<PAGE>
                                                                    EXHIBIT 10.5

                                 FIRST AMENDMENT

         THIS FIRST AMENDMENT dated as of February 25, 2002 (this "Amendment")
amends the Second Amended and Restated Credit Agreement dated as of August 14,
2000 (the "Credit Agreement") among Synagro Technologies, Inc. (the "Company"),
various financial institutions (the "Banks") and Bank of America, N.A., as
administrative agent (in such capacity, the "Administrative Agent"). Terms
defined in the Credit Agreement are, unless otherwise defined herein or the
context otherwise requires, used herein as defined therein.

         WHEREAS, the Company, the Banks and the Administrative Agent have
entered into the Credit Agreement; and

         WHEREAS, the parties hereto desire to amend the Credit Agreement to (a)
add the parties listed on the signatures hereof under the heading "New Banks"
(collectively the "New Banks") as "Banks" thereunder and (b) make certain other
changes as more fully set forth herein;

         NOW, THEREFORE, the parties hereto agree as follows:

         SECTION 1 Amendments. Subject to the satisfaction of the conditions
precedent set forth in Section 3, the Credit Agreement shall be amended as
follows:

         1.1 Addition of Definitions. The following new definitions are added to
Section 1.1 of the Credit Agreement in proper alphabetical sequence:

                  "Non-Recourse Debt means the Rhode Island Non-Recourse Debt
         and the SPV Non-Recourse Debt.

                  Sale-Leaseback Transaction means the sale by the Company
         and/or one or more Subsidiaries of railcars, containers or other mobile
         equipment and the concurrent lease, as lessee, of such equipment by the
         Company and/or one or more Subsidiaries pursuant to a lease which (a)
         is treated as an operating lease for financial reporting purposes (as
         determined pursuant to Statement of Financial Accounting Standards No.
         13), (b) has a term (or which is renewable or extendible solely at the
         option of the lessee for a total period) of not less than five years,
         (c) has covenants and defaults no more restrictive than this Agreement,
         has amortization reasonably satisfactory to the Administrative Agent
         and (d) has an imputed interest rate (absent default) not exceeding
         LIBOR (as quoted on Telerate Page 3750 or any similar service) plus 5%.

                  SPV means a Subsidiary of the Company whose organizational
         documents limit the activities of such Subsidiary to the development,
         operation or purchase of SPV Assets and activities related thereto.


<PAGE>


                  SPV Asset means, with respect to any SPV, any facility or
         other asset developed, owned or purchased by such SPV in compliance
         with the terms of its organizational documents.

                  SPV Non-Recourse Debt means, with respect to any SPV, Debt
         incurred by such SPV for the purpose of financing the development,
         operation or purchase of SPV Assets which is non-recourse to the
         Company and its other Subsidiaries (except for customary warranties and
         performance guaranties (so long as such guaranties are not guaranties
         of payment obligations of such SPV) given in connection with
         non-recourse Debt) and which, in any event, has terms reasonably
         acceptable to the Administrative Agent.

         1.2 Amendments to Definitions.

         (a) The definition of "Applicable Asset Sale Proceeds" is amended by
(i) deleting the word "and" at the end of clause (i) and substituting a
semicolon therefor, (ii) redesignating the existing clause (ii) as clause "(iv)"
and (iii) inserting the following new clauses (ii) and (iii):

         "(ii) 50% of the Net Cash Proceeds from the Sale-Leaseback Transaction;
         (iii) 100% of the Net Cash Proceeds from any sale of receivables
         permitted by Section 10.11(f); and".

         (b) The definition of "EBITDA" is amended by (i) deleting the reference
to "Interest Expense" therein and substituting "interest expense" therefor and
(ii) deleting the words "the Rhode Island" before the words "Non-Recourse Debt"
therein.

         (c) The definitions of "Fixed Charge Coverage Ratio" and "Funded Debt"
are amended by deleting the words "the Rhode Island" before the words
"Non-Recourse Debt" therein.

         (d) The definition of "Interest Expense" is amended in its entirety to
read as follows:

                  "Interest Expense means, as to any Person for any period, the
         consolidated interest expense of such Person and its Subsidiaries for
         such period (including all imputed interest on Capital Leases),
         excluding, in the case of the Company, any portion thereof attributable
         to the Baltimore Bonds and the Non-Recourse Debt."

         (e) The definition of "Revolving Commitment Amount" is amended in its
entirety to read as follows:

                  "Revolving Commitment Amount means $50,000,000, as such amount
         may be changed from time to time pursuant to Section 6.2."

         1.3 Amendment to Section 2.1.2. The proviso to Section 2.1.2 is amended
in its entirety to read as follows:


                                      -2-
<PAGE>


                  "; provided that (i) the aggregate Stated Amount of all
         Letters of Credit shall not at any time exceed $50,000,000 and (ii) the
         Revolving Outstandings shall not at any time exceed the Revolving
         Commitment Amount".

         1.4 Amendments to Section 6.

         (a) The caption of Section 6 is amended in its entirety to read
"REPAYMENT OF LOANS; CHANGE IN OR TERMINATION OF THE COMMITMENTS; PREPAYMENTS".

         (b) The caption of Section 6.2 is amended in its entirety to read
"Changes in the Commitments".

