Northern Natural Gas Company

Fifth Revised Volume No. 1

Effective Date: 02/21/2009, Docket: RP01-223-004, Status: Effective

Fifth Revised Sheet No. 143 Fifth Revised Sheet No. 143 : Pending

Superseding: Substitute Fourth Revised Sheet No. 143

RATE SCHEDULE IDD

Interruptible Deferred Delivery Service

1. AVAILABILITY:

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

This Rate Schedule is available to any Shipper with an effective Firm or

Interruptible Throughput Service Agreement as contained in Northern's FERC

Gas Tariff ("Tariff"). Shipper must also have an effective Interruptible

Deferred Delivery Service Agreement (Service Agreement) with Northern in the form

included in this Tariff prior to service commencing under this Rate

Schedule.

Service under this Rate Schedule shall be available on a year-round basis.

Shipper may request Northern on a daily basis to accept natural gas volumes

delivered by Shipper under Rate Schedule TF, TFX, VFT, LFT or TI (injections) or to

make volumes of natural gas available for transportation (withdrawals).

Volumes accepted by Northern shall be held in an account for Shipper and

shall be made available to Shipper subject to the terms of this Rate

Schedule and as otherwise provided. Available IDD capacity will be posted

on the EBB.

Shipper shall comply with the provisions of this Rate Schedule and the terms

of its Service Agreement. Shipper shall pay the maximum rate for service herein as

set forth in this Tariff unless a lower rate is established in the Service Agreement

or confirmed by Northern in writing. The daily capacity available for service

pursuant to this Rate Schedule shall be the daily Interruptible Deferred Quantity

specified in Shipper's Service Agreement.

2. APPLICABILITY AND CHARACTER OF SERVICE:

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

Service under this Rate Schedule shall be interruptible up to Shipper's

daily Interruptible Deferred Quantity as specified in