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                                                                    Exhibit 31.1

                                 CERTIFICATION

I, Richard J. Pershing, certify that:

     1. I have reviewed this annual report on Form 10-K, as amended, of Mirant
Americas Generation, LLC;

     2. Based on my knowledge, this amended 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
amended annual report;

     3. Based on my knowledge, the financial statements, and other financial
information included in this amended 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 amended annual
report;

     4. The registrant's other certifying officers 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 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 amended 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 amended annual report (the "Evaluation Date"); and

          (c) presented in this amended 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 officers 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 functions):

          (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 officers and I have indicated in this
amended annual report whether 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.

                                          By:    /s/ RICHARD J. PERSHING
                                            ------------------------------------
                                                    Richard J. Pershing
                                               President and Chief Executive
                                                           Officer
                                               (Principal Executive Officer)

Date: August 27, 2003