One day before Saturday’s deadline, the Regional Transportation District has finalized the plan it submitted to the Federal Railroad Administration that is meant to address how it is fixing the known issues with the timing of the A Line’s crossing gates.

RTD spokesperson Laurie Huff said a copy of it will be available to the public online starting Monday.

In a news release, RTD said the plan aims to resolve the crossing gate issues within a year. 

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This comes after the FRA threatened to shut down the A Line between Union Station and Denver International Airport, calling RTD’s failure to improve the timing of the crossing gates “unacceptable” in a letter dated Nov. 15.

When federal regulators visited Denver in August to examine the gates along the A Line and the B Line – which runs from Union Station to Westminster -- the gates did not pass their tests 63 out of 540 times, the letter said.

The timing of the crossing at Holly and Monaco were the most problematic, the FRA said. These gates didn’t meet standards 20 percent to 30 percent of the time, according to the letter.

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These aren’t new issues.

The timing of the crossing gates for the A Line have been a problem since it started running in 2016, but RTD was allowed to run the trains with attendants manning the crossings.

Those “flaggers” were allowed to leave their posts earlier this year, but they came back to three A Line crossings and one on the B Line in August because of continued concerns about those gates.

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The FRA granted the A and B Lines a five-year waiver in September 2017, so it’s not clear why regulators ran tests one year into it.

“This level of noncompliance with the conditions of the waiver is unacceptable,” the Nov. 15 letter said. “If RTD fails to submit an acceptable action plan within 30 days of RTD's receipt of this letter, FRA will have no choice but to consider other actions as appropriate, potentially including enhanced enforcement, modification of the existing waiver — including by imposing additional conditions as necessary for rail safety and/or reducing the duration of the waiver — or revoking the waiver.”

The FRA also wrote that because of the concerns over crossing gates, it cannot allow the G Line, which will run from Denver to Arvada and Wheat Ridge, to begin operating. RTD expected the G Line to open in October 2016.

The A, B and G Lines were the first trains in the country to begin running with these gate-control and operating systems.

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