Exhibit No. 12. Questar Pipeline Company and Subsidiaries Ratio of Earnings to Fixed Charges 12 months ended June 30, 1998 1999 (Dollars in Thousands) Earnings Income before income taxes $45,084 $43,782 Plus debt expense 13,805 15,737 Plus allowance for borrowed funds used during construction 317 1,821 Plus interest portion of rental expense 275 285 $59,481 $61,625 Fixed Charges Debt expense $13,805 $15,737 Plus allowance for borrowed funds used during construction 317 1,821 Plus interest portion of rental expense 275 285 $14,397 $17,843 Ratio of Earnings to Fixed Charges 4.13 3.45