European Union Water Initiative Plus for the Eastern Partnership Countries (EUWI+)

Result 2

IMPROVEMENT OF THE GROUNDWATER MONITORING NETWORK IN THE - AND RIVER BASIN

Moldova

Final report; December 2020

Improvement of GW monitoring network

Beneficiaries

Agency of Geology and Mineral Resources (MD) Responsible EU member state consortium EUWI+ project leader

Mr Alexander Zinke, Umweltbundesamt GmbH (AT) EUWI+ country representative in

Mr Victor Bujac Responsible international thematic lead expert

Andreas Scheidleder, Umweltbundesamt GmbH (AT) Responsible national thematic lead expert

Boris Iurciuc, Agency of Geology and Mineral Resources (MD)

Authors

Aurelia Donos, Oleg Prodan, Maria Titovet, Tatiana Matrasilova, Nadejda Ivanova all State Enterprise Hydrogeological Expedition of Moldova (MD)

Disclaimer: The EU-funded program European Union Water Initiative Plus for Eastern Partnership Countries (EUWI+) is im- plemented by the United Nations Economic Commission for Europe (UNECE), the Organisation for Economic Co-operation and Development (OECD), both responsible for the implementation of Result 1, and an EU Mem- ber States Consortium comprising the Environment Agency Austria (UBA, Austria), the lead coordinator, and the International Office for Water (IOW, France), both responsible for the implementation of Results 2 and 3. The program is co-funded by Austria and France through the Austrian Development Agency and the French Artois-Picardie Water Agency.

This document was produced with the financial assistance of the European Union. The views expressed herein can in no way be taken to reflect the official opinion of the European Union or of the Governments of the Eastern Partnership Countries.

This document and any map included herein are without prejudice to the status of, or sovereignty over, any territory, to the delimitation of international frontiers and boundaries, and to the name of any territory, city or area.

Imprint

Owner and Editor: EU Member State Consortium Umweltbundesamt GmbH Office International de l’Eau (IOW) Spittelauer Lände 5 21/23 rue de Madrid 1090 Vienna, Austria 75008 Paris, France

Responsible IOW Communication officer: Ms Chloé Déchelette [email protected]

December 2020

2 Improvement of GW monitoring network

CONTENTS

1 Executive summary ...... 6 2 introduction ...... 7 3 Description of the Working areas ...... 8 3.1 Physical-Geographical Conditions ...... 8 3.1.1 village ...... 8 3.1.2 Balabanu village ...... 8 3.1.3 Petrunea village ...... 9 3.2 Geological Structures ...... 13 3.2.1 Congaz and Balabanu ...... 13 3.2.2 Petrunea village ...... 16 3.3 Hydrogeological Conditions ...... 18 3.3.1 Congaz and Balabanu ...... 18 3.3.2 Petrunea village ...... 21 4 Qualitative Characteristics of Groundwater ...... 23 4.1 Congaz village ...... 23 4.2 Balabanu village ...... 23 4.3 Petrunea village ...... 24 5 Sanitary Protection Zones ...... 25 6 Steps Of Water Well Drilling ...... 26 7 Geological-Technical Sections of the Projected Monitoring Wells ...... 27 8 List of References ...... 30 9 Annexes ...... 31

Improvement of GW monitoring network

Abbreviations ADA ...... Austrian Development Agency DoA ...... Description of Action DG NEAR ...... Directorate-General for Neighbourhood and Enlargement Negotiations of the European Commission EaP ...... Eastern Partnership EC ...... European Commission EECCA ...... Eastern Europe, the Caucasus and Central Asia EMBLAS ...... Environmental Monitoring in the Black Sea EPIRB ...... Environmental Protection of International River Basins ESCS ...... Ecological Status Classification Systems EU ...... European Union EU-MS ...... EU-Member States EUWI+ ...... European Union Water Initiative Plus FD ...... Floods Directive GEF ...... Global Environmental Fund ICPDR ...... International Commission for the Protection of the Danube River INBO ...... International Network of Basin Organisations IOWater/OIEau .... International Office for Water, France IWRM ...... Integrated Water Resources Management MSFD ...... Marine Strategy Framework Directive NESB ...... National Executive Steering Board NFP ...... National Focal Point NGOs ...... Non-Governmental Organisations NPD ...... National Policy Dialogue OECD ...... Organisation for Economic Cooperation and Development RBC ...... River Basin Council RBD ...... River Basin District RBMP ...... River Basin Management Plan RBO ...... River Basin Organisation ROM ...... Result Oriented Monitoring SCM ...... Steering Committee Meeting (of the EU Action EUWI+) SEIS ...... Shared environmental information system TA ...... Technical Assistance ToR ...... Terms of References UBA ...... Umweltbundesamt GmbH, Environment Agency Austria UNDP ...... United Nations Development Programme UNECE ...... United Nations Economic Commission for Europe WISE ...... Water Information System for Europe WFD ...... Water Framework Directive

