Gaël Bellenfant | BRGM - Academia.edu (original) (raw)

Papers by Gaël Bellenfant

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Proceedings of the International Conference on Mine Closure, 2019

The current paradigm in mine closure is continuous, or progressive, mine closure, which is the in... more The current paradigm in mine closure is continuous, or progressive, mine closure, which is the industry standard for best closure outcomes. However, this is a complex management challenge because mine closure is a long, evolving process that can be hampered by changes in ownership and management. It involves external stakeholders, and the jointly planned post-closure land uses influence all closure plans and actions. Closure is also an official process with regulatory requirements and financial sureties. Continuous closure also means continuous reduction of unknowns, risks and (financial) liabilities. Therefore, the constant accumulation of data and plans and the whole process need to be well documented. Such a complex undertaking needs tools that help in managing the process. We must take this beyond the conventional closure management plans (CMPs) written on paper to a digital system with enhanced capabilities for continuous closure management. At the same time, the authorities are going digital. Some European Union Member States and other countries around the world have set up, and are pursuing, e-government initiatives that are designed to help interaction with the authorities when applying for permits and licences, and submitting environmental impact assessments, etc. (EIAs) (e.g. the digital permit process management system in Germany called BergPass). This also concerns mining projects and the closure of mines. This development also means that CMPs need to comply with these systems, which also emphasises the need for digital closure management systems such as Closurematic: Management Tool for Continuous Mine Closure. The Closurematic project (2018-2021), funded by the European Institute of Innovation and Technology on RawMaterials (EIT RM), is creating a new digital system for managing the mine closure process. Closurematic is a versatile digital tool to help mining companies and consultants plan, carry out, manage, monitor, communicate, and document mine closure at every step of a mining project. The tool adds value to a mining company's assets by creating continuity in the long-term management of closure-related data. Its main functions will include an easily adaptable master plan (using tailored templates), extended interactive guidance to help the user, links to the best international practices, a geographic information system (GIS) interface, a file repository to store documents relating to the closure, and interactive tables and charts to monitor the closure actions and associated costs.

HAL (Le Centre pour la Communication Scientifique Directe), Jun 13, 2019

Pour

Merci de ne rien inscrire dans cette zone et ne pas modifier les marges des pieds de page et entê... more Merci de ne rien inscrire dans cette zone et ne pas modifier les marges des pieds de page et entêtes. Ne rien inscrire dans cette zone et ne pas modifier les marges des pieds de page et entêtes sans quoi votre résumé sera systématiquement refusé Merci de ne rien inscrire dans cette zone et ne pas modifier les marges des pieds de page et entêtes.

Environnement, Ingénierie & Développement, 2010

L’objectif de cet article est de présenter les résultats d’une modélisation des impacts potentiel... more L’objectif de cet article est de présenter les résultats d’une modélisation des impacts potentiels sur la qualité des eaux souterraines liés à l’utilisation de matériaux alternatifs ou hors spécifications en sous couches routières ou en parking. Ces impacts potentiels ont été calculés dans le cadre des travaux du groupe de travail relatif à l'acceptabilité de matériaux alternatifs ou hors spécifications en techniques routières, mis en place par le Ministère de l’Ecologie de l’Energie du Développement Durable et de l’Aménagement du Territoire (MEEDDAT). Cet article présente les résultats de plusieurs scénarios d’utilisation : assise de chaussée de voirie ; assise de chaussée de parking ; remblai technique.Les modélisations ont été effectuées avec les codes de calcul du domaine public ModFLOW 2000 de l’USGS (pour la simulation des écoulements) et MT3DMS de l’US EPA (pour la simulation et le transport des polluants) en considérant 2 configurations hydrologiques, ainsi qu’une rechar...

Le Centre pour la Communication Scientifique Directe - HAL - Université de Nantes, Aug 24, 2015

En France, l'exploitation d'un grand nombre de mines a genere le stockage d'important... more En France, l'exploitation d'un grand nombre de mines a genere le stockage d'importantes quantites de « dechets miniers », qu'il s'agisse de la gangue ecartee a l'issue des etapes de comminution, des residus de traitements mineralurgiques (etapes de concentration) ou hydro-metallurgiques ou encore des scories recuperees a l'issue des eventuels traitements par pyrometallurgie. Dans certains cas, ces residus contiennent des metaux rares (gallium, germanium, indium, terres-rares, tungstene…), desormais juges strategiques, voire critiques, et recherches pour des applications a haute valeur ajoutee. Ces metaux soit n'etaient pas extraits par le passe, soit etaient exploites au moyen de techniques dont les performances ont largement evolue, laissant egalement des metaux de base residuels. Par ailleurs, ces sites, du fait notamment d'un impact sur l'environnement (relargage particulaire et de metaux, drainages miniers, acides ou non,…), peuvent necess...

First EAGE CO2 Geological Storage Workshop, 2008

Soft Methods for Handling Variability and Imprecision

In recent years, soft methods for treating uncertainties have reached the field of environmental ... more In recent years, soft methods for treating uncertainties have reached the field of environmental risks. This paper presents some specific characteristics of this field and how they can affect the choice of methods and the way of representing results. Example ...

Energy Procedia, 2009

The development of a methodology for defining safety criteria for CO 2 geological storage, realis... more The development of a methodology for defining safety criteria for CO 2 geological storage, realised under the ongoing CRISCO2 project, is depicted in this paper. Generic lists of eleven risk events and nine types of targets are proposed to serve an expert panel for identifying risk scenarios. Assessing the effects of risk events and comparing targets exposure to critical thresholds should lead to setting safety requirements. We focus on simple modelling, such as abacuses, analytical or semi-analytical models. An uncertainty management framework completes this methodology. Further work will concentrate on effectively deducing safety criteria.

