Document:

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                                                              Exhibit 10.1c(1)

                     FIRST AMENDMENT TO CREDIT AGREEMENT

           THIS FIRST AMENDMENT TO CREDIT AGREEMENT (this "Amendment"), dated
as of March 15, 2001, by and among STEEL DYNAMICS, INC., an Indiana
corporation (the "Borrower"), the lenders listed on the signature pages hereof
and MELLON BANK, N.A., a national banking association, as agent for the
Lenders under the Credit Agreement referred to below (the "Agent").

                                  RECITALS:

           WHEREAS the Borrower, certain lenders, the Agent, and certain
Arrangers entered into a Credit Agreement, dated as of May 5, 2000 (the
"Original Agreement"), pursuant to which the Lenders have agreed to extend
credit to the Borrower;

           WHEREAS, the Borrower and the Required Lenders (as defined in the
Original Agreement) desire to amend the Original Agreement to make certain
changes therein;

           WHEREAS, capitalized terms not otherwise defined herein shall have
the meanings assigned thereto in the Original Agreement.

           NOW, THEREFORE, the parties hereto, in consideration of their
mutual covenants and agreements hereinafter set forth and intending to be
legally bound hereby agree as follows:

           Section 1. Amendment. Section 6.04 of the Original Agreement is
hereby amended by deleting the period at the end of paragraph (f) thereof, by
inserting a semicolon in lieu of such period and adding, at the end of Section
6.04, a new paragraph (g) to read as follows:

                               (g) the guaranty by the Borrower of not more
                    than $8,250,000 principal amount of Indebtedness of IDI
                    owing to lenders under the Credit Agreement, dated as of
                    December 31, 1997, as amended from time to time, among
                    IDI, certain Lenders and Mellon Bank, N. A., as Issuing
                    Bank and Agent.

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           Section 2.  Directions to Agent.  By execution of this Amendment,
the Required Lenders hereby direct the Agent to execute and deliver this
Amendment.

           Section 3.  Miscellaneous.  (a) This Amendment shall become
effective upon execution and delivery hereof by the Required Lenders, the
Borrower and the Agent

           (b) The Original Agreement, as amended by this Amendment, is in all
respects ratified, approved and confirmed and shall, as so amended, remain in
full force and effect. From and after the date hereof, all references to the
"Agreement" in the Original Agreement and in the other Loan Documents shall be
deemed to be references to the Original Agreement as amended by this
Amendment.

           (c) This Amendment shall be deemed to be a contract under the laws
of the State of New York and for all purposes shall be governed by and
construed and enforced in accordance with the laws of said State.

           (d) This Amendment may be executed in any number of counterparts
and by the different parties hereto on separate counterparts, each of which,
when so executed, shall be deemed an original, but all such counterparts shall
constitute but one and the same instrument.

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           IN WITNESS WHEREOF, the parties hereto, by their officers thereunto
duly authorized, have executed and delivered this Amendment as of the date
first above written.

                                        STEEL DYNAMICS, INC.

                                        By
                                          ----------------------------------
                                        Title:

                                        MELLON BANK, N.A., as Lender
                                          and as Agent

                                        By
                                          ----------------------------------
                                        Title:

                                        KREDITANSTALT FUR WIEDERAUFBAU

                                        By
                                          ----------------------------------
                                        Title:

                                        By
                                          ----------------------------------
                                        Title:

                                        THE HUNTINGTON NATIONAL BANK

                                        By
                                          ----------------------------------
                                        Title:<PAGE>   1

                                                              Exhibit 10.1c(2)

        CONSENT AND AGREEMENT WITH RESPECT TO EXTENSION OF COMMITMENT
      PERIOD END DATE AND TERMINATION OF COMMITMENT OF ONE LENDER UNDER
                               CREDIT AGREEMENT

           THIS CONSENT AND AGREEMENT (this "Consent"), dated as of July 10,
2001, is granted to STEEL DYNAMICS, INC., an Indiana corporation (the
"Borrower"), by the lenders listed on the signature pages hereof and MELLON
BANK, N.A., a national banking association, as agent for the Lenders under the
Credit Agreement referred to below (the "Agent").

