A Final Order issued by PHMSA clarifies how operators of natural gas pipelines should apply the Class Location rule that includes within the definition of a Class 3 area certain “frequently used buildings or well defined outside areas.” Design, construction, testing and operating pressure standards for natural gas pipelines vary by Class Location, with criteria ranging from Class 1 through Class 4 criteria. Generally, a Class Location increases with increased density of buildings intended for human occupancy, as measured 220 yards to either side of, and along, the pipeline (a “Class Location Unit”). A Class 3 area is defined as “any Class Location Unit that has 46 or more buildings intended for human occupancy,” or any area where the pipeline lies within 100 yards of “a well-defined outside area” (such as a playground, recreation area or other place of public assembly), “that is occupied by 20 or more persons on at least 5 days a week for 10 weeks in any 12 month period.” 49 C.F.R. Part 192.5(b)(3)(ii). The intent of this rule was to include certain frequently used areas, even if not densely populated, within the scope of protection assigned to more urban areas.

In the El Paso decision, the Agency agreed that Class 3 designations based on “well defined outside areas” (not building density) should extend only 100 yards along a pipeline (not 220 yards as asserted by the Region). This decision affects Class Locations in rural or less developed areas, which could include sports playing fields, running tracks near schools, etc. The Agency’s Final Order in this matter should help operators treat such areas consistently, which are increasingly common due to developments and urban-rural interface.