         (c) A new Section 6.2.6 is added to read as follows:

                  "6.2.6 Optional Increase in Revolving Commitments. The Company
         may, from time to time, by means of a letter delivered to the
         Administrative Agent substantially in the form of Exhibit I, request
         that the Revolving Commitment Amount be increased to up to $60,000,000
         by (a) increasing the Revolving Commitment of one or more Banks which
         have agreed to such increase and/or (b) adding one or more commercial
         banks or other Persons as a party hereto (each an "Additional Bank")
         with a Revolving Commitment in an amount agreed to by any such
         Additional Bank; provided that no Additional Bank shall be added as a
         party hereto without the written consent of the Administrative Agent
         (which shall not be unreasonably withheld) or if an Event of Default or
         an Unmatured Event of Default exists. Any increase in the Revolving
         Commitment Amount pursuant to this Section 6.2.6 shall be effective
         three Business Days after the date on which the Administrative Agent
         has received and accepted the applicable increase letter in the form of
         Annex 1 to Exhibit I (in the case of an increase in the Revolving
         Commitment of an existing Bank) or assumption letter in the form of
         Annex 2 to Exhibit I (in the case of the addition of a commercial bank
         or other Person as a new Bank). The Administrative Agent shall promptly
         notify the Company and the Banks of any increase in the amount of the
         Revolving Commitment Amount pursuant to this Section 6.2.6 and of the
         Revolving Commitment and Revolving Percentage of each Bank after giving
         effect thereto. The Company acknowledges that, in order to maintain
         Loans in accordance with each Bank's Revolving Percentage, a
         reallocation of the Revolving Commitments as a result of a non-pro-rata
         increase in the Revolving Commitment Amount may require prepayment of
         all or portions of certain Loans on the date of such increase (and any
         such prepayment shall be subject to the provisions of Section 8.4)."

         1.5 Amendment to Section 10.6.5. The table contained in Section 10.6.5
is amended in its entirety to read as follows:


<Table>
<Caption>
                                                        Debt to Capitalization
                  "Period                                     Percentage
                  -------                               ----------------------
<S>                                                     <C>
                  1/01/02 through 6/30/02                     62.5%
                  7/01/02 and thereafter                      60.0%."
</Table>



                                      -3-
<PAGE>



         1.6 Amendments to Section 10.6.6. Section 10.6.6 is amended by amending
clause (y) in contained in the first parenthetical phrase therein in its
entirety to read as follows: "(y) Capital Expenditures relating to the Rhode
Island Facility and the SPV Assets to the extent financed with Non-Recourse
Debt".

         1.7 Amendments to Section 10.7. Section 10.7 is amended by (a) deleting
the word "and" at the end of clause (i); (b) deleting the period at the end of
clause (j) and substituting a semi-colon followed by the word "and" therefor;
and (c) inserting the following new clause (k) in proper sequence:

                  "(k) SPV Non-Recourse Debt used to finance the purchase or
         construction of SPV Assets after February 25, 2002 for use in
         businesses of the types described in Section 10.19; provided that the
         aggregate principal amount of all such Debt shall not at any time
         exceed $50,000,000."

         1.8 Amendments to Section 10.8. Section 10.8 is amended by (a)
inserting the phrase "(other than deposits permitted under Section
10.20(f)(ii))" following the phrase "deposits or advances for borrowed money" in
clause (b); (b) deleting the word "and" at the end of clause (f); (c) deleting
the period at the end of clause (g) and substituting a semi-colon therefor; and
(d) inserting the following new clauses (h), (i) and (j) in proper sequence:

                  "(h) Liens arising in connection with accounts receivable
         factoring arrangements permitted under Section 10.11;

                  (i) Liens arising in connection with the Sale-Leaseback
         Transaction attaching only to the property being leased; and

                  (j) Liens on SPV Assets arising in connection with SPV
         Non-Recourse Debt permitted by Section 10.7(k)."

         1.9 Amendment to Section 10.9. Section 10.9 is amended in its entirety
to read as follows:

                  "10.9 Operating Leases. Not permit (a) the aggregate amount of
         proceeds received from the Sale-Leaseback Transaction to exceed
         $20,000,000; (b) the aggregate amount of all rental payments made (or
         scheduled to be made) under all Operating Leases (excluding (i) the
         operating lease arising in connection with the Sale-Leaseback
         Transaction, (ii) any lease of equipment for a period of less than six
         months which is not renewable or extendible solely at the option of the
         lessee thereunder, (iii) Operating Leases entered into after February
         25, 2002 which (x) are for equipment to be used in


                                      -4-
<PAGE>


         servicing contracts entered into after such date, (y) have a term (or
         are renewable or extendible solely at the option of the lessee for a
         period) of not less than five years and (z) are approved in writing by
         the Administrative Agent; provided that the aggregate amount of all
         rental payments made (or scheduled to be made) pursuant to this clause
         (iii) shall not exceed $4,000,000 during any Fiscal Year, and (iv) the
         Operating Leases listed on Schedule 10.9) by the Company and its
         Subsidiaries (on a consolidated basis) in any Fiscal Year to exceed
         1.0% of Net Worth as of the end of the prior Fiscal Year."

