Partial analysis of flame melting technology for depths > 1000 m for underground deposition of radioactive waste

Evaluations of the analyses so far had the following results: In principle, depths below 1000 m are possible using flame melting in loose and solid rock. According to an estimate using quantitative approximation analysis, depths down to 2000 m with a maximum production cost of about 150,000 Euros/m and a resulting storage/disposal cost of about 7,000 to 10,000 Euros per m3 (including the cost of all internals and renaturation) will be economically acceptable at a maximum production cost of 200,000 Europs/m. Without the need for supports (e.g. by shortening or omitting loose rock drilling and longer distances in solid rock) and with greater depths, higher economic efficiencies will be achieved. The findings provide first recommendations concerning the diameter of underground caverns and the drilling equipment required. Criteria for a technical feasibility study are identified, and the requirements for further research and development activities are pointed out. (orig.)