Northern Natural Gas Company                                             Third Revised Sheet No. 259A
FERC Gas Tariff                                                                           Superseding
Fifth Revised Volume No. 1                                              Second Revised Sheet No. 259A

                                     GENERAL TERMS AND CONDITIONS

    formula.  The load forecast formula will be based on the latest available forecasted
    temperatures at 8:00 a.m. the day before gas flow, using the National Ocean and Atmospheric
    Administration (NOAA) weather forecasting service.  The forecasted volume will be based on
    three years of historical daily volume flows recorded in Northern's Gas Volume Allocation
    (GVA) system at the non-telemetered points at the forecasted temperature based on the
    season, month and day of the week.  Northern and Shipper may agree to adjust the formula to
    equal the MDQ for verifiable changes to the historical daily volume flows.  The formula is
    as follows:

        Forecasted volume = Intercept + Feb + Mar + Apr + May + Jun + Jul + Aug
        + Sep + Oct + Nov + Dec + Season + Year + Holiday + Mon + Tues + Weds + Thurs
        + Fri + Sat + Temp + Temp2 + Lag High + 7 Day Avg Temp

    Each point is mapped to the closest weather station where daily forecasts can be
    identified.  The Shipper and Northern will review and agree to the load forecast formula
    results prior to committing to the program.  Northern and Shipper may agree to use a
    different load forecast formula, subject to Northern filing such formula with the
    Commission.

    Standards for Operational Zone Boundary Changes.  Shipper may request a change in the
    currently effective Operational Zone boundaries or may request that a delivery point(s) be
    moved from one Operational Zone to another.  Such request shall be made in writing and
    shall set forth the name of the Shipper, the delivery point(s) involved, and the reasons
    for requesting the change or move.

    a. Northern shall evaluate any such request using the following requirements:

       i. Shipper has had delivery point(s) in the Operational Zone to which Shipper has
          requested the delivery point(s) be changed or moved for a period of at least twelve
          (12) consecutive months;

      ii. circumstances at the particular delivery point(s) that Shipper desires to change or
          move have changed from those existing at the time the existing boundaries were
          established, e.g., a change in ownership of the delivery point(s); a change in the
          size of the load at the delivery point(s); or an intervening change in Northern's
          tariff which, in conjunction with the change or move in delivery point(s), would
          simplify Shipper's nomination process; and

     iii. the change will not result in negative operational consequences or other system
          management problems for Northern or other shippers.  As part of the assessment of the
          operational and system management consequences of the requested change, Northern
          shall perform a flow study, based on the three most recent scheduling allocations in
          the Operational Zone in which the delivery point(s) specified in the Shipper's
          request currently are located, demonstrating how those allocations would have been
          affected had the delivery point(s) not been in that Operational Zone at the time of
          the allocations.  To the extent Northern demonstrates that increased allocations,
          SOL, SUL or Critical Days or other operational or system management impacts will
          occur as a result of the change, the request will be denied.

    b. If Northern determines that the requirements set forth in subsection a. have been met,
       Northern shall make a Section 4 tariff filing requesting Commission approval to make the
       proposed change or move.  No such change or move shall be made until Commission approval
       has been obtained.

    c. If the request is granted and negative operational or other adverse consequences result,
       Northern has the right to make a filing with the Commission to (1) restore the
       Operational Zone boundaries that existed prior to the change, or (2) return the delivery
       point(s) to the original Operational Zone.  Pending the outcome of the filing before the
       Commission, Northern has the right to take interim actions that address the negative
       operational impact or other adverse consequences.  Such interim actions include, but are
       not limited to, the actions set forth in c(1) and c(2) above.
Issued by: Mary Kay Miller, V.P. Regulatory & Government Affairs
Issued on: August 27, 2010                                             Effective: September 29, 2010