Minnesota Office of Pipeline Safety Issues Safer Installation Guidelines Designed to Prevent Cross Boring
The Minnesota Department of Public Safety Office of Pipeline Safety (MNOPS) has issued new requirements, effective immediately, for installing gas lines and documenting the installation process. The new requirements were issued in an Alert Notice that was emailed to all 57 gas distribution operators in
MNOPS director Jerry Rosendahl says
The new installation and documentation requirements are intended to prevent “cross-boring,” where underground gas pipelines intersect and puncture privately owned sewer pipes. On Feb. 1, 2010, a cleaning contractor damaged a natural gas pipeline that had been inadvertently installed through a sewer service lateral on Villard Avenue in
MNOPS’ new requirements are the result of several months of work by MNOPS engineers, who reviewed industry white papers, discussed installation methods with pipeline operators and reviewed records of 155 instances in
Rosendahl says cross-boring can be eliminated without an open-trench installation process, and the Alert Notice outlines five safe alternatives for installers: Map and Record; Exposed Sewer; Sonde; Relative Elevation and Televising.
“Each trenchless gas line installation method we’ve approved requires very specific actions and documentation that the installation was carried out properly,” Rosendahl said. “These requirements will help prevent incidents such as the one that occurred in
Minnesota pipeline operators were informed in April of the basic contents of the Alert Notice, and MNOPS provided operators the opportunity to review it and offer input. Operators were also notified that the new requirements would be retroactive to Jan. 1, 2010. Installations made between Jan.1 and May 10 are required to have potentially intersecting sewer lines “televised” (inspected with an internal camera) by June 1.
Xcel Energy, owner of the Villard Avenue gas pipeline, is responding to all requests by homeowners and businesses to televise sewer lines within their