                                  RECITALS:

           WHEREAS the Borrower, certain lenders, the Agent, and certain
Arrangers entered into a Credit Agreement, dated as of May 5, 2000 (as amended
by the First Amendment, dated as of March 15, 2001, the "Credit Agreement"),
pursuant to which the Lenders have agreed to extend credit to the Borrower;

           WHEREAS, the "Commitment Period End Date", as defined in the Credit
Agreement, is July 17, 2001; and

           WHEREAS, The Huntington National Bank desires that its Commitment
under the Credit Agreement expire on the current Commitment Period End Date
and the Borrower and the other Lenders are agreeable to such expiration; and

           WHEREAS, as contemplated by Section 2.03 of the Credit Agreement,
the Borrower has requested that the other Lenders consent to an extension of
the Commitment Period End Date and the other Lenders are willing to provide
such consent; and

           WHEREAS, capitalized terms not otherwise defined herein shall have
the meanings assigned thereto in the Original Agreement.

           NOW, THEREFORE, the parties hereto, in consideration of their
mutual covenants and agreements hereinafter set forth and intending to be
legally bound hereby agree as follows:

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           Section 1. Termination of Commitment. Upon this Consent becoming
effective as set forth below, the Commitment of The Huntington National Bank
under the Credit Agreement shall terminate on July 17, 2001, with the result
that The Huntington National Bank shall cease to be a Lender as of such date
and the aggregate Unborrowed Commitment Amounts of the Lenders from and after
such date shall be $45,000,000. On July 17, 2001, the Borrower shall pay to
the Agent, for the account of The Huntington National Bank, all accrued and
unpaid Commitment Fee attributable to the Commitment of The Huntington
National Bank.

           Section 3. Consent. As contemplated by Section 2.03 of the Credit
Agreement, the Lenders (other than The Huntington National Bank) hereby
consent to the extension of the Commitment Period End Date under the Credit
Agreement to July 16, 2002. As contemplated by the last sentence of Section
2.03 of the Credit Agreement, this Consent shall, upon execution hereof by
each of the Lenders, the Agent and the Borrower, and subject to the conditions
set forth in such sentence, become effective on July 17, 2001; provided,
however, that this Consent shall not become effective if any Loans are
outstanding under the Credit Agreement on July 17, 2001. This Consent shall
become effective as set forth in the immediately preceding sentence whether or
not the Borrower's request therefore complied with the timing requirement of
the second sentence of Section 2.03 of the Credit Agreement.

           Section 3. Certain Conditions. As contemplated by Section 4.02 of
the Credit Agreement (which is referred to in the last sentence of Section
2.03 of the Credit Agreement with respect to the effectiveness of this
Consent), the Borrower confirms that its request for this Consent and its
execution hereof shall constitute a representation and warranty that the
conditions set forth in Section 4.02 of the Credit Agreement will be satisfied
as of July 17, 2001.

           Section 4.  Miscellaneous.  (a) The Credit Agreement is in all
respects ratified, approved and confirmed and shall remain in full force and
effect among the Borrower, Mellon Bank, N. A. and Kreditanstalt fur
Wiederaufbau.

           (b) This Consent shall be deemed to be a contract under the laws of
the State of New York and for all purposes shall be governed by and construed
and enforced in accordance with the laws of said State.

           (c) This Consent may be executed in any number of counterparts and
by the different parties hereto on separate counterparts, each of which, when
so executed, shall be deemed

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an original, but all such counterparts shall constitute but one and the same
instrument.

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           IN WITNESS WHEREOF, the parties hereto, by their officers thereunto
duly authorized, have executed and delivered this Consent as of the date first
above written.

                                        STEEL DYNAMICS, INC.

                                        By
                                          -----------------------------------
                                        Title:

                                        MELLON BANK, N.A., as Lender
                                          and as Agent

                                        By
                                          -----------------------------------
                                        Title:

                                        KREDITANSTALT FUR WIEDERAUFBAU

                                        By
                                          -----------------------------------
                                        Title:

                                        By
                                          -----------------------------------
                                        Title:

                                        THE HUNTINGTON NATIONAL BANK

                                        By
                                          -----------------------------------
                                        Title:

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