Social Distancing and Depth of Cover for the Megarule

Managing the requirements of phmsa gas transmission rule

Part of the U.S. MegaRule (also known as Updated Gas Rule or phmsa gas transmission rule) requires the integration of depth of cover survey results to help in identifying threats (section 192.917). A traditional survey requires a team deployed to walk the pipeline. A new approach uses ILI mapping data and surface level data to deliver reliable and repeatable depth of cover information without boots on the ground.

This webinar describes the key project steps associated with planning, data collection, data processing and the validation of results to determine depth of cover over an entire pipeline. Third-party interference is widely documented as being a major cause of damage to buried pipelines. In addition to routine surveillance, maintaining a minimum depth of cover is recognized as a key means of mitigation against third-party interference. In addition, increases in cover can result in settlement and excessive loading. We know that the depth of cover over pipelines can change with time.

Current techniques available for measuring depth of cover on buried pipes require significant in field effort. An innovative project has successfully demonstrated a methodology to measure depth of cover over an entire pipeline. This methodology combines ground elevation data with high resolution inertial measurement unit (IMU) data collected during in-line inspection allowing depth of cover to be calculated to an accuracy of ±6” (150mm).