NEB confirms that no standards exist for maintenance of depth of cover over pipelines after installation

The National Energy Board ("NEB") has just released its report into its investigation of various whistleblower allegations made against TransCanada PipeLines Limited (read the report here).  I haven't read through the report in full, but I was drawn to the section dealing with inadequate cover over a pipeline.  In its observations, the NEB notes that:

"Other than during the design and initial installation of the pipeline, CSA does not address requirements for maintaining the depth of cover during the life of the pipeline.  In a general sense, OPR section 6.5(1)(e) requires companies to: identify the hazards and potential hazards; assess the risk associated with those hazards; and implement controls to prevent, manage and mitigate those hazards.  TransCanada has recognized the low depth of cover as a hazard, has assessed the consequence of a hazard to be low because the site was in an unused, fenced in pasture area and has mitigated the risk by installing fencing to secure the site."

In other words, there is no regulation in place for NEB-regulated pipelines with respect to the depth of cover that must be maintained over a pipeline.  Once a pipe is installed, it is left to the company to determine what depth must be maintained over a pipeline to avoid potential hazards.  For people who have read through the CSA Standards applicable to pipelines (which requires an expensive licence), this gap in regulations was obvious.  In some cases, landowner groups have successfully negotiated agreements with pipeline companies requiring maintenance of depth of cover over pipelines to a specific minimum depth and requiring the payment of compensation where restrictions on land use are imposed.  But what about everyone else with a pipeline on their lands?

Isn't depth of cover an important enough component of pipeline safety that it should be the subject of specific prescriptive regulations?