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                                                                     EXHIBIT 3.1

                  SECOND RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                             WASTE MANAGEMENT, INC.


         Waste Management, Inc., a corporation organized and existing under the
laws of the State of Delaware (the "Corporation"), hereby certifies as follows:

1. The name of the Corporation is Waste Management, Inc., and the name under
which the Corporation was originally incorporated is USA Waste Services, Inc.
The date of filing of its original Certificate of Incorporation with the
Secretary of State was April 28, 1995.

2. This Second Restated Certificate of Incorporation restates and integrates and
further amends the Restated Certificate of Incorporation of this Corporation by
amending Article Ninth to provide for the election of directors annually.

3. The text of the Restated Certificate of Incorporation as amended or
supplemented heretofore is further amended hereby to read as herein set forth in
full:

         First: The name of the Corporation is "Waste Management, Inc."

         Second: The registered office of the Corporation in the State of
         Delaware is located at Corporation Trust Center, 1209 Orange Street in
         the City of Wilmington, County of New Castle. The name and address of
         its registered agent is The Corporation Trust Company, Corporation
         Trust Center, 1209 Orange Street, Wilmington, Delaware 19801.

         Third: The nature of the business, objects and purposes to be
         transacted, promoted or carried on by the Corporation is:

                  To engage in any lawful activity for which corporations may be
         organized under the General Corporation Law of Delaware.

         Fourth: The total number of shares of capital stock which the
         Corporation shall have authority to issue is one billion, five hundred
         and ten million (1,510,000,000), divided into one billion, five hundred
         million (1,500,000,000) shares of Common Stock of the par value of one
         cent ($0.01) per share and ten million (10,000,000) shares of Preferred
         Stock of the par value of one cent ($0.01) per share.

                  A. No holder of Common Stock or Preferred Stock of the
                  Corporation shall have any pre-emptive, preferential, or other
                  right to purchase or subscribe for any shares of the unissued
                  stock of the Corporation or of any stock of the Corporation to
                  be issued by reason of any increase of the authorized capital
                  stock of the Corporation or of the number of its shares,



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                  or of any warrants, options, or bonds, certificates of
                  indebtedness, debentures, or other securities convertible into
                  or carrying options or warrants to purchase stock of the
                  Corporation or of any stock of the Corporation purchased by it
                  or its nominee or nominees or other securities held in the
                  treasury of the Corporation, whether issued or sold for cash
                  or other consideration or as a dividend or otherwise other
                  than, with respect to Preferred Stock, such rights, if any, as
                  the Board of Directors in its discretion from time to time may
                  grant and at such price as the Board of Directors in its
                  discretion may fix.

                  B. The holders of Common Stock shall have the right to one
                  vote per share on all questions to the exclusion of all other
                  classes of stock, except as by law expressly provided, as
                  otherwise herein expressly provided or as contained within a
                  certificate of designation, with respect to the holders of any
                  other class or classes of stock.

                  C. The Board of Directors is authorized, subject to
                  limitations prescribed by law, by resolution or resolutions to
                  provide for the issuance of shares of Preferred Stock in
                  series, and by filing a certificate pursuant to the applicable
                  law of the State of Delaware, to establish from time to time
                  the number of shares to be included in each such series, and
                  to fix the designation, powers, preferences, and rights of the
                  shares of each such series and the qualifications, limitations
                  or restrictions thereof. The authority of the Board with
                  respect to each series shall include, but not be limited to,
                  determination of the following:

                           (1) The number of shares constituting that series and
                  the distinctive designation of that series;

                           (2) The dividend rights and dividend rate on the
                  shares of that series, whether dividends shall be cumulative,
                  and, if so, from which date or dates, and the relative rights
                  of priority, if any, of payment of dividends on shares of that
                  series;

                           (3) Whether that series shall have voting rights, in
                  addition to the voting rights provided by law, and, if so, the
                  terms of such voting rights;

                           (4) Whether that series shall have conversion or
                  exchange privileges, and, if so, the terms and conditions of
                  such conversion or exchange including provision for adjustment
                  of the conversion or exchange rate in such events as the Board
                  of Directors shall determine;

                           (5) Whether or not the shares of that series shall be
                  redeemable, and, if so, the terms and conditions of such
                  redemption, including the date or dates upon or after which
                  they shall be redeemable,



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                  and the amount per share payable in cash on redemption, which
                  amount may vary under different conditions and at different
                  redemption dates;

                           (6) Whether that series shall have a sinking fund for
                  the redemption or purchase of shares of that series, and, if
                  so, the terms and amount of such sinking fund;

                           (7) The rights of the shares of that series in the
                  event of voluntary or involuntary liquidation, dissolution or
                  winding up of the Corporation, and the relative rights of
                  priority, if any, of payment of shares of that series;

                           (8) Any other relative rights, preferences and
                  limitations of that series; or

                           (9) Any or all of the foregoing terms.

