Déchet dangereux | EPFL Graph Search

thumb|Panneau à l'entrée d'une décharge de déchets dangereux (États-Unis, 1972). Les déchets dangereux sont une des catégories de déchets définies par la législation propre à chaque pays, qui s'oppose à la catégorie des déchets non dangereux. Ils se caractérisent par leur dangerosité pour l'environnement ou la santé à travers leurs effets directs ou indirects à court, moyen ou long terme. Pour cette raison, ils doivent être collectés, transportés et traités de manière appropriée, et plusieurs stratégies d'États, de collectivités (dont l'Union européenne) ou d'entreprises visent à réduire leur production. Les déchets dangereux peuvent être apportés à des déchèteries communautaires spéciales. Les déchets dangereux peuvent être éliminés par incinération ou par enfouissement dans des décharges spéciales, appelées en France (ISDD). Ils doivent être prioritairement valorisés. Définition et caractérisation Définition Dans l'Union européenne, notamment en France conf

Méthode de détection et de caractérisation de pollutions du sous-sol par les sites contaminés à l'aide des traces inorganiques

Contaminated sites form one of the major causes of environmental pollutions, in particular those of the soil and of the underground. One of the main problems presented by these sites is their location. Since water is the main contamination support in soil and underground, it is necessary to get good indicators to be able to detect pollution sources in areas where suspected sites location remains unknown. This is also necessary for the monitoring of contaminated sites in time and space. The aim of this project is to enhance the use of inorganic trace elements by offering specialists a new investigation tool adapted to a survey strategy of contaminated sites in various geological conditions like those found in Switzerland. This study has shown, through numerous site descriptions (41 sites) and the statistical approach of collected samples (222 samples), that the use of inorganic trace elements is helpful for the survey of contaminated sites. The most interesting result shows specific indicators for hazardous waste. Principal results Some inorganic trace elements represent almost exclusively hazardous wastes, since they are missing in the domestic and in the inert wastes. We also showed that these trace elements are typical indicators allowing to detect the presence of hazardous waste mixed with domestic wastes. These elements are : Se, As, W, Cs, Sc, Bi, Ga, Hg, Ag. Domestic and inert wastes do not show any characteristical trace elements. In general one can find the following elements in more or less important amounts in domestic wastes : Cu, U, La, B, Al, Ni, Co and Zn, Li in inert wastes. We also noticed that main inorganic trace elements in landfill leachates are : B, Ba and Br, of which the concentration is often close to or greater than mg/l. Tritium is also often associated to landfills. The comparison between uninfluenced groundwater collected during this study and polluted groundwater has allowed to value some inorganic trace elements. These elements differ significantly from the natural background when polluted sites are encountered. We distinguished specific indicators that are not present in uninfluenced groundwater : Cs, Sb, Sn, Ag, Bi, La, Se and tritium. We also put forward the presence of typical tracers showing anomalous concentrations in case of pollution by landfills, such as : Ti, Co, V, Ni, Cu, Ba, Br and B. Guide values could be established for these elements for their use in detecting contaminated sites. The same process was adopted for a limited amount of samples in surface waters. The significant trace elements are the same as for groundwater, except Sn and La. Hg, Cd and Pb which, on the other hand, could be detected at significant concentrations in cases of pollutions by contaminated sites.

EPFL1997

Using very toxic or especially hazardous chemical substances in a research and teaching institution

Sebastian Brückner, Jean-Luc Marendaz, Thierry Meyer

Wrong manipulation, storage or disposal of chemicals can cause great damage whether it occurs on industrial plants, in academia or at home. Amongst the numerous reasons, lack of knowledge and haste are the most common ones. Except for a few substances subject to international agreements, the academic world benefits from a great latitude in the use of chemicals. To make colleagues aware of the hazards and risks associated to chemicals, and protect them accordingly, the Occupational Safety and Health service of the School of Basic Sciences (SB-SST) has decided to submit to authorization the purchase and manipulation of very hazardous chemicals. The process starts by a thoughtful discussion with the requester about the substance and whether a less hazardous alternative could be used instead. If the request is validated, the work procedure is analyzed and the protective measures for safe manipulation of the chemical checked. Consequently the SB-SST authorizes or not the personnel to order the compound. This innovative participative risk-management concept is illustrated herein with osmium tetroxide, as an example of a lethal compound used in chemistry, biology and electronic microscopy. The data resulting from the authorization process is recorded in a database and the need to review the associated procedure and/or the authorization itself is performed twice a year during safety audits of the workplaces.

2016

Méthode de détection et de caractérisation de pollutions du sous-sol par les sites contaminés à l'aide des traces inorganiques

EPFL1997