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                                                                    Exhibit 3.81

                                    BYLAWS OF
               NEW ENGLAND WASTE SERVICES OF MASSACHUSETTS, INC.

                            ADOPTED NOVEMBER 9, 1999

1. MEETINGS OF STOCKHOLDERS.

        1.1  ANNUAL MEETING. The annual meeting of stockholders shall be held
within six months after the end of the corporation's fiscal year, on any
business day, and at a place and time, as shall be determined by the board of
directors (the "Board"), for the purpose of electing directors and for the
transaction of such other business as may come before the meeting. If no annual
meeting is held as set forth above, a special meeting may be held in lieu
thereof, and any action taken at such meeting shall have the same effect as if
taken at the annual meeting.

        1.2  SPECIAL MEETING. A special meeting of the stockholders may be
called by the President or by resolution of the Board, and a special meeting
shall be called by the Clerk, or in case of the death, absence, incapacity or
refusal of the Clerk, by any other officer, upon the written request (stating
the purpose or purposes of the meeting) of holders of record of ten percent
(10%)of the issued and outstanding stock entitled to vote at such meeting.

        1.3  PLACE OF MEETINGS. Meetings of the stockholders shall be held in
the United States at the place fixed by the Board and stated in the notice of
meeting.

        1.4  NOTICE OF MEETINGS; WAIVER OF NOTICE. Written notice of each
meeting of stockholders shall be given to each stockholder entitled to vote at
the meeting (or otherwise entitled to such notice) by mailing it to him at his
address as it appears in the records of the corporation, postage prepaid, or by
delivering it to him at his residence or usual place of business, at least seven
(7) days before the meeting or such greater length of time as may be required by
law, and shall state the date, time and place of the meeting and the purposes
for which it is called and, unless it is the annual meeting, shall state at
whose direction the meeting is called. Notice need not be given to any
stockholder who submits to the Clerk a signed waiver of notice before or after
the meeting.

        1.5  QUORUM. The presence in person or by proxy of the holders of a
majority of the shares entitled to vote shall constitute a quorum for the
transaction of any business, except as otherwise provided by law or these
Bylaws. In the absence of a quorum any officer entitled to preside at or act as
Clerk of such meeting shall have the power to adjourn the meeting from time to
time until a quorum is present, without further notice other than announcement
at the meeting of the adjourned time and place, except as otherwise provided by
law. At any adjourned meeting at which a quorum is present, any action may be
taken which might have been taken at the meeting as originally called.

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        1.6  VOTING AND PROXIES. Stockholders may attend meetings and vote
either in person, by written proxy dated not more than six months before the
meeting named therein, or by irrevocable proxy as authorized by Massachusetts
law. Proxies shall be filed with the Clerk before being voted at any meeting or
adjournment thereof. A proxy with respect to stock held in the name of two or
more persons shall be valid if signed by one of them unless, at or prior to
exercise of the proxy, the corporation receives a specific written notice to the
contrary from any one of them. Every proxy must be signed by the stockholder or
his attorney-in-fact. Corporate action to be taken by stockholder vote, other
than the election of directors, shall be authorized by a majority of the votes
cast at a meeting of stockholders at which a quorum is present, except as
otherwise provided by law, the Articles of Organization or these Bylaws.
Directors shall be elected in the manner provided in Section 2.1 of these
Bylaws. Voting need not be done by ballot unless requested by a stockholder at a
meeting or ordered by the chairman of the meeting.

        1.7  ACTION BY WRITTEN CONSENT. Action by the stockholders may be taken
without a meeting if a written consent to the action is signed by the holders of
all the outstanding shares entitled to vote thereon and is filed in the
corporation's minute book.

        1.8  INSPECTORS OF ELECTION. The Board shall have the power to appoint
two persons (who need not be stockholders) to act as inspectors of election at
each meeting of stockholders. If there are not two inspectors present, ready and
willing to act, the chairman presiding at any meeting may appoint a temporary
inspector or inspectors to act at such meeting. No candidate for the office of
director shall act as an inspector of any election for directors.

2. BOARD OF DIRECTORS.

        2.1  NUMBER, ELECTION, ELIGIBILITY AND TERM OF DIRECTORS. The Board
shall consist of no less than three directors, except that whenever there are
less than three stockholders the number of directors may equal the number of
stockholders. Until changed by the Board or the stockholders, the number of
directors shall be three. The number of directors may be changed by resolution
of the majority of the entire Board or by vote of the holders of a majority of
the issued and outstanding stock entitled to vote, but no decrease may shorten
the term of any incumbent director. Directors shall be elected at each annual
meeting of stockholders by a plurality of the votes cast. As used in these
Bylaws, "entire Board" means the total number of directors which the
corporation would have if there were no vacancies.

