EXHIBIT 5.1

                                 April 26, 2002

Synagro Technologies, Inc.
1800 Bering Drive, Suite 1000
Houston, Texas  77037

Gentlemen:

         We have acted as special counsel to Synagro Technologies, Inc., a
Delaware corporation (the "Company") and the subsidiaries of the Company named
in Schedule I hereto (the "Guarantors"), in connection with the preparation and
filing of the Registration Statement on Form S-4 by the Company with the
Securities and Exchange Commission (the "Commission") under the Securities Act
of 1933, as amended (the "Act"), on April 26, 2002 (the "Registration
Statement"), with respect to the issuance by the Company of up to $150,000,000
aggregate principal amount of its 9 1/2% Senior Subordinated Notes due 2009 (the
"New Notes") in exchange for up to $150,000,000 in aggregate principal amount of
its outstanding 9 1/2% Senior Subordinated Notes due 2009 (the "Old Notes")
and the issuance by the Guarantors of guarantees (the "Guarantees") with respect
to the New Notes. The New Notes and the Guarantees are to be issued in
accordance with the provisions of the Indenture, dated as of April 17, 2002 (the
"Indenture"), by and between the Company, the guarantors signatory thereto, and
Wells Fargo Bank Minnesota, National Association, as trustee (the "Trustee").
The New Notes and the Guarantees are to be issued pursuant to an exchange offer
(the "Exchange Offer") by the Company to holders of the issued and outstanding
Old Notes, as contemplated by the Exchange and Registration Rights Agreement,
dated as of April 17, 2002 (the "Registration Rights Agreement"), by and between
the Company, the guarantors signatory thereto, Lehman Brothers Inc. and Banc of
America Securities LLC.

         This opinion is being furnished in accordance with the requirements of
Item 601(b)(5) of Regulation S-K under the Act.

         In our capacity as counsel to the Company and the Guarantors in
connection with the Exchange Offer, we have examined the Registration
Statement, the Indenture (including each guarantee set forth therein) and the
forms of the New Notes, each of which will be filed with the Commission as an
exhibit to the Registration Statement. We have also examined originals, or
copies certified or otherwise identified, of (i) the Company's Restated
Certificate of Incorporation and Amended and Restated Bylaws, each as amended to
date, (ii) corporate records of the Company, including minute books of the
Company as furnished to us by the Company, (iii) the charter, bylaws or other
governing documents of each of the Guarantors, (iv) corporate or partnership
records of each of the Guarantors, including minute books of each of the
Guarantors furnished to us by the Guarantors, (v) certificates of public
officials and of representatives of the Company and the Guarantors, and (vi)
statutes and other instruments and documents as a basis for the opinions
hereinafter expressed. In giving the opinions set forth below, we have relied
upon certificates of officers or other representatives of the Company and the
Guarantors with respect to the accuracy of the factual matters contained in such
certificates. In making our examination, we have assumed that all signatures on
documents examined by us are genuine, all documents submitted to us as originals
are authentic and complete and all documents submitted to us as certified or
photostatic copies conform to the originals thereof. As to any facts material to
the opinion expressed herein which we have not independently established or
verified, we have relied upon oral or written statements and representations of
officers and other representatives of the Company and others.

         Our opinion set forth herein is limited to the laws of the State of New
York (other than municipal and local ordinances and regulations) that are
normally applicable to transactions of the type contemplated by the Exchange
Offer and to the extent that judicial or regulatory orders or decrees or
consents, approvals, licenses, authorizations, validations, filings, recordings
or registrations with governmental authorities are relevant, to those required
under such laws. We do not express any opinion with respect to the law of any
jurisdiction other than as set forth above or as to the effect of any such other
law on the opinion stated herein. In rendering the opinion set forth herein with
respect to the laws of the State of New York, we have relied, with your consent,
in all respects as to matters regarding the laws of the State of New York on the
opinion of counsel in such State that has been furnished to you.





Synagro Technologies, Inc.
1800 Bering Drive, Suite 1000
Houston, Texas  77037


         Based upon and subject to the foregoing, and subject to the
limitations, qualifications, exceptions and assumptions set forth herein, we are
of the opinion that when the New Notes have been duly executed by the Company,
authenticated by the Trustee in accordance with the terms of the Indenture, and
delivered upon consummation of the Exchange Offer against receipt of Old Notes
surrendered in exchange therefor in accordance with the terms of the
Registration Rights Agreement and the Indenture, the New Notes and the
Guarantees will constitute valid and binding obligations of the Company and the
Guarantors, respectively, enforceable against them in accordance with their
terms, except, to the extent that enforcement thereof may be limited by (i)
bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance or
other similar laws now or hereafter in effect affecting creditors' rights
generally and (ii) general principles of equity (regardless of whether
enforceability is considered in a proceeding at law or in equity), including
reasonableness, good faith, materiality and fair dealing, and the discretion of
the court before which any proceeding therefor may be brought.

