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Exhibit 4.3  

 
 

AMENDMENT TO INDENTURE    
    

        This Amendment to Indenture (this "Amendment"), dated as of January 30, 2004, is made by and between Great Lakes Dredge & Dock Corporation, a
Delaware corporation (the "Company"), and BNY Midwest Trust Company, as trustee (the "Trustee") under the Indenture (as defined below). Capitalized terms used herein without definition shall have the
meanings assigned to them in the Indenture. 

W I T N E S S E T H 

        WHEREAS,
the Company, the Subsidiary Guarantors and the Trustee are parties to that certain Indenture, dated as of December 22, 2003, as supplemented by the Supplemental Indenture
dated as of December 22, 2003 (the "Indenture"); 

        WHEREAS,
pursuant to Sections 9.01(1) and (8) of the Indenture, the Trustee and the Company are authorized to amend or supplement the Indenture without the consent of any Holder
to cure any ambiguity, defect or inconsistency or to conform any provision of the Indenture to the "Description of Notes" contained in the Offering Memorandum; 

        WHEREAS,
the "Description of Notes" under the captions "Subsidiary Guarantees" and "Merger, Consolidation or Sale of Assets" has not been accurately reflected in Sections 5.02 and
10.05 of the Indenture, and in the case of each of Sections 5.02 and 10.05, the Indenture contains an inconsistency; 

        NOW
THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Company, and the Trustee mutually
covenant and agree as follows: 

        1.    Amendment to Section 5.02.    Section 5.02 of the Indenture is deleted in its entirety and
replaced with the following notation "Intentionally Omitted." 

        2.    Amendment to Section 10.05.    Section 10.05 of the Indenture is replaced in its entirety with the
following: 

        "Section 10.05    Releases Following Merger, Consolidation or Sale of Assets, Etc. 

        In
the event of a sale or other disposition of all or substantially all of the assets of any Subsidiary Guarantor, by way of merger, consolidation or otherwise, or a sale or other
disposition of Capital Stock of any Subsidiary Guarantor such that such Subsidiary Guarantor ceases to be a Subsidiary of the Company, the Subsidiary Guarantor (in the event of a sale or other
disposition, by way of merger, consolidation or otherwise, of Capital Stock of the Subsidiary Guarantor) or the corporation or other entity acquiring the property (in the event of a sale or other
disposition of all or substantially all of the assets of the Subsidiary Guarantor) shall be released and relieved of any and all obligations under its Subsidiary Guarantee (and, in the event of a
disposition of assets, any Liens in favor of the Holders will be released); provided that the Net Proceeds of the sale or other disposition shall be applied in accordance with the applicable
provisions of this Indenture, including without limitation Section 4.12. If a Restricted Subsidiary is designated as an Unrestricted Subsidiary in accordance with the provisions of
Section 4.17, such Subsidiary shall be released and relieved of any obligations under its Subsidiary Guarantee upon the effectiveness of the designation. Upon delivery by the Company to the
Trustee of an Officers' Certificate and an Opinion of Counsel to the effect that such sale or other disposition was made by the Company in accordance with the provisions of this Indenture, including
without limitation Section 4.12, the Trustee shall execute any documents reasonably required in order to evidence the release of any Subsidiary Guarantor from its obligations under its
Subsidiary Guarantee. 

 

        Any
Subsidiary Guarantor not released from its obligations under its Subsidiary Guarantee shall remain liable for the full amount of principal of and interest on the Notes and for the
other obligations of any Subsidiary Guarantor under this Indenture as provided in this Article 10." 

        3.    Governing Law.    THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS AMENDMENT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY. 

        4.    Counterparts.    The parties may sign any number of copies of this Amendment. Each signed copy shall be an
original, but all of them together represent the same agreement. 

        5.    Effect of Headings.    The headings in this Amendment have been inserted for convenience of reference only, are
not to be considered a part of this Amendment and shall in no way modify or restrict any of the terms or provisions hereof. 

        6.    Trustee.    The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or
sufficiency of this Amendment or for or in respect of the recitals contained herein, all of which recitals are made solely by the Company. 

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        IN
WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed and attested, all as of January 30, 2004. 

