©Geol. Bundesanstalt, Wien; download unter www.geologie.ac.at ©Geol. Bundesanstalt, Wien; download unter www.geologie.ac.at ©Geol. Bundesanstalt, Wien; download unter www.geologie.ac.at Introduction to complete the text of the Austrian part of the Explanatory Note. Therefore there are some differences in the accuracy Compilation of the environmental hazard maps has of the map and some gaps in the text, both concerning the become an ordinary practice all over the world during the Austrian part. past ten years. Nevertheless, these maps are prepared according to various methodologies which reflect different Natural hazards approaches concerning their make-up and content (ALEOTTI & CHOWDHURY 1999). There is still a lack of uni- Pollution sensitivity form guidelines defining their compilation. The Map of General aspects Environmental Geohazards (MEG) of the DANREG region at a scale of 1:100 000 represents one type of geo- The sensitivity of the environment (rocks and ground- hazard map which has been elaborated by a trilateral team water) to pollution is delineated in the MEG by the five of the DANREG programme (Slovakia, Hungary and danger categories: Austria). The original map name “Environmental Risks 1. very high (permeable rocks on the surface), Map” has been changed with agreement of the national 2. high (permeable rocks on the surface covered by project leaders in order to respect the definition of con- thin aquiclude or less permeable rocks), cepts like hazard and risk (DEARMAN 1991). 3. moderate (permeable rocks covered by thick MEG is a complex and multi-purpose map supple- aquiclude or less permeable rocks covered by thin mented by a legend and an explanatory text. Coloured pla- aquiclude or rocks of medium permeability), nar, linear and point symbols are used to display relevant 4. low (rocks of medium permeability covered by thick geological hazards of the Danube region: aquiclude or low permeable rocks covered by thin Natural hazards: aquiclude or without cover), — pollution sensitivity, 5. very low (low permeable rocks covered by thick — hydrological and hydrogeological phenomena, aquiclude or aquiclude on the surface). — mass movements, Each category is represented by different colour in the — tectonics, MEG. The borders of main lithologies (karstic, volcanic, — seismicity, granitic and metamorphic rocks) are also depicted in — erosion and accumulation, coloured areas. — karst and hydrocompaction. Two different methods were used for the evaluation of Anthropogenic hazards: hydraulic parameters of rocks in the DANREG region. In — deposition (replenishment, waste), spite of this fact the results of the assessment of environ- — mines, mental pollution sensitivity are very similar for the territo- — subsidence. ry of each country. It means that to the similar or the same The philosophy of the MEG, e.g. the means of hazard rocks the same degree of sensitivity has been attributed on delineation and evaluation integrate the opinions of spe- the territory of each country. cialists from each country engaged in the project. Pollution sensitivity assessment in the Slovak territory is Differences in the assessment of some hazards (pollution based on the 4–5 degree semi-quantitative classification of sensitivity of rock environment, waste) resulted from parameters like uppermost aquifer transmissivity, aquiclude using unbalanced parameters or to inaccessibility of thickness and depth as well as on the qualitative classifica- important data. The selection of hazards, the manner of tion of permeability type of rock body down to 20 m depth. their assessment and display reflect the geological setting The aquiclude is defined by its hydraulic conductivity being of the region and its hydrogeological and engineering geo- k £ 10–7 m/s–1. Different types of the structural arrange- logical conditions. The accuracy of geological hazard ment of the aquifers and aquicludes have been classified to depiction is limited by the scale of the map (1:100 000). the five categories of pollution sensitivity (Tab. 1). All available information about the selected hazards, Between 1992 and 1994 this principle of rock body either in the form of various maps at different scales (rank- evaluation was used for the preparation of the Map of the ing from 1:25 000 to 1:200 000) and databases, or aerial and suitability for waste disposal at a scale of 50 000 concern- satellite images, have been used as a background. The fol- ing nearly the entire territory of Slovakia (36 former dis- lowing maps, prepared in the framework of the DANREG tricts except for the cities of Bratislava and Koice) programme, have also been used for the construction of the (KOVÁÈIKOVÁ &SEGÍÒ 1995). The suitability map for MEG: Surface Geological Map scale 1:100 000, Lithogen- each district consists of the land valorisation map, 2 docu- etic and thickness Map of the Quaternary scale 1:200 000, mentation maps, waste disposal sites inventory at