         1.10 Amendment to Section 10.10. The proviso contained in Section 10.10
is amended in its entirety to read as follows:

         "provided that (i) any Subsidiary may declare and pay dividends to the
         Company or to any other wholly-owned Subsidiary; (ii) the Company may
         make regularly scheduled payments of interest on any Subordinated Debt
         if the holder of the Subordinated Debt is permitted to receive such
         payments at such time under the Subordination Agreement; (iii) the
         Company may make cash repurchases of its capital stock held by
         employees (or former employees) and cash payments on Subordinated Debt
         permitted under Section 10.7(i) in an aggregate amount, for all such
         repurchases and payments, not in excess of $250,000 in any fiscal year;
         (iv) the Company may make repurchases of its capital stock held by
         employees (or former employees) with the proceeds of the substantially
         concurrent issuance of stock to employees (or former employees) or to
         GTCR Capital or GTCR Fund VII or any Affiliate of the foregoing or any
         TCW/Crescent Lender; (v) the Company may pay to GTCR Golder Rauner,
         L.L.C and its Affiliates and the TCW/Crescent Lenders fees as provided
         for in the Monitoring Agreement and the Professional Services Agreement
         as in effect on the Effective Date; and (vi) so long as the Total
         Leverage Ratio on a pro forma basis at the time of the relevant payment
         (and after giving effect thereto) is less than 2.50 to 1.0 and no Event
         of Default or Unmatured Event of Default exists or would result
         therefrom, the Company may declare and pay dividends on its preferred
         stock, make cash repurchases of its capital stock and make cash
         payments on Subordinated Debt in an aggregate amount in any Fiscal
         Year, for all such dividends, repurchases and payments described in
         this clause (vi) (in addition to any payments permitted by clauses (i)
         through (v) above), not exceeding $10,000,000 (or, if the Total
         Leverage Ratio on a pro forma basis at the time of the relevant payment
         (and after giving effect thereto) is less than 2.00 to 1.0,
         $20,000,000)."

         1.11 Amendments to Section 10.11. Section 10.11 is amended as follows:

         (a) Clause (d) is amended by (i) deleting the reference to
"$25,000,000" therein and substituting "$35,000,000" therefor and (ii) deleting
the reference to "$10,000,000" therein and substituting "$15,000,000 therefor.

         (b) Clause (e) is redesignated as clause "(g)".


                                      -5-
<PAGE>


         (c) The word "other" is inserted at the beginning of new clause (g).

         (d) The following new clauses (e) and (f) are added in proper
alphabetical sequence:

         "(e) any sale of assets pursuant to the Sale-Leaseback Transaction so
         long as such sale is consummated on or prior to June 30, 2002, (f)
         sales of receivables pursuant to factoring arrangements entered into by
         the Company or any Subsidiary in the ordinary course of business so
         long as the aggregate amount of receivables subject to such factoring
         arrangements does not exceed $3,000,000 at any time and".

         1.12 Amendment to Section 10.13. The last sentence of Section 10.13 is
amended in its entirety to read as follows:

         "Notwithstanding the foregoing, (i) so long as the Rhode Island
         Non-Recourse Debt is outstanding, neither the Company nor any
         Subsidiary shall be obligated to grant any Lien on the Rhode Island
         Facility, (ii) so long as any SPV Non-Recourse Debt is outstanding,
         neither the Company nor any Subsidiary shall be obligated to grant any
         Lien on any SPV Asset of the applicable SPV and (iii) so long as the
         Company or any Subsidiary continues to lease assets pursuant to the
         Sale-Leaseback Transaction, neither the Company nor any Subsidiary
         shall be obligated to grant any Lien on such leased assets."

         1.13 Amendment to Section 10.18. The parenthetical phrase contained in
clause (b) of Section 10.18 is amended by (a) deleting the word "and" at the end
of clause (ii) and substituting a comma therefor and (b) inserting the following
at the end of clause (iii):

         "(iv) any provision in the documentation for any SPV Non-Recourse Debt
         which prohibits a second Lien on the related SPV Assets), and

         (v) any provision in the documentation for the Sale-Leaseback
         Transaction which prohibits a second Lien on the assets leased by the
         Company or any Subsidiary pursuant to such transaction".

         1.14 Amendments to Section 10.20. Section 10.20 is amended as follows:

         (a) Clause (f) is amended in its entirety to read as follows:

         "(f) good faith deposits (i) made in connection with prospective
         acquisitions of stock or assets permitted by Section 10.11 or (ii) to
         secure payment under surety bonds permitted by Section 10.7; provided
         that the aggregate amount of all outstanding deposits made pursuant to
         clause (ii) shall not at any time exceed $5,000,000".

         (b) The word "and" at the end of clause (i) is deleted.


                                      -6-
<PAGE>


         (c) The word "and" is added at the end of clause (j).

         (d) A new clause (k) is added in proper alphabetical sequence to read
         as follows:

                  "(k) other Investments in an aggregate amount not exceeding
         $3,000,000 at any time outstanding (without giving effect to any
         write-off or write-down of any Investment)".

         (e) The proviso to Section 10.20 is amended by (i) deleting the
reference to "(f) or (g)" therein and substituting "(f), (g) or (k)" therefor
and (ii) adding the following at the end thereof immediately before the period:

         "; and provided, further, that the aggregate amount of Investments by
         the Company or any Subsidiary in SPVs shall not exceed at any time the
         sum of (x) $1,000,000 and (y) the excess of the dollar amount set forth
         in clause (k) over the aggregate amount of Investments outstanding
         pursuant to clause (k) at such time".

         1.15 Amendment to Schedule 2.1. Schedule 2.1 is amended in its entirety
to read as set forth on Schedule 2.1.

         1.16 Addition of Exhibit I. Exhibit I hereto is added to the Credit
Agreement as Exhibit I thereto.

         SECTION 2 Representations and Warranties. The Company represents and
warrants to the Administrative Agent and the Banks that, after giving effect to
the effectiveness hereof, (a) each warranty set forth in Section 9 of the Credit
Agreement (other than Section 9.6 and 9.8) is true and correct as of the date of
the execution and delivery of this Amendment by the Company, with the same
effect as if made on such date, and (b) no Event of Default or Unmatured Event
of Default exists.