4 Improvement of GW monitoring network

Country Specific Abbreviations Moldova AAM ...... Agency “Apele Moldovei” AGMR ...... Agency for Geology and Mineral Resources AMAC ...... Association of Apacanals ANRE ...... National Agency for Economic Regulation of the Energy Sector (also regulates WSS) EHGeoM ...... State Enterprise Hydrogeological Expedition of Moldova MoAgri ...... The Ministry of Agriculture (of the Republic of Moldova) MoENV ...... The Ministry of Environment (of the Republic of Moldova) Moldova ...... Republic of Moldova SHS ...... State Hydrometeorological Service

Improvement of GW monitoring network

1 EXECUTIVE SUMMARY

The “European Union Water Initiative Plus for Eastern Partnership (EaP) Countries (EUWI+)” in- volves six eastern neighbours of the EU: Armenia, Azerbaijan, Belarus, Georgia, Moldova and . The EUWI+ project addresses existing challenges in both development and implementation of efficient management of water resources and in particular the water monitoring capacities. It spe- cifically supports the EaP countries to move towards the approximation to EU acquits in the field of water management as identified by the EU Water Framework Directive Following up the gaps in the groundwater monitoring network of the Danube Prut and Black Sea Riv- er Basin in the Republic of Moldova, which were identified within a previously performed assessment, this study contributes to the improvement of the groundwater monitoring infrastructure in two groundwater bodies. This study covers the following elements:  the precise location of three new groundwater monitoring wells, which are about to complement the existing monitoring network,  the characterization of the hydrogeological conditions and technical sections of the projected wells,  the technical steps of drilling the wells including the description of the necessary equipment,  the coordination with all organizations to allow the future drilling of wells including: urban certifi- cate from the Primary, permission from the territorial ecological agency and coordination with the architect for the construction of the well, and  all necessary certificates. This study forms the basis of contracting the drilling of these three wells in a future step.

6 Improvement of GW monitoring network

2 INTRODUCTION

At present in the Republic of Moldova, groundwater is the main source of drinking water for two thirds of the population and the requirements for the supply of drinking water to the population are increasing quite rapidly. This situation and perspective requires improved, regular monitoring of groundwater quantity and quality to enable efficient groundwater management. The phreatic and the deep groundwater resources have a special importance for the Republic of Mol- dova. While the deep groundwater resources are mainly used for central drinking water supply, most of the rural population is self-supplied with drinking water from the phreatic groundwater that is cap- tured through shallow private wells or springs. In the years 2019/2020 a Technical and survey report on the proposed improvement of the groundwa- ter monitoring network in the Danube-Prut and Black Sea River Basin in Moldova was contracted by the EUWI+ project“ which identified gaps in the groundwater monitoring network and proposed the need for including existing springs and establishing new monitoring wells for complementing the exist- ing monitoring network. Together with already existing springs, which can easily be integrated into the national groundwater monitoring network, three new shallow boreholes are proposed to be established in order to improve the existing groundwater monitoring program: two wells in GWB MDDBSGWQ220 and one in GWB MDPRTGWQ510. The proposed new wells are located near studied shallow wells where the ground- water quality was analysed and the expected groundwater levels were determined. To drill these three new monitoring wells, three projects have to be carried out which comprises the concise geological-hydrogeological description of the territory, the chemical composition of the groundwater, as well as the measures regarding sanitary protection. The projects are completed with construction diagrams of the wells and the basic hydrogeological data. The three wells are proposed to be established in the village of Conga in the ATU, in the village of Balabanu in the and in the village of Petrunea in the Glodeni district. These projects are to be coordinated by the relevant authorities.

7 Improvement of GW monitoring network

3 DESCRIPTION OF THE WORKING AREAS

3.1 Physical-Geographical Conditions

The climate of the Republic of Moldova is temperate continental. The average annual air temperature is +8 to +10°C, and the temperature of the soil surface is +10 to +12°C. The compact frost-free period averages 170 days in the north and 190 in the south of the country, but in some years its duration can reach 200–230 days. Winters in the Republic of Moldova are cold, with average temperatures between -4°C and -6°C. Summer in the Republic of Moldova is warm, with average temperatures of 25–27°C in June and 29–32°C in July and August. The territory of the Republic of Moldova belongs to the area with insufficient humidity. The amount of precipitation decreases from northwest to southeast, from 620 to 400 mm during the year. Precipita- tion falls mainly in the warm period of the year in the form of rain showers and only about 10% of their annual amount is in the form of snow. The snow cover is unstable.

