Document:

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                                                                    EXHIBIT 10.9

                               AGREEMENT TO DEFER
                         CONVERSION OF PREFERRED STOCKS

                  THIS AGREEMENT, entered into on this 2nd day of April, 2003,
is by and among 3CI COMPLETE COMPLIANCE CORPORATION (the "Company"), a Delaware
corporation, WASTE SYSTEMS, INC. ("WSI"), a Delaware corporation, and
STERICYCLE, INC. ("Stericycle"), a Delaware corporation and the owner of 100% of
the capital stock of WSI.

                  WHEREAS, WSI owns 100% of the outstanding shares of the Series
B Convertible Preferred Stock, $1.00 par value ("Series B Preferred Stock"), and
Series C Convertible Preferred Stock, $1.00 par value ("Series C Preferred
Stock" and, together with the Series B Preferred Stock, the "Preferred Stock" or
"Preferred Stocks"), of the Company; and

                  WHEREAS, under the terms of the respective Certificates of
Designation of the Series B and Series C Preferred Stock on file with the
Secretary of State of Delaware, the Preferred Stocks will be automatically
converted into shares of the Common Stock, $0.01 par value ("Common Stock"), of
the Company on April 6, 2003; and

                  WHEREAS, a disagreement has arisen between WSI and Stericycle,
on the one hand, and the Company, on the other hand, regarding the number of
shares of Common Stock, $0.01 par value ("Common Stock") of the Company into
which the Preferred Stock is convertible (the "Conversion Rate"); and

                  WHEREAS, the 269th Judicial District Court of Harris County,
Texas (the "Court") entered a judgment approving the terms of the Settlement
Agreement by and between James T. Rash, et al, and Waste Systems, Inc., 3CI
Complete Compliance Corporation, et al, dated July 17, 1997, under which the
Series B Preferred Stock was approved and issued, and such Court retains
jurisdiction for purposes of enforcing the terms of the Settlement Agreement,
including the terms of the Series B Preferred Stock; and

                  WHEREAS, the Board of Directors of the Company has determined
that it is in the best interests of the Company to file a declaratory judgment
action with such Court and request the Court to determine the Conversion Rate;

                  NOW, THEREFORE, in consideration of the mutual covenants and
agreements set forth herein, and for other good and valuable consideration the
receipt and sufficiency of which is hereby acknowledged by each party, the
parties hereto covenant and agree as follows:

                  1. Deferral of Conversion of Preferred Stocks. Until such time
as a Final Determination (defined hereinafter) occurs setting forth the
appropriate Conversion Rate:

                           a. Stericycle agrees to cause WSI, and WSI agrees,
                  not to exercise any right WSI may have to convert the
                  Preferred Stocks into Common Stock of the Company;

                           b. The Company, WSI and Stericycle agree that no
                  automatic conversion of the Preferred Stocks shall occur or
                  otherwise be deemed to have occurred, notwithstanding any
                  contrary provision of the respective Certificates of
                  Designation governing the Series B Preferred Stock and Series
                  C Preferred Stock; and

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                           c. The Company, WSI and Stericycle agree that the
                  Company shall not be obligated to, and shall not, issue any
                  Common Stock upon conversion of the Preferred Stocks, and that
                  the Company shall be entitled to and shall direct its transfer
                  agent not to record any issue of Common Stock upon, or on
                  account of, conversion of any of the Preferred Stocks.

                  2. Conversion Upon a Final Determination. On the date on which
the Final Determination occurs setting forth the Conversion Rate to be
applicable upon conversion of the Preferred Stocks (the "Settled Conversion
Rate"):

                           a. The Company, WSI and Stericycle agree that the
                  Series B Preferred Stock and the Series C Preferred Stock (i)
                  shall automatically, without any further action on the part of
                  the parties hereto, be converted into that number of shares of
                  Common Stock as shall be calculated based on the Settled
                  Conversion Rate, and (ii) shall be deemed to have been
                  converted for all purposes effective on and as of April 6,
                  2003; and

                           b. The Company shall be obligated to and agrees
                  promptly thereafter to direct its transfer agent to issue that
                  number of shares of Common Stock upon conversion of the
                  Preferred Stocks as shall be calculated based on the Settled
                  Conversion Rate, and to deliver to WSI a certificate or
                  certificates, registered in the name of WSI, representing in
                  the aggregate that number of shares of Common Stock.

                  3. Definition of Final Determination. For purposes of this
Agreement, a "Final Determination" shall mean that date on which the judicial
judgment as to the appropriate Conversion Rate shall become final and
nonappealable, in which case such determination of the Court, or such other
judicial court as may appropriate or necessary, shall become the Settled
Conversion Rate.

