Getting rid of static charge in fuel tanks
The process of grounding the tanker is still carried out. The first thing they do before unloading the fuel is ground the tanker to earth in order to discharge all the static charge through a safe path. This process of governed by various standards of operation. An example of the grounding setup looks like the following: 



Source:
http://www.newson-gale.com/knowledgebase/ettg22/tank_truck_grounding_1.asp