TSP Name: Northern Natural Gas Company TSP: 784158214 Notice ID: 095592 Notice Type: TSP Capacity Offering Subject: OPEN SEASON FOR GENERALLY AVAILABLE DEMARC AND VENTURA INCLUDING EAST LEG CAPACITY FOR NOVEMBER 2025 Critical: N Post Date/Time: 09/17/2025 02:22 PM Notice Status: Initiate For Gas Day(s): 09/17/2025 - 10/03/2025 Notice Effective Date/Time: 09/17/2025 02:22 PM Notice End Date/Time: 10/03/2025 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 up to 1,720 Dth/day (See attached map) of firm throughput service for 1,120 Dth/day from NBPL/NNG Ventura (POI 192) and 600 Dth/day from NNG Field/MKT Demarcation -16B (POI 37654) for delivery to points between Demarc and Ventura including points east of Ogden on the East Leg (See attached points) in Northern's Market Area commencing on November 1, 2025. Notable capacity inside the map: · 600 Dth/day of receipt from Field/MKT Demarcation -16B (POI 37654) · 1,120 Dth/day of receipt from NBPL/NNG Ventura (POI 192) · Up to 1,720 Dth/day of delivery east of Ogden on the East Leg The attached map provides possible delivery volumes along the mainline. Branch line capacities may be less than what is provided in the map. (See attached map) The bid quantity must be equal for each month across the winter season (November-March) and each month across the summer season (April-October) 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 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 Commenced: September 17, 2025 Closes: October 2, 2025, 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 - NBPL/NNG Ventura (POI 192) and/or NNG Field/MKT Demarcation -16B (POI 37654) 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 Contingencies, if applicable The reservation rate bid is binding for firm throughput service. The term of service for any bid must start on November 1, 2025, and end on a March 31 or an October 31. The bid quantity must be equal for each month across the winter season (November-March) and each month across the summer season (April-October) of the term of the bid. 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, using revenues from the start of the service through October 31, 2027. Northern has the right to aggregate bids or portions of bids, that generate the highest total NPV to Northern. 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. The following receipt points will be considered in this open season: NBPL/NNG Ventura (POI 192) and NNG Field/MKT Demarcation -16B (POI 37654) . Northern reserves the right to reject any bid(s) less than maximum rates. Northern reserves the right to reject any bid(s) which are subject to contingencies. Capacity awarded in the open season may require a new contract. Transportation contracts are to be executed by customers prior to service commencing or within thirty (30) calendar days of tender by Northern. Northern and customer may agree to amend the service agreement, as allowed by Northern's Tariff, at any time after award of the capacity. Northern will evaluate and award capacity for incremental bids based on the terms of this open season. Any remining capacity will be released as generally available capacity. However, in accordance with Northern's Tariff, Northern will process any request for realignment without incremental value in the order they were received within seven work days of the close of the open season. Customer(s) must meet the creditworthiness provisions of Northern's Tariff. Upon request by Northern, customer shall provide appropriate credit assurance, including credit assurance for the construction of facilities, within ten (10) calendar days of Northern's request. If a non-creditworthy customer fails to provide the appropriate security, Northern may award the capacity to the next best bid(s) or proceed to remarket the capacity, and customer will be liable for any difference in value of the bids, in addition to any other remedies available by law. The results of this open season will be posted on Northern's website.