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When the unexpected crossover solution began reporting to Phase 1 action was taken <br />immediately to redistribute flows on the surface. However, because of the depth of the VLF <br />several days are required for changes to propagate through the system and, hence, the elevated <br />inflow continued for much of May, subsiding on approximately the 24th. In addition to efforts on <br />the pad surface the level in Phase 2 was carefully managed to maintain the lowest volumes <br />possible providing maximum insurance against any unplanned discharge events. Figure 4 shows <br />the pond flows and levels for the Phase 2 PSSA. From the figure it is clear that the level reached <br />a maximum of 25.9' at the caisson and was always below what could be measured by the <br />independent monitoring well. (N.B. — The probe registers a value of 31' when the level cannot be <br />detected.) At the relative influent and effluent flow rates, this level translates to a buffer of <br />upwards of 20 days before the PSSA reaches capacity. The level Phase 2 was dropped whenever <br />possible to provide even more safeguard. <br />8,000 <br />7,000 <br />6,000 <br />5,000 <br />a <br />on <br />4,000 <br />A <br />cc <br />p 3,000 <br />LL <br />2,000 <br />Phase 2 Flows <br />—�Flow Out (Meas.) } Flow In(Cai, )—Appked(ti"e,is.) • (,aiwul �Vcll <br />r 80 <br />70 <br />60 <br />50 <br />40 <br />0 <br />30 J <br />20 <br />`W-,* <br />•900#sN"•0 a ��N �� ♦N <br />1,000 10 <br />0 0 <br />0" tied L'i �tY 1 yp Lti Lg ti yti �� by 1 <br />Figure 4 — Flows and levels for the Phase 2 PSSA. Dashed and solid lines indicate the 80% and <br />maximum capacity levels, respectively. Note — the monitoring well terminates at an ultimate <br />depth 31' above the PSSA floor. Levels below 31' cannot be measured outside the pump <br />caissons. <br />As shown in Figure 2, the level in the Phase 1 PSSA has dropped below the 80% mark and is <br />trending down further. This is a result of the efforts to redistribute flow on the surface of the <br />VLF and to decrease the overall volume of solution through evaporation. Misters were installed <br />on several of the lines on the VLF to increase the evaporation rate as a temporary aid to help <br />manage the overall water balance. Additionally, the new Phase 4 pumps and pipeline were <br />commissioned in June. Work is currently underway to bring additional areas on Phase 4 under <br />leach to redistribute flows further decreasing flows to Phases 1 and 5. This process will take <br />