3.1.1 Congaz village

From the viewpoint of geomorphology, the sector envisaged for drilling a monitoring well is within the limits of the Plain of Bugeac Steppe. It has a strong fragmented relief of a system of valleys and ra- vines, the development of which is influenced by the geological structure (the presence of a relatively thick cover of loess and sandy rocks), the torrential character of precipitation and the excessive land development. In the region of the researched sector, altitudes of 40–30 m a.s.l. predominate. The altitude of the well pithead will be +35 m a.s.l.. The coordinates in the MOLDREF-99 system are: X - 214860.7; Y - 105556.5 (Figure 1). The depth of the well will be 10 m. The well is intended for monitoring the Pliocene-Pleistocene groundwater body MDDBSGWQ220. The hydrographical network is assigned to the Ialpug river basin and is represented by small streams by size, most of them run dry during the summer. The river valleys are characterised by an asymmet- ric shape. At higher altitudes they are deeper and are characterized by steep gradients and at low altitudes they are smooth and wide. In the southern part, at a distance of 720 meters from the re- searched sector there is the Cerac river, a tributary of Ialpug river. In the eastern part at a distance of about 200–250 meters from the working area of Congaz there is the river Ialpug. The Ialpug river orig- inates near the village of Tomai (), flows south in parallel to the Prut River, passes through the territory of Cimislia District, ATU Gagauzia, Taraclia District, then District of Ukraine and flows into Lake Ialpug near the city of Bolhrad.

3.1.2 Balabanu village

From the perspective of geomorphology, the sector envisaged for drilling the monitoring well is located in the area between the Hills of Tigheci and the Plain of Bugeac Steppe. The Hills of Tigheci are be- tween the rivers Prut and Ialpug. In the region of the researched area, altitudes of 70–80 m a.s.l. pre- dominate. The hydrological network is also assigned to the Ialpug river basin, which is poorly developed and it consists of low flow rivers, some of which are partially or completely dry in summer. In the eastern part at a distance of about 1.5 km from the Balabanu sector is the Taraclia accumulation lake which is lo- cated at the Ialpug River.

8 Improvement of GW monitoring network

The altitude of the well pithead will be +70 m a.s.l.. The coordinates in the MOLDREF-99 system are: X - 213208.87; Y - 91683.79 (Figure 2). The depth of the well will be 15 m. The well is intended for monitoring of the Pliocene-Pleistocene groundwater body MDDBSGWQ220.

3.1.3 Petrunea village

From a geomorphological point of view, the sector envisaged for drilling the monitoring well is within the limits of the Plain of Cubolta Inferior Steppe which occupies the upper part of the Raut river basin, a plain also known as the Balti Plain. The relief represents a weakly fragmented plain of valleys with an average altitude of 160 m a.s.l., a maximum altitude between 200–235 m, and a minimum altitude of 70–80 m a.s.l.. Among the modelling processes are the surface erosion, less frequently the torren- tial one and the landslides. The hydrological network in the region of the working area is represented by the Glodeanca river with a length of 30 km, which flows at a distance of approximately 4.4 km from the working area. 17 tribu- taries river flow into the, of which one tributary originates at a rather insignificant distance from the working area. The altitude of the well pithead will be at 163 m a.s.l.. The coordinates in the MOLDREF-99 system are: X - 138126.7; Y - 290557.1 (Figure 3). The depth of the well will be 15 m. The well is intended for monitoring the groundwater body of the middle Sarmatian (lower Codru sub formation) MDPRT- GWQ510.

