## 4 Results and Discussion  
The impact of salinization is most felt at the Boljkovac pumping stations and at the Golubinka karst spring, and they are located closest to the seacoast. The impact of salinization on the Jezerce pumping station is much smaller, while on Bokanjac this impact is the smallest as it is located furthest from the seacoast. Therefore, this basin can be divided into the coastal zone where the impact is greatest (Boljkovac and Golubinka) and the inner zone of aquifer where this impact is much smaller (Jezerce and Bokanjac). At the Boljkovac and Golubinka pumping stations, an increase in salinity occurs during rainy periods when the mixing zone of salt and fresh water expands due to large inflows from the hinterland. The Jezerce pumping station behaves very similarly, but this impact is much smaller and the impact of pumping during the summer dry periods is also felt, which causes a limited conical uplift of salinity from the deep part of the aquifer. At the Bokanjac pumping station (B-4 and B-5), rainy periods do not cause problems with salinization, but excessive pumping affects slightly higher concentrations of chloride and sulphate. Average precipitation in the catchment area for the period 1961-2018 is 911.2 mm [13]. Hydrological years 2017/18 and 2018/19 during which operational monitoring was carried out fall into average years according to the amount of precipitation (980 mm and 852 mm) [13]. In the Boljkovac water intake, the greatest salinization occurs when larger waters appear. Comparison diagrams of chloride and sulfate concentrations with the pumping volumes for each water well are given in Figures 5-8. Figure 5: Comparison diagram of chloride, sulfate concentrations, and pumping volumes for Golubinka well. Figure 6: Comparison diagram of chloride, sulfate concentrations, and pumping volumes for Boljkovac well. Figure 8: Comparison diagram of chloride, sulfate concentrations, and pumping volumes for Bokanjac well (B-4 and B-5 wells). Figure 7: Comparison diagram of chloride, sulfate concentrations and pumping volumes for Jezerco well. From given comparison diagrams (Figures 5-7) it can be seen that on Boljkovac, Golubnika, and Jezerce water intake, the amount of pumping has no significant impact on the rise of the chloride and sulfate concentrations. Although given analysis shows the certain association of pumping, water levels, and increased chloride content. This relationship manifests itself by the raise of the water pumping and chloride concentrations in smaller quantities. It is possible that in conditions when chlorides do not exceed the MAC condition, the amount of pumping effect on freshwater overpressure in marginal parts of the aquifer and saline seawater enters the source zone. Both B4 and B5 at the Bokanjac well exhibited a connection between pumping volumes and chloride and sulfate concentrations, as seen in Figure 8. Additionally, it can be seen that higher values of chloride and sulfate concentrations appear in summer months when pumping volumes are higher due to the higher consumption caused by tourism season. At the time of maximum measured concentration chloride on B-5, the well was pumped at 245 L/s and, by reducing the amount of pumping to 120 L/s, reduced the chloride concentration to normal values of about 25 mg/L [13]. There are many ways of investigation regarding the flow dynamics processes, transport, and distribution of particles in coastal zones that found preferential paths for seawater intrusion in coastal aquifers, but most of them are based on mathematical models [30; 31]. Coastal reservoirs contribute to the alleviation of water shortages in coastal zones, and their water quality is greatly affected by inland groundwater flow and tides. [32] Some studies take into consideration water/salt exchange processes between the coastal reservoir and its adjacent aquifers and took deep pools and tidal forcing into consideration [33].