Opole/poland - Mar 25 2017: in the Background, in the Distance, Behind the Pool Group of People in Orange Waistcoats Listen to a Guide, an Ecologist, a Girl, a Water Specialist.the Guide Shows on the Pools For Filtration, Sedimentation of Polluted Water. Girl, Woman Talks About the Methods of Water Purification, the Norms of Water Indicators, the State of Ecology, Acidity, Water Hardness.modern Methods of Water Treatment, the Latest Technologies Are Used For Wastewater Filtration.design, Construction, Ball For Collecting Gases and Bacterial Processing. Machine Department of a Heat Station on Gas From Bacteriological Processing of a Waste. a Look From Inside to the Process of Water Purification.clean Water, Purified Water, Drain Water.protect the Resources, the Ecology of the Planet