There have been a number of tragic natural gas transmission line incidents lately, prompting a call for greater regulation. Among the responses is the Pipeline Transportation Safety Improvement Act of 2011 sponsored by Senator Lautenberg. Notably, it calls for a reconsideration of the exemption for natural gas gathering lines - despite the fact that the incidents in no way relate to gathering lines - and would require excavators, as well as the owners of underground facilities, to participate in One-Call programs.
It's still the beginning of the legislative process, but this is something to monitor.