The council said two companies were applying to Mendip district council for permission to test drill for the gas, which is found in shale formed from deposits of mud, silt, clay and organic matter.
Staffordshire county council said the divers went into a culvert underneath the road and found blockages created by debris and a build up of silt and mud.
Work is slow along the 525-foot-wide route to Umm Qasr's grain elevator, where the Dredge Carolina chews up the mud with its 3, 000 horsepower cutter and suctions out the loosened silt.