$(1$ point$)$ We did a lot of work with material balances in water, and I mentioned that the same knowledge could be applied to air quality modeling. Here's an example:

You live $2km$ downwind of the refinery $($with the PM concentration you calculated from the plume equation$)$ and want to know how this new facility would affect you if you open your window. What would the concentration of PM in your house be if you left the windows open all day $($steady state$)$ if your house has a volume $2000m^3,$ you open windows such that the air entering and leaving your house is flowing at rate $0\mathrm{.}5\frac{m^3}{s},$ and the particles settle out of the air in a manner approximating first order decay with rate $k=\frac{0\mathrm{.}01}{s}?$

Hints: Before we had: $\frac{dM}{dt}=Q_i{C}_i-Q_o{C}_o+-kCV$

Eqn. $12-27$ states the same thing slightly differently

$V\frac{dC}{dt}=Q{C}_o+E-QC-kCV$

Outdoor concentration, $C_o=$

$\frac{g}{m^3}$

Assume there is no source

of PM inside your house

Which variable are we solving for: $.$

Relationship at steady state

Indoor PM Concentration:

$u\frac{g}{m^3}$

$(1$ point$)$ The investors noted that the facility is planned in the thousand$-$year floodplain. The loan to build the facility will take $30$ years to repay. What is the likelihood $($risk$)$ that the refinery will experience flood damage during this time?