                  D. Except where otherwise set forth in the resolution or
                  resolutions adopted by the Board of Directors of the
                  Corporation providing for the issue of any series of Preferred
                  Stock created thereby, the number of shares comprising such
                  series may be increased or decreased (but not below the number
                  of shares then outstanding) from time to time by like action
                  of the Board of Directors of the Corporation. Should the
                  number of shares of any series be so decreased, the shares
                  constituting such decrease shall resume the status which they
                  had prior to adoption of the resolution originally fixing the
                  number of shares of such series.

                  E. Shares of any series of Preferred Stock which have been
                  redeemed (whether through the operation of a sinking fund or
                  otherwise), purchased or otherwise acquired by the
                  Corporation, or which, if convertible or exchangeable, have
                  been converted into or exchanged for shares of stock of any
                  other class or classes, shall have the status of authorized
                  and unissued shares of Preferred Stock and may be reissued as
                  a part of the series of which they were originally a part or
                  may be reclassified or reissued as part of a new series of
                  Preferred Stock to be created by resolution or resolutions of
                  the Board of Directors or as part of any other series of
                  Preferred Stock, all subject to the conditions or restrictions
                  adopted by the Board of Directors of the Corporation providing
                  for the issue of any series of Preferred Stock and to any
                  filing required by law.

         Fifth: The Corporation is to have perpetual existence.

         Sixth: Elections of directors need not be by written ballot unless the
         bylaws of the Corporation shall so provide. Meetings of stockholders
         may be held within or without the State of Delaware, as the bylaws may
         provide. The books of the Corporation may be kept (subject to any
         provision contained in the statutes of the



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         State of Delaware) outside the State of Delaware at such place or
         places as may be designated from time to time by the Board of Directors
         or in the bylaws of the Corporation.

         Seventh: No director of the Corporation shall be personally liable to
         the Corporation or its stockholders for monetary damages for breach of
         fiduciary duty as a director, provided that this provision shall not
         eliminate or limit the liability of a director (i) for any breach of
         the director's duty of loyalty to the Corporation or its stockholders,
         (ii) for acts or omissions not in good faith or which involve
         intentional misconduct or a knowing violation of law, (iii) under
         Section 174 of the General Corporation Law of Delaware or any amendment
         thereto or successor provision thereto, or (iv) for any transaction
         from which the director derived an improper personal benefit. If the
         General Corporation Law of Delaware hereafter is amended to authorize
         the further elimination or limitation of the liability of directors,
         then the liability of a director of the Corporation, in addition to the
         limitation on personal liability provided herein, shall be limited to
         the fullest extent permitted by the amended General Corporation Law of
         Delaware. Neither this Second Restated Certificate of Incorporation nor
         any amendment, alteration, or repeal of this Article, nor the adoption
         of any provision of the Second Restated Certificate of Incorporation
         inconsistent with this Article, shall adversely affect, eliminate, or
         reduce any right or protection of a director of the Corporation
         hereunder with respect to any act, omission or matter occurring, or any
         action, suit, or claim that, but for this Article, would accrue or
         arise, prior to the time of such amendment, modification, repeal, or
         adoption of an inconsistent provision. All references in this Article
         to a "director" shall also be deemed to refer to such person or
         persons, if any, who pursuant to a provision of the Second Restated
         Certificate of Incorporation in accordance with subsection (a) of
         Section 141 of the Delaware General Corporation Law, exercise or
         perform any of the powers or duties otherwise conferred or imposed upon
         the Board of Directors by the Delaware General Corporation Law.

         Eighth: This Corporation shall, to the maximum extent permitted from
         time to time under the law of the State of Delaware, indemnify and upon
         request shall advance expenses to any person who is or was a party or
         is threatened to be made a party to any threatened, pending or
         completed action, suit, proceeding or claim, whether civil, criminal,
         administrative or investigative, by reason of the fact that such person
         is or was or has agreed to be a director or officer of this Corporation
         or any of its direct or indirect subsidiaries or while such a director
         or officer is or was serving at the request of this Corporation as a
         director, officer, partner, trustee, employee or agent of any
         corporation, partnership, joint venture, trust or other enterprise,
         including service with respect to employee benefit plans, against
         expenses (including attorney's fees and expenses), judgments, fines,
         penalties and amounts paid in settlement incurred in connection with
         the investigation, preparation to defend or defense of such action,
         suit, proceeding or claim; provided, however, that the foregoing shall
         not require this Corporation to indemnify or advance expenses to any
         person in connection with any action, suit,



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         proceeding, claim or counterclaim initiated by or on behalf of such
         person. Such indemnification shall not be exclusive of other
         indemnification rights arising under any bylaws, agreement, vote of
         directors or stockholders or otherwise and shall inure to the benefit
         of the heirs and legal representatives of such person. Any person
         seeking indemnification under this Article shall be deemed to have met
         the standard of conduct required for such indemnification unless the
         contrary shall be established.

         Ninth:   (A) Except as otherwise provided in this Second Restated
                  Certificate of Incorporation or the bylaws of the Corporation
                  relating to the rights of the holders of any class or series
                  of Preferred Stock, voting separately by class or series, to
                  elect additional directors under specified circumstances, the
                  number of directors of the Corporation shall be as fixed from
                  time to time by, or in the manner provided in, the bylaws of
                  the Corporation. Unless approved by at least two-thirds of the
                  incumbent directors, the number of directors which shall
                  constitute the whole Board of Directors shall be no fewer than
                  three and no more than nine.

