After the 1970s, harmful substances that had derived from industrial activities and had been released into the environment in the past were found to be the main sources of soil and groundwater contamination. Many environmental damages such as pollution caused by heavy metals and volatile organic compounds have been reported. Against this situation, the Ministry of Environment (Environment Agency until 2001) established the "Environmental Quality Standards" for soil in 1991, "Survey and Countermeasure Guidelines for Soil and Groundwater Contamination" in 1999. Finally, "Contaminated Soil Countermeasure Law" was formed on May 29, 2002, and enforced on February 15, 2003.
In this low, several philosophies had changed from conventional thinking in the former guideline. For example, responsibilities of pollutant and land holder become clear, contaminated lands can be utilized under control and so on.
In this paper, soil remediation technologies were reviewed in addition to the explanation of the new law.

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鉱物資源の評価予測において，多金属鉱床の評価のために提案された富化比(ER) と鉱石価値(OV) から貴重な示唆が得られる。例えば，世界の鉱床は，鉱種には関係なく，高富化比―高鉱石価値(HH : 0.7%) 高富化比―高鉱石価値，(HM : 0.7%)，高富化比―低鉱石価値(HL : 0%)，中富化比―中鉱石価値(MH : 0.6%) 中富化比―中鉱石価値(MM : 51%)，中富化比―低鉱石価値(ML : 13%)，低富化比―高鉱石価値(LH : 0.02%)，低富化比―中鉱石価値(LM : 17%)，低富化比―低鉱石価値(LL : 17%) の9の範疇に分類できる。これらの範疇は，それぞれいくつかのキーワードで特徴づけられる。すなわち，HH は不整合とミシシッピー渓谷，HM は鉱脈，ML は砂岩，ストックワーク，鉱染，LMは正マグマ成，ラテライト，コマチアイト，化学的，LLは斑岩，鉱染，砂鉱床で特徴づけられる。一方，MM はいかなるキーワードによっても特徴づけられない。それぞれの鉱床の鉱種を富化比と鉱石価値で定義すると，金とニッケルはほぼ同じになるが，銅，銀，亜鉛は多少異なり，モリブデンと鉛は大いに異なる。定義により鉱種が異なるグループのうち，鉛と亜鉛は補完的である。すなわち，もしPb + Znという鉱種を定義すると，鉛あるいは亜鉛に分類される鉱床はいずれの定義にもとづいてもPb + Znと分類される。黒鉱型の亜鉛，浅熱水成銀，塊状硫化物型亜鉛，火山成亜鉛は一般的に副産物金属を伴うのに対し，正マグマ成クロム，化学的沈殿銅，砂岩型ウランは副産物金属をほとんど伴わない。

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Uniaxial compression test, Brazilian test and fracture toughness test were carried out for Inada granite and Shirahama sandstone in pure water controlling the water temperature between 0 °C and 80 °C and the loading rate between 1.67 × 10^-7 m / s and 5.00 × 10^-4 m / s. The uniaxial compressive strength, Poisson's ratio, Indirect tensile strength and stress intensity factor decreased with the temperature for the both two rocks. This tendency was clearer for Inada granite. Critical compressive strain value (axial strain value at peak load point) of Shirahama sandstone also decreased with temperature. However, the effect of temperature on the critical extensile strain (radial strain at peak load point) was not clear for the both two rocks. Young's modulus seemed to take the peak value at 20 °C or 40 °C. These results were explained based on thermal stress due to anisotropy and difference of thermal expansion coefficient between the mineral grains, stress corrosion and change in viscosity of water.

