Recently Japanese corporations' policies for the environment have changed from a passive stance to a positive one in order to strengthen competitiveness in the market. Along with this trend, every stakeholder in the market demands that corporations tackle global environmental problems, disclose environment-related information, and show corporate social responsibility. These changes in corporate activities have produced several new types of environmental businesses. Environmental activities by not only corporations but also citizens and local governments are progressing. However, these environmental activities have some problems in developing independently and in making steady progress.
This paper reviews the current state of Japanese environmental activities by corporations, citizens and governments and considers the future of the relevant stakeholders and policies for establishing a sustainable society in Japan, that is, one in which the environment and the economy are compatible.

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Since 1986, a Hot Dry Rock (HDR) geothermal energy R&D project has been carried out at Hijiori in Yamagata Prefecture, Japan. At present, the Hijiori HDR system has two reservoirs (a shallow reservoir and a deep reservoir) and four wells (SKG-2, HDR-1, HDR-2a and HDR-3) completed in high temperature granite at the site. Injection well SKG-2 was completed in the shallow reservoir formed at a depth of about 1,800 m. Injection well HDR-1 was completed in the deep reservoir, which is located at a depth of about 2,200 m. Both reservoirs were intercepted by the production wells HDR-2a and HDR-3.
From November 27, 2000 to November 15, 2001, the Long-Term Circulation Test (LTCT), Term 1 was conducted with HDR-1 as an injection well, and HDR-2a and HDR-3 as production wells. Two important changes were noted during this test: 1) wellhead temperature at HDR-2a decreased from about 175 °C to about 110 °C ; and 2) pressure in the shallow reservoir increased toward the end of the test. These data are used to evaluate the lifetime of the deep reservoir and to assess the evolution of the multi-reservoir system during the test.
A simple multi-reservoir model was developed and the test data simulated using the FEHM (Finite Element Heat and Mass transfer) code developed at Los Alamos National Laboratory. The two most important conclusions of the modeling are: 1) the production wells produce more fluid from the shallow reservoir than from the deep reservoir; and 2) permeability of the deep reservoir increased during this test.

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This paper discusses a new method for optimization of mine ventilation system. The method is based on criteria as follows: (1) minimize the size of each regulator; (2) minimize the number of regulators; and (3) minimize the total power consumption of fans. Based on this theory, the optimization problem of the ventilation system is classified as optimization of mine ventilation network and calculation of operating points of fans. Furthermore an algorithm that determines the economical operating point of fans while calculating the optimum controls of ventilation network is proposed. The main features of this method are that it does not require the analysis of a large-scale nonlinear programming problem, and the optimal solution can be obtained by means of existing programs for mine ventilation network analysis.

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Cuttings from five excavation machines (tunnel boring machine, boomheader, rock drill, PDC rotary drill and rotary vibration drill) together with fragments produced by blasting were collected mainly in tunnel excavation sites and their particle distributions were examined.
Mean particle size of blasting was the biggest and that of tunnel boring machine the ranked second followed by those of boomheader, PDC rotary drill, rock drill and rotary vibration drill. The mean particle size of each excavation method was found to be proportional to geometric mean L of cutter spacing and penetration. It was also found that the cumulative distribution function (CDF) of particle size D reasonably well follows Rosin-Rammler distribution;
CDF = 1 - exp (-(1.87D / L)^0.88)

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In order to clarify the influence of stress rate on fatigue failure characteristics of Shirahama sandstone, loading and unloading on the rock specimens were repeated between lower (about 0.5MPa) and upper stresses under a constant stress rate. In addition, the behavior of P-wave velocity and the AE occurrence in the process of fatigue failure were investigated.
As stress rate is slower, failure at the same upper stress ratio (upper stress/compressive strength at each constant stress rate) occurs at the smaller number of the cycles. Then, the number of the cycles to failure increases exponentially as the upper stress ratio decreases.
In the fatigue process, tangent deformation modulus and lateral/axial strain ratio are significantly affected near the upper stress level by stress rate. Also, AE behavior is different with stress rate, but the effect of the stress rate doesn't appear on the behavior of P-wave velocity.
The relation between the number of cycles to failure and upper stress ratio differs in stress rate. Then, to predict rock failure in fatigue test, we should utilize the shortest elapsed time to failure estimated from the relation between upper stress and time to failure at various stress rates.

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It is prerequisite to estimate rock stress for designing underground rock structures constructed in various engineering projects such as disposal of high-level radioactive wastes. In general, rock mass is heterogeneous since it is composed of different rock bodies. Accordingly, stress measurements in a rock mass may give us only local stresses, which are affected by the heterogeneity of the rock mass, discontinuities and the surface topography of the region. Some researchers have tried to estimate regional stress from local stresses. However, the effects of the heterogeneity of rock mass have never been considered in previous studies.
In this study, regional stress in a heterogeneous rock mass was defined as an average strain field acting at boundaries, which are sufficiently far from a region under consideration. The average strain field is given by displacements as a function of the coordinates to satisfy the condition of continuity for the displacements at the boundaries. We proposed a new method for estimating regional stress from data of stresses measured in a heterogeneous rock mass by using a 3-D finite element method.
This method was applied to small-scale heterogeneous models composed of different rock bodies to know the effects of mechanical heterogeneity on estimation of stress within a region under consideration. The results showed that an estimation error increases as the heterogeneity of the rock mass increases. When the region under consideration is homogeneous, the location or number of measured points has little effects on the estimation error. On the other hand, when the region under consideration is heterogeneous, the estimation error in stress is greatly reduced by using data of stresses measured in different rock bodies. Thus, stress should be measured in different rock bodies to accurately estimate the regional stress. Finally, this method was applied to estimate regional stress in the Tono district, Gifu prefecture, but without consideration of Tsukiyoshi fault existing in this district. Although only sixteen stress components measured in three formations were used, the stress distribution estimated from the regional stress was in good agreement with the tendency of measured data.

