2.7. WATER QUALITY 2.7.1. Long-term Quality Monitoring (m. zupan) 2.7.1.1. Introduction Long-term water quality monitoring of the springs in Slovenia has been run since 1990. Already the first results of some main springs at the foot of the Trnovo plateau reminded that some pollution sources in the catchment area exist. In the frame of the present project the monitoring program in the springs was more extensive in years 1993-96. 2.7.1.2. Sampling And Chemical Analyses Program The samples for the water quality observations in the following sampling points were taken in 1993-1996: The Vipava spring 15 times for basic physical, chemical and bacteriological analysis and 6 times for the analysis of heavy metals and organic micropollutants in water and sediments and saprobiological analysis The Hubelj spring 15 times for basic physical, chemical and bacteriological analysis and 6 times for the analysis of heavy metals and organic micropollutants water and sediments and saprobiological analysis The Lijak spring 1 time for basic physical, chemical (including heavy metals and organic micropollutants in water) and bacteriological analysis in 1993; later the sampling was impossible because the borehole was stopped The Mrzlek spring 3 times for basic physical, chemical (including heavy metals and organic micropollutants in water) and bacteriological analysis The Podroteja spring 14 times for basic physical, chemical and bacteriological analysis and 6 times for the analysis of heavy metals and organic micropollutants in water and sediment and saprobiological analysis. In the catchment area two water supply captures in Čepovan (Čepovan and Čepovan Puštale) were sampled and analysed once in 1993; physical, chemical (including heavy metals and organic micropollutants in water and sediment) and bacteriological analysis The investigation program was run conforming to the methodology recommended by international organisations. 2.7.1.3. Analytical Methods And Water Quality Standards Sampling was done in various seasons of the year, preferably at low to mean low discharges. Samples for all types of analyses at one location were taken simultaneously. Samples were taken at a depth of 0.5 m and as close to the spring outlet as possible. In waters less than 1 m deep, samples were taken at mid depth. When sampling, air and water temperature, as well pH value, conductivity, free carbon dioxide and dissolved oxygen were measured. Samples for determining nitrite, chemical oxygen demand (COD), colour, and phosphates were conserved, samples for determining detergents, phenols, mineral oils, and formaldehyde were cooled. Basic physical and chemical analyses: In unfiltered, mixed samples, suspended solids, chemical oxygen demand (COD), biochemical oxygen demand (BOD), phenols, and detergents were determined. The unfiltered, sedimented sample was used to determine ammonium and nitrite ion, real colour, mineral oils, formaldehyde and ligninsulpho-nates. Other analyses were performed on samples filtered in Filtrak 388. Samples are analysed in the shortest possible time according to the following standard analysing methods for determining the basic water-pollution parameters (3, 4, 5): determination of free carbonic acid: titration with NaOH determination of dissolved oxygen: titration acc. to Winkler and measuring by an WTW probe determination of COD: K^Crp^ and KMnO^ determination of Ca and Mg ions: titration with NaEDTA nitrate ions: Na - salicylate procedure nitrite ions: procedure with sulfanilic acid solution iron ions: procedure with 1,10 - phenanthroline SiO^: procedure with ammonium molybdate solution aluminium: procedure with alizarin actual colour: comparison with K^PtCl^ standards anionic surfactants in detergents: methylene-blue method phenols: procedure with 4-aminoantipyrine ammonium ions: procedure with Nessler reagent phosphate ions: procedure with ammonium molybdate solution sodium and potassium: sulphate ions: formaldehyde: mineral oils: ligninsulphonates: flame AAS titration by thorin (6) procedure with phenilhydrazine hydrochloride (7) fluorescence measurement in hexan-extract (8) fluorescence method (9) Analyses of heavy metals and organic compounds Samphng of water, suspended solids, and sediments for analyses of metals and organic compounds (organic micropollutants) was performed according to the sampling methods as stated by DIN 38402-T15 and ISO 5667-T6. Concentrations of individual elements were measured by analytical procedures according to the standards