The Trump administration's latest version of pipeline safety legislation, released Monday, addresses some of the problems that caused or contributed to last year's gas fires and explosions in the Merrimack Valley.

The bill submitted to Congress would require utilities to use redundant systems to prevent over-pressurization, which caused last September's disaster. It would also increase the requirements for construction plans — Columbia Gas was using plans that were missing crucial information, which could have prevented the over-pressurization of the gas pipelines.

But U.S. Sen. Ed Markey of Massachusetts said in a statement that while the bill "includes some commonsense provisions that would help avoid what happened in [the] Merrimack Valley," it "fails to address all the key issues around safety and accountability.”

The legislation is renewed every three to four years, according to Bobby Fraser, director of governmental, international, and public affairs for the Pipeline and Hazardous Materials Safety Administration (PHMSA), which is part of the federal Department of Transportation.

"One of the problems with what the situation in the Merrimack Valley was that [Columbia Gas] didn't have clear, concise standards that they needed to adhere to," Fraser told WGBH News. "And we need companies to have that when they're replacing pipelines. So that's something that we do have in the bill and we want to work together with the leaders in the Senate and House to work on that."

Read more: Merrimack Valley Communities Hit By Gas Blasts Get $80M In Settlement With Columbia Gas

Fraser said it's common practice for PHMSA to look at major pipeline accidents and try to address them in re-authorization legislation. In this case, he says the agency is trying to anticipate both findings coming from the National Transportation and Safety Board's ongoing investigation of the Merrimack Valley disaster and what leaders in Congress may want to see in the re-authorization legislation.

Markey, along with Sen. Elizabeth Warren and Rep. Lori Trahan, introduced a pipeline safety bill in April named for Leonel Rondon, the young man who was killed by falling debris from a house that exploded in the disaster. Dozens more were injured, and thousands forced from their homes for months after over-pressurization flooded homes with gas that ignited.

The Leonel Rondon Pipeline Safety Act would, among other things, require the use of licensed professional engineers to approve significant system changes.

Last November, the NTSB issued urgent safety recommendations while investigating the gas explosions, saying that review by a professional engineer could have prevented the September 13 accident, since Columbia Gas' work plans were missing crucial information about pressure sensors.

Read more: New President Of Columbia Gas Says First Goal Is To Regain Trust

Massachusetts has since passed a law that requires licensed professional engineers to sign off on all gas company construction plans, though most states do not have such requirements, and PHMSA's proposal doesn't address the issue.

Markey wants to incorporate elements of the safety bill he's co-sponsoring into the PHMSA reauthorization legislation, including better on-site monitoring of gas pressure so that employees could quickly shut it off in an emergency. Markey's bill would also raise civil penalty limits, which his office said is to "better deter wrongdoing and reflect the costs that safety failures can have on communities."

Fraser said another part of PHMSA's proposal to Congress would lay out more detailed requirements for gas companies when they're replacing aging pipelines as Columbia Gas was in the Merrimack Valley.

"The ironic thing is that all the pipeline safety advocates and state and federal level governments are encouraging companies and local pipeline operators to replace those aged distribution lines," Fraser said. "But you've got to do it right ... in this case they just did it horribly wrong."

Columbia Gas is facing two wrongful death lawsuits and a separate class action lawsuit related to the Merrimack Valley gas fires.