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Exhibit 3.18

LIMITED LIABILITY COMPANY AGREEMENT

CASELLA RTG INVESTORS CO., LLC

This Limited Liability Company Agreement (this "Agreement") of Casella RTG
Investors Co., LLC is entered into by Casella Waste Systems, Inc., a Delaware
corporation (the "Member").

The Member, by execution of this Agreement, hereby forms a limited
liability company pursuant to and in accordance with the Delaware Limited
Liability Company Act (6 DEL.C. 18-101, ET SEQ.), as amended from time to time
(the "Act"), and hereby agrees as follows:

1. NAME. The name of the limited liability company formed hereby is
Casella RTG Investors Co., LLC (the "Company").

2. CERTIFICATES. Casella Waste Systems, Inc., as an authorized person
within the meaning of the Act, shall execute, deliver and file the Certificate
of Formation with the Secretary of State of the State of Delaware. Upon the
filing of the Certificate of Formation with the Secretary of State of the State
of Delaware, its powers as an authorized person shall cease and the Member shall
thereafter be designated as an authorized person within the meaning of the Act.
The Member or an Officer shall execute, deliver and file any other certificates
(and any amendments and/or restatements thereof) necessary for the Company to
qualify to do business in a jurisdiction in which the Company may wish to
conduct business.

3. PURPOSE. The Company is formed for the object and purpose of, and the
nature of the business to be conducted and promoted by the Company is, engaging
in any lawful act or activity for which limited liability companies may be
formed under the Act and engaging in any and all activities necessary,
convenient, desirable or incidental to the foregoing.

4. POWERS. In furtherance of its purposes the Company (i) shall have and
exercise all powers necessary, convenient or incidental to accomplish its
purposes as set forth in Section 3 and (ii) shall have and exercise all of the
powers and rights conferred upon limited liability companies formed pursuant to
the Act, including, without limitation, the power to:

a. acquire by purchase, lease, contribution of property or
otherwise, own, hold, sell, convey, transfer or dispose of any real or personal
property which may be necessary, convenient or incidental to the accomplishment
of the purpose of the Company;

b. act as a trustee, executor, nominee, bailee, director, officer,
agent or in some other fiduciary capacity for any person or entity and to
exercise all of the powers, duties, rights and responsibilities associated
therewith;

c. take any and all actions necessary, convenient or appropriate as
trustee, executor, nominee, bailee, director, officer, agent or other fiduciary,
including the granting or approval of waivers, consents or amendments of rights
or powers relating thereto and the execution of appropriate documents to
evidence such waivers, consents or amendments;

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d. operate, purchase, maintain, finance, improve, own, sell, convey,
assign, mortgage, lease or demolish or otherwise dispose of any real or personal
property which may be necessary, convenient or incidental to the accomplishment
of the purposes of the Company;

e. borrow money and issue evidences of indebtedness in furtherance
of any or all of the purposes of the Company, and secure the same by mortgage,
pledge or other lien on the assets of the Company;

f. invest any funds of the Company pending distribution or payment
of the same pursuant to the provisions of this Agreement;

g. prepay in whole or in part, refinance, recast, increase, modify
or extend any indebtedness of the Company and, in connection therewith, execute
any extensions, renewals or modifications of any mortgage or security agreement
securing such indebtedness;

h. enter into, perform and carry out contracts of any kind,
including, without limitation, contracts with any person or entity affiliated
with the Member, necessary to, in connection with, convenient to, or incidental
to the accomplishment of the purposes of the Company;

i. employ or otherwise engage employees, managers, contractors,
advisors, attorneys and consultants and pay reasonable compensation for such
services;

j. enter into partnerships, limited liability companies, trusts,
associations, corporations or other ventures with other persons or entities in
furtherance of the purposes of the Company; and

k. do such other things and engage in such other activities related
to the foregoing as may be necessary, convenient or incidental to the conduct of
the business of the Company, and have and exercise all of the powers and rights
conferred upon limited liability companies formed pursuant to the Act.

5. PRINCIPAL BUSINESS OFFICE. The principal business office of the
Company shall be located at such location as may hereafter be determined by the
Member.

