A prototype probe for in-situ stress determination by borehole jack fracturing has been newly developed. The authors carried out a loading test in a steel pipe to study stress distribution on borehole surface induced by loading with the probe. Strain gages were glued on the external cylindrical surface of the steel pipe to know the actual stress distribution induced by probe loading. In order to obtain the stress distribution along the internal surface, a numerical simulation of the loading test was also carried out. Since the numerical simulation results agreed with the results measured with the strain gauges, reliability of the simulation was elucidated. Thus the stress distribution on borehole surface and a stress concentration factor at a point of fracture formation were obtained by this research. Through laboratory and field tests from now on, reliability and performance of the stress measurement using this probe will be checked.

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For the purpose of examining the adsorption behavior of fluorine on clay minerals, the adsorption equilibrium experiments on fluorine were carried out using several clay minerals. Then various analysis and considerations, as listed in the followings, were done on the basis of the experimental results.
1) The adsorbed amount of fluorine per unit mass of clay mineral was ranged as Kaolinite >Saponite >Pyrophyllite, Dickite >Montmorillonite.
2) When the mass ratio of clay mineral to liquid was constant, the ratio of adsorption equilibrium concentration of fluorine to initial one became small, as the initial concentration of fluorine was lower.
3) It was clear that there was less correlation between the BET specific surface area of the clay minerals and the adsorbed amount of fluorine, because the BET specific surface area was ranged as Saponite > Montmorillonite(Mikawa) > Kaolinite > Montmorillonite(Tsukinuno)> Dickite > Pyrophyllite.
4) The cations such as the alkali metal (Na, K), alkaline earth metal (Ca, Mg), iron, silicon and aluminum, which are contained in the clay minerals, are major chemical components which may be bonded with fluorine. However the quantitative correlation between those each content in the clay minerals and the absorbed amount fluorine could not be recognized.
5) For each clay mineral, the fluorine adsorption data can be arranged clearly in every conditions for the mass ratio of clay mineral to liquid. It was clarified the adsorption isotherm of fluorine on the clay minerals were represented using Freundlich's adsorption equation.
6) The correlation equations which took the mass ratio of clay mineral to liquid into consideration were proposed on the adsorption coefficient and index in Freundlich's adsorption equation. Using both those equations and the values of adsorption parameters obtained in this study, it becomes possible to estimate the adsorbed amount of fluorine on the clay minerals and fluorine concentration in liquid phase.

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Widely accepted concept of "sustainable development" was originated from the report, "Our Common Future", by World Commission on Environment and Development. Responding to the requirement for developing "sustainable indicators" by Agenda 21 of the World Summit in Rio de Janeiro, many organisations all over the world have been developing and proposing the sustainable development indicators for mineral industries. Transparency of the indicators is their basic common factor and it must be supported by their stakeholders.
LCA is also an accepted tool to evaluate many environmental indicators obtained through the lifecycle of products and systems. The application of LCA is expanding to social and economic fields. Methodologies for the integration of environmental impacts are actively discussed and several kinds of single index are actually adopted.
The document named "Implementation of Agenda 21" by the World Summit in Johannesburg requests lifecycle thinking for mineral industries and their commodities. There are many possibilities to apply LCA methodologies and its fundamental theories for the development of the indicators for the mineral industries. The application is supposed to bring the practical spread of them in short time among the stakeholders.

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Increased opposition from environmental groups is severely restricting the operation and planning of large-scale surface mines in the world. Some projects of surface mining will have to be cancelled and downsized due to environmental issues. Under this social situation, the mining industry has started the campaign and the public relations for the importance of extracting and using coal resources in order to mitigate the protection. It has been recognized throughout the industry that planning is essential to minimize the effects of mining on the environment. Environmental management and rehabilitation are now integral parts of planning for mining.
Mines have a finite life that ceases when the mineral has been fully extracted. During the life of mine, mining, especially surface mining, has the potential to have environmental effects that extend beyond the confines of the mine boundary. These include erosion with increases in sedimentation and turbidity in surrounding water courses and leaching of salts that also result in the reduction of water quality. These effects may range from minimal to quite severe and widespread, depending upon the physical and chemical properties of the overburden and reject materials, the climate and location of the mine, and its relationships with surrounding land uses. Rehabilitation of mines is aimed towards the projected future land-use of the area.
This paper describes surface mining systems in Australia and then discusses the factors that should be considered in order to avoid potential environmental issues resulting from surface mining when developing a new surface mine.

