TSP Name: Northern Natural Gas Company TSP: 784158214 Notice ID: 109869 Notice Type: Planned Service Outage Subject: PLANNED SERVICE OUTAGES - JULY 2026 THROUGH NOVEMBER 2026 Location: MARKET AND FIELD AREA Critical: N Post Date/Time: 07/24/2026 10:46 AM Notice Status: Supersede Prior Notice: 109685 For Gas Day(s): 07/24/2026 - 11/30/2026 Notice Effective Date/Time: 07/24/2026 10:40 AM Notice End Date/Time: 12/01/2026 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 July 2026 through November 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/Field Area Combined Allocation Group(s)/Point(s): Field to Demarc (Group 831) and Beatrice North (Group 832) Location: Northern's pipelines and compressor stations located between the Mullinville, Kansas, and Ogden, Iowa, compressor stations Project Description: Compressor station and pipeline maintenance Month: July 2026 through November 2026 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 Field to Demarc (Group 831) and Beatrice North (Group 832). Revision: Capacity impacts for Field to Demarc (Group 831) and Beatrice North (Group 832) have been updated for August 2026 and September 2026. Market Area 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, Iowa Project Description: Compressor station and pipeline maintenance Month: July 2026 through October 2026 Direction of Flow: Delivery: Waterloo East (Group 773), Earlville East (Group 487), Galena East (Group 463) and Belleville East (Group 488) Capacity Impact: Northern does not anticipate primary firm service will be impacted for Waterloo East (Group 773) and Earlville East (Group 487). Primary firm service will not be impacted for Galena East (Group 463) and Belleville East (Group 488). Revision: Capacity impacts for Waterloo East (Group 773), Earlville East (Group 487), Galena East (Group 463) and Belleville East (Group 488) have been updated for August 2026 and September 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: September 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). Field Area Allocation Group(s)/Point(s): Beaver North ( Group 1025 ), Beaver C & Beaver North ( Group 1080 ), Brownfield North ( Group 1022 ), Pampa North ( Group 1023 ), Beaver C System ( Group 31 ) and Mitchell to Gaines ( Group 825 ) Location: Northern's compressor stations and pipeline between Florey, Texas, and Mullinville, Kansas Project Description: Compressor station and pipeline maintenance Month: July 2026 through September 2026 Direction of Flow: Delivery: Beaver North (Group 1025), Beaver C & Beaver North (Group 1080), Brownfield North (Group 1022) and Pampa North (Group 1023) Receipt: Beaver C System (Group 31) and Mitchell to Gaines (Group 825) Capacity Impact: Primary firm service will be impacted for Brownfield North (Group 1022) and Mitchell to Gaines (Group 825). Northern does not anticipate primary firm service will be impacted for Beaver C and Beaver System North (Group 1080) 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) have been updated for August 2026. Capacity impacts for Beaver North (Group 1025), Beaver C & Beaver System North (Group 1080), Brownfield North (Group 1022) and Pampa North (Group 1023) and Beaver C System (Group 31) have been included for September 2026. Allocation Group(s)/Point(s): El Paso/NNG Waha (POI 57100), Permian Highway Waha (POI 79489), GCX/NNG Waha (POI 79415), OneOK Westex Reeves (POI 152), Oasis/NNG Waha (POI 62148), Trans Pecos Hub (POI 79311), Agua Blanca Pecos Co (POI 79398), ETC Coyanosa (POI 78630), TW/NNG Estes Ward (POI 61334) and Vaquero Caymus Plant Pecos Co (POI 79303) Location: Northern's pipeline south of Kermit, Texas Project Description: Compressor station maintenance Month: August 2026 Direction of Flow: Delivery: El Paso/NNG Waha (POI 57100), Permian Highway Waha (POI 79489), GCX/NNG Waha (POI 79415), OneOK Westex Reeves (POI 152), Oasis/NNG Waha (POI 62148) and Trans Pecos Hub (POI 79311) Receipt: Oasis/NNG Waha (POI 62148), Trans Pecos Hub (POI 79311), Agua Blanca Pecos Co (POI 79398), ETC Coyanosa (POI 78630), TW/NNG Estes Ward (POI 61334) and Vaquero Caymus Plant Pecos Co (POI 79303) Capacity Impact: Primary firm service will be impacted for Permian Highway Waha (POI 79489), GCX/NNG Waha (POI 79415), OneOK Westex Reeves (POI 152), Oasis/NNG Waha (POI 62148), Trans Pecos Hub (POI 79311), Agua Blanca Pecos Co (POI 79398), TW/NNG Estes Ward (POI 61334) and Vaquero Caymus Plant Pecos Co (POI 79303). Northern does not anticipate primary firm service will be impacted for El Paso/NNG Waha (POI 57100). Primary firm service will not be impacted for ETC Coyanosa (POI 78630). Revision: Capacity impacts for Oasis/NNG Waha (POI 62148), Trans Pecos Hub (POI 79311), Agua Blanca Pecos Co (POI 79398), ETC Coyanosa (POI 78630), TW/NNG Estes Ward (POI 61334) and Vaquero Caymus Plant Pecos Co (POI 79303) have been included for August 2026. Allocation Group(s)/Point(s): PEPL/NNG Mullinville (POI 173) and ANR/NNG Greensburg (POI 179) Location: Northern's compressor station in Mullinville, Kansas Project Description: Compressor station maintenance Month: September 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). Allocation Group(s)/Point(s): Sunray Low ( Group 10 ) and Sunray High ( Group 32 ) Location: Northern's compressor station in Sunray, Texas Project Description: Compressor station and pipeline maintenance Month: July 2026 through September 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 August 2026 and included for September 2026. 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 Spraberry, Texas Project Description: Compressor station maintenance Month: July 2026 and September 2026 Direction of Flow: Delivery: Spraberry 12-inch (Group 601) and Spraberry 16-inch (Group 1112) Receipt: Spraberry Station (Group 602) Capacity Impact: Northern does not anticipate 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 12-inch (Group 601) and Spraberry Station (Group 602) have been included for September 2026. Allocation Group(s)/Point(s): Targa Monument Plant Lea Co (POI 6332) and Targa Eunice Plant (POI 6751) Location: Northern's pipeline south of Hobbs, New Mexico Project Description: Pipeline maintenance Month: September 2026 Direction of Flow: Receipt: Targa Monument Plant Lea Co (POI 6332) and Targa Eunice Plant (POI 6751) Capacity Impact: Northern anticipates primary firm service will be impacted for Targa Monument Plant Lea Co (POI 6332) and Targa Eunice Plant (POI 6751). Allocation Group(s)/Point(s): Enable Custer (BI) (POI 1907) Location: Northern's pipeline in Enable, Oklahoma Project Description: Pipeline maintenance Month: September 2026 Direction of Flow: Receipt: Enable Custer (BI) (POI 1907) Capacity Impact: Primary firm service will not be impacted for Enable Custer (BI) (POI 1907). 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.