QUESTAR SAYS FOUR NEW WELLS VALIDATE
PINEDALE ANTICLINE PRODUCTIVE POTENTIAL

SALT LAKE CITY — Questar Corp. (NYSE:STR) today said results from its drilling program in the Pinedale Anticline in western Wyoming tend to validate and may enhance earlier estimates about the field's productive potential.

In evaluating the new wells, the company compared them with two other Questar Pinedale Anticline wells completed in the first quarter of 2000 — Mesa Unit wells No. 3 and No. 6. Those wells had initial production (IP) rates of 11.4 and 11.1 million cubic feet of gas and 113 and 89 barrels of condensate per day. The average estimated ultimate proved reserve recovery for the two wells is 5-6 billion cubic feet (Bcf) per well.

The company evaluated the four new wells as if flow-tested in the same manner as wells No. 3 and 6, with the following results:

       — Stewart Point 6-32, SENW of Section 32, T33N, R109W, is expected to have a comparative IP of 8-9 million cubic feet per day (MMcfd). The well was drilled to a depth of 13,300 feet and the six fracture treatments have been completed.

       — Mesa 3-20, NENW of Section 20, T32N, R109W, is expected to have a comparative  IP of 10-11 MMcfd. The well was drilled to a depth of 12,903 feet and five of 11 planned fracture treatments have been completed to date.

       — Mesa 13-5, SWSW of Sec. 5, T32N, R109W, is expected to have a comparative IP of 9-10 MMcfd. It was drilled to a depth of 13,106 feet and six of nine planned fracture treatments have been completed to date.

       — Stewart Point 11-33, NESW of Section 33, T33N, R109W, is expected to have a comparative IP of 7-8 MMcfd. The well was drilled to a depth of 12,848 feet and two of eight planned fracture treatments have been completed to date.

Questar said the current drilling program may increase earlier estimates of the potential number of well locations on the company's acreage and tends to confirm estimates of a potential average 5-6 billion cubic feet equivalent of reserves per well. The company said that, while it is too early to make reserve estimates, pressures in the new wells have generally been higher than previously modeled. Correlations of the Stewart Point No. 6-32 and the Mesa No. 3-20 wells have resulted in a broadening of the structural contours on the west side of the Mesa portion of the Anticline. This could increase the number of potentially productive locations on Questar's acreage, the company said.

The two longest producing Questar Pinedale wells with modern completions — Mesa Well No. 15-8 (since January 1998) and Stewart Point No. 3-28 (since November 1998) — have average estimated recoverable reserves of 6.5 to 7.5 billion cubic feet equivalent.

Questar Chairman, President and Chief Executive Officer R.D. Cash said: "While there remain risks with the Pinedale program, we are encouraged that early results tend to validate estimates of the field's productive potential." Cash said risks include the possibility of escalating drilling and development costs, unsuccessful future drilling, and initial test data not being representative of extended performance.

Two Questar subsidiaries — Questar Exploration and Production Co. and Wexpro Co. — have an approximate 60% average working interest in 14,800 gross acres in the Mesa area of the Pinedale Anticline. The Anticline is located southwest of the city of Pinedale, between Rock Springs and Jackson Hole. Based on an 80-acre spacing program, Questar estimates there are potentially 135 to 150 Lance formation wells on its acreage. If 40-acre spacing is deemed appropriate, the potential well locations and reserves could double.

Questar indicated that despite some increased costs due to drilling and mechanical problems, the average cost of future wells could decrease from the previously estimated $2.5 million to between $2.2 million and $2.3 million. The cost would apply to a vertical well with a depth of approximately 13,000 feet in which eight fracture stimulations are employed. Deviated wells required as a result of topography or other surface restrictions, wells requiring intermediate casing due to higher pressures, or wells that need more fracture stimulation will likely have costs ranging from $2.5 million to $2.7 million.

Projected completed-well costs, with production facilities, for the four wells currently being completed are: Stewart Point 6-32, with six fracture stimulations, $ 2 million; Mesa 3-20, 11 stimulations, $2.6 million; Mesa 13-5, nine stimulations, $2.3 million; and Stewart Point 11-33, eight stimulations, $2.5 million. The average per-well completed cost for the four wells would be $2.35 million.

Questar began the current drilling program in mid-August after the Bureau of Land Management issued the Record of Decision for the Pinedale Anticline Environmental Impact Statement on July 28. The Record of Decision allows for the drilling of up to 700 producing well sites. In addition to the Mesa 3 and 6 wells, Questar anticipates that between nine and 11 wells will be drilled and completed on its Pinedale acreage this year. Questar also has an interest in three offset well locations on 80-acre spacing from a well Anschutz Corp. currently is drilling in the NWSW of Section 21, T32N, R109W.

The status of the seven other wells in Questar's drilling program is as follows:

       — Stewart Point 16-29, SESE of Section 29, T33N, R109W, drilled to a depth of 12,774 feet. Mechanical problems have delayed completion.

       — Mesa 7-7, SWNE of Section 7, T32N, R109W, drilling at 12,768 feet.

       — Mesa 7-8, SWNE of Section 8, T32N, R109W, drilling at 11,770 feet.

       — Stewart Point 5-20, SWNW of Section 20, T33N, R109W, drilling at 10,219 feet.

       — Mesa 15-6, SWSE of Section 6, T32N, R109W, drilling at 8,770 feet.

       — Mesa 11-16, NESW of Section 16, T32N, R109W, can be drilled after Nov. 15 (not subject to BLM restrictions).

       — Mesa 3-16d, NENW of Section 16, T32N, R109W. Drilling will commence after Mesa 11-16 is drilled to total depth. It also can be drilled after Nov. 15.

Questar is a $2.3 billion diversified natural gas company headquartered in Salt Lake City. Through subsidiaries, it engages in energy development and production; gas gathering and processing; wholesale gas, electricity and liquids trading; retail energy services; interstate gas transmission and storage; retail gas distribution; and information systems and technologies.

This news release contains some forward-looking statements about the future operations and expectations of Questar Corp. and its affiliates. These statements were made in good faith, and the corporation believes they are reasonable representations of the company's expected performance at this time. Actual results may vary from stated expectations due to a variety of factors. Reserve estimates contained in this news release, unless specifically noted, are not considered proven under standards established by the U.S. Securities and Exchange. The estimates are based on early performance data using accepted engineering practices and could change after extended testing.

# # #