1. Ljubljana, 10.09.2004 | Slide 1 Groundwater Quality Assessment Determination of chemical status and assessment on individual sites Austrian experience in implementation of Directive 2000/60/EC requirements Andreas Scheidleder Umweltbundesamt – Austria andreas.scheidleder@umweltbundesamt.at

2. Ljubljana, 10.09.2004 | Slide 2 General Remark The risk (quality) assessment is still in process and under discussion. No procedure and no significance level is fixed. Regulations on EC level are still under discussion.

3. Ljubljana, 10.09.2004 | Slide 3 Risk (Quality) Assessment Development of national guidance document Risk assessment on the basis of existing data (according to WG 2.1 IMPRESS) Well-founded assumption that the current network was designed to be a representative network which was continuously adapted Development of reporting structure appropriate maps and tables Tested and discussed in a pilot study Preliminary assessment provided to Counties for comment, amendment and for approval

4. Ljubljana, 10.09.2004 | Slide 4 Legal Background Federal Water Act Hydrography Act Ordinance for Water quality Monitoring Ordinance for Groundwater Threshold Levels

5. Ljubljana, 10.09.2004 | Slide 5 Monitoring and Network Monitoring ~ 1800+250 sites (slight changes) 4 times per year ~ 100 parameters (in 3 blocks) Quality Assurance Programme Publication of data and information Network adaptation until end 2005

6. Ljubljana, 10.09.2004 | Slide 6 Risk assessment 1. Characterisation

7. Ljubljana, 10.09.2004 | Slide 7 Risk assessment 2. Assessment of network

8. Ljubljana, 10.09.2004 | Slide 8 Risk assessment 2. Assessment of network Preliminary assessment - Federal Level Groundwater bodies - Representativity Index Ru Groups of groundwater bodies - Thiessen polygons Final assessment - County Level Local expertise (e.g. hydrogeology etc.) Network assessed as representative partially representative not representative

9. Ljubljana, 10.09.2004 | Slide 9 Risk assessment 2. Assessment of network Cl … Classsites < 33 <= sites < 55 <= sites < 10sites >= 10 Ru < 50 %Cl 4 > 0 % 50 <= Ru < 70 Cl 4 = 0 % Cl 3 > 50 % Ru >= 70 % Cl 4 = 0 % Cl 3 <= 50 % Deviation classes from average Network representative Cl 4 … > 400% Network partially representative Cl 3 … 200-400 Network not representative

10. Ljubljana, 10.09.2004 | Slide 10 Risk assessment 2. Assessment of network Local expertise on County level over-rules preliminary assessment at Federal level considering Art 5 Analyses e.g.: GW-flow direction, Point and diffuse sources of pollution, Soil characteristics, Overlying strata Sampling site density and spatial distribution Hydrogeological representativity

11. Ljubljana, 10.09.2004 | Slide 11 Risk assessment 3. Assessment of quality data

12. Ljubljana, 10.09.2004 | Slide 12 Risk assessment 3. Assessment of quality data Quality Assessment Method Representative Network National criteria Not Representative Network Analogy conclusion from impacts - Modelling approach Partially Representative Network Combined approach - Average of national criteria and modelling Trend assessment Method Upward trend exceeding 75 % of parametric value (DWD)

13. Ljubljana, 10.09.2004 | Slide 13 Risk assessment 3. Assessment of quality data Relevant Parameters only those parameters where a national threshold value and a parametric value in the drinking water directive (DWD) is available: Nitrate Atrazin Desethylatrazin Cadmium Bentazone Focusing on the GW-body level only !

14. Ljubljana, 10.09.2004 | Slide 14 Representative Network National quality assessment criteria Laid down in the Ordinance for Groundwater Threshold Levels GW-body is at risk when in the assessment period (2 years) at least 50 % (or 30 % - still in discussion) of sites are endangered. A site is endangered when arithmetic mean exceeds threshold value. (excluded: sites with geogen background) At least 5 values per site At least 5 sites per GW-body

15. Ljubljana, 10.09.2004 | Slide 15 Trend assessment Statistical significant upward trend Risk if trendline exceeds 75% of the parametric value of the DWD (WFD, Art. 17) Assessment period 1997–2002 (min. 5 years) Minimum 3 sites per body Average of average Quarterly aggregated data Treatment of values < LOQ

16. Ljubljana, 10.09.2004 | Slide 16 Not Representative Network Modelling approach Best possible cause-effect-relationship between influencing factors and GW-Quality Risk assessment based on analogy conclusions from influencing factors to GW-Quality At groupes of GW-bodies without sites and where the monitoring network is not representative Weighted multifactoral Regression Estimation of GW-body mean

17. Ljubljana, 10.09.2004 | Slide 17 Modelling approach Influencing factors about 150 influencing factors

18. Ljubljana, 10.09.2004 | Slide 18 Modelling approach Influencing factors ~ 150 factorsbodyMuni.site CORINE Landcover, X r500m Precipitation, GeologyX Share of soil permeability (1-3) (FAO) X X Inhabitants, cattles X Agricultural statistics 1999 X Impacts on water by land use activity (1-5)X Type of site, depth to GWX Distance between site and next contaminated site (oil, CHC, Metals) X Possible influences around the siteX

19. Ljubljana, 10.09.2004 | Slide 19 Modelling approach Influencing factors about 150 influencing factors Significance - 25-35 Interpretability Relevance - 90 Stability & Plausibility influencing factors 10 influencing factors

20. Ljubljana, 10.09.2004 | Slide 20 Modelling approach Influencing factors 10 influencing factors Geology, precipitation and altitude Soil storage capacity Impacting/reliefing factors from agricultural statistics (e.g.: barley, root crops, maize) Impacting/reliefing factors from CORINE Landcover (e.g.: agriculture, vineyards)

21. Ljubljana, 10.09.2004 | Slide 21 Modelling approach Comparison between monitored and predicted values (nitrate)

22. Ljubljana, 10.09.2004 | Slide 22 Partially Representative Network Combined approach If monitoring network is only partially representative: Average of national criteria and modelling

23. Ljubljana, 10.09.2004 | Slide 23 Outlook – EC level Groundwater Directive still under discussion - Nothing fixed!! Expert meeting of Council Environment Group on 1st Sept 2004 Many countries against “one out all out” – to be discussed Assessment on site level triggering risk – to be discussed Values < LOQ  ½ LOQ – to be discussed Boarder points should be fixed – flexibility with countries Length of time series for trend assessment Aggregation for trend assessment still open Consideration of background for assessing environmental significance (75% - trend) – to be discussed Methodology for establishing threshold values (BRIDGE) Still Discussion NOT Decision

24. Ljubljana, 10.09.2004 | Slide 24 Outlook – EC level Summary of discussion by Presidency forwarded to Council Environment Group Open discussion in working party on environment Mid Oct – Start of discussion for common methodology on establishing threshold values WG 2C: Developing guidelines for status and trend assessment when GWD is legally binding

25. Ljubljana, 10.09.2004 | Slide 25 Groundwater Quality Monitoring and Assessment (chemical status and assessment on individual sites) Austrian experience in implementation of Directive 2000/60/EC requirements Andreas Scheidleder Umweltbundesamt – Austria andreas.scheidleder@umweltbundesamt.at