Sets and Indices
k	Contaminant
r	Unit source
i	Unit intercept
IU	Set of intercept unit
SU	Set of source unit
Parameters
AR	Annualized factor
α	Cost exponent for intercept unit
H	Hours of plant operation per year
CIU	Investment cost of treatment unit
$C{U}_{fw}$	Cost of freshwater
$FS{U}_r^{out}$	mass flowrate of outlet stream from source unit r
$xU{S}_{r,k}^{out}$	concentration of contaminant k in outlet stream from source unit r
$R_{i,k}$	% removal of contaminant k in intercept unit t
$xU{D}_{d,j}^{in,max}$	maximum concentration of contaminant k in inlet stream into demand unit d
Continuous Variables
$FS{I}_{r,i}$	mass flowrate of stream from unit source r to intercept unit I
$FU{I}_i^{inlet}$	mass flowrate of inlet stream intercept unit I
$FU{I}_i^{out}$	mass flowrate of outlet stream from intercept unit I
$FS{I}_{r,i}$	mass flowrate of water stream from source unit r to treatment unit i
$xI{U}_{i,k}^{inlet}$	concentration of contaminant k in inlet stream into intercept unit
$xU{I}_{i,k}^{out}$	concentration of contaminant k in outlet stream from intercept unit I
$FI{D}_{i,d}$	mass flowrate of stream from unit intercept i to demand unit d
$FI{M}_i$	mass flowrate of water stream from intercept unit i to final mixer
$xSI{U}_{i,k}^{out}$	concentration of contaminant k in outlet stream from splitter treatment unit I
$FU{D}^{inlet}{}_d$	mass flowrate of inlet water stream in deposit unit d
$F_{freshwater}$	mass flowrate of freshwater
$FS{D}_{r,d}$	mass flowrate of water stream from source unit r to deposit unit d
$xSU{D}_{d,k}^{in}$	concentration of contaminant k in inlet stream into deposit unit d
$xU{S}_{r,k}^{out}$	concentration of contaminant k in outlet stream from source unit r
$xU{D}_{d,k}^{in,min}$	minimum concentration of contaminant k in inlet stream into demand unit d