The Japanese Government stepped up its efforts in spring 1980 to prepare Draft Environmental Impact Assessment Bill to be submitted to the National Diet for its deliberation. The Draft Bill sets out, among other things, types of projects and programmes subject to impact assessment procedure, technical guidelines based on which environmental analysis should be made, procedure to be followed, and the relationship with local ordinances. From technical point of view, however, there are a number of issues which need further study in order to ensure the effective implementation of the legislation.
These issues include precise definition of the range of actions subject to impact study, methods to predict and evaluate impacts of these actions both in terms of pollution and natural ecosystem, and principles to decide areas in and around the site for these actions where the public concerned are involved in the procedure. The range of actions subject to impact study should basically be interpreted as widely as practicable to include not only those for land development, construction work and use of facilities established, but also those to establish relating facilities such as access road and its use, with a view to enabling the result of the study to identify full range of significant impacts arising from this cluster of actions.
Issues with respect to the methods to predict and evaluate impacts on wildlife and its habitat are particularly interesting. The National Government has been conducting every five years the “Green census” on the state of the wildlife and its habitat all over the country, but further detailed information should be collected by the prefectural or municipal governments to locally supplement it. Local governments are expected to play extremely important role in the implementation of impact assessment by not only providing these detailed information on the state of the local environment but also making the project proponents known that there are strategies to conserve and manage the environment which are to be taken into account. Thus, it is expected that the environmental impact assessment can be a new and effective instrument to promote the management of the environment.

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For the purpose of looking for the catalyst for the reduction of NO by CO, CuO catalysts with the addition of rare earths were investigated.
Addition effects of rare earths were exhibited by each of Nd, Tb, Dy and Ho, respectively, improving the activity at lower temperatures about 200°C With Dy, in particular, an appreciable addition effect was found even with addition of small amounts, say 2.5%. By the addition of two kinds of rare earths a higher addition effect than single addition was obtained for (Ho+Tb) and (Ho+Nd). Catalysts consisting of (Ho+Nd)-CuO with the addition of Cr or Ba exhibited a high activity even in the presence of oxygen and water.
It is considered that the catalytic reduction of NO by CO proceeds according to a redox mechanism, the reduction process of active sites is rate controlling, and Dy added increases the rate constant of the reduction process at active sites and facilitate the activity of catalyst.
It is considered that the catalytic reduction of NO by CO proceeds according to a redox mechanism, the reduction process of active sites is rate controlling, and Dy added increases the rate constant of the reduction process at active sites and facilitate the activity of catalyst.

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Continuous air pollutants and meteorological data, which were monitored at offical stations in Kanto and Keihanshin regions from April in 1975 to March in 1977, were statistically analysed. The following conclusions were obtained.
1) The appearance frequencies of days under the closed meteorological condition were 41 and 44% of a year in Kanto and Keihanshin regions, respectively, which were both at rather higher levels by some 15% compared with the 26% of the average frequency of such days in the Kanto region for the past tan years.
2) Wind direction under closed meteorological condition in both regions showed the trend as follows:
(1) In the warm season (June to September), air pollutants were transfered to inland by a sea breeze which began to blow at about 9 a. m. and countered to seashore by a land breeze which began to blow at about 9 p.m.
(2) In the cold season (November to February), too, similar phenomena occurred, although sea and land breezes began to blow at 12 a.m. and 6 p.m. respectively.
3) SO₂ concentrations under closed meteorological condition were higher through all seasons in both regions than those under open meteorological condition.
NO₂ concentrations under closed meteorological condition were also higher through all seasons in Keihanshinregion and through autumn and winter in Kanto region than those under open meteorological conditions.
NO concentrations showed no significant difference between closed and open meteorological conditions in both regions.

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Trace odor pollutants in model garbage and a waste disposal factory were identified by gas chromatography or gas chromatograph-mass spectrometer data system. The model garbage made of foods was kept in 10 liter polyethylen bottle for 3 months at room temperature under anaerobic condition. Gas sample was collected using the cold trap method with liquid oxygen. Many of odor compounds identified in model garbage were agreed with them in waste disposal factory. About 30 substances including alcohols, esters, aliphatic hydrocarbons, terpens, fatty acids and sulfur compounds were identified in model garbage.
Aromatic hydrocarbon and halogenated hydrocarbon were additionally identified in waste disposal factory. Some compounds identified in the gases were derived from foods themselves and a part of the compounds were supposed to be due to the decomposed products containing contaminated substances. It seems probable that offensive odor of solid waste will be consisted of the mixture of a number of components.
These results would be effective to evaluate the components responsible for the offensive odor of solid waste.

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N-Nitrosodimethylamine (NDMA) has been determined for exhausts from two Japanese 2000 cc cars, equipped with three way catalyst. The exhausts were sampled by means of Constant Volume Sampler, and then passed through the collection tube packed with Tenax GC at room temperature. Collected NDMA was quantified by gas chromatograph-Thermal Energy Analyzer. NDMA 0.9-2.6 μg/Nm³ were detected under the cruising conditions of hot start 11-mode and cruising at 40 km/h on a chasis-dynamometer. Formation of NDMA as an artifact and the recovery of the collection system were also studied.

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Removal of the low molecular alcohols in the air-dilluted gaseous state by activated sludge was investigated. N-butanol (n-BA) and isopropanol (i-PA) were selected for the subjects of this investigation.
When the gaseous alcohol was individually fed into activated sludge aeration tube, each alcohol easily dissolved in the aeration tube liquor before being removed by the acclimated sludge. Accumulation of each alcohol in the aeration tube liquor was not observed. n-BA and i-PA were not also detected in the effluent gas.
Uptake rate of n-BA by the unacclimated sludge increased to 50.4 g/kg-MLSS/day after 8 hours. On the other hand, that of i-PA gradually enhanced and were 24, 38 and 57 g/kg-MLSSiday at the 1st, 2nd and 3rd day, respectively. Such uptake rate were dependent on the sludge concentration. The maximum uptake rate were 130 g/kg-MLSS/day for n-BA and 94 g/kg-MLSS/day for i-PA.
Treating the mixed gas containing n-BA and i-PA, it obtained the same results on the removal efficiency and the acclimation time in comparison with that of single alcohol.
When i-PA-containing gas was continuously fed without addition of other nutrients during 30 days, removal rate of i-PA was about 99.5% through this experiment period. Foaming and the sludge defrocing occurred after 7th day.

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An attempt is made to obtain a relationship between the annual mean concentration of an air pollutant and the: probability with which the annual quantile or the maximum value exceeds a given environmental standard of the pollutant.
Since the distribution of air pollutant concentration is often represented by a log-normal distribution, the asymptotic distributions of the sample quantile and extreme value in the case of a log-normal distribution are proposed.
These results are applied to determine the design annual mean concentration of NO₂ or SO₂ with a fixed calculated risk which is the probability of the annual quantile or the maximum value to exceed the standard level.

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