**Exhibit 31.1**

**CERTIFICATION**

I, Steven R. Williams, certify that:

1.               I have reviewed this Annual Report on Form 10-K of theRegistrant:

2.               Based on my knowledge, this report does not containany untrue statement of a material fact or omit to state a material factnecessary to make the statements made, in light of the circumstances underwhich such statements were made, not misleading with respect to the periodcovered by this report;

3.               Based on my knowledge, the financial statements, andother financial information included in this report, fairly present in allmaterial respects the financial condition, results of operations and cash flowsof the registrant as of, and for, the periods presented in this report;

4.     The registrant's other certifying officer and Iare responsible for establishing and maintaining disclosure controls andprocedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for theregistrant and have:

a.       Designed such disclosure controlsand procedures, or caused such disclosure controls and procedures to bedesigned under our supervision, to ensure that material information relating tothe registrant is made known to us by others within those entities,particularly during the period in which this report is being prepared;

b.     Evaluated the effectiveness of the registrant'sdisclosure controls and procedures and presented in this report our conclusionsabout the effectiveness of the disclosure controls and procedures, as of theend of the period covered by this report based on such evaluation; and

c.               Disclosed in this report any change in theregistrant's internal control over financial reporting that occurred during theregistrant's most recent fiscal quarter (the registrant's fourth fiscal quarterin the case of an annual report) that has materially affected, or is reasonablylikely to materially affect, the registrant's internal control over financialreporting; and

5.               The registrant's other certifying officer and I havedisclosed, based on our most recent evaluation of internal control overfinancial reporting, to the registrant's auditor and the audit committee of theregistrant's board of directors (or persons performing the equivalentfunctions);

a.               All significant deficiencies and material weaknessesin the design or operation of internal control over financial reporting whichare reasonably likely to adversely affect the registrant's ability to record,process, summarize and report financial information; and

b.              Any fraud, whether or not material, that involvesmanagement or other employees who have a significant role in the registrant'sinternal control over financial reporting.

Date: December 21, 2006

|  | /s/ Steven R. Williams                                                                                |  |
|--|-------------------------------------------------------------------------------------------------------|--|
|  | Steven R. Williams                                                                                    |  |
|  | Chairman,  and Chief Executive Officer Petroleum Development Corporation, 

Managing  General Partner |  |