        2.2  QUORUM AND MANNER OF ACTING. A majority of the directors in office
shall constitute a quorum for the transaction of business at any meeting, except
as provided in Section 2.9 of these Bylaws. Action of the Board shall be
authorized by the vote of a majority of the directors present at the time of the
vote if a quorum is present, unless otherwise provided by law, the Articles of
Organization or these Bylaws. In the absence of a quorum, a majority of the

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directors present may adjourn any meeting from time to time until a quorum is
present on notice given as provided in Section 2.7 of these Bylaws.

        2.3  ACTION BY CONFERENCE CALL, ETC. Action of the Board may be taken by
participation in a meeting by means of a conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other at the same time; participation by such means shall
constitute presence in person at the meeting.

        2.4  ACTION BY WRITTEN CONSENT. Action by the directors may be taken
without a meeting if a written consent to the action is signed by all the
directors then in office and filed in the corporation's minute book.

        2.5  ANNUAL MEETING. The annual meeting of the Board, for the election
of officers and consideration of other matters, shall be held either (a) without
notice immediately after the annual meeting of stockholders and at the same
place, or (b) as soon as practicable after the annual meeting of stockholders at
a place determined by the Board and on notice as provided in Section 2.7 of
these Bylaws.

        2.6  REGULAR AND SPECIAL MEETINGS. Except as otherwise required by law,
regular meetings of the Board may be held without notice at such times and
places as the Board determines. Special meetings of the Board may be called by
the President or by a majority of the directors then in office and shall be held
at a place and time determined by the Board and on notice as provided in Section
2.7 of these Bylaws.

        2.7  NOTICE OF MEETINGS; WAIVER OF NOTICE. Notice of the time and place
of each special meeting of the Board, and of each annual meeting not held
immediately after the annual meeting of stockholders and at the same place,
shall be mailed to each director, addressed to him at his residence or usual
place of business, at least three days before the meeting, or telegraphed to him
at such place, or delivered to him personally or by telephone, at least 48 hours
before the meeting; provided, however, that longer notice shall be given when
longer notice shall be required by law. Notice need not be given to any director
who submits a signed waiver of notice before or after the meeting, or who
attends the meeting without protesting the lack of notice to him, either before
the meeting or when it begins. Notice of any adjourned meeting need not be
given, other than by announcement at the meeting at which the adjournment is
taken.

        2.8  RESIGNATION AND REMOVAL OF DIRECTORS. Any director may resign at
any time by giving notice in writing to the President or the Clerk of the
corporation, to take effect at the time specified therein. The acceptance of
such resignation, unless required by the terms thereof, shall not be necessary
to make it effective. Any or all of the directors may be removed at any time,
either with or without cause, by vote of the holders of a majority of the issued
and outstanding stock entitled to vote or by a majority of the entire Board.

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        2.9  VACANCIES. Any vacancy in the Board, including one created by an
increase in the number of directors, may be filled for the unexpired term by a
majority vote of the remaining directors, though not a quorum.

        2.10 COMPENSATION. Directors shall receive such compensation and
reimbursement of expenses in connection with the performance of their duties as
the Board determines. A director may also be paid for serving the corporation,
its affiliates or subsidiaries in other capacities.

3. COMMITTEES.

        3.1  EXECUTIVE COMMITTEE. The Board, by resolution adopted by a majority
of the entire Board, may designate an Executive Committee, which shall have all
the authority of the Board, except as otherwise provided in such resolution or
by law, and shall serve at the pleasure of the Board. A majority of the members
of the Executive Committee shall constitute a quorum for the transaction of
business at every meeting of the Executive Committee. Vacancies in the Executive
Committee shall be filled by the Board. The Board may designate one or more
directors as alternate members of the Executive Committee, who may replace any
absent or disqualified member at any meeting of the Executive Committee. In the
absence or disqualification of any member of the Executive Committee, if no
alternate member has been designated by the Board, the member or members present
at the meeting of the Executive Committee and not disqualified, whether or not a
quorum, may, by unanimous vote, appoint another director to act at the meeting
in place of the absent or disqualified member.

        3.2  EXECUTIVE COMMITTEE MEETINGS. The Executive Committee shall adopt
rules of procedure and shall meet as provided by those rules or by resolutions
of the Board. The Executive Committee shall keep minutes of its meetings, and
all actions of the Executive Committee shall be reported to the Board at its
next meeting succeeding such action.

        3.3  OTHER COMMITTEES. The Board, by resolution adopted by a majority of
the entire Board, may designate other committees of directors, to serve at the
pleasure of the Board, with such powers and duties as the Board determines.

4. OFFICERS.

        4.1  EXECUTIVE OFFICERS. The executive officers of the corporation shall
be the President, one or more Vice Presidents (if designated by the Board), the
Clerk and the Treasurer.

