To clarify the role of sulfate-reducing bacteria (SRB) in the Insolubilization of heavy metal ions in a waste reclamation site, distribution of SRB in leachate and reduction of heavy metal ion by SRB were studied. SRB were commonly observed in leachate. Cadmium and copper, and iron and zinc, in synthetic medium, were insolubilized within 24 hr, and 48 hr, respectively, by SRB. But reducing the ratio of hexavalent chromium reached only 16.1% after 48 hr treatment by SRB. When cadmium ion was used in the experiment, the precipitate produced was cadmium sulfide as determined by SEM and EDX analyses. These results suggest that SRB play an important role on insolubilization of heavy metals at waste disposal sites.

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Various continuous NH₃ analyzers ; catalytic conversion type, ion electrode type and UV type were compared in analysis accuracy with the indophenol method.
The catalytic conversion type NH₃ analyzer denoted slightly lower values than those by the indophenol method. The reason for the difference was estimated that the concentrations of NO, CO₂ and NH₃ in flue gas varied in shorter time than the measuring intervals of 1 s.
The ion electrode type NH₃ analyzer also denoted slightly lower values, because the flow rate of gas and absorption solution were slightly varied and the volume of the absorption solution changed with H₂O condensation from the flue gas.
The UV type NH₃ analyzer also denoted slightly lower values due to the influence of coexistent gases such as NO and SO₂.

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Bulky and uncombustible refuse discharged from households are carried to facilities for bulky refuse crushing after collection. Harmful substances are frequently present in bulky refuse and may possibly be released into the atmosphere during the crushing and compression.
To find means to prevent this, an examination was made of the emission behavior of harmful substance in exhaust gas and particulates. The results obtained indicated the following ; (1) Hg emission as gas is predominant. (2) The major source of Hg emission is crushed fluorescent tubing. (3) The greater the number of dry cells in the refuse, the higher the concentrations of Mn and Zn in exhaust particulates.

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Comprehensive index such as BOD or COD is currently used to estimate water pollution by organic substances in leachate from landfill, and any component has not been characterized in it. In order to study organic substances in pit spill from mixed refuse and in leachate from landfill for mixed refuse without incineration procedure, organic compounds have been initially examined.
As a result, amino acids and fatty acids contained in animals and plants, were detected in refuse pit spill, but not in leachate from landfill for mixed refuse. It is suggested that these are derived from the decomposition of organic components of waste inside landfill. When organic substances in leachate were analyzed by GC/MS, phthalic acid esters, DEHP and DBP, were identified in it on the basis of their mass spectra.

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