(heavy machinery)

[Voiceover] Underneath Grand Central Terminal,

there's another terminal being created

in New York City.

The terminal itself consists of two underground caverns

that are 60 feet high, 60 feet wide,

and 1200 feet long.

A project length underground

as it begins in Sunnyside Yard,

and runs underneath Long Island City

and down to the termination point at 37th Street

is approximately three miles.

The rock that makes up Manhattan

is primarily Manhattan schist,

and there's a lot of other different types

of rock mixed in with that.

There's quartz, there's pegmatite, there's amphibolite.

A lot of these rocks are like 20,000 psi and stronger.

That's why in New York you can build such huge skyscrapers,

and such deep tunnels,

because the rock is such a high quality.

It'll support itself and everything else above it

and below it.

Family history in the underground industry

is back to my grandfather,

and then my father followed in his footsteps

and he was in the underground,

so I just kinda gravitated towards that.

(footsteps)

I really think about

what it's gonna look like when it's done.

The fact that it's gonna take another five or six years

to get to the point where you can look back and say

wow, I was part of this.

If I were to leave now, it would just be kinda the end

of another job.

But if you get to stay to the finish,

you can see the finished product.

When people are using it,

and it does what it's supposed to do,

then that's the best part of it.