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                             AMENDMENT NO. 6 TO THE
                  SECOND AMENDED AND RESTATED CREDIT AGREEMENT


                                                  Dated as of September 30, 1998

         AMENDMENT  NO. 6 TO THE SECOND  AMENDED AND RESTATED  CREDIT  AGREEMENT
(this "AMENDMENT") is entered into by WHEELING-PITTSBURGH  STEEL CORPORATION,  a
Delaware  corporation (the "BORROWER"),  the banks,  financial  institutions and
other  institutional  lenders parties to the Credit Agreement  referred to below
(collectively, the "LENDERS") and CITIBANK, N.A., as agent (the "AGENT").

         PRELIMINARY STATEMENTS:

         (1) The Borrower, the Lenders, Agent and Issuing Bank have entered into
a Second Amended and Restated Credit Agreement dated as of December 28, 1995 (as
amended, supplemented or otherwise modified through the date hereof, the "CREDIT
AGREEMENT").  Capitalized terms not otherwise defined in this Amendment have the
meanings specified in the Credit Agreement.

         (2) The Borrower  anticipates that Unimast will receive  financing on a
stand-alone  basis and will  pledge its  assets to secure  such  financing  (the
"UNIMAST FINANCING").

         (3) The  Borrower  has  requested  that the  Lenders  agree to  release
Unimast as a Guarantor  under the Guaranty and as a Grantor  under the Guarantor
Security Agreement upon the consummation of the Unimast Financing.

         (4)  The  Lenders  have  agreed  to  amend  the  Credit   Agreement  as
hereinafter set forth.

         SECTION 1.  AMENDMENTS TO CREDIT  AGREEMENT.  The Credit  Agreement is,
effective  as of  the  date  hereof  and  subject  to  the  satisfaction  of the
conditions  precedent set forth in Section 4(a), (b) and (c),  hereby amended as
follows:

         (a) The definition of "Guarantor" in Section 1.1 is amended by deleting
    the phrase "PCC, Wheeling Construction or Unimast" and substituting therefor
    the phrase "PCC or Wheeling Construction".

         (b) The definition of "Unimast" in Section 1.1 is deleted in full.



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         (c) The  definition  of "Adjusted  EBITDA" in Section 1.1 is amended in
    full to read as follows:

             "ADJUSTED EBITDA" means, for any person for any period,  the EBITDA
             for such  person  PLUS,  to the extent  included  as expense in the
             calculation   of   EBITDA,   the   pension   and  other  long  term
             post-retirement/employment  benefit charges ("Employee  Expenses");
             minus cash payments for such Employee Expenses.

         (d)  Section 5.1 is amended by deleting  the amounts set  opposite  the
     following  dates and  substituting  therefor  the  amount  set forth  below
     opposite each such date:

         September 30, 1998                      178,800,000
         December 31, 1998                       174,300,000

         March 31, 1999                          176,800,000
         June 30, 1999                           184,900,000

         (e)  Section 5.2 is amended by deleting  the amounts set  opposite  the
     following  dates and  substituting  therefor  the  amount  set forth  below
     apposite each such date:

         September 30, 1998                      7.29:1.00
         December 31, 1998                       7.82:1.00

         March 31, 1999                          8.00:1.00
         June 30, 1999                           7.66:1.00

         (f)  Section  5.3 is amended by deleting  the ratios set  opposite  the
     following dates and substituting therefor the word or ratio set forth below
     opposite each such date:

         September 30, 1998                      N/A
         December 31, 1998                       N/A

         March 31, 1999                          0.61:1.00
         June 30, 1999                           0.75:1.00



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         (g)  Section 5.4 is amended by deleting  the amounts set  opposite  the
     following  dates and  substituting  therefor  the  amount  set forth  below
     apposite each such date:

         September 30, 1998                      (130,000,000)
         October 31, 1998                        (130,100,000)
         November 30, 1998                       (130,000,000)
         December 31, 1998                       (130,000,000)

