EXHIBIT 31.2

                                  Certification



I, Richard H. Marsh, certify that:

1.   I have reviewed this amended annual report on Form 10-K/A of FirstEnergy
     Corp.;

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 the 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:  September 11, 2003
                                          /s/Richard H. Marsh
                                       ---------------------------
                                             Richard H. Marsh
                                         Chief Financial Officer


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