Exhibit No. 12. Questar Pipeline Company Ratio of Earnings to Fixed Charges 12 Months Ended September 30, 1997 1998 (Dollars in Thousands) Earnings Income before income taxes $41,743 $40,549 Plus debt expense 13,395 14,062 Plus allowance for borrowed funds used during construction 174 448 Plus interest portion of rental expense 274 312 $55,586 $55,371 Fixed Charges Debt expense $13,395 $14,062 Plus allowance for borrowed funds used during construction 174 448 Plus interest portion of rental expense 274 312 $13,843 $14,822 Ratio of Earnings to Fixed Charges 4.02 3.74