International Symposium on Geography Environment and Culture in the Mediterranean Region

GROUNDWATER QUALITY AS A SECURITY CONCERN: CASE STUDY IN

Daniela ZLATUNOVA 1

Abstract The main goal is to identify the Groundwater Quality and the water security problems concerning with it in Bulgaria.The object of investigation is fresh Groundwater in Bulgaria from the zone of active water exchange. They are differentiated in separate water bodies included in different aquifers based on the age of aquifers. Generally eight layers are differentiated. The state of water bodies in the first aquifer /L1/ -Quaternary / Q or Q-N/ is considered in the article. Two groups of criteria are used to identify water security problems: The first group includes criteria of water supply quantity – part of fresh ground total abstraction from public water supply by regions for water management. Criteria for assessment of the state of the water bodies are included into the second group. Two groups of indicators are used according to Regulation №1 /SP, n. 57 from 14.07.2000/: metals and metalloids/ Iron, generally and Manganese/ and other non-organic matter / ammonium, nitrates, nitrites and phosphates. Key words: Groundwater, Security, Groundwater Quality

1. Objective, data and methods The object of investigation is fresh Groundwater in Bulgaria from the zone of active water exchange. They are differentiated in separate water bodies included in different aquifers based on the age of aquifers. Generally eight layers are differentiated. The state of water bodies in the first water layer /L1/ - Quaternary / Q or Q-N/ is considered in the article. The bodies bind to the Quaternary alluvial, pluvial and eluvia sediments, as well as sections where Quaternary sediments make common water horizon with Pliocene sediments predominantly in graben depressions in the Sought Bulgaria are related to this layer. The main goal is to identify the Groundwater Quality and the water security problems concerning with it in Bulgaria. Two groups of criteria are used to identify water security problems: The first group includes criteria of water supply quantity – part of fresh ground total abstraction from public water supply by regions for water management. Criteria for assessment of the state of the water bodies are included into the second group. Two groups of indicators are used according to Regulation №1 /SP, n. 57 from 14.07.2000/: metals and metalloids/ Iron, generally and Manganese/ and other non-organic matter / ammonium, nitrates, nitrites and phosphates /. The ecological threshold for the preservation of groundwater from pollution and damage is determined and the threshold for pollution of the groundwater according to the appendix № 3./Regulation 1/. According to Art.86.(1) the condition of the groundwater is defined as follows: • Groundwater in an excellent condition are groundwater in which the values of the indicators due to Appendix № 3 are below the ecological threshold; • Groundwater in a very good condition are groundwater in which the values of the indicators due to Appendix № 3 are between the ecological threshold and the threshold of pollution;

1 University, Bulgaria International Symposium on Geography Environment and Culture in the Mediterranean Region

• Groundwater in a bad condition are groundwater in which the values of the indicators due to Appendix № 3 are above the threshold of pollution; • Groundwaters in a very bad condition are those at which damage is occurred.

2. Results and Discussion Availability of Groundwater recourses. The territory of the country is divided into three regions – Lower Danube Artesian Region, Medial Region and Rila- Rodopi Region according to the Programme for Monitoring of the Groundwater, the MEW. A varied geological situation in the country predetermines formation of all basic types groundwater –leak, karst (karst- leak) and pore. /Table 1/.

Water Exploitation Exploitation Types m3/s Management Resources Resources Regions m3/s m3

Danube 25 – formed on 800.10 6 Pore * territory Karst * 9 65 –attracted by 2.10 Karst – leak * the River Danube Black Sea 21 -22 6.6.10 6 – Pore 1. 8-1 .9 6.9.10 6 Karst and Karst – 20 leak East White Sea 37 11.6.10 6 Leak 2.81 Karst 5.85 Pore 28.5 West White Sea 9.3 – 9.5 2.9.10 6-3.0.10 6 Pore 3.7