6. REGISTERED OFFICE. The address of the registered office of the Company
in the State of Delaware is c/o The Corporation Trust Company, 1209 Orange
Street, Wilmington, DE 19801.

7. REGISTERED AGENT. The name and address of the registered agent of the
Company for service of process on the Company in the State of Delaware is The
Corporation Trust Company, l209 Orange Street, Wilmington, DE 19801.

8. MEMBERS. The name and the mailing address of the Member is set forth
on Schedule A attached hereto.

9. LIMITED LIABILITY. Except as otherwise provided by the Act, the debts,
obligations and liabilities of the Company, whether arising in contract, tort or
otherwise, shall be solely the

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debts, obligations and liabilities of the Company, and the Member shall not be
obligated personally for any such debt, obligation or liability of the Company
solely by reason of being a member of the Company.

10. CAPITAL CONTRIBUTIONS. The Member is deemed admitted as the Member of
the Company upon its execution and delivery of this Agreement. The Member will
contribute the amount of United States Dollars to the Company as listed on
Schedule A attached hereto.

11. ADDITIONAL CONTRIBUTIONS. The Member is not required to make any
additional capital contribution to the Company. However, a Member may make
additional capital contributions to the Company with the written consent of the
Member.

12. ALLOCATION OF PROFITS AND LOSSES. The Company's profits and losses
shall be allocated to the Member.

13. DISTRIBUTIONS. Distributions shall be made to the Member at the times
and in the aggregate amounts determined by the Member. Notwithstanding any
provision to the contrary contained in this Agreement, the Company shall not
make a distribution to any Member on account of its interest in the Company if
such distribution would violate the Act or other applicable law.

14. MANAGEMENT. In accordance with Section 18-402 of the Act, management
of the Company shall be vested in the Member. The Member shall have the power to
do any and all acts necessary, convenient or incidental to or for the
furtherance of the purposes described herein, including all powers, statutory or
otherwise, possessed by members of a limited liability company under the laws of
the State of Delaware. The Member has the authority to bind the Company.

15. OFFICERS. The Member may, from time to time as it deems advisable,
appoint officers of the Company (the "Officers") and assign in writing titles
(including, without limitation, President, Vice President, Secretary, and
Treasurer) to any such person. Unless the Member decides otherwise, if the title
is one commonly used for officers of a business corporation formed under the
Delaware General Corporation Law, the assignment of such title shall constitute
the delegation to such person of the authorities and duties that are normally
associated with that office. Any delegation pursuant to this Section 15 may be
revoked at any time by the Member. The initial Officers are listed on Schedule B
attached hereto. The Member may revise Schedule B in its sole discretion at any
time.

16. OTHER BUSINESS. The Member may engage in or possess an interest in
other business ventures (unconnected with the Company) of every kind and
description, independently or with others. The Company shall not have any rights
in or to such independent ventures or the income or profits therefrom by virtue
of this Agreement.

17. EXCULPATION AND INDEMNIFICATION. No Member or Officer shall be liable
to the Company, or any other person or entity who has an interest in the
Company, for any loss, damage or claim incurred by reason of any act or omission
performed or omitted by such Member or Officer in good faith on behalf of the
Company and in a manner reasonably believed to be within the scope of the
authority conferred on such Member or Officer by this Agreement,

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except that a Member or Officer shall be liable for any such loss, damage or
claim incurred by reason of such Member's or Officer's willful misconduct. To
the fullest extent permitted by applicable law, a Member or Officer shall be
entitled to indemnification from the Company for any loss, damage or claim
incurred by such Member or Officer by reason of any act or omission performed or
omitted by such Member or Officer in good faith on behalf of the Company and in
a manner reasonably believed to be within the scope of the authority conferred
on such Member or Officer by this Agreement, except that no Member or Officer
shall be entitled to be indemnified in respect of any loss, damage or claim
incurred by such Member or Officer by reason of willful misconduct with respect
to such acts or omissions; PROVIDED, HOWEVER, that any indemnity under this
Section 17 shall be provided out of and to the extent of Company assets only,
and no Member shall have personal liability on account thereof.