         January 31, 1999                        (135,000,000)
         February 28, 1999                       (135,000,000)
         March 31, 1999                          (140,000,000)
         April 30, 1999                          (140,000,000)
         May 31, 1999                            (140,000,000)
         June 30, 1999                           (140,000,000)
              and thereafter

         (h)  Section 5.5 is amended by deleting  the amounts set  opposite  the
     following  dates and  substituting  therefor  the  amount  set forth  below
     apposite each such date:

         September 30, 1998                      127,300,000
         December 31, 1998                       140,700,000

         March 31, 1999                          151,200,000
         June 30, 1999                           169,500,000
              and thereafter

         (i) Section 8.1(k) is deleted in full and inserted in its place is "(k)
     [Intentionally deleted]".

         SECTION 2.  WAIVER.  Effective as of the date hereof and subject to the
satisfaction of the conditions  precedent set forth in Section 4(a) and (b), the
Lenders,  notwithstanding  anything in the contrary  contained in Section 7.5 of
the Credit  Agreement,  hereby consent to the merger of Champion Metal Products,
Inc. into Wheeling Construction Products, Inc. and subsequent merger of Wheeling
Construction Products, Inc. into Borrower.

         SECTION 3.  RELEASE.  (a)  Effective as of the date of the Unimast Loan
Agreement and subject to the satisfaction of the conditions  precedent set forth
in Section 4, the Lenders  hereby (i) release  Unimast as a Guarantor  under the
Guaranty,  (ii)  release  Unimast  as a  Grantor  under the  Guarantor  Security
Agreement and the assets of Unimast from the security


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interests  granted  thereby  and  (iii)  release  the  pledge  of the  Guarantor
Intercompany Note of Unimast from the Borrower Pledge Agreement.

         (b) The Agent agrees that it will, at the Borrower's expense,  and upon
the release of the  Collateral  specified  in  paragraph  (a) of this Section 3,
execute  and  deliver to the  Borrower  such  documents  as the  Borrower  shall
reasonably  request to evidence the release of such item of Collateral  from the
assignment and security interest granted under the Guarantor  Security Agreement
and Borrower Pledge Agreement, as applicable.

         SECTION 4.  CONDITIONS OF  EFFECTIVENESS.  This Amendment  shall become
effective as of the date first above written on the Business Day when,  and only
when, the following conditions shall have been satisfied:

         (a) The  Agent  shall  have  received  counterparts  of this  Amendment
     executed by the  Borrower,  each other Loan Party and all of Lenders or, as
     to any of the Lenders,  advice  satisfactory to the Agent that such Lenders
     have executed this Amendment;

         (b) The  Agent  shall  have  received  a  certificate  signed by a duly
     authorized officer of the Borrower stating that:

             (i) The  representations  and  warranties  contained  in the Credit
         Agreement  and each Loan  Document are correct on and as of the date of
         such certificate as though made on and as of the date hereof other than
         any such representations or warranties that, by their terms, refer to a
         date other than the date of such certificate; and

             (ii) No event has occurred and is  continuing  that  constitutes  a
         Default or an Event of Default.

         (c) The Unimast Financing shall have been consummated.

The  effectiveness  of this  Amendment is  conditioned  upon the accuracy of the
factual matters described herein. This Amendment is subject to the provisions of
Section 10.1 of the Credit Agreement.

         SECTION 5.  REFERENCE TO AND EFFECT ON THE LOAN  DOCUMENTS.  (a) On and
after  the  effectiveness  of  this  Amendment,  each  reference  in the  Credit
Agreement  to "this  Agreement",  "hereunder",  "hereof" or words of like import
referring  to the  Credit  Agreement,  and  each  reference  in each of the Loan
Documents to "the Credit  Agreement",  "thereunder",  "thereof" or words of like
import  referring to the Credit  Agreement  shall mean and be a reference to the
Credit Agreement, as amended by this Amendment.

