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Exhibit 10.21

[ORANGE COUNTY BUSINESS BANK LOGO]

June 19, 2006

Roy L. Gill, Vice President
The Willdan Group of Companies
2401 East Katella Avenue, Suite #300
Anaheim, CA 92660

Re:    Borrower: The Willdan Group of Companies, a California Corporation

Dear Mr. Gill:

        In response to your letter dated March 29, 2006, Orange County Business Bank has approved the following amendments to the loan documents that pertain to Loan #10174420 and Loan #10274428.

        In addition, in response to your letter dated June 8, 2006, Orange County Business Bank has approved the company's "zero value" stock dividend/stock split which was instituted on January 1, 2005 and completed on March 30, 2006. Please let us know if you have any questions. Thank you.

Sincerely,    

/s/  
NIC GOERES      
Nic Goeres
Vice President
Senior Relationship Manager
(949) 999-2643

 

/s/  
CHUCK TULLOH      
Chuck Tulloh
Executive Vice President
Chief Credit Officer
(949) 999-3556



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