OCR Text |
Show Results with Non Linear Objective - Fixed Costs The third objective examined in this study considers the fixed costs of installing wells. There is the same general relationship between drawdown level and total pumpage ( Figure 2.10). Although the total amount of pumpage is the same, or a little larger, fewer wells are in use ( Table 2.1, Figures 2.11 and 2.12). A trade- off between the fixed cost of installing a well and the cost of pumping from the weD is thus demonstrated. Typically weUs at the center- line and alternate wells were not in the solution, when fixed costs were considered. The pump configurations are essentially symmetric about the site to be dewatered. This is consistent with the results obtained by Aguado & Remson ( 1980). The drawdown pattern is also symmetric and shows more variation in level than the other 2 cases. • QPMJLX* 1m3/ day * QPMAJU 2 • QPMAXs k * QPMAXs 6 11.5 11.6 11.7 11.8 11.9 Drawdown Level, netera 12.0 12.1 1 A © & Figure 2.10 Total Pumpage vs Minimum Drawdown required for non- linear objective function with fixed costs considered 26 |