9 Improvement of GW monitoring network

Figure 1: The location of the monitoring well in Congaz. Scale 1:25 000

10 Improvement of GW monitoring network

Figure 2: The location of the monitoring well in Balabanu. Scale 1:25 000

11 Improvement of GW monitoring network

Figure 3: The location of the monitoring well in Petrunea. Scale 1:10 000

12 Improvement of GW monitoring network

3.2 Geological Structures

3.2.1 Congaz and Balabanu

As the Congaz and Balabanu working areas are at a distance (on the straight line) of about 15 km, the geological structure of these two sectors is similar (Figure 4 and Figure 5). Tectonically, the researched region of working areas Congaz and Balabanu is within the limits of the Predobrogene Depression, which has an extension beyond the Prut and coincides with the Barlad Depression. Within the territory of the Republic of Moldova, the Predobrogene Depression is delimited from the northern part by the Ciadir-Lunga Fault and in the southern part by the Cahul-Ismail Fault. In the south-western direction, the slow sinking of the crystalline foundation and the thickness of the sed- imentary rocks increases. The rocks of Archaic, Proterozoic, Paleozoic and Cainozoic age take part in the geological composition of the researched territory. For the description of the geological structure of the working areas, it is considered sufficient to present only the Quaternary formations (Pleistocene, Holocene). The Pleistocene (AII) formations are subdivided into the Lower, Middle and Upper Pleistocene. Genet- ically is distinguished alluvial, alluvial-diluvia, eluvia, diluvia eluvia-diluvia deposits. The Lower Pleistocene subdivision A II1 includes the deposits of terraces 6th and 5th of the Prut River. The deposits of these terraces are highlighted in independent formations. The Slobozia Mare formation is composed of the deposits of the 6th terrace of the Prut River, which is divided into two lower and upper sub formations. The lower sub formation is presented from the bottom up by the following deposits: pebble 1 m, gravel 1.3 m. The absolute elevation of the terrace base is +20 to + 22 m a.s.l.. The upper sub formation is represented from bottom to top by: sands of various granulations, with thin horizontal interlayers of gravel, then are placed horizontally layered aleurolite. Above, there are overburden sediments represented by stratification of fossil soils, sandy loam and loam up to 10.5 m thickness. Absolute elevation of the overlying bed of the upper sub formation is + 65 to + 70 m a.s.l.. The Middle Pleistocene subdivision AII2 includes alluvial, alluvial-diluvia, estuary and lacustrine de- posits of the 4th to 3rd terraces of the Prut River and its tributaries. The deposits of the 4th terrace of the Prut River are known under the name of the Giurgiulesti formation. The Giurgiulesti formation is divided into the lower and upper sub formation. The lower sub formation is presented from the bottom up by the following deposits: coarse-grained sands, horizontally layered, gray with pebbles up to 1-2 cm in size, the thickness is 2 m. Above are placed fine-grained sands, with cross-stratification, the thickness is 1.5 m. Then followed by the clays with a thickness of 2 m. Upper sub formation (bottom to top): gravel stone 1 m, fine-grained sands 1.5 m, aleurolite 1.2 m, granular clays 0.9 m and aleurolite 1.2 m. Above there are the overburden deposits represented gen- erally by sandy clays. The Reni formation includes deposits of the 3rd terrace of the Prut River, the absolute elevation of the surface terrace is + 18 tp + 20 m a.s.l., and the terrace base is at + 3 to + 6 m. The terrace deposits consist of fine-grained, horizontally layered sands, aleurolite with fine-grained sand interlayers. Above there are the overburden sediments represented generally by loess. The Upper Pleistocene subdivision AII3 includes the deposits of terraces 2nd and 1st of the Prut River and its tributaries. The deposits of these terraces are found in independent formations.

13 Improvement of GW monitoring network

The Cahul formation consists of the deposits of the 2nd terrace of the Prut River, presented from bot- tom to top by: gravel deposits with 0.8 m, aleurolite 1.8 m, sands with pebbles 2 m, sand and aleurolite interlayers 2 m and they are covered with sandy clays. The Leova formation consists of the deposits of the 1st terrace of the Prut River, the absolute elevation of the terrace surface is at +43 m a.s.l., with the terrace base at + 4 m. The base of the terrace is placed on the compact, viscous clays of the middle Sarmatian. The Leova formation is divided into the lower and upper sub formation. The lower sub formation is represented by yellowish quartz sands with aleurolite interlayers (0.2-0.5 m). The sands contain gravel composed of sandstone, quartz. These deposits were opened in the interval between 24 and 13 m. The upper sub formation was opened in the interval between 13.8–1.8 m. The absolute elevation of the terrace base is at + 2 to +5 m, and the terrace surface is at + 6 to + 7 m a.s.l.. It consists of sandy aleurolite. Above, there are overburdens sediments, lithologically represented by heavy, medium, light sandy clays, clayey sands with interlayers of fossil soils.

Figure 4: Geological map of the researched territory of Congaz. Scale 1:50 000

14 Improvement of GW monitoring network

alluvial deposits in river meadows alluvial-diluvia deposits at the bottom of valleys undifferentiated Upper Pliocene and Holocene diluvia deposits undifferentiated eluvia-diluvia deposits of the Upper Pliocene and Holocene undifferentiated diluvia-eluvia deposits of the Upper Pliocene and Holocene alluvial deposits of 1st terrace alluvial deposits of the 2nd terrace alluvial deposits of the 3rd terrace alluvial deposits of the 4th terrace alluvial deposits of the 5th terrace alluvial deposits of the 6th terrace eluvia deposits

