堆積岩地域の水理特性を把握するためのモデル解析

Numerical Simulation in Order to Identify Hydrological Properties of Sedimentary Rock

野本 康介*; 松井 幹雄*; 井上 博之*; 吉野 尚人; 唐崎 建二*; 伊藤 一誠*

Nomoto, Kosuke*; Matsui, Mikio*; Inoue, Hiroyuki*; Yoshino, Naoto; Karasaki, Kenji*; Ito, Kazumasa*

高レベル放射性廃棄物の地層処分サイトの安全評価では,調査結果に基づいてサイトの地質学的,水理学的,化学的特性などを理解する必要がある。調査結果は,地下水流動および物質移行モデルの構築,モデル解析のためのパラメータ設定に適宜反映される。堆積岩地域の水理特性把握を目的として,サイクル機構の深地層の研究施設計画のうち,幌延地域で認められている地下水中の塩水や溶存ガス,地層中での高い間隙水圧などの特徴を考慮した解析を実施し,地下水流動や物質移行に及ぼす影響について検討を行った。

In the safety assessment at geological disposal of High Level Nuclear Waste, it is necessary to understand several properties like hydrological, geological and chemical properties of the disposal site by site investigations. The investigation results should project to the ground water flow modeling, migration modeling and the parameter assignment of these models. Japan Nuclear cycle Development Institute is going to carry out two Underground Research Laboratory plans in order to push on with the project and help to make up the safety criteria of the geological disposal. Horonobe is one area of these plans. In Horonobe, following properties were identified./-There are saline and fresh water./-There is dissolved gas in the underground water./-The underground of some area has high water pressure./In this study, the analysis considering above properties were carried out for understanding of hydrological properties in sedimentary rock. In addition, the affection to the water flow and migration influenced by the results were examined.