Exhibit 4.1


 


THIRD
SUPPLEMENTAL INDENTURE


 


This Supplemental Indenture (this “Supplemental
Indenture”), dated as of December 2, 2005, by and among NASDI Holdings
Corporation, a Delaware corporation (the “Guaranteeing Subsidiary”),
Great Lakes Dredge & Dock Corporation, a Delaware corporation (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, Fifty-Three Dredging Corporation, a New Jersey
corporation, JDC Soil Management & Development Inc., a Massachusetts
corporation and Great Lakes Dredge & Dock Company, LLC, a Delaware
limited liability company (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 4.16 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 personal 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 or sufficiency 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.


 


The recitals and statements herein are deemed to be
those of the Issuer, Guaranteeing Subsidiary and the Existing Guarantors and
not of the Trustee.


 





















 


IN WITNESS WHEREOF, the parties hereto have caused
this Supplemental Indenture to be duly executed and attested, all as of December 2,
2005.


 


 


	
   

  	
  NASDI HOLDINGS
  CORPORATION

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Name: Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Title: Sr. Vice
  President and CFO

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  GREAT LAKES
  DREDGE & DOCK

  CORPORATION

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Name: Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Title: Sr. Vice
  President and CFO

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  GREAT LAKES
  DREDGE & DOCK COMPANY

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Name: Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Title: Sr. Vice
  President and CFO

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  GREAT LAKES
  CARIBBEAN DREDGING, INC.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Name: Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Title: Sr. Vice
  President and CFO

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  DAWSON MARINE
  SERVICES COMPANY

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Name: Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Title: Sr. Vice
  President and CFO

  	
   

  



 





















 


	
   

  	
  NORTH AMERICAN
  SITE DEVELOPERS, INC.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Name: Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Title: Sr. Vice
  President and CFO

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  FIFTY-THREE
  DREDGING CORPORATION

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Paul Dinquel

  	
   

  
	
   

  	
   

  	
  Name: Paul
  Dinquel

  	
   

  
	
   

  	
   

  	
  Title: V.P.

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  JDC SOIL
  MANAGEMENT & DEVELOPMENT

  INC.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Name: Deborah A.
  Wensel

  	
   

  
	
   

  	
   

  	
  Title: Sr. Vice
  President and CFO

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  GREAT LAKES
  DREDGE & DOCK COMPANY,

  LLC

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
  Name:

  	
   

  
	
   

  	
   

  	
  Title:

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  BNY MIDWEST
  TRUST COMPANY, AS TRUSTEE

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ M. Callahan

  	
   

  
	
   

  	
   

  	
  Name: M.
  Callahan

  	
   

  
	
   

  	
   

  	
  Title: Vice
  President