                  4. Notices. Any notice, designation, consent, approval or
other communication required or permitted to be given pursuant to the provisions
of this Agreement ("Notice") shall be given in writing and shall be sent by
certified or registered mail, Federal Express, overnight courier, or telecopier,
addressed as follows:

If to the Company:                3CI Complete Compliance Corporation
                                  1517 W. North Carrier Parkway
                                  Grand Prairie, Texas 75050
                                  Attention: Jim Cole, Chief Financial Officer
                                  Tel. No.: (972) 375-0006 #316
                                  Fax No.: (972) 602-0576

If to WSI:                        Waste Systems, Inc.
                                  c/o Stericycle, Inc.
                                  28161 North Keith Drive
                                  Lake Forest, Illinois 60045
                                  Attention: Mr. Frank J. M. ten Brink
                                  Tel. No.: (847) 607-2051
                                  Fax No.: (847) 367-9462

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If to Stericycle:                 Stericycle, Inc.
                                  28161 North Keith Drive
                                  Lake Forest, Illinois 60045
                                  Attention: Mr. Frank J. M. ten Brink
                                  Tel. No.: (847) 607-2051
                                  Fax No.: (847) 367-9462

                  Any party may, by Notice given in accordance with the
provisions of this Section 4, designate any further or different address to
which subsequent Notices shall be sent pursuant to the provisions of this
Agreement. Any Notice shall be deemed to have been given on the date such Notice
shall have been delivered. If such delivery shall be made on a Saturday, Sunday
or holiday, said notice shall be deemed to have been given on the next
succeeding business day.

                  5. Successors and Assigns. This Agreement shall be binding
upon and inure to the benefit of the parties hereto and their respective
successors, legal representatives and assigns, but shall not be assignable by
any party hereto without the written consent of all of the other parties hereto.
Except for the persons specified in the preceding sentence, this Agreement is
not intended to confer on any person not a party hereto any rights or remedies
hereunder.

                  6. Governing Law. This Agreement shall be governed by and
construed under the law of the State of Texas, without giving effect to any
choice of law or other conflict of law provision or rule (whether of the State
of Texas or any other jurisdiction) that would cause the application of the laws
of any jurisdiction other than the State of Texas.

                  7. Further Assurances. Each of the parties hereto shall
hereafter execute and deliver such further instruments and do such further acts
and things as may be required or necessary to carry out the intent and purposes
of this Agreement and which are not otherwise inconsistent with any of the terms
of this Agreement.

                  8. Entire Agreement; Modification or Waiver. This Agreement
embodies the entire agreement and understanding among the parties with respect
to the subject matter hereof and supersedes any and all prior agreements and
understandings relating to the subject matter hereof. No amendment, modification
or waiver of this Agreement or any provision hereof shall be binding or
effective for any purpose unless it is made in a writing signed by all of the
parties hereto. No course of dealing between the parties shall be deemed to
affect or to modify, amend or discharge any provision or term of this Agreement.
No delay by any party to or any beneficiary of this Agreement in the exercise of
any of its or his rights or remedies shall operate as a waiver thereof, and no
single or partial exercise by any party to or any beneficiary of this Agreement
of any such right or remedy shall preclude any other or further exercise
thereof. A waiver of any right or remedy on any one occasion shall not be
construed as a bar to or waiver of any such right or remedy on any other
occasion.

                  9. Counterparts. This Agreement may be executed in two or more
identical counterparts, each of which shall be deemed an original but all of
which together shall constitute one and the same instrument.

                  10. Interpretation. Headings to sections herein are for
convenience of reference only and are not intended to be a part or to affect the
meaning or interpretation of this Agreement. The language used in this Agreement
will be deemed to be the language chosen by the parties hereto to express their
common intent, and no rule of strict construction will be applied against any
party.

                [THE NEXT FOLLOWING PAGE IS THE SIGNATURE PAGE.]

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                  IN WITNESS WHEREOF, the parties have duly executed this
Agreement on the date and year first above written.

                                   3CI COMPLETE COMPLIANCE
                                   CORPORATION

                                   By: /s/ James A. Cole
                                      -----------------------------------------

                                   Its: Chief Financial Officer
                                       ----------------------------------------

                                   WASTE SYSTEMS, INC.

                                   By: /s/ Mark C. Miller
                                      -----------------------------------------

                                   Its: President
                                       ----------------------------------------

                                   STERICYCLE, INC.