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Geothermal gradient of Toyoha Mine, which produces Lead-Zinc ore minerals with some silver content, is 20-30 degrees centigrade per 100 meters, and highest rock temperature reaches more than 150 degrees centigrade in the working area. In this situation, countermeasure for hot conditions should be required seriously. In addition to the big diameter long hole drilling for the return air shaft and the cool water spray at the face, thermal environmental analysis has been applied. This paper summarizes the results of thermal characteristics of the mine and some examples of application to the field by thermal environmental analysis.
Large scale ventilation network with 304 nodes, 484 roads and 6 fans has been constructed and thermal environmental analysis of the full mine basis has been conducted to match the original state of the mine, and short, middle and long term thermal environment estimation analysis has been conducted. But big differences of the calorific values, which are added in the underground, has been shown between simulations and measured data.
In order to grade up the accuracy of the analysis, the estimation of individual thermal origin has studied, i.e. heat from blasted ore and rock, blasting, diesel and electric equipment, and so on. And thermal environmental analyses of the partial basis including heading block and extraction block have been done to set the thermal characteristics. Also suitable heat transmission compensation factor, surface area compensation factor, and others have been considered by case studies.
Using the studied results noted above, authors applied this technology to actual field, such as ventilation plan at headings by sensitivity analysis, assessment of thermal condition improvement by some kinds of backfilling at post-extraction block, and support the underground layout design. Finally, it is proved that thermal environmental analysis technology is able to contribute the improvement of safety, productivity, and energy cost saving.

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The mechanical properties and electrolytic behavior of Pb-Ag-Ca alloy in the sulfuric acid electrolyte for insoluble electrode of zinc electrowinning were studied. Furthermore, experimental research on the influence of rolling and annealing treatments on these properties of Pb-Ag-Ca alloy was carried out. The results are summarized as follows.
The tensile strength and yield strength of both as-cast and annealed Pb-0.5%Ag-(0.05 ∼ 1.0 %) Ca-alloys were the same or higher in comparison with the conventional Pb-1%Ag alloy. The tensile strength and yield strength of rolled Pb-0.5%Ag-0.6%Ca alloys shows a constant value after annealing at 200 °C for 48 hours. The Vickers hardness of Pb-0.5%Ag-Ca alloys shows a constant value after annealing at 200 °C for 48 hours. The Pb-0.5%Ag-Ca alloy shows the same or better mechanical properties relative to the conventional Pb-1%Ag alloy.
The bath voltage of the Pb-0.5%Ag-0.6%Ca anode for the 20-day electrolysis experiments in the sulfuric acid solution decreased compared with the Pb-1%Ag anode, and the difference between the bath voltage corresponding to the Pb-1%Ag anode and the Pb-0.5%Ag-0.6%Ca anodes increased with increasing annealing time. The β-PbO₂ diffraction peaks were detected by the X-ray diffraction patterns of Pb-0.5%Ag-0.6%Ca anodes after 20-day electrolysis and these peaks become sharper with increasing annealing time. It was considered that the β-PbO₂ was one of factors contributing to the decrease of the bath voltage.

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A new approach for the synthesis of spinel-type ferrites under hydrothermal conditions has been investigated using the Schikorr reaction method. Magnetite was synthesized using ferrous sulfate solution containing small amounts of metal ions, including Ni²⁺, Co²⁺, Cu²⁺ and Pd²⁺ ions, respectively. Other workers have achieved the synthesis of magnetite above 160 °C by the Schikorr reaction, but the present work shows addition of Ni²⁺ ions is the most influential factor effecting acceleration of the reaction. In this study, low temperature (at 110 °C) magnetite synthesis was achieved by addition of Ni²⁺ (Ni / Fe = 0.34 mol%). Ni²⁺ is likely to be reduced by H₂ generated during the Schikorr reaction, with the newly formed Ni metal providing the catalyst to accelerate the dehydrogenation reaction. The most effective reaction mechanism for synthesis of magnetite above 150 °C is the Schikorr reaction, although other magnetite formation mechanisms may be effective at reaction temperatures less than 150 °C. During the Schikorr reaction, Fe²⁺ in solution is oxidized to Fe³⁺ accompanying the oxidation of Fe²⁺ to Fe³⁺ due to reduction of SOM₄^2-.

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The exposure rates, the distribution of exposure paths and the risk level of inorganic arsenic containing in soil and groundwater in Japan have been evaluated by using originally developed risk assessment model.
Major exposure path for human to arsenic in Japan was food intake. The average total exposure rate was estimated about 4×10^-1 to 5×10^-1 (95% confidence interval (CI)), which revealed that the skin cancer risk resulting from oral intake was about 6×10^-4 to 7×10^-4 (95%CI) and the lung cancer risk resulting from inhalation intake was about 2×10^-4 to 2×10^-3 (95%CI). The total exposure rates from soil and groundwater paths were about 3×10^-3 to 5×10^-2 (95%CI), which revealed that the average oral and inhalation cancer risk (95%CI) was evaluated at 4×10a^-6 to 8×10^-5 and 1×10^-5 to 2×10^-4, respectively.
The contaminated area where soil concentration was higher than Japanese criteria of total content in soil (150mg/kg) had the oral cancer risk more than 5×10^-4 to 1×10^-3 (95%CI) and the inhalation cancer risk 2×10^-3. The risk level of contaminated area exceeded groundwater criteria (10μg/l ) was estimated at about 3×10^-5 to 8×10^-5 (95%CI).

