Hidrológiai Közlöny 1971 (51. évfolyam)

1. szám - Dr. Erdélyi Mihály: Hidrogeológiai tényezők hatása a felszínalatti vizek minőségére

Hidrológiai Közlöny 1971. 1. sz. 5 The influence of hydrogeological factors on the quality of sub-surface waters Dr. ERDÉLYI, MIHÁLY Department Head (Research Institute for Water Resources Development, Budapest) 1. The demands of communal, industrial and agricultural water supply keep growing rapidlv as regards both volume and quality. The growing pollution of subsurface waters and the rapidly increasing water quality requirement have prompted the quick development of two specialized branches of science, namely water technology and hvdrogeology. Chemistry forms an integrál part of both. Inereasing qualitative and quantitative water demands, the rational management and conservation of subsurface water resources, further a sound knowledge of rocks, as a factor in water technology call for information on the "history" of the water contained in rocks. A close cooperation of chemistry and hydrogeology, a "historical", viz. geological approach to water chemistry is liighly necessary when an answer is sought as to the origin, direction and velocity of flow., theavailable volume and quality of subsurface water. 2. The demand for research in water supply necessitating a close cooperation between hydraulics, hydrogeology, hydrodynamics and water chemistry is of such a recent date and of such a rapidly growing rate, that research cannot keep up with it. There are several causes for this problem. a) There was insufficient time, as yet, to suppress the static approach of water chemistry. The main problem is still concerned with the present state of subsurface waters rather than with the way in which it came to be thus, or with the changes and the causes thereof while being recovered. b) But time was alsó insufficient to develop research cooperation under a common aspect of experts in water chemistry, hydrodynamics and geologists, to attain better understanding of the natural processes in flowing subsurface waters. It is thus understandable that few publications reflect this aspect. There are not enough analytical data available to follow the history of water in certain major waterbearing formations with the invaluable help of water chemistry, though somé good examples are known. The nutnber of repeated analvses covering several years and concerning the water of the same spring (well) is alsó insufficient. The great volume of routine analyses, mainlv for public health purposes, is of limited use for this purpose. The same applies to the multitude of geochemical rock analyses, as only a few of these were prepared for hydrogeological aims. What little research work based on the new, dynamic approach has been completed is of major significance and indicates the soundness of complex research, but alsó that the coverage of this field is highly non-uniform. This does not concern the geographical aspects onlv. The lack of investigations concerning major hydro-geological units, but alsó their individual waterbearing formations is sorely felt. 3. In spite of noteworthy efforts in this field, due to the difficulties involved and to the slight chance of rapid success, few experts undertake complex research, especially where a new approach must alsó be adopted. Still, the main trend is towards a complex, régiónál research of subsurface waters covering major hydrogeological units, regardless of all initial difficulties. But alsó the institutions supporting research work could help guarantee the direction of development, if they were but ready to subordinate the many detail-subjects to the higher aim, and to carry out many routine investigations in a way to yield not only momentary benefits. Unfortunately, many modern, especially radiometric methods of research rarely advance bevond the technological level. The same applies — in part — to other mass-investigation methods. Many valuable data are stored without being used, there is no complex-aspect evaluation, which in a not very distant future, will be of interest to water management. 4. The papers submitted to the Conference are. 1. Dr. (]. Bidlá (Hungary): Investigations into the effect of silicate minerals and rocks on the chemical composition of water. 2. Gy. Gondos (Hungary): Relationship between the irón- and manganese compounds in water, and the mineralogical composition of the aquifer. '3. Dr. S. Karácsonyi — Dr. Gy. Scheuer (Hungary): The chemical characteristics of artesian waters, in the vicinity of Gyöngyös. 4. Dr. S. Karácsonyi — Dr. Gy. Scheuer (Hungary): Hydro-geography and hydro-chemical conditions controlling karstic waters at Eger. 5. Dr. T. Kecskés : Geological conditions and water quality. 6. Dr. A. Rónai (Hungary): The quality of subsurface waters in porous rocks. 1. G. Bidló described his studies to clear the qualitative and quantitative problems of soluble minerals in water, including potassium feldspar, almandine garnet, amphibole, turmaline minerals. In dissolving tests the duration and surface of exposure were identical. The results are indicated in tables. The dissolving of somé magmatic rocks was alsó studied, as water may alsó dissolve components which do not originate from the minerals investigated but from the vitreous content of the rock. Results are given of tests on a gránité from Velence and an andesite from Szob. The results relevant to the effect of clay minerals on groundwater had already been published in part, and reference to those is only made. His tests were of importance as they indicated the gaps in literature on the dissolving of somé