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Chalhoub M.,Bureau de Recherches Geologiques et Minieres | Amalric L.,Bureau de Recherches Geologiques et Minieres | Touze S.,Bureau de Recherches Geologiques et Minieres | Galle P.,Bureau de Recherches Geologiques et Minieres | And 4 more authors.
Journal of Soils and Sediments | Year: 2013

Purpose: Remobilization of polychlorobiphenyl (PCB)-contaminated sediments by anthropogenic activities (e.g. dredging) or natural flow conditions could lead to the release of PCBs into the water column and consequently increase the availability of PCBs to benthic organisms. The fate of the released PCBs following such events is not well understood and such knowledge is necessary for the management of contaminated sediments. The objective of this study was to understand the processes that control the fate of PCBs following remobilization of field-aged contaminated sediments. Materials and methods: Sediments contaminated with PCBs collected from Lake Bourget (Savoie, France) were resuspended in a column experiment. The relationships between physical-chemical parameters-i.e. suspended particulate matter, pH, inorganic and organic carbon content, redox-sensitive species and the concentrations of dissolved PCBs both in the water column and in the interstitial water of the sediment-were investigated so as to determine the key processes controlling PCB fate. Results and discussion: Following the simulated resuspension event (SRE), dissolved PCBs were found in much higher concentrations in the water column than under stationary conditions. Desorption of PCBs from the sediment depended on the degree of the hydrophobicity of the PCBs and the initial PCB content in the sediment. Principal component analysis showed that the variations in the concentrations of released PCBs over time and space closely followed those of suspended particulate matter (SPM) and not those of redox conditions. The partitioning behaviour of PCBs on SPM showed that equilibrium state was not attained within 40 days following the SRE. A particle size fractionation study, before and after remobilization of the sediment, showed the presence of PCBs in every fraction of the sediment, but with higher amounts in large particles with high organic matter content and in the finest fractions. Remobilization of contaminated sediment did not affect this distribution profoundly but a significant enrichment in PCBs of the clay-sized fraction was observed in the re-settled sediment. Conclusions: Sediment resuspension induced non-equilibrium conditions in the water column for more than 5 weeks and led to the enrichment with PCBs of the newly formed surface bed sediment. This enrichment was due to the preferential re-sorption of PCBs on clay-sized particles during the SRE and to the physical segregation and accumulation of the less dense particles at the surface of the sediment column; such particles thought to be the principal carriers of contaminants. These changes concerned <0.05 % of the total PCB content. © 2013 Springer-Verlag. Source

Grenier M.,SYMBHI | Monier T.,Artelia | Moiroud C.,CNR Institute of Neuroscience
Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2014 | Year: 2014

In the Romanche valley, near Grenoble in France, the combined risk of a flood occurring on the river and a landslide of several millions m3 (named the "Ruines de Séchilienne") threatens the safety of people living downstream. The SYMBHI is responsible for an operation that aims to take care of this risk, but not only: it also goes after including the other interests related to the river. This integrated project, concerning 9 municipalities and 20 000 inhabitants, thus plans developments on 10 kilometers of the river to guarantee protection of goods and people exposed, while improving environmental quality and functioning of aquatic associated ecosystems, and ensuring landscape insertion of the constructions on the banks. The project, designed by the companies Artelia and CNR, is currently in works phase. These works are scheduled to be completed by the end of 2015. © 2014 Taylor & Francis Group, London. Source

Lennock J.,Risk and Co | Gouley C.,Artelia
Society of Petroleum Engineers - SPE International Conference on Health, Safety and Environment 2014: The Journey Continues, HSE 2014 | Year: 2014