Karst 2.9

Leak 2.9

Table 1. Groundwater recourses

The Danube region of the basin water management covers bigger part of the North Bulgarian Artesian Region, which includes the paramount geo-structural units like the North Bulgarian vaulted raising, Lom depression, entire Fore-Balkan and the northern slopes of the West Balkan tectonic zone. Only the Eastern part - Varna Artesian Basin is referred to the Black Sea region for basin management. The potential exploitation resources of the groundwater in the Danube region of basin management amount to 90 m3/s, 25 m3/s or 800. 10 6 m3/a of which is formed on the territory of the region and 65 m3/s or 2.0.10 9 m3/a are likely attracted waters by the River Danube. The wide karst-leak water horizons in thick up to several hundred meters Malm - Valanginian and Barremian -Aptian limestone sediments are formed in the North East Bulgaria. They formed two floor disposed water horizons divided by the thick layered Hautervian marls in the South and Central parts of the North Bulgarian vaulted rising and they formed because of the facial changes a common karst-leak water horizon to the north. The wide Lom Artesian Basin exists in the North-West Bulgaria. Parts of the middle and lower courses of the rivers Archar, Lom, Tsibritsa, Ogosta, Skat fall into its range. Two considerable water bear horizons – Pontian and Sarmatian and one weaker aquifer horizon – Dakroman are formed into this basin. International Symposium on Geography Environment and Culture in the Mediterranean Region

Mountain karst is developed predominantly in the region of the Fore-Balkan. Water- abundant karst basins are formed into limestone and dolomites of the Middle Triassic and into carbonate facies of the Upper Jurassic – Lower Cretaceous . Such karst basins are these in the region of Montana (the course of the river Ogosta), into Vrasta Balkan (the courses of the rivers Ogosta and ), into anticlinoria (the course of the river Vit ). Discharge of the basins is made through big karst springs but the water masses are quite unevenly distributed during the year – high debits during the winter-spring period and more lower during the summer-autumn period. The exploitation groundwater resources of the Black Sea region for water management are estimated at about 21 000-22 000 dm 3/s. 1 800-1 900 dm 3/s of them are pore and about 20 000 dm 3/s are karst and leak-karst groundwater. The pore groundwater are formed into aquifer horizons in alluvial and pluvial depositions as well as into the loess complex . The horizons in relation to the degree of the water- abundance mostly are referred to the moderate water-saturated and in some sections to the high water-saturated. The aquifer horizons in the terraces of the rivers Golyama Kamchia, Provadiiska, Aitoska, Sredetska, Fakiiska, Veleka and other are with the biggest natural and exploitation resources. These waters formed into the aquifer horizons of the Paleogene in the depression, in the Oder retinue of the Sarmatian near , Nessebar and in the course of the river Provadiiska are referred to the same type groundwater. Waters are predominantly artesian. The karst water horizons of the Lower Cretaceous/Barremian -Aptian and Malm - Valanginian /and Miocene/ the Oder and Karvune retinues are in the structure of the Varna Artesian Basin Huge resources of groundwater are included into three horizons. Their feed is from the atmospheric and fluvial water. The huge karst springs at Devnia and Zlatina village /3800 dm 3/s / are drained by the river system and by the sea. Artesian waters are in the bigger part of distribution of the Malm- Valanginian horizon but in dipper east parts of the basin and also with increased temperature. Several karst basins / , Madara, Kotel and other/ with considerable natural and exploitation resources are formed in the karst-limestones from the Upper Cretaceous in the Fore-Balkan and the Stara Planina part of the region. Furthermore sought of the valley of the river Golyama Kamchia the Upper Cretaceous aquifer horizon is revealed as a long fragmental strip by which considerable water quantities are drained most of them caught for public water supply. The feed of the horizon is by the atmospheric and fluvial waters. It is drained by several springs with huge debit /at the villages Troista, Divdiadovo, Madara, Kotel, Kupilovo and other/. Three karst basins with considerable natural and exploitation resources are formed into the Triassic limestones in the region of Strandga. These are Malko Turnovo, Bashdermen and Varovnik basins. The draining of the karst waters realizes by several springs with debits over 50-100 dm 3/s. / Dokuzak, Katun, Bashdermentski kainatsi, Golemia vzriv, Ezeroto, Varovnik and other/. Leak-karst waters are formed over huge areas out of these basins in less karst and cracked limestones and dolomites. The leak waters have the biggest territorial distribution in the whole Black Sea region for water management. They are formed in creaked environment created in all rock complexes. Although related with weak water formations they are of great interest for water supply of small settlements and economic projects. The significance of the Upper Cretaceous, volcanic and volcano-sedimentary retinue in the central parts of the Burgas synclines, where several thermo-mineral sources /Burgas ki bani, Aitos, Polyanovo, Medevo and other/ as well as sources of fresh waters are bounded to the faulting zones. Practically waterless complexes are wide spread in the Black Sea region except weak water formation. They take about 63% of its area in the course of the river Golyama Kamchia and in the course of Burgas Rivers – 48%. The Lower Cretaceous retinues – Kamchia and International Symposium on Geography Environment and Culture in the Mediterranean Region

