Aquifer: Soil layer in which groundwater is present

Bentonite: Drilling liquid, normally a clay mixture, that is being used for a HDD drilling. It prevents the drilling hole from collapsing and carries the soil that is drilled out.

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HDD Drilling: a Horiztonal directional drilling

Heterogenous: consisting of non uniform pieces

Homogeneous: consisting of pieces of uniform size

Perforation: The gaps in the filterpipe. Also called the filter crevice.

Regenerable: maintainable

Regenerate: to maintain

Rig: a drilling machine

Sand delivery: Entry of sand in a filter pipe

Screen: soil directly around a filter pipe

Spikes: subsidence in the level of underground water caused by vertical wells

TCO: Total Cost of Ownership

To develop: the final preparation of the soil around the filter pipe

Total cost of ownership: The total cost of a product during it’s entire lifecyclus. This includes e.g. development, construction, maintenance and destruction