Two additional predictive transient simulations

were cond

Two additional predictive transient simulations

were conducted to investigate how water levels within the fen would be affected by reduced PD0332991 manufacturer groundwater pumping. These simulations focus on the high groundwater use summer months (June–September). The 2004 water year was treated as the base case (i.e., a representative dry year). The first predictive scenario considers a 50% reduction from the actual June–September 2004 pumping. This scenario would reflect a significant reduction in pumping, as suggested by NPS. The second scenario considers no groundwater pumping during this 4-month period. Winter water use in the Crane Flat area is minor and pumping occurred only 1–2 times per week. During September 2005, after a full summer season of daily pumping, water extraction produced distinct daily water level changes. Water levels in piezometer 49 had a sharp daily decline of up to 40 cm beginning around midnight, followed by a rapid rise in the morning

to near PLX3397 mw the previous day’s high (Fig. 2). Water level declines in well 10, which is a water table observation well, completed within the peat body, were up to 10 cm per day. Monitoring well 60, included as a reference well, is 360 m from the Crane Flat pumping well. Daily water table fluctuations at this well were not substantially affected by the pumping at Crane Flat (e.g., measured water levels did not respond to increased or decreased pumping intensity on September 12 and September 14–16, respectively). Rather, the smaller variation at well 60 is associated with evapotranspiration. The magnitude of water level decline was controlled by the duration of pumping,

distance to the pumping well, and whether the well/piezometer is open to the peat body or underlying gravel. Nights with longer duration pumping produced deeper and more sustained water level declines than those with Orotic acid shorter duration pumping. Pumping occurred for an extended period on the weekend of September 11–12 in 2005 and produced a very large drawdown (Fig. 2). Nights with short duration or no pumping resulted in a water level rise, for example on September 14–15, 2005 (Fig. 2). During the summer of 2004, following a very early melt of the snowpack (Table 1) the water table in Crane Flat declined more than 100 cm from mid-June to late-September (Fig. 3, Well 10). Similar deep declines also occurred in 2007, 2008, and 2009, all years with low or early peaking, and thus early melting, winter snowpack (Fig. 3, Table 1). In water years 2005, 2006 and 2010 larger winter snow packs persisted into April, resulting in water level declines of less than 50 cm under a similar summer pumping regime. In 2004 the water table was below the entire peat body by August, while in 2005 water levels remained within the peat body for the entire summer.

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