EXHIBIT 9


                             AMENDMENT TO AGREEMENT
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         This Amendment is made by and between Pitt-Des Moines, Inc. (the
"Company") and W. W. McKee (the "Employee") as of the date last written below.

         WHEREAS, the Company and the Employee entered into that certain
agreement dated January 24, 1991 (the "Agreement"), which was amended when the
Company declared stock splits effective March 28, 1997 and June 26, 1998 as to
shares subject to such Agreement;

         WHEREAS, the Employee's employment with the Company will be terminated
in connection with the consummation of the proposed sale of all the issued and
outstanding shares of the Company's stock; and

         WHEREAS, the Board of Directors of the Company has authorized certain
modifications to the Agreement to compensate the Employee for his valuable
services and to limit certain non-competition restrictions which are no longer
required to protect the interests of the Company.

         NOW, THEREFORE, intending to be legally bound, the parties agree as
follows:

         1. The definition of "Change of Control" contained in Section 1 of the
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Agreement is hereby amended by removing the word "or" from the end of
subparagraph (iv), removing the "." at the end of subparagraph (v) and adding ";
or" to the end thereof, and by adding the following subparagraph (vi) to the end
of thereof:

         "(vi) the sale by the Company of its Steel Service Centers division to
Reliance Steel and Aluminum Co. effective July 2, 2001."

         2. The definition of "Sale of the Company" is amended and restated in
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its entirety to read as follows:

         "Sale of the Company shall mean a Change of Control described in
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subparagraphs (iii), (iv) or (vi) of the definition of Change of Control or the
acquisition by any person of more than 50% of the Voting Securities pursuant to
a tender offer or exchange offer made to the shareholders of the Company."

         3. Section 2 of the Agreement is hereby amended by adding the following
provision to the end thereof:

         "Notwithstanding any other provision of this Agreement to the contrary,
the Employee's employment shall be terminated effective immediately following
the consummation of a sale, merger, consolidation, or other exchange or transfer
involving all of the issued and outstanding securities of the Company."



         4. Section 6 of the Agreement is hereby amended by adding the following
provisions to the end thereof:

         "6.06 Sale. Notwithstanding the foregoing provisions of Section 6 of
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this Agreement to the contrary, if the Employee's employment is terminated
during the Employment Period for any reason other than termination by the
Company for Cause or by the Employee for other than Good Reason, including, but
not limited to, such reasons as involuntary termination, death, disability,
application of the last sentence of Section 2, or voluntary termination for Good
Reason, or if after notice is given pursuant to Section 5.05 the Employee's
employment with the Company is not continued for any reason upon expiration of
the Employment Period (at the behest of the Company or the Employee, or both),
the Employee shall be entitled to all Accrued Obligations due to the Employee at
the Date of Termination, plus an amount equal to three times the total base
salary and cash bonus paid or payable to the Employee by the Company in the last
full fiscal year of the Company prior to the Effective Date. Such benefit and
any Accrued Obligations shall be paid to the Employee or the Employee's estate
or beneficiary, as applicable, in a lump sum cash payment upon the earlier of
(i) consummation of a sale, merger, consolidation, or other exchange or transfer
involving all of the issued and outstanding securities of the Company, or (ii)
the 30th day following the Date of Termination. Upon payment of such benefit and
Accrued Obligations, all of the Company's obligation arising under Section 6 of
the agreement shall be deemed satisfied."

         5. Section 7.01 of the Agreement is hereby amended by deleting the "."
at the end of the first paragraph and adding the following provision to the end
thereof:

         "; provided, however, in the event of a Sale within the meaning of
subparagraph (vi) of the definition of a Change of Control, the lump sum cash
payment due under this Section 7.01 shall be paid upon the earlier of (i)
consummation of sale, merger, consolidation, or other exchange or transfer
involving all of the issued and outstanding securities of the Company, or (ii)
the 30th day following the one-year anniversary of such Sale; and provided
further, in the event of a Sale within the meaning of subparagraph (vi) of the
definition of a Change of Control, the value of the lump sum cash payment due
under this Section 7.01 shall be calculated based on (i) the total consideration
paid or payable to the Company or the stockholders of the Company as provided
for in the definitive agreement utilized to consummate the sale, merger,
consolidation, or other exchange or transfer involving all of the issued and
outstanding securities of the Company, or (ii) if any such transaction is not
consummated within one-year of such Sale, the fair market value of the Company
on July 2, 2001 determined based on the closing price of the Company's common
stock on July 2, 2001."

         6. Section 7.02 of the Agreement is hereby amended by deleting the "."
at the end thereof and adding the following provision to the end thereof:

         "; provided, further, solely for purposes of this Section 7.02, a Sale
of the Company shall not include a Change of Control described in subparagraph
(vi) of the definition of Change of Control."

         7. Section 11 of the Agreement is hereby amended by deleting all of the
provisions thereof and restated to read as follows:



         "SECTION 11.   CERTAIN ADDITIONAL PAYMENTS BY THE COMPANY.
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                  (a) Notwithstanding anything in this Agreement to the
contrary, in the event it shall be determined that any payment or distribution
made, or benefit provided, by the Company to or for the benefit of the Employee
(whether paid or payable or distributed or distributable pursuant to the terms
of this Agreement or otherwise, but determined without regard to any additional
payments required under this Section 11) (hereinafter a "Payment") would be
subject to the excise tax imposed under Section 4999 of the Code (or any similar
excise tax) or any interest or penalties are incurred by the Employee with
respect to such excise tax (such excise tax, together with any such interest and
penalties, are hereinafter collectively referred to as the "Excise Tax"), then
the Employee shall be entitled to receive an additional payment (a "Gross-Up
Payment") in an amount such that after payment by the Employee of all taxes
(including any Excise Tax) imposed upon the Gross-Up Payment and any interest
and penalties imposed with respect to such taxes, the Employee retains from the
Gross-Up Payment an amount equal to the Excise Tax imposed upon the Payments.

                  (b) All determinations required to be made under this Section
11, including determination of whether a Gross-Up Payment is required and of the
amount of any such Gross-Up payment, shall be made by an accounting firm of
nationally recognized standing, and may include the audit firm for the Company
(the "Accounting Firm"), which shall provide detailed supporting calculations
both to the Company and the Employee prior to the closing for the sale of all
the issued and outstanding securities of the Company. The Gross-Up Payment, if
any, shall be paid to the Employee upon consummation of the sale of all the
issued and outstanding securities of the Company. Any determination by the
Accounting Firm meeting the requirements of this Section 11 shall be binding
upon the Company and the Employee."

         8. Section 13 of the Agreement is hereby amended by deleting all of the
provisions thereof and restated to read as follows:

         "SECTION 13.   RESERVED."
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         This Amendment may be executed in one or more counterparts, each of
which when taken together shall be considered one and the same.

         IN WITNESS WHEREOF, the undersigned have executed this Amendment the
26th day of June, 2001.

                                    PITT-DES MOINES, INC.

                                      /s/ R.A. Byers
                                    -----------------------------------
                                    By: R.A. Byers,
                                    Vice President, Finance


                                     /s/ W.W. McKee
                                    -----------------------------------
                                    W. W. McKee