In recent years environmental concerns about subsurface contamination has been pointed out among various fields. Dowa mining CO. Ltd., which opened up mines in the north part of Akita pref. since 1884, has been forced to turn its business field from mining to some other applications because of being weakened its competitive power of mining in the world market. One of the applications for the environmental field started up in 1987 with waste management and metal recycling using the existing facilities and skills of mineral processing and smelting in our company. Around 1990s, as our company has been recognized as providing proper management for all kinds of wastes and reducing environmental risks with highly experienced skills, social demands for treating soils contaminated with heavy metals, volatile organic compounds or petroleum hydrocarbons as wastes have strongly risen up against our company.
In order to respond to those demands, our company has introduced a new concept of "soil remediation" divide the treatment of contaminated soils from waste management. This concept was easily accepted and many kinds of the applications for the remediation were made into practice because our company has contributed to the development of subsurface materials and protection for environmental matters. Thus by applying mining facilities and skills into the new business field of soil remediation, we could accomplish the establishment of this field along with the existing technologies of mining and waste management. In our company soil remediation business can be started with subsurface investigation which is the applied technology of mine probes following to the remediation with our mining concept and technologies including incineration, bioremediation, soil washing, and chemical treatment. Based on the mining technologies described above, we could establish the overall site assessment to treat contaminated soils as “soils” properly.

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This paper is to review and summarize the past 30 years in application of automatic controls into resources processing, mainly mineral processing. The trend beyond 30 years ago was already reported on the MMIJ journals published in those days. The early seventies seem to be one of the significant milestones in the history of automatic control theory. That is to say, the so-called modern control theory had been established and became to be applied into practice.
Many plants of different industries other than mineral processing have positively adopted the highly developed deterministic control theories including the classical as well as the modern ones. Most of mineral processing plants have been rather negative in applying them. It is thought because a mineral processing plant usually involves its specific characteristics: e.g. uncertain, stochastic, nonlinear, interactive multivariable ones.
The favorable factors for automation of mineral processing can be found, however, in recent development of non-deterministic or knowledge-based, i.e. linguistic or stochastic control strategies introducing fuzzy logics, GA (Genetic Algorithm), ANN (Artificial Neural Network), expert system etc., all of which are supported by modern computer technology.
The trend mentioned above has been figured out by mentioning different examples extracted from the references, which were available for the authors, but may not necessarily be enough as a bibliography concerned.

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History of lithium batteries is briefly described with emphasis on how they have been growing, why some of them have been ruined, and which scientific field has been triggered. Some background for lithium-ion batteries is given and the state-of-art science and technology are highlighted. A series of trials on the research of lithium insertion materials for advanced lithium-ion batteries is also discussed in terms of materials science.

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Big scale construction machinery is absolutely necessary for the mineral resources development and various construction works. Troubles of the machinery give serious losses in the efficiency of operations and also in financial proceeds. In this meaning, machinery maintenance is very important for mining and construction works. Early diagnosis of the machinery is especially important to prevent a serious damage. Recently, diesel engine applied to excavation machinery are highly improved not to discharge exhaust gases of high concentration and to achieve high energy efficiency. However, a diesel engine involving non combustion cylinder has high probability to breakdown in a short time when the engine is used without any maintenance works.
In this study, autocovariance of acceleration waves of cylinder block was calculated to obtain the period of revolution, and the combustion period of each cylinder was determined. Then rms value corresponding to each combustion period was calculated. Probability of overlapped area of two curves of normal distribution, which were obtained from rms values of normal and non combustion states respectively, was calculated. It was confirmed that non combustion cylinder of a diesel engine of V-12 type could be judged clearly using the relative intensity curve of the probability. This judgement method is considered to be superior to traditional methods where more than several numbers of accelerometers were used, especially from the viewpoint of simplicity.

