There are about 9,000 aggregate operations
in the U.S., putting one close to every major city. We use about 3
billion tons of crushed stone, sand, and gravel every yearnearly
half the Earth materials mined in this country. Today, the concrete
foundations and facades of homes, schools, offices, and stores are built
with quarried materials. An average new house in the U.S. is constructed
with about 400 tons of sand, gravel, and crushed stone (mostly
Anatomy of a Road
Woman: Every man woman and child uses about 10 tons of it each year.
Man: Youre joking? Ten tons…of rocks? How is that even remotely possible?
Woman: Well, for starters, each lane of this interstate consumes an
astonishing 38,000 tons of rock per mile. Your average pick up truck
carries about a ton. Thats 38,000 pick up trucks of rock that are used
to make each mile of highway. The average home uses 400 tons of gravel
Man: Millions of tons of stone are used in farming each year as lime.
Woman: Or in toothpaste, glass, runways, railroad beds or pharmaceuticals.
Its all aggregate.
Man: Whats an aggregate?
Woman: Its this…rock in all its forms; sand, gravel and crushed
stone, like granite and limestone.
Man: Where do they get it all from? I mean do they just dig it up
Woman: Thats exactly what they do - dig it up. More accurately, some
of it is mined and some is dredged from under water and from other areas
where there are sand and gravel deposits. And for some, they have to blow
it up. Its actually a series of small, precisely set and tightly controlled
mini-blasts just microseconds apart. Fracturing rock is a very precise,
exacting science. The result is a highly regulated and controlled fracturing
process. The actual noise or vibration is carefully monitored. And is
usually less than the noise of a highway.