TECHNOLOGY FOCUS - BIOLOGY - Preferred Microbes: The microorganisms are microbial species which decompose non-decomposable protein, starch, etc. in excrement, microbial species with much cellulase enzyme which decomposes vegetable fiber, microbial species which fix nitrogen in air and water, and form fertilizer, hot-spring microbial species produced at 70-80 degrees C and annihilate pathogenic microbe etc., microbial species which decompose lignin of fiber, petroleum, detergent, etc., and/or marine halophilic yeast, preferably marine halophilic yeast which absorbs salt content in seawater. Bacillus excellent in deodorizing ammonia odor are adsorbed and inoculated, or fungi are utilized. According to the kind of contamination component of sewage, the microbial species are cultured for eliminating 50% or more of contaminants.    TECHNOLOGY FOCUS - ENVIRONMENT - Preferred Conditions: In the fine porous structure portion of activated coal granular, various microorganisms and fungi with water-purification capability are adsorbed and inoculated. The adsorption capacity and ion-exchange capacity resulting from the fine porous structure of activated coal granular also decompose sludge and detoxify harmful heavy metals simultaneously. An element which utilizes nitrogen and phosphorus absorbing ability from the root portion accompanying vegetation to absorb nitrogen and phosphorus is combined. The plant is directly planted in the filter medium, and is chosen from terrestrial plant having nitrogen and phosphorus absorbing ability at least 20 times compared with common aquatic plant. As water-purification facility, a plant growth field for absorbing nitrogen and phosphorus employs greenhouse structures, such as a glass house which does not easily influence the growth conditions by external temperature change. As the air-conditioner system of the water-purification facility, an energy-saving system using temperature difference with treated water and air temperature in the facility is employed. Electrical energy for facility management is provided by solar power generation device and/or wind power generator, which supplied 20% or more, preferably 50% or more. Microorganisms which decompose sludge are mixed and kept for preset time, to obtain compost by fermentation reaction, for use as soil amendment material. A nitrogen component, a phosphorus component, a potassium component, etc. are adjusted for use as fertilizer which meets legal standards. Molding is carried to a shape and volume suitable for filling a 30-50-cm-deep hole. The recycle material is used for desert greening. The material is molded into a sheet. A retention material fixable also in an inclined surface is provided. The recycle material is a greening sheet stock applicable also to an unstable inclined surface.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The heavy metals are zinc, copper, lead, cadmium, arsenic, hexavalent chromium, and/or mercury. The element which carries out ion-exchange coupling with heavy metal is carbon and/or silicon. The moisture-absorption material and water-retaining material are straw and/or water-absorptive polymer.