The decedent, an o/operator, was located behind the truck, behind the raised dump trailer when a load of sand dumped from the trailer. The decedent was buried in the sand. Mgmt became aware of the missing driver at approx. 10:45 am and promptly began a search. EEs began digging in the pile of sand behind the decedent's truck and the decedent was discovered at approx 11:43 am.