sharing Plan Units covered by the Registration
Statement, with such de-registration to be effective immediately upon the filing
of this Post Effective Amendment No. 2 to the Registration Statement.

Item 8.           Exhibits

Exhibit No.

24.1           Power of Attorney of George L. Farr; Anthony J. Bolland; Norman
               G. Einspruch; Jeffrey F. Friedman; Scott Mackin; Craig G.
               Matthews; Homer A. Neal; Robert E. Smith; Joseph A. Tato; Helmut
               Volcker; Robert R. Womack




                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this
Post-Effective Amendment No. 2 to the Registration Statement on Form S-8 to be
signed on its behalf by the undersigned, thereunto duly authorized, in the City
of Fairfield, State of New Jersey, on March 5, 2004.

                                          COVANTA ENERGY CORPORATION

                                          By: /s/ Anthony J. Orlando
                                              ----------------------------------
                                              Anthony J. Orlando
                                              President, Chief Executive Officer
                                              and Principal Financial Officer


         Pursuant to the requirements of the Securities Act of 1933, this
Post-Effective Amendment No. 2 to the Registration Statement has been signed by
the following persons in the capacities and on the date indicated:


Signature                        Title                                 Date
- ---------                        -----                                 ----
                                                                 
/s/ Anthony J. Orlando           President, Chief Executive Officer    March 5, 2004
- ------------------------         and Principal Financial Officer
Anthony J. Orlando

/s/ James Reddington             Controller                            March 5, 2004
- ------------------------
James Reddington

/s/ George L. Farr*              Chairman of the Board of Directors    March 5, 2004
- ------------------------
George L. Farr

/s/ Anthony J. Bolland*          Director                              March 5, 2004
- ------------------------
Anthony J. Bolland

/s/ Norman G. Einspruch*         Director                              March 5, 2004
- ------------------------
Norman G. Einspruch

/s/ Jeffrey F. Friedman*         Director                              March 5, 2004
- ------------------------
Jeffrey F. Friedman

                                  Director                              March 5, 2004
- ------------------------
Veronica M. Hagen

/s/ Scott Mackin*                Director                              March 5, 2004
- ------------------------
Scott Mackin

/s/ Craig G. Matthews*           Director                              March 5, 2004
- ------------------------
Craig G. Matthews

 /s/ Homer A. Neal*              Director                              March 5, 2004
- ------------------------
Homer A. Neal

/s/ Robert E. Smith*             Director                              March 5, 2004
- ------------------------
Robert E. Smith

/s/ Joseph A. Tato*              Director                              March 5, 2004
- ------------------------
Joseph A. Tato

/s/ Helmut F.O. Volcker*         Director                              March 5, 2004
- ------------------------
Helmut F.O. Volcker

/s/ Robert R. Womack*             Director                             March 5, 2004
- ------------------------
Robert R. Womack


*  Pursuant to a Power of Attorney filed as an exhibit hereto.

         Pursuant to the requirements of the Securities Act of 1933, the Ogden
Allied Services Savings and Securities Plan has duly caused this Registration
Statement to be signed on its behalf of the undersigned members of the
Administrative Committee of the Ogden Allied Services Savings and Securities
Plan thereunto duly authorized, in the City of Fairfield, State of New Jersey on
the 5th day of March, 2004.


                                          ADMINISTRATIVE COMMITTEE

                                          By:
                                             -----------------------------------

                                             -----------------------
                                             Plan Administrator