DOT (US Department of Transportation) class location changes and their effect on pipeline operations and economics

Class location changes for natural gas pipelines, DOE (US Department of Transportation) standards established in 1979, have created some problems for gas transmission companies because the legislation retroactively imposes restrictions on the operation of some sections of existing pipelines. Wherever noncompliance with revised class locations occurs, companies must reduce the design capacity of the pipeline or rehabilitate it by replacement or hydrostatic testing. A comparison of the relative cost of each alternative with the economic life of the project in years and the minimum acceptable rate of return taken into account should determine the best course of action.