Project monitoring well

Figure 5: Geological map of the researched territory of Balabanu. Scale 1:50 000

15 Improvement of GW monitoring network

3.2.2 Petrunea village

Tectonically, the investigated region of the working area Petrunea is within the limits of the Moldavian Plate, which is a component part of the Eastern European Platform. In the geological structure of the platform two geological-structural units are highlighted: the crystalline foundation and the sedimentary cover (Figure 6). The crystalline foundation consists of rocks of Archaic - Early Proterozoic age (AR – PR1), and the sedimentary cover is composed of rocks of Rifean, Vendian, Silurian, Cretaceous, Neogene and Qua- ternary ages. For the description of the geological structure of the working area, it is considered suffi- cient to present only the Sarmatian (Neogene) and Quaternary formations. The deposits of the Sarmatian stage are discordantly placed on the deposits of the Badenian stage, which within the limits of the working area are presented by the lower Sarmatian substage - N1s1 and the middle Sarmatian substage - N1s2. The lower Sarmatian substage is represented by carbonate rocks. The deposits of the Middle Sarmatian within the investigated territory are developed everywhere. Paleontologicaly, the formations of the middle Sarmatian are divided into the lower (N1s2kd1) and middle (N1s2kd2) sub formations. Within the limits of the working area, only the lower Codru sub for- mation is widespread. Lithological, these deposits are divided into two packets of layers: the lower layer package with clay and the upper layer package with sandy-clay. The package of lower layers consists of compact clays gray, dark gray, bluish – gray colour, with a thickness that varies depending on the shape of the land from 48 to 90 m. The upper layer package in the section consists of the following formations (bottom to top):  Feldspar-quartz sands, fine-grained, gray-yellow colour, with interlayers of clay and sandstone. The thickness of the state is 18 m.  Clays with horizontal stratification, gray colour with powder of aleurolite along the planes of lay- ers. The thickness of the state is 12 m.  Feldspar-quartz sands, fine-grained, light gray colour, with thin interlayers of brown clay. The thickness of the state is 26 m.  Clays with horizontal stratification, gray, gray-blue colour, with thin interlayers of fine-grained sand. The thickness of the state is 28 m. Depending on the absolute elevations of the land surface, the thickness of the deposits in the lower Codru sub-formation varies from 12 to 82 m. The deposits of the middle Sarmatian are covered by eluvia, eluvia - diluvia, diluvia deposits of Qua- ternary system, and are represented by brown-yellowish and yellowish sandy clays, and are character- ized by different indices of plasticity. The thickness of the sandy clays is homogeneous over the entire researched surface.

16 Improvement of GW monitoring network

10 3 a N2 ak3-ap1 upper stage Akceagâlian - lower stage Apsheronsk, 10th terrace of the Prut River 2 N1s2kd1 The Middle sub-formation of Codru 1 N1s2kd1 The Lower sub-formation of Codru

N1s1 Lower Sarmatian sub-stage

Projected monitoring well Figure 6: Geological map of the researched territory Petrunea. Scale 1:50 000

17 Improvement of GW monitoring network

3.3 Hydrogeological Conditions

Groundwater is present in almost all stratigraphic divisions, identified within the region the of working areas, forming a unique hydraulic system which is differentiated into several groundwater bodies, di- vided from each other by layers of impermeable rocks.

3.3.1 Congaz and Balabanu

As the Congaz and Balabanu working areas are at a distance (on the straight line) of about 15 km, the hydrogeological condition of these two sectors is similar (Figure 7 and Figure 8). Groundwater from the Pliocene-Pleistocene alluvial and lacustrine-alluvial deposits (a, laA I-II) are united in a single aquifer complex due to similar distribution and feeding conditions, the same lithologi- cal composition of aquifer rocks and the same chemical composition of stored water. The aquifer is attributed to the permeable deposits of the I-X terraces of the Prut River and its tributaries. Water-bearing rocks are represented by sandy clays, clayey sands, mixed-grained sands pebbles and gravel. The deposits occur horizontally or with a slight inclination according to the base of the terraces. The thickness of the aquifer rocks varies from 0.5 to 15 m, but in general between 1 and 5 m. On most of the investigated territory, the deposits of the Prut river terraces are placed on the clay-sand deposits of the Cahul or Codru formations. The abundance of water in the terrace deposits is closely related to the lithology of the aquifer rocks, with the degree of permeability and saturation of the rocks that make up the base of the terraces. The depth of groundwater generally varies from 0.0 to 10 m. Groundwater is free of pressure. In some places, locally, groundwater with pressure is detected; the pressure of the aquifer raises the level of groundwater above the aquifer cover by 0.5 - 3 m. The abundance of water in the aquifer is reduced. The debit rates of the springs do not exceed 0.1 l/s, generally varying between 0.01-0.5 l/s, and the debit in the wells that capture this aquifer is 0.001-0.1 l/s, with a decrease of groundwater level of 1.0- 6.0 m. According of chemical composition, the most common waters are hydrocarbonate-sulphate or sul- phate-hydrocarbonate, of mixed cationic composition, there is an increased content of sulphates (80 mg/l village up to 7,089 mg/l village). The high content of sulphates often leads to exceeding the permissible sanitary norms regarding the pH value of water; for most parts the water is neutral, rarely less alkaline. Freshwater in this region is quite rare; mainly groundwater has increased mineralization (from 0.7 to 5 mg/l). The waters are hard and very hard. The Pliocene-Pleistocene groundwater recharge area coincides with its distribution area. The main recharge of groundwater is due to the infiltration of atmospheric precipitation and also due to the drainage of groundwater from the eluvia-diluvia deposits located above and from the sand-gravel de- posits of Cahul and Codru formations. Source of recharge - drainage of groundwater from Pliocene- Pleistocene deposits is unstable and inhomogeneous according to the regime and quality of water. The regime of the aquifer depends significantly on the seasonality and the amount of atmospheric precipitation. The amplitude of groundwater level fluctuations varies between 0.2 - 3.0 m. The waters of this aquifer, due to the deficiency of other better sources, are often used by local popu- lation for household and drinking purposes through shallows wells and springs, however, they cannot be used for centralized supply due to low water abundance, increased hardness, chemical composi- tion mixed, and possible contamination of water.

