A review of slug tests analysis on South African aquifers in potential yield and transmissivity estimations

Abstract

Study RegionThis research paper focuses on the application of slug test on South African fractured rock aquifers and the applicability of the test to provide potential aquifer hydraulics. The region of the study was Petrusburg which is situated in the Free State Province, South Africa. Study FocusThe aim of the study was to develop a methodology to relate slug tests to a potential yield estimation, therefore investigating and reviewing the applicability and accuracy of the slug test methodology in South Africa, applied on fractured rock aquifers as established in 1995 (Vivier et al., 1995). The aim was achieved by reviewing the methodology applied for slug tests that are related to potential yield estimations (Vivier et al., 1995); identifying the limitations of slug tests; investigating the possibility to update the potential yield estimation method of 1995; and, by investigating the possibility to relate slug tests, by implementing two-dimensional modelling, to potential yield and transmissivity estimations. New hydrological insight in the RegionIt was determined that slug tests can no longer be used to relate the recovery time for 90% of the initial static water level (s) to the potential yield (L/s) as an exact value but can rather be seen as an estimation tool to determine what potential yield in terms of ranges. The investigation revealed that the use of simple, homogenous models can be used to determine the possible transmissivity for slug tests and relate that transmissivity to a potential yield (L/s). Note that this is not an absolute and is subject to limitations.