Step-test is a hydrogeological test, in which groundwater is pumped from borehole in several steps, at that time groundwater level is monitored. This kind of tests are used for determination of well performance, they also give information about screen type, their length and gravel pack. Step-tests must be done as a part of monitoring programme by clients in concession – concession holders of geothermal boreholes. Programme is definite in decree about concession of using thermal water. There are two versions to perform step-test, with consecutive steps or with intermittent steps. Purpose of master's thesis was to evaluate step-tests analysis of both versions, try to determine the most suitable version of step-test by the borehole aquifer type and also, to standardize step-tests terminology. In six days fieldwork we performed both versions of step-test in three boreholes, two of them was in fractured, while one was in porous aquifer. We monitored drawdown with level gauge. We organised the data from gauge in computer program Excel, in that we also made step-test analysis. This give us calculation of well efficiency, which is base for grade of borehole condition. We also compared step-test analysis results, at first results of both versions in each borehole, at second results of boreholes in fractured aquifer, and lastly this results we compared with results of porous aquifer borehole. For each borehole we define one of step-test versions as more suitable considering results. Based on this selection, we suggest a step-test with intermittent steps for fractured quifer, optional can be performed also step-test with consecutive steps. For porous aquifer we suggest an application of step-test with consecutive steps.
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