Water quality and flow of shallow groundwaters in the Sabae City, Fukui Prefecture was examined geochemically to apply them to build up a ground source heat pump system (GSHP).Groundwaters and river waters from 25 and 5 sample localities, respectively, were collected five times from June 2014 to July 2015 and analyzed for their chemical and isotopic (D and ¹⁸O) compositions. The results show that groundwaters are mainly of meteoric origin and that the δD and δ¹⁸O are -51.8 to -31.2‰ and -9.6 to -7.4‰, respectively, plotting between two meteoric precipitation lines (δD=8δ¹⁸O+17 in summer and δD=8δ¹⁸O+30 in winter).The chemical compositions of groundwaters in the eastern area are Ca²⁺–HCO₃^- type and those in the western area are Na⁺–HCO₃^- and Ca²⁺–HCO₃^- types. Several groundwaters in the study area have high Fe concentration up to 11 mg/L and are oversaturated with respect to Fe (OH) ₃. This means that cleaning of the heat exchange should be considered when open-type GSHP is used for room air conditioning.

Seventeen polycyclic aromatic hydrocarbons (PAHs) including sixteen United States Environmental Protection Agency (US-EPA) priority PAHs and benzo[e]pyrene were measured in the surface sediments collected from Ise Bay and Mikawa Bay, Japan. The total concentrations of PAHs (ΣPAH17) in the surface sediments varied from 97 to 415 ng/g-dry weight (ng/g-dw), with average value of 274 ng/g-dw. PAHs concentrations were comparable with those of other polluted coastal sites worldwide. Grading analysis of sediment samples was performed to determine grain size distribution characteristics from which median grain size, d₅₀ were calculated. There is a comparatively good correlation between the ΣPAH17 concentrations and d₅₀ for surface sediments. The isomeric ratios of PAHs (Ant/ (Ant+Phen), BaA/ (BaA+Chrys), IP/ (IP+BghiP), Fla/ (Fla+Pyr) ) were calculated to evaluate the possible PAHs emission sources in the sediments. The results of isomeric ratios indicated that fossil fuel and biomass combustion (pyrogenic sources) are major sources of the PAHs.