De-watering
De-watering is the removal of water from a saturated medium caused by the pumping of groundwater from wells, or excavation into the medium allowing groundwater to drain freely to the void.  This may lead to groundwater inflow from surrounding areas, down a gradient created by the de-watering.

Flint
Very hard quartz that makes sparks.  GEOLOGY -  a very hard greyish-black fine-grained form of quartz that occurs widely as nodules and bands in chalk.

Geology
Structure of an area.  The study of the structure of the Earth or another planet, in particular its rocks, soil, and minerals, and its history and origins.

Geological Survey
An exploratory program directed to the examination of rock sediments obtained via boring or drilling by inspection of surface outcroppings.

Open cut
Mining by surface excavation.  Mining in which excavation work takes place on the surface and minerals are extracted by removing the top cover in strips.

Overburden
Unconsolidated surface material such as earth, sand and boulders, overlying and seperating the coal seams.

Piezometer
A piezometer is a non-pumping bore, generally of small diameter, that is used to measure the elevation of the water table or potentiometric surface.  A Piezometer generally has a short well screen through which water can enter.

Piezometric water level (or potentiometric surface)
Piezometric water level (or potentiometric surface) is the level to which water will rise in tightly cased wells.  If the head varies significantly with depth in the aquifer, then there may be more than one potentiometric surface.  The water table is a particular potentiometric surface for an unconfined aquifer.

Seismic
Relating to earthquakes.  Relating to or caused by an earthquake or earth tremor.

Subcrop
A subcrop is that part of a geological formation (eg a coal seam) that is close to the surface but is not outcropping.  It is usually under the soil profile or alluvial sediments.