Hydrologic and borehole geophysical data from the Perigo Mine site, Gilpin County Colorado

Hydrologic and geophysical data were collected in 2023-2025 near the Perigo Mine in Gilpin County, Colorado. Two boreholes (P9 and P10) were drilled in the fall of 2023. The drill site is located on a forested mountain hillslope near abandoned mining infrastructure at an elevation of about 2,970 meters. The boreholes were continuously cored using a wireline HQ-sized coring system through Quaternary soil, colluvium, and Precambrian-aged gneiss bedrock. In-situ injection-based hydraulic tests were performed during drilling while advancing using a single-packer apparatus in tandem with an in-line flow meter and interval pressure monitoring. Borehole geophysical logging was performed in the open holes. Each borehole was completed as four vertically discrete nested monitoring wells (P9A-D and P10A-D). Pressure transducers have been deployed in these wells along with pre-existing monitoring wells (P5 and P8) to monitor groundwater levels and temperature. Additionally, shallow soil moisture and temperature monitoring data were collected at 15 locations across the hillslope to better understand infiltration dynamics. This data release includes borehole location and well completion information from P9 and P10. The hydraulic test data directory contains in-situ packer test data collected during drilling and laboratory permeability/porosity results from selected core samples. The geophysical log directory contains borehole geophysical logs collected prior to well completion. The hydrologic monitoring data directory contains groundwater level and temperature data for fall 2023 to summer 2025. The soil moisture and temperature data directory contains shallow monitoring data for fall 2023-fall 2024.