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                                                                    Exhibit 3.31

                                STATE OF VERMONT

                          OFFICE OF SECRETARY OF STATE

[GRAPHIC]

I, DEBORAH L. MARKOWITZ, SECRETARY OF STATE OF THE STATE OF VERMONT, DO HEREBY
CERTIFY THAT THE ATTACHED IS A CERTIFIED COPY OF.


                             CORPORATION DDOCUMENTS

                                      FOR
                                MAXI GREEN INC.


                                                JULY 23, 2004


                                                GIVEN UNDER MY HAND AND THE SEAL
                                                OF THE STATE OF VERMONT, AT
                                                MONTPELIER, THE STATE CAPITAL


                                                /s/ Deborah L. Markowitz

                                                DEBORAH L. MARKOWITZ
[SEAL]                                          SECRETARY OF STATE

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                            ARTICLES OF INCORPORATION

                                       OF

                                 MAXI GREEN INC.



                                STATE OF VERMONT

                           Secretary of State's Office

                               Filed May 21, 2003                  VERMONT
                                                              SECRETARY OF STATE
                                 /s/ [ILLEGIBLE]
                              ----------------------        2003 MAY 21 AM 8:39
                                SECRETARY OF STATE


                        Filing Fee of $75 has been paid

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                           ARTICLES OF INCORPORATION

                                       OF

                                MAXI GREEN INC.

                                   ARTICLE I

                                      NAME

     The name of the corporation shall be Maxi Green Inc.

                                   ARTICLE II

                     REGISTERED OFFICE AND REGISTERED AGENT

     The initial registered office of the corporation shall be One Church
Street, City of Burlington, County of Chittenden, State of Vermont 05401, and
the initial registered agent at such address shall be Paul, Frank & Collins a
Professional Corporation.

                                   ARTICLE III

                                 OPERATING YEAR

     The fiscal year end of the corporation shall be May 31, or as fixed by the
board of directors from time to time.

                                   ARTICLE IV

                               GENERAL CORPORATION

     This corporation is a Vermont general corporation, formed pursuant to Title
11A of Vermont Statutes Annotated, which is entitled the "Vermont Business
Corporation Act."

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                                    ARTICLE V

                                AUTHORIZED SHARES

     The aggregate number of shares the corporation shall have authority to
issue is ten thousand (10,000) shares of one class of shares, no par value per
share, said class consisting of voting common shares. The sole class of shares
shall have unlimited voting rights and shall be entitled to receive the net
assets of the corporation upon dissolution.

                                   ARTICLE VI

                       SHAREHOLDER ACTION WITHOUT MEETING

     Action required or permitted to be taken by the shareholders of the
corporation at a shareholders' meeting may be taken without a meeting if the
action is taken by the holders of at least a majority of all of the shares
entitled to vote on the action, and if each shareholder is given prior notice of
the action proposed to be taken. Each action must be evidenced by one or more
written consents describing the action taken, signed by the holders of at least
a majority of the shares, and filed in the corporate minute book. Prompt notice
of any action taken by less than unanimous written consent in lieu of a meeting
shall be given to all shareholders entitled to vote on such action.

                                   ARTICLE VII

             GREATER QUORUM OR VOTING REQUIREMENTS FOR SHAREHOLDERS

     The shareholders of the corporation may adopt or amend a bylaw that fixes a
greater quorum or voting requirement for shareholders (or voting groups of
shareholders) than is required by the Vermont Business Corporation Act.

                                  ARTICLE VIII

                               DIRECTOR LIABILITY

     To the extent permitted by Section 2.02(b)(4) of the Vermont Business
Corporation Act, as the same may be supplemented and amended, no director of the
corporation shall be personally liable to the corporation or its shareholders
for money damages for any action taken, or any failure to take any action,
solely as a director, based on a failure to discharge his or her own duties in
accordance with Section 8.30 of the Vermont Business Corporation Act, as the
same may be supplemented and amended.

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                                   ARTICLE IX

                           INITIAL BOARD OF DIRECTORS

     Initially the corporation shall have two directors. The following
individuals shall serve as the corporation's initial directors:

<Table>
<Caption>
NAME                      ADDRESS
- ----                      -------
                       
Michel Coutu              199 Grotto Avenue
                          Providence, RI 02906

Randy A, Wyrofsky         105 Weeks Hill Road
                          Coventry, RI 02816
</Table>

                                    ARTICLE X

                                  INCORPORATOR

     The name and address of the sole incorporator is:

<Table>
<Caption>
NAME                                      ADDRESS
- ----                                      -------
                                       
Christopher J. Leff, Esq.                 337 College Street, #12
                                          Burlington, VT 05401
</Table>

     Executed by the undersigned incorporator as of this 16th day of May, 2003.


                                          INCORPORATOR:


                                          /s/ Christopher J. Leff
                                          -----------------------------------
                                          Christopher J. Leff, Esq

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