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Exhibit 23.06

ENGINEER'S CONSENT

        We consent to the reference of our appraisal reports for Questar Exploration and Production Company as the years ended December 31, 1998, 1999, and 2000, incorporated herein by reference.

Malkewicz Hueni Associates, Inc

/s/  GREGORY B. HUENI

February 22, 2002

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Exhibit 23.06

ENGINEER'S CONSENT