18. ASSIGNMENTS.

a. A Member's entire interest in the Company (the "Membership
Interest") is transferable either voluntarily or by operation of law. The Member
may sell, assign, convey, exchange, mortgage, pledge, grant, hypothecate or
transfer all or a portion of such Member's Membership Interest. In the event of
the transfer of less than all of such Member's Membership Interest, the
transferee shall become a member of the Company on such terms and condition as
such member, the applicable Member and the Company shall agree upon. In the
event of the transfer of the Member's entire Membership Interest, the transferee
shall succeed to all the Member's rights under this Agreement. Upon the transfer
of the Member's Membership Interest, the transferee shall become a member of the
Company upon the completion of the transfer without further action.

b. Without limiting any of the forgoing, upon the sale, transfer or
other disposition of any Member's entire Membership Interest pursuant to any
pledge thereof to any lender (or any agent, trustee or other representative for
any lender or group of lenders), the transferee of such Membership Interest
shall become a member of the Company and shall acquire all right, title and
interest of the Member in the Company, including all rights under this
Agreement, and the Member shall be withdrawn as a member of the Company
hereunder and shall have no further right, title or interest in the Company or
under this Agreement.

19. RESIGNATION. A Member may resign from the Company with the written
consent of the Member. If a Member is permitted to resign pursuant to this
Section, an additional member shall be admitted to the Company, subject to
Section 20, upon its execution of an instrument signifying its agreement to be
bound by the terms and conditions of this Agreement. Such admission shall be
deemed effective immediately prior to the resignation, and, immediately
following such admission, the resigning Member shall cease to be a member of the
Company.

20. ADMISSION OF ADDITIONAL MEMBERS. One (1) or more additional members of
the Company may be admitted to the Company with the written consent of the
Member.

21. DISSOLUTION.

a. The Company shall dissolve, and its affairs shall be wound up
upon the first to occur of the following: (i) the written consent of the Member,
(ii) at any time there are no

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Members of the Company, unless the business of the Company is continued in a
manner permitted by the Act, or (iii) the entry of a decree of judicial
dissolution under Section 18-802 of the Act.

b. The bankruptcy of the Member will not cause the Member to cease
to be a member of the Company and upon the occurrence of such an event, the
business of the Company shall continue without dissolution.

c. In the event of dissolution, the Company shall conduct only such
activities as are necessary to wind up its affairs (including the sale of the
assets of the Company in an orderly manner), and the assets of the Company shall
be applied in the manner, and in the order of priority, set forth in Section
18-804 of the Act.

22. SEPARABILITY OF PROVISIONS. Each provision of this Agreement shall be
considered separable and if for any reason any provision or provisions herein
are determined to be invalid, unenforceable or illegal under any existing or
future law, such invalidity, unenforceability or illegality shall not impair the
operation of or affect those portions of this Agreement which are valid,
enforceable and legal.

23. COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original of this Agreement.

24. ENTIRE AGREEMENT. This Agreement constitutes the entire agreement of
the Member with respect to the subject matter hereof.

25. GOVERNING LAW. This Agreement shall be governed by, and construed
under, the laws of the State of Delaware (without regard to conflict of laws
principles), all rights and remedies being governed by said laws.

26. AMENDMENTS. This Agreement may not be modified, altered, supplemented
or amended except pursuant to a written agreement executed and delivered by the
Member.

IN WITNESS WHEREOF, the undersigned, intending to be legally bound hereby,
has duly executed this Agreement as of the 31st day of August, 2001.

Casella Waste Systems, Inc.

By: /s/ Richard A. Norris
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Richard A. Norris
Title: Chief Financial Officer/Treasurer

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Schedule A

to Casella RTG Investors Co., LLC Limited Liability Company Agreement

MEMBER

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Agreed Value of Percentage
Name Mailing Address Capital Contribution Interest
---- ------------------- -------------------- --------

Casella Waste Systems, Inc. 25 Greens Hill Lane 100%
Rutland, VT 05701
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A-1
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Schedule B

to Casella RTG Investors Co., LLC Limited Liability Company Agreement

Name Title
---- -----

John w. Casella President / Secretary

Douglas R. Casella Vice President

James W. Bohlig Vice President

Richard A. Norris Vice President / Treasurer

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