HR: 1340h
AN: H33D-1611    [Abstracts]
TI: In-situ Hydraulic Property Estimation With Minimum Chemical/Microbiological Disturbance for HC Modeling of Sedimentary Rocks
AU: * Ito, K
EM: kazumasa-ito@aist.go.jp
AU: Suzuki, Y
EM: yohey-suzuki@aist.go.jp
AU: Suko, T
EM: sukou-takeshi@aist.go.jp
AU: Seki, Y
EM: yoji-seki@aist.go.jp
AU: Takeno, N
EM: n.takeno@aist.go.jp
AB: For the investigations with drill holes aiming at a modeling of groundwater flow and mass transport with chemical and microbiological interactions, the minimization of chemical disturbance caused by drilling and in-situ hydraulic test is necessary for the long-term monitoring of groundwater chemistry and microbiological conditions. The authors carried out 350m drilling with ultra-filtered and deoxygenated drilling water in stable sedimentary rock area, and applied fluid electric conductivity (FEC) logging, flowmeter logging to estimate hydraulic properties along the borehole. For the continuous monitoring, the multi-packer type pressure measuring and sampling system was installed to monitor hydraulic pressure and chemical/microbiological environments. By using the transient pressure change at the water sampling as a small pressure pulse, hydraulic properties of sampling intervals were estimated with numerical inversion. Chemical analyses of groundwater samples showed the discontinuous profile split by tuff layer in massive mudstone. From the results of FEC logging, the authors calculated relative transmissivities and hydraulic heads of representative inflow/outflow points, and these values showed good accordance with flowmeter logging and multi-packer pressure measurements. With the hydraulic property and hydraulic head profile obtained in these measurements, groundwater flow model that gave a reasonable accounts to the chemical profile could be constructed.
DE: 1829 Groundwater hydrology
DE: 1832 Groundwater transport
DE: 1835 Hydrogeophysics
DE: 1846 Model calibration (3333)
DE: 1849 Numerical approximations and analysis
SC: Hydrology [H]
MN: 2007 Fall Meeting