Sensitivity analysis for a high-level radioactive waste repository with the bounding fracture-transport model

19A 911142 Evaluation of predictive models of temperature distribution in geological disposal of high-level waste: influence of thermal conductivity of formation Palancar, M C; Aragon, J M; Luis, P; Diez, M Radioact Waste Manage V14, N3, 1990, P207-219 A previously developed theoretical model for temperature distribution in a formation containing a cylindrical heat source of decaying power was evaluated experimentally at laboratory scale, using an electric heater in a compacted common salt mass. The model was inaccurate if thermal conductivity is considered constant, but acceptable match is found between theory and experiment if a temperature dependent conductivity is incorporated. 911143 Sensitivity analysis for a high-level radioactive waste repository with the bounding fracture-transport model Ahn, J; Suzuki, A Radioact Waste Manage VI4, N4, 1990, P257-273 Deterministic estimation of risk is complicated by scenario uncertainty and parameter uncertainty. Sensitivity analysis is carried out to investigate effects of variation of fracture width (fractal distribution),matrix diffusion coefficient (lognormal distribution), and time (Ioguniform distribution) on the bounding model for nuclide transport through a fractured medium. Large width fractures are of primary importance at small times. Effects of narrower fractures and other variables become more important at longer times, and may be negligible for shorter life nuclides. 911144 State-of-development in measurement of soil suction Fredlund, D G; Rahardjo, H Proc International Conference on Engineering Problems of Regional Soils, Beijing, 11-15 August 1988 P.582-588. Publ Beijing: International Academic Publishers, 1989 Measurement of soil suction is essential to application of unsaturated soil mechanics to engineering practice. The theory and definitions of total, matric and osmotic suction are first briefly presented. Methods of in situ measurement of soil suction and their instrumentation are described and discussed: tensiometer, thermal conductivity sensor, psychrometer, filter paper, and pore fluid squeezing methods. 911145 Modelling waste emplacement and the physical changes to the sediment barrier Freeman, T J; Hollister, C D Proc Conference on Disposal of Radioactive Waste in Seabed Sediments, Oxford, 20-21 September 1988 P199-219. Publ London: Graham and Trotman, 1989 (Advances in Underwater Technology, Ocean Science and Offshore Engineering, V I 8 ) Emplacement of radioactive waste in the seabed and its interaction with surrounding sediments will induce changes in these sediments. Results of mathematical and physical modelling and field tests for drilled and projectile emplacement are presented and discussed. Limiting projectile penetration depths are adequate and penetration paths are vertical. Holes behind the projectile will close. Upward advection of pore water in the sea bed is very slow, even when heating effects are taken into account. Faults in abyssal plain sediments, thermally induced near-field fractures,and their potential as preferential migration paths are assessed.

911146 Modelling of the coupled beat flow and consolidation around hot cylinders buried in clay Savvidou, C Proc Conference on Disposal of Radioactive Waste in Seabed Sediments, Oxford, 20-21 September 1988 P221-236. Publ London; Graham and Trotman, 1989 ( Adrances in Underwater Technology. Ocean Science and Offshore Engineering, 1/18) Heat transfer in saturated clay around a container of heat generating radioactive waste has been modelled mathematically using closed form solutions of Booker and Savvidou (1983) and Savvidou (1984), and using the finite element code HOT CRISP (Britto, 1984). Laboratory tests at lg and centrifuge tests at 100g using kaolin clay surrounding a heat source were also carried out. Temperature and pore pressure responses are compared and discussed. Results indicate the most critical stage for damage to the sediment barrier is during and immediately after projectile emplacement.

Permeability and capillarity See also: 911383, 911449, 911450, 911451 911147 Minipermeameter-based study of permeability trends in channel sand bodies Dreyer, T; Scheie, A; Walderhaug, O Bull Am Soc Petrol Geol V74, N4, April 1990, P359-374 Large scale sexiimentological units with specific ranges of hydraulic properties are ideal building blocks in modelling petroleum reservoirs. Minipermeameter measurements made on outcrops of channel sands are presented and quantified in terms of grain size, grain sorting, mineralogy, fabric and cementation. Discrete groups with characteristic permeabilities were found, and their lateral and vertical extent investigated. The detailed patterns built up can be used as input in scaling up procedures for reservoir simulation and to study flow properties of channel sand bodies. 911148 Sand-bentonite linen field control methods Chapuis, R P Can Geotech J 1/27, N2, April 1990, 1'216-223 Soil-bentonite liners at waste disposal sites are controlled in situ either directly, by control of compaction and mixture, or indirectly, by local permeability tests or global leakage measurement. Thermal dilation of infiltrometers is shown to affect accuracy of in situ local tests. An analysis of total leakage is presented which allows detection of hydraulically induced damage or deterioration. Coupled hydrometer tests or X-ray analysis are suggested for checking local bentonite content meets design specifications. 911149 Hydraulic characteristics of four pentlnnds in Minnesota Gafni, A; Brooks, K N Can J Soil Sci V70, N2, May 1990, P239-253 Hydraulic gradients and groundwater velocities were measured for one mined and three unmined peatlands. Velocities were measured at shallow depth using the point dilution method. Hydraulic conductivities at different depths were estimated from field measurements using Darcy's Law. Hydraulic gradient was persistent through summer and generally less than I%. Maximum groundwater velocity of 0.49 cm/h was found in upper, least decomposed layers. Velocity decreased

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