                                   By: /s/ Mark C. Miller
                                      -----------------------------------------

                                   Its: President & CEO
                                       ----------------------------------------

                                       4<PAGE>
                                                                     Exhibit 4.1

                                 CERTIFICATE OF
                    VICE CHAIRMAN AND CHIEF FINANCIAL OFFICER
                          AND VICE PRESIDENT, TREASURER
                             AND ASSISTANT SECRETARY
                      PURSUANT TO SECTIONS 201, 301 AND 303
                                OF THE INDENTURE

                                                             Dated: May 19, 2003

            The undersigned, ALAN H. LUND and PAMELA S. HENDRY, do hereby
certify that they are the duly appointed and acting Vice Chairman and Chief
Financial Officer and Vice President, Treasurer and Assistant Secretary,
respectively, of INTERNATIONAL LEASE FINANCE CORPORATION, a California
corporation (the "Company"). Each of the undersigned also hereby certifies,
pursuant to Sections 201, 301 and 303 of the Indenture, dated as of November 1,
2000 (the "Indenture"), between the Company and The Bank of New York, as
Trustee, as amended, that:

            A. There has been established pursuant to resolutions duly adopted
by the Board of Directors of the Company (a copy of such resolutions being
attached hereto as Exhibit B) and by a Special Committee of the Board of
Directors (a copy of such resolutions being attached hereto as Exhibit C) a
series of Securities (as that term is defined in the Indenture) to be issued
under the Indenture, with the following terms:

            1. The title of the Securities of the series is "Medium-Term Notes,
            Series O" (the "Medium-Term Notes").

            2. The limit upon the aggregate principal amount of the Medium-Term
            Notes which may be authenticated and delivered under the Indenture
            (except for Medium-Term Notes authenticated and delivered upon
            registration of, transfer of, or in exchange for, or in lieu of
            other Medium-Term Notes pursuant to Sections 304, 305, 306, 906 or
            1107 of the Indenture) is $2,455,000,000. The Company may, without
            the consent of the Holders of the Medium-Term Notes, issue
            additional notes having the same ranking, interest rate, Stated
            Maturity, CUSIP number and terms as to status, redemption or
            otherwise as Medium-Term Notes that have been previously issued, in
            which event such notes and such previously issued Medium-Term Notes
            shall constitute one issue for all purposes under the Indenture
            including without limitation, amendments and waivers.

            3. The date on which the principal of each of the Medium-Term Notes
            is payable shall be any Business Day (as defined in the forms of
            Global Fixed Rate Note and Global Floating Rate Note attached hereto
            as Exhibit A and incorporated herein by reference) nine months or
            more from the date of issuance as determined from time to time by
            any one of Leslie L. Gonda, Steven F. Udvar-Hazy, Alan H. Lund,
            Pamela S. Hendry or Kurt Schwarz (each a "Designated Person").

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            4. The rate at which each of the Medium-Term Notes shall bear
            interest shall be established by any one Designated Person, and may
            be either a fixed interest rate (which may be zero) (hereinafter, a
            "Fixed Rate Note") or may vary from time to time in accordance with
            one of the interest rate formulas more fully described in Exhibit A
            hereto (hereinafter, a "Floating Rate Note") or otherwise as
            specified by a Designated Person.

            5. Unless otherwise specified by a Designated Person, the date from
            which interest shall accrue for each Medium-Term Note shall be the
            respective date of issuance of each of the Medium-Term Notes.

            6. The interest payment dates on which interest on the Medium-Term
            Notes shall be payable are, in the case of Fixed Rate Notes, April
            15 and October 15, unless otherwise specified by any Designated
            Person, and, in the case of Floating Rate Notes, such dates as
            specified by any Designated Person. The initial interest payment on
            each outstanding Medium-Term Note shall be made on the first
            interest payment date falling at least 15 days after the date the
            Medium-Term Note is issued, unless otherwise specified by any
            Designated Person.

            7. The regular record dates for the interest payable on any Fixed
            Rate Note on any interest payment date shall be April 1 and October
            1, unless otherwise specified by any Designated Person, and the
            regular record dates for the interest payable on any Floating Rate
            Note on any interest payment date shall be on the day 15 calendar
            days prior to any such interest payment date, unless otherwise
            specified by any Designated Person.

            8. Interest on the Fixed Rate Notes shall be computed on the basis
            of a 360-day year of twelve (12) 30-day months. Interest on the
            Floating Rate Notes shall be computed on the basis set forth in
            Exhibit A hereto.