         SECTION 3 Effectiveness. The amendments set forth in Section 1 above
shall become effective on the date (the "Amendment Effective Date") when the
Administrative Agent shall have received (i) counterparts of this Amendment
executed by the Company and, without duplication, each New Bank, each Bank which
will have a Revolving Commitment after giving effect to the amendments herein
greater than its Revolving Commitment before giving effect to the amendments
herein and the Required Banks, (ii) a Confirmation, substantially in the form of
Exhibit A, signed by the Company and each Subsidiary, (iii) new Notes payable to
each of the New Banks, (iv) an opinion of counsel to the Company and its
Subsidiaries in form and substance reasonably acceptable to the Administrative
Agent and (v) an amendment fee for each Bank which, on or before February 21,
2002, executes and delivers to the Administrative Agent a counterpart hereof
agreeing to the amendments set forth in Section 1, such fee to be in an amount
equal to 0.075% of the sum of such Bank's Revolving Commitment, Acquisition
Loans, Term A Loan and Term B Loan after giving effect to the amendments herein.


                                      -7-
<PAGE>


         SECTION 4 Miscellaneous.

         4.1 Continuing Effectiveness, etc. As herein amended, the Credit
Agreement shall remain in full force and effect and is hereby ratified and
confirmed in all respects. After the effectiveness of this Amendment, all
references in the Credit Agreement and the other Loan Documents to "Credit
Agreement" or similar terms shall refer to the Credit Agreement as amended
hereby.

         4.2 Counterparts. This Amendment may be executed in any number of
counterparts and by the different parties on separate counterparts, and each
such counterpart shall be deemed to be an original but all such counterparts
shall together constitute one and the same Amendment.

         4.3 Governing Law. This Amendment shall be a contract made under and
governed by the laws of the State of New York applicable to contracts made and
to be performed entirely within such state.

         4.4 Successors and Assigns. This Amendment shall be binding upon the
Company, the Banks and the Administrative Agent and their respective successors
and assigns, and shall inure to the benefit of the Company, the Banks and the
Administrative Agent and the respective successors and assigns of the Banks and
the Administrative Agent.

         4.5 New Banks. On the Amendment Effective Date, each New Bank shall
become a "Bank" under and for all purposes of the Credit Agreement, as amended
by this Agreement (as so amended, the "Amended Agreement"), shall be bound by
the Amended Agreement, and shall be entitled to the benefits of the Amended
Agreement and each other Loan Document, and each Bank shall have the applicable
Percentages set forth opposite such Bank's name on Schedule 2.1. To facilitate
the foregoing, (a) each New Bank agrees that on the Amendment Effective Date, it
will remit to the Administrative Agent funds in an amount equal the sum of its
Revolving Percentage of all outstanding Revolving Loans and the Administrative
Agent agrees to immediately (i) remit a portion of such funds to the existing
Revolving Banks, in such amounts, if any, as are necessary to reduce the
Revolving Loans of such Revolving Banks to the proper amounts after giving
effect hereto and (ii) remit the balance of such funds (if any) to the Company
and (b) the Company agrees to pay all costs required to be paid pursuant to
Section 8.4 of the Credit Agreement in connection with the foregoing. Each New
Bank agrees that all interest and fees accrued under the Credit Agreement prior
to the Amendment Effective Date are the property of the existing Banks.


                                      -8-
<PAGE>


         Delivered as of the day and year first above written.

                                       SYNAGRO TECHNOLOGIES, INC.


                                       By  /s/ J. PAUL WITHROW
                                         ---------------------------------------
                                       Title   Executive Vice President
                                            ------------------------------------



                                      S-1
<PAGE>



                                       BANK OF AMERICA, N.A., as Administrative
                                       Agent


                                       By  /s/ LILIANA CLAAR
                                         ---------------------------------------
                                       Title   Vice President
                                            ------------------------------------


                                       BANK OF AMERICA, N.A., as a Bank


                                       By  /s/ W. THOMAS BARNETT
                                         ---------------------------------------
                                       Title   Managing Director
                                            ------------------------------------



                                      S-2
<PAGE>



                                       SUNTRUST BANK, as Documentation Agent and
                                       a Bank


                                       By
                                         ---------------------------------------
                                       Title
                                            ------------------------------------



                                      S-3
<PAGE>



                                       KEY CORPORATE CAPITAL INC., as
                                       Documentation Agent and a Bank


                                       By  /s/ MICHAEL F. McCULLOUGH
                                         ---------------------------------------
                                       Title   Vice President
                                            ------------------------------------



                                      S-4
<PAGE>



                                       FLEET CAPITAL CORPORATION, as Co-Agent
                                       and a Bank

                                       By
                                         ---------------------------------------
                                       Title
                                            ------------------------------------



                                      S-5
<PAGE>



                                       IBJ WHITEHALL BANK & TRUST COMPANY


                                       By
                                         ---------------------------------------
                                       Title
                                            ------------------------------------



                                      S-6
<PAGE>



                                       ARK II CLO 2001-1, LIMITED

                                       By: Patriarch Partners II, LLC,
                                       its Collateral Manager

                                       By:  /s/ DENNIS DOLAN
                                         ---------------------------------------
                                       Name:    Dennis Dolan
                                            ------------------------------------
                                       Title:   Manager



                                      S-7
<PAGE>



                                       U.S. BANK NATIONAL ASSOCIATION

                                       By /s/ CHRISTOPHER W. RUPP
                                         ---------------------------------------
                                       Title  Assistant Vice President
                                            ------------------------------------



                                      S-8
<PAGE>


                                       THE BANK OF NOVA SCOTIA


                                       By /s/ AMANDA NOTSWORTHY
                                         ---------------------------------------
                                       Title  Sr. Team Leader
                                            ------------------------------------



                                      S-9
<PAGE>



                                       COBANK, ACB


                                       By /s/ TODD B. HATTENBACH
                                         ---------------------------------------
                                       Title  Assistant Vice President
                                            ------------------------------------



                                      S-10
<PAGE>



                                       HELLER FINANCIAL INC.