stated in Tabic 2.10. The following organic compounds were analysed in unfiltered water by the method of gas chromatography: phenols, pesticides, polycychc aromatic hydro- lab. 2.10: Analytical methods to determine the content of metals in water, suspended solids, and river sediment. METAL WATER SEDIMENTS AND SUSPENDED SOLIDS Regulation Method Regulation Method Copper DIN38406-T7 F AAS DIN 38406-T7 F AAS Chromium DIN38406-T10 ET AAS DIN38406-T10 F AAS Nickel DIN38406-T21 F AAS DIN 38406-T21 F AAS Zinc DIN38406-T21 F AAS DIN 38406-T21 F AAS Lead DIN38406-T21 ET AAS DIN 38406X21 F AAS Cadmium DIN 38406-T19 ET AAS DIN 38406 T19 F AAS Mercury DIN 38406-T12 CVAAS DIN 38406 T12 CVAAS Notes: F AAS Atomic absoiption spectrophotometric analysis, flame AAS, instrument PE 1 lOOB ET AAS Atomic absorption spectrophotometric analysis, electrothermical AAS, instrument Zeeman 3030 CV AAS Atomic absoiptional spectrophotonietrical analysis, cold vapour AAS, instrument PE 2380 MHS 20 Tab. 2.11: Analytical methods to determine the content of organic compounds in water. Regulation Method Pesticides EPA 60S, 1982 and DIN 38407-T6 and T14 GC/MS/SIM Phenols EPA 604 and ref. 21 GC/MS/SIM PAG EPA 610 GC/MS/SIM PCB EPA 608, modified GC/ECD AOX DIN 38409-Tl 4 Stroehlein Coulomet 702 GL EOX DIN 38414-T17 Stroehlein Coulomet 702 GL carbons, (PAH) and polychlorinated biphenyles (PCB). Also the adsorbed organohalogen compounds (AOX) were analysed and GC/MS screening was performed (identification of untargeted organic compounds). Analytical methods for determining concentrations of organic compounds in water are given in Table 2.11. PCB was determined in the untreated sample of the sediment too. A GC/ MS screening was made from the extract of the sediment to identify untargeted organic compounds. As well halogenated extracted organic compounds (EOX) were analysed. Saprobiological and bacteriological analyses For the evaluation of the quality of surface waters from the biological point of view we used the saprobic system (10 - 15) and the calculation of the value of the saprobic index of a biocoenosis (16, 17). The value of the saprobic index (SI) increases with the deterioration of the living conditions from 1 to 4. Samples were taken biannually, in the cold and in the warm season of the year at lower discharges. The biological material was sampled in the littoral of the effluent down to a depth of ca. 0.5 m, where the sampling was not hampered by either water depth or speed. Semiquantitative and qualitative samples of periphyton and macrozoobenthos were taken. Macrozoobenthos was collected in the gravel to a depth of down to 15 cm in the ground semiquantitatively by means of a standard manual net (ISO 7828(E), 1985) with 0.5 x 0.5 mm mesh. With regard to the value of the saprobic index, the river is at a particular sampling point ranged into the corresponding quality class according to the values stated in Table 2.12. The bacteriological conditions of surface waters are subject to change due to the nature of the rivers, therefore the results of bacteriological analyses reflect the current state, i.e. pollution. Samples for bacteriological analyses were taken simultaneously with the samples for physicochemical analyses to be analysed according to the standard methods (4). The most probable number of Tab. 2.12: Quality classes according to the value of saprobic index. Trophic degree SI value Quality class Description of the quality of the water body oligosaprobic 1.0-1.5 1 uncharged to very little charged oligo to beta 1.51-1.8 1-2 little charged betamezosaprobic 1.81-2.3 2 moderately charged beta to aifa 2.31-2.7 2-3 critically charged alfemezosaprobic 2.71-3.2 3 heavily polluted alfa to poly 3.21-3.5 3-4 very heavily polluted polysaprobic 3.51-4.0 4 excessively polluted bacteria (MPN/1) was determined and the following more important groups of bacteria were qualitatively determined as well: faecal coliforms, faecal streptococci, Proteus sp., Pseudomonas aeruginosa, sulphite-reducing Clostridia and total number of aerobic mesophilic bacteria. Standards and guidelines for water quality assessment In general the Slovenian regulation classifies running waters with regard to their potential utilisation into four quality classes: • 1®' class: waters which in their natural state or following disinfection may be used as drinking-water, in food-processing industry, as well as in breeding high-class fish species (Salmonidae); • 2"'' class: waters which in their natural state may