18 Improvement of GW monitoring network

Figure 7: Hydrogeological map of the researched territory in Congaz. Scale 1:50 000

19 Improvement of GW monitoring network

GW from Holocene alluvial deposits

GW with sporadic spread from the Upper Pleistocene eluvia-diluvia deposits

GW from the Pliocene and Pleistocene eluvia deposits

GW from the Upper, Middle and Lower Pleistocene alluvial deposits

GW from the Upper Pliocene alluvial deposits

GW from the Pontian deposits

GW with sporadic spread from Pontian deposits

GW with sporadic spread from undifferentiated deposits of Upper Sarmatian and Meotian

Projected monitoring well Figure 8: Hydrogeological map of the researched territory Balabanu. Scale 1:50 000

20 Improvement of GW monitoring network

3.3.2 Petrunea village

Groundwater from the deposits of the Middle Sarmatian, the lower Codru sub formation (N1s2kd1), is stored in fine-grained sand interlayers from the formation of clays and sandy clays. The thickness of the aquifer interlayer varies from 0.67 to 10 to 12 m. In general, the average thickness of the aquifer interlayer is 3.6 m. In the area, the water-bearing rocks are covered by compact, unaltered clays of Middle Sarmatian age. At the top of the area there are eluvia, eluvia-diluvia deposits and landslide deposits which are composed by a mixture of different varieties of rocks. According to the conditions of the aquifer, the groundwater is without pressure. The depth of groundwater is 10-15 m. The groundwater level has an uneven surface. The abundance of water is very low. The debit in wells in the region varies from 0.001 l/s to 0.042 l/s, with a decrease in level from 1.81 to 5.88 m. Water abundance and filtration properties of aquifer rocks, calculated according to data obtained from experimental pumping from well no. 301 from the Petrunea village region, are as follows:  Debit - 1.04 m3/day (0.012 l/s);  Specific debit - 0.011 l/s; decrease of level - 1.06 m;  Filtration coefficient according to Dupuit's formula - 0.8 m/day; according to Ernst's formula - 0.46 m/day The conditions regarding the abundance of water and the filtration properties of the aquifer rocks were tested only on aquifer interlayers separated from the sandy-clay formation from the lower Codru sub formation of the Middle Sarmatian.

21 Improvement of GW monitoring network

Groundwater from Holocene alluvial and alluvial-diluvia deposits

Groundwater with sporadic spread from Quaternary alluvial deposits

Groundwater with sporadic spread from eluvia-diluvia deposits

Groundwater from the Upper Pliocene alluvial deposits

Groundwater from clayey sand deposits of Middle Sarmatian, Codru sub-formation

Groundwater from the Upper Badenian-Lower Sarmatian deposits

Groundwater from Upper Cretaceous deposits

Outline of the spread of permeable alluvial deposits of the Quaternary and Upper Pliocene

Projected monitoring well

Figure 9 Hydrogeological map of the researched territory Petrunea. Scale 1:50 000

22 Improvement of GW monitoring network

4 QUALITATIVE CHARACTERISTICS OF GROUNDWATER

The criteria for assessing the quality of groundwater are based on the sanitary normative acts in force regarding the quality of drinking water (Government Decision Nr. 934/2 of 24.08.2007).

4.1 Congaz village

Groundwater from deposits of the Upper and Middle Pleistocene, according to the composition of salt ions are attributed to the type hydrocarbons - sulphate magnesium - sodium, with dry residue between 3069 - 3097 mg/l. The waters are moderately saline. The quantitative relations between groundwater salts are presented by the formula: SO 56HCO 26Cl17 M  4 3 . pH 7.3 . O 2.43 . F 1.56 3,5 (Na  K)44Mg43Ca13 2

The content of the main macro elements that form the chemical composition and the type of ground- water falls within the following limits (mg/l): hydrocarbons 774-824, sulphates 1403-1436 and chlorides 316-322 mg/l. The cationic composition is dominated by (mg/l): sodium and potassium (in total) 537- 542; magnesium 272 and calcium 134. Concentrations of nitrates of 34.7-70.72 mg/l and ammonium <0.01 were detected among the dissolved nitrogen compounds. Total iron concentration is 0-0.17 mg/l. The fluoride concentration is 0.78-1.56 mg/l. The waters are very hard, the total German hard- ness of the groundwater is 81.52°. The water is neutral with a pH of 7.3-7.9. In the composition of groundwater microelements, their concentration is as follows (mg/l): copper 0.76, aluminium <0.02 and polyphosphates <0.01. Among the gases dissolved in water were detected: oxygen with 2.43 mg/l and hydrogen sulphide with <0.05 mg/l. The chemical composition of the groundwater from the Pliocene-Pleistocene deposits does not meet the standards of sanitary norms for drinking water due to the concentration of dry residue of 3097 mg/l, (norm 1500 mg/l), chlorides 322 mg/l (norm 250 mg/l ), sulphates 1436 mg/l (norm 240 mg/l), sodium 542 mg/l (norm 200 mg/l), nitrates 70.72 mg/l (norm 50 mg/l), and the value of total hardness with 81.52° dH.

