Recently, bioremediation has been attracting much attention for purifying water bottom sediment. So far, this method has been applied only to relatively small areas such as ponds or fish breeding facilities and its application to a wide sea bottom area has seldom been reported. Economical way to distribute tablets or particles containing bacteria uniformly to the seabed on the wide range application is not clear.
　This paper proposes a new method to scatter the sea bottom sediment clarification materials and evaluates its applicability and efficiency.
　The key point of the method is a blower on a ship that sprays the particles into the air. This method ensures the wide spread of particles and the uniform settlement on the seabed.
　In this study, the following observation or measurements were carried out:
1) Behavior of the particles when scattered into the air.
2) Diffusion of the particles in water.
3) Detachment of the bacteria from the particle in the scattering process.
　Based on the test results, a design of the new method was proposed and its efficiency, economy and accuracy were estimated. It was found that the new method has efficiency about 120 times as much and costs about 1/30 compared to the usual diver-oriented seeding. Particle dispersion is about 20% by the standard deviation. With regard to detachment of bacteria from the particles in the seeding process, a certain decrease in number was observed, but the degree was not crucial, nor affects the purification function of the material.