The pollution of surface/ground water caused by the inflow of acid water including heavy metals poses serious environmental problems around the mine areas and excavation sites. The acid water is generated by decomposition of sulfide minerals such as pyrite. Because the Hakkouda Tunnel in northeast Japan passes near the mine area, it is feared that water pollution around this tunnel occur due to the acid water drainage from rock muck disposal site. Therefore, at excavation of this tunnel, the rock muck was disposed after evaluation of acid water drainage ability. We assessed the evaluation method of the ability of acid water drainage of rock muck from the results of long-term leaching test of rock samples and the leachate water quality monitoring at rock muck disposal sites.
From water qualities of leachates drained from disposal sites, we contend that the evaluation method could discriminate the rock muck that have high probability of acid water drainage from the others rock muck. S/Ca mole ratio was most effective to judgment in acid water drainage ability of mudstone. In the case of volcanic and pyroclastic rock, most contributory item was sulfur content in rock.
The leachate water from the controlled rock muck disposal site did not become acid, and heavy metal content of the leachate water was lower than the standard of discharged water. Therefore, it seems that the evaluation method of rock muck overestimated the ability of acid water drainage. However we consider that the method was reasonable in consideration of recent social situation for the environment around the civil working site.
Based on the results in the Hakkouda Tunnel, we suggest the examination for evaluation of ability of acid water drainage from rock muck on the civil working around the mine areas as follows. First, the distribution area and/or length of rocks with high-risk of acid water drainage and the volume of controlled rock muck must be estimated correctly by the horizontal drilling examination in advance. Next, at the excavation, the geology of cutting face must be checked and the water quality of leachate water from rock muck disposal site must be monitored. It is effective that the rock muck having high risk of acid water drainage is disposed in the controlled disposal site similar to the industrial waste disposal facility. However, it is necessary to examine the structure of disposal site that have high economical efficiency and same effectiveness concerning acid water drainage controlling.

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Acid rain and nitrogen-based fertilizers are the main contributors to soil environmental pollution in many parts of the world. According to the Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), approximately 44.3 to 44.6 tgN/yr of nitrogen oxides are added to the troposphere by fossil fuel emissions. These additions can lead to acid rain. Another environmental problem is the contamination of the soil by the addition of excess nitrogenbased fertilizer. The ultimate result of acid rain and excess N-fertilizer use is acidification of soil water leading to serious problems of eluviation of aluminum and clay or dissolution of harmful heavy metals. The volcanic ash soils in Japan are known as being resistant to acidification. However it is not clear how volcanic ash soils are affected by acid rain and fertilizer.
This study examines the response of Kanto loam to pollution of subsurface layers by nitrate. Chemical properties of Kanto loam soil samples were assessed by exchangeable acidity and soil column tests. The pH and pK of samples were determined by exchangeable acidity tests using distilled water and potassium chloride solution. The saturation column test was conducted to obtain a break-through curve and to calculate the dispersion coefficients by the one dimensional convective-dispersion equation. The CDE helps our understanding of the underlying mechanisms of subsurface solute movement. The extent of nitrate transfer was confirmed by percolation of 0.15mmol nitric acid through columns packed with 25g of the soil sample and 2, 800g of silicate sand.
The shift in exchange capacity was due to a change in the allophane and halloysite contents of the clay mineral fraction. The pH change from 5 to 7 over the full duration of the experiment. The study revealed the following: 1) It is considered that the buffering capacity is derived from the clay minerals in the loam. 2) However, some parts of the shallow layer have a tendency to decrease in buffering capacity. 3) The Kanto loam at the investigated site was assumed to either be susceptible to a collapse of clay or to consist of a less stable form of allophane.
The environmental pollution of the subsurface layer of this Kanto loam was thus attributed to excess nitrate in the soil water. If an acidic pollutant was introduced into this Kanto loam, the soil would be seriously damaged.

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This paper presents the excavated muck identification method used for the Yukisawa Daini Tunnel, applying threshold of 1) pH attained through batch leaching test, 2) ignition loss, 3) bulk rock sulfur contents and 4) Sulfur/Calcium molar ratio. It also introduces deposal method of excavated muck.
The section between Ohdate and Kosaka interchanges of the Nihonkai-Engan Tohoku Expressway in Akita Prefecture is currently under construction. Through the initial survey of Yukisawa Daini Tunnel, leached selenium was detected from the excavation site, and exceeded the limit regulated under the Soil Contamination Countermeasures Law. As the conventional identification method for the excavated muck contamination requires much time, faster simplified method should be identified.

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Although mines occasionally cause environmental pollution, their location and the geological characteristics provide information useful for risk assessment on environmental pollution caused by rocks.
In this study, in order to predict the heavy metals contamination on construction sites caused by natural rocks, the distribution map and the database of mines all over Japan have been constructed with special emphasis on the identification of places of high risk.

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The waste caused by the disaster (Disaster Waste), its amount is large, and its kind is various. Then the disaster waste is exhausted in a short time. Thus, it is not treatable in a usual social system. Moreover, there is the waste left for the long term. In this paper, we examine the groundwater and land pollution caused by the disaster waste.
1) In the temporary depository of the disaster waste, there is a possibility that the organic decay under the reluctance environment is occurred. At this time, it is a possibility of the deterioration of situation caused by adding the deodorant medicine. Therefore, for the disaster waste which is various and not classified, it is necessary of early processing and disposal.
2) In the temporary depository, the elution of harmful heavy metal would be occurred, thus there is a possibility that these metals are concentrated to the groundwater and soil. Therefore, we need to execute the appropriate groundwater/soil contamination countermeasures.
3) The disaster waste left at a long term would be a source of combined pollution with heavy metals and oil compounds, etc. And, the fire/harmful gas caused by decay would generate at the deposit area of disaster waste. Therefore, we must grasp the situation change and quantity of these left wastes, and examine the countermeasure.
4) For disaster waste left at a long term, the high density dioxin would be contained in the residue and the incineration ash such as the burning houses. We need to also examine the problem of the dioxin of disaster waste.

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