	 	 	GREAT LAKES DREDGE & DOCK CORPORATION
	

 	
 	

By:	
 	

/s/  DEBORAH A. WENSEL      

	 	 	 	 	Name:	 	Deborah A. Wensel
	 	 	 	 	Title:	 	Senior Vice President, Chief Financial Officer and Treasurer
	

 	
 	

BNY MIDWEST TRUST COMPANY, AS TRUSTEE
	

 	
 	

By:	
 	

/s/  MARY CALLAHAN      

	 	 	 	 	Name:	 	Mary Callahan
	 	 	 	 	Title:	 	Assistant Vice President

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Exhibit 4.4  

 
 

SUPPLEMENTAL INDENTURE    
    

        This Supplemental Indenture (this "Supplemental Indenture"), dated as of February 27, 2004, by and among
JDC Soil Management & Development Inc., a Massachusetts corporation (the "Guaranteeing Subsidiary"), which is a direct subsidiary of Great
Lakes Dredge & Dock Corporation, a Delaware corporation (the "Issuer"), the Issuer, Great Lakes Dredge & Dock Company, a New Jersey
corporation, Great Lakes Caribbean Dredging, Inc., a Delaware corporation, Dawson Marine Services Company, a Delaware corporation, North American Site Developers, Inc., a Massachusetts
corporation, and Fifty-Three Dredging Corporation, a New Jersey corporation (each an "Existing Guarantor" and, collectively, the
"Existing Guarantors") and BNY Midwest Trust Company, as trustee under the Indenture referred to below (the
"Trustee"). 

W I T N E S S E T H 

        WHEREAS,
the Issuer and the Existing Guarantors have previously executed and delivered to the Trustee an indenture, dated as of December 22, 2003, as supplemented and amended from
time to time (the "Indenture"), providing for the issuance of an aggregate principal amount of up to $175,000,000 of 73/4% Senior
Subordinated Notes due 2013 (the "Notes"); 

        WHEREAS,
pursuant to Section 4.19 of the Indenture, the Guaranteeing Subsidiary is required to become a Subsidiary Guarantor and execute a supplemental indenture to the Indenture;
and 

        WHEREAS,
pursuant to Section 9.06 of the Indenture, the Trustee is authorized to execute and deliver this Supplemental Indenture. 

        NOW
THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the parties hereto mutually covenant and
agree for the equal and ratable benefit of the Holders of the Notes as follows: 

        1.    Capitalized Terms.    Capitalized terms used herein without definition shall have the meanings assigned to them
in the Indenture. 

        2.    Agreement to Guarantee.    The Guaranteeing Subsidiary hereby agrees as follows: 

	(1)
	Along
with all Subsidiary Guarantors named in the Indenture, to unconditionally guarantee (each such guarantee to be referred to herein as a "Subsidiary
Guarantee") to each Holder of a Note authenticated and delivered by the Trustee and to the Trustee and its successors and assigns, irrespective of the validity and
enforceability of this Supplemental Indenture, the Notes or the obligations of the Issuer hereunder or thereunder, that: (i) the principal of and interest on the Notes will be promptly paid in
full when due, whether at maturity, by acceleration, redemption or otherwise, and interest on the overdue principal of and interest on the Notes, if any, if lawful, and all other obligations of the
Issuer to the Holders or the Trustee hereunder or thereunder will be promptly paid in full or performed, all in accordance with the terms hereof and thereof; and (ii) in case of any extension
of time of payment or renewal of any Notes or any of such other obligations, that same will be promptly paid in full when due or performed in accordance with the terms of the extension or renewal,
whether at stated maturity, by acceleration or otherwise. Failing payment when due of any amount so guaranteed or any performance so guaranteed for whatever reason, the Guaranteeing Subsidiary shall
be jointly and severally obligated to pay the same immediately. The Guaranteeing Subsidiary agrees that this is a guarantee of payment and not a guarantee of collection.

	(2)
	The
Guaranteeing Subsidiary hereby agrees that its obligations hereunder shall be unconditional, irrespective of the validity, regularity or enforceability of the Notes or this
Supplemental Indenture, the absence of any action to enforce the same, any waiver or consent by any Holder of the Notes with respect to any provisions hereof or thereof, the 

recovery
of any judgment against the Issuer, any action to enforce the same or any other circumstance which might otherwise constitute a legal or equitable discharge or defense of any other Subsidiary
Guarantor. The Guaranteeing Subsidiary hereby waives diligence, presentment, demand of payment, filing of claims with a court in the event of insolvency or bankruptcy of the Issuer, any right to
require a proceeding first against the Issuer, protest, notice and all demands whatsoever and covenants that its Subsidiary Guarantee shall not be discharged except by complete performance of the
obligations contained in the Notes, the Indenture and this Subsidiary Guarantee. 

	(3)
	If
any Holder or the Trustee is required by any court or otherwise to return to the Issuer, to any Subsidiary Guarantor, or any custodian, trustee, liquidator or other similar
official acting in relation to either the Issuer or to any Subsidiary Guarantor, any amount paid by either to the Trustee or such Holder, the Subsidiary Guarantee, to the extent theretofore
discharged, shall be reinstated in full force and effect.