         We hereby consent to the filing of this opinion with the SEC as an
exhibit to the Registration Statement. We also consent to the reference to our
firm under the caption "Legal matters" in the Registration Statement. In giving
this consent, we do not thereby admit that we are included in the category of
persons whose consent is required under Section 7 of the Act or the rules and
regulations of the SEC. This opinion is expressed as of the date hereof, and we
disclaim any undertaking to advise you of any subsequent changes in the facts
stated or assumed herein or of any subsequent changes in applicable law.

                                        Very truly yours,


                                        /s/ LOCKE LIDDELL & SAPP LLP
                                        ----------------------------
                                        Locke Liddell & Sapp LLP





                                   Schedule I

                                   Guarantors

<Table>
<Caption>
            EXACT NAME OF REGISTRANT                          STATE OR OTHER JURISDICTION OF
          AS SPECIFIED IN ITS CHARTER                         INCORPORATION OR ORGANIZATION
          ----------------------------                        -----------------------------
                                                           
Composting Corporation of America                                        Arkansas
Environmental Protection & Improvement Company, Inc.                     New Jersey
Fairhaven Residual Systems, Inc.                                         Delaware
Fairhaven Residuals, Limited Partnership                                 Delaware
Future - Tech Environmental Services, Inc.                               California
NETCO-Connecticut, Inc.                                                  Connecticut
NETCO-Residuals Management Systems, Inc.                                 Delaware
NETCO-Residuals Management, Limited Partnership                          Delaware
NETCO-Waterbury Systems, Inc., f/k/a NETCO-Waterbury, Inc.               Delaware
NETCO-Waterbury, Limited Partnership                                     Delaware
New England Treatment Company, Inc.                                      Rhode Island
New Haven Residuals Systems, Inc.                                        Delaware
New Haven Residuals, Limited Partnership                                 Delaware
New York Organic Fertilizer Company                                      New York
NYOFCO Holdings Inc.                                                     Delaware
Organi-Gro, Inc.                                                         Arkansas
Providence Soils, LLC                                                    Rhode Island
Residual Technologies Systems, Inc.                                      Delaware
Residual Technologies, Limited Partnership                               Delaware
Residuals Processing, Inc.                                               California
Soaring Vista Properties, Inc.                                           Maryland
</Table>





<Table>
<Caption>
            EXACT NAME OF REGISTRANT                          STATE OR OTHER JURISDICTION OF
          AS SPECIFIED IN ITS CHARTER                         INCORPORATION OR ORGANIZATION
          ----------------------------                        -----------------------------
                                                           
ST Interco, Inc.                                                         Delaware
Synagro - Baltimore L.L.C.                                               Maryland
Synagro Composting Company of California, Inc.                           California
Synagro Delaware, Inc.                                                   Delaware
Synagro Digestion, Inc.                                                  California
Synagro Management, L.P.                                                 Texas
Synagro Mid-Atlantic, Inc.                                               Delaware
Synagro Midwest - Enviroland, Inc., f/k/a Enviroland, Inc.               Michigan
Synagro Midwest, Inc.                                                    Delaware
Synagro Northeast, Inc.                                                  Delaware
Synagro of California, Inc.                                              Arizona
Synagro of Florida-A&J, Inc.                                             Florida
Synagro of Florida-Anti-Pollution, Inc.                                  Florida
Synagro of Florida-Davis Water, Inc.                                     Florida
Synagro of Florida-Ecosystems, Inc.                                      Florida
Synagro of Michigan, Inc.                                                Michigan
Synagro of Minnesota--Rehbein, Inc.                                      Minnesota
Synagro of North Carolina-Amsco, Inc.                                    North Carolina
Synagro of North Carolina-EWR, Inc.                                      North Carolina
Synagro of Texas-CDR, Inc.                                               Texas
Synagro of Texas-Vital-Cycle, Inc.                                       Wisconsin
Synagro of Wisconsin, Inc.                                               Wisconsin
Synagro Southeast, Inc.                                                  Delaware
Synagro Southwest, Inc.                                                  Delaware
Synagro Texas, Inc.                                                      Texas
</Table>




<Table>
<Caption>
            EXACT NAME OF REGISTRANT                          STATE OR OTHER JURISDICTION OF
          AS SPECIFIED IN ITS CHARTER                         INCORPORATION OR ORGANIZATION
          ----------------------------                        -----------------------------
                                                           
Synagro West, Inc.                                                       Delaware
Synagro-WWT, Inc., f/k/a Wheelabrator Water Technologies, Inc.           Maryland
Synagro WCWNJ, Inc., f/k/a Wheelabrator Clean Water New Jersey, Inc.     Delaware
</Table>