Verticaltrx, the quarry is somewhere in the western part of the state. The stone yard, which gets bulk rock by train and crushes it here, is only 6 miles from my place. I was planning to get the crusher run from them directly, but my order was too small -- they only run bigger trucks, and I had concerns about knocking down a bigger pile in place and getting good spread/compaction. If I paid to have them split the load, the delivery charge would have been too high. So, I ended up buying from a local mulch place that sells rock and will do smaller truck loads (in fact, the max they can carry is 10 tons per trip). They get their materials from that same stone yard. I'll have to revisit pricing and sourcing when we do the full driveway and are looking at bigger loads.
crazyal, the VDOT rules are a bit scattered. For plastic or steel pipes, they recommend 12" cover, but note that 9" is acceptable for entrance culverts. How an entrance culvert differs from a culvert elsewhere in a driveway is not clear to me. They also have requirements for the bedding depth under the pipe, and amount of fill on the sides of the pipe. It scales with diameter. I agree with you on the 15" -- in fact, that's the minimum size that will handle a "10 year" storm event here, which is what they use to size ditches. 15" ID pipe is OK to handle runoff from an 8 acre watershed.
Right now the main road is private, but VDOT will be accepting it into their maintenance soon, so the developer insisted I follow the rules exactly. Some of the other lots have construction culverts, which are nothing more than a concrete pipe with fabric and #3 gravel over the top (ranging from 0" to 4" deep -- in most cases, traffic is driving over the pipe itself). How they will pass inspection is beyond me, unless VDOT simply doesn't care about construction entrances (I think the main requirement for a construction entrance is to have #3 gravel to clean mud off truck tires).
Most of the lots are shorter next to the road and won't have a long drive way, so construction traffic crosses the culvert and that's about it. Our lot is longer, so we'll need about 600 ft of driveway beyond the culvert just to get to the building site. I think we'll need to do the driveway first and have it fully cleared and surfaced before we get any construction traffic. I can't see having a 600 ft construction road that's all mud -- there's no way that's going to work out. I imagine we'll complete the driveway right up to near the building site, and put the fabric and #3 gravel up there to clean mud off tires before traffic hits the driveway. Probably add another run of fabric and #3 up near the road, perhaps on top of my culvert. That will help it take the added abuse and perhaps resist rutting from trucks turning off the road.
I do think I will widen the entrance radius a bit. Right now it's a 12' radius, per VDOT specs, but because this is a single lane road, you can't really make a wide turn. So if I add more radius to the driveway entrance, that will help.
