Exhibit No. 12. Questar Pipeline Company Ratio of Earnings to Fixed Charges Year ended March 31, 1998 1999 (Dollars in Thousands) Earnings Income before income taxes $39,920 $40,614 Plus debt expense 19,903 19,771 Plus allowance for borrowed funds used during construction 226 1,326 Plus interest portion of rental expense 263 377 $60,312 $62,088 Fixed Charges Debt expense $19,903 $19,771 Plus allowance for borrowed funds used during construction 226 1,326 Plus interest portion of rental expense 263 377 $20,392 $21,474 Ratio of Earnings to Fixed Charges 2.96 2.89