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         (b)  The  Credit   Agreement  and  each  of  the  Loan  Documents,   as
specifically  amended by this  Amendment,  are and shall  continue to be in full
force and effect and are hereby in all respects ratified and confirmed.

         (c) The execution,  delivery and  effectiveness of this Amendment shall
not,  except as  expressly  provided  herein,  operate as a waiver of any right,
power or remedy of any Lender,  the Agent,  or the Issuing Bank under the Credit
Agreement or any Loan Document,  nor constitute a waiver of any provision of the
Credit Agreement or any Loan Document.

         SECTION 6. COSTS AND EXPENSES. The Borrower agrees to pay on demand all
costs and expenses of the Agent in connection with the  preparation,  execution,
delivery and  administration,  modification  and amendment of this Amendment and
the other  instruments  and  documents  to be  delivered  hereunder  (including,
without  limitation,  the reasonable fees and expenses of counsel for the Agent)
in accordance with the terms of Section 10.4(a) of the Credit Agreement.

         SECTION 7. EXECUTION IN COUNTERPARTS. This Amendment may be executed in
any  number  of  counterparts  and  by  different  parties  hereto  in  separate
counterparts,  each of which when so executed  shall be deemed to be an original
and all of which taken together shall constitute but one and the same agreement.
Delivery of an executed  counterpart  of a signature  page to this  Amendment by
telecopier shall be effective as delivery of a manually executed  counterpart of
this Amendment.

         SECTION 8.  GOVERNING  LAW.  This  Amendment  shall be governed by, and
construed in accordance with, the laws of the State of New York.


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

                                 BORROWER

                                       WHEELING-PITTSBURGH STEEL
                                       CORPORATION


                                       By: /s/ Paul J. Mooney
                                           ----------------------------
                                       Name:   Paul J. Mooney
                                       Title:  Executive Vice President


                                 AGENT

                                       CITIBANK, N.A., as Agent


                                       By: /s/ illegible
                                           ----------------------------
                                       Name:
                                       Title:


                                 LENDERS

                                       CITICORP USA, INC.


                                       By: /s/ illegible
                                           ----------------------------
                                          Name:
                                          Title:


                                       CORESTATES BANK, N.A.


                                        By:   /s/ Myron Landau
                                            ---------------------------
                                           Name:   Myron Landau
                                           Title:  Vice President


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                                   BANKAMERICA BUSINESS CREDIT, INC.


                                   By: /s/ Walter T. Shellman
                                       --------------------------------
                                       Name:   Walter T. Shellman
                                       Title:  Vice President


                                   STAR BANK, N.A.


                                   By: /s/ Mike Elbert
                                       --------------------------------
                                       Name:   Mike Elbert
                                       Title:  Vice President


                                   NATIONSBANK, N.A.


                                   By: /s/ Melba B. Orzon
                                       --------------------------------
                                       Name:   Melba B. Orzon
                                       Title:  Vice President


                                   NATIONAL CITY COMMERCIAL
                                    FINANCE, INC.


                                   By: /s/ John P. Dunn
                                       --------------------------------
                                       Name:   John P. Dunn
                                       Title:  Vice President


                                   CONSENTED TO AND ACKNOWLEDGED:

                                   WHEELING-PITTSBURGH CORPORATION


                                   By: /s/ Paul J. Mooney
                                       --------------------------------
                                       Name:  Paul J. Mooney
                                       Title: Executive Vice President



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                                   WHEELING CONSTRUCTION PRODUCTS,
                                   INC.


                                   By: /s/ Paul J. Mooney
                                       ----------------------------------
                                       Name:   Paul J. Mooney
                                       Title:  Vice President & Treasurer


                                   PITTSBURGH-CANFIELD CORPORATION


                                   By: /s/ Paul J. Mooney
                                       ----------------------------------
                                       Name:   Paul J. Mooney
                                       Title:  Vice President & Treasurer


                                   UNIMAST INCORPORATED


                                   By: /s/ John W. Testa
                                       --------------------------------
                                       Name:   John W. Testa
                                       Title:  Secretary


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