Gorna Oryahovitsa as well as Flishki complexes of the Paleogene in the East Stara Planina can be pointed as the most waterless. Over 86 % of the exploitation resources are concentrated in the Northern parts of the region, and in the Southern 13-14 %. This is due to the huge resources of the karst water horizons of the Varna Artesian Basin. Total water resources of the groundwater in the East White Sea basin for water management amount to about 37 m 3/s, which represents a total module of the exploitation resource of 1.09 l/s.km 2 for the entire catchment area of 34169 km 2. The total exploitation module of the groundwater for the different river courses is 1.44, 0.63 and it is 0.38 l/s km 2 respectively for Maritsa, Toundzha and Arda. The main accumulators of the leak waters are cracked rock formations in the mountain sections – in the Stara Planina, Sredna Gora , Sakar, Strandzha, Rodopi Mauntains and Rila as well as in the less risen parts (Sveti Iliiski uplands, Manastirski uplands and other). Bearers of the leak waters as a whole are with low water quantity . The module of the groundwater runoff in most of the cases is under 0.1 l/s.km 2 and then the rocks are considered as un-watered. Karst groundwater are accumulated in the karst formations with different age major between them are marbles of the Precambrian Dobrostan retinue, developed into Rodopi area (with the same age are also others, have already silicate- carbonate retinues – Belashtenska, Lukovishka, Bachkovska comprised karst marble seam or more significant marble litho- bodies. The most significant karst basins here are: Nastan-Trigradski(springs near Nastan, spring “Vrisa” and other); Velingradski (spring “Kleptuza” and other) - Ognyanovski( spring Three voditsi” and other); (spring Hubcha and other) The debit of every of these springs reach hundred liters per second. The pore materials and mainly the alluvial Cretaceous sediments between them are the most significant accumulator of the ground waters in the region. The Gornotrakiiskatta depression spread all over the flat part of the territory between towns Belovo and along the river Maritsa is the biggest structure in the region and in the country bearer of the pore waters. Here the exploitation resources are estimated at 21010 l/s (intermediate module of the exploitation resource – about 5.8 l/s.km 2). The next general structure according to the quantity of the pore resources are Balkan graben depressions – Pirdopski and Karlovski Grabens , Kazanluk-Sheinovski, Vetrenski, Tvardishki and Slivenski sections of the respective grabens as well as along the river Mochuritsa in the Stralga – Karnobatski graben. The total exploitation resources of the pore waters here amount to 4745 l/s at average module of the exploitation resource 3,4 l/s.km 2 . The graben – with 1350 l/s at module about 5,2 l/s.km 2,Vetren section - 1120 l/s and 3.8 l/s.km 2 and section 915 l/s and exploitation module of 4,1 l/s.km 2 are with the highest exploitation resources among the Balkan grabens . Among the rest structures with the pore waters more abundant are depression with the exploitation resource of 600 l/s ( М ≈ 3.5 l/s.km 2, calculated due to the total area of development of the Neogene’s paleo-bed and at the Quaternary terrace of the river Harmanliiska), – depression – with 1030 l/s at М ≈ 2.4 l/s.km 2 and basin with the exploitation resource of 620 l/s. The exploitation quantities in the Haskovo depression amount at about 400 l/s (67% from the exploitation resource) whereas for the others two structures the total resource is acquired by the exploitation. The pore waters represent about 78 % from the total exploitation resource. The second of significance for the region are resources of the karst waters represented about 16% from the total exploitation resource. The exploitation resources, included attracted and thermo- mineral resources of the groundwater within the range of the West White Sea region for water management are estimated approximately at about 9,3 – 9,5 m3/s. Aquifer formations are: Hydro-Geological Systems HGS (massives) with leak waters in the Preneogene rock formations; Karst systems in the Mesozoic carbonate rocks and Precambrian marbles;

