Upon completion, the Bátaapáti underground repository complex will provide safe storage for approximately 70000 m3 of low and medium-level radioactive waste from the Nuclear Power Generating Station of Paks.
Under a design and build contract financed by RHK Kft. (Public Limited Company for Radioactive Waste Management) Mott MacDonald has been commissioned by contractor Mecsekérc Zrt. to provide civil and tunnel engineering design services, geotechnical advice and interpretation, and specialist advice on a variety of topics such as grouting and sprayed concrete specifications and database management.
Our work on this critically important facility has been ongoing throughout the past 5 years, making us an integral part of the design and construction processes. As the engineer responsible for all mining tasks and rock support, our role has been extensive, encompassing design, consultancy and on-site supervision during construction. Through Mott MacDonald's Budapest office we were able to provide the project with the required international expertise delivered locally.
The project scope also included the creation of a Geotechnical Interpretive Report (GIR) to summarise the underground exploration findings in a user-friendly form. The findings and conclusions of the GIR, complemented by a detailed report on the emplacement caverns, were used for the design of the facility.
The designed structures include two portals; two 1750 m long inclined access tunnels; cross-passages; a transformer chamber; an explosives storage chamber; pump chambers; sumps and sump shafts; an emergency sump and the 11 m diameter emplacement caverns themselves.
Detailed design is based on the Q-system, utilising a variety of numerical modelling tools to support the empirical design. This includes modelling with FLAC 2D and 3D, UDEC, UNWEDGE and Phase2. Our internationally recognised numerical modelling skill was of paramount importance to fulfilling the client's expectations on this closely scrutinised project.
Primarily utilising a drill and blast method in a hard rock granitic formation, the total length of tunnels driven to date is over 5200 metres long, reaching to a depth of 250 metres below surface. Construction of the first two emplacement chambers including fit-out is due for completion by the end of 2012.
Botond Beno, Graduate Member, ICE Hungary Committee Member