                  (B) Commencing with the election of directors at the 2003
                  Annual Meeting of Stockholders, all directors, other than
                  those who may be elected by the holders of any class or series
                  of Preferred Stock voting separately by class or series, shall
                  be elected annually. Notwithstanding the foregoing provision
                  of this Article, each director shall serve until his successor
                  is duly elected and qualified or until his earlier death,
                  resignation or removal.

                  (C) Except as otherwise provided pursuant to the provisions of
                  this Second Restated Certificate of Incorporation or the
                  bylaws of the Corporation relating to the rights of the
                  holders of any class or series of Preferred Stock, voting
                  separately by class or series, to elect directors under
                  specified circumstances, any director or directors may be
                  removed from office at any time, with or without cause but
                  only by the affirmative vote, at any annual meeting or special
                  meeting (as the case may be) of the stockholders, of not less
                  than two-thirds of the total number of votes of the then
                  outstanding shares of capital stock of the Corporation
                  entitled to vote generally in the election of directors,
                  voting together as a single class, but only if notice of such
                  proposal was contained in the notice of such meeting.

                  (D) In the event of any increase or decrease in the authorized
                  number of directors, the newly created or eliminated
                  directorships resulting from such increase or decrease shall
                  be appointed or determined by the Board of Directors. No
                  decrease in the authorized number of directors constituting
                  the Board of Directors shall shorten the term of any incumbent
                  director.



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                  (E) Vacancies in the Board of Directors, however caused, and
                  newly-created directorships shall be filled solely by a
                  majority vote of the directors then in office, whether or not
                  a quorum, and any director so chosen shall hold office until
                  his successor is duly elected and qualified or until his
                  earlier death, resignation or removal.

                  (F) Notwithstanding the foregoing, whenever the holders of any
                  one or more classes or series of Preferred Stock issued by the
                  Corporation shall have the right, voting separately by class
                  or series, to elect directors at an annual or special meeting
                  of stockholders, the election, term of office, filling of
                  vacancies, and other features of such directorships shall be
                  governed by the terms of this Second Restated Certificate of
                  Incorporation applicable thereto, and such directors so
                  elected shall not be divided into classes pursuant to this
                  Article unless expressly provided by such terms.

                  (G) Notwithstanding any other provision of this Second
                  Restated Certificate of Incorporation or the bylaws of the
                  Corporation (and notwithstanding the fact that a lesser
                  percentage may be specified by law, this Second Restated
                  Certificate of Incorporation or the bylaws of the
                  Corporation), the affirmative vote, at any regular meeting or
                  special meeting of the stockholders, of not less than
                  two-thirds of the total number of votes of the then
                  outstanding shares of capital stock of the Corporation
                  entitled to vote generally in the election of directors,
                  voting together as a single class, shall be required to amend
                  or repeal, or to adopt any provision inconsistent with the
                  purpose or intent of, this Article, but only if notice of the
                  proposed alteration or amendment was contained in the notice
                  of such meeting.

         Tenth: In furtherance of, and not in limitation of, the powers
         conferred by statute, the Board of Directors is expressly authorized to
         adopt, amend or repeal the bylaws of the Corporation, or adopt new
         bylaws, without any action on the part of the stockholders; provided,
         however, that no such adoption, amendment or repeal shall be valid with
         respect to bylaw provisions which have been adopted, amended or
         repealed by the stockholders; and further provided, that bylaws adopted
         or amended by the Directors and any powers thereby conferred may be
         amended, altered or repealed by the stockholders.

         Eleventh: The Corporation reserves the right at any time, and from time
         to time, to amend, alter, change, or repeal any provision contained in
         this Second Restated Certificate of Incorporation, and other provisions
         authorized by the laws of the State of Delaware at the time in force
         may be added or inserted, in the manner now or hereafter prescribed by
         law; and all rights, preferences, and privileges of whatsoever nature
         conferred upon stockholders, directors, or any other persons whomsoever
         by and pursuant to this Second Restated Certificate of Incorporation in
         its present form or as hereafter amended are granted subject to the
         rights reserved in this Article; provided, however, that the
         Corporation shall not amend



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         Article Ninth to be effective on a date other than a date on which
         directors are elected.

4. This Second Restated Certificate of Incorporation was duly adopted by vote of
the stockholders in accordance with Section 242 and 245 of the General
Corporation Law of the State of Delaware.

         IN WITNESS WHEREOF, WASTE MANAGEMENT, INC. has caused this Second
Restated Certificate of Incorporation to be signed by David P. Steiner, its
Senior Vice President, General Counsel and Corporate Secretary, this 24th day of
May, 2002.

                                       WASTE MANAGEMENT, INC.



                                       /s/ David P. Steiner
                                       -----------------------------------------
                                       David P. Steiner
                                       Senior Vice President, General Counsel
                                         and Corporate Secretary



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