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Regions for water Regions % of the taken management away groundwater

Danube 2,05 Montana 8,26 0,31 10,54 67,69 7,93 Veliko Turnovo 2,05

Ruse 18,18

Silistra 37,53 88,14 average 24,27 Black Sea Shumen 7,37 52,81 Turgovishte 9,7 Varna 42,98 Burgas 3,47

average 23,27

East White Sea 5,74 Yambol 61,84 Haskovo 28,4 Sliven 3 28,01 9,82

Smolyan 1,75 Kurdzhali 3,48

average 17,76

West White Sea Sofia city 4,58 sofia 17,88 8,36 17,43 6,73 average 10,99

Table 2. The percentage of the taken away groundwater from the totally taken away fresh waters by areas and regions for water management in 2003

Sedimentation’s layered basins with pore waters in the Quaternary river’s sedimentation s and sporadically in the Neogene’s depositions of hollow’s basins between mountains. It gets clear as a result of the analysis that prevailing for the territory of the country are the pore groundwater which are accumulated in the river’s terraces and in which the aquifers are with very good filtration features. On one hand conditions for pollution of shallow groundwater are created, on the other hand attracting river’s waters to the water pumping equipment exist there, Extent of dependence of the social-economic activity from the groundwater International Symposium on Geography Environment and Culture in the Mediterranean Region

Taken away groundwater as a whole for Bulgaria are 6.7 % by the totally taken away fresh waters. Considerable differences in territorial distribution of the exploitation groundwater resources define also considerable differences in taken away groundwater in different areas for management and regions. i.e. taken away groundwater in 50% of the regions are over 10% from the totally taken away fresh waters. At the same time taken away groundwaters in 21 % of the regions are between 10% and 20% from the totally taken away fresh waters and in 4 regions they are over 50% from the totally taken away fresh waters./ Table 2.and Figure 1/. The Danube region for management is relatively the richest of the groundwater between the rests of the regions for water management. This predetermines also the high percentage of taken away groundwaters - 24% from the totally taken away fresh waters. The percentage of the Black Sea region for management – 23% is almost analogical. The reason for this is that in the North-East Bulgaria / east of the catchment area of the river Rusenski Lom/ carbonate rocks which predetermine lack of the surface runoff have a wide distribution. Hence in this part of Bulgaria groundwaters are the only one source for water supply , which predetermine also high percentage of the taken away groundwater - Varna region /43%/, Dobrich – 88% and Razgrad – 53%. At the same time groundwater have predominant significance for drinking and household water supply for the settlements located along the lower course of the river Osam – municipalities , Pordim, Levski, Nikopol, and , which predetermine the high per cent of the groundwater of the Lovech region /67,7% from the taken away fresh waters/. Groundwater quality The Danube region for the water management Groundwater in most of the cases are in excellent and good ecological condition / water bodies BG_015; BG_16;BG_019/ according to Ammonium ions. Table 3, Figure2.

EWN Code Name of the max. max. Petrographic Thickne Depth to groundwater length width (in description ss of groundwat body (in km): km): the er (in m)

Min:

4 ground water body (in m) BG_GW_B Alluvial Aquifer 14 4 Classtic, Gravel, 8 6 G001 - - Sandy, Medial Novo selo Lowland BG_GW_B Alluvial Aquifer 28 8 Classtic, Gravel, 20 6 G002 - Vidin Sandy, Medial Lowland BG_GW_B Alluvial Aquifer 11 3 Classtic, Gravel, 11 6 G003 of Archar- Sandy, Medial Orsoya Lowland BG_GW_B Alluvial Aquifer 10 3 Classtic, Gravel, 8 6 G004 - Tzibritza Sandy, Medial Lowland BG_GW_B Alluvial Aquifer 11 4 Classtic, Gravel, 7 6 G006 - Ostrov Sandy, Medial Lowland International Symposium on Geography Environment and Culture in the Mediterranean Region

