RESTATED
 
                             CERTIFICATE OF INCORPORATION
 
                                          OF
 
                              SYNAGRO TECHNOLOGIES, INC.
 
    This Restated Certificate of Incorporation (the "Certificate") of Synagro
Technologies, Inc. (the "Corporation"), was duly adopted by the Board of
Directors of the Corporation on August 5, 1996 and the stockholders of the
Corporation on August 5, 1996, as set forth below, in accordance with Sections
228, 242 and 245 of the General Corporation Law of the State of Delaware. The
original Certificate of Incorporation was filed on May 28, 1996.
 
    The following Restated Certificate of Incorporation was adopted on August
5, 1996 by the unanimous vote of the stockholders of the Corporation.  The vote
of stockholders of the Corporation by which the foregoing Restated Certificate
of Incorporation was adopted was 100 shares in favor, and no shares opposed or
not voting, out of the Corporation's total of 100 shares issued and outstanding.
The number of shares voted for the Restated Certificate of Incorporation was
sufficient for approval.
 
    The text of the Certificate of Incorporation as amended or supplemented
heretofore is hereby restated and further amended to read in its entirety as
follows:
 
    FIRST:  The name of the corporation is Synagro Technologies, Inc.
 
    SECOND:  The address of the registered office of the Corporation in the
State of Delaware shall be at Corporation Trust Center, 1209 Orange Street, City
of Wilmington, County of New Castle, Delaware 19801. The name and address of the
Corporation's registered agent in the State of Delaware is The Corporation Trust
Company, 1209 Orange Street, City of Wilmington, County of New Castle, Delaware
19801.
 
    THIRD:  The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may now or hereafter be organized under the
General Corporation Law of the State of Delaware.
 
    FOURTH:  1.  The total number of shares of stock which the Corporation
shall have authority to issue is One Hundred Ten Million (110,000,000) shares,
consisting of One Hundred Million (100,000,000) shares of Common Stock, par
value $0.002 per share (the "Common Stock"), and Ten Million (10,000,000) shares
of Preferred Stock, par value $0.002 per share (the "Preferred Stock").
 
 
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    2.  Shares of Preferred Stock may be issued from time to time in one or
more series as may be established from time to time by resolution of the Board
of Directors of the Corporation (the "Board of Directors"), each of which series
shall consist of such number of shares and have such distinctive designation or
title as shall be fixed by resolution of the Board of Directors prior to the
issuance of any shares of such series. Each such class or series of Preferred
Stock shall have such voting powers, full or limited, or no voting powers, and
such preferences and relative, participating, optional or other special rights
and such qualifications, limitations or restrictions thereof, as shall be stated
in such resolution of the Board of Directors providing for the issuance of such
series of Preferred Stock.  The Board of Directors is further authorized to
increase or decrease (but not below the number of shares of such class or series
then outstanding) the number of shares of any series subsequent to the issuance
of shares of that series.
 
    FIFTH:  In furtherance and not in limitation of the powers conferred by
statute and subject to Article Sixth hereof, the Board of Directors is expressly
authorized to adopt, repeal, rescind, alter or amend in any respect the Bylaws
of the Corporation (the "Bylaws").
 
    SIXTH:  Notwithstanding Article Fifth hereof, the Bylaws may be adopted, 
rescinded, altered or amended in any respect by the stockholders of the 
Corporation, but only by the affirmative vote of the holders of not less than 
66 2/3% of the voting power of all outstanding shares of voting stock 
regardless of class and voting together as a single voting class; PROVIDED, 
HOWEVER, that where such action is approved by a majority of the continuing 
directors the affirmative vote of a majority of the voting power of all 
outstanding shares of voting stock, regardless of class and voting together 
as a single voting class, shall be required for approval of such action.
 
