The study to predict effluent quality indicated by TRS (transparency), SS, TOD and TOC from sewage treatment plant carried out using the improved Group Method of Data Handling (GMDH) reported by IHARA. Generally, absolute mean value of error was used as criterion function for selection in the GMDH.
In this paper, relative error is used as a criterion function for selection, because the data of effluent quality from sewage treatment plant does not show normal distribution in some cases, and also, correlation coefficient is used as the function in order to take similality of the variation patterns of the predicted values and of the measured values more important than closeness of the two.
Three kinds of GMDH-programings are studied by comparison. The results were evaluated by prediction errors and comparison of the predicted values with the measured values in graphs, and the following were cleared. 1) The difference in the prediction errors of the three kinds of GMDH-programings was a little. 2) The prominant difference by the methods appeared in the case of TRS. The R. filter GMDH (correlation coefficient was used as a criterion function for selection.) was the best among the three in fitting with the predicted values for large variation of the measured values.

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As one of the studies on the aspect of water pollution of the Lake Kasumigaura, the second largest lake in Japan, the accumulation and the distribution of the fission products, in the lake, which were originated from the past nuclear tests were investigated.
The Sr-90 concentrations in the lake are 0.8 pCi/l in water, 230 pCi/kg in the dried sediments, 5-100 pCi/kg in living fish and shellfish. The concentrations of Cs-137 are 0.2 pCi/l in water, 2 × 10³ pCi/kg in the dried sediments and 10-60 pCi/kg in living fish or shellfish. The areal distribution of Sr-90 in sediments is uniform all over the Lake. However, Cs-137 concentration in the bottom sediments of the near shore is lower than that in the center of Lake. The vertical distribution of both nuclides in the sediments of the central bottom are shown as follows.
(1) Sr-90 concentrations in the layer from 0 to 30 cm in depth and Cs-137 concentrations from 0 to 20 cm are higher. The concentrations of both nuclides are highest in the range of 10 to 15 cm.
(2) Sr-90 concentrations in the layer between 30 and 45 cm in depth and Cs-137 concentrations between 20 and 25 cm are intermediate.
(3) Sr-90 concentrations in the layer deeper than 45 cm and Cs-137 deeper than 25 cm are very low.

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This study discussed on the analytical method of nonionic surfactants by cobalt thiocyanate method coupled with ion exchange.
Cobalt thiocyanate method was improved in points of sensitivity and spctra in UV region by modifying salt and extractive solvent with KCl and 1, 2-dichloroethane. Nonionic surfactants of different ethyleneglycol content varied the sensitivity of this method, but generally used nonionic surfactants, which were composed of ethyleneglycol between several and some thirty, were similar in sensitivity.
Other surfactants such as anionic, cationic and amphoretic, and stearate as a sort of soap interfered this method positively. Chemical sizes, high molecular coagulants and protein interfered negatively, but amines, iron and abundant alcohol, positively.
Nonionic surfactants except amines were separated from anionic and cationic surfactants by double ion exchange column : Dowex AG 50W ×4 and Dowex AG 1 ×4, 8 cm height-2 cm dia. ; with 250 ml of (1+1) aqueous ethanol, 24 ml/min. The recovery, reproducibility and the result of standard addition method to the liquid-waste of dye works by overall procedure were very satisfactory. Applicated this procedure to the crude and treated liquid-waste of dye works, operation was facilitated with regard to emulsifying and colouring, and analytical data were 050% less than that without ion exchange.
1090 mg/l of nonionic surfactant was contained in the liquid-waste of dye works and 2 mg/l, in urban river water. The nonionic surfactants detected in these samples were several times more than anionic surfactants.

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By carring out acid-hydrolysis, photo-oxidation and autoclave wet-oxidation for sea water, it became possible to determine some chemical forms of dissolved phosphate to some extent; the concentrations of organic monophosphate and dissolved total phosphate were determined by photo-oxidation and autoclave wet-oxidation, respectively. By combining photo-oxidation with autoclave wet-oxidation, the concentration of dissolved polyphosphate was determined. In addition of acid-hydrolysis to these reactions, it was found that the concentrations of organic and inorganic polyphosphate could be separately evaluated. The above technique was applied to natural sea water and river water near Hiroshima city, and the chemical forms of phosphate measured in these waters were discussed. The determination of the chemical forms of dissolved phosphate is considered to give an important clue for the elucidation of dynamic aspect of phytoplankton in coastal marine.

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The basic organic compouds in the marine sediment of industrial area were analyzed to research organic compounds in aqueous environment. The sediments were extracted with benzene by using a continuous extractor for 12 hr. Hydrochloric acid solution (1N) was added to the benzene extracts, and the mixture was shaken for 5 min. The acid layer separated from the benzene layer was made alkaline by the addition of sodium hydroxide. The alkaline aqueous solution was extracted with diethyl ether. Then the ether extracts were dehydrated with anhydrous sodium sulfate and were concentrated with a Kuderna Danish evaporator. The concentrates were separated and analyzed by gas chromatographic mass spectrometry and its high resolution mass spectrometry. By this method many nitrogen-containing polycyclic aromatic hydrocarbons such as quinoline, acridine, aza-fluorene, and their. N-oxides were found.

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