A domestic wastewater has a pH of 7.5 and an alkalinity of 200 mg/L as CaCO3. At 25°C, estimate the resulting mixed wastewater pH if a flow rate of 5.00 million gallons per day (mgd) of the domestic wastewater encounters a spill of 5,000 gal/day of 10% HCl (specific gravity of the HCl solution = 1.09). Hint: it might help to use an alpha chart to understand the inorganic carbon (carbonate) species present at the initial and final pH).