Fig. $5\mathrm{.}2$ Flow into a well with sloping water table $($after Wenzel, $1936)$

Example $5\mathrm{.}1$ A $30cm$ well fully penetrates a confined aquifer $30m$ deep. After a long period of pumping at a rate of $1,200lpm,$ the drawdowns in the wells at $20$ and $45m$ from the pumping well are found to be $2\mathrm{.}2$ and $1\mathrm{.}8m,$ respectively. Determine the transmissibility of the aquifer. What is the drawdown in the pumped well?

Solution From Eq$.(5\mathrm{.}6)$ it follows that

$Q=\frac{2\mathrm{.}72T(s_1-s_2)}{lo{g}_{10}(\frac{r_2}{r_1})}$