LT LT2300 2300 Venta River Basin District Groundwater bodies (GWB) have been identified on the following assumptions: 1. bodies consist of hydraulically closely connected aquifers – hydrodynamic systems; 2. systems or layers are divided by clearly identifiable confining layers; 3. body boundaries are natural contours of aquifer fracturing or those of water quality; 4. bodies consist of aquifers which are used most intensely; 5. groundwater bodies were adjusted to delineated river basin districts. The groundwater bodies were identified using the digital database of the Lithuanian Geological Survey, topographic and geological maps as well as material of various geological and hydro-geological research, and relevant literary sources. The identification of the bodies was carried out taking into account the conditions of occurrence of groundwater as well as lithological, hydro-dynamical and hydro-chemical differences of the aquifers, and use of groundwater in the body in question. Ammonium 3 3 mg/l 75 National Chloride 350 250 mg/l 100 In natural geochemical anomalic zones existing data does not indicate impact of water abstraction on upward trend National Sulphate 500 250 mg/l 100 In natural geochemical anomalic zones existing data does not indicate impact of water abstraction on upward trend National Trichloroethylene 40 10 µg/l 75 National Nitrates 50 50 mg/l 75 National Arsenic 10 10 µg/l 75 National Cadmium 6 5 µg/l 75 National Lead 75 25 µg/l 75 National Mercury 1 1 µg/l 75 National The treshold values were derived acoording to the procedure set out in the Annex II of the Groundwater directive. Three different criteria were applied: 1. For part of GWB's used for drinking water supply - usage criteria (Hygienic norm (drinking water standard, lower value of TV range); 2. for Cl, SO4 usage criteria and background values for hydrochemical anomalies, NH4 - background values; 3. For part of GWB's where interaction with terrestrial ecosystems and surface water occur - environmental criteria EQ (Upper value of TV's range) are relevant. Sulphates and chlorides are naturally occurring substances which worsen groundwater quality in some limited regions of Lithuania. Detailed analysis of hydrochemical anomalies revealed that transit zone between good and poor groundwater (as drinking water) quality is very narrow. Area of anomalies delineated based on background TV’s do not differ significantly from those on TV from drinking water standard. TV's correspond to drinking water standard (Hygienic norm HN 24:2003) for groundwater from the main GWB aquifers used for public water supply and to Environmental standard (EQ) for shallow part of GWB within entire country. The groundwater chemical status was carried out according to criteria approved by the Order of the Minister of Environment No D1-172 of 2007-03-23 on General Requirements on Criteria for Assessment of the Status of Groundwater Bodies. Mathematical modelling was used: 1. To estimate available groundwater resources; 2. To evaluate impact of groundwater abstraction on surface water ecosystems; 3. To assess groundwater quantinative status. The assessment was carried out following requirements set out in the WFD Annex II. Trend assessment at individual monitoring points within a body or a group of bodies of groundwater status was carried out according to criteria approved by the Order of the Minister of Environment No D1-172 of 2007-03-23 on General Requirements on Criteria for Assessment of the Status of Groundwater Bodies. Identification of groundwater bodies subject to a reversal of significant and sustained upward trend was carried out according to criteria approved by the Order of the Minister of Environment No D1-172 of 2007-03-23 on General Requirements on Criteria for Assessment of the Status of Groundwater Bodies. Starting point for trend reversal is set at 75% of stardard or threshold value for GWD Annex 1 parameters except for chlorides and sulphates in natural geochemical anomalic zones. In natural geochemical anomalic zones existing data does not indicate impact of water abstraction on upward trend for chlorides and sulphates. Starting point for trend reversal for chlorides and sulphates is set at 100% of the threshold value. Mathematical modeling was used to assess impact of contaminated sites on groundwater status. Assessment of existing information indicates only local pollution and existing small scale plumes from contaminated sited do not expand and do not deteriorate the chemical status of groundwater status. Joint bilateral programmes for monitoring of chemical status and level of groundwaters along the border was established with Latvia. Chemical and quantitative status of groundwater is good in the transboundary water body and groundwater monitoring data indicates no upward trend and necessity for establishment of threshold values. Meetings with Latvian Ministry of Environment were held to coordinate establishment of objectives for transboundary groundwaters. Further characterisation was carried out according to the requirements of the WFD Annex II. Lithuanian Geological Survey http://www.lgt.lt/ Environmental Protection Agency http://vanduo.gamta.lt/cms/index Available groundwater