4.2 Balabanu village

According to the chemical composition, the groundwater from the deposits of the lower Pleistocene age, in general, is attributed to the hydrocarbons-sulphate magnesium-sodium type, with a dry residue of 1145 mg/l. The waters are slightly saline. The quantitative relations between groundwater salts are presented by the formula:

HCO3 79 SO410Cl10 M  . pH 8.2 . O2 1.78 . F 4.94 1,7 (Na  K)72Mg20Ca8

The content of the main macro elements that form the chemical composition and the type of ground- water falls within the following limits (mg/l): hydrocarbons 106, sulphates 100 and chlorides with 76.

23 Improvement of GW monitoring network

The cationic composition is dominated by (mg/l): sodium and potassium (in total) 365, magnesium 52 and calcium 35. Among the dissolved nitrogen compounds low concentrations were found, with ni- trates of 16.48 mg/l. Total iron concentration is 0.14 mg/l. A high fluoride content of 4.94 mg/l was marked. The waters are hard; the total hardness of the groundwater is 16.99° German. The reaction of the water is slightly alkaline pH 8.2. In the composition of groundwater micro elements, their concen- tration is as follows (mg/l): copper 0.03, aluminium <0.02 and polyphosphates <0.01. Among the gases dissolved in water were detected: oxygen with 1.78 mg/l and hydrogen-sulphide with <0.05. The waters do not meet the standards of sanitary norms for drinking water due to a sodium concentra- tion of 365 mg/l (norm 200 mg/l) and the value of the total hardness of 16.48 German degrees.

4.3 Petrunea village

Fresh groundwater with a dry residue of up to 1000 mg/l is the most widespread in this area. Accord- ing to the chemical composition, the groundwater from the sand interlayers of the middle Sarmatian age is attributed to the hydrocarbonate-magnesium-sodium type. The sulphate content is up to 315 mg/l, with a maximum permissible concentration of 240 mg/l. The content of chlorine ions, in general, does not exceed the limits of the permissible norms being up to 120 mg/l. The content of nitrate varies within quite large limits. In 80% of the water samples taken from the shal- low wells that capture this groundwater, the nitrate concentration was detected above the maximum permissible norms of 50 mg/l, which indicates an increased degree of groundwater pollution. In most water samples, nitrites and ammonium are missing or their concentration does not exceed the stand- ards of permissible sanitary regulations. Groundwater is neutral with a pH of 6.8-7.3. The value of the total hardness varies between 3.8 - 5.0 mEq/l, characterizing them as soft waters. The micro elements copper, zinc, selenium, beryllium, manganese, molybdenum are absent in most of the groundwater samples. Fluoride content reaches up to 1.2 mg/l. Concentrations of pesticides in groundwater in the middle Sarmatian and Pliocene-Pleistocene aqui- fers were not detected. After completing the drilling of the projected monitoring wells and performing the experimental pumping, it is necessary to take water samples for chemical analysis.

24 Improvement of GW monitoring network

5 SANITARY PROTECTION ZONES

According to the provisions of the “Regulation on the design and operation of sanitary protection areas of water supply sources and aqueducts” (2640-82 of 18.12.1982), and in accordance with Government Decision no. 949 of 25.11.2013 and the norms provided in SNiP 2.04.02-84 (p.10.2) „Water supply. External networks and constructions… ”, Sanitary Protection Areas (SPA) are arranged for the protec- tion of groundwater from different types of pollution, with different degrees of risk compared to pollu- tion factors. Sanitary protection areas consist of three perimeters:  Perimeter I – strict regime of sanitary protection zone.

 Perimeter II - restricted sanitary protection zone.  Perimeter III - sanitary protection zone with observation regime (hydrogeological protection pe- rimeter). Protection zones around water-supply points shall be determined, in order to ensure the preservation and renewal of water resources, as well as to reduce the pollution of water resources to be obtained during the whole exploitation of source of water. Perimeter I is established in order to remove possible or intentional pollution of groundwater from the land surface or from recharge sources of the aquifer. The limits of perimeter I of the sanitary protection zone are determined according to the type of water source: for the use of well-protected groundwater the boundary is established within a radius of 30 m from the well hookup and with a radius of 50 m when using insufficiently protected groundwater. For the three projected monitoring wells, perimeters II and III of the sanitary protection zones will not be calculated. In the region of the investigated areas, the groundwater from sand interlayers of the middle Sarmatian and from the Pliocene-Pleistocene deposits are unprotected. Hence, for the protection of the aquifer from pollution it is necessary that perimeter I has the dimension of a radius of 50 m from the centre of the well hookup. The strict regime of sanitary protection zone shall be determined around the water- supply points, as well as a bacteriological and chemical protection zone.

