I'm confused on what your using for your road. Is that the price for 4 inches of gravel to be put down with nothing on top?
Limestone gravel in my area of East Texas is $14 a ton a few months ago. I'm sure the price of fuel has increased that some. A full load on a belly dump has about 26 tones on it and will give me 4 plus inches of material ten feet wide for close to a hundred feet.
That's $364 per load. For 12 foot wide and inflation, I'd say $450 is a safe working number.
Do that for 2,700 feet and you are looking at $12,150 in rock.
Are you sure that price was for square feet and not liniear feet? Your looking at another $20,000 in labor.
Eddie