A judge gave RTD approval late Tuesday to resume full testing of the long-delayed G-Line commuter train to Arvada and Wheat Ridge, a move that should help the transit agency get the 11-mile rail line open to the public more quickly.

Administrative law judge Robert Garvey ruled that testing of the G-Line trains could resume immediately, despite concerns about the line’s gate-crossing technology. Because of that issue, attendants will still have to monitor the crossings, and trains will be required to blow their horns upon the approach to each crossing.

Regional Transportation District spokesman Scott Reed said he didn’t know how long testing would take, saying only that it would probably last “months” and that approvals from both state and federal regulators would be needed before revenue service could begin.

RTD will issue a seven-day public notice this week, Reed said, after which testing will begin slowly before it ramps up to a frequency on par with full service — with trains running about 20 hours a day.

“We will stop and dwell at each station as if we were picking up and dropping off passengers,” he said.

He described Tuesday’s ruling as a “big step” because RTD was anticipating that any decision on G-Line testing would have to wait for a resolution to the crossing gate timing problems that RTD has been experiencing on the University of Colorado A-Line to the airport. The G-Line, which has undertaken limited testing this year, uses the same the same crossing gate technology as the A-Line.

Garvey, a judge with the state’s Public Utilities Commission, this month set a three-day hearing starting March 12 to consider the safety of at-grade crossings along both lines, though that hearing could be moved up to Feb. 15 if no objections are raised by freight rail lines that use the same corridor or several cities along the tracks.

Reed said full G-Line service wouldn’t commence until state regulators at the PUC sign off on RTD’s crossing gate technology, which has been plagued by software that closes the gates too early and leaves them down too long.

In September, the Federal Railroad Administration ruled that RTD’s design for the gates was adequate, but the PUC the same week refused to approve the design, citing safety concerns about potentially dangerous driver behavior caused by excessive wait times at the crossings.

The G-Line was originally set to open to the public in October 2016.

City leaders in Arvada and Wheat Ridge have lambasted the PUC for the delayed opening of the G-Line. The Arvada City Council signed off on a letter this fall that read “the continued, open-ended delay in commencing passenger service on the G-Line has real-world consequences for our communities and citizens.

“Our patience is at an end.”