EXHIBIT 31.2

# CERTIFICATION

I, Nancy J. McGurk, certify that:

|1. |  | I have reviewed this quarterly report on Form 10-QSB for the nine months ended
               September 30, 2004 of Atlas America Public #122003 Limited Partnership.
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|2. |  | Based on my knowledge, this 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 report;
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|3. |  | Based on my knowledge, the financial statements, and other financial information
               included in this 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 report;
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|4. |  | The registrants other certifying officer(s) and I are responsible for
               establishing and maintaining disclosure controls and procedures (as defined in
               Exchange Act Rules 13a-14 and 15d-14) [Omission in accordance with SEC
               Release Nos. 33-8238, 34-47986 and IC-26068 (September 5, 2003)] for the registrant
               and have:
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|a) |  | Designed such disclosure
              controls and procedures, or caused such disclosure
              controls and procedures to be designed under our supervision, 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 report is being prepared;
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|b) |  | [Omitted in accordance
              with SEC Release Nos. 33-8238, 34-47986 and IC-26068 (September 5, 2003)];
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|c) |  | Evaluated the effectiveness
              of the registrant's disclosure controls and procedures and presented in this report our conclusions
              about the effectiveness of the disclosure controls and procedures as of the end of the period
              covered by this report based on such evaluation; and
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|d) |  | Disclosed in this report
          any change in the registrants internal control
          over financial reporting that occurred during the registrants most recent
          fiscal quarter (the registrants fourth fiscal quarter in the case of an
          annual report) that has materially affected, or is reasonably likely to
          materially affect, the registrants internal control over financial
          reporting; and
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|5. |  | The registrants
               other certifying officer(s) and I have disclosed, based on
               our most recent evaluation of internal control over financial reporting, to the
               registrants auditors and the audit committee of the registrants
               board of directors (or persons performing the equivalent functions):
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|a) |  | All significant
          deficiencies and material weaknesses in the design or operation
          of internal control over financial reporting which are reasonably likely to
          adversely affect the registrants ability to record, process, summarize and
          report financial information; and
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|b) |  | Any fraud, whether or
          not material, that involves management or other employees
          who have a significant role in the registrants internal control over
          financial reporting.
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| | By: | /s/Nancy J. McGurk
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| | Name: | Nancy J. McGurk
| | ----- | ---------------

| | Title: | Chief Financial
              Officer of the Managing General Partner
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| | Date: | November 15, 2004
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