Exhibit 31.1
CERTIFICATION
I, Richard W. McCullough, certify that:
| | 1. | I have reviewed this Report on Form 10-K/A of Petroleum Development Corporation. |
| | 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; |
| Date: August 31, 2010 | /s/ Richard W. McCullough | |
| | Richard W. McCullough | |
| | Chief Executive Officer | |