International discussions on corporate responsibility for the respect of human rights has increased significantly over the past few years culminating in the publication of the United Nations Guiding Principles on Business and Human Rights. Total has been an active contributor to these discussions and, in parallel, has developed internal guidance on human rights to complement existing policies on risk evaluation and Environmental and Social Impact Assessment (ESIA). A range of industry guidance has, and is, being developed on the integration of human rights into impact assessments, yet there remains discussion about whether an integrated, stand-alone or mixed approach can best address these issues. Total has identified the potential human rights risks and impacts of its exploration activities in a sub-saharan African country where the human rights context is particularly complex. A dual approach was taken: human rights issues were added to the scope of the ESIA, whilst in parallel a dedicated human rights impact assessment was commissioned. A number of issues have emerged: The relation between the potential impacts of a relatively small scale exploration activity in a context of high human rights risk; the need to address risks and impacts related to a specific operation versus those that go beyond a limited geographic zone; the 'conflict' between confidentiality for both the company and those stakeholders consulted, and transparency. This paper presents a comparative assessment of the methodologies used to identify potential human rights risks and impacts, evaluate their severity, and to identify mitigation measures. The strengths and weaknesses of each approach in this particular context are evaluated. It is anticipated that the assessment will provide lessons and practical recommendations for the industry given: The history and current human rights context in the operational area; the two studies being carried out in parallel for the same exploration activity in the same area, the different skills and experience being provided by the two organizations. Copyright © (2014) by the Society of Petroleum Engineers All rights reserved. Source

A general view of Ethiopia's Grand Renaissance Dam, as it undergoes construction, is seen during a media tour along the river Nile in Benishangul Gumuz Region, Guba Woreda, in Ethiopia March 31, 2015. According to a government official, the dam has hit the 41 percent... The three countries had initially picked French firm BRL and Dutch firm Deltares in April but Deltares later withdrew leading them to replace it with French firm Artelia on Tuesday. The leaders of the three countries signed a co-operation deal in Khartoum in March that paved the way for a joint approach to regional water supplies. Cairo and Addis Ababa had previously been locked in a bitter war of words over Ethiopia's $4 billion project. Tuesday's agreement came after talks between the foreign and water ministers of the three countries had to be extended for a third day. Technical studies will start in February, when the six ministers are due to meet again, and will take between six and 15 months, Sudanese Water Resources, Irrigation, and Electricity Minister Moataz Mousa said. The principles in the March agreement included giving priority to downstream countries for electricity generated by the dam, a mechanism for resolving conflicts, and providing compensation for damages. Signatories also pledged to protect the interests of downstream countries when the dam's reservoir is filled. Addis Ababa has long complained that Cairo was pressuring donor countries and international lenders to withhold funding from the 6,000 megawatt dam, which is being built by Italy's largest construction firm Salini Impregilo SpA. Egypt, which relies almost exclusively on the Nile for farming, industry and domestic water use, has sought assurances the dam will not significantly cut its flow to its rapidly growing population. Even before the impact studies have been started, officials say 50 percent of the dam's construction has been completed. "We are satisfied with the results of this meeting and look forward to achieving a strategic partnership," said Egyptian Foreign Minister Sameh Shoukry. Ethiopia, the source of the Blue Nile which joins the White Nile in Khartoum and runs on to Egypt, says the dam will not disrupt flow. It hopes the project will transform it into a power hub for the electricity-hungry region. "We see the agreement over these companies as progress and look forward to actualizing the interests of the three countries. We believe the dam will be useful to the three countries," said Ethiopian Foreign Minister Tedros Adhanom. The Grand Renaissance Dam is the centerpiece of Ethiopia's bid to become Africa's biggest power exporter. Addis Ababa plans to spend some $12 billion on harnessing its rivers for hydro power production in the next two decades.

Management of French Mediterranean rivers began early. However, since the second half of the last century they underwent greater disturbances than ever before that deeply affected their morphological equilibrium. The morphological analysis of a river generally postulates that it has reached a state of 'equilibrium'. But actually it is rarely true. Depending on the dynamism of the fluvial system, we can highlight three levels of action. Firstly, for morphologically active rivers, we can plan to restore a coherent morphological equilibrium at global spatial scale. Then, for poorly dynamic systems where the restoration of a global equilibrium is not possible at human temporal scale, a strategy of local management is used in order to restore an equilibrium locally. Finally, in specific cases, we can use keys to understanding provided the understanding keys given by the morphological approach. Source

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