First of all I am filling in for my dad while he is away. Looking for clarification on how you would deal with this. Have a site where a 4" EMT-13,200 MV conduit is run over the surface of a landfill cap. There are several crossings along this run as it is about a mile long. At the crossings the EMT has a 6" PVC drain pipe sleeved over it. This was then covered with about 8" of processed gravel and than about 4" of loam. This is about a year old. the crossings are supposed to be for light duty equipment only. They have been using what appears to be about a 50 hp 4 wheel drive tractor with a brush hog type mower on the rear. It appears that the mower is cutting the crossing down as it goes over the crossing. Estimate that the equipment is around 4500 to 5000 pounds. in some locations there is only 2 to 3" of gravel over the PVC drain pipe.
Since this is not technically buried in a trench and not subject to commercial traffic how would you determine what the proper coverage would be for this crossing. My feeling would be to ramp up and over the conduit with a minimum of 4" of concrete.
Any help would be appreciated. gotta take care of dad while he is away.
nic