# Software for Evaluating Pumping Tests on Real Wells
## 3 Data  
The data used for the analysis come from Serbia. The parameters of the aquifer and the well can be seen in Tables 1 and 2. The parameters obtained from the pumping test already include the anisotropy and inhomogeneity of the aquifer. In addition, most of the aquifers can be considered uniform with constant thickness.  
These data are limited by several uncertainties, which may occur because of several reasons: (1) structural-technical, (2) methodological, and (3) hydrogeological.  
1. In the first group especially, besides the construction design and use of material for collection wells, the type of connection and handling of pumping technology, including the drainage of water through the pipelines, one limiting factor is the initial phase of pumping, at which point the measurement can be affected by the dispersion of the moving elements of the submersible pumps. (This happens particularly in the case of high-capacity water supply wells in systems that are usually regulated by safety features, especially by frequency alternators.) As a result, there is a delay in reaching the originally set up pumping output. Another potential effect can be caused by the pressure resistance of the adjoining pipeline distribution system, including hydraulic shocks and the volume of the water in the discharge pipe (especially where non-return valves are absent).  
2. Methodological causes are related to the choice of the duration of the hydrodynamic tests conducted, as well as to adjustments and interpretation of measurement data,  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Name**} & **Transmissivity T** & **Storativity S** \\  & **(m\({}^{2}\)s\({}^{-1}\))** & **(-)** \\ \hline B1 & 0.00585 & 0.013 \\ B3 & 0.00385 & 0.0123 \\ B6 & 0.0036 & 0.00864 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Parameters of the aquifer.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Name**} & **rw** & **Well Depth** & **Well Storativity** \\  & **(m)** & **(m)** & **(-)** \\ \hline B1 & 0.149 & 87 & 996.6 \\ B3 & 0.1615 & 120 & 689.7 \\ B6 & 0.1615 & 110 & 2405.3 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Parameters of the well.  
which, in the case of horizontal inhomogeneity, tends to provide, with increasing time, increasing variation in the evaluation of hydraulic parameters.  
3. Hydrogeological causes of limitations and uncertainties of hydraulic parameters are mainly related to the vertical inhomogeneity of the rock environment when, in permeable rocks, the water flow follows the principle of dual porosity, which means it has a strong tendency to flow through preferential channels. Aquifers are usually divided into several individual tributaries, and they can also have different levels of underground water; moreover, the vertical direction of the water flow may also change. Then, if, during the pumping test, the groundwater level falls below that of one of the tributaries and the level of the latter also rises above the level of the saturated water flow, significant changes in the dynamics of measured levels occur, which also contribute to uncertainties in the interpretation of the resulting data.  
As far as the overall effects of the abovementioned limitations and uncertainties are concerned, the significance of errors of the sought-after parameters proportionally reflects the significance and size of the total input parameters.