                                       By /s/ ROBERT M. REEG
                                         ---------------------------------------
                                       Title  Assistant Vice President
                                            ------------------------------------




                                      S-11
<PAGE>



                                       LIBERTY-STEIN ROE ADVISOR FLOATING
                                       RATE ADVANTAGE FUND
                                       By: Stein Roe & Farnham Incorporated, as
                                       Advisor


                                       By /s/ JAMES R. FELLOWS
                                         ---------------------------------------
                                       Title  Senior Vice President
                                            ------------------------------------

                                       STEIN ROE FLOATING RATE LIMITED
                                       LIABILITY COMPANY


                                       By
                                       By /s/ JAMES R. FELLOWS
                                         ---------------------------------------
                                       Title  Senior Vice President
                                            ------------------------------------

                                       STEIN ROE & FARNHAM CLO I LTD.
                                       By: Stein Roe & Farnham Incorporated, as
                                       Portfolio Manager


                                       By /s/ JAMES R. FELLOWS
                                         ---------------------------------------
                                       Title  Senior Vice President
                                            ------------------------------------

                                       KEYPORT LIFE INSURANCE COMPANY
                                       By: Stein Roe & Farnham Incorporated, as
                                       Agent for Keyport Life Insurance Company


                                       By /s/ JAMES R. FELLOWS
                                         ---------------------------------------
                                       Title  Senior Vice President
                                            ------------------------------------

                                       SRF 2000 LLC


                                       By /s/ ANN E. MORRIS
                                         ---------------------------------------
                                       Title  Assistant Vice President
                                            ------------------------------------


                                       SRF TRADING, INC.


                                       By /s/ ANN E. MORRIS
                                         ---------------------------------------
                                       Title  Assistant Vice President
                                            ------------------------------------


                                      S-12
<PAGE>


                                       DENALI CAPITAL CLO I, LTD.


                                       By
                                         ---------------------------------------
                                       Title
                                            ------------------------------------


                                      S-13
<PAGE>


                                       NEW BANKS:


                                       J.H. WHITNEY MARKET VALUE FUND L.P.


                                       By /s/ MARC S. DIAGONALE
                                         ---------------------------------------
                                       Title  Authorized Signatory
                                            ------------------------------------




                                      S-14
<PAGE>



                                       LASALLE BANK NATIONAL ASSOCIATION


                                       By
                                         ---------------------------------------
                                       Title
                                            ------------------------------------



                                      S-15
<PAGE>



                                       CAPITAL FARM CREDIT


                                       By /s/ BEN R. NOVOSAD
                                         ---------------------------------------
                                       Title  CEO
                                            ------------------------------------



                                      S-16
<PAGE>



                                  CONFIRMATION

                          Dated as of February 25, 2002

To: Bank of America, N.A., individually and as Administrative Agent, and the
    other financial institutions party to the Credit Agreement referred to below

         Please refer to (a) the Second Amended and Restated Credit Agreement
dated as of August 14, 2000 (as amended, the "Credit Agreement") among Synagro
Technologies, Inc., various financial institutions (the "Banks") and Bank of
America, N.A., as administrative agent (the "Administrative Agent"); (b) the
other Loan Documents (as defined in the Credit Agreement), including the
Guaranty and the Restated Security Agreement; and (c) the First Amendment dated
as of February 25, 2002 to the Credit Agreement (the "First Amendment").

         Each of the undersigned hereby confirms to the Administrative Agent and
the Banks that, after giving effect to the First Amendment and the transactions
contemplated thereby, each Loan Document to which such undersigned is a party
continues in full force and effect and is the legal, valid and binding
obligation of such undersigned, enforceable against such undersigned in
accordance with its terms.

                         SYNAGRO TECHNOLOGIES, INC.


                         By: /s/ J. PAUL WITHROW
                            ----------------------------
                         Name Printed: J. Paul Withrow
                                      ------------------
                         Title: Executive Vice President
                               -------------------------

                         SYNAGRO WEST, INC.
                         SYNAGRO OF CALIFORNIA, INC. (formerly known as Pima
                         Gro Systems, Inc.)
                         SYNAGRO COMPOSTING COMPANY OF
                         CALIFORNIA, INC. (formerly known as Recyc, Inc.)
                         SYNAGRO MIDWEST, INC.
                         SYNAGRO OF MICHIGAN, INC. (formerly known as National
                         Resource Recovery, Inc.)
                         SYNAGRO OF WISCONSIN, INC. (formerly known as A&J
                         Cartage, Inc.)
                         SYNAGRO SOUTHWEST, INC.
                         SYNAGRO OF TEXAS - VITAL-CYCLE, INC.
                         SYNAGRO OF TEXAS - CDR, INC. (formerly known as
                         Synagro of Texas, Inc. and CDR Environmental, Inc.)



