$1)$: A wastewater treatment plant discharges effluent into a nearby water body. The concentrations of nutrients in the effluent, and the corresponding eutrophication potential factors are given below:

Compound Concentration Eutrophication potential $($kg PO$4-$eq$)$

Ammonium Nitrogen $($NH$-$N$)10$ mg$/$l $0\mathrm{.}35$

Nitrate Nitrogen $($NO$-$N$)5$ mg$/$l $0\mathrm{.}1$

Orthophosphate Phosphorus $($PO$-$P$)8$ mg$/$l $1\mathrm{.}0$

Tasks:

$$ Calculate the eutrophication potential of the wastewater discharge for one year based on the given concentrations, if the plant discharges $700$ MGD $($million gallons per day$).$

$$ If the wastewater treatment plant implements a technology to reduce ammonium nitrogen concentrations by $50\%,$ recalculate the new eutrophication potential and discuss the potential improvement in water quality.

$$ Explain the potential environmental impact of the discharged contaminants on the receiving water body in terms of eutrophication, considering both the original and modified scenarios.

Problem $2$: Acid Rain Impact from Industrial Emissions

In an industrial area, a factory releases sulfur dioxide $($SO$2)$ and nitrogen dioxide $($NO$2)$ into the atmosphere. The release amounts are given in kilograms per hour:

Compound Release Amount $($kg$/$h$)$

Sulfur Dioxide $($SO$2)100$

Nitrogen Dioxide $($NO$2)80$

The local precipitation pattern indicates an average rainfall of $5$ mm per hour. Assume that the emitted gases dissolve in rainwater, forming sulfuric acid $($H$2$SO$4)$ from SO$2$ and nitric acid $($HNO$3)$ from NOx.

$$ Determine the amount of sulfuric acid $($H$2$SO$4)$ and nitric acid $($HNO$3)$ formed per hour, considering the chemical reactions:

$$ Calculate the pH of the resulting rainwater after the formation of sulfuric acid and nitric acid. Assume that both H$2$SO$4$ and HNO$3$ are fully dissociated in the rainwater.

$$ Explain the the potential impact of acid rain on local ecosystems, infrastructure, and water bodies.