TSP Name: Northern Natural Gas Company TSP: 784158214 Notice ID: 110314 Notice Type: TSP Capacity Offering Subject: OPEN SEASON FOR GENERALLY AVAILABLE DEMARC BACKHAUL DELIVERIES Critical: N Post Date/Time: 08/07/2026 11:05 AM Notice Status: Initiate For Gas Day(s): 08/07/2026 - 08/18/2026 Notice Effective Date/Time: 08/07/2026 11:05 AM Notice End Date/Time: 08/19/2026 08:59 AM Required Response Indicator Description: 5-No response required Notice Text: Open Season Overview Northern Natural Gas Company (Northern) is hereby soliciting binding bids for backhaul throughput service from NNG FIELD/MKT DEMARCATION (POI 37654) or DEMARC DEF. - DELIVERY (POI 62389) for deliveries in the Field Area MIDs 1-16A. Capacity is available now or any time in the future. Northern is willing to accept bids as follows: · The actual capacity available will be determined based on the specific delivery point(s) requested in the open season. · Notable Capacity for deliveries South of Pampa (Group 19D) outlined below: Monthly capacity available through June 2027: Aug26 Sep26 Oct26-Nov26 Dec26 Jan27 Feb27 Mar27 Apr27 May27 Jun27 273,100 299,767 331,850 329,350 326,850 316,850 301,850 250,850 190,767 136,100 Monthly capacity available beginning July 2027: Jan - Apr May Jun - Aug Sep Oct - Dec 166,850 134,767 108,100 134,767 166,850 * Maximum daily quantity bid for annual service for deliveries South of Pampa is limited to 108,100 Dth/day Interested customers may request firm backhaul throughput service by submitting a signed binding Bid Form. Customers requesting service are responsible for ensuring arrangements have been made for any capacity necessary on any upstream or downstream pipeline for their volumes to be confirmed during the nomination and scheduling process. Northern will award capacity in a manner consistent with the Open Season Procedures discussed below. Open Season Timing Commences: August 7, 2026 Closes: August 17, at 2:00 p.m. CCT To be considered in the open season, customer's signed binding Bid Form must be received by the close of the open season. If you have any questions, please contact your Account Manager. Open Season Procedures Submit your binding Bid Form to Northern by either: Facsimile to (402) 398-7413 Email to NNGOpenSea@nngco.com The Bid Form must include: Requested rate Receipt point(s) Delivery point(s) Volume In-service date Term Minimum amount of capacity willing to accept, if applicable Increments of capacity willing to accept, if applicable Paths, if applicable Contingencies, if applicable Rates Customers may bid the maximum tariff rate, 2-part fixed rate, or 1-part fixed rate. All bids other than the maximum tariff rate will be subject to additional charges, detailed in the General Terms and Conditions, when alternate points are used. Additional charges for one-part and two-part fixed rates will be applied to the monthly charges such that the total charges between reservation and commodity do not exceed Northern's maximum tariff rate. Northern will allocate the value of rate among the contiguous paths such that no path will be above the maximum rates for evaluation purposes but will be subject to additional rates if alternate receipt or delivery points are used. As previously communicated, Northern filed a Section 4 rate case on July 1, 2025. In an Order dated February 25, 2026, the Chief Judge granted a motion to implement interim settlement rates effective February 01, 2026. For evaluation purposes, Northern's interim settlement rates shall be used as the maximum applicable tariff rates. Bids and Bid Evaluation 1) Customers may bid any term with a start date now or any time in the future for annual, seasonal, or monthly service, however, must contain an end date at the end of the month. 2) Bids for capacity that starts greater than 1 year after the start of the evaluation period, must be for an annual term and the bid quantity must be uniform across the term of the bid up to the annual available capacity (108,100 Dth/day). Bids for quantities greater than the annual available capacity may include non-uniform capacity quantities, however, must be for all months that the non-uniform capacity is available. Bids for capacity that start greater than 1 year after the start of the evaluation period must be for a term of greater than or equal to five consecutive years. 3) Bids are subject to the General Terms and Conditions incorporated herein by reference. 4) Northern's Bid Evaluation: o The capacity will be awarded to the highest bid(s) based on a determination of the best bid, or combination of bids that result in the highest net present value (NPV) of reservation revenue, on a per unit of capacity basis. o Northern has the right to aggregate bids, or portions of bids, that generate the highest NPV to Northern. o Northern reserves the right to reject any bid, or portion thereof, that contains a discount. o The NPV per unit will be determined by discounting the cash flow (using the FERC interest rate) generated from the reservation rate multiplied by the volume for each month, by bid, and then dividing the NPV by the maximum daily quantity bid for annual service (12 consecutive months of uniform bid quantity). For bids for less than annual service, the highest maximum daily quantity bid for any month will be used in the calculation in lieu of MDQ bid for annual service. o Northern reserves the right to reject any non-maximum tariff rate bids that extend past the Evaluation Period. o The evaluation period will be from August 19, 2026, through October 31, 2036. For bid evaluation purposes, the assumed reservation component for fixed 1-part rate bids will be the 1-part rate less: o $0.040/Dth/day for delivery to points in MIDs 1-7 o $0.018/Dth/day for delivery to points in MIDs 8-16A These reductions will be applied to one path of a contiguous 1-part bid. 5) Realignments without an incremental rate bid will have no NPV. 6) For bid evaluation purposes, Northern will use the sum of the NPVs from all contiguous paths bid, using points defined within the bid form, to calculate the total NPV. 7) Northern may consider contingencies in the bids. 8) Customers requesting service are responsible for ensuring arrangements have been made for any capacity necessary on any upstream or downstream pipeline for their volumes to be confirmed during the nomination and scheduling process. 9) Bidder(s) must meet the creditworthiness provisions of Northern's tariff. Upon request by Northern, Bidder shall provide appropriate credit assurance within ten (10) calendar days of Northern's request. If a non-creditworthy Bidder fails to provide the appropriate security, Northern may award the capacity to the next best bid(s) or proceed to remarket the capacity, and Bidder will be liable for any difference in value of the bids, in addition to any other remedies available by law. 10) Transportation service agreements are to be executed by customer within 30 calendar days of tender by Northern. 11) The backhaul service being offered in this open season is generally available capacity. Northern is not considering construction to expand its pipeline system as part of this open season but may construct minor facilities to provide the service requested. 12) The reservation rate bid is binding for backhaul throughput service. 13) Northern will evaluate and award capacity for incremental bids based on the terms of this open season. Any remaining capacity will be released as generally available capacity. However, in accordance with Northern's tariff, Northern will process any requests for realignment without an incremental rate in the order they were received within seven (7) workdays of the close of the open season. 14) Northern and customer may agree to amend the service agreement, including alternate point rights, as allowed by Northern's Tariff, at any time after award of the capacity. 15) Northern and customer may agree to extension rights for all or a portion of the contract MDQ. If you have questions, please contact your marketing representative.