Travis Johnson wrote:I have a gravel pit myself that is similar to what you describe, and while it is only 7 acres in size, yes I have made a little money off it over the years.
The calculations are really easy. You have to know how many acres your gravel pit covers, how deep the gravel bed is (called head), then subtract how deep the overburden is (topsoil) and get your number. Mine is 7 acres in size, and with an acre being 42,000 square feet, and the gravel bed being 32 feet deep, I have 9,362,000 cubic feet of gravel. Now a cubic yard is 27 cubic feet, so if we divide 9,362,000 by 27, we get 346,740 cubic yards. We still must subtract the overburden, and on mine it is a a foot deep, so I must subtract 301,000 cubic feet, or 11,148 cubic yards. So that means I have 335,592 cubic yards of gravel in the ground. However we need one more calculation. When you dig gravel out of the ground where it is tightly compressed, you get what engineers call "bucket swell" or swell factor. You said your gravel is good gravel, or clean gravel so it should be around 15%. For me, that would give me an additional 50,338 cubic yards of gravel for a grand total of 386,000 cubic yards of the stuff.
How did you determine size and depth?
