Questar Southern Trails Pipeline Company

Original Volume No. 1

Effective Date: 10/24/2003, Docket: RP03-612-000, Status: Effective

First Revised Sheet No. 74 First Revised Sheet No. 74 : Effective

Superseding: Original Sheet No. 74

GENERAL TERMS AND CONDITIONS

12.3 Unit of Measurement and Metering Base. The standard reporting

basis for Btu is 14.73 psia and 60 degrees F (101.325 kPa, and 15 degrees C,

and dry). The standard reporting basis for gigacalorie is 1.035646 Kg/cm2 and

15.6 degrees C, and dry. The standard reporting basis for gas volumes is

cubic foot at standard conditions of 14.73 psia, and 60 degrees F, and dry.

For gas volumes reported in cubic meters, the standard conditions are 101.325

kPa and 15 degrees C, and dry.

12.4 Atmospheric Pressure. For the purpose of measurement,

calculation and meter calibration, the average absolute atmospheric

(barometric) pressure will be based on the actual altitude at each point of

measurement irrespective of variations in natural atmospheric pressure from

time to time. When electronic computer measurement is used, the atmospheric

pressure will be the barometric pressure calculated for the elevation at the

point of measurement.

12.5 Flowing Temperature. The temperature of the gas will be

determined at the points of measurement by means of a properly installed

recording thermometer or continuous electronic transducer input to a computer

(of standard manufacture selected by Southern Trails). When used with orifice

meters, the gas temperature device shall be installed and operated, and the

gas temperature quantities computed, in accordance with AGA Report No. 3, Part

2, API Chapter No. 21.1, and API Chapter 14.3. When used with turbine meters,

the gas temperature device shall be installed and operated, and the gas

temperature quantities computed, in accordance with AGA Report No. 7 and API

Chapter 21.1. When used with rotary meters, the gas temperature device shall

be installed and operated, and the gas temperature quantities computed, in

accordance with AGA ANSI B109.3 and API Chapter 21.1. When used with

ultrasonic meters, the gas temperature device shall be installed and operated,

and the gas temperature quantities computed, in accordance with AGA Report No.

9 and API Chapter No. 21.1.

12.6 Gross Heating Value and Specific Gravity.

(a) The determination of gross heating value and specific

gravity will be made from the composition by calculation using physical gas

constants for gas compounds as outlined in GPA Standard 2145-03 and GPA

Standard 2172-96, with any subsequent amendments or revisions that Southern

Trails may adopt.