Ionic composition and mineral equilibria of acidic groundwater on the west coast of Sweden
- Univ. of Uppsala (Sweden)
The groundwater chemistry of 14 shallow wells and 10 springs in Halland, southwest Sweden, and precipitation have been studied in trilinear diagrams. Ionic strength and saturation index (SI) for selected minerals have been calculated. Five springwaters have similar chemical composition to that of the precipitation, which indicates surficial and rapidly recharged water. The SI of the groundwaters is out of equilibrium (undersaturated) with respect to primary silicates such as mafic minerals, feldspar, K-mica and chlorite, but in equilibrium with solid SiO{sub 2} (quartz, cristobalite, or chalcedony). The SI shows oversaturation conditions for kaolinite, hydroxy-Al interlayered vermiculite, Na, K, Mg-beidellite, Mg-montmorillonite, and AB-montmorillonite. Concentrations of soluble Al and Si can be governed by Mg, Fe-beidellite, BF-montmorillonite, or Ca-montmorillonite at four springs, and by halloysite at two wells on the coastal plain. For these groundwaters, clay minerals may act as H{sup +} buffers and thus have an influence on pH and toxic Al, i.e., parameters affecting the drinking water quality and environment. The study shows that the soil catena are intensily weathered at the investigated sites. It is further concluded that neither cation exchange nor primary silicate weathering will keep up with buffering the acidic loads into the soils. A general prediction of groundwater quality is presented. 23 refs., 4 figs., 4 tabs.
- OSTI ID:
- 86438
- Journal Information:
- Environmental Geology and Water Sciences, Vol. 21, Issue 4; Other Information: PBD: Aug 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
Adsorption of fluoride by soils and minerals
Acidification, buffering, and salt effects in the unsaturated zone of a sandy aquifer, Klosterhede, Denmark