TSP Name: Northern Natural Gas Company TSP: 784158214 Notice ID: 108246 Notice Type: Planned Service Outage Subject: PLANNED SERVICE OUTAGES - JUNE 2026 THROUGH OCTOBER 2026 Location: MARKET AND FIELD AREA Critical: N Post Date/Time: 06/17/2026 11:20 AM Notice Status: Supersede Prior Notice: 108042 For Gas Day(s): 06/17/2026 - 10/31/2026 Notice Effective Date/Time: 06/17/2026 11:20 AM Notice End Date/Time: 11/01/2026 08:59 AM Required Response Indicator Description: 5-No response required Notice Text: Northern has scheduled the following service outages that will affect operating capacity within the months of June 2026 through October 2026. Please review the Planned Service Outage Summaryfor detailed information related to each outage. A brief description of the most recent change(s) to the Planned Service Outage Summary follows. Market Area Allocation Group(s)/Point(s): North Branch (Group 835) and North Branch Receipt Points (Group 1151) Location: Northern's pipeline between Hugo, Minnesota, and North Branch, Minnesota. Project Description: Pipeline maintenance Month: June 2026 and July 2026 Direction of Flow: Delivery: North Branch (Group 835) Receipt: North Branch Receipt Points (Group 1151) Capacity Impact: Northern does not anticipate primary firm service will be impacted for North Branch (Group 835) and North Branch Receipt Points (Group 1151). Revision: Capacity impacts for North Branch (Group 835) and North Branch Receipt Points (Group 1151) have been updated for June 2026. Allocation Group(s)/Point(s): Viking/NNG Pierz ITE (POI 61667) Location: Northern's compressor station located in Pierz, Minnesota Project Description: Compressor station maintenance Month: June 2026 Direction of Flow: Delivery: Viking/NNG Pierz ITE (POI 61667) Receipt: Viking/NNG Pierz ITE (POI 61667) Capacity Impact: Primary firm service will be impacted for Viking/NNG Pierz ITE (POI 61667). Revision: Capacity impacts for Viking/NNG Pierz ITE (POI 61667) have been updated for June 2026. Allocation Group(s)/Point(s): Ventura South (Group 735) Location: Northern's pipelines and compressor stations between Ventura, Iowa, and Ogden, Iowa Project Description: Compressor station and pipeline maintenance Month: April 2026 through July 2026 Direction of Flow: Delivery: Ventura South (Group 735) Capacity Impact: Northern does not anticipate primary firm service will be impacted for Ventura South (Group 735). Revision: Capacity impacts for Ventura South (Group 735) have been updated for June 2026 and July 2026. Field Area Allocation Group(s)/Point(s): PEPL/NNG Mullinville (POI 173) and ANR/NNG Greensburg (POI 179) Location: Northern's compressor station located in Mullinville, Kansas Project Description: Compressor station maintenance Month: June 2026 through July 2026 Direction of Flow: Delivery: ANR/NNG Greensburg (POI 179) Receipt: PEPL/NNG Mullinville (POI 173) Capacity Impact: Northern does not anticipate primary firm service will be impacted for PEPL/NNG Mullinville (POI 173). Primary firm service will not be impacted for ANR/NNG Greensburg (POI 179). Revision: Capacity impacts for ANR/NNG Greensburg (POI 179) have been updated for June 2026 and included for July 2026. Allocation Group(s)/Point(s): Sunray Low (Group 10) and Sunray High (Group 32) Location: Northern's compressor station located in Sunray, Texas Project Description: Compressor station and pipeline maintenance Month: June 2026 through July 2026 Direction of Flow: Receipt: Sunray Low (Group 10) and Sunray High (Group 32) Capacity Impact: Primary firm service will not be impacted for Sunray High (Group 32) and Sunray Low (Group 10). Revision: Capacity impacts for Sunray Low (Group 10) and Sunray High (Group 32) have been updated for July 2026 and included for August 2026. Please see Operationally Available Capacityon Northern's website for current flow information and the Field Area Group Allocation Mapsand Market Area Group Allocation Mapsfor a list of impacted points. If you have any questions, contact your customer service or marketing representative.