EXHIBIT 2.3 AMENDMENT NO. 4 TO THE ASSET PURCHASE AGREEMENT AMENDMENT NO. 4, dated May 3, 2002 (this "Amendment") to the ASSET PURCHASE AGREEMENT (the "Original Agreement"), dated as of January 23, 2002, as amended, by and among THE SHAW GROUP INC., a Louisiana corporation (together with its Designee(s), if any, "Buyer"), and THE IT GROUP, INC., a Delaware corporation ("ITG") and the Subsidiaries (as defined in the Agreement) of ITG that are listed on the signature pages to this Amendment (together with ITG, "Sellers"). RECITALS WHEREAS, capitalized terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the Agreement; WHEREAS, the Parties previously amended the Original Agreement on January 24, 2002, pursuant to Amendment No. 1 to the Asset Purchase Agreement (the "First Amendment"); WHEREAS, the Parties further amended the Original Agreement on January 29, 2002, pursuant to Amendment No. 2 to the Asset Purchase Agreement (the "Second Amendment"); WHEREAS, the Parties further amended the Original Agreement on April 30, 2002, pursuant to a Letter Agreement to the Asset Purchase Agreement (the "Letter Agreement"); WHEREAS, the Parties further amended the Original Agreement on May 2, 2002, pursuant to Amendment No. 3 (the "Third Amendment", together with the Original Agreement, First Amendment, the Second Amendment and the Letter Agreement, the "Agreement"); WHEREAS, Section 2.08(a) of the Agreement currently contemplates that at least two days prior to the Closing Date, ITG will cause the Agreement to be amended to add as Sellers any of its Subsidiaries that have any right, title or interest in or to any of the Assets; WHEREAS, the Parties desire to amend the Agreement to join and bind certain additional Subsidiaries of ITG as Sellers; and WHEREAS, Section 9.12 of the Agreement provides that the Agreement may be amended by execution of a written instrument executed by the Parties thereto. AGREEMENT NOW, THEREFORE, in consideration of the foregoing premises, and the agreements, covenants, representations and warranties contained in the Agreement and herein, and other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged and accepted, the Parties, intending to be legally bound, hereby agree as follows: 1. Each Subsidiary of the Company listed on the signature pages of this Amendment (the "Additional Selling Subsidiaries") agrees (i) to join and become a Party to the Agreement and (ii) to be bound by all of the terms and obligations set forth in the Agreement as of the 1 Effective Date. Each Additional Selling Subsidiary hereby ratifies all actions heretofore taken or performed by ITG to the extent taken or performed in connection with the Agreement and the Transactions. 2. Except as specifically amended hereby, the terms and provisions of the Agreement shall continue and remain in full force and effect and the valid and binding obligation of the Parties thereto in accordance with its terms. All references in the Agreement (and in any other agreements, documents and instruments entered into in connection therewith) to the "Agreement" shall be deemed for all purposes to refer to the Agreement, as amended. 3. This Amendment may be executed in one or more counterparts, each of which shall be an original, with the same effect as of the signatures hereto and thereto were upon the same instrument. 4. This Amendment shall be governed by and construed in accordance with the laws of the State of Delaware without regard to the conflicts of law rules of such state. [SIGNATURES ON NEXT PAGE] 2 IN WITNESS WHEREOF, the Parties have executed this Amendment and caused the same to be duly delivered on their behalf on the day and year first written above. THE IT GROUP, INC. By: /s/ HARRY J. SOOSE, JR. --------------------------------------- Its: SVP & CFO ------------------------------------- THE SHAW GROUP INC. By: /s/ GARY P. GRAPHIA --------------------------------------- Its: Secretary ------------------------------------- 37-02 COLLEGE POINT BOULEVARD, LLC ADVANCED ANALYTICAL SOLUTIONS, INC. E-COM SOLUTIONS, INC. EMPIRE STATE I, LLC EMPIRE STATE II, LLC EVAP TECHNOLOGIES, LLC EVERGREEN ACQUISITION SUB I, INC. GROUNDWATER TECHNOLOGY, INC. IT C&V OPERATIONS, INC. IT E&C OPERATIONS, INC. IT ENVIRONMENTAL AND FACILITIES, INC. IT INTERNATIONAL HOLDINGS, INC. IT INTERNATIONAL INVESTMENTS, INC. IT INTERNATIONAL INVESTMENTS, INC. IT INTERNATIONAL OPERATIONS, INC. IT INVESTMENT HOLDINGS, INC. JERNEE MILL ROAD, LLC KIP I, LLC LANDBANK ACQUISITION I, LLC LANDBANK ACQUISITION II, LLC LANDBANK ACQUISITION III, LLC LANDBANK ENVIRONMENTAL PROPERTIES, LLC LANDBANK REMEDIATION CORP. LANDBANK, INC. LANDBANK WETLANDS, LLC 3 MARCONI WARTBURG, LLC MILLSTONE RIVER WETLANDS SERVICES, INC. NORTHEAST RESTORATION COMPANY, LLC ORGANIC WASTE TECHNOLOGIES, INC. OTAY MESA VENTURES I, LLC PHR ENVIRONMENTAL CONSULTANTS, INC. RARITAN VENTURE I, LLC THE DORCHESTER GROUP, LLC U.S. WETLAND SERVICES, LLC WHIPPANY VENTURE I, LLC WYCKOFF'S MILLS, LLC AMERICAN LANDFILL SUPPLY CO., INC. BENECIA NORTH GATEWAY, LLC EMCON EMCON INDUSTRIAL SERVICES, INC. ENTERPRISE, ENVIRONMENTAL & EARTHWORKS, INC. FLUOR DANIEL ENVIRONMENTAL SERVICES, INC. (FDESI) GRADIENT CORPORATION IT ALASKA, INC. IT BAKER LLC IT CORPORATION IT CORPORATION OF NORTH CAROLINA, INC. IT - TULSA HOLDINGS, INC. ITGTECH JELLINEK, SCHWARTZ & CONNOLLY, INC. JSC INTERNATIONAL, INC. KATO ROAD, LLC KEYSTONE RECOVERY, INC. LFG SPECIALTIES, INC. MONTEREY LANDFILL GAS COMPANY NATIONAL EARTH PRODUCTS, INC. NORTHERN CALIFORNIA DEVELOPMENT LIMITED OHM CORPORATION OHM REMEDIATION SERVICES CORP. OHM REMEDIATION SERVICES OF CANADA, LTD. PACIFIC ENVIRONMENTAL GROUP, INC. SIELKEN, INC. SUBMERGED LANDS, LLC W&H PACIFIC, INC. WEHRAN NEW YORK, INC. 4 HL NEWHALL, LLC By: /s/ JAMES M. REDWINE ----------------------------------------- Name: James M. Redwine --------------------------------------- Title: Authorized Signatory -------------------------------------- CHIMENTO WETLANDS I, LLC By: /s/ JAMES M. REDWINE ----------------------------------------- Name: James M. Redwine --------------------------------------- Title: President -------------------------------------- 5