Northern Natural Gas Company                                              First Revised Sheet No. 230
FERC Gas Tariff                                                                           Superseding
Fifth Revised Volume No. 1                                                     Original Sheet No. 230

                               GENERAL TERMS AND CONDITIONS

              E.  Contracts to Divert Supply During A Curtailment
                  -----------------------------------------------

                  Northern will make its website available for "Curtailment Supply Wanted"
                  and "Curtailment Supply Available" so that firm Shippers can enter into
                  voluntary contractual arrangements to provide for supply in the event of
                  a curtailment.  Under such an arrangement, a curtailment supplier will,
                  during the period of curtailment, divert its supply by limiting its
                  takes up to the quantity specified in the contract within four hours of
                  the emergency curtailment announcement.  Contract parties who do not
                  receive gas under said contract during a curtailment must pursue
                  whatever remedies they have for breach of contract.

              F.  Curtailment Compensation Plan
                  ------------------------------

                  In the event a firm Shipper, who has not entered into a contract to have
                  its supply diverted, as described in Section 19.E. above, has its supply
                  diverted during a curtailment, or is not permitted to use or schedule
                  capacity up to its initial pro rata curtailment share of capacity during
                  the curtailment due to an emergency exemption, the following
                  compensation procedure will be followed:

                  1.  In the event that scheduled and confirmed flowing gas supplies are
                      diverted from a firm shipper, the measure of daily compensation for
                      supply shall be a rate of two hundred seventy-five percent (275%) of
                      the daily arithmetic average of the three (3) Price discovery points
                      of Panhandle, Tx.- Okla. Northern (demarc) and Northern (Ventura as
                      reported in the publication "Gas Daily" under its Daily Price
                      Summary column per MMBtu, for the day(s) of curtailment, plus one
                      hundred percent (100%) of all daily transportation demand charges.

                      In the event a Shipper is unable to use or schedule its capacity up
                      to its initial pro rata curtailment share of capacity during the
                      curtailment due to an emergency exemption, the measure of daily
                      compensation is one hundred percent (100%) of all daily
                      transportation demand charges for the difference between the
                      Shipper's initial pro rata curtailment share of capacity and the
                      adjusted level of pro rata curtailment capacity.

                      This provision for compensation is considered a liquidated damages
                      clause and therefore, shall be the only measure of compensation for
                      parties who did not receive their scheduled quantity during the
                      curtailment and/or were not able to use their capacity up to their
                      initial pro rata curtailment share of capacity.  Northern will take
                      all reasonable steps to collect such compensation from the parties
                      receiving gas above their scheduled quantity or capacity above their
                      initial pro rata share during the curtailment and will pay any
                      amounts collected under this provision to the parties who did not
                      receive their scheduled quantity or their initial pro rata
                      curtailment share of capacity during the curtailment.  However, in
                      the event Northern is unable to collect such compensation from the
                      responsible parties after taking all reasonable steps, Northern
                      shall not be liable for payment to the parties entitled to such
                      compensation.

                  2.  In no event will Shippers involved in a dispute as to the diversion
                      of their gas during a curtailment seek to hold Northern liable for
                      direct or consequential damages resulting from the diversion of gas.
                      Further, it is clearly understood that Northern will act merely as a
                      conduit with respect to any role it may have in the collection of
                      monies as payment for diverted gas.
Issued by: Mary Kay Miller, V.P. Regulatory & Government Affairs
Issued on: January 25, 2006                                             Effective: February 25, 2006