Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Onoe, Hironori; Kimura, Hitoshi*
JAEA-Research 2019-001, 57 Pages, 2019/08
JAEA-Research-2019-001.pdf:10.03MB
In this study, predictive simulations were conducted in order to understand recovery behavior of groundwater environment during groundwater filling test and underground facility closure. As a result of predictive simulations of groundwater filling test, difference of groundwater environment changes around the closure test drift according to groundwater filling volume was confirmed quantitatively. As a result of the simulations, groundwater environment changes at 10 years after underground facility closure could be estimated. And, it was shown that up-corning of deep saline water through drift and shaft was occurred if hydraulic conductivity of backfill material is higher than host rock.
Iwatsuki, Teruki; Onoe, Hironori; Ishibashi, Masayuki; Ozaki, Yusuke; Wang, Y.*; Hadgu, T.*; Jove-Colon, C. F.*; Kalinina, E.*; Hokr, M.*; Balv
n, A.*; et al.
JAEA-Research 2018-018, 140 Pages, 2019/03
JAEA-Research-2018-018.pdf:40.68MB
DECOVALEX-2019 Task C aims to develop modelling and prediction methods using numerical simulation based on the water-filling experiment to examine the post drift-closure environment recovery processes. In this intermediate report, the results of Step 1 (Modelling and prediction of environmental disturbance by CTD excavation) are summarized from each of the research teams (JAEA, Sandia National Laboratories, Technical University of Liberec). Groundwater inflow rates to the tunnel during the excavation, hydraulic drawdown, and variation of chlorine concentration at monitoring boreholes in the vicinity of the tunnel were chosen as comparison metrics for Step1 by mutual agreement amongst the research teams. It is likely to be possible to foresee the scales of inflow rate and hydraulic drawdown based on a data from the pilot borehole by current simulation techniques.
Hosoya, Shinichi*; Yamashita, Tadashi*; Iwatsuki, Teruki; Saegusa, Hiromitsu; Onoe, Hironori; Ishibashi, Masayuki
JAEA-Technology 2015-027, 128 Pages, 2016/01
JAEA-Technology-2015-027.pdf:33.66MB
The study for development of drift backfilling technologies is one of the critical issues in the Mizunami Underground Research Laboratory (MIU) project, and its purposes are to develop closure methodology and technology, and long-term monitoring technology, and to evaluate resilience of geological environment. To achieve the purposes, previous information from the case example of underground facility constructed in crystalline rock in Europe has been collected. In particular, the boundary conditions for the closure, geological characteristics, technical specifications, and method of monitoring have been focused. The information on the international project regarding drift closure test and development of monitoring technologies has also been collected. In addition, interviews were conducted to specialists who have experiences involving planning, construction management, monitoring, and safety assessment for the closure. Based on the collected information, concept and point of attention, which are regarding drift closure testing, and planning, execution management and monitoring on the closure of MIU, have been specified.
Sugita, Yutaka; Kanno, Takeshi; Ishikawa, Hirohisa; Ishiguro, Katsuhiko
PNC TN8410 96-014, 46 Pages, 1995/12
None
Iwatsuki, Teruki; Hayashida, Kazuki; Murakami, Hiroaki; Watanabe, Yusuke
no journal, ,
Geochemical condition and solutes transport property in and around a simulated closure tunnel were studied by observing the behavior of REEs at Mizunami Underground Research Laboratory. Results show that the REEs in the closure tunnel tend to be immobilized by absorbing to shotcrete and the colloidal flocculation.
Iwatsuki, Teruki; Murakami, Hiroaki; Watanabe, Yusuke; Fukuda, Kenji
no journal, ,
Drift closure test was carried out to understand the hydrochemical influence of cement materials to groundwater in Mizunami Underground Research Laboratory. In the end, the amount of cement material including portlandite to evolve the alkaline groundwater was quantitatively estimated 0.5mm depth of shotcrete.
Iwatsuki, Teruki; Murakami, Hiroaki; Watanabe, Yusuke; Fukuda, Kenji
no journal, ,
We considered the evaluation method of chemical influence of cement material on groundwater when closing tunnel. As a result, it is considered that long-term pH condition around the tunnel can be estimated by thermodynamic analysis of the groundwater flow, the applied cement material, accompanying water chemistry and the amount of alkaline groundwater.