Northern Natural Gas Company

Fifth Revised Volume No. 1

Effective Date: 10/01/2007, Docket: RP07-648-000, Status: Effective

Sixth Revised Sheet No. 301A Sixth Revised Sheet No. 301A : Effective

Superseding: Fifth Revised Sheet No. 301A

GENERAL TERMS AND CONDITIONS

(iv) Northern shall determine at the time of filing its PRAs, based on

its system configuration and operational experience whether

mainline compression was used in connection with transactions

involving certain MIDS. At the time of filing, Northern will

provide a full explanation of any changes in system configuration

and operational experience related to the use of mainline

compression, and parties will have the right to challenge any

proposed changes in the PRA filing.

Market Area "M/L Fuel Percentage" (Mid 17)

------------------------------------------

The Market Area M/L fuel calculation is one Fuel Percentage

applicable to all of Northern's Market Area receipts. All fuel consumed

at facilities in the Market Area is aggregated for the applicable season,

as adjusted for known and measurable changes, and divided by all

throughput received into the Market Area over the same time period.

FDD Storage Fuel

----------------

The FDD Storage Fuel calculation is one Fuel Percentage applicable to FDD

volumes injected during the Injection Period. The FDD Storage Fuel

Percentage is calculated by dividing the applicable twelve-month actual

storage fuel, as provided for in the PRA Settlement, by the projected FDD

Storage injections during the Injection Period.

Unaccounted-For (UAF)

---------------------

The Unaccounted-for percentage is calculated by dividing the

twelve-month actual unaccounted-for gas for the respective twelve-month

period ending December 31, by the throughput for the same twelve-month

period. UAF is not collected for transportation from any receipt point in

any MID to the delivery point at MID 16B.