            9. The place or places where the principal (and premium, if any) and
            interest on Medium-Term Notes shall be payable is at the office of
            the Trustee, 101 Barclay Street, Ground Floor Window, New York, New
            York 10286, provided that payment of interest, other than at Stated
            Maturity (as defined in the Indenture) or upon redemption or
            repurchase, may be made at the option of the Company by check mailed
            to the address of the person entitled thereto as such address shall
            appear in the Security Register (as defined in the Indenture) and
            provided further that (i) the Depositary (as designated below), as
            holder of Global Securities (as defined in the Indenture), shall be
            entitled to receive payments of interest by wire transfer of
            immediately available funds, and (ii) a Holder of $10,000,000 or
            more in aggregate principal amount of certificated Medium-Term
            Notes, having identical Interest Payment Dates, shall be entitled to
            receive payments of interest, other than interest due at Stated
            Maturity or upon redemption, by wire transfer in immediately
            available funds to a designated account maintained in the United
            States upon receipt by the Trustee of written instructions from such
            Holder not later than the Regular Record Date for the

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            related Interest Payment Date. Such instructions shall remain in
            effect with respect to payments of interest made to such Holder on
            subsequent Interest Payment Dates unless revoked or changed by
            written instructions received by the Trustee from such Holder;
            provided that any such written revocation or change which is
            received by the Trustee after a Regular Record Date and before the
            related Interest Payment Date shall not be effective with respect to
            the interest payable on such Interest Payment Date.

            10. The date, if any, on which each Medium-Term Note may be redeemed
            at the option of the Company shall be established by any Designated
            Person.

            11. The terms under which any of the Medium-Term Notes shall be
            repaid at the option of the Holder shall be as set forth in the
            forms of the Global Fixed Rate Note and Global Floating Rate Note
            attached hereto and the obligation of the Company, if any, to repay
            any of the Medium-Term Notes at the option of a Holder shall be
            established by any Designated Person.

            12. The Medium-Term Notes shall be issued in fully registered form
            in denominations of $1,000 or any amount in excess thereof which is
            an integral multiple of $1,000.

            13. The principal amount of the Medium-Term Notes shall be payable
            upon declaration of acceleration of the maturity thereof pursuant to
            Section 502 of the Indenture.

            14. The Medium-Term Notes shall be issued as Global Securities under
            the Indenture, unless otherwise specified by any Designated Person,
            and The Depository Trust Company is designated the Depositary under
            the Indenture for the Medium-Term Notes.

            15. The terms of the Medium-Term Notes include the provisions set
            forth in Exhibit A hereto.

            16. If specified by a Designated Person, Medium-Term Notes may be
            issued as Amortizing Notes, Original Issue Discount Notes or Indexed
            Notes, each as described in the Prospectus Supplement dated May 19,
            2003 to the Prospectus dated April 15, 2003 relating to the
            Medium-Term Notes, including any subsequent amendments or
            supplements thereto.

            B. The forms of the Global Fixed Rate Notes and the Global Floating
Rate Notes are attached hereto as Exhibit A.

            C. The Trustee is appointed as Paying Agent (as defined in the
Indenture) and The Bank of New York is appointed as Calculation Agent.

            D. The foregoing form and terms of the Medium-Term Notes have been
established in conformity with the provisions of the Indenture.

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            E. Each of the undersigned has read the provisions of Sections 301
and 303 of the Indenture and the definitions relating thereto and the
resolutions adopted by the Board of Directors of the Company and delivered
herewith. In the opinion of each of the undersigned, he or she has made such
examination or investigation as is necessary to enable him or her to express an
informed opinion as to whether or not all conditions precedent provided in the
Indenture relating to the establishment, authentication and delivery of a series
of Securities under the Indenture, designated as the Medium-Term Notes in this
Certificate, have been complied with. In the opinion of each of the undersigned,
all such conditions precedent have been complied with.

            F. The undersigned Assistant Secretary, by execution of this
Certificate, thereby certifies the actions taken by the Special Committee of the
Board of Directors of the Company in determining and setting the specific terms
of the Medium-Term Notes, and hereby further certifies that attached hereto as
Exhibits A, B, and C respectively, are the forms of certificates representing
the Global Fixed Rate Notes and Global Floating Rate Notes as duly approved by
the Special Committee of the Board of Directors of the Company, a copy of
resolutions duly adopted by the Board of Directors of the Company as of
September 24, 2002 and November 22, 2002 and a copy of resolutions duly adopted
by the Special Committee of the Board of Directors as of December 31, 2002,
January 24, 2003, March 14, 2003 and May 19, 2003, pursuant to which the terms
of the Medium-Term Notes set forth above have been established.

            G. This certificate supersedes in its entirety the Officers'
Certificate, dated March 14, 2003, with respect to the Notes previously
delivered to you.

                  [remainder of page intentionally left blank]

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            IN WITNESS WHEREOF, the undersigned have hereunto executed this
Certificate as of the date first above written.

                                           /s/ Alan H. Lund
                                           -------------------------------------
                                           Alan H. Lund
                                           Vice Chairman and
                                           Chief Financial Officer

                                           /s/ Pamela S. Hendry
                                           -------------------------------------
                                           Pamela S. Hendry
                                           Vice President, Treasurer and
                                           Assistant Secretary

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