This is a biological decontamination method. Okumura Corporation possesses oil-degrading microbes isolated from nature and has great advantages in purification of oil-contaminated soil. Culturing microbes which have a strong purification capability and applying them into contaminated soil is called bioaugmentation and this efficiently decomposes contaminants.
Bioremediation has little negative influence on the surrounding environment as it does not use strong chemicals like oxidants. It also decreases CO2 emissions as it does not use heavy machines like excavators. It, therefore, is an ideal purification method compatible with SDGs (Sustainable Development Goals).

A Closed System Disposal Site (CS Disposal Site) is a safe final waste disposal landfill facility with a lid and impermeable wall/floor isolating contaminated soil from the natural environment. As CS Disposal Site is not affected by rain or snow, and the amount of leachate can be controlled by scheduled watering. While effective watering is conducted to encourage the stability of landfilled waste, leachate is recycled through a water treatment facility to prevent the contamination of the external environment. It is also possible to collect leachate components and use them, thus contributing to resource recycling.

The greening of rooftop controls the heat-island phenomenon of cities and provides a peaceful and comfortable space for city life. The rise in temperature is prevented by the blocking of sunlight and transpiration of plants, which not only reduce the air conditioning load of buildings, but also provide plentitude for inorganic building space and allow people to enjoy their contact with nature