A parallel waterway test was conducted to verify the ability of zeolite rocks, shell-bearing clastic rocks and woody biomass chips containing ferment bacilli to remove T-N, PO₄-P and other physicochemical pollutants from water. Zeolite rocks from Tan-no Town in northeastern Hokkaido consist predominantly of heulandite-clinoptilolite series minerals and lesser quartz, plagioclase and opal-CT. The cation-exchange capacities (C.E.C.s) of zeolite rocks ranged from 170-176 meq/100g. Commonly occurring shell-bearing clastic rocks from Akan Town in eastern Hokkaido are dominantly calcite with lesser quartz, plagioclase, smectite, heulandite-clinoptilolite series minerals, gypsum and pyrite. The C.E.C. of shellbearing clastic rocks was 39 meq/100g.
The results of this parallel waterway test clearly demonstrated that the zeolite rocks, shell-bearing clastic rocks and woody biomass chips were effective for removing of PO₄-P, NH₄-N, NO₂-N, NO₃-N, T-N, COD and BOD from the river water.

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Porphyry-style gold deposits, defined primarily by large-scale tonnage (50Mt-1000Mt) and low-grade (0.5-2g/t:Au), are represented by more elevated gold contents when compared with porphyry-style copper deposits. In addition to their significant economic contribution, an extensive zonation pattern in alteration and mineralization in porphyry-style gold deposits have become important research objectives serving as clues to trace the genetic linkage of magmatic intrusions and their associated hydrothermal systems, incorporating the porphyry-style copper deposits and epithermal ore environments. Based on reviews of the latest better-documented research with particular emphasis on morphology and fluid evolution in porphyry-style gold deposits in the Maricunga belt of Chile and other porphyry-style deposits, the controlling factors for gold and copper contents in porphyry-style deposits are examined. Assuming mineralized fluids separated from the same initial composition of magmatic intrusions, Cu/Au ratio of porphyry-style deposits is considered to be controlled first by depth, where intrusion emplaced while accompanying fluid immiscibility, and second, by the highest temperature of immiscibility for mineralized fluid derived from magmatic intrusion. But it also depends on the evolution of hydrothermal system involving boiling and/or flashing events. A recommended threshold pressure (ca. 0.5 kb) and temperature (ca. 500°C) will lead to the mineralized boiling fluid dividing into porphyry gold deposits at lower pressure and higher temperature and porphyry copper deposits at higher pressure and lower temperature. This index may provide an exploration tool for identifying the Cu/Au ratio of porphyry-style deposits.

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The present study examines the migration behavior of minor and rare earth elements(REEs) in acidic soils such as andosol, loam and red-yellow soil. Al normalized values calculated from analytical results clearly indicate that the mobility of Ca, Mg, Sr and REEs in loam and red-yellow soil is smaller than that in andosol. The difference in the mobility of these elements is considered to have been caused by the different soil constituent minerals. Especially, the mobility of the REEs depend greatly on the type of clay mineral in soil. In the red-yellow soil containing illite, smectite and vermiculite, the lower mobility of light REEs compared with heavy REEs is controlled by the adsorption by these secondary minerals. On the other hand, in the andosol containing allophone, the higher mobility of the light REEs is controlled by the adsorption by allophane. This may be related to different hydrated ionic radii of each REE.

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A “Fossil hydrothermal system” that appears now on the surface by erosion gives useful information about the underground hydrothermal fluid flow around the volcanoes. Near the boundary between the Saga and Nagasaki prefectures, late Pliocene volcanism composed of rhyolite, dacite, andesite and basalt occurred extensively, and they are accompanied with hydrothermal alteration. The Arita-Ureshino hydrothermally altered area is distributed concordantly around faults with a direction of NW-SE to NNW-SSE.
Volcanism in this area started at about 2.7Ma as basalt at Koshidake, and rhyolite erupted about 2.7 to 2.4Ma in the Arita district. Afterwards Kokuzo andesite, Imari andesite and Kobodake andesite erupted almost simultaneously during 2.4 to 2.2Ma, and finally Hasami rhyolite(2.2Ma), Kawatana-Sasebo rhyolite(2.1 to 2.0Ma) and Ureshino ryholite(1.9Ma) erupted. It is considered that the Pliocene volcanism continued without long intervals and was caused by magmatism related to each other based on the K/Ar ages and continuous bulk composition of the volcanic rocks. Hydrothermal alteration moved from the Arita and Kinzandake districts(about 2.2Ma) to the northern Kurokamiyama and Ryumon and southern Furukoba districts (2.0 to 1.8Ma) based on K/Ar ages of sericite. This possibly shows that heat sources of the hydrothermal systems were different between northern and southern parts of. the Arita-Kinzandake district.
The oxygen isotope ratio of sericite in the hydrothermally altered rocks show a minimum of 2.7‰ for Kodaru in the Hasami district and a maximum of 9.5‰ for Izumiyama in the Arita district. It is thought the lower oxygen isotope values for the Hasami district indicate a higher temperature and more active hydrothermal activity than other districts including Arita. This is concordant with the distribution of temperatures estimated by fluid inclusions in quartz veins in this area.
A low gravity area around Omura Bay is interpreted to be caused by a half-graben structure accompanied with deep fractures. A hydrothermal solution rose at the eastern margin of the graben in the NNW-SSE direction, which caused an active hydrothermal system in the Arita to Ureshino area. The gravity anomaly suggests a similar structure with deep fractures in Takeo area. The deep fractures associated with the graben structure are assumed to control the formation and distribution of not only the Pliocene fossil hydrothermal system but also the present hydrothermal system, Ureshino and Takeo hot springs. In north Kyushu during the Tertiary, a graben structure accompanied with many NW-SE to NNW-SSE normal faults formed the sedimentary basins. Therefore, in the southwest back-arc side, it is considered that some old deep fracture structures in north Kyushu provided the place for the development of a Pliocene magma-hydrothermal system.

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Manganese-oxidizing microorganisms are distributed in a wide range of environments. Amorphous biogenic manganese oxides play a significant role in the control of trace phase distribution in aquatic system. Some of them, which are tolerant to extremely high concentrations of Mn and have optimum pH less than 7, can be practically applied to treatment high Mn water, such as Mn-rich mine drainage. Additionally, the biogenic Mn deposits are poorly crystalline and significantly porous, providing highly efficient reaction fields in the environments, which are approached for decomposition and molecular size reduction of organic compounds like humic substances, oxidants, adsorbents of toxic metals, and so on.

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Temporal changes of the leachate quality have been considered as useful indicators for clarifying the stabilization of landfills. In this study, the sorts of inorganic ions and the temporal changes of the ionic concentrations in the leachate were aimed to estimate the stage of the stabilization. 6 controlled landfill sites and an inert type landfill site were used for the examination. Furthermore, the effectiveness of resistivity monitoring was examined to compensate the insufficiency with the current method for estimating the stabilization.
The main results of this study are:
(1)The main inorganic ions in the leachate are Na⁺, K⁺, Ca₂₊, Cl^-and HCO₃-.
(2)The ionic concentrations in the leachate increase for the beginning period of the filling, and shift to decrease during or after the filling. Namely, most of the soluble components with wastes have been leached by the permeable water. In gen-eral, AL₂O₃, SiO₂ and CaO contents increase comparatively in the wastes after leaching,
(3)The temporal changes of the resistivity of landfills are good indicators for clarifying changes of these conditions.

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