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Show Minimize Z = } t X awptt p+ X CT ( Qs t,-) X CF < Qpt k> g J k ( 2.10) where t is a time period index CFCQRtj) is the discounted cost of a release QRtf from reservoir i CF( QStj) is the discounted cost of a withdrawal QStj from a stream section j CF( QPtjc) is the discounted cost of a pumping Qfe from a well k. The cost from each source is a function of the amount of water withdrawn from that source. Stream and reservoir withdrawal costs include water treatment, pipe and pump system operation. Ground water withdrawal costs is the cost of operating the well system. Constraints 1) The amount of water withdrawn from all sources must satisfy demand, WDjt, for each time period t, for each demand area L X QRtu+ X Qs « ji+ X Qptki * ^ k t « = 1 •••• T- > = l •••• L ( 2 1 J> i j k 2) A minimum streamflow, SF^ nj, must be maintained in each time period, for each stream section. S Ftj- QS t j - Q s t S S Fminj t - l - T j - U ( 2.12) where SFtj is the stream flow in section j in month t and Qst is a factor used to account for the proportion of streamflow attributed to seepage, evaporation, etc., and may be related to the pumping in the area, using appropriate response matrices. 3) Hydraulic head, as measured by the Girinski potential, gmt, must be maintained at specified levels, gMINmt at points m, where drawdown is of concern. k 1 Smt" X X Qmklt QPtkl * S^ mt ' = l - T > m " l - M ^ k 1 where anj^ t are unit response matrix coefficients for pumping at well Q, k) 4) The pump capacity for a well, QPMAX^ j, may not be exceeded. t = 1 ... T QP^ < QPMAX^ k = 1 ... K f* ( 2- 14> 1 - 1 ... L } 16 |