It hasn’t been long since Tesla and SpaceX CEO Elon Musk unexpectedly announced he was getting into the tunnel boring business, but already the tech entrepreneur’s newest startup—the Boring Company—has gotten the go-ahead from the Hawthorne City Council to construct a test tunnel below the South Bay city.

In a 4-1 decision Tuesday, the council voted to allow the two-mile tunneling project to go forward.

Musk’s new company has already begun a smaller tunneling project below the SpaceX headquarters (also in Hawthorne), but the new tunnel will be longer and will allow for testing of the zero-emission transportation system that Musk has outlined in public presentations and cryptic tweets.

According to a report from city staffers, the tunnel will be constructed at a depth of between 22 and 44 feet below ground and will be about 12.5 feet wide on the inside. It will start beneath a parking lot owned by Space X and extend north before turning west around Crenshaw Boulevard and continuing below 120th Street to Hawthorne Boulevard.

Construction of the project is expected to take about five months, with the tunnel boring machine advancing about 60 feet per day—about the same speed as the tunneling machines used for Metro projects.

That much digging is going to produce a lot of dirt; the staff report notes that about 40 truckloads of material will be hauled away from the project site each day.

Brett Horton, senior director of facilities and construction at SpaceX, told the council Tuesday that, in spite of the project’s larger scope, residents of Hawthorne were unlikely to notice the construction.

“They won’t even know we’re there,” he said.

Once complete, the tunnel will be used for tests of Musk’s proposed subterranean transportation system, which the tech mogul says will carry cars and small shuttles on electric sleds at speeds up to 125 miles per hour.

It’s likely to be a long time before the technology becomes a viable alternative to LA traffic, as Musk has suggested, but Mayor Eric Garcetti has already expressed enthusiasm about the idea.