BG_GW_B Alluvial Aquifer 27 10 Classtic, Not 16 2 G007 - Cherno pole spec. sand, Not Lowland specified, Medial BG_GW_B Alluvial Aquifer 30 5 Classtic, Gravel, 12 8 G008 - Belene- Sandy, Medial Svishtov Lowland BG_GW_B Alluvial Aquifer 39 9 Classtic, Gravel, 15 8 G010 - Brashlyan Sandy, Medial Lowland BG_GW_B Alluvial Aquifer 15 4 Classtic, Gravel, 8 8 G012 - Aydemir Sandy, Medial Lowland BG_GW_B Alluvial Aquifer 50 3 Classtic, Gravel, 6 2 G014 of Lom river Not specified, Medial BG_GW_B Alluvial Aquifer 43 1 Classtic, Gravel, 12 2 G015 of Tzibritza Not specified, river Medial BG_GW_B Alluvial Aquifer 82 3 Classtic, Gravel, 8 2 G016 of Ogosta river Not specified, Medial BG_GW_B Alluvial Aquifer 85 4 Classtic, Gravel, 4 2 G019 of Vit river Not specified, Medial BG_GW_B Alluvial Aquifer 85 7 Classtic, Gravel, 5 1 G020 of Osam river Not specified, Medial BG_GW_B Pliopleystotze 23 6 Classtic, Gravel, 4 15 G028 ne aquifer in Clayey, Medial the west of Lom river BG_GW_B Pliopleistotzen 35 19 Classtic, Gravel, 5 10 G029 aquifer Clayey, Medial between Lom and Tzibritza river BG_GW_B Pliopleystotze 60 48 Classtic, Gravel, 5 5 G035 n aquifer Not specified, between Medial Osam and Yantra rivers BG_GW_B Alluvial Aquifer 50 5 Classtic, Not 5 3 G025 of Kamchiya spec. sand, Not river specified, Medial BG_GW_B Alluvial Aquifer 66 4 Classtic, Not 3 3 G026 of Provadiya spec. sand, Not river specified, Medial

BG_GW_B N-Q Aquifer of 71 14 Classtic, Not 15 1 G074 spec. sand, Not Kettle specified, Medial BG_GW_B Upper Trakiya 131 60 Classtic, Not 1-580 3 G100 Lowland - N-Q spec. sand, Aquifer in Sandy, Small Pazardjik - International Symposium on Geography Environment and Culture in the Mediterranean Region

Plovdiv BG_GW_B U. Trakiya 43 38 Classtic, Gravel, 25 5 G103 Lowland - Pg- Not specified, N-Q Aquifer in Medial Yambol- Elhovo Area BG_GW_B N-Q Aquifer - 32 9 Classtic, 350 3 G143 Gotze Delchev Boulders, Not specified, Medial Table 3. General Characterization of the Groundwater Body