be used for bathing, water sports, breeding other species of fish (Ciprinidae), or following normal treatment (coagulation, filtration and disinfection), may be used as drinking-water or in food-processing industry; • class: waters which may be used in irrigation, or, following normal treatment, in industry, except in food-processing industry; • class: waters which may be used for any purpose only following an adequate treatment. The criteria used in ranging spring water courses into quality classes according to the contents of metals in water and suspended solids are shown in Table 2.13. Concentrations in bold type in the table make up the division between and quality class. Table 2.13. lists criteria for categorising watercourses into quality classes according to the content of metals in sediments. The criteria are based on natural contents of metals in carbonate sediment rocks (18, 19), amended with the results of investigation of certain surface waters in Slovenia at their springs or in polluted sections. Values in bold indicate the division between natural Tab. 2.13: Standards and guide-lines for classification of watercourses into quality classes according to the contents of metals in water and suspended solids. Meta! Hg/l Classification into quality classes 1. 2. 3. 4. Cooper <30 100 140 >140 Chromium <45 150 800 >800 Nickel <15 50 140 >140 Zinc <50 200 1400 >1400 Lead <15 50 140 >140 Cadmium <1.5 5 15 >15 Mercury <0.5 1 1.4 >1.4 Tab. 2.14: Standards and guide-lines for classification of watercourses into quality classes according to the contents of metals in river sediment Metal Hg/1 Classilicatiou into quality classes 1. 2. 3. 4. Copper <50 50-100 100-340 >340 Chromium <75 75 -150 150-540 >540 Nickel <50 50 - 100 100 - 360 >360 Zinc <650 650 -1300 1300-4600 >4600 Lead <80 80 - 120 120- 1000 > 1000 Cadmium <6 6-12 12-40 >40 Mercury <0.1 0.1 - 0.2 0.2-1 > 1 values and pollution. Table 2.14 lists criteria for categorising into 1.-2. quality class according to the content of organic micropollutants considering EC (20,21) and WHO (22) recommendations. The AOX and EOX are used as group criteria for monitoring the pollution with chlorinated organic compounds. The value of 0.5 - 2.5 jxg EOX/kg air dried sample represents the natural background, a concentration from 30 - 700 /j.g EOX/kg might cause the extermination of some benthos organisms (23). The identification of organic compounds in the GC/MS screening of samples of waters and sediments shows which organic compounds are present in watercourses and makes it possible to determine the pollution caused by man. In performing and evaluating the analyses less stress is lain on the quantity. Based on GC/MS screening, watercourses were evaluated according to the following criteria (Tab. 2.15): Tab. 2.15: Considered standards for classification of watercourses into the first(l.) and the second (2.) quality class according to the contents of organic micropollutants. ORGANIC COMPOUND 1.-2. QUALITY CLASS AOX - ng Cl/1 <5 Mineral oils - mg/1 0.01 Polychlorinated biphenyles - ng/I 0.1 Phenols - ng/1 0.001 Polycyclic aromatic hydrocarbons - ng/1 0.2 Pesticides - individual - ng/1. <0.1 Pesticides - total - ng/1 <0.5 quality class: the water shows presence of compounds of natural origin only 2"'' quality class: the water shows presence of compounds which are biodegradable and may be removed from the water with simple methods used in preparation of drinking water 3"' quality class: the water shows presence of not easily destructible com-povinds, which when infiltrating into the groundwater remain almost unchanged or are transformed into stable metabolites 4"' quality class: the water shows presence of chlorinated compounds which are typical man-caused pollutants, compounds which tend to accumulate in living beings and compounds with carcinogenic and/or mutagenic potential. 2.7.1.4. Results and water quality assessment The pollution of the water springs, in particular of the water, was relatively slight. The chemical parameters in most water samples did not exceed the normative for drinking water. On the other hand relatively high concentrations of mercury, cadmium, lead and copper in sediment samples were measured, which means that the pollution was nevertheless present in the investigated springs (Fig. 2.27.). The phenolic compounds and polycyclic aromatic hydrocarbons (PAH) were very often present in water samples of the Vipava, Hubelj and Podroteja springs (Fig. 2.28). The number of present PAHs determined in GC/MS screening was very high in water and sediments extracts. In the all investigated springs numerous compounds which originate from different human activities, were determined in GC/MS screening of water and sediment as well. 0,012- 0,01^ / , 0,008- 1 0,006- 0,004- rM 0,002- 0 mz 1993 1994 1994 1995 1995 Fig. 2.28: Polycyclic aromatic hydrocarbons and phenolic compounds in the water samples of the investigated springs (maximal values). 