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India is the third largest coal producer in the world and has substantial coal reserves. It produced about 340 million tons of coal in 2002-2003. Open cast production accounts for 80% of the total output and the remaining 20% is from underground. The share of the underground output in the total production is expected to remain at the current level through 2010 even as the coal production increases. Despite its huge resource of coal, the quality of Indian coal is not so good. A considerable amount of good quality coal deposits in India lies in the thickness range of 5-12 m. However, an appropriate mining method for such thick seams could not be developed so far.
The coal's share of total electric power generation in India is 75.5% in 2001. Because it is a reliable, domestic, and low-cost source of fuel, coal has played and will continue to play a significant role in the development of the Indian economy. Production, processing, and consumption of coal, however, can have significant environmental impacts, if not properly managed.
The paper describes the present situation of the Indian coal mining industry, discusses problems in thick seam mining methods, and proposes a new mining method for thick seams considering today's environmental issues in Indian coal mining.

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The recovery of fine combustible matter from coal washery waste was investigated using a laboratory/pilot scale Mozley multi-gravity separator (MGS). The effects of parameters such as drum rotational speed, wash water rate and feed rate on the yield, the recovery of combustible matter, and the ash content of the concentrate were studied. It was found that the yield, recovery and ash content decreased with the decrease in wash water rate and with the increase in drum rotational speed and feed rate. It is estimated that these separation performances depend on the amount of particles retained inside the MGS drum. Because MGS was not suitable for the separation of very fine particles of clay minerals from coal washery waste, we suggested introducing a two-inch hydrocyclone after MGS treatment to effectively eliminate these clay minerals.
A process for the recovery of fine combustible matter from coal washery waste using four-inch and two-inch hydrocyclones and MGS was then proposed. The yield, combustible matter recovery, calorific value and ash content of concentrate obtained from the process were 37 %, 57 %, 5940 kcal/kg and 18 %, respectively. These results show the technical advantages of the proposed process to reduce waste materials and increase the recovery of salable products.

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The Japanese Ministry of Economy, Trade and Industry (METI) has undertook 5-Year project on CO₂ sequestration in coal seams since 2002. This project consists of fundamental research into CH₄-CO₂-coal interaction, CO₂ monitoring technologies, cost reduction of CO₂ capture from flue gases, and the economics of sequestration. Another component of the project is a field pilot test. After preliminary screening of potential sites, the Ishikari coalfield in Hokkaido, Japan, was selected as the pilot test site. In 2003, a well was drilled in the South Oh-Yubari district within the Ishikari coalfield, and named IW-1. This was the first well drilled in Japan from the surface to a coal seam for purposes of CO₂ sequestration and was designed for CO₂ injection. In 2004, second well (called PW-1) was drilled at the surface location 195m away from IW-1 for the production purpose. The two wells were together intended to constitute a multi-well pilot test site. A multi well CO₂ injection/CH₄ production test was conducted using both IW-1 and PW-1. This paper introduces the overall coal seam CO₂ sequestration project and presents the results of the multi well injection/production test.

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Japan's coal policy is at the crossroads; coal continues to be one of the most reliable and economically efficient energy sources and yet its preeminent position is being threatened by an increasingly acute environmental awareness. Under such circumstances, where shall we situate coal in our energy policy?
To answer these questions, "C3" or "Clean Coal Cycle Study Group", answerable to the Director of the Coal Division, issued the interim report on Japan's New Coal Policy in June 2004.
This paper describes the outline of the report and introduces the concrete measures to secure stable coal supply while tackling the global warming issues.
Below are the key points.
• It is very important to use coal to a certain extent from the perspective of diversifying energy sources. Besides, how to overcome its disadvantages and to maintain/strengthen/make the best use of its advantages is the key to position coal as more influential energy source.
• The largest disadvantage of coal, its environmental load can be overcome by clean coal technologies (CCTs). What must be achieved is, (A) the improvement on thermal efficiency through coal gasification in short-term, (B) the realization of zero-emission by CO₂ sequestration in long-term.
• For making contribution to the global environmental issues while stimulating domestic economy, it is important to balance environmental protection and economic growth by disseminating CCTs made in Japan into Asian countries on commercial basis through utilizing Kyoto mechanism.
• In order to secure stable supply at lower prices, the largest advantage of coal in mid- to long-term, where demand of coal in Asia is expected to increase from now on, it is necessary to expand the supply potential of coal-producing countries, and/or to strengthen the relationship between those countries.
• Under the recognition above-mentioned, it is vital to carry out the "C3 Initiative"

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