ICONE23-1637 DOPAS EPSP EXPERIMENT

Abstract

Within DOPAS project (Demonstration of Plugs and Seals), which involves the participation of 14 European organizations an Experimental Pressure and Sealing Plug (EPSP) is being constructed and tested by a Czech consortium made up of SURAO, CVUT and UJV Rez, a.s. at Josef underground laboratory. The aim of the experiment is to develop and demonstrate the feasibility of such plug for deep geological repository of radioactive waste in real conditions. In order to achieve this not only EPSP plug is constructed but extensive monitoring programme is carried out too. The EPSP experiment is located inside experimental gallery niche. The niche was reshaped in advance and surrounding rock has been improved by grouting. The EPSP itself consists of pressurization chamber (connected via boreholes to technology), inside plug made of low pH glass fiber shotcrete, bentonite sealing section, filter and outside concrete plug. A water, air and bentonite suspension is planned to be used as pressurization media. Possible flow through the inside plug should be stopped by bentonite sealing section. Filter at the end sealing is for monitoring of possible leakages. As part of the demonstration the bentonite emplacement technologies such as shot clay are being tested.