Raw data of hydrochemical and isotopic data of deep subpermafrost groundwater from borehole DH-GAP01 and DH-GAP04 and drilling lake waters, West Greenland (2009-2022)

The Greenland Analogue Project (GAP) investigated glacial processes and their influence on the long-term performance of deep geological repositories for spent nuclear fuel (Harper et al., 2016; Claesson Liljedahl et al., 2016). Field studies were conducted East of Kangerlussuaq, West Greenland, using the Greenland Ice Sheet as an analogue for future continental-scale ice sheets. As part of the GAP, two inclined bedrock boreholes (DH-GAP01 and DH-GAP04) were drilled near the ice sheet to study groundwater flow and analyze the chemical and isotopic composition of deep subpermafrost groundwater. Both boreholes were instrumented to facilitate water sampling and monitoring of temperature, pressure, and electrical conductivity. DH-GAP01 (drilled June 2009) is 222.5 m long, reaching a vertical depth of -191 m relative to the top of casing (TOC). The borehole was drilled beneath lake basin L26, about 20 m from the shoreline, and is equipped with a U-tube sampling system and one inflatable packer. Lake water from L26 was used as drilling fluid, and the borehole water sample intake is positioned at a depth of −138.57 m. DH-GAP04 (drilled June–July 2011) was drilled just by the ice sheet margin and is 687 m long, extending to a vertical depth of 650 m relative to TOC. The borehole is divided into three sections by two inflatable packers, with water sample intakes at depths of -511.43 m, -562.76 m, and -573.64 m; lake L25 water was used as drilling fluid. Water samples were collected from DH-GAP01 in 2009, 2010, 2011, 2014, and 2015, and from DH-GAP04 in 2011, 2013, 2014, 2015, and 2022. Samples from lake L25 and L26 were obtained during the same time span. This dataset provides a comprehensive compilation of the raw data from these sampling campaigns. The reconstructed data aimed to eliminate drilling and sampling induced disturbances are presented in (REF to the reconstructed dataset).