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Water pollution | Stronger efforts needed by EPA to control toxic water pollution | Toxic water pollution
1991
Pollution prevention | Meeting the environmental challenges of the 1990s
1991
[Forest decline and air pollution. Results of five years of research (1985-1990) in the framework of the French program DEFORPA [forest decline attributed to air pollution]]
1991
Landmann, G. (Institut National de la Recherche Agronomique, Seichamps (France). Centre de Nancy, Station de Recherches Sol Microbiologie et Nutrition des Arbres Forestiers, Programme DEFORPA)
Soil vapor extraction technology
1991
Pedersen, Tom A. | Curtis, James T.
Chemical reactions of metals with humic material
1991
Livens, F.R. (Institute of Terrestrial Ecology, Merlewood Research Station, Grange-over-Sands, Cumbria LA11 6JU (UK))
Dying forest and air pollution: what we have learnt (DEFORPA program 1984-1991)
1991
Landmann, G. (Ministere de l'Agriculture, Paris (France). Departement de la Sante des Foret)
Prosperity without pollution
1991
Hirschhorn, Joel S. | Oldenburg, Kirsten U.
Protective measures of water resources in the Federal Republic of Germany
1991
Lersner, H.L.F. von (Federal Environmental Agency, Berlin (Germany))
Impact of liquid wastes on surface and groundwater resources and their elimination through proper treatment and reuse
1991
Hartmann, L. (Karlsruhe Univ., Karlsruhe (Germany). Institute for Bioengineering and Technology of Wastewater)
A short historical review shows that treatment plants have been developed only after problems have occurred. The high diversity pollutants of totally different origins and natures, and chemical and biological characteristics require different tools. A good approach is to select one basic tool and try to integrate tools for other tasks within this main tool. The main tool will be in almost every case (for municipal wastewaters) an activated sludge plant surrounded by other elements of polishing or for the elimination of nitrogen, phosphorus, etc., according to the local situation. Some tasks like elimination of pathogens or eggs of intestinal worms, are automatically performed to a high degree in connection with the task of eliminating degradable organics. Special wastewaters with certain pollutants have to be treated at the place of their origins. For wastewater of agricultural production direct or indirect recycling should be favoured. For wastewater of industrial background containing toxicants, treatment must be economically included in the production process of the main product. Besides this, there appears a multitude of organics of unknown chemical composition and environmental significance. They should be permitted for public application only after lab tests have proved their degradability and the conditions of their degradation. Finally, one should always be aware that treatment plants have to be composed according to local conditions. Depending on the amount and composition of wastes, an integration of tool has to be found that not only meets the demands stemming from the wastewaters but also can be integrated into the existing economical and ecological frame
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