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w at - I l The data pitted on Figure 6 were used to evaluate tYe well performance. The drawdown in a pumped well consists of two components, the aquifer losses and the well losses. The aquifer losses are related to laminar flow conditions and vary linearly with the pumping rate. The well losses include. head loss which varies both linearly and non-linearly with well discharge rate. The linear well losses are generally related to aquifer damage during well construction. The non-linear (non-darcy) well losses are related to turbulent flow within the well screen, the discharge pipe and the terized by the formation. These two components can be charac following equation. S AQ + BOP where: AQ = linear head losses, - $Q = non-linear head lasses, s = drawdown at a given time, 0 - discharge rate, P e a discharge rate--dependent value between 1.5 and 3.5, and A an B are constants. P. value of 2 for P is commGnly accepted in this ewiation (Ramey, 1962), which yields the equation: s s AQ + B02, or dividing by Q, s/Q = A + B0 n., The latter equa�ton represents a straight line on an s/Q versus Q plot (Figure 6). it can be seen that the data points on Figure G fall on a linear trend. Using the approach outlined in Todd (19$0, '- p. 355), the data indicate a very significant non-darcy (non-linear) component of the drawdown. This non-linear component of the head loss includes some effects related to well slots (Krusemann and de rcidder, 1989). A further indication of the excessive well losses in '- ---- the well._-i is-Indicated recovery for the_. well MW5 after pumping was -- - - -- halted. This data shows extremely rapid_--recovery-(over 90*.. o -total-------- - -- -- - drawdown in the first iQ minutes) which is characteristic of wells with wellbore and near wellbore head losses due to turbulent flow. 3 L. weber Point PrepertP. 175, - 7 H2OR"791.TLP