a scale Neotectonic Map scale 1:200 000 and Engineering of 1:10 000, legend and a brief commentary. The method- Geological Maps scale 1:200 000. The results of field map- ology for their preparation was regulated by a Guidebook ping, particularly of slope deformations and erosional fea- of the Ministry of the Environment of the Slovak Republic tures, were an important source of information, too. (M≥P SR 1993). These maps, financed from the State The editors deeply regret that because of a long and seri- budget, were digitised and printed. ous illness GERHARD SCHÄFFER was not able to correct the For the MEG purposes the corresponding Suitability final version of the Map of Environmental Geohazards and maps for waste disposal (scale 1:50 000) were used in sim- 583 ©Geol. Bundesanstalt, Wien; download unter www.geologie.ac.at Table 1 Assessment of pollution sensitivity in the Slovak part of the Danube region Transmissivity of the aquifer Thickness (depth to the surface) of aquiclude Structural arrangement ∅ –3 2 –1 A 10 m s 1 = 0 – 2 m thickness of the aquiclude B = 10–4 m2s–1 2 = 2 – 5 m –5 2 –1 C = 10 m s 3 = 5 – 10 m 2A3 aquifer expressed by transmissivity D = 10–6 m2s–1 4 > 10 m E < 10–6 m2s–1 depth to the underlying aquiclude surface Pollution sensitivity category Structural arrangement of aquicludes and aquifers 1 — very high 1A4 2 — high 1A3, 2A3, 2A4, 1B3, 1B4 3 — moderate 1A2, 2A2, 3A3, 3A4, 1B2, 2B2, 2B3, 2B4, 1C3, 1C4, 2C3, 2C4 4 — low 1A1, 4A4, 1B1, 3B3, 3B4, 1C2, 2C2, 3C3, 3C4, 1D3, 1D4, 2D3, 2D4 5 — very low 4B4, 1C1, 4C4, 1D1, 1D2, 2D2, 3D3, 3D4, 4D4, E plified form. The hydraulic parameters of rocks in the impermeable cover, if there is any (considering the upper- Bratislava district have been taken from the special (scale most sedimentary series with a coefficient of permeability 1:25 000) suitability map for waste disposal of the area at a k < 10–3 cms–1), using the following scheme (Tab. 2): (VOJTAKO et al. 1991) and also from the existing boreholes Because of the vertical and/or horizontal variability of or determined by the qualified assessment. Information the parameters considered, both methods (Tab. 1 and 2) about the Quaternary rock thickness are extracted from the have to be regarded as fundamental guidelines for the Lithogenetic and thickness Map of the Quaternary (PRISTA preparation of MEG. et al. 1996a, b) and/or Engineering Geological Map Due to the lack of basic data from boreholes and labora- (KOVÁÈIK et al. 1996) prepared for the Slovak part of the tory tests in the eastern part of the territory (east of Bábolna DANREG programme. village) the assessment of the surface pollution sensitivity is In Hungarian territory the pollution sensitivity reflects based on a less strict scheme though based essentially on the degree of uppermost aquifer protection against the similar principles taking into consideration the surface geol- impact of all surface anthropogenic sources of pollution. In ogy and the depth of groundwater level. In case of the pres- the western part of the Hungarian territory (from the ence of several different layers above the groundwater table Austrian border approximately to the surroundings of their estimated, weighted average transmissivity was calcu- Bábolna village) the assessment of pollution sensitivity is lated for the purpose of the MEG. That is the reason why a based on the modified classification scheme applied in the specific sediment (e.g. loess) can be assigned to different (scale 1:100 000) map sheets of the Little Hungarian Plain sensitivity categories in different areas. For the compilation (Kisalföld) by BOLDIZSÁR [in SCHAREK (ed.) 1990, 1991a, of the MEG the materials of the relevant land management 1991b, 1993 and 1995]. projects (e.g. BOLDIZSÁR & POZSGAI 1982; KÉRI 1982; Pollution sensitivity of the superficial formations was PRAKFALVI et al. 1983, OROSZNÉ et al. 1982, Faculty... 1985) evaluated by using the combination of parameters like per- and engineering geological studies (RAINCSÁK-KOSÁRI meability, highest groundwater level and thickness of the 1993) were also used as background materials. Table 2 Assessment of pollution sensitivity in the Hungarian part of the Danube region k — coefficient of permeability t — highest groundwater level below the surface f — cover thickness –4 –1 k0 > 10 cms t0 < 1 m f0 < 1 m –4 –5 –1 k1 = 10 – 10 cms t1 = 1 – 2 m f1 = 1 – 2 m –5 –6 –1 k2 = 10 – 10 cms t2 = 2 – 5 m f2 = 2 – 5 m –6 –1 k3 < 10 cms t3 > 5 m f3 > 5 m Pollution sensitivity category Parameter combinations 1 — very high k0t0f0 2 — high k1t1f1 3 — moderate k1t2-3f2, k2-3t2f1 4 — low k1t2-3f2-3, k2-3t2f2, k2-3t3f1 5 — very low k2-3t3f2-3 584 ©Geol. Bundesanstalt, Wien; download unter www.geologie.ac.at The Austrian approach to the assessment of pollution with debris of volcanic rocks make up the slopes along the sensitivity is mainly based on the qualified assessment of bottom parts of the Krupinská planina and Burda Mts.