    SEVENTH:  The business and affairs of the Corporation shall be managed by
and under the direction of the Board of Directors.  Except as may otherwise be
provided pursuant to Section 2 of Article Fourth hereof in connection with
rights to elect additional directors under specified circumstances which may be
granted to the holders of any series of Preferred Stock, the exact number of
directors of the Corporation shall be determined from time to time by a Bylaw or
Amendment thereto provided that the number of directors shall not be reduced to
less than three (3), except that there need be only as many directors as there
are stockholders in the event that the outstanding shares are held of record by
fewer than three (3) stockholders.
 
         Elections of directors need not be by written ballot unless the Bylaws
of the Corporation shall so provide.
 
 
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    EIGHTH:  Each director shall serve until his successor is elected and
qualified or until his death, resignation or removal; no decrease in the
authorized number of directors shall shorten the term of any incumbent director;
and additional directors, elected pursuant to Section 2 of Article Fourth hereof
in connection with rights to elect such additional directors under specified
circumstances which may be granted to the holders of any series of Preferred
Stock, shall not be included in any class, but shall serve for such term or
terms and pursuant to such other provisions as are specified in the resolution
of the Board of Directors establishing such series.
 
    NINTH:  Except as may otherwise be provided pursuant to Section 2 of
Article Fourth hereof in connection with rights to elect additional directors
under specified circumstances which may be granted to the holders of any series
of Preferred Stock, newly created directorships resulting from any increase in
the number of directors, or any vacancies on the Board of Directors resulting
from death, resignation, removal or other causes, shall be filled solely by the
affirmative vote of a majority of the remaining directors then in office, even
though less than a quorum of the Board of Directors.  Any director elected in
accordance with the preceding sentence shall hold office for the remainder of
the full term of the class of directors in which the new directorship was
created or the vacancy occurred and until such director's successor shall have
been elected and qualified or until such director's death, resignation or
removal, whichever first occurs.
 
    TENTH:  Except for such additional directors as may be elected by the
holders of any series of Preferred Stock pursuant to the terms thereof
established by a resolution of the Board of Directors pursuant to Article Fourth
hereof, any director may be removed from office with or without cause and only
by the affirmative vote of the holders of not less than 66 2/3% of the voting
power of all outstanding shares of voting stock entitled to vote in connection
with the election of such director regardless of class and voting together as a
single voting class; PROVIDED, HOWEVER, that where such removal is approved by a
majority of the continuing directors, the affirmative vote of a majority of the
voting power of all outstanding shares of voting stock entitled to vote in
connection with the election of such director, regardless of class and voting
together as a single voting class, shall be required for approval of such
removal.
 
    ELEVENTH:  Any action required or permitted to be taken by the stockholders
of the Corporation must be effected at a duly called Annual Meeting or at a
special meeting of stockholders of the Corporation, unless such action requiring
or permitting stockholder approval is approved by a majority of the continuing
directors, in which case such action may be authorized or taken by the written
consent of the holders of outstanding shares of voting stock having not less
than the minimum voting power that would be necessary to
 
 
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<PAGE>
 
authorize or take such action at a meeting of stockholders at which all shares
entitled to vote thereon were present and voted, provided, all other
requirements of applicable law and this Certificate have been satisfied.  Except
as specifically set forth in this Article Eleventh, no action may be taken by
stockholders by written consent.
 
    TWELFTH:  Meetings of stockholders of the Corporation 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 of applicable law) 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.
 
    THIRTEENTH:  For the purposes of this Restated Certificate of
Incorporation, the following definitions shall apply:
 
    (a)  "continuing director" means:  (i) any member of the Board of Directors
         who (A) is not an interested stockholder or an affiliate or associate
         of an interested stockholder and (B) was a member of the Board of
         Directors prior to the time that an interested stockholder became an
         interested stockholder; and (ii) any person who is elected or
         nominated to succeed a continuing director, or to join the Board of
         Directors, by a majority of the continuing directors.
 
    (b)  The terms "affiliate," "associate," "control,"  "interested
         stockholder," "owner," "person" and "voting stock" shall have the
         meanings set forth in Section 203(c) of the Delaware General
         Corporation Law.
 
