The MBTA has until Monday to submit an updated plan for improving employee safety and preventing trains from striking workers after federal overseers, who still aren't satisfied with the T's staffing levels, deemed their initial proposal "insufficient."

Federal Transit Administration Chief Safety Officer Joe DeLorenzo on May 19 rejected a work plan from the T, writing that some of the measures it proposed to strengthen protections on the rail right of way targeted completion dates of "late 2023 and into 2024."

"Given the immediate risk to worker safety on the [right of way], FTA requires direct and focused actions," DeLorenzo wrote in a letter to MBTA General Manager Phil Eng.

DeLorenzo instructed MBTA officials to submit a new version of the work plan by June 5 with safety improvements that would take effect within 60 days. He also said the FTA would meet with T higher-ups "to identify and distinguish between the immediate actions that will be reviewed, approved, and tracked from the longer-term actions that MBTA may take."

DeLorenzo warned that if the MBTA fails to "appropriately revise" its insufficient work plan and comply with other requirements that federal safety officials outlined, the T will be prohibited from right-of-way access.

CBS Boston first reported Monday about the FTA's latest letter.

The FTA, which mandated a range of safety fixes at the T after an investigation last summer, in April flagged a series of "near misses" between subway trains and workers and ordered the transit agencies to improve employee safety.

MBTA spokesperson Lisa Battiston said Tuesday that the agency's first submission for an action plan to address right-of-way safety hazards "included both immediate and longer term actions to complete."

"The FTA has directed the MBTA to focus the workplan on the immediate actions only," Battiston said.

Battiston also pointed to ongoing efforts to expand the T workforce, a months-long effort that plays a critical role in both safety and service issues.

"The MBTA continues to also actively recruit for a number of positions in the Safety Department, and has briefed the FTA on a monthly basis on the status of department staffing," Battiston said. "The Safety Department continues to work closely with the Human Resources Department and a number of local universities with Safety programs to recruit qualified and talented candidates, among other hiring initiatives."

Building out the MBTA's workforce has been a frequently cited focus of Gov. Maura Healey and Eng, whom she installed as GM, but the hiring campaign has stumbled so far and remains well below the pace needed to achieve targets.

On the same day the FTA rejected the T's proposed right-of-way response, the federal agency also gave MBTA officials more time to improve internal safety monitoring tools and procedures as required by the 2022 investigation.

DeLorenzo approved the MBTA's request to restructure its response to one of the special directives, granting the T until Aug. 10 to resubmit a revised corrective action plan dealing with safety management systems and risk assessments. He wrote in a letter that the FTA's oversight "confirms the need to reassess actionable items and timelines to develop a more deliberate and targeted approach."

In that same document, federal safety officials aired concerns that the MBTA's safety department remains shorthanded. The FTA ordered the T to complete a staffing analysis of that office by June 25 and then develop "an urgent hiring plan and strategy."

"MBTA must expedite action to staff the Safety Department, including detailees and embedded contractors, if necessary, and conduct weekly staffing updates with FTA," DeLorenzo wrote. "We believe this focus on safety staffing will help alleviate the capacity challenges the MBTA is facing and enable the agency to better to address the safety issues identified in the Safety Management Inspection (SMI) and implement Safety Management Systems."

In addition to appointing Eng and replacing members of the MBTA's Board of Directors, Healey also tapped Patrick Lavin — who in 2019 contributed to an independent report slamming safety issues at the T — to a newly created role as the Department of Transportation's chief safety officer.