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                                 FORM 51-102F3

                             MATERIAL CHANGE REPORT

ITEM 1   NAME AND ADDRESS OF COMPANY

         Gerdau Ameristeel Corporation
         Hopkins Street South
         Whitby, Ontario
         L1N 5T1

ITEM 2   DATE OF MATERIAL CHANGE

         September 9, 2004

ITEM 3   NEWS RELEASE

         A press release was issued on September 9, 2004 and is attached as
         Schedule "A".

ITEM 4   SUMMARY OF MATERIAL CHANGE

         Gerdau Ameristeel Corporation ("Gerdau Ameristeel") announced on
         September 9, 2004 that its U.S. operating subsidiary, Gerdau
         Ameristeel US Inc., has entered into definitive agreements with
         Cargill, Incorporated and certain of its subsidiaries to purchase the
         fixed assets and working capital of four long steel product minimills,
         three wire processing facilities, and a grinding ball facility. The
         purchase price for the acquired assets is $266 million in cash,
         subject to adjustment for working capital fluctuations prior to the
         closing date.

ITEM 5   FULL DESCRIPTION OF MATERIAL CHANGE

         Gerdau Ameristeel announced on September 9, 2004 that its U.S.
         operating subsidiary, Gerdau Ameristeel US Inc., has entered into
         definitive agreements with Cargill, Incorporated and certain of its
         subsidiaries to purchase the fixed assets and working capital of four
         long steel product minimills, three wire processing facilities, and a
         grinding ball facility. The purchase price for the acquired assets is
         $266 million in cash, subject to adjustment for working capital
         fluctuations prior to the closing date.

         The agreement includes the assumption by Gerdau Ameristeel at the
         closing of substantially all of the liabilities of the businesses
         being acquired, including specific contractual obligations and
         selected employee liabilities. Gerdau Ameristeel has available cash
         and existing credit facilities that are sufficient to finance the
         transaction. Subject to satisfactory completion of anti-trust and
         other regulatory review, the transaction is expected to close before
         the end of 2004.

ITEM 6   RELIANCE ON SUBSECTION 7.1(2) OR (3) OF NATIONAL INSTRUMENT 51-102

         Not applicable


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ITEM 7   OMITTED INFORMATION

         No significant facts remain confidential in, and no information has
         been omitted from, this report.

ITEM 8   EXECUTIVE OFFICER

         For further information, please contact Tom J. Landa, Vice-President,
         Finance, Chief Financial Officer and Secretary at (813) 207-2300.

ITEM 9   DATE OF REPORT

         September 14, 2004




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                                  SCHEDULE "A"


                            [GERDAU AMERISTEEL LOGO]


GERDAU AMERISTEEL ANNOUNCES AGREEMENTS TO ACQUIRE NORTH STAR STEEL ASSETS

Toronto, ON, September 9, 2004 - Gerdau Ameristeel Corporation (TSX: GNA.TO)
today announced that its U.S. operating subsidiary, Gerdau Ameristeel US Inc.,
has entered into definitive agreements with Cargill, Incorporated and certain of
its subsidiaries to purchase the fixed assets and working capital of four long
steel product minimills in St. Paul, Minnesota; Wilton, Iowa; Calvert City,
Kentucky; and Beaumont, Texas; three wire rod processing facilities in Beaumont,
Texas; Carrollton, Texas; and Memphis, Tennessee; and a grinding ball facility
in Duluth, Minnesota. The integration of these operations will provide Gerdau
Ameristeel's customers with expanded geographical coverage and a broader range
of products.

The purchase price for the acquired assets is $266 million in cash subject to
adjustment for working capital fluctuations prior to the closing date. The
agreement includes the assumption by Gerdau Ameristeel at the closing of
substantially all of the liabilities of the businesses being acquired, including
specific contractual obligations and selected employee liabilities. Gerdau
Ameristeel has available cash and existing credit facilities that are sufficient
to finance the transaction. Subject to satisfactory completion of anti-trust and
other regulatory reviews, the transaction is expected to close before the end of
2004.

The four North Star Steel minimills have an annual production capacity of
approximately two million tons of long steel products, principally merchant
bars, special bar quality steel, light structural shapes, reinforcing bar and
wire rod. Customers include steel service centers, original equipment
manufacturers and steel fabricators. The four downstream product manufacturing
facilities have an annual production capacity of approximately 300,000 tons. The
wire rod processing facilities produce reinforcing wire mesh, chain link fencing
and industrial wire. The grinding ball facility produces grinding balls for
crushing and processing of minerals in various mining industries.

Phillip Casey, president and CEO of Gerdau Ameristeel commented: "This
transaction combines the professional talents and solid reputations of two
exceptional organizations. The consolidation of the North Star team with Gerdau
Ameristeel is a dynamic step in the continuing revitalization of the North
American steel industry. This combination will provide new opportunities for the
employees, customers and associated stakeholders of both companies."

ABOUT GERDAU AMERISTEEL

Gerdau Ameristeel is the second largest minimill steel producer in North America
with annual manufacturing capacity of over 6.4 million tons of mill finished
steel product. Through its vertically integrated network of 11 minimills
(including one 50% owned minimill), 13 scrap recycling facilities and 32
downstream operations, Gerdau Ameristeel primarily serves customers in the
eastern half of North America. The company's products are generally sold to
steel service centers, steel fabricators, or directly to original equipment
manufacturers for use in



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a variety of industries, including construction, automotive, mining and
equipment manufacturing. The common shares of Gerdau Ameristeel are traded on
the Toronto Stock Exchange under the symbol GNA.TO. For additional financial and
investor information, visit www.gerdauameristeel.com.

FOR MORE INFORMATION PLEASE CONTACT:

Tom J. Landa
Vice President and Chief Financial Officer
Gerdau Ameristeel
(813) 207-2300
tlanda@gerdauameristeel.com

David Feider
Director of Media Relations
Cargill
(952) 742-6910
david_feider@cargill.com