You are working on a gas storage project where you need to inject natural gas into a depleted

gas reservoir for storage. The reservoir area is $500,000$ ft$2$

$,$ reservoir thickness is $90$ ft$,$ and the

reservoir porosity is about $32\%.$ Additionally, there is some immobile water with a saturation

of about $5\%$ of the total reservoir pore volume $($the water and gas are considered immiscible$).$

Based on the provided information, calculate the total number of moles of the stored gas at the

final reservoir pressure.

$\{$Hints: a$)$ only water and gas are present in the reservoir $($Sg$+$Sw$=1),$ b$)$ the provided graph is

assumed to be used for calculating the z$-$factor of the employed gas in the storage process,

c$)$ you can assume that the reservoir is cuboid$\}$

Initial Reservoir Pressure $($Pi$)=500$ psi

Final Reservoir Pressure $($Pf$)=2175$ psi

Reservoir Temperature $($T$)=212$F