resources are not exceeded by the long-term annual average rate of abstraction Average concentration of nitrates in shallow groundwater in arable land areas does not exceed 16,88 mg/l, in urban areas – 45,14 mg/l., i.e., it does not exceed drinking water criteria (50 mg/l for nitrates). In deeper aquifers, where anoxic environment dominates, concentration of nitrates is negligible Only traces of pesticides in some point source pollution cases were detected, no map was created Maps of ammonia and phosphate occurence in shalow groundwater were compiled. Average concentrations of ammonia were at maximum (2,44 mg/l) in certain urban areas of the greater cities of Lithuania. Drinking water standard limit (0,5 mg/l of NH4) also exceeds average concentrations of ammonia in certain agricultural areas. But only in few cases ammonia is an indicator of fresh groundwater pollution – usually it is a product of nitrate-nitrite-ammonia transformations in poorly aerated shallow aquifers. Ammonia in deep aquifers is a product of similar nitrate-nitrite-ammonia transformations, or it is a product of geogenic origin. Normally phosphates are absent even in shalow groundwater, because PO4, entering groundwater, is rapidly scaled by Ca in almost unsoluble form No significant and sustained upward trends are observed in GWB. Transboundary coordination with Latvia is limited to joint monitoring programme of aquifers. Meetings with Latvian Ministry of Environment were held to coordinate presence of significant and sustained upward trends for transboundary groundwaters. Assessment of point pollution pressures on the quality of the groundwater bodies was carried out in line with requirements of CIS guidance No. 18 on Groundwater Status and Trend Assessment. The pressure was assessed by analysing the long term groundwater monitoring data, using mathematical modelling techniques, mapping and expert judgment. The modeling covered assesment of point source pollution on shallow groundwater, impact of shallow groundwater on status of surface water and status of confined aquifers Environmental Protection Agency http://vanduo.gamta.lt/cms/index Assessment of diffuse pollution pressures on the quality of the groundwater bodies was carried out in line with requirements of CIS guidance No. 18 on Groundwater Status and Trend Assessment. The pressure was assessed by analysing the long term groundwater monitoring data, using mathematical modelling techniques, mapping and expert judgment. The modeling covered assesment of diffuse pollution on shallow groundwater, impact of shallow groundwater on status of surface water and status of confined aquifers Assessment of groundwater abstraction pressures on the status of the groundwater bodies was carried out in line with requirements of CIS guidance No. 18 on Groundwater Status and Trend Assessment. The pressure was assessed by analysing the water accounting data from water abstration points (more than 10m3 per day), long term groundwater monitoring data. Assessment was carried out using mathematical modelling techniques, mapping and expert judgment. Impact of water abstration was assessed on the scale of groundwater body. Impact to groundwater resources, impact on surface water ecosystems and impact on water quality (intrusions) was assessed Groundwater monitoring annual report http://www.lgt.lt/uploads/1193124579_MONITORINGAS_2006.pdf Environmental Protection Agency http://vanduo.gamta.lt/cms/index Not applicable Assessment of intrusions on the status of the groundwater bodies was carried out in line with requirements of CIS guidance No. 18 on Groundwater Status and Trend Assessment. Assessment of salt water intrusions included delineation and mapping of natural anomalic zones. Within the natural anomalic zones further characterisaion was carried out. Long term groundwater monitoring data and trend analysis was used for assessment of significance of the impacts of intrusion and water abstrations within the natural anomalic zones Not applicable 'There are no RBD-scale significant impact on shallow groundwater, associated with diffuse source pollution: this pollution did not exceed drinking water criteria (50 mg/l for nitrates, 0,5 mkg/l for the pesticides).

Today we have no precise information on presence or absence of fresh/saline groundwater in certain areas of GWB . In cases, when groundwater monitoring data is available, its quantity and quality data is often not sufficient for groundwater quality trend identification. Sometimes this data is not trustworth because monitoring company or laboratories were not trustworth. Available groundwater quality data was critically analysed, many groundwater quality maps and hydrochemical sections were produced for better understanding of groundwater quality formation in named GWB. Aiming to reduce available data gaps and uncertainties associated with saline water intrusion, more dense monitoring network in the GWB is proposed.

No exemptions applied. No deadlines are set (no exemptions applied). Coordination with Latvia was limited to join groundwater monitoring program. Chemical and quantitative status of groundwater is good in the transboundary water body and there is no necessity for use of exemptions.