1993 1994 1993 »96 1933 1994 1996 1993 1994 199S Podrotoja 1993 ISM 1993 «9« tsss Fig. 2.27: Heavy metal levels (maximal values) in the sediment samples of the investigated springs. Tab. 2.16: Content of heavy metals in the sediments of the two water springs in Cepovan. Water spring Copper Zinc Cadmium Chromium Nickel Lead Mercury mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg Čepovan 58 583 4.4 81 61 <10 <0.05 Čepovan — Pultale 56 1600 6.5 37 43 228 <0.05 Tab. 2.17: Content of phtalic acid esters (sum) in the investigated springs. S« 1993 im of phtalic acid esters - 1994 g/1 1995 Čepovan 0.065 - - Vipava 0.120 0.115 0.520 Hubelj 0.126 0.200 0.360 Mrzlek 0.175 0.234 0.420 Lijak 0.145 - - Podroteja 0.260 0.615 1.110 In the catchment area we analysed two springs in Čepovan, which were polluted by polycyclic aromatic hydrocarbons in water (0.009 pig/l) and sediment. The concentrations of single PAH-s were not high but they were present in great number, thirteen in each Cepovan spring. We determined high contents of heavy metals in the sediment as well (Tab. 2.16). Phtalic acid esters were determined once a year and were found in all analysed water samples. Besides we estabhsh a trend of increasing concentration (Table 2.17). The presence of heavy metals and many different organic compounds in water and sediment samples is pointing to a constant pollution from the hinterlands. For the estimation of the water quality in the investigated springs all in the chapter 2.7.1.2 mentioned criteria have been taken into account and the results are shown in the Table 2.18. ■c »i Uk S'sf ž B. s a O p ? o 18 ^ ooooo+oooo § ^-isssgssss ^ a; Tab. 2.18: Evaluation of the quality of the investigated karstic springs in 1993-1995. 2.7.1.5. Contour diagrams of fluorescence intensity We used the excitation-emission matrix (EEM) method as pattern recognition technique and as semi-quantitative technique to follow the transport of natural and anthropogenic pollution in hydrologic system (WOLFBEISS 1993). We scanned the 3D spectra in all background samples. Emission spectra (300 nm to 550 nm, 5 nm intervals) were scanned over the range of excitation wavelengths (300 nm to 500 nm, 5 nm intervals) on the Hitachi-4500 fluorescence spectrophotometer. Slit widths for both excitation and emission mono-chromators were set at 10 nm. The comparison with the unchlorinated tap water shows that in all measured samples different organic compounds of unknown origin are present. Namely, we did not have the standards for this compounds and the determination of present compounds will be task for some investigation in the future. 2.7.1.6. Conclusions The chemical analyses of sediment in the Hubelj, Vipava and Podroteja springs have shown that pollution from the hinterlands is present and that water quality may suffer an abrupt deterioration. The results of microbiological analyses have been shown periodical pollution in the Podroteja, Hubelj and Vipava springs as well. Investigations of water quality should be followed by appropriate actions. Actions to protect water quality wherever it is still satisfactory and rehabilitation actions where appropriate. 2.7.2. Agricultural threats to pollution of water of TYnovsko-Banjska Planota (B. MATIČIČ) 2.7.2.1. Introduction The objective has been to determine the relationship between the soil water balance and mineral balance in the Karst region of Trnovsko-Banjška Planota in western part of Slovenia above Vipava valley and to find out if the possible excessive use of fertiliser and/or high intensity of animal husbandry in upland catchment area on Trnovsko-Banjška Planota could affect the quality of drinking water down in Vipava valley. The altitude of Trnovsko-Banjška Planota is about 800 m. In this region mainly shallow soil types (with depth of 10-50 cm) on limestone are found with low water holding capacity (22-142 mm) and high rate of infiltration. The amount of precipitation in Trnovsko-Banjška Planota is very high. The average annual value (1951-1980) in meteorological station Othca was 2457