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Effects of polymer additives such as gelatin and polyethylene glycol (PEG) on Cu electrodeposition behavior have been investigated by measuring the polarization curves for Cu deposition and the amount of additive adsorbed on Cu powder. Gelatin and PEG act as a polarizer for Cu deposition to shift the cathode potential in a less noble direction. The degree of polarization increased with an increase in the concentration and the molecular weight of additives, while the polarization effect of PEG was decreased when the molecular weight exceeded 10³. Since the amount of gelatin adsorbed on Cu powder increased with increasing the molecular weight, the polarization effect of gelatin appears to depend on its adsorptive activity on the cathode. The morphology of deposited Cu showed the compacted surface composed of fine grains with an increase in the polarization of cathode potential by the additives.

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Optical glass is the raw material for optical lens, which is used for optical equipment such as camera or facsimile. It includes a large quantity of rare earth elements for improving its optical characteristics. Therefore, because of its composition, the wastes of optical glass have a high value of resources. However, their recycling is considered to be a difficult process.
In this study, recovery of rare earth from two types of optical glass wastes (sample A and sample B) was investigated by means of alkali fusion and oxalate precipitation for sample A ,and alkali leach and solvent extraction for sample B.
Regarding to the experimental results of sample A, the grade of 83.4 % and the recovery of 71.1 % for lanthanum are achieved from waste optical glass by alkali fusion with an equivalent mixture of the fusing agent of sodium carbonate and potassium carbonate, and precipitation with ammonium oxalate.
Regarding to the experimental results of sample B, the distribution of 99.95 % La, 98.65 % Y and 95.18 % Gd from waste optical glass is achieved by alkali leaching followed by sodium hydroxide and solvent extraction with D2EHPA.

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This report presents applicability of the on-site mechanical iron-mixing treatment of contaminated soils with chlorinated organic compounds. Two types of soils contaminated with chlorinated ethane and/or ethylene were chemically treated with special iron powder E-200. The iron powder E-200 was mechanically mixed with the soils derived from the site A and B in Japan. Following to the mixing process of the soils, the treatment was carried out and controlled in piles on the ground. The soil A, contaminated with 1,1,1-trichloroethane (MCF) and 1,1-dichloroethylene (1,1-DCE), which maximum concentrations were 6.3 mg /l and 0.14 mg /l respectively, were cleaned below the Japanese Environmental Quality Standards for Soil Pollution within 5 days. During the experiment term, 1,1-dichloroethane (1,1-DCA) was detected as a main intermediate for MCF dechlorination. Small amount of the contaminants, however, dispersed from the surface of the pile, most of the contaminants reacted with the E-200 iron. The treatment for cleaning of the soil B contaminated with 0.19 mg /l of cis-1, 2-dichloroethylene (c-DCE) took 21 days, because c-DCE was regarded to be less reactive with the E-200 iron in the soil.

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Recently, several removal technologies of minor elements in copper smelting have been developed along with the degradation and the diversification of copper concentrates and also for assuring the quality of cathode. This article reviews the current and new elimination technologies of minor elements for copper smelting based on the recently published papers focusing specifically on arsenic, antimony, bismuth, lead and nickel among various impurities. In this article, the removal technologies in copper smelting are classified into five categories; (1) pre-treatment, (2) extraction from matte or copper, (3) dust treatment, (4) anode doping and (5) purification of electrolyte. Vacuum refining which is not established as a current industrial process is also described in this article.

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A large quantity of slag containing various harmful and heavy metal impurities is generated in non-ferrous metal production industry every year. In order to achieve sustainable development of the industry in Japan during the 21st century, prompt measures should be taken to deal with the ever-increasing quantities of slags. To resolve the slag issues, great efforts have been made to develop their new applications and usage. As a part of the activity of the "Committee for the Investigation Research on Development of Innovative Non-Ferrous Metals Smelting Technologies in the 21st Century", the current situation and problems on this matter are reviewed focusing on slags generated in copper, lead, zinc, and ferronickel production.

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New technologies for zinc electrowinning process were reviewed as part of the mission of the "Committee for the Surveillance Study on the Development of Innovative Non-Ferrous Metal Smelting Technologies in the 21st Century" (Alias: The Oishi Committee) at the Mining and Materials Processing Institute of Japan (MMIJ). Since more than 85% of the world's zinc is produced by means of the roast-leach-electrowin process, demand for technological innovation in zinc electrowinning continues to increase. Based on a survey of literature published mainly in the recent ten years, the committee reviewed the effect of additives and impurities, which play a very important role in zinc eletrowinning particularly at high current densities. Furthermore, some challenging technologies such as hydrogen anode and spouted bed cathode that may lead to an innovation in zinc eletrowinning technology in future, and some basic thermodynamic researches are also introduced in this article.

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New technologies for refining rare metals were reviewed as part of the mission of the "Committee for the Surveillance Study on the Development of Innovative Non-Ferrous Metal Smelting Technologies in the 21st Century" (Alias: The Oishi Committee) at the Minerals and Materials Institute of Japan(MMIJ). Since innovation in non-ferrous metal smelting technology makes a significant contribution to society, current process technologies, which have been the focus of attention in this field, were discussed by members of the committee using information from a literature survey. Based on the results of the review and discussion, current trends in the development of smelting technologies for titanium, rare earth metals, precious metals, niobium, tantalum, etc. are reviewed in this article. Technologies for smelting / refining technologies for rare metals will continue to advance in the future, especially in the field of energy-saving and environmentally sound processes, and also in the field of new electronic materials processing.

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