$(4$pts$)$ During hydrologic river routing, as a flood wave passes through a river reach $($the

stretch of water visible between bends in a river or reservoir$),$ the peak of the outflow

hydrograph is usually

and

due to

and

$(2$ pts$)$ List the difference between the pores in the saturated zone and unsaturated zone.

$(2$pts$)$ GW exists in the unsaturated zone $($yes$/$no$,$ please circle$).$

$(2$ pts$)$ For an aquifer, the true velocity is $($greater$/$less$)$ than the Darcy's velocity. $($circle$)$

Why?

$(2$ pts$)$ An aquifer has a porosity of $0\mathrm{.}4,$ will you be able to extract $0\mathrm{.}4m^3$ of water per cubic

meters of this aquifer? Please circle $($Yes$/$no$).$

Why?

$.$

$(3$ pts$)$ When the retardation factor is $4,$ it means

$(\%)$ is dissolved in GW$,$ and

is sorbed to the aquifer solids.