Question $2$

Two observation wells are located in a glacial till. The shallow observation well indicates that the water table is at a depth of $1\mathrm{.}25$ m below ground surface. The ground surface elevation is $134\mathrm{.}13$ m $.$a$.$s$.$l$.$ The deeper observation well is screened at a depth of $6\mathrm{.}63$ m below top of casing $($TOC$).$ The elevation of the TOC is $134\mathrm{.}81$ m $.$a$.$s$.$l$.$ The water level in the deeper observation well is $4\mathrm{.}45$ below TOC.

$2$a$).$ Calculate the hydraulic gradient through the till layer and state the direction of flow $(5$ marks$).$

$2$b$).$ A sample of the till was taken during placement of the wells. The sample measures $5$ cm long and $10$ cm in diameter and was placed in a falling head permeameter. The head difference in the permeameter inlet tube $($area $\backslash (1\backslash$mathrm$\{$~cm$\}^\{2\}\backslash ))$ was observed to fall from a height of $100$ cm to $90$ cm in $9$ hours. Based on these results, calculate the hydraulic conductivity of the till. $(3$ marks$)$

$2$c$).$ Calculate the flow through the till. $(2$ marks$)$