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                                                                    EXHIBIT 3.12

                          COMMONWEALTH OF PENNSYLVANIA
                               DEPARTMENT OF STATE
                               CORPORATION BUREAU

  ARTICLES
     OF
INCORPORATION

     In compliance with the requirements of the Business Corporation Law,
approved the 5th day of May, A.D. 1933, P.L., 364, as amended, the undersigned,
all of whom are of full age* desiring that they may be incorporated as a
business corporation, do hereby certify:

1.   The name of the Corporation is:

     R & A Bender, Inc.

2.   The location and post office address of its initial registered office in
     this Commonwealth is:

        Pleasant Hall               Letterkenny Township           Franklin
- -----------------------------   ----------------------------   ----------------
           STREET                                                   COUNTY

3.   The purpose or purposes of the corporation which shall be organized under
     this Act are as follows:(**)

       To operate a refuge collection business, to operate a school bus service
       and to engage in and do any lawful act concerning any or all lawful
       businesses for which corporations may be incorporated in the Commonwealth
       of Pennsylvania under the Act of May 5, 1933, P. L. 364, as amended.

4.   The term of its existence is: Perpetual

5.   The aggregate number of shares which the corporation shall have authority
     to issue is:(***) 50,000 shares of Common stock with a par value of $1.00

     (*)   ONE OR MORE CORPORATIONS OR NATURAL PERSONS OF FULL AGE MAY
           INCORPORATE A BUSINESS CORPORATION UNDER THE PROVISIONS OF THIS ACT.

     (**)  IT SHALL NOT BE PERMISSIBLE OR NECESSARY TO SET FORTH ANY POWERS
           ENUMERATED IN SECTION 302 OF THE ACT.

     (***) THERE SHOULD BE SET FORTH THE NUMBER AND PAR VALUE OF ALL SHARES
           HAVING PAR VALUE: THE NUMBER OF SHARES WITHOUT PAR VALUE: AND THE
           STATED CAPITAL APPLICABLE THERETO. IF THE SHARES ARE TO BE DIVIDED
           INTO CLASSES, A DESCRIPTION OF EACH CLASS AND A STATEMENT OF THE
           PREFERENCES, QUALIFICATIONS, LIMITATIONS, RESTRICTIONS, AND THE
           SPECIAL OR RELATIVE RIGHTS GRANTED TO, OR IMPOSED UPON, THE SHARES OF
           EACH CLASS.

FILING FEE -- $40.00

NOTE: Excise Tax at the rate of 1/5th of 1% ($2.00 per $1,000) will be due and
payable at the time of filing of the Articles, computed by multiplying the
number of authorized shares having par value by their par value, or if shares of
no par stock are authorized, then on the stated capital applicable thereto as
well.

ONLY A CLEARLY LEGIBLE ORIGINAL SHOULD BE SUBMITTED. SIGNATURES SHOULD BE IN
BLACK INK

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6.   The names and addresses of each of the first directors, who shall serve
     until the first annual meeting are:

<Table>
<Caption>
       NAME                                             ADDRESS
                                          (Including street and number, if any)
                                       
Richard G. Bender                         Pleasant Hall
                                          Letterkenny Township, Pa.

Alice Fields Bender                       Pleasant Hall
                                          Letterkenny Township, Pa.
</Table>

7.   The names and addresses of each of the incorporators and the number and
     class of shares subscribed by each are:

<Table>
<Caption>
                                      ADDRESS
      NAME                (Including street and number, if any)            NUMBER AND CLASS OF SHARES
                                                                     
Richard G. Bender         Pleasant Hall                                    5,000      Common
                          Letterkenny Township, Pa.

Alice Fields Bender       Pleasant Hall                                    5,000      Common
                          Letterkenny Township, Pa.
</Table>

IN TESTIMONY WHEREOF, the incorporators have signed and sealed these Articles of
Incorporation this 18th day of June, 1969

/s/ Richard Bender               (Seal)                                   (Seal)
- ------------------------------            -----------------------------
/s/ Alice Bender                 (Seal)                                   (Seal)
- ------------------------------            -----------------------------
                                 (Seal)                                   (Seal)
- ------------------------------            -----------------------------

Approved and filed in the Department of State on the 24th day of April A.D. 1970


                                           /s/
                                           -------------------------------------
                                               Secretary of the Commonwealth

NOTE:  The Articles must be accompanied with registry statement, executed in
       triplicate, in the form prescribed by Section 206-B of the Act -- all of
       which should be signed by an incorporator, as such.

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                          COMMONWEALTH OF PENNSYLVANIA
                               DEPARTMENT OF STATE
                               CORPORATION BUREAU

     In compliance with the requirements of section 806 of the Business
Corporation Law, act of May 5, 1933 (P. L. 364)(13 P. S. Section 1806), the
undersigned corporation, desiring to amend its Articles, does hereby certify
that:

1.   The name of the corporation is:

                               R & A BENDER, INC.

2.   The location of its registered office in this Commonwealth is (the
     Department of State is hereby authorized to correct the following statement
     to conform to the records of the Department):

P.O. Box 42
Pleasant Hall  17246

3.   The statute by or under which it was incorporated is:

Act of May 5, 1933 as amended

4.   The date of its Incorporation is:

4-24-1970

5.   (Check, and if appropriate, complete one of the following):

/ /  The meeting of the share holders of the corporation at which the amendment
     was adopted was held at the time and place and pursuant to the kind and
     period of notice herein stated.

     Time: The ____________  day of  _________ 19__

     Place: ____________________________________________________________________

     Kind and period of notice: ________________________________________________

/X/  The amendment was adopted by a consent in writing, setting forth the action
     so taken, signed by all of the shareholders entitled to vote thereon and
     filed with the Secretary of the Corporation.