                                      A-1
<PAGE>



                         SYNAGRO SOUTHEAST, INC.
                         SYNAGRO OF NORTH CAROLINA - AMSCO, INC.
                         SYNAGRO OF FLORIDA - ANTI-POLLUTION, INC.
                         SYNAGRO OF NORTH CAROLINA - EWR, INC. (formerly
                         known as Synagro of North Carolina and Environmental
                         Waste Recycling, Inc.)
                         SYNAGRO OF FLORIDA - A&J, INC. (formerly known as A&J
                         Cartage Southwest, Inc.)
                         SYNAGRO NORTHEAST, INC.
                         SYNAGRO MID-ATLANTIC, INC. (formerly known as CDR
                         Mid-Atlantic, a division of CDR Environmental, Inc.)
                         ORGANI-GRO, INC.
                         ST INTERCO, INC.
                         COMPOSTING CORPORATION OF AMERICA
                         NEW HAVEN RESIDUALS SYSTEMS, INC.
                         RESIDUAL TECHNOLOGIES SYSTEMS, INC.
                         FAIRHAVEN RESIDUAL SYSTEMS, INC.
                         NEW ENGLAND TREATMENT COMPANY, INC.
                         NETCO-CONNECTICUT, INC.
                         NETCO-WATERBURY, INC.
                         NETCO-RESIDUALS MANAGEMENT SYSTEMS, INC.
                         SYNAGRO OF FLORIDA - DAVIS WATER, INC.
                         SYNAGRO OF FLORIDA - ECOSYSTEMS, INC.
                         SYNAGRO OF MINNESOTA - REHBEIN INC.
                         PROVIDENCE SOILS, LLC
                         SYNAGRO - BALTIMORE, L.L.C.
                         SYNAGRO TEXAS, INC.
                         SYNAGRO DELAWARE, INC.
                         SYNAGRO - WWT, INC.
                         RESIDUALS PROCESSING, INC.
                         FUTURE-TECH ENVIRONMENTAL SERVICES, INC.
                         SYNAGRO MIDWEST - ENVIROLAND, INC.
                         NYOFCO HOLDINGS INC.
                         SYNAGRO - WCWNJ, INC.
                         SOARING VISTA PROPERTIES, INC.
                         ENVIRONMENTAL PROTECTION & IMPROVEMENT
                         COMPANY, INC.
                         ATLANTA RESIDUALS COMPANY, LLC
                         SYNAGRO DIGESTION, INC.


                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------



                                      A-2
<PAGE>



                         NEW YORK ORGANIC FERTILIZER COMPANY
                         By: Synagro - WWT, Inc., its Partner


                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------


                         NETCO-RESIDUALS MANAGEMENT, LIMITED
                         PARTNERSHIP

                         By:    Netco-Residuals Management Systems, Inc.,
                                its General Partner

                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------


                         RESIDUAL TECHNOLOGIES, LIMITED PARTNERSHIP

                         By:    Residual Technologies Systems, Inc.,
                                its General Partner


                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------


                         FAIRHAVEN RESIDUALS, LIMITED PARTNERSHIP

                         By:    Fairhaven Residual Systems, Inc.,
                                its General Partner


                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------



                                      A-3
<PAGE>




                         NETCO-WATERBURY, LIMITED PARTNERSHIP

                         By:    Netco-Waterbury, Inc., its General Partner


                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------


                         NEW HAVEN RESIDUALS, LIMITED PARTNERSHIP

                         By:    New Haven Residuals Systems, Inc.,
                                its General Partner


                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------


                         SYNAGRO MANAGEMENT, L.P.


                         By:    Synagro Texas, Inc.,
                                its General Partner


                         By: /s/ J. PAUL WITHROW
                            --------------------------------------------
                         Name Printed: J. Paul Withrow
                                      ----------------------------------
                         Title: Executive Vice President
                               -----------------------------------------



                                      A-4
<PAGE>



                                    EXHIBIT I

                                     FORM OF
                                INCREASE REQUEST

                          ______________________, 20___

Bank of America, N.A., as Administrative Agent
under the Credit Agreement referred to below


Ladies/Gentlemen:

         Please refer to the Second Amended and Restated Credit Agreement dated
as of August 14, 2000 among Synagro Technologies, Inc. (the "Company"), various
financial institutions and Bank of America, N.A., as Administrative Agent (as
amended, modified, extended or restated from time to time, the "Credit
Agreement"). Capitalized terms used but not defined herein have the respective
meanings set forth in the Credit Agreement.

         In accordance with Section 6.2.6 of the Credit Agreement, the Company
hereby requests an increase in the Revolving Commitment Amount from $__________
to $__________. Such increase shall be made by [increasing the Revolving
Commitment of ____________ from $________ to $________] [adding _____________ as
a Bank under the Credit Agreement with a Revolving Commitment of $____________]
as set forth in the letter attached hereto. Such increase shall be effective
three Business Days after the date that the Administrative Agent accepts the
letter attached hereto or such other date as is agreed among the Company, the
Administrative Agent and the [increasing] [new] Bank.

                                       Very truly yours,


                                       SYNAGRO TECHNOLOGIES, INC.


                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------


                                      I-1
<PAGE>


                              ANNEX I TO EXHIBIT I

                                     [Date]


Bank of America, N.A., as Administrative Agent
under the Credit Agreement referred to below

Ladies/Gentlemen:

         Please refer to the letter dated __________, 20__ from Synagro
Technologies, Inc. (the "Company") requesting an increase in the Revolving
Commitment Amount from $__________ to $__________ pursuant to Section 6.2.6 of
the Second Amended and Restated Credit Agreement dated as of August 14, 2000
among the Company, various financial institutions and Bank of America, N.A., as
Administrative Agent (as amended, modified, extended or restated from time to
time, the "Credit Agreement"). Capitalized terms used but not defined herein
have the respective meanings set forth in the Credit Agreement.

