GGU-SLUGTEST: Basic assumption

All of these models assume a transient, radial-symmetric flow in a confined aquifer.

The HVORSLEV (1951), BOUWER & RICE (1976) and BOUWER (1989) methods, on the other hand, employ Thiem's (THIEM, 1906) well equation for stationary flow. These methods are also suitable for use with a free groundwater level. HVORSLEV (1951) uses six different, empirically determined equations, employed according to well and aquifer geometry, for determining permeability.

The basic assumption is that the water level increases or decreases exponentially during a slug test. In contrast to all other authors, HVORSLEV (1951) differentiates between a horizontal, a vertical and a mean permeability. Where necessary, this allows due consideration of rock mass anisotropy.