ARVADA, Colo. (CBS4)– The Regional Transportation District resumed testing on its Gold Line on Tuesday morning.

Once open, the commuter rail G Line will provide a direct route between downtown Denver’s Union Station to Wheat Ridge, passing through north Denver and Arvada.

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Testing on the line stopped in July 2017 after troubles with the A Line commuter rail to Denver International Airport caused a ripple effect that delayed the G Line’s opening.

Since July, RTD had only been allowed to test the line on a limited basis, up to once a week.

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The commuter rail will zoom through the station in old town Arvada without passengers. It’s one of eight stops on the highly anticipated new infrastructure.

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(credit: CBS)

Problems with the A Line’s crossing arms coming down too soon and staying down too long delayed testing of the GLine, which also uses “positive train control” technology.

The Public Utilities Commission (PUC) requires the full-on testing prior to allowing the line to open for public use.

RTD officials expect to open the G Line to passengers sometime this year.

(credit: CBS)

A re-hearing with the PUC is scheduled for mid-March, but could happen as early as February.

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The hearing, in part, will determine how quickly the G Line can get rolling.