Williston Basin Interstate Pipeline Co.

Second Revised Volume No. 1

Effective Date: 08/01/1999, Docket: RP99-410-002, Status: Effective

Sub Second Revised Sheet No. 176A Sub Second Revised Sheet No. 176A : Effective

Superseding: First Revised Sheet No. 176A

GENERAL TERMS AND CONDITIONS (Continued)

1. DEFINITION OF TERMS (Continued)

1.17 The term "gigacalorie" means 1 billion calories and the

term "gigajoule" means 1 billion joules. The standard quantity

for nominations, confirmation and scheduling is gigacalories per

gas day in Mexico and gigajoules per gas day in Canada. One

calorie is the amount of heat required to raise the temperature

of one kilogram of water one degree Celsius. The joule is the

"Systeme International" unit of work or energy. One joule is the

amount of work done when an applied force of 1 newton moves

through a distance of 1 metre in the direction of the force. For

commercial purposes, the standard conversion factor between

dekatherms and gigacalories is 0.251996 gigacalories per

dekatherm and between dekatherms and gigajoules is 1.055056

gigajoules per dekatherm. The standard joule is the joule

specified in the IS system of units. The International Btu is

specified for use in the gas measurement standards of the

American Gas Association, the American Petroleum Institute, the

Gas Processors Association and the American Society for Testing

Materials. For non-commercial purposes, these associations note

that the exact conversion factor is 1.05505585262 gigajoules per

dekatherm.

1.18 The term "gross heating value" means the number of Btu's

produced by the complete combustion, at a constant pressure, of

the amount of gas which would occupy a volume of one (1) cubic

foot at a temperature of 60 degrees Fahrenheit on a dry basis and

at a pressure of 14.73 psia with air of the same

temperature and pressure as the gas, when the products of

combustion are cooled to the initial temperature of the gas and

air, and when the water formed by combustion has condensed to the

liquid state.

1.19 The term "Interruptible Capacity Quantity" means the

maximum interruptible quantity of natural gas in dkt which

Shipper shall be allowed to store in Transporter's storage

facilities, as established in the Service Agreement.

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