        4.2  ELECTION; TERMS OF OFFICE. The executive officers of the
corporation shall be elected annually by the Board, and each such officer shall
hold office until the next annual meeting of the Board and until the election
and qualification of his successor, subject to the provisions of Section 4.4 of
these Bylaws.

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        4.3  OTHER OFFICERS. The Board or the President, subject to the control
of the Board, may appoint other officers (including Assistant Vice Presidents,
Assistant Clerks and Assistant Treasurers), agents or employees, each of whom
shall hold office for such period and have such powers and duties as the Board
or the President, subject to the control of the Board, determines. The Board may
delegate to any other executive officer or to any committee the power to appoint
and define the powers and duties of any such officers, agents or employees.

        4.4  RESIGNATION AND REMOVAL OF OFFICERS. Any officer may resign at
any time by giving written notice to the President or the Clerk of the
corporation, to take effect at the time specified therein. The acceptance of
such resignation, unless required by the terms hereof, shall not be necessary to
make it effective. Any executive officer may be removed at any time, either with
or without cause, by a majority of the entire Board. Any other officer may be
removed at any time, either with or without cause, by the Board, or by the
committee or executive officer who appointed him.

        4.5  VACANCIES. A vacancy in any office may be filled for the unexpired
term in the manner prescribed in Sections 4.2 or 4.3 of these Bylaws for
election or appointment to the office.

        4.6  THE PRESIDENT. The President shall be the chief executive officer
of the corporation and shall preside at all meetings of the Board and of the
stockholders. Subject to the control of the Board, the President shall have
general supervision over the business of the corporation and shall have such
other powers and duties as presidents of corporations usually have or as the
Board assigns to him. The President need not be a director.

        4.7  VICE PRESIDENTS. Each Vice President shall have such designation as
the Board may determine and such powers and duties as the Board or the
President, subject to the control of the Board, assigns him. In the absence of
the President, the Vice Presidents, if any, in order of their seniority (unless
otherwise designated by the Board), shall act in the President's place.

        4.8  THE CLERK. The Clerk shall be the secretary of, and keep the
minutes of, all meetings of the Board and of the stockholders, shall be
responsible for giving notice of all meetings of stockholders and of the Board,
shall keep the seal and shall affix it to any instrument when so authorized by
the Board and shall have such other powers and duties as the Board or the
President, subject to the control of the Board, assigns him. In the absence of
the Clerk from any meeting, the minutes shall be kept by the person appointed
for that purpose by the presiding officer. The Clerk shall be a resident of
Massachusetts unless the corporation has a resident agent appointed for the
service of process.

        4.9  THE TREASURER. The Treasurer shall be the chief financial officer
of the corporation, shall have charge of the corporation's books and accounts,
shall have charge of and be responsible for all funds, securities, receipts and
disbursements of the corporation and shall have

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such other powers and duties as treasurers of corporations usually have or as
the Board or the President, subject to the control of the Board, assigns him.

5. SHARES.

        5.1  CERTIFICATES. The shares of the corporation shall be represented by
certificates in the form approved by the Board.

        5.2  TRANSFER AGENTS AND REGISTRARS: SIGNATURES. The corporation may
have one or more transfer agents and one or more registrars of its shares, whose
respective duties shall be defined by the Board. The transfer agent may also be
designated as registrar. Each certificate of stock shall be signed by the
President or a Vice President and by the Treasurer or an Assistant Treasurer,
but when a certificate is countersigned by a transfer agent or a registrar
(other than a director, officer or employee of the corporation) such signatures
may be facsimiles.

        5.3  TRANSFERS. Shares shall be transferable only on the corporation's
books (which may be maintained by the transfer agent and registrar), upon
surrender of the certificate for the shares properly endorsed.

6. MISCELLANEOUS.

        6.1  SEAL. The Board shall adopt a corporate seal, which shall be in the
form of a circle and shall bear the corporation's name, the year in which it was
incorporated and the words "Corporate Seal" and "Massachusetts."

        6.2  FISCAL YEAR. The Board may determine the corporation's fiscal
year.

        6.3  VOTING OF SHARES IN OTHER CORPORATIONS. Shares in other
corporations which are held by the corporation may be represented and voted by
the President or a Vice President or by proxy or proxies appointed by one of
them. The Board may, however, appoint some other person to vote the shares.

        6.4  AMENDMENTS. Bylaws may be amended, repealed or adopted by the
stockholders or, to the extent permitted by the Articles of Organization, by a
majority of the entire Board, but any Bylaw adopted by the Board may be amended
or repealed by the stockholders. If the directors amend, repeal or adopt a
Bylaw, notice of the substance of such action shall be given to all stockholders
entitled to vote prior to or along with the notice of the next stockholders'
meeting following such action.

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