6.   At the time of the action of shareholders:

     (a)   The total number of shares outstanding was:

           10,000
     ---------------------------------------------------------------------------

     (b)   The number of shares entitled to vote was:

           10,000
     ---------------------------------------------------------------------------

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7.   In the action taken by the shareholders:

     (a)   The number of shares voted in favor of the amendment was:

           10,000
     ---------------------------------------------------------------------------

     (a)   The number of shares voted against the amendment was:

           0
     ---------------------------------------------------------------------------

8.   The amendment adopted by the shareholders, set forth in full, is as
     follows:

     Paragraph 5 of the Articles of Incorporation is amended to read as follows:

     5.    The aggregate number of shares which the corporation shall have
           authority to issue is:

     a.    25,000 shares of Class A-Voting-Stock with a par value of $1.00 per
           share.

     b.    25,000 shares of Class B-Non-Voting Stock with a par value of $1.00
           per share.

       IN TESTIMONY WHEREOF, the undersigned corporation has caused these
Articles of Amendment to be signed by a duly authorized officer and its
corporate seal, attested by another such officer, to be hereunto affixed this
9th day of December 1985.

Attest                                                  R & A BENDER, INC.

                                            By:      /s/ Richard Bender
                                                --------------------------------
            (Signatures)                                (Signature)
          /s/ Alice Bender
- ------------------------------------        ------------------------------------
             Secretary                                   President

(Corporate Seal)

INSTRUCTIONS FOR COMPLETION OF FORM

A.  Any necessary copies of Form DSCB: 17.2 (Consent to Appropriation of Name)
    or Form DSCB:17.3 (Consent to Use of Similar Name) shall accompany Articles
    of Amendment effecting a change of name.

B.  Any necessary governmental approvals shall accompany this form.

C.  Where action is taken by partial written consent pursuant to the Articles,
    the second alternate of Paragraph 5 should be modified accordingly.

D.  If the shares of any class were entitled to vote as a class, the number of
    shares of each class so entitled and the number of shares of common stock
    entitled to vote should be set forth in Paragraph 6(b).

E.  If the shares of any class were entitled to vote as a class, the number of
    shares of such class and the number of shares of all other classes voted for
    and against such amendment respectively should be set forth in
    Paragraphs 7(a) and 7(b).

F.  BCI 1807 (15 P. S. Section 1807) requires that the corporation shall
    advertise its intention to file or the filing of Articles of Amendment.
    Proof of publication of such advertising should not be delivered to the
    Department but should be filed with the minutes of the corporation.

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Microfilm Number ____________    Filed with the Department of State on _________

Entity Number ___________        __________________________________________
                                        Secretary of the Commonwealth

               ARTICLES OF AMENDMENT-DOMESTIC BUSINESS CORPORATION
                             DSCB: 15.1915 (Rev 90)

     In compliance with the requirements of 15 Pa.C.S. Section 1915 (relating to
articles of amendment, the undersigned business corporation, desiring to amend
its Articles, hereby states that:

1.   The name of the corporation is: R & A BENDER, INC.
                                     -------------------------------------------

2.   The (a) address of this corporation's current registered office in this
     Commonwealth or (b) name or its commercial re-registered office provider
     and the county of venue is (the Department is hereby authorized to correct
     the following information to conform to the records of the Department):

     (a)   Letterkenny Township, P.O. Box 42, Pleasant Hall, PA Franklin
           ---------------------------------------------------------------------
           Number and Street       City           State   Zip            County

     (b)   _____________________________________________________________________
           Name of Commercial Registered Office Provider                 County

For a corporation represented by a commercial registered office provider, the
county in (b) shall be deemed the county in which the corporation is located for
venue and official publication purposes.

3.   The statute by or under which it was incorporated is: Act of May 5, 1933
                                                           ---------------------
                                                           as amended
                                                           ---------------------

4.   The date of its incorporation is: April 24, 1970
                                       -----------------------------------------

5.   (Check, and if appropriate complete, one of the following):

     /X/   The amendment shall be effective upon filing these Articles of
           Amendment in the Department of State.

     / /   The amendment shall be effective on ______________ at _______________
                                                    Date               Hour

6.   (Check one of the following):

     / /   The amendment was adopted by the shareholders (or members) pursuant
           to 15 Pa.C.S. Section 1914(a) and (b).

     /X/  The amendment was adopted by the board of directors pursuant to 15
          Pa.C.S. Section 1914 (c)

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7.   (Check, and if appropriate complete, one of the following):

     /X/   The amendment adopted by the corporation, set forth in full, is as
           follows:

           Paragraph 1 of the Articles of Incorporation are amended to read as
           follows:
           1.   The name of the Corporation shall be IESI PA BLUE RIDGE LANDFILL
                CORPORATION
           2.   The Registered office address is changed to CT Corporation
                System, Philadelphia county

     / /   The amendment adopted by the corporation is set forth in full in
           Exhibit A attached hereto and made a part hereof.

8.   (Check if the amendment restates the Articles):

     / /   The restated Articles of Incorporation supersede the original
           Articles and all amendments thereto.

       IN TESTIMONY WHEREOF, the undersigned corporation has caused these
Articles of Amendment to be signed by a duly authorized officer thereof this 9th
day of July 1999

                                    IESI PA Blue Ridge Landfill Corporation
                                    -------------------------------------------
                                               (Name of Corporation)

                                    By:          /s/ Jeffrey J. Keenan
                                        ----------------------------------------
                                                      (Signature)

                                    TITLE:       Chairman
                                           -------------------------------------