Northern Natural Gas Company                                  Substitute Eighth Revised Sheet No. 226
FERC Gas Tariff                                                                           Superseding
Fifth Revised Volume No. 1                                       2 Substitute 7 Revised Sheet No. 226

                                    GENERAL TERMS AND CONDITIONS

          19.      LIMITATIONS OF NORTHERN'S OBLIGATION TO
                   PROVIDE FIRM SERVICES
                   ---------------------------------------

               A.  General

                   1.  In the event a curtailment must be effected, the smallest affected area will be
                       localized beginning with individual points, followed by an operational zone,
                       Market/Field Area, and up to the entire system, in that order.  Curtailment will
                       proceed in the following sequence:

                       (i)  TI will be curtailed on the basis of lowest price first.

                      (ii)  LFT service with Limited Days remaining for the month.
                            a.  lowest price will be limited first;
                            b.  greater number of remaining Limited Days second;
                            c.  and then pro rata.

                     (iii)  Firm service, including LFT with no Limited Days remaining for the month, at
                            primary or alternate points will then be curtailed on a pro rata basis.

                   2.  If Shipper takes gas in excess of the volume of gas authorized for delivery on any
                       day Northern has ordered reduced deliveries, Shipper shall be subject to a penalty
                       for takes of gas in excess of the authorized volume, without any tolerance.  The
                       penalty shall be equal to the Punitive DDVC rate set forth on Sheet No. 53.
                       Penalty revenues shall be credited to Shippers in accordance with Section 57 of
                       the GENERAL TERMS AND CONDITIONS of this Tariff.

                   3.  If TI receipt point volumes continue to flow during a curtailment at Northern's
                       request, such volumes during such curtailment will not be subject to receipt point
                       scheduling penalties.

                   4.  Northern shall also have the right to reasonably limit supply service and/or
                       reduce receipts or deliveries of natural gas in conjunction with the throughput
                       capacity under Throughput Service Agreements on part or all of Northern's system
                       according to the above 1) to permit maintenance, repair, overhaul, replacement or
                       construction of pipelines, compressors, metering, regulating and other production,
                       and transmission facilities and equipment; 2)  to assure the availability of
                       capacity for receipts or deliveries equitably under Northern's firm Rate Schedules
                       included in this Tariff in cases where natural gas does not conform to the quality
                       specifications contained in the Tariff.  Northern shall provide Shipper reasonable
                       advance notice of routine maintenance, repair, overhaul or replacement.

                   5.  Unless Northern and Shipper mutually agree to limit hourly takes to less than 6.3%
                       for incremental entitlement, Northern shall have the right on a nondiscriminatory
                       basis to restrict the hourly takes of gas by the Shipper in the Market Area to
                       6.3% of the entitlement plus any excess volumes authorized under the Firm Service
                       Agreement.  Such restrictions may be ordered by Northern, when necessary in
                       Northern's judgment to maintain operational integrity, and shall be complied with
                       by the Shipper.  Electronic flow measurement and flow control equipment is
                       required at any point where Northern and a Shipper have agreed to lower hourly
                       takes.  The hourly take rate will be applicable to the  primary point(s) on the
                       Shipper's Service Agreement only.  If the Shipper nominates an alternate point
                       (including capacity release) the Shipper may retain the more restrictive
                       contractual hourly flow limitation if capacity is available at the point.
                       Alternatively, Northern and the Shipper may mutually agree to a different hourly
                       flow limitation at the alternate point.  In the event a Shipper that has agreed to
                       limit hourly takes to less than 6.3% for incremental entitlement does not comply
                       with Northern's order to restrict hourly takes, Shipper shall pay a penalty equal
                       to the Punitive DDVC charge set forth on Sheet No. 53.  Penalty revenues shall be
                       credited to Shippers in accordance with Section 57 of the GENERAL TERMS AND
                       CONDITIONS of this Tariff.

                       In the Field Area, Northern and Shipper may mutually agree to hourly takes of
                       4.16% of the new or extended entitlement at the delivery point, subject to the
                       necessary construction of facilities and Northern being operationally capable of
                       providing the hourly flow rate.
Issued by: Mary Kay Miller, V.P. Regulatory & Government Affairs
Issued on: August 22, 2008                                                   Effective: June 1, 2008
Filed to comply with order of the Federal Energy Regulatory Commission,
Docket No. RP08-262-001, issued July 29, 2008, 124 FERC 61,104