EXHIBIT 99.1


                                 CERTIFICATIONS

I, Joe E. Corvin, certify that:

1.       I have reviewed this annual report on Form 10-K of Oregon Steel Mills,
         Inc.;

2.       Based on my knowledge, this annual report does not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         to make the statements made, in light of the circumstances under which
         such statements were made, not misleading with respect to the period
         covered by this annual report;

3.       Based on my knowledge, the financial statements, and other financial
         information included in this annual report, fairly present in all
         material respects the financial condition, results of operations and
         cash flows of the registrant as of, and for, the periods presented in
         this annual report;

4.       The registrant's other certifying officer and I are responsible for
         establishing and maintaining disclosure controls and procedures (as
         defined in Exchange Act Rules 13a-14 and 15d-14) for the registrant and
         we have:

a)       designed such disclosure controls and procedures to ensure that
         material information relating to the registrant, including its
         consolidated subsidiaries, is made known to us by others within those
         entities, particularly during the period in which this annual report is
         being prepared;
b)       evaluated the effectiveness of the registrant's disclosure controls and
         procedures as of a date within 90 days prior to the filing date of this
         annual report (the "Evaluation Date"); and
c)       presented in this annual report our conclusions about the effectiveness
         of the disclosure controls and procedures based on our evaluation as of
         the Evaluation Date;

5.       The registrant's other certifying officer and I have disclosed, based
         on our most recent evaluation, to the registrant's auditors and the
         audit committee of registrant's board of directors (or persons
         performing the equivalent function):

         a)   all significant deficiencies in the design or operation of
              internal controls which could adversely affect the registrant's
              ability to record, process, summarize and report financial data
              and have identified for the registrant's auditors any material
              weaknesses in internal controls; and
         b)   any fraud, whether or not material, that involves management or
              other employees who have a significant role in the registrant's
              internal controls; and

6.       The registrant's other certifying officer and I have indicated in this
         annual report whether or not there were significant changes in internal
         controls or in other factors that could significantly affect internal
         controls subsequent to the date of our most recent evaluation,
         including any corrective actions with regard to significant
         deficiencies and material weaknesses.


    Date:   March 17, 2003                           /s/ Joe E. Corvin
                                         ---------------------------------------
                                                       Joe E. Corvin
                                          President and Chief Executive Officer