         The undersigned hereby confirms that it has agreed to increase its
Revolving Commitment under the Credit Agreement from $__________ to $__________
effective on the date which is three Business Days after the acceptance hereof
by the Administrative Agent or on such other date as may be agreed among the
Company, the Administrative Agent and the undersigned.

                                       Very truly yours,

                                       [NAME OF INCREASING BANK]


                                       By:
                                          --------------------------------------
                                       Title:
                                             -----------------------------------

Accepted as of

---------, ----

BANK OF AMERICA, N.A., as
Administrative Agent

By:
   --------------------------------------
Name:
     ------------------------------------
Title:
      -----------------------------------


                                      I-2
<PAGE>


                              ANNEX II TO EXHIBIT I

                                     [Date]


Bank of America, N.A., as Administrative Agent
under the Credit Agreement referred to below

Ladies/Gentlemen:

         Please refer to the letter dated __________, 20___ from Synagro
Technologies, Inc. (the "Company") requesting an increase in the Revolving
Commitment Amount from $__________ to $__________ pursuant to Section 6.2.6 of
the Second Amended and Restated Credit Agreement dated as of August 14, 2000
among the Company, various financial institutions and Bank of America, N.A., as
Administrative Agent (as amended, modified, extended or restated from time to
time, the "Credit Agreement"). Capitalized terms used but not defined herein
have the respective meanings set forth in the Credit Agreement.

         The undersigned hereby confirms that it has agreed to become a Bank
under the Credit Agreement with a Revolving Commitment of $__________ effective
on the date which is three Business Days after the acceptance hereof, and
consent hereto, by the Administrative Agent or on such other date as may be
agreed among the Company, the Administrative Agent and the undersigned.

         The undersigned (a) acknowledges that it has received a copy of the
Credit Agreement and the Schedules and Exhibits thereto, together with copies of
the most recent financial statements delivered by the Company pursuant to the
Credit Agreement, and such other documents and information as it has deemed
appropriate to make its own credit and legal analysis and decision to become a
Bank under the Credit Agreement; and (b) agrees that it will, independently and
without reliance upon the Administrative Agent or any other Bank and based on
such documents and information as it shall deem appropriate at the time,
continue to make its own credit and legal decisions in taking or not taking
action under the Credit Agreement.

         The undersigned represents and warrants that (i) it is duly organized
and existing and it has full power and authority to take, and has taken, all
action necessary to execute and deliver this letter and to become a Bank under
the Credit Agreement; and (ii) no notices to, or consents, authorizations or
approvals of, any Person are required (other than any already given or obtained)
for its due execution and delivery of this letter and the performance of its
obligations as a Bank under the Credit Agreement.

         The undersigned agrees to execute and deliver such other instruments,
and take such other actions, as the Administrative Agent may reasonably request
in connection with the transactions contemplated by this letter.



                                      I-3
<PAGE>



         The following administrative details apply to the undersigned:

                  (A)      Notice Address:

                           Legal name:
                                      ----------------------------------
                           Address:
                                   -------------------------------------
                           Attention:
                                     -----------------------------------
                           Telephone: (    )
                                      ----------------------------------
                           Facsimile: (    )
                                      ----------------------------------
                  (B)      Payment Instructions:

                           Account No.:
                                       ---------------------------------
                                    At:
                                       ---------------------------------

                                       ---------------------------------

                                       ---------------------------------

                           Reference:
                                      ----------------------------------
                           Attention:
                                      ----------------------------------

         The undersigned acknowledges and agrees that, on the date on which the
undersigned becomes a Bank under the Credit Agreement as set forth in the second
paragraph hereof, the undersigned will be bound by the terms of the Credit
Agreement as fully and to the same extent as if the undersigned were an original
Bank under the Credit Agreement.

                                              Very truly yours,

                                              [NAME OF NEW BANK]


                                              By:
                                                 -------------------------------
                                              Title:
                                                    ----------------------------



                                      I-4
<PAGE>



Accepted and consented to as of
______________, 20___

BANK OF AMERICA, N.A.,
  as Administrative Agent


By:
   ---------------------------------
Name:
     -------------------------------
Title:
      ------------------------------