	(4)
	The
Guaranteeing Subsidiary agrees that it shall not be entitled to any right of subrogation in relation to the Holders in respect of any Subsidiary Guarantee until payment in full of
all obligations guaranteed under this Supplemental Indenture. The Guaranteeing Subsidiary further agrees that, as between it, on the one hand, and the Holders and the Trustee, on the other hand,
(x) the maturity of the obligations guaranteed hereby may be accelerated as provided in Article 6 of the Indenture for the purposes of this Subsidiary Guarantee, notwithstanding any
stay, injunction or other prohibition preventing such acceleration in respect of the obligations guaranteed hereby, and (y) in the event of any declaration of acceleration of such obligations
as provided in Article 6 of the Indenture, such obligations (whether or not due and payable) shall forthwith become due and payable by the Guaranteeing Subsidiary for the purpose of this
Subsidiary Guarantee. The Guaranteeing Subsidiary shall have the right to seek contribution from any non-paying Subsidiary Guarantor so long as the exercise of such right does not impair
the rights of the Holders under this Subsidiary Guarantee. 

        3.    Incorporation of Terms of Indenture.    The obligations of the Guaranteeing Subsidiary under the Subsidiary
Guarantee shall be governed in all respects by the terms of the Indenture and shall constitute a Subsidiary Guarantee thereunder. Each of the parties hereto shall be bound by the terms of the
Indenture as they relate to the Subsidiary Guarantees. 

        4.    No Recourse Against Others.    No past, present or future director, officer, employee, incorporator or
stockholder of the Guaranteeing Subsidiary shall have any person liability under this Subsidiary Guarantee by reason of his, her or its status as such director, officer, employee, incorporator or
stockholder. 

        5.    Governing Law.    THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS
SUPPLEMENTAL INDENTURE WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY. 

        6.    Counterparts.    The parties may sign any number of copies of this Supplemental Indenture. Each signed copy
shall be an original, but all of them together represent the same agreement. 

        7.    Effect of Headings.    The headings in this Supplemental Indenture have been inserted for convenience of
reference only, are not to be considered a part of this Supplemental Indenture and shall in no way modify or restrict any of the terms or provisions hereof. 

        8.    Disclaimer by Trustee.    The Trustee makes no representation as to the validity of this Supplemental Indenture
or the proper authorization or due execution of this Supplemental Indenture by the Issuer, the Existing Guarantors or the Guaranteeing Subsidiary. 

        IN
WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed and attested, all as of February 27, 2004. 

	 	 	JDC SOIL MANAGEMENT & DEVELOPMENT INC.
	

 	
 	

By:	
 	

/s/  DONALD J. LUCE      

	 	 	 	 	Name:	 	Donald J. Luce
	 	 	 	 	Title:	 	Assistant Clerk and Assistant Treasurer
	

 	
 	

GREAT LAKES DREDGE & DOCK CORPORATION
	

 	
 	

By:	
 	

/s/  DEBORAH A. WENSEL      

	 	 	 	 	Name:	 	Deborah A. Wensel
	 	 	 	 	Title:	 	Senior Vice President
	

 	
 	

GREAT LAKES DREDGE & DOCK COMPANY
	

 	
 	

By:	
 	

/s/  DEBORAH A. WENSEL      

	 	 	 	 	Name:	 	Deborah A. Wensel
	 	 	 	 	Title:	 	Senior Vice President
	

 	
 	

GREAT LAKES CARIBBEAN DREDGING, INC.
	

 	
 	

By:	
 	

/s/  DEBORAH A. WENSEL      

	 	 	 	 	Name:	 	Deborah A. Wensel
	 	 	 	 	Title:	 	Senior Vice President
	

 	
 	

DAWSON MARINE SERVICES COMPANY
	

 	
 	

By:	
 	

/s/  DEBORAH A. WENSEL      

	 	 	 	 	Name:	 	Deborah A. Wensel
	 	 	 	 	Title:	 	Senior Vice President
	 	 	 	 	 	 	 

	

 	
 	

NORTH AMERICAN SITE DEVELOPERS, INC.
	

 	
 	

By:	
 	

/s/  DEBORAH A. WENSEL      

	 	 	 	 	Name:	 	Deborah A. Wensel
	 	 	 	 	Title:	 	Vice President
	

 	
 	

FIFTY-THREE DREDGING CORPORATION
	

 	
 	

By:	
 	

/s/  PAUL DINQUEL      

	 	 	 	 	Name:	 	Paul Dinquel
	 	 	 	 	Title:	 	Vice President
	

 	
 	

BNY MIDWEST TRUST COMPANY, as Trustee
	

 	
 	

By:	
 	

/s/  D. G. DONOVAN      

	 	 	 	 	Name:	 	D. G. Donovan
	 	 	 	 	Title:	 	Vice President

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SUPPLEMENTAL INDENTURE

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