1. Recommendations for sustainable management of transboundary hydrogeothermal resources at cross-border pilot areas Bad Radkersburg-Hodoš Area (Slovenia-Austria-Hungary) Andrej Lapanje and the TRANSENERGY team Final Event of project TRANSENERGY – Transboundary geothermal energy resources of Slovenia, Austria, Hungary and Slovakia Vienna, 24. June 2013

2. 1)Aims of research 2)Overview of past knowledge and utilisation status 3)Pilot area conceptual models 4)Geothermal potential assessment - natural state and different production scenarios - 5)Current vs. proposed management and utilisation - recommendations on transboundary management - Content

3. Geographical overview Area (SI)Area (AT)Area (HU)Total Pilot area (km 3 )8316665822,079 Pilot area (%)403228100 SettlementsInhabitants Szentgotthard8,839 Jennersdorf4,207 Gornja Radgona3,115 Lenart3,078 Radenci2,187 Bad Radkesburg1,326 Alltogether more than 110,000 inhabitants Main industry: - Agriculture - Machine industry - Tourism

4. Scope of investigation: Geothermal system in the Preneogene basement rocks within the Raba fault zone in the Radgona – Vas tectonic halftrench Scientific What is the real extent of the Prenogene geothermal aquifer? Does this aquifer have an active recharge and how are the recharge mechanisms working ? Where the recharge area is? Management Do the already drilled boreholes in the Prenogene geothermal aquifer hydraulically interfere and to what extent? What kind of measures is needed to reach sustainable utilisation? How much energy (and mass) it is possible to extract in a sustainable way in future? Aims of Research

5. Structural overview

6. Previous status of knowledge Potential mechanism of recharge (Domberger & Schreilechner 2007) Dilema (Suete, Common project proposal, 2011): Recharge from infiltration in Bakony Mts. Wide spreading percolation from overlaying sediments Synthesis: NANUTIWA, 2005 TRANTHERMAL, 2008 Singular projects: - oil and gas, -geothermal, -underground gas storage

7. Oveview of utilisation Granted quantity (m 3 )Actual production (m 3 )Geothermal doublet Bad Radkersburg700,000No available data BenediktIn application65,000in consideration KorovciNo consession0planned No natural discharge features No observable changes in production and quality in Benedikt No reported changes in production and quality in Bad Radkersburg Location Water wells Total yield Outflow temp. Use Bad Radkersburg 2 wells22 l/s~78°C Balneological and energy use Benedikt1 well5 l/s72°CDistrict heating Korovci1 well~20 l/s80°C Not in use / doublet in preparation

8. Utilization challenges The water is technically hard to use: -high scaling potential Current mitigation: -use of inhibitors -periodical acid flushing Solution for future (BAT): -closed system with reinjection (geothermal doublet)

9. Geological setting NW border of the Mura-Zala neogene sedimentary basin fractured Mz carbonates and Pz metamorphic rocks - Raba fault zone deepening towards NE to over 4000 m

10. Hydrogeological and geochemical setting The chemical composition of thermal water in Bad Radkersburg and Benedikt is similar Permeability is highly anisotropic, double porosity principle and depends on the structural position within the fault zone The recharge from HU is unlikely as: –observed hydraulic heads in HU are lower than in Benedikt, Bad Radkersburg and Korovci – –mineralisation of water in thermal karst (east of the pilot area) is very high in comparison to Benedikt - Bad Radkersburg area

11. Natural geothermal conditions Temperature in the Preneogene basement rises towards NE Convective flow cell in Benedikt with supposed base at about 2,000 m Locally enhanced permeability of fissured rocks in the geothermal aquifer

12. Natural potential of the Preneogene aquifer Area (SI)Area (AT)Area (HU)Total area Aqufier (km 2 )3494873470 Aquifer (%)741016100

13. Methodology - Numerical modelling Coupled flow and heat transfer FEFLOW code Two distinctive lithologies The Raba fault zone

14. Geothermal potential due to different production scenarios (reinjection or no reinjection) Production without reinjection: Hydraulic depression would reach Bad Radkersburg only if very high abstraction rates or preference flow paths were present. Production with reinjection - geothermal doublet Korovci : Potential cool-down effects of the reinjected water front, i.e. thermal breakthrough is unlikely after 50 years in the pumping regime 20 l/s and thermal regime 80 °C / 35 °C.

15. Current management Current management practiceBad Radkersburg (AT)Benedikt (SI) Operating pressure or water level [bar or m]ContinuouslyNo Water meter (total extraction)ContinuouslyOccasionaly Outflow temperature [°C]No infoNo Elec. Conductivity [µS/cm]No infoNo Closing pressure or static water level [bar or m] No infoAnnualy Hydrochemical analysisNo infoSporadic Scaling preventionPeriodical flushing with acidInhibitor Waste water temperature [°C]3045 Waste water treatment Seepage purifying plant - stream Mur No treatment - stream Drvanja Consession grantedYesIn process Bilaterally agreed monitoring program and passive monitoring for this aquifer not exist at present

16. ACTIONS! JOINT MANAGEMENT –Monitoring –Reporting –Permitting / protecting USE OF BEST AVAILABLE TECHNOLOGY BENCHMARKING FURTHER RESEARCH

17. Joint management Aim of monitoring is to get a representative information about the used part of the deep groundwater aquifer (M. Samek) Follow the best-practice example of the Upper Austrian – Bavarian »Malmkarst« reservoir. Level of Utilization (Exploitation) Data Acquisition (Surveys / Monitoring) Data Management 2 – Moderate utilization No interference No regional scale changes Active monitoring Operational monitoring (qualitative and quantitative) performed by users Bilateral information base Monitoring program should be agreed between users and by the bilateral commission Evaluated and calibrated bilateral numerical model for protecting and permitting basic tool should be used SI-AT ‘’Mura/Mur’’ commission opened the issue of transboundary aquifer → conclusions can be prepared

18. Using results of pilot area research: The outcome of the modeling can be used establishing the water protection area. The Bilateral database for information exchange about status and production data can be developed under patrimony of Bilateral Commission. The program of bilateral monitoring can be agreed between Slovenian – Austrian ‘’Mura/Mur commission’’ and users from both countries. Monitoring should rely on existing production boreholes, no passive monitoring is proposed. Mura/Mur commission should take the initiative!

19. Use of best available technology Any new utilisation should consider the use of dublets thus: preventing technical difficulties, minimize environmental impact, minimize impact to the aquifer, minimize the interference among users. All existent users should follow the use of doublets.

20. Benchmarking

21. Further research Improvement of knowledge about geological model (collection of new data, geophysical measurement) Implemetation of geothermal doublet (technical aspects, influence to the coupled hydravlic-temperature field Investigation of the potential in NE part of the aquifer at the border region between Slovenia and Hungary for production of electricity by binary power plants (geophysics)

22. Thank you for your attention! GBA dr. Rudolf Berka Fatime Zekiri Magdalena Bottig mag. Gregor Goetzl MFGI György Tóth dr. Gyula Maros dr. Ágnes Rotár-Szalkai dr. Teodóra Szőcs Co-workers on the Bad Radkersburg – Hodoš pilot area GeoZS Tadej Fuks dr. Mitja Janža Dejan Šram Simon Mozetič mag. Dušan Rajver Mirka Trajanova Nina Rman mag. Joerg Prestor dr. Igor Rižnar dr. Bogomir Jelen Helena Rifelj mag. Andrej Lapanje