The clean-up effort after the 6am crash took hours with Rural Fire Service (RFS) volunteers on scene mopping up leaking fuel.

Much of the spilled grain was salvaged by locals who lent a hand to sweep up the large load.

The cause of the crash is unknown with the truck driver taken by ambulance to Wagga Base Hospital for treatment for minor injuries.

Police were unable to interview him yesterday.

It is understood the semi was southbound on the Olympic Highway when it veered to the incorrect side of the road, down an embankment before crash- landing on its side.

Police said a passing motorist helped the injured driver from the cab and it was fortunate no other motorists were driving past when the truck crashed.

RFS volunteer John Baker said the fire crew managed to quickly contain the fuel leak.

"They managed to get in and turn off the fuel tanks before too much escaped. That made it pretty safe for them to get about mopping up," he said.

The highway remained closed in both directions for about four hours with traffic diversions in place.