25 Improvement of GW monitoring network

6 STEPS OF WATER WELL DRILLING

1. Installation of the UGB-IVS drilling rig on the planned sector for drilling the wells, arrangement of the water collector, the sedimentation basin and the circulation system. 2. Preparation of drilling fluid from bentonitic clays and technical water (bentonitic mud). 3. Drilling the "pilot well" with a drill bit with a diameter of ø 151 mm to the projected depth of the monitoring wells as follows: Congaz well: 10 m; Balabanu well: 15 m; Petrunea well: 15 m. 4. Preparation for logging and conducting electrical- gamma logging in the interval: Congaz well: 0–10 m; Balabanu well: 0–15 m; Petrunea well: 0–15 m. 5. Widening out the well with a drill bit with a diameter of ø 245 mm to the projected depth of each well. 6. Preparation for casing and installation of the pipe column and the filter column with string of DN140 R10 to the projected depth of each well. The working part of the strainer is presumably in the intervals of: Congaz well: 6–9 m; Balabanu well: 12–14 m; Petrunea well: 9–14 m. 7. Flushing the well through a check valve - 3.43 installation/change. Dusting sand filter with back- filling of sand and gravel mixture in the interval of: 8. Preparation for cementation and casing grouting by the direct pouring method into the annular space in the interval of: Congaz well: 0–6 m; Balabanu well: 0–12 m; Petrunea well: 0–5 m. 9. Washing the well filter column: 2.28 installation/change. 10. Decolmation of the well: 3.43 installation/change (24 hours). 11. Experimental pumping with a submersible pump to determine the behaviour of groundwater lev- el- 1 day (3.43 installation/change). At the end of the experimental pumping, water samples are collected for chemical analysis. 12. Dismantling the drilling rig. 13. Wellhead cementation and equipment with pipe end and cover. 14. Clogging of the backfilling of sump and circulation system. Note: the installation interval of the filter will be specified after the interpretation of the logs obtained following the coring works.

26 Improvement of GW monitoring network

7 GEOLOGICAL-TECHNICAL SECTIONS OF THE PROJECTED MONITORING WELLS

The following three figures show the profiles of the three wells and details for the well construction.

Figure 10: Well in Congaz village

27 Improvement of GW monitoring network

Figure 11: Well in Balabanu village

28 Improvement of GW monitoring network

Figure 12: Well in Petrunea village

29 Improvement of GW monitoring network

8 LIST OF REFERENCES

1. Bogdanova S.V. „Report on preliminary studies of groundwater, carried out in order to find ad- ditional sources of water supply for the urban settlement. Glodeni MSSR ”. 1972, Moldavian hydrogeological expedition. (in Russian) 2. Panin A.N. Report on the results of preliminary exploration of groundwater for water supply to the villages of Congaz, Cioc-Maidan, , Borogani, region of the MSSR. 1980, South Moldavian hydrogeological expedition (in Russian) 3. Zhuk S.V. Report on the results of preliminary exploration of sulphide mineral waters in the Congaz village of the Comrat region of the MSSR. 1981, Comrat hydrogeological party (in Russian) 4. Gorobchenko L.I. Report on the results of detailed exploration of groundwater for water supply to the village of Congaz. 1982, Moldavian hydrogeological expedition(in Russian) 5. Arabadzhi V.A. Report on the results of preliminary exploration of groundwater for water sup- ply of Taraclia settlement. 1974. Comrat hydrogeological party (in Russian) 6. Novikova V.P. Report on the search for mineral waters in the area of Comrat and Taraclia vil- lage. 1985, Moldavian hydrogeological expedition (in Russian) 7. SNIP 2.04.02-84 „Water supply. Exterior networks and buildings” 8. Sanitary Norms and Rules 2.1.4.027-95 (SaNPiN) 2.1.4. Drinking water and water supply to localities. Sanitary zones for protection of water supply sources and household networks - drinking 9. Drinking water quality parameters. (Annex no. 2 to the Sanitary Norms of drinking water quali- ty. According to the Decision of the Government of the Republic of Moldova no. 934 of August 15, 2007). 10. Government Decision no. 949 of 25.11.2013, for the approval of the Regulation on sanitary protection areas of water intakes.

30 Improvement of GW monitoring network

9 ANNEXES

The officially approved projects of the three monitoring wells.

31 Improvement of GW monitoring network

32 Improvement of GW monitoring network

33 Improvement of GW monitoring network

34 Improvement of GW monitoring network

35 Improvement of GW monitoring network

36 Improvement of GW monitoring network

37 Improvement of GW monitoring network

38 Improvement of GW monitoring network

39 Improvement of GW monitoring network

40

www.euwipluseast.eu