$(30$ pts$)$ You are tasked with conducting an environmental assessment of a small river that is

proposed to receive body of effluent from a newly constructed wastewater treatment facility. The

width of this uniform river is $10ft(3m),$ depth is $1ft(0\mathrm{.}3m),$ slope is $0\mathrm{.}001,$ and the Manning

coefficient is $0\mathrm{.}03.$ To estimate travel times and dispersion coefficients, you inject $50g$ of dye at the

site of the proposed outfall. Because the river is too wide to easily distribute the dye evenly across

the channel, you dumped it in near the bank and figure that it will spread out soon enough.

a$)$ What is the discharge in this small river? $(5$ pts$)$

b$)$ What is the travel time from the outfall to a point $1km$ downstream? $(5pts$

c$)$ You set up a fluorometer and begin making concentration measurements $1km$ downstream. The

data show the following: $95\%$ lies between $800$ and $1200m$ at $t=2500sec.$ Estimate the

longitudinal dispersion coefficient for the reach of stream between the proposed outfall and the

meacurement location $(10$ nte$)$