It took 225 yards to fill the pipe almost 1 mile.  Grout came out of the vent valve and the contractor closed it off.  After about 30 minutes we were clean and leaving.  Went past the vent valve in the middle of a US Highway one mile away and looked like a river of grout.  All 3 lanes were 2 inches deep.  Next day when we set up to do the other half I found out that the valve had been broke off during back filling.  The second one went great.  My little Olin serves me well for these jobs.