For the purpose of developing a runoff model for polycyclic aromatic hydrocarbons (PAHs) in urban areas, this study focused on the contents and profiles of PAHs in road and roof dust. The result of cluster analysis of the profiles of PAHs in the size-fractionated dust showed that roof dust formed a different cluster from road dust irrespective of either the particle size or the roof structure. Factor analysis revealed that phenanthrene, indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were important PAHs for distinguishing road dust from roof dust. The result of the factor analysis also suggested that the contribution of tires, pavements or asphalts to PAHs is greater in road dust than in roof dust and that the contribution of vehicle exhaust emission to PAHs is greater in roof dust than in road dust. A nonparametric test indicated that the contents of PAHs are higher in fine dust (smaller than 106μm) than in coarse dust (larger than 106μm).

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The dynamic characteristics of boron adsorption on saccharide-type polyallylamine resin synthesized from saccharide and polyallylamine (PAA) resin have been investigated by the column method. The column used for adsorption studies was 100mm long and 5.0mm in diameter. The saccharide-type PAA resins used as boron-adsorbent were three hexose-type PAA resins, four pentose-type PAA resins, two disaccharide-type PAA resins, and one rhamnose-type PAA resin. The breakthrough point was affected by changing the space velocity of the feed solution in the range between 5.0 and 30h^-1, and the optimum column performance was found at 5.0h^-1. The order of the adsorbed amount of boron on PAA resin modified by D(+)-mannose chemically corresponds to that of the substituted degree of D(+)-mannose on PAA resin. When a model wastewater containing 2.0mmol·l^-1 boron was passed through the saccharide-type PAA resin column at a space velocity of 5.0h^-1, the adsorbed boron amounts of 0.67mmol·ml^-1-resin, 0.61mmol·ml^-1-resin, 0.56mmol·ml^-1-resin, 0.54mmol·ml^-1-resin, 0.52mmol·ml^-1-resin and 0.45mmol·ml^-1-resin were obtained for D(-)-arabinose-type, D(+)-galactose-type, D(+)-mannose-type, D(+)-glucose-type, D(-)-ribose-type and L(+)-rhamnose-type PAA resins, respectively. When a feed real wastewater containing 24.6ppm boron was pumped into the D(-)-arabinose-type PAA resin column, the volume of effluent containing less than 0.05mmol·l^-1 boron was about 288 times as large as the bed volume of the D(-)-arabinose-type PAA resin column, which was about 3.1 times higher than that of the column of Amberlite IRA-743.

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The objective of this study is to clarify the effect of wave control by the construction of breakwater and eelgrass transplantation on eelgrass bed formation. We investigated the changes in environmental factors after the construction of the breakwater and transplanted eelgrass bed at the coast of Shimokamagari Island in the Seto Inland Sea, Japan. The rafting reproductive shoots with seeds in natural beds were predicted to be transported by the current to the transplantation area before the construction of the breakwater. However, the eelgrass bed was not formed. Wave height at the transplantation area was predicted to decrease to less than 1/5 due to the construction of the breakwater. This value was the same as those obtained for natural beds. Sediment inside the breakwater was muddier than outside and had an optimum grain size for eelgrass. Sea bottom level was stable inside the breakwater, whereas scouring that uprooted eelgrass occurred outside the breakwater in winter. The transplanted bed inside the breakwater expanded from 2,000m² to 4,200m² in two years. The moderate reduction in wave height and sediment stability caused by the construction of the breakwater played an important role in eelgrass bed formation and eelgrass transplantation.

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The purpose of this study is to clarify the feasibility of a system in which chlorophenols (CPs) are concentrated from polluted water into an organic solvent by absorbent adsorption followed by ozone decomposition of the CPs in the solvent. CPs were decomposed in organic solvents by ozone with the highest first-order degradation rate constant in acetic acid. The rate constants in acetic acid were higher than those in distilled water for 2,4,5-TCP and 2,3,4,6-TeCP however, those in acetic acid were lower than those in distilled water for p-CP and 2,4-DCP. The Freundlich adsorption constant K of CPs on granular activated carbon (GAC) were 5 - 17 times higher than those on synthetic absorbents. While the percent desorption of CPs from GAC into acetic acid was only 13 - 42%, those of CPs from synthetic absorbents were more than 94%. The concentration ratios of CPs from water to acetic acid by GAC and synthetic absorbents were 5.5×10⁶ - 5.0×10¹⁴ and 1.4×10² - 1.1×10⁶, respectively. CPs could be concentrated from water to acetic acid efficiently using absorbents followed by desorption by acetic acid and decomposition by ozone.

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Dissolved organic matter (DOM) in Lake Unmun (Korea) and its two inflowing rivers was fractionated using three resin adsorbents (XAD-8 resin, macroporous cation and anion exchange resins) into five classes : aquatic humic substances (hydrophobic acids), hydrophobic neutrals, hydrophilic acids, bases, and hydrophilic neutrals. The characteristics of DOM were investigated by evaluating DOM fraction distribution, ultraviolet ray absorbance of DOM fractions (UV absorbance at 260nm), and molecular size distribution of DOM. Aquatic humic substances (AHS) and hydrophilic acids (HiA) were found to be predominant in both lake and river waters. In particular, AHS were greater in percentage fraction than HiA. The UV to dissolved organic carbon (DOC) ratio (UV/DOC ratio) of AHS was two times higher than that of HiA. The UV/DOC ratios of the total DOM, AHS and HiA were 12.9-32.8, 7.2-29.4 and 5.3-17.1 [m ABS cm^-1·l·g C^-1], respectively. The molecular weight distribution of the lake water DOM was determined by high-pressure size exclusion chromatography and found to exhibit a relatively narrow size range and low weight-averaged molecular weights ranging from 1,010 to 1,110 g·mole^-1.

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Groundwater pollution with tetrachloroethylene (or perchloroethylene, PCE) has been found in several sites in Kanazawa City from 1982. In this study, the concentrations of PCE and its degradation products (trichloroethylene (TCE), and cis-1,2-dichlorothylene (cis-DCE) in well water samples in two contaminated areas in Kanazawa City were analyzed. One is area T located in the center of the city, and another is area I located in the southwest of the city. Groundwater was sampled at 19 existing wells at area T and at 5 existing wells at area I. Using the result of the analysis of the total molar concentration of the three compounds and the degradation ratio calculated from the molar fraction of the products (TCE+cis-DCE), contaminations were evaluated in two areas. In area T, 1) although the polluted area increased until 2000, it was decreased in 2003. This tendency was influenced by the relationship between the total concentration of VOCs and the distance from the tentative contamination source. 2) The decrease in the area polluted with PCE described above might be due to pumping of the polluted groundwater from August 2000. 3) The increase in the degradation ratio of PCE suggested that the nonaqueous PCE liquid phase had already disappeared at the contamination source. In the area I, 4) the decrease in the PCE concentration and the increase in the PCE degradation ratio suggested that the original liquid PCE did not exist at the contamination source. 5) The distribution of the degradation ratio of PCE suggested that the contamination source existed in the east-southeast direction of this group of research wells.

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