Exhibit 10.1

EXECUTION COPY

REAFFIRMATION AGREEMENT

THIS REAFFIRMATION AGREEMENT (this “Agreement”), dated as of December 26, 2006,
is by and between GREAT LAKES DREDGE & DOCK CORPORATION (f/k/a Great Lakes
Dredge & Dock Holdings Corp.), a Delaware corporation (“New GLDD”), and BANK OF
AMERICA, N.A., in its capacity as Administrative Agent (the “Administrative
Agent”) under the Credit Agreement referred to below.

W I T N E S S E T H :

WHEREAS, prior to the date hereof, New GLDD’s legal name was “Great Lakes Dredge
& Dock Holdings Corp.”;

WHEREAS, on the date hereof, (i) Great Lakes Dredge & Dock Corporation (“Legacy
GLDD”) merged with and into New GLDD with New GLDD as the survivor of such
merger  (the “Merger”) and (ii) New GLDD changed its legal name to “Great Lakes
Dredge & Dock Corporation;”

WHEREAS, upon giving effect to the Merger, New GLDD succeeded to the rights,
duties and obligations of Legacy GLDD under (i) that certain Credit Agreement
dated as of December 22, 2003 (as amended by Amendment No. 1 to Credit Agreement
dated as of September 30, 2004, Amendment No. 2 to Credit Agreement dated as of
June 13, 2005, Amendment No. 3 to Credit Agreement dated as of November 13,
2005, Amendment No. 4 to Credit Agreement dated as of March 22, 2006 and
Consent, Waiver and Amendment No. 5 to Credit Agreement dated as of August 28,
20006 and as further amended, restated, supplemented or otherwise modified and
in effect from time to time, the “Credit Agreement”) by and among New GLDD as
successor to Legacy GLDD, the Affiliates of New GLDD party thereto, the Lenders
from time to time party thereto and the Administrative Agent and (ii) each of
the other Loan Documents to which Legacy GLDD was a party; and

WHEREAS, New GLDD, as successor to Legacy GLDD, wishes to hereby expressly
reaffirm its duties and obligations under the Credit Agreement and the other
Loan Documents to which Legacy GLDD was a party;

NOW, THEREFORE, in consideration of the premises and of the mutual covenants
contained herein, and other good and valuable consideration the receipt and
adequacy of which are hereby acknowledged, the parties hereto hereby agree as
follows:

DEFINED TERMS.  TERMS CAPITALIZED HEREIN AND NOT OTHERWISE DEFINED HEREIN ARE
USED WITH THE MEANINGS ASCRIBED TO SUCH TERMS IN THE CREDIT AGREEMENT.

REAFFIRMATION OF OBLIGATIONS.  NEW GLDD HEREBY (A) EXPRESSLY REAFFIRMS ALL OF
THE DUTIES AND OBLIGATIONS OF LEGACY GLDD UNDER THE CREDIT AGREEMENT, EACH NOTE,
THE LETTERS OF CREDIT, THE COLLATERAL DOCUMENTS AND THE OTHER LOAN DOCUMENTS TO
WHICH LEGACY GLDD WAS A PARTY,

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AND (B) EXPRESSLY RECONFIRMS THE ADMINISTRATIVE AGENT’S CONTINUING LIEN IN THE
COLLATERAL GRANTED PURSUANT TO THE COLLATERAL DOCUMENTS.  NEW GLDD HEREBY
REAFFIRMS THAT, UPON THE EFFECTIVENESS OF THE MERGER, IT IS AND SHALL HEREAFTER
BE, ENTITLED TO AND LIABLE FOR EACH AND EVERY RIGHT, OBLIGATION, DUTY,
REPRESENTATION AND COVENANT OF LEGACY GLDD TO THE SAME EXTENT AS IF NEW GLDD HAD
BEEN THE ORIGINAL PARTY TO THE LOAN DOCUMENTS.

REPRESENTATIONS AND WARRANTIES.  NEW GLDD HEREBY REPRESENTS AND WARRANTS TO THE
ADMINISTRATIVE AGENT, IN EACH CASE AFTER GIVING EFFECT TO THE MERGER AND THIS
AGREEMENT, AS FOLLOWS:

NEW GLDD HAS THE RIGHT, POWER AND CAPACITY AND HAS BEEN DULY AUTHORIZED AND
EMPOWERED BY ALL REQUISITE LIMITED LIABILITY COMPANY AND MEMBER ACTION TO ENTER
INTO, EXECUTE, DELIVER AND PERFORM THIS AGREEMENT AND ALL AGREEMENTS, DOCUMENTS
AND INSTRUMENTS EXECUTED AND DELIVERED PURSUANT TO THIS AGREEMENT.

THIS AGREEMENT CONSTITUTES NEW GLDD’S LEGAL, VALID AND BINDING OBLIGATION,
ENFORCEABLE AGAINST IT, EXCEPT AS ENFORCEMENT THEREOF MAY BE SUBJECT TO THE
EFFECT OF ANY APPLICABLE BANKRUPTCY, INSOLVENCY, REORGANIZATION, MORATORIUM OR
SIMILAR LAWS AFFECTING CREDITORS’ RIGHTS GENERALLY AND GENERAL PRINCIPLES OF
EQUITY (REGARDLESS OF WHETHER SUCH ENFORCEMENT IS SOUGHT IN A PROCEEDING IN
EQUITY OR AT LAW OR OTHERWISE).

