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                                                                     Exhibit 5.1

                    [LETTERHEAD OF MCDERMOTT, WILL & EMERY]



                                November 20, 2002




IESI Corporation
6125 Airport Freeway
Suite 202
Haltom City, Texas 76117

         RE:      Registration Statement on Form S-4 Relating to $150,000,000
                  Aggregate Principal Amount of 10-1/4% Senior Subordinated
                  Notes due 2012

Ladies and Gentlemen:

                  We have acted as special counsel to IESI Corporation, a
Delaware corporation (the "Company"), in connection with the preparation and
filing with the U.S. Securities and Exchange Commission (the "Commission")
under the Securities Act of 1933, as amended (the "Securities Act"), of a
Registration Statement on Form S-4 (the "Registration Statement"), which
includes a form of prospectus (the "Prospectus") relating to the proposed
exchange by the Company of $150,000,000 aggregate principal amount of its
10-1/4% Senior Subordinated Notes due 2012, which are to be registered under
the Act (the "Exchange Notes"), for a like amount of its outstanding,
unregistered 10-1/4% Senior Subordinated Notes due 2012 issued on June 12,
2002 (the "Outstanding Notes"). The Exchange Notes will be guaranteed as to
the payment of principal and interest thereon (such guarantees, the
"Subsidiary Guarantees" and, collectively, with the Exchange Notes, the
"Securities") by each of the entities listed on SCHEDULE A hereto (each, a
"Subsidiary Guarantor" and, collectively, the "Subsidiary Guarantors"). The
Securities will be issued pursuant to an indenture, dated as of June 12,
2002, as supplemented (the "Indenture"), among the Company, the Subsidiary
Guarantors named therein and The Bank of New York, as trustee (the "Trustee").

                  In rendering the opinions set forth below, we have examined
and relied on originals or copies of the Registration Statement, Indenture, form
of Exchange Note and such other records, documents, certificates and instruments
as we have deemed necessary or appropriate as a basis for the opinions set forth
below.

                  In our examination, we have assumed the genuineness of all
signatures, including endorsements, the legal capacity of all natural persons,
the authenticity of all documents

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submitted to us as originals, the conformity to original documents of all
documents submitted to us as certified or photostatic copies and the
authenticity of the originals of such copies. With regard to factual matters,
we have been provided with, and with your consent have relied (without
independent verification) upon, representations, certificates and statements
of the Company and the Subsidiary Guarantors and their respective officers
and other representatives and of public officials.

                  For purposes of the opinions set forth herein, we have
assumed that: (i) the Trustee is and has been duly organized, validly
existing and in good standing under the laws of its jurisdiction of
organization and is duly qualified to engage in the activities contemplated
by the Indenture; (ii) the Indenture has been duly authorized, executed and
delivered by, and constitutes the legal, valid and binding obligation of, the
Trustee, enforceable against the Trustee in accordance with its terms; (iii)
the Trustee is in compliance, generally and with respect to acting as a
trustee under the Indenture, with all applicable laws and regulations; (iv)
the Trustee had and has the requisite organizational and legal power and
authority to perform its obligations under the Indenture; and (v) the
Exchange Notes will be duly authenticated by the Trustee in the manner
provided in the Indenture.

                  Members of this firm are admitted to the bar of the State
of New York and we express no opinion as to the laws of any jurisdiction
other than the General Corporation Law of the State of Delaware, applicable
provisions of the Delaware Constitution, reported judicial decisions
interpreting such laws and the laws of the State of New York. We express no
opinion as to the effect of any federal or state laws regarding fraudulent
transfers or conveyances.

                  Based on the foregoing, and subject to the limitations,
qualifications, exceptions and assumptions set forth herein, we are of the
opinion that:

                           1.       When duly executed by the Company and
                  authenticated by the Trustee in accordance with the Indenture
                  and delivered in exchange for the Outstanding Notes pursuant
                  to the exchange offer described in the Registration Statement,
                  the Exchange Notes will be duly issued and will constitute
                  valid and binding obligations of the Company, enforceable
                  against the Company in accordance with their terms; and

                           2.       Upon the due execution, authentication and
                  issuance of the Exchange Notes in accordance with the
                  Indenture and the delivery of the Exchange Notes in exchange
                  for the Outstanding Notes pursuant to the exchange offer
                  described in the Registration Statement, the Subsidiary
                  Guarantees will constitute valid and binding obligations of
                  the Subsidiary Guarantors, enforceable against the Subsidiary
                  Guarantors in accordance with their terms.

                  The opinions set forth herein are subject in each case to the
qualification that enforcement may be limited by applicable bankruptcy,
insolvency, reorganization, fraudulent conveyance, moratorium or other similar
laws now or hereafter existing affecting creditors' rights generally and by
general principles of equity (regardless of whether enforcement is sought in
equity or at law).

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                  We hereby consent to the filing of this opinion letter as an
exhibit to the Registration Statement and to the reference to our Firm under the
caption "Legal Matters" in the Prospectus. In giving this consent, we do not
hereby admit that we are within the category of persons whose consent is
required under Section 7 of the Securities Act or the rules and regulations of
the Commission thereunder.

                  This opinion letter is limited to the matters expressly set
forth herein and no opinion is implied or may be inferred beyond the matters
expressly so stated. This opinion letter is given as of the date hereof and we
do not undertake any liability or responsibility to inform you of any change in
circumstances occurring, or additional information becoming available to us,
after the date hereof which might alter the opinions contained herein.

                                   Very truly yours,

                                   /s/ McDermott, Will & Emery
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                                   SCHEDULE A



         IESI AR Corporation
         IESI AR Landfill Corporation
         IESI LA Corporation
         IESI LA Landfill Corporation
         IESI MO Corporation
         IESI NJ Corporation
         IESI NJ Recycling Corporation
         IESI NY Corporation
         IESI OK Corporation
         IESI PA Bethlehem Landfill Corporation
         IESI PA Blue Ridge Landfill Corporation
         IESI PA Corporation
         IESI TX Corporation
         IESI TX GP Corporation
         IESI DE Corporation
         IESI DE LP Corporation
         IESI TX Landfill LP
         Total Waste Systems, Inc.
         TWS, Inc.
         TWS Of Southwestern Oklahoma, Inc.
         Ervin's Trash Services, Inc.
         Grand Lake Sanitation, Inc.
         TWS Of Caddo County, Inc.
         Center Point Disposal, Inc.
         AMD Inc.
         Enviroclean Systems, Inc.
         Best Disposal Service, Inc.
         Central Louisiana Waste, LLC
         WaCo Land Holding, Inc.