1. Thermodynamic Reference Database Helge C. Moog Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) Helmholtz-Zentrum Dresden-Rossendorf, Institut für Radiochemie (HZDR-IRC) AF Consult (Switzerland) Karlsruhe Institute of Technology, Institut für Nukleare Entsorgung (KIT-INE) TU Bergakademie Freiberg, Institut für Anorganische Chemie

2. Basic idea Thermodynamic calculations of various institutions become compareable, by creating parameter files from a common database. 2 PHREEQC Reference database GWBEQ3/6CHEMAPP

3. Common database manipulation tool DB-Control Webbrowser

4. Screenshot of DB-Control  Addition and modification of phases, phase constituents, data etc.  Operated with a normal web browser  Extensive control and edit functions  Allows de-centralized operation of a single database

5. Long-term useability  Useage of open-source programs  Low degree of abstraction of the data model  Documention of databank structure  Flexible databank structure  Joint project of five research institutions

6. Data structure: Phases and Phase constituents 6 aq UO2 2+ Phase Constituent Phase U 4+ UO 2 (OH) + Elements 1 U, 2O, -2 EA1 U, -4 EA1 U, 3 O, 1 H, -1 EA

7. Data structure: Phase constituent types and Reactions 7 UO 2 2+ Secondary Master Primary Master U 4+ Products UF 2 2+ ReactantCoefficient UF2 +1 U F -2

8. Internal calculation scheme  A technical framework which ensures that dependent and independent data are stored in a manner which ensures internal consistency when independent data are modified  Editor determines, which data have to be calculated and how  Internally, calculations are executed by SQL scripts  Only those data are recalculated which are affected by a change

9. Benefit of THEREDA  The scientist can focus on scientific issues.  Peripheral programs assist in debugging, surveying, converting, and exporting data into ready-to-use parameter files.

10. Benchmark calculations 10  To be performed with parameter files created from the databank  Demonstrate that calculational results match with lab data or expert judgment  Make sure that results are the same with several codes (or give reasons why they cannot because of shortcomings of the code)  At any new release: repeat earlier benchmarks and make sure that the results still agree with earlier ones  Is a means of control for the user to check the accurateness of the downloaded parameter file

11. Criteria for releases 11  Completeness of data for the systems considered  Completeness of data assessment  Check of parameter files  Benchmark calculation: Equivalent results with all codes considered  Completed documentation of benchmark calculation

12. Benchmark calculations released so far 12  R01: Polythermal solubilities in selected ternary solutions with regard to the system of oceanic salts  R02:  Am(III), Cm(III), Nd(III) in MgCl2 and CaCl 2 solutions at 298.15K  Am(III), Cm(III), Nd(III) in NaCl solutions at 298.15K  R03: Solubility in selected ternary salt solutions with regard to the system of oceanic salts in presence of CO2 and carbonates  R04: Solubility and hydrolysis of Np(V) in NaCl solutions at 298.15K  R05: Activities and solubilities in solutions of Cs, Na, K, Mg, Ca, Cl and SO4 at 298.15 K These parameterfiles are ready for download to anyone interested!

13. Benchmark calculations in preparation 13  Solubilities and activities in solutions of metastable and stable cement phase assemblages  (Am, Cm, Nd) – (SO4, CO3) – H2O  Na, K – PO4 – Cl, SO4 – H2O  Th(IV), Np(IV) and Pu(IV) solubility in NaCl, CaCl2, Na2CO3 and KHCO3 solutions  U(+IV/+VI) solubility in NaCl solutions  Generally: solubilities of Si/Al-bearing phases at elevated temperatures  Fe(II) – Na, K, Mg, Ca – Cl – H2O for 25°C

14. Using THEREDA (1) 14  Select Single Data Query >> get equilibrium constants, Pitzer parameters  Export as CSV or MS Excel © possible  Select Tailored databases >> get parameter files for  PHREEQC  EQ36  GWB  CHEMAPP  Please visit: www.thereda.de

15. Using THEREDA (2) 15  Export data in a generic, computer-readable format: JSON This format can be downloaded for everyone interested to feed other geochemical codes!

16. Current activities / Outlook  THEREDA has been extended to hold surface complexation data. Further activities will include the implementation in DB-Control.  Implementation of a model for non-ideal gases: Spycher-Reed.  Extension of some data-sets to higher temperatures  Possibly addition of another supported code Ich würde hier auf jeden Fall noch expliziter erwähnen, (1) dass THEREDA sehr an Kontakt mit anderen Projekten, die auf ähnlichen Thematiken arbeiten interessiert ist. Insbesondere LANL-CO und SNL sind konkret anwesend. Auch PSI. (2) Bereitschaft von Seiten THEREDA, definitiv von KIT-INE, zu vertiefter Kooperation zur Data-selection bzw. Comparison of Models. (long-term option: joint work on specific open questions. Aufgrund multioptionaler Struktur von THEREDA ist Möglichkeit, weitere Ausgabeformate zu bedienen. (3) Einerseits Gelegenheit zu a) bilateralen Interactionen der jeweiligen beteiligten Institutionen. Siehe Tabelle am Anfang mit den Partnern von THEREDA und deren Zuständigkeiten. b) Zweiten wäre von THEREDA die Möglichkeit gegeben, dass jemand als sog. Associated Group, bei jährlichen Treffen anwesend ist.

17. Possibilities of cooperation with THEREDA  We are open for and very much interested in cooperation with other institutions related to  Database creation and management  Data selection and –evaluation  Comparison of models for specific systems  Implementation of more export formats for other codes  Bilateral cooperations with a member of THEREDA on specific issues  Usage of THEREDA as technical platform for the creation of other databases not consistent with the Pitzer model  Application of our data to own systems of interest; feedback by dropping a post in our forum or by using bilateral connections with one of the THEREDA- members  Annual informal meetings to streamline common efforts on building a thermodynamic database

18. Conclusion  THEREDA offers a web-based, state-of-the-art thermodynamic reference database for high-saline aqueous systems in equilibrium with nuclear or non- nuclear waste forms in Germany  Joint-project of five research institutions  Access to code-specific parameter files  Means of directing future research and of quality assurance for gouvernment agencies, service provider, and research institutions  Future extensions of the thermodynamic database for nuclear and non- nuclear waste forms in Germany in conjunction with THEREDA

19. THEREDA is jointly funded by the Federal Ministry of Education and Research (BMBF), the Federal Ministry of Economics and Technology (BMWi), and the Federal Office for Radiation Protection (BfS) with funds from the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU). Acknowledgements Special thanks are extended to all members of the THEREDA team, for dedication, perseverance, and for the readiness to collaboratively work for a common goal.

20. Thank you very much for your attention!