Problem $3(5$pts$)$: An industry is illegally discharging carbon tetrachloride $($CCl$4)$ into a river $($Qriver $=4$ m$3/$s and

Ariver $=10$ m$2).$ CCl$4$ acts as both a carcinogen and a non$-$carcinogen. At the point of discharge, CCl$4$ concentration

in the river is $1\mathrm{.}75$ mg$/$L$.$ There is a drinking water intake $($with no treatment for CCl$4)150$ miles downstream.

Assume CCl$4$ decays with a first$-$order rate constant k $=0\mathrm{.}55$ day$1.$ If a $70$ kg person drinks $2$ L of the water from

this intake per day, what is their lifetime cancer risk? Is the average daily dose from consuming this water greater

than the reference dose? Comment on if there is a concern to the person$$s health.

Hints:

$-$ you$$ll need to do a mass balance to find the concentration of CCl$4$ at the water intake

$-$ Q $=$ v$*$A $($Q $=$ flow rate, v $=$ velocity, A $=$ cross sectional area$)$