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Applicability of flow pump permeability tests to estimate storage coefficients was studied. We used an analytical solution including the effects of the storage capacity of the flow pump apparatus, and calculated sensitivities of storage coefficient and storage capacity of the flow pump apparatus on the solution. Our results suggest that the ratio of the storage capacity of the apparatus to that of the sample (δ' = C_e / S_sAL) should be less than 0.3 to obtain the storage coefficient with sufficient accuracy. The storage coefficients obtained from flow pump permeability tests are consistent with those from poroelastic parameters when δ' is less than 0.7, supporting the results of our theoretical analysis.

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Oscillation method is one of the most instructive methods to evaluate lower permeability and storage capacity coincidently. Constant sinusoidal pore pressure changes at upstream side of the specimen give rise to a response of sinusoidal pressure changes at downstream reservoir with amplitude attenuation and phase retardation. By measuring the attenuation and the retardation, the permeability and the storage capacity can be calculated. If the specimen has lower permeability, the pressure of downstream reservoir responds smaller amplitude and larger retardation against pressure wave at upstream reservoir. The usual graphical analysis estimates how the range of the attenuation and the retardation measured can produce most accurate values of permeability and storage capacity respectively. The most accurate value of the permeability can be required at 0.08 of attenuation and -87° of retardation, and that of the storage capacity is at 0.12 of attenuation and -117° of retardation. However, the graphical analysis is inefficient because of requires lot of data set of permeability and storage capacity. Then, we developed a calculation program to increase the calculation efficiency by using the iterated Newton method.
As examples, we investigate the permeability and the storage capacity changes while a fault in sandstone entrained low-permeable siltstone along sandstone surface during the sliding. To obtain the amplitude and the phase of both pressure waves of upstream and downstream reservoirs, Fourier transform was adopted. This Fourier analysis occurs periodic errors with twice frequency of the oscillation test on the data of the amplitude attenuation and the phase retardation. These periodic errors on the attenuation and the retardation induced more 2 orders of magnitude variations on the result of storage capacity when the attenuation and the retardation are lower. With these reductions, the variation of storage capacity becomes less than one order of magnitude. On the other hand, the permeability resulted from the oscillation method is independent on the pressure conditions and the accuracy is higher than that of the storage capacity.

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The storage capacity of the flow pump experimental system influences the transient response of pore pressure, and hence affect the evaluated values of storage coefficient of test specimens from experiments. To test the effect of the storage capacity of experimental system, sandstones and granites were tested by flow pump methods. The storage coefficients of sandstone obtained from the flow pump tests were very close to those from the poroelastic parameters, however the obtained storage coefficients of granites samples were not consistent between the two methods. We consider the difference to be caused by the ratio of the storage capacity of the system to that of the specimen, and this ratio should be less than 0.3 to obtain the storage coefficient with sufficient accuracy.

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This report presents a newly developed gas-medium tri-axial testing system capable of performing permeability test of rocks at effective pressures to 180 MPa, corresponding to the depth of about 10 km. Two permeability testing methods using the system, the oscillating pore pressure method and the gas flow method, were described for the case of using nitrogen gas as a pore fluid. The oscillating pore pressure method has been used to test permeability of the Kakegawa Group siltstone. The test results are summarized as : (1) Permeability of the Kakegawa Group siltstone generally decreased gradually with increasing effective pressure ; (2) In most cases the decreased permeability during the pressure increased period were not recovered to the initial value with depressurization ; (3) Each trend of the permeability reduction against the effective pressure change was almost similar to each other, while the overall permeability level of the each curve was different ; (4) Difference of the initial porosity of the specimen seemed to be responsible for the observed difference of the overall permeability level, and (5) Permeability of the sample became to be almost independent to the initial porosity at higher effective pressure more than about 100 MPa.

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