Specific methane production activities (SMPAs) of methanogenic bacteria attached on carriers in a pilot-scale two-phase anaerobic membrane reactor were investigated. In the process a membrane was placed between acidification and methane reactors. The plant treated continuously a soybean processing wastewater. Vial tests were conducted using six different substrates and bacteria grown in each fixed bed reactor. The test results are shown as follows ;
1) Bacteria attached on the methane reactor carriers showed higher SMPAs than those of bacteria in the acidification reactor in case of using formate, acetate, propionate or butyrate as a substrate.
2) A SMPA of ethanol decomposition revealed an extremely high value concerning bacteria in the acidification reactor. It was assessed that metabolic groups of bacteria converting ethanol to methane played an important role in the acidification reactor.
3) In comparison with SMPAs of UASB granules in the literature, methane reactor bacteria had almost equal or higher SMPAs and demonstrated a similarity ot UASB granules cultured by a mixture of organic acids, Hence, the methanogenic consortia similar to those in UASB granules were estimated to be present on the carriers in the existing methane reactor.

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Sedimental denitrification activities were determined by an acetylene inhibition technique with different treatments of samples. Each method was described as follows : (I) a sediment slurry was incubated with an insitu water in a glass bottle, (II) an intact sediment core and its overlying water were incubated in a glass column, (III) emitted N₂O was collected in a glass cylinder put directly on the surface of sediment in the field.
Denitrification activities of a tidal sediment measured by the above procedures were 61-62, 33-39, 47-56 mg N·m^-2d^-1, respectively. Although the first method gave higher activity than the other two by the factor of 1.3-1.9, it has the advantage of treating multiple samples, because of needless of the complicated apparatuses for incubation. The results suggest that the simple glass bottle incubation using a sediment slurry is possibly used to asses sedimental denitrification, however, sufficient care must be taken in comparing its results the other methods.

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We conducted an investigation into the levels of organic chlorinated compounds such as Trichloroethylene (TCE) in 36 underground water wells in Kawasaki city.
A high level of TCE was detected sides of Tama river. Also, 1.1.1-Trichloroethane (MC) was detected in the Suge area. From the investigation, it was found that the concentration of MC was related to the ground water level. Therefore, we suspect that polluted matter has been buried the ground.

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A rapid and simple method for estimating BOD in waters was investigated by using a DO (Dissolved Oxygen) electrode and activated sludge acclimated to substrates. When the substrate was not added to the ML (Mixed Liquor) saturated with DO, a negative straight line for the DO decrease was obtained against the time signifying endogenous respiration of the activated sludge. On the other hand, when sodium sulfite or organic compounds was added as the substrate to the ML after a few minutes, the negative straight line with the similar slope to that obtained initially was obtained again, after a steep decrease in DO cocentration due to the biological oxidation of the substrate with the DO. The difference in DO concentration between two negative straight lines obtained before and after the addition of the substrate is directly proportional to the concentration of added substrate. This DO consumption is applied to determin the rapid BOD (BODr). The time required to measure the BODr is about 10 min. The present method was applied to the estimation of the BODr for some typical organic substrates such as ethanol, phenol, and glucose-glutamic acid with satisfactory results.

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