Sorptive solute transport through channelized flow regimes was investigated using a two-dimensional channel network model. Channel networks of various geometry were generated stochastically and sorptive as well as non-sorptive solute transports in the media were simulated. The sorption reaction was assumed to become equilibrium instantaneously and to have a linear and singular isotherm. Breakthrough curves (BTCs) in actual concentration and time were normalized by total tracer concentration and by an average discharge time of non-sorptive tracer from the network. These normalized BTCs indicate distinctive characteristics of sorptive solute transport in the heterogeneous media such that: (1)The medium with smaller average channel size gives delayed breakthrough and greater spreading in sorptive solute BTCs, whereas non-sorptive solute BTCs are not affected by average channel size, since BTCs are normalized (2) When average channel size is the same, a medium which has wider channel size variation gives significantly greater spreading in sorptive solute BTCs whereas nonsorptive solute BTCs show only slight increase in BTC spreading (3) As channel density increases, difference in effects of channel size variation on nonsorptive and sorptive solute BTCs becomes small (4) BTC characteristics are not significantly affected by channel orientation nor by variation in channel orientation, although permeability of the network is affected by the orientation of the channels. The second and the third results indicate that sorptive solute transport exhibits more pronounced effect of heterogeneity in the discrete media than nonsorptive solute transport does. It also suggests that medium with greater heterogeneity causes larger spreading in sorptive solute BTCs, which may lead to considerably early arrival of the solute to a certain point of question in a field situation.

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美濃帯に分布する三種の岩盤について.亀裂サンプリングデータとルジオン試験データを基に.亀裂特性.透水係数テンソルおよび三次元の異方性の推定が水理学的になされる.この論文では.亀裂性岩盤の水理学的な性質と亀裂系の幾何形状の統計学的な性質の両方を満足させるために.水理的等価亀裂開口幅の概念が導入されている.三種の岩盤について.実測開口幅に対する水理的等価亀裂開口幅の比が.かなり小さく求まることが分かった.このような開口幅に関する結果から.単一亀裂内でチャンネル流が起こっている可能性が論じられている.

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To construct dams on highly permeable rock foundations rationally and economically, the accurate evaluation of permeability of dam foundations is required. When we perform Lugeon water-test(LWT), the most popular in-situ permeability test for dam foundations, in highly permeable rock foundations with high injection pressure, the water flow from an injection hole becomes the turbulent flow and the flow rate is not directly proportional to the injection pressure. Therefore, equivalent Lugeon value is dependent upon the injection pressure.
On the other hand, when the water flow is laminar, the flow rate is directly proportional to the injection pressure and we have no trouble in calculating the Lugeon value. Besides, because the'hydraulic gradient of seepage in dam foundations is low and can be supposed to be almost laminar, laminar flow resistance law is necessary to estimate the amount of underseepage.
In this paper, we have developed high viscosity fluid test (HVFT) to obtain the laminar flow resistance law of highly permeable rock foundations by injecting viscous fluid instead of water.

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有機塩素化合物の除去を目的とした新しい地下水浄化用膜材料システムを提案した.このシステムは3つのユニットからなる.空気導入部および有機塩素分解部は地表に設置する.水中から有機塩素化合物を抽出するための有機塩素化合物選択透過性を持つ膜を使用したモジュールは地下水層に設置する.このシステムでは空気導入部から吹き込まれた空気が.水中から膜を透過して有機塩素化合物をストリッピングし.分解部まで運ぶ.
この論文では.数値シミュレーションを用い.このようなシステムにおける装置の影響について検討した.分析の結果.地下水浄化に必要な膜の能力およびモジュールの大きさについて大まかな知見を得た.典型的な例として.400g/dayの有機塩素化合物除去能力を持つモジュールを用いれば.1幅6mの領域を20PPmから1PPm以下に浄化することが可能である.この場合.モジュールの膜面積で1m².膜の能力としてα=10,000.flux=1009/m²hが必要となる.

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Minamiyamashiro district at Kyoto prefecture is located in the southern part of Kyoto basin. The groundwater in thisbasin has been used water service, agriculture and industry. We have study about the groundwater resources in Minamiyamashiro district, especially, we investigated agriculture, industry and water service wells respectively in 1983 and 1993 using the hearing inquiry method, and tried to grasp the pumping and the use conditions of groundwater in this area. In this paper, as compared with these data getting by the hearing inquiry in 1983 and 1993, the changing on the actual using conditions of groundwater and on the quantity of the pumping groundwater for ten years in this area are discussed. As the results, it is recognized that the total pumping quantity of the groundwater increase about 10,000,000 ton for ten years, and that the increase of pumping for water services are marked.

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