                                      I-5
<PAGE>



                                  SCHEDULE 2.1

                              BANKS AND PERCENTAGES

<Table>
<Caption>
                              Revolving       Acquisition     Term Loan A      Term Loan B       Revolving        Acquisition
         Bank                Commitment         Amount          Amount            Amount         Percentage        Percentage
------------------------   --------------   --------------   --------------   --------------   --------------    --------------
<S>                        <C>              <C>              <C>              <C>                  <C>               <C>
Bank of America, N.A       $11,921,546.69   $ 4,397,231.37   $ 2,371,439.82   $ 4,764,078.45       23.2253427%       11.6697901%
The Bank of Nova Scotia    $ 6,250,000.00   $ 3,517,785.09   $ 3,497,151.91   $ 6,780,086.42       12.1761375%        9.3358321%
Ark II CLO 2001-1,
Limited                    $         0.00   $         0.00   $         0.00   $14,139,146.51        0.0000000%        0.0000000%
CoBank ACB                 $ 4,653,732.44   $ 2,638,338.82   $ 2,622,863.91   $ 5,085,064.82        9.0663178%        7.0018741%
Fleet Capital
Corporation                $ 2,787,106.46   $ 3,517,785.09   $ 3,497,151.91   $ 6,780,086.42        5.4297906%        9.3358321%
Heller Financial, Inc.     $ 1,400,000.00   $ 1,582,579.60   $         0.00   $ 7,511,421.59        2.7274548%        4.2000000%
IBJ Whitehall Bank &
Trust Company              $ 1,532,908.55   $ 1,934,781.80   $ 1,923,433.55   $ 3,729,047.53        2.9863848%        5.1347076%
JH Whitney Market
Value Fund L.P.            $         0.00   $         0.00   $         0.00   $ 4,418,483.28        0.0000000%        0.0000000%
Key Corporate Capital
Inc.                       $ 4,521,739.13   $ 5,707,175.81   $ 5,673,700.99   $ 4,418,483.28        8.8091708%       15.1462451%
Keyport Life Insurance
Company                    $         0.00   $         0.00   $         0.00   $ 2,651,089.97        0.0000000%        0.0000000%
LaSalle Bank National
Association                $ 3,391,304.35   $ 4,280,381.86   $ 4,255,275.74   $ 4,418,483.28        6.6068781%       11.3596838%
SRF Trading, Inc.          $         0.00   $         0.00   $         0.00   $ 1,325,544.98        0.0000000%        0.0000000%
SRF 2000 LLC               $         0.00   $         0.00   $         0.00   $ 1,767,393.32        0.0000000%        0.0000000%


<Caption>


                            Term Loan A        Term Loan B         Total
         Bank                Percentage        Percentage        Percentage
------------------------   --------------    --------------    --------------
<S>                             <C>               <C>              <C>
Bank of America, N.A            6.6082298%        5.3910790%       10.9976624%
The Bank of Nova Scotia         9.7451275%        7.6724138%        9.3990626%
Ark II CLO 2001-1,
Limited                         0.0000000%       16.0000000%        6.6298112%
CoBank ACB                      7.3088456%        5.7543104%        7.0334634%
Fleet Capital
Corporation                     9.7451275%        7.6724138%        7.7753203%
Heller Financial, Inc.          0.0000000%        8.5000000%        4.9206115%
IBJ Whitehall Bank &
Trust Company                   5.3598201%        4.2198276%        4.2764262%
JH Whitney Market
Value Fund L.P.                 0.0000000%        5.0000000%        2.0718160%
Key Corporate Capital
Inc.                           15.8102767%        5.0000000%        9.5285139%
Keyport Life Insurance
Company                         0.0000000%        3.0000000%        1.2430896%
LaSalle Bank National
Association                    11.8577075%        5.0000000%        7.6643394%
SRF Trading, Inc.               0.0000000%        1.5000000%        0.6215448%
SRF 2000 LLC                    0.0000000%        2.0000000%        0.8287264%
</Table>



                                      I-6
<PAGE>



<Table>
<Caption>
                                Revolving      Acquisition      Term Loan A      Term Loan B       Revolving        Acquisition
         Bank                  Commitment        Amount            Amount          Amount          Percentage        Percentage
--------------------------   --------------   --------------   --------------   --------------   --------------    --------------
<S>                          <C>              <C>              <C>              <C>                   <C>               <C>
Liberty-Stein Roe
Advisor Floating Rate
Advantage Fund               $         0.00   $         0.00   $         0.00   $ 1,325,544.98        0.0000000%        0.0000000%
Stein Roe & Farnham
CLO I Ltd.                   $         0.00   $         0.00   $         0.00   $ 1,325,544.98        0.0000000%        0.0000000%
Stein Roe Floating Rate
Limited Liability
Company                      $         0.00   $         0.00   $         0.00   $ 3,534,786.63        0.0000000%        0.0000000%
SunTrust Bank                $ 3,483,883.07   $ 4,397,231.36   $ 4,371,439.86   $ 8,475,108.04        6.7872383%       11.6697901%
U.S. Bank National
Association                  $ 6,387,685.85   $ 5,707,175.81   $ 5,673,700.99   $         0.00       12.4443746%       15.1462451%
Capital Farm Credit          $ 5,000,000.00   $         0.00   $ 2,000,000.00   $ 3,000,000.00        9.7409100%        0.0000000%
Denali Capital CLO I,
Ltd.                         $         0.00   $         0.00   $         0.00   $ 2,920,271.23        0.0000000%        0.0000000%

        TOTALS               $51,329,907.00   $37,680,467.00   $35,886,159.00   $88,369,666.00      100.0000000%      100.0000000%


<Caption>


                              Term Loan A        Term Loan B         Total
         Bank                  Percentage        Percentage        Percentage
--------------------------   --------------    --------------    --------------
<S>                               <C>               <C>               <C>
Liberty-Stein Roe
Advisor Floating Rate
Advantage Fund                    0.0000000%        1.5000000%        0.6215448%
Stein Roe & Farnham
CLO I Ltd.                        0.0000000%        1.5000000%        0.6215448%
Stein Roe Floating Rate
Limited Liability
Company                           0.0000000%        4.0000000%        1.6574528%
SunTrust Bank                    12.1814093%        9.5905173%        9.7191503%
U.S. Bank National
Association                      15.8102767%        0.0000000%        8.3316358%
Capital Farm Credit               5.5731794%        3.3948301%        4.6889756%
Denali Capital CLO I,
Ltd.                              0.0000000%        3.3046082%        1.3693080%

        TOTALS                  100.0000000%      100.0000000%      100.0000000%
</Table>





                                      I-7