Energy Procedia, 2011

For carbon dioxide capture and storage to make an effective contribution in reducing greenhouse g... more For carbon dioxide capture and storage to make an effective contribution in reducing greenhouse gas emissions, a large number of storage sites will be required. Safety will have to be demonstrated for each of these sites. We present in this paper a simple and flexible framework to assess safety of a CO 2 storage site in a time-efficient manner. It includes the identification by an expert panel of the relevant risk scenarios. Their evaluation privileges analytical or semi-analytical modelling with conservative assumptions. Uncertainty is managed in order to thoroughly represent and propagate the nature of information relative to the site properties. We illustrate the application of this framework with a case study in the context of the Paris Basin. The workflow described is not a complete risk assessment framework, but it constitutes a useful tool for an operator at an early stage of a project or to iteratively screen safety issues, or for a regulating authority to review the safety conditions of a project.

Transport in Porous Media, 2011

This article presents a numerical modeling application using the code TOUGHREACT of a leakage sce... more This article presents a numerical modeling application using the code TOUGHREACT of a leakage scenario occurring during a CO 2 geological storage performed in the Jurassic Dogger formation in the Paris Basin. This geological formation has been intensively used for geothermal purposes and is now under consideration as a site for the French national program of reducing greenhouse gas emissions and CO 2 geological storage. Albian sandstone, situated above the Because of CPU time and memory constraints, approximation and simplification regarding the geometry of the geological structure, the mineralogical assemblages and the injection period (up to 5 years) have been applied to the system, resulting in limited analysis of the estimated impacts. The CO 2 migration rate and the quantity of CO 2 arriving as free gas and dissolving, firstly in the storage water and secondly in the water of the overlying aquifer, are calculated. CO 2 dissolution into the Dogger aquifer induces a pH drop from about 7.3 to 4.9 limited by calcite dissolution buffering. Glauconite present in the Albian aquifer also dissolves, causing an increase of the silicon and aluminium in solution and triggering the precipitation of kaolinite and quartz around the intrusion point. A sensitivity analysis of the leakage rate according to the location of the leaky well and the variability of the petro-physical properties of the reservoir, the leaky well zone and the Albian aquifers is also provided.

Renewable Energy, 2011

Biogas produced from anaerobic fermentation of organic substances represents an alternative renew... more Biogas produced from anaerobic fermentation of organic substances represents an alternative renewable energy source. Its utilization would contribute to substantial reduction of the solid waste volume in land-filling and incineration. Biogas so produced could be utilized on site or it could be injected into the natural gas distribution network. Microbiological and chemical compositions of different biogas types were determined in order to conduct qualitative and quantitative risk assessments of the potential health hazards associated with biogas use for cooking. Biogas types that could be allowed for injection in the natural gas pipelines were listed with recommendations, while outlining the European biogas injection policy. Results indicated that the injection of the processed biogas in the distribution network did not present any additional chemical or microbiological risk to consumers when compared to natural gas, provided that the biogas resulted from the fermentation of non-dangerous waste. However, since this study did not examine the microbiological and chemical composition of biogas originating from wastewater sludges and/or industrial wastes, the injection of this type of biogas into the gas distribution network should not be allowed unless a similar risk evaluation study is conducted for each case.

Energy Procedia, 2009

We use the IRS (Independent Random Set) method to combine both aleatory and epistemic uncertainti... more We use the IRS (Independent Random Set) method to combine both aleatory and epistemic uncertainties in the prediction, by means of an analytical model, of CO 2 plume extension during geological storage. While some model parameters can be handled within a classical probability framework, due to the availability of data, other parameters are dealt with using possibility theory, due to the imprecise/incomplete nature of the available information. Results of calculated CO 2 plume extension are presented in terms of distributions of the upper and lower probability that plume migration distance lies below a certain value. In a decisionmaking framework, these results could be combined into a single distribution, referred to here as a "confidence index", such as a weighted average of upper (optimistic) and lower (pessimistic) probabilities that migration distance is below a certain value. The selected weight reflects the decision-maker's degree of "risk aversion".

The EGU General Assembly, 2014

The question of storing energy in France has become of primary importance since the launch of a r... more The question of storing energy in France has become of primary importance since the launch of a road map from the government which places in pole position this topic among seven major milestones to be challenged in the context of the development of innovative technology in the country. The European objective to reach 20% of renewables in the energy market, from which a large part would come from wind and solar power generation, raises several issues regarding the capacity of the grid to manage the various intermittent energy sources in line with the variability of the public demand and offer. These uncertainties are highly influenced by unpredictable weather and economic fluctuations. To facilitate the large-scale integration of variable renewable electricity sources in grids, massive energy storage is needed. In that case, electric energy storage techniques involving the use of underground are often under consideration as they offer a large storage capacity volume with a adapted po...

Proceedings of the International Conference on Mine Closure, 2019

HAL (Le Centre pour la Communication Scientifique Directe), Jun 13, 2019

Pour

Environnement, Ingénierie & Développement, 2010

Le Centre pour la Communication Scientifique Directe - HAL - Université de Nantes, Aug 24, 2015

First EAGE CO2 Geological Storage Workshop, 2008

Soft Methods for Handling Variability and Imprecision

Energy Procedia, 2009

Energy Procedia, 2011

Transport in Porous Media, 2011

Renewable Energy, 2011

Energy Procedia, 2009

The EGU General Assembly, 2014