Furthermore, portions of the aquifer network, particularly sections which underlie of metropolitan area of Binghamton in Broome County, New York, have been previously PR-171 molecular weight modeled (Coon et al., 1998, Randall, 1986, Wolcott and Coon, 2001, Yager, 1986 and Yager, 1993). Considering the extent to which gas ventures will most likely expand, it is desirable to extend the modeled areas to simulate the regional flow paths throughout Broome and Tioga counties. Within these counties there is a high degree of hydraulic connectivity between streams and the underlying aquifer (Randall, 1977, Wolcott and Coon,

2001 and Yager, 1993). Additionally, pumping induced recharge from streambed infiltration is significant in the study area (Kontis et al., 2004 and Randall, 2001). If municipal pumping rates increase, it becomes important to account for the possibility of added induced recharge. Conversely, groundwater discharge from stratified drift aquifers is the main source of base flow to streams during periods of drought (Randall, 2010). Increased groundwater pumping rates, therefore, would commonly reduce aquifer discharge to streams resulting in reduced stream flow (Randall et al., 1988), although a few broad valleys are drained only by small streams of local origin. The most significant groundwater flow this website occurs within the broad valley drift aquifers,

C-X-C chemokine receptor type 7 (CXCR-7) limited to the main glacial valleys. Major streams in this setting are parallel to the axes of the valley walls and would not help to constrain the hydrologic boundaries for groundwater flow. Because there are limited natural hydrologic features for use as boundary conditions, a two-dimensional watershed scale analytic element model (Jankovic and Barnes, 1999) was first constructed in Visual AEM (Craig and Matott, 2009) to develop boundary conditions for the localized area of interest

(Hunt et al., 1998). The scope of the first model encompasses the Upper Susquehanna River basin, including the valleys of Broome and Tioga counties. Using constant head boundary conditions from Visual AEM, a three-dimensional finite difference MODFLOW model (Harbaugh, 2005) was built to focus on the valleys of interest (Fig. 3). The extracted constant head boundaries were placed along the perimeter of the model extent and are significant in their simulation of upland recharge to the valley-fill aquifer network. Furthermore, the analytic element model was calibrated to real-time stream discharge measurements in order to approximate net regional groundwater recharge. The finite difference grid was set up in Groundwater Vistas Version 6 (Rumbaugh and Rumbaugh, 2011). The grid is comprised of 193 rows and 281 columns of 250 m × 250 m cells, with a total surface area of approximately 3390 km2 (Best, 2013).