NEW GLDD’S EXECUTION, DELIVERY AND PERFORMANCE OF THIS AGREEMENT DOES NOT AND
WILL NOT VIOLATE ITS CERTIFICATE OF FORMATION, LIMITED LIABILITY COMPANY
AGREEMENT OR OTHER ORGANIZATIONAL DOCUMENTS, ANY LAW, RULE, REGULATION, ORDER,
WRIT, JUDGMENT, DECREE OR AWARD APPLICABLE TO IT OR ANY CONTRACTUAL PROVISION TO
WHICH IT IS A PARTY OR TO WHICH IT OR ANY OF ITS PROPERTY IS SUBJECT.

NO AUTHORIZATION OR APPROVAL OR OTHER ACTION BY, AND NO NOTICE TO OR FILING OR
REGISTRATION WITH, ANY GOVERNMENTAL AUTHORITY OR REGULATORY BODY (OTHER THAN
THOSE WHICH HAVE BEEN OBTAINED AND ARE IN FORCE AND EFFECT) IS REQUIRED IN
CONNECTION WITH THE EXECUTION, DELIVERY AND PERFORMANCE BY NEW GLDD OF THIS
AGREEMENT AND ALL AGREEMENTS, DOCUMENTS AND INSTRUMENTS EXECUTED AND DELIVERED
PURSUANT TO THIS AGREEMENT.

NO EVENT OF DEFAULT OR DEFAULT EXISTS UNDER THE CREDIT AGREEMENT OR WOULD EXIST
AFTER GIVING EFFECT TO THIS AGREEMENT.

MISCELLANEOUS.  THE PARTIES HERETO HEREBY FURTHER AGREE AS FOLLOWS:

PAYMENT OF COSTS.  NEW GLDD HEREBY AGREES TO PAY ALL REASONABLE OUT-OF-POCKET
COSTS AND EXPENSES (EVIDENCED BY INVOICES IN REASONABLE DETAIL) INCURRED BY THE
LENDER (INCLUDING THE REASONABLE FEES AND EXPENSES OF ITS COUNSEL) IN CONNECTION
WITH THE PREPARATION, EXECUTION AND DELIVERY OF THIS AGREEMENT.

COUNTERPARTS.  THIS AGREEMENT MAY BE EXECUTED IN ONE OR MORE COUNTERPARTS, EACH
OF WHICH, WHEN EXECUTED AND DELIVERED, SHALL BE DEEMED TO BE AN ORIGINAL AND ALL
OF WHICH COUNTERPARTS, TAKEN TOGETHER, SHALL CONSTITUTE BUT ONE AND THE SAME
DOCUMENT WITH THE SAME FORCE

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AND EFFECT AS IF THE SIGNATURES OF ALL OF THE PARTIES WERE ON A SINGLE
COUNTERPART, AND IT SHALL NOT BE NECESSARY IN MAKING PROOF OF THIS AGREEMENT TO
PRODUCE MORE THAN ONE (1) SUCH COUNTERPART.

HEADINGS.  HEADINGS USED IN THIS AGREEMENT ARE FOR CONVENIENCE OF REFERENCE ONLY
AND SHALL NOT AFFECT THE CONSTRUCTION OF THIS AGREEMENT.

INTEGRATION.  THIS AGREEMENT, THE OTHER AGREEMENTS AND DOCUMENTS EXECUTED AND
DELIVERED PURSUANT TO THIS AGREEMENT, THE CREDIT AGREEMENT AND THE OTHER LOAN
DOCUMENTS CONSTITUTE THE ENTIRE AGREEMENT AMONG THE PARTIES HERETO WITH RESPECT
TO THE SUBJECT MATTER HEREOF.

GOVERNING LAW.  THIS AGREEMENT SHALL BE DEEMED TO BE A CONTRACT MADE UNDER THE
LAWS OF THE STATE OF NEW YORK, AND FOR ALL PURPOSES SHALL BE CONSTRUED IN
ACCORDANCE WITH THE LAWS AND DECISIONS OF SAID STATE, INCLUDING SECTIONS 5-1401
AND 5-1402 OF THE NEW YORK GENERAL OBLIGATIONS LAW BUT EXCLUDING ALL OTHER
CHOICE OF LAW AND CONFLICTS OF LAWS RULES.

BINDING EFFECT.  THIS AGREEMENT SHALL BE BINDING UPON AND INURE TO THE BENEFIT
OF AND BE ENFORCEABLE BY NEW GLDD AND THE ADMINISTRATIVE AGENT AND THEIR 
RESPECTIVE SUCCESSORS AND ASSIGNS.  EXCEPT AS EXPRESSLY SET FORTH TO THE
CONTRARY HEREIN, THIS AGREEMENT SHALL NOT BE CONSTRUED SO AS TO CONFER ANY RIGHT
OR BENEFIT UPON ANY PERSON OTHER THAN NEW GLDD, THE LENDERS AND THE
ADMINISTRATIVE AGENT AND THEIR RESPECTIVE SUCCESSORS AND PERMITTED ASSIGNS.

[signature pages follow]

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
by their respective officers thereunto duly authorized, as of the date first
written above.

GREAT LAKES DREDGE & DOCK
CORPORATION (f/k/a Great Lakes Dredge &
Dock Holdings Corp.)

 

 

 

 

 

By:

/s/ Deborah A. Wensel

 

Name:

Deborah A. Wensel

 

Title:

Senior Vice President, Chief Financial

 

 

Officer and Treasurer

 

 

 

 

 

 

 

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

 

 

 

 

 

By:

/s/ Charlene Wright-Jones

 

Name:

Charlene Wright-Jones

 

Title:

Assistant Vice President

 

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