The average concentrations of many years are in an interval 0.12 – 1.2 mg/dm 3 for the period 1995 – 2005. The groundwater / BG_001/ in the Danube river Lowland Bregovo-Novo selo as well as the groundwater in the river terrace of the river Lom/ BG_028/ and between the rivers Lom and Tsibritsa/ BG_029/ are in bad ecological condition according to this indicator / the average concentrations of many years are higher than1.2 mg/dm 3/.Table 4. Groundwaters in the Danube River Lowlands as a whole are in bad ecological condition according to the Nitrate ions . i.e. the highest are exceeds of the concentrations of these ions above the threshold of pollution /30 mg/dm 3/ in the groundwater of the Brashlyan Lowland / 3.4 times/, alluvial terrace of the river Vit /1.7 times/ and of the river Osam / 1,4 times/. At the same time the groundwater in the Chernopolskata Lowland / BG_007/ and Aidemirskata Lowland are in good ecological condition. Waters in the alluvial terraces of the river Ogosta and the Plio-pleistocene horizon located between rivers Osam and Yantra are with concentrations between the ecological threshold and the threshold of pollution. The ecological condition of the groundwater according to the indicators Nitrite ions and Phosphates ions is defined as a good. Considerably higher are only concentrations of Phosphates ions in the waters of the river Osam terrace / average concentration 25.72 mg/dm 3/. Groundwater according to indicator Iron /total/ in the Ostrovska Lowland/ BG_006/, as well as in the river terrace of the river Ogosta /BG_016/ and in the Plio-pleistocene layer located west of the river Lom /BG_028/ are in bad ecological condition. Groundwater in other Danube river Lowlands /Bregovo-Novo selo; Vidin; Archar-Orsoya; Chernopole;Belene- Svishtov; Brashlyan /are in good ecological condition. The average concentrations of Iron are in the interval0.06 – 0.14 mg/dm 3./Table 4/. EWN Code Name of the Ammoniu Nitrate Nitrite Phosp Iron Mang groundwater m ions ions hates /total? anese body ions ions BG_GW_BG001 Alluvial Aquifer min 0.00 0.28 0.02 0.00 0.40 - Bregovo-Novo max 796.0 209.5 5.93 0.27 5.08 selo Lowland avg. 21.02 37.84 0.68 0.06 1.38 BG_GW_BG002 Alluvial Aquifer min 0.56 0.00 0.00 0.24 - Vidin Lowland max 621.0 4.56 0.47 5.90 avg. 38.04 0.23 0.08 1.28 BG_GW_BG003 Alluvial Aquifer min 0.00 0.00 0.36 of Archar- max 4.86 0.21 4.15 Orsoya Lowland avg. 0.22 0.06 1.29 BG_GW_BG006 Alluvial Aquifer min 5.90 0.00 0.00 - Ostrov max 140.8 20.0 20.0 International Symposium on Geography Environment and Culture in the Mediterranean Region

Lowland avg. 32.07 1.25 1.25

BG_GW_BG007 Alluvial Aquifer min 0.41 0.00 0.38 - Cherno pole Lowland max 37.33 0.40 2.90

avg. 14.06 0.10 1.11 BG_GW_BG008 Alluvial Aquifer min 0.00 0.47 - Belene- max 0.45 3.30 Svishtov Lowland avg. 0.12 1.61 BG_GW_BG010 Alluvial Aquifer min 10.0 0.00 0.68 - Brashlyan max 143.0 0.59 1.57 Lowland avg. 102.18 0.14 0.98 BG_GW_BG012 Alluvial Aquifer min 0.01 0.00 - Aydemir max 71.76 1.50 Lowland avg. 11.54 0.39 BG_GW_BG014 Alluvial Aquifer 0.42 0.00 0.001 0.24 of Lom river min 186.6 4.90 0.12 4.03 max avg. 31.90 0.41 0.07 1.14 BG_GW_BG015 Alluvial Aquifer min 0.07 0.00 0.00 of Tzibritza river max 1.70 0.06 0.36 avg. 0.70 0.04 0.11

BG_GW_BG016 Alluvial Aquifer min 0.05 0.57 0.00 0.56 0.70 of Ogosta river max 0.50 154.5 0.09 5.40 5.80 avg. 0.28 22.03 0.03 2.54 1.66 BG_GW_BG019 Alluvial Aquifer min 0.00 0.00 0.00 0.00 0.00 0.40 of Vit river max 0.68 175.0 0.33 0.33 0.37 4.70 avg. 0.14 51.37 0.03 0.15 0.09 1.67 BG_GW_BG020 Alluvial Aquifer min 6.21 0.00 0.00 0.43 of Osam river max 67.66 433.2 0.91 8.00 avg. 41.04 25.72 0.17 1.82 BG_GW_BG028 Pliopleystotzen min 0.64 0.00 0.01 1.04 e aquifer in the max 1.80 0.07 16.60 6.00 west of Lom river avg. 1.19 0.03 5.92 4.33

