PS07-001 - In the Matter of the Filing by Montana-Dakota Utilities Co., a Division of MDU Resources Group, Inc. for Approval of Waiver.
PS08-003 - In the Matter of the Complaint of Commission Pipeline Safety Staff against NorthWestern Energy Regarding Violations of the Federal Pipeline Safety Act.
PS09-001 - In the Matter of the Filing of the Investigation of the Natural Gas Incident of March 14, 2009, on Montana-Dakota Utilities Co.'s System in Rapid City, South Dakota.
PS09-002 - In the Matter of the Petition of the Commission Pipeline Safety Program Manager for Declaratory Ruling Regarding whether a Pipeline Operator's Documented Maximum Allowable Operating Pressure can Exceed the Limits in SDCL 49-41B-2.1 Without a Siting Permit.
PS09-003 - In the Matter of the Filing by NorthWestern Corporation d/b/a NorthWestern Energy for Approval of a Waiver of 49 C.F.R. Section 192.625(a).
PS09-004 - In the Matter of the Filing by the Commission Acting Pipeline Safety Program Manager Regarding South Dakota Intrastate Pipeline Company Compliance Issues.
PS09-005 – In the Matter of the Petition of the Commission Pipeline Safety Program Manager for a Declaratory Ruling Regarding Whether the Crooks Municipal Utilities Gas Line should be Classified as a Transmission or Distribution Line for Pipeline Safety Purposes.