## Material and Methods
### Characteristic of DRASTIC Parameters
#### 2.5.3 Aquifer Media  
The aquifer lithology is generally inhomogeneous. Slight variations are observed as regards thin till interlayers, weathered tilts or alluvial muds in sands. The aquifer lithology is represented by three main sediment types (Table 5): fluvial and glacofluvial sands (37% of the area), gravels and eolian sands (32%), and fine-grained sands with alluvial muds (26%). Their distribution is related to the extents of the individual generations of the Vistula River terraces, as well as to the near-surface deposits at the shallow groundwater table (Figure 4).  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Recharge Rate (mm/year)**} & \multirow{2}{*}{**Range of Parameter R**} & \multicolumn{3}{c}{**Area of Occurrence in Selected Years (km\({}^{2}\))**} \\ \cline{3-5}  & & **1999–2013** & **2003** & **2011** \\ \hline \(<\)\(-\)50 & 1 & 24.84 & 10.99 & 120.09 \\ \(-\)50–0 & 2 & 139.74 & 120.77 & 146.44 \\ 0–20 & 3 & 69.12 & 107.08 & 57.06 \\
20–40 & 4 & 77.47 & 290.69 & 55.69 \\
40–60 & 5 & 263.18 & 32.42 & 85.21 \\ \(>\)60 & 6 & & 12.39 & 109.86 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Net recharge and its range in selected years.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Groundwater Depth (m b.g.l.)**} & \multirow{2}{*}{**Range of Parameter D**} & \multicolumn{3}{c}{**Area of Occurrence in Selected Years (km\({}^{2}\))**} \\ \cline{3-5}  & & **1999–2013** & **2003** & **2011** \\ \hline \(<\)1 & 10 & 171.35 & 62.57 & 322.24 \\
1–3 & 9 & 266.34 & 277.26 & 176.21 \\
3–5 & 8 & 89.39 & 157.38 & 48.6 \\ \(>\)5 & 7 & 47.26 & 77.14 & 27.29 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Groundwater depth and its range in selected years.  
Figure 4: Parameter ranges of: (**a**) aquifer media (A); (**b**) soil media (S); (**c**) topography (T); (**d**) impact of vadose zone (I); (**e**) hydraulic conductivity (C).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameter** & **Characteristic** & **Range** &
\begin{tabular}{c} **Area of Occurrence** \\ **(km2)** \\ \end{tabular} \\ \hline \multirow{4}{*}{Aquifer media} & Surface water & 0 & 1.22 \\  & Fine sands, silty sands with till nays & 2 & 23.74 \\  & Fine sands with silty alluvial deposits & 3 & 148.70 \\ A & Sands with nilays of weathered tills & 4 & 36.10 \\  & River and fluvioglacial sands & 6 & 213.39 \\  & Gravels and eolian sands & 8 & 183.54 \\ \hline \multirow{4}{*}{Soil media} & Dusty, mineral-muck, silty alluvial soil & 5 & 166.07 \\  & Brown soil, black soil & 6 & 133.08 \\ \cline{1-1}  & Eolian-erosive soil & 7 & 32.24 \\ \cline{1-1}  & Silt-gley, peat soil, muck soil & 8 & 125.21 \\ \cline{1-1}  & Ground-gley, gley-podsolic, podsolic soil & 9 & 117.52 \\ \hline \multirow{4}{*}{Topography Slope (\%)} & \textgreater{}3.0 & 7.5 & 12.92 \\  & 2.5-3.0 & 8 & 8.81 \\ \cline{1-1}  & 2.0-2.5 & 8.5 & 17.91 \\ \cline{1-1}  & 1.5-2.0 & 9 & 23.57 \\ \cline{1-1}  & 1.0-1.5 & 9.5 & 63.78 \\ \cline{1-1}  & 0.0–1.0 & 10 & 447.47 \\ \hline \multirow{4}{*}{Impact of vadose zone I} & Surface water & 0 & 1.22 \\  & Laminated clays, tilts & 2 & 23.74 \\ \cline{1-1}  & Aggregate mud, silty alluvial deposits & 3 & 148.70 \\ \cline{1-1}  & Weather tills & 4 & 36.10 \\ \cline{1-1}  & River and fluvioglacial sands & 6 & 213.39 \\ \cline{1-1}  & Gravels, eolian sands & 8 & 183.54 \\ \hline \multirow{4}{*}{Hydraulic conductivity (m/day)} & \textless{}4 & 1 & 2.96 \\ \cline{1-1}  & 4-12 & 2 & 87.15 \\ \cline{1-1}  & 13–28 & 4 & 265.77 \\ \cline{1-1}  & 29–40 & 6 & 148.65 \\ \cline{1-1}  & 41–80 & 8 & 69.67 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Characteristics and range of A, S, T, I, C parameters.