BG_GW_BG029 Pliopleistotzen min 3.80 0.64 aquifer max 82.70 1.10 between Lom and Tzibritza avg. 30.23 0.87 International Symposium on Geography Environment and Culture in the Mediterranean Region

river BG_GW_BG035 Pliopleystotzen min 0.61 0.00 0.40 aquifer max 38.98 0.36 4.00 between Osam and Yantra avg. 20.71 0.06 1.49 rivers BG_GW_BG025 Alluvial Aquifer min 1.39 0.02 0.00 0.16 of Kamchiya max 135.1 0.42 1.98 2.24 river avg. 17.30 0.13 0.09 0.75 BG_GW_BG026 Alluvial Aquifer min 11.51 0.24 of Provadiya max 11.51 0.24 river avg. 11.51 0.24 BG_GW_BG074 N-Q Aquifer of min 0.00 0.00 0.24 Kazanlak Kettle max 40.80 0.48 1.90 avg. 16.99 0.23 0.87 BG_GW_BG100 Upper Trakiya min 0.00 0.00 0.00 0.00 0.00 0.00 Lowland - N-Q max 1.40 23.60 2.54 1.00 23.0 4.04 Aquifer in Pazardjik - avg. 0.42 9.33 0.11 0.24 0.92 1.36 Plovdiv

min 0.00 0.00 0.00 0.00 max 1.70 34.51 88.02 15.04 avg. 0.21 3.54 21.92 1.91 BG_GW_BG143 N-Q Aquifer - min 3.80 0.64 Gotze Delchev max 82.70 1.10 avg. 30.23 0.87 Table 4. Concentrations of the ecological indicators according to water bodies

Groundwater in all the Danube River Lowlands and in the river terraces of almost all tributaries of the river Danube are in bed ecological condition according to the Manganese Indicator. The average concentrations in the waters of the Danube River Lowlands are changed from 0.39 mg/dm 3 up to 1.69 mg/dm 3 and exceed the threshold of pollution /0.05 mg/dm 3/ respectively from 7.8 times up to 34 times. Repeatedly higher are concentrations of the Manganese in groundwater in the river Osam terrace /1.82 mg/dm 3/ and in the Plio- pleistocene horizon west of the river Lom /4.33 mg/dm 3/. Black Sea basin for water management Risen concentrations of the indicators Nitrate, Phosphates, Iron Ions and Manganese are typical. But ecological condition is estimated as good due to indicators Nitrate, Phosphates Ions and total Iron, whereas ecological condition is estimated as bad according to the Manganese content. Higher concentrations of the pointed indicators are typical for the Quaternary aquifer of the rivers Kamchia and Provadiiska / water bodies BG_025 and BG_026/. Exceeds over the threshold of pollution according to the indicator Manganese for both water bodies are respectively 15 times / BG_025 / and 4.8 times/ BG_026/. East White Sea Basin for water management International Symposium on Geography Environment and Culture in the Mediterranean Region

Groundwater of the Quaternary aquifer in the Pazardzhik – Plovdiv region / Ammonium ions, Nitrite ions and Phosphates ions/ , the Kazanluk hollow / Nitrate ions and Phosphates ions/ are in good ecological condition according to the indicator Ammonium ions, Nitrate ions, Nitrite ions and Phosphates ions. The described groundwaters are in bad ecological condition according to the indicators Iron and Manganese. West White Sea Basin for water management Groundwaters of the Quaternary horizon in the region of the town Gotse Delchev are in bad ecological condition according to the indicators Nitrate and Manganese. The exceed over the threshold of pollution according to the indicator Nitrate Ions is insignificant, whereas it is significant about the Manganese -17,4 times.

Conclusion Groundwaters take significant percentage in public water supply in different regions for water management in Bulgaria. Groundwaters of the Quaternary aquifer are shallow occurred and they are highly open to pollution in relation to this. Exceed concentrations in different water bodies are as a result of the agriculture activity, which in most of the cases does not correspond to good agriculture practices. Exceed concentrations in particular cases are also as a result of lack of the sewerage for several settlements /mainly in the villages/ and of the purification stations for the waste waters. Exceed concentrations mainly of Iron and Manganese in groundwater are poisonous for the health of people. Their purification is necessary according to this.

References Antonov, Hristo./1980/ Groundwater in Bulgaria, Sofia General scheme for utilization of water recourses in water management regions, Bulgaria, volume 1,2,3,4,5. Sofia