In an effort to reduce the effects of HVL pipeline accidents, a notice of proposed rulemaking (43 FR 39402) was published on September 5, 1978, proposing a-requirement to install remotely controlled, closely spaced valves on new pipelines and certain existing pipelines. An amended notice of proposed rulemaking (44 FR 53187) was published on September 13, 1979, proposing two alternative schemes to locate valves on HVL pipelines. A public hearing was held on this matter on December 12,1979. Based on the information gained through these proceedings. and its own analysis and evaluation of that
information, the MTB has concluded that remotely controlled, closely spaced valves are not an effective means to reduce the effects of HVL pipeline ruptures. Therefore, the proposals to install valves on HVL pipelines are being withdrawn.