TSP Name: Northern Natural Gas Company TSP: 784158214 Notice ID: 092452 Notice Type: Planned Service Outage Subject: PLANNED SERVICE OUTAGES - JULY 2025 THROUGH NOVEMBER 2025 Location: MARKET AND FIELD AREA Critical: N Post Date/Time: 07/03/2025 02:11 PM Notice Status: Supersede Prior Notice: 092198 For Gas Day(s): 07/03/2025 - 11/30/2025 Notice Effective Date/Time: 07/03/2025 02:00 PM Notice End Date/Time: 12/01/2025 08:59 AM Required Response Indicator Description: 5-No response required Notice Text: Northern has scheduled the service outages that will affect operating capacity within the months of July 2025 through November 2025. 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): Ventura South (Group 735) Location: Northern's pipelines and compressor stations between Ogden, Iowa, and Farmington, Minnesota Project Description: Pipeline and compressor station maintenance Month: July 2025 through November 2025 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 August 2025 through September 2025. Allocation Group(s)/Point(s): Waterloo East (Group 773), Earlville East (Group 487), Galena East (Group 463) and Belleville East (Group 488) Location: Northern's pipelines and compressor stations between Waterloo, Iowa, and Belleville, Wisconsin Project Description: Pipeline and compressor station maintenance Month: July 2025 through September 2025 Direction of Flow: Delivery: Waterloo East (Group 773), Earlville East (Group 487), Galena East (Group 463) and Belleville East (Group488) Capacity Impact: Northern does not anticipate primary firm service will be impacted for Waterloo East (Group 773), Galena East (Group 463) and Earlville East (Group 487). Primary firm service will not be impacted for Belleville East (Group 488). Revision: Capacity impacts for Waterloo East (Group 773) have been updated for August 2025 and included for September 2025. Earlville East (Group 487) and Galena East (Group 463) have been included for September 2025. Market/Field Area Combined Allocation Group(s)/Point(s): Field to Demarc (Group 831) and Beatrice North (Group 832) Location: Northern's mainlines and compressor stations between Mullinville, Kansas, and Ogden, Iowa Project Description: Pipeline and compressor station maintenance Month: July 2025 through October 2025 Direction of Flow: Delivery: Field to Demarc (Group 831) and Beatrice North (Group 832) Capacity Impact: Northern does not anticipate primary firm service will be impacted for Beatrice North (Group 832) and Field to Demarc (Group 831). Revision: Capacity impacts for Field to Demarc (Group 831) and Beatrice North (Group 832) have been updated for August 2025 and September 2025. Field Area Allocation Group(s)/Point(s): Beaver North (Group 1025), Beaver C and Beaver North (Group 1080), Brownfield North (Group 1022), Pampa North (Group 1023) and Beaver C System (Group 31) Location: Northern's compressor stations and mainline between Florey, Texas, and Mullinville, Kansas Project Description: Station and pipeline maintenance Month: July 2025 through November 2025 Direction of Flow: Receipt: Beaver C System (Group 31) Delivery: Beaver North (Group 1025), Beaver C and Beaver North (Group 1080), Brownfield North (Group 1022) and Pampa North (Group 1023) Capacity Impact: Northern does not anticipate primary firm service will be impacted for Beaver C and Beaver North (Group 1080), Brownfield North (Group 1022) and Pampa North (Group 1023). Primary firm service will not be impacted for Beaver North (Group 1025) and Beaver C System (Group 31). Revision: Capacity impacts for Beaver North (Group 1025), Beaver C and Beaver North (Group 1080), Brownfield North (Group 1022), Pampa North (Group 1023) and Beaver C System (Group 31) have been included for September 2025 through November 2025. Northern does not anticipate primary firm service will be impacted for Pampa North (Group 1023) for July. Allocation Group(s)/Point(s): Sunray High (Group 32) and Sunray Low (Group 10) Location: Northern's compressor station in Sunray, Texas Project Description: Compressor station maintenance Months: July 2025 through September 2025 Direction of Flow: Receipt: Sunray High (Group 32) and Sunray Low (Group 10) Capacity Impact: Primary firm service will not be impacted for Sunray High (Group 32) and Sunray Low (Group 10). Revision: Capacity impacts for Sunray High (Group 32) and Sunray Low (Group 10) have been updated for September 2025. Allocation Group(s)/Point(s): Spraberry 12-inch (Group 601), Spraberry 16-inch (Group 1112) and Spraberry Station (Group 602) Location: Northern's compressor station in Midland, Texas Project Description: Station maintenance Month: July 2025 and August 2025 Direction of Flow: Delivery: Spraberry 12-inch (Group 601) and Spraberry 16-inch (Group 1112) Receipt: Spraberry Station (Group 602) Capacity Impact: Northern anticipates primary firm service will be impacted for Spraberry 12-inch (Group 601), Spraberry 16-inch (Group 1112) and Spraberry Station (Group 602). Revision: Capacity impacts for Spraberry Station (Group 602) have been included for September 2025. 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.