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EXHIBIT 99.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER
Pursuant to 18 U.S.C. Section 1350, as adopted
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

        The undersigned, Mogens C. Bay, Chairman and Chief Executive Officer of Valmont Industries, Inc. (the "Company"), has executed this certification in connection with the filing with the Securities and Exchange Commission of the Company's Quarterly Report on Form 10-Q for the quarter ended September 28, 2002 (the "Report").

        The undersigned hereby certifies, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, to his knowledge that:

1.

the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.

the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

        IN WITNESS WHEREOF, the undersigned has executed this certification as of the 11th day of November 2002.

/s/  MOGENS C. BAY Mogens C. Bay
Chairman and Chief Executive Officer

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CERTIFICATION OF CHIEF FINANCIAL OFFICER
Pursuant to 18 U.S.C. Section 1350, as adopted
pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

        The undersigned, Terry J. McClain, Senior Vice President and Chief Financial Officer,Valmont Industries, Inc. (the "Company"), has executed this certification in connection with the filing with the Securities and Exchange Commission of the Company's Quarterly Report on Form 10-Q for the quarter ended September 28, 2002 (the "Report").

        The undersigned hereby certifies, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, to his knowledge that:

1.

the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.

the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

        IN WITNESS WHEREOF, the undersigned has executed this certification as of the 11th day of November 2002.

/s/  TERRY J. MCCLAIN Terry J. McClain
Executive Vice President and
Chief Financial Officer

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EXHIBIT 99.1