(WAVY) — Crews are continuing to make progress on the Hampton Roads Bridge-Tunnel this summer.

The Virginia Department of Transportation (VDOT) tells 10 On Your Side that after extensive work to the HRBT’s South Island, they were able to start reassembling Mary the Tunnel Boring Machine (TBM) on site.

Mary was named after Mary Winston Jackson. The name was chosen by Hampton Roads middle school students.

Measuring 430 feet long and 46 feet in diameter, Mary will be used to construct the new tunnels as part of the HRBT Expansion Project.

The HRBT Expansion Project aims to alleviate backups by adding two new tunnels and four additional lanes. The tunnels will be constructed using the bored tunnel approach, the first time that method has been used by VDOT. It is the largest highway project in Virginia history.

The tunnel boring process will take about a year.

Welding teams say they’ve completed putting Mary’s 46-foot-diameter tail skin together and are working to start welding the cutterhead. More than 170 containers of TBM components will be brought to the South Island for reassembly on the island surface or directly in the launch pit.

Work on the North Island ground improvements is ongoing as crews prepare to begin excavation activities of the receiving pit.

Bridge work continues as crews build the foundation of the new North Trestles.

In addition to the TBM, VDOT says the Expansion Project will also close the I-64 westbound West Bay Avenue off-ramp for several weeks during a specific time frame. Crews tell us the work will start Tuesday, June 21, and will be in place until July 8, 9 a.m. – 3 p.m.

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