Removing Floor Coal. Answer to Grosvenor methane exceedances?
It is impossible to have excess methane if the source of the methane has been removed
Inspector Gouldstone notes in July 2017 that LW101 face cutting profile has been altered and the floor coal is now being removed leaving roof coal.
The floor coal has been the source of Methane Inrushes in Development.
There are no further Methane HPI’s in Longwall 101 during 2017.
This situation changes when LW 102 commences and the mine reverts to leaving floor coal in the goaf
There are 29 Methane HPI’s on the Longwall in 2018.
Coincidence?
I do not think so.
Grosvenor Mine does not drain the floor coal below the Tonstein band
LWIOI is now at 1 1 CT, 690m from take off position. The cutting horizon has now been altered to take 600mm of floor dirt, extracting a height of 3.9m leaving a thicker coal roof (7 to 800mm). The longwall has been subject too a long period of down time with the damage incurred to the drift conveyor, 21 days commencing 9 May 2017 and then followed by AFC problems.
NEVER SEEN THE TERM “DIRT” USED IN UNDERGROUND COAL MINE BEFORE
WHAT WAS THE REASON CUTTING HORIZON WAS ALTERED?
INCREASED STRATA STABILITY OR TO REMOVE HIGH GAS FLOOR COAL?