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The cation-exchange properties of monovalent (K⁺, NH₄⁺ and Li ⁺) and divalent(Ca²⁺, Mg²⁺, Cd²⁺, Pb²⁺ and Ni²⁺) cations has been investigated for the Na-zeolite synthesized from coal fly ash by a hydrothermal reaction. The amount of NH₄⁺ exchanged with the Na-zeolite was compared to that with a commercial product, A-4 zeolite. The effect of cations (H ⁺, K ⁺, Na ⁺ and NH₄⁺) on the removal of PO₄^3-was studied for the solution containing phosphate ions.
The cation-exchange capacity of the Na-zeolite synthesized from coal fly ash is as much as that of an A-4 zeolite. The monovalent and divalent caion exchange selectivity for Na-zeolite is shown to increase in the order of Pb²⁺ > Cd²⁺ > Ca²⁺ > K ⁺ > NH₄⁺ > Ni²⁺ > Li⁺ > Mg²⁺. It is found that the cation-exchange selectivity is closely concerned with an electric charge and a hydration ion radius of the cation. Namely, the cation having a small hydration ionic radius might exchange much more with Na-zeolite, while the cation having a large hydration ionic radius might hardly exchange.
Phosphate ions can be removed by a quantitative precipitation formation with Ca²⁺ released from Ca-zeolite. In phosphate solutions such as K₃ PO₄, Na₃ PO₄ and (NH₄)₃ PO₄, Ca²⁺ is released by an ion-exchange reaction between a cation in the solution and Ca²⁺ on the zeolite, while in H₃ PO₄ solution Ca²⁺ is supplied in the aqueous solution from the zeolite surface destroyed by the action of an acid. It is possible to remove simultaneously NH₄⁺ and PO₄^3- in (NH₄)₃ PO₄ solution through an ion-exchange reaction of NH₄⁺ with Ca-zeolite and a precipitation reaction of PO₄^3-with Ca²⁺ released from Ca-zeolite.

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Zeolite syntheses were examined using coal fly ash, paper sludge ash, municipal waste incineration fly ash, RDF fly ash and swage sludge incineration ash as raw material. The hydrothermal reaction was performed under the following conditions; NaOH concentration of 1.5 or 2.0mol/dm³, reaction time for 3 or 5h, slurry concentration of 20wt% and reaction temperature at 393K. Properties such as structure of particle surface, cation exchange capacity, chemical composition and so on were investigated for the products synthesized from various ashes. The propriety of the raw material was also evaluated. These characterized various natures including solid-liquid separation habit, which is an important factor for designing the production equipment of zeolite.
Zeolite P and hydroxysodalite could be produced from raw materials of coal fly ash and paper sludge ash in the present work. Zeolite with sufficient cation exchange capacity was synthesized from municipal waste incineration fly ash, when it was treated with water washing and acid washing in order to remove soluble or acid-soluble impurities in incineration ash. The factors affecting solid-liquid separation of zeolite owe mainly to the contents of calcium component and unburned carbon in the incineration ash. The solid-liquid separation of zeolite becomes extremely difficult when the contents of calcium component and unburned carbon exceed 30% and 10wt%, respectively. This is explaned by the phenomenon that the calcium component and unburned carbon in the incineration ashes are converted to the small floating materials with small density in alkali solution.

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In order to recover nickel ion in a spent electroless nickel-phosphorus alloy plating bath and, at the same time, to remove impurities such as iron and zinc, the applicability of solvent extraction with LIX84I as the extractant has been investigated using actual spent bath. Although the extraction efficiency of nickel from the spent bath is considerably lower than that from the nickel sulfate-nitrate solution, nickel in the spent bath is selectively extracted with high efficiency (> 99 %) at the pH of 6-7. The extracted nickel is effectively stripped by sulfuric acid at a pH of less than 3. On the basis of these results, a flowsheet for recovering nickel from the spent bath is proposed. Chemical equilibrium calculations of the spent bath have shown that the complexes of nickel with anions such as lactate and phosphonate ions become predominant in the pH range between 2 and 6. This results in the depression of nickel extraction efficiency from the spent bath as compared with that from the nickel sulfate-nitrate solution. By combining these aqueous equilibrium calculations with the extraction equilibrium and the successive aggregation equilibria of the active component of the extractant in the organic phase, the extraction behavior of nickel is quantitatively predicted.

