The hydrogeology of a vertical fracture zone at 70 m depth at the access tunnel to the Äspö Hard Rock Laboratory was monitored over 3 a for hydrochemical changes that could be effected by construction of a deep repository for high-level nuclear waste. Tunnel construction dramatically disturbed the hydrogeological system, but this provided an opportunity to integrate hydrogeochemical and hydrological evaluation of the zone. The objective of this study was to evaluate hydrogeochemical evolution, groundwater flow and surface water intrusion during the experiment using an integrated approach of geochemical mass-balance calculations and numerical flow simulations.
Pitkänen, P., Löfman, J., Koskinen, L., Leino-Forsman, H., & Snellman, M. (1999). Application of mass-balance and flow simulation calculations to interpretation of mixing at Äspö, Sweden. Applied Geochemistry, 14(7), 893-905. https://doi.org/10.1016/S0883-2927(99)00025-6