TSP Name: Northern Natural Gas Company TSP: 784158214 Notice ID: 097784 Notice Type: TSP Capacity Offering Subject: OPEN SEASON FOR GENERALLY AVAILABLE FIELD AREA BACKHAUL DELIVERIES Critical: N Post Date/Time: 10/28/2025 01:56 PM Notice Status: Initiate For Gas Day(s): 10/28/2025 - 11/12/2025 Notice Effective Date/Time: 10/28/2025 01:56 PM Notice End Date/Time: 11/12/2025 02:00 PM 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 receipt points located in Northern's Field Area MIDs 1-16B for deliveries in the Field Area MIDs 1-16A. Bids that use forward haul capacity will not be considered in this open season. Depending on the delivery point(s) selected in the open season, availability of a particular receipt point may be limited. Capacity is available now or any time in the future. Northern is willing to accept bids as follows: · For bids for backhaul service up to and including 12-consecutive months, the bid quantity must be equal for each month across the winter season (November-March) and each month across the summer season (April-October) for the term of the bid. · For bids for backhaul services greater than 12-consecutive months, the bid quantities may incrementally increase during the initial months within the first year of the bid; provided however, the bid quantity must be equal for each month across the winter season (November-March) and each month across the summer season (April-October) during the final full year (12 consecutive months) of the term of the bid. · The actual capacity available will be determined based on the specific delivery point(s) requested in the open season. 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: October 28, 2025 Closes: November 12, 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 or Jason Thomsen at (402) 398-7469. 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 for alternate point use. 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. Northern filed a Section 4 rate case on July 1, 2025, to recover the asset modernization and maintenance capital being invested in its pipeline system to comply with pipeline safety requirements and maintain reliability of service to its customers. This filing reflects an increase to the maximum rates. Increased rates may become effective as early as January 1, 2026. Contiguous Paths A customer may request contiguous backhaul service to increase the value of its bid. A contiguous path is two or more contract paths where the receipt point of one path is the same location as the delivery point of another path. For evaluation purposes, the net present value (NPV) calculation of a request with contiguous paths will be performed for each individual path and then added together. Contiguous service requests may contain one or more contiguous point(s) where the receipt point of one path is the same location as the delivery point of another path. For purposes of contiguous service requests, Northern will aggregate the NPVs of requests containing the following contiguous points: Pampa Pooling Point (POI #79530), Beaver Pooling Point (POI #54576), Mullinville Pooling Point (POI #54575), Mid Continent Pool (POI #61020), Brownfield Pooling Point (POI 79387), Bushton Pooling Point (POI #54577), and any of Northern's Field Area deferred delivery points associated with physical points. For evaluation purposes, the NPV calculation of a request with contiguous paths will be performed for each individual path and then added together for evaluation purposes. Northern reserves the right to (1) consider other contiguous points not denoted in this posting; (2) reject all or portions of a contiguous service request that requires displacement of capacity in order to accommodate the combination of receipt and delivery points in a contract; and (3) require that contiguous service requests be split into multiple contracts to manage capacity constraints. To the extent that a customer's request requires multiple contracts, Northern and customer may agree to adjust the MDQ, subject to available capacity, to account for fuel requirements. Customers that use storage points must have an active storage contract. Parties that do not have an active storage contract may request one. In the event Northern requires multiple contracts to fulfill a contiguous service request, the average rate will be applied to each contract. Bids and Bid Evaluation 1) Customers may bid any term with a start date now or any time in the future, for annual or seasonal backhaul service; however, the end date must be March 31, or October 31. 2) 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. o Northern reserves the right to reject any bid at less than maximum tariff rates. For bid evaluation purposes, the assumed reservation component for fixed 1-part rate bids will be the 1-part rate less: o $0.015/Dth/day for receipt points and delivery points in MIDs 1-7 o $0.045/Dth/day for receipt points in MIDs 8-16B for delivery to points in MIDs 1-7 o $0.02/Dth/day for receipt points MIDs 8-16B for delivery to points in MIDs 8-16A These reductions will be applied to one path of a contiguous 1-part bid. 3) Realignments without an incremental rate bid will have no NPV. 4) For bid evaluation purposes, Northern will use the sum of the NPVs from all contiguous paths bid in the open season to calculate the NPV. 5) Northern may consider contingencies in the bids. 6) 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. 7) 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. 8) Transportation service agreements are to be executed by customer within 30 calendar days of tender by Northern. 9) 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. 10) The reservation rate bid is binding for backhaul throughput service. 11) 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. 12) 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. 13) 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.