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In Japan, surface mines mainly consist of limestone and crushed stone quarries. This paper summarizes a current situation of fatalities and injuries occurred in these surface quarries in Japan. At first, based on the annual reports of mining safety issued by MITI, severity rate (lost days per 1000 employee-hours) and frequency rate (number of incidents per million employee-hours) of limestone mines in 1954-1999 is discussed. Both rates had decreased rapidly within these years. Especially, the frequency rate has decreased logarithmically between the years of 1954 and 1990. A half-time period of the frequency rate was 7 years. Therefore, should be realized that fatalities and injuries in surface mines have been decreasing dramatically in Japan. But if we compare these numbers with other industries in Japan, the level might be regarded as not so low. For example the number of industrial accidents resulted in death was 1,884 in a calendar year of 1998. Among these, 26 people were died in surface mines. This fact resulted in higher primary rate of incidents compared with other industries.
In order to investigate these surface mine incidents in detail, a total number of 312 cases concerned about fatal and non-fatal accidents were collected from reports by LSJ (Limestone Association of Japan) and JCSA (Japan Crushed Stone Association). These incidents were grouped by place, month, day, time, age, and experience. Main results derived from this analysis are; incidents are concentrated on Mondays, and time between 9:00-10:00 / 14:00-15:00. An age group of 35-60 has more number of fatal and injury number compared to age group 18-35, and 60 over. As for experience year, almost 50 % of fatal incidents are caused by who has a mining experience less than 7 years.

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Life Cycle Assessment (LCA) has been broadly discussed, recently. However, LCA data in the mining operation, which should be the starting point of the material flow, isn't evaluated sufficiently.
The purpose of this study is to calculate and evaluate the amount of CO₂ emission due to limestone production at Japanese limestone quarries based on three kinds of statistical data, and to compare the result with other types of open pit mines. In Japanese limestone quarries, principal mining method is bench-cut in which the deposit will be sliced down from top using orepass system.
Consequently, the total amount of CO₂ emission from limestone quarries in Japan is estimated to be 428,780 t in 1998, which equals to 2.31 kg-CO₂ / t of limestone. It has been varying between 2.1 to 2.3 kg-CO₂ / t during this 15 years and tends to increase slightly after 1991. 55.9 % of CO₂ emission is caused by diesel fuel consumption, and 32.3 % by purchased electric power consumption. The most part of CO₂ emission in the mining process is originated by the diesel fuel consumption.
For the limestone quarries producing more than million tons ore per 1 year, the diesel oil consumption rate at the most fuel efficient mines was 0.25l/ t, independently of the mining scale. The amount of CO₂ emission by the haulage operation at a Chilean copper mine was found out to be nine times more than that of a limestone quarry in Japan. The bench-cut mining method has a possibility to considerably decrease the energy consumption in mining compared to other mining methods.

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Taiheiyo Cement's Garo Quarry, located in Kamiiso Town just west of Hakodate City in Hakkaido, is a historic quarry opened in 1892 to supply limestone for cement. There are no houses in the surrounding area. The closest residence is more than four kilometers away, and quarrying is carried out on a comparatively large scale under these blessed conditions. Within this enviironment, quarrying operations, carried out using the world's largest-class wheel loader and other large-scale heavy equipment, rank domestically among the top class in production efficiency. Further, careful consideration is given to protecting the surrounding environment and measures are taken to preserve the scenic view from Hakodate, a sightseeing area, and to prevent the generation of pollution from quarrying operations.
As the magnesium oxide (MgO) content varies widely in the limestone deposits distributed throughout the quarry and there are frequent intrusions of clay, quality control is extremely difficult. Given these conditions, a quality control system has been introduced and operations are carried our under very strict quality control.
In this paper, we will introduce the situation of open-pit quarrying operations at Garo Quarry.

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Modernization to blasting works has not much improved at limestone quarries in Japan, although heavy machinery and computers were introduced to mining works.
Shuhou quarry has attempted to modernize fragmentation due to blasting and improved the works, recently.
Continuous monitoring of indices, such as number of secondary blasting, amount of dozing job and loader productivity, as well as performance of trial blasting, to find effects of blasting on fragmentation was conducted.
It was found that the bottom charges using non-electric detonator and AN-FO charger for open pits made those indices more desirable. Also, the labor for charging work was reduced due to mechanization. A further improvement is planned for fragmentation control due to blasting.

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