    FOURTEENTH:    The provisions set forth in this Article Fourteenth and in
Articles Fourth, Fifth, Sixth, Seventh, Eighth, Ninth, Tenth and Eleventh hereof
may not be repealed, rescinded, altered or amended in any respect, and no other
provision or provisions may be adopted which impair(s) in any respect the
operation or effect of any such provision, except by the affirmative vote of the
holders of not less than 66 2/3% of the voting power of all outstanding shares
of voting stock regardless of class and voting together as a single voting
class, and, where such action is proposed by an interested stockholder or by any
associate or affiliate of an interested stockholder, the affirmative vote of the
holders of a majority of the voting power of all outstanding shares of voting
stock, regardless of class and voting together as a single class, other than
shares held by the interested stockholder which proposed (or the affiliate or
associate of which proposed) such action, or any affiliate or associate of such
interested stockholder; PROVIDED, HOWEVER, that where such action is approved by
a majority of the continuing directors, the affirmative vote of a majority of
the voting power of all outstanding shares of voting stock, regardless of class
and
 
 
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<PAGE>
 
voting together as a single voting class, shall be required for approval of such
action.
 
    FIFTEENTH: The Corporation reserves the right to adopt, repeal, rescind,
alter or amend in any respect any provision contained in this Certificate in the
manner now or hereafter prescribed by applicable law, and all rights conferred
on stockholders herein are granted subject to this reservation.  Notwithstanding
the preceding sentence, the provisions set forth in Articles Fourth, Fifth,
Sixth, Seventh, Eighth, Ninth, Tenth, Eleventh and Fourteenth may not be
repealed, rescinded, altered or amended in any respect, and no other provision
or provisions may be adopted which impair(s) in any respect the operation or
effect of any such provision, unless such action is approved as specified in
Article Fourteenth hereof.
 
    SIXTEENTH:  No director of the Corporation shall be liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability (a) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (b) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (c) under Section 174 of the Delaware General Corporation Law,
or (d) for any transaction from which the director derived an improper personal
benefit.  If the Delaware General Corporation Law 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 Delaware General Corporation Law.  Any
repeal or modification of this Section by the stockholders of the Corporation
shall be prospective only and shall not adversely affect any limitation on the
personal liability of a director of the Corporation existing at the time of such
repeal or modification.
 
    SEVENTEENTH:   No contract or other transaction of the Corporation with any
other person, firm or corporation, or in which this corporation is interested,
shall be affected or invalidated by: (a) the fact that any one or more of the
directors or officers of the Corporation is interested in or is a director or
officer of such other firm or corporation; or, (b) the fact that any director or
officer of the Corporation, individually or jointly with others, may be a party
to or may be interested in any such contract or transaction, so long as the
contract or transaction is authorized, approved or ratified at a meeting of the
Board of Directors by sufficient vote thereon by directors not interested
therein, to which such fact of relationship or interest has been disclosed, or
the contract or transaction has been approved or ratified by vote or written
consent of the stockholders entitled to vote, to whom such fact of relationship
or interest has been disclosed, or so long as the contract or transaction is
fair and reasonable to the
 
 
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<PAGE>
 
Corporation.  Each person who may become a director or officer of the
Corporation is hereby relieved from any liability that might otherwise arise by
reason of his contracting with the Corporation for the benefit of himself or any
firm or corporation in which he may in any way be interested.
 
    IN WITNESS WHEREOF SYNAGRO TECHNOLOGIES, INC. has caused this Restated
Certificate of Incorporation to be executed by its President and to be attested
to by its Secretary as of the 5th day of August, 1996.
 
 
                                  SYNAGRO TECHNOLOGIES, INC.
 
 
 
 
                                  By: /s/ Don L. Thone
                                     ----------------------------
                                     Don L. Thone
                                     Chief Executive Officer
 
 
 
 
                                  By: /s/ Joan M. McKinney
                                     ----------------------------
                                     Joan M. McKinney

                                     Secretary