Hiroki Ojima, Hokkaido University, Sapporo, Japan, Toru Mogi, Hokkaido Univ, Sapporo, Japan, Kazuya Ishitsuka, Hokkaido University, Division of Sutainable Resources Engineering, Sapporo, Japan, Tatsuya Kajiwara, Geothermal Engineering Co., Ltd, Iwate, Japan, Takeshi Sugimoto, Geothermal Engineering Co., Ltd., Iwate, Japan and Hiroshi Asanuma, AIST - National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan