Integrated Risk Assessment Research Articles

Design of fault trees as a practical method for risk analysis of CCS: Application to the different life stages of deep aquifer storage, combining long-term and short-term issues

INERIS (French National Institute for Industrial Environment and Risks) is involved in assessing accidental and chronic risks in industrial or underground activities. Concerning carbon dioxide storage, INERIS performs integrated risk assessment studies, by integrating both its know-how in industrial safety and the knowledge developed in the context of other underground storages: hydrocarbons, landfill, nuclear waste. Concerning the future development of the CCS technology, a major question is the underground evolution of the CO2 at medium and long time scales. It is necessary to undertake a systemic approach in order to consider all targets at stake and all stages of the CCS chain. INERIS developed a specific method that includes the tools that are used in environmental, health and safety risks. At first, a risk analysis was performed, leading to identify the relevant risk scenarios. There we took into account the possible high content of impurities, and therefore the different exposure routes for man and for the soil/water environment. 8 main 'Impacting phenomena' were defined, they cover the whole CCS chain (capture, transport, injection and long-term storage) and include both accidental and long-term effects. Each Impacting phenomenon gets a series of causes, that were represented in fault trees and were described in a dynamic graph through an adequate software tool. In a second step, the risk scenarios are to be quantified in terms of transfer and effects to the environment, and the estimated flows are to be compared to critical flows. This overall method consists of an integrated risk assessment, and helps in managing the risk for all life stages and all elements of the CCS chain, either at surface level or in the underground.

A decade of CO2 injection into depleting oil fields: Monitoring and research activities of the IEA GHG Weyburn-Midale CO2 Monitoring and Storage Project

Abstract Injection of CO 2 into the Weyburn Oil Field, Saskatchewan, Canada, began October 2000 and 10 years later approximately 18 MT of CO 2 will have been stored in the geological reservoir. The CO 2 injection is part of an ongoing enhanced oil recovery effort that will extend to 2035 and likely beyond. Both Weyburn and the adjacent Midale oil field are highly suitable for CO 2 -EOR and it is expected that, combined, more than 40 MT CO 2 will eventually be stored in these carbonate reservoirs. Currently about 2.4 MT and 0.4 MT CO 2 /year are being stored in the Weyburn and Midale fields, respectively, which now represent the largest site of monitored geological storage of CO 2 globally. The Weyburn Field is operated by Cenovus Energy and the Midale Field by Apache Canada. The anthropogenic CO 2 used at Weyburn-Midale is a by-product of coal gasification at the Great Plains Synfuels Plant in North Dakota, USA. The compressed CO 2 is delivered to the oil fields through a 323 km pipeline that crosses the international boundary. The IEA GHG Weyburn-Midale CO 2 Monitoring and Storage Project was established prior to the onset of CO 2 injection at Weyburn to assess monitoring methods and subsurface processes associated with the injection of CO 2 into geological storage sites. This research program is now in its second phase of research. Baseline 3D seismic surveys were performed over the Weyburn Field before injection and subsequent repeat 3D seismic surveys have been taken during the course of injection spanning multiple years and have indicated that CO 2 distribution within the reservoir can be imaged seismically. Similarly, repeat reservoir fluid sampling surveys have monitored a range of chemical and isotopic parameters to help identify processes associated with CO 2 -rock interaction. In addition, multiple soil gas and shallow hydrology surveys have been performed during the past 10 years with no indication of CO 2 reaching the surface. The current research program is building on many of the results obtained during the first phase of work on the Weyburn Field. For example, some of the current research includes applying stochastic methods to relate fluid chemistry to the seismic data to better characterize the distribution of CO 2 in the subsurface. Additional methods of modeling CO 2 distribution post-injection are also being demonstrated and integrated into several risk assessment methodologies. A detailed well database has been developed to catalogue characteristics associated with wells drilled at various stages of field development using different cementing practices and completion methods to assist with providing parameters for long-term modeling of well behaviour. In addition, a downhole well integrity testing program to examine cement sheath characteristics will be implemented in two wells in each of the fields. In summary, more than 30 research studies are being performed within this phase of the program to examine aspects of site characterization, well integrity, geochemical and geophysical monitoring methods and risk assessment. One of the goals for the work from this research program is to provide a best practices manual for the transition of CO 2 -EOR sites into storage sites. This paper provides an overview of the studies and results developing from the research program.

Well integrity risk assessment of Ketzin injection well (ktzi-201) over a prolonged sequestration period

Abstract Given the global interest in reducing greenhouse gas emissions, the 18 member CO2Sink consortium was formed to develop a pilot CO2 sequestration project near the town of Ketzin, Germany to advance the knowledge and understanding of CCS as a method of reducing CO2 emissions. This project includes 2 monitoring wells and 1 injection well, for a total injection of 30,000 tonnes of CO2. Among the projects associated with the Ketzin injection site, the COSMOS 2 research project was initiated as a partnership between France and Germany. The project includes, among others activities, the evaluation of the injection well (Ktzi-201) integrity. This was performed through extensive modeling using P&RTM approach and SIMEOTM Stor platform to simulate possible CO2 leakage along the wellbore over a 1,000-year period and a resulting risk assessment. Various case studies were tested: whereas risk levels tend to be low for a pilot project (i.e. low CO2 reservoir pressure), treatment actions could be required for industrial scale projects (i.e. greater CO2 reservoir pressure), such as additional characterizations, workovers, or an advanced abandonment strategy. These actions could decrease either the probability of the risk, or the severity, or both, ensuring effective CO2 confinement demonstration over the long-term. This study provides objective support in decisions regarding well management of the CO2 Ketzin project.

First steps in coupling continuous carbon isotopic measurements with already proven subsurface gas monitoring methods above underground carbon dioxide storage sites

The main role of INERIS (French National Institute for Industrial Environment and Risks) is to assess and avert accidental and chronic risks to both people and the environment linked to industrial installations, chemical substances and underground operations. INERIS is thus involved in research consortiums for underground storages of wastes, hydrocarbons or carbon dioxide. Concerning carbon dioxide storage, INERIS works for many years on defining and testing monitoring methods. As a French expert, the institute also performs integrated risk assessment studies. This paper focuses on the last improvements concerning the monitoring methods developed or patented by INERIS. Because the institute was created from the research centre of the former French national coal mining company, it has a well-established know-how in monitoring gas atmospheres. Having developed monitoring methods for mining contexts, INERIS has tools to constrain gas migrations in subsurface: 1. to determine gas flux between soil and atmosphere with dynamic accumulation chambers; 2. to determine gas concentrations in unsaturated zones through integrated gas sensor systems linked to subsurface boreholes (from 0 to about 300 meters depth). Initially designed for mining context, these two methods have been tested and proven for the monitoring of CO2 geological storage contexts. For example between 2005 and 2007, INERIS was one of the five partners involved in the 'GeoCarbone MONITORING' research project. This project was funded by the French Research Agency and aims at defining methods to monitor CO2 storage sites. Today the institute is involved in other projects studying pilot sites. In this paper we present results collected in analog contexts to CO2 storage sites. We will discuss in which conditions the carbon isotopic signature can help to determine the possible origins of the gas analyzed in our devices and to better understand the physical and chemical processes which can have led to the studied gas compositions. We will also highlight the fact that in some cases, there is a real need of using isotopic tracing methods otherwise the identification of these different processes cannot be done easily.

Inter-basin water transfer-supply model and risk analysis with consideration of rainfall forecast information

This paper develops a new inter-basin water transfer-supply and risk assessment model with consideration of rainfall forecast information. Firstly, based on the current state of reservoir and rainfall forecast information from the global forecast system (GFS), the actual diversion amount can be determined according to the inter-basin water transfer rules with the decision tree method; secondly, the reservoir supply operation system is used to distribute water resource of the inter-basin water transfer reservoir; finally, the integrated risk assessment model is built by selecting the reliability of water transfer, the reliability (water shortage risk), the resiliency and the vulnerability of water supply as risk analysis indexes. The case study shows that the inter-basin water transfer-supply model with rainfall forecast information considered can reduce the comprehensive risk and improve the utilization efficiency of water resource, as compared with conventional and optimal water distribution models.

Integrated risk assessment of a hydroxyapatite–protein-composite for use in oral care products: A weight-of-evidence case study

Risk assessment of cosmetic ingredients represents a regulatory standard requirement in Europe and other regions. An integrated approach was designed to assess the safety of HPC, a particulate composite of hydroxyapatite and protein (gelatin) for use in oral care products, employing a weight-of-evidence assessment and considering specific physico-chemical properties and exposure conditions. An initial evaluation of the constituents suggested that their chemical nature does not represent a particular health hazard per se. Hydroxyapatite is the main component of teeth and bones in mammals; gelatin is used in food and assumed to be safe once a BSE/TSE risk has been excluded. In vitro screening tests were chosen to further evaluate the biocompatibility: Hen’s egg test-chorioallantoic membrane (HET-CAM) to assess irritating effects towards mucous membranes; MTT cytotoxicity test with 3T3 fibroblasts; human corneal epithelial models to investigate inflammatory mediators and cytotoxicity; macrophage assays to measure cytotoxicity, inflammatory mediators and oxidative stress. Together with results from clinical studies, exposure estimates and analyses of kinetic properties, the presented information provides sound evidence to support the safe use of HPC. This is an example of a risk assessment for cosmetic use of small particles without the need for additional animal studies.

Advancing effects analysis for integrated, large-scale wildfire risk assessment

In this article, we describe the design and development of a quantitative, geospatial risk assessment tool intended to facilitate monitoring trends in wildfire risk over time and to provide information useful in prioritizing fuels treatments and mitigation measures. The research effort is designed to develop, from a strategic view, a first approximation of how both fire likelihood and intensity influence risk to social, economic, and ecological values at regional and national scales. Three main components are required to generate wildfire risk outputs: (1) burn probability maps generated from wildfire simulations, (2) spatially identified highly valued resources (HVRs), and (3) response functions that describe the effects of fire (beneficial or detrimental) on the HVR. Analyzing fire effects has to date presented a major challenge to integrated risk assessments, due to a limited understanding of the type and magnitude of changes wrought by wildfire to ecological and other nonmarket values. This work advances wildfire effects analysis, recognizing knowledge uncertainty and appropriately managing it through the use of an expert systems approach. Specifically, this work entailed consultation with 10 fire and fuels program management officials from federal agencies with fire management responsibilities in order to define quantitative resource response relationships as a function of fire intensity. Here, we demonstrate a proof-of-concept application of the wildland fire risk assessment tool, using the state of Oregon as a case study.

Determining Epidermal Disposition Kinetics for Use in an Integrated Nonanimal Approach to Skin Sensitization Risk Assessment

Development of risk assessment methods for skin sensitization in the absence of toxicological data generated in animals represents a major scientific and technical challenge. The first step in human skin sensitization induction is the transport of sensitizer from the applied dose on the skin surface to the epidermis, where innate immune activation occurs. Building on the previous development of a time course in vitro human skin permeation assay, new kinetic data for 10 sensitizers and 2 nonsensitizers are reported. Multicompartmental modeling has been applied to analyze the data and determine candidate dose parameters for use in integrated risk assessment methods: the area under the curve (AUC) and maximum concentration (C(max)) in the epidermis. A model with two skin compartments, representing the stratum corneum and viable skin (epidermis and dermis), was chosen following a formal model selection process. Estimates of the uncertainty, as well as average values of the epidermal disposition kinetics parameters, were made by fitting to the time course skin permeation data from individual skin donors. A potential reduced time course method is proposed based on two time points at 4 and 24 h, which gives results close to those from the full time course for the current data sets. The time course data presented in this work have been provided as a resource for development of predictive in silico skin permeation models.

The role of public sector asset managers in responding to climate change

PurposeThe purpose of this paper is to describe the current climate change predictions and the likely consequences for building assets, and therefore the delivery of public services, in the face of extreme weather events. Public sector asset managers need to mitigate and prepare for future events. However, current practice, as illustrated by the literature, shows that little risk assessment is currently undertaken.Design/methodology/approachThis paper is based on a literature review of current climate data and best practice asset management. An extensive survey of public sector asset managers working at senior levels in their organisation was designed and distributed to gather data on the current levels of disaster and business continuity planning. The survey design sought to establish the level of risk assessment across the organisations and the integration of property management into the disaster planning process.FindingsThis paper describes the current climate change predictions and the likely consequences for building assets in the face of extreme weather events. It reveals that a significant number of public sector authorities are not preparing integrated disaster management plans nor business continuity plans. There is a need for further research into the impact on assets and the role of the public sector real estate manager in assessing the risks and developing strategies to prepare the organisation and to mitigate the effects of natural disasters and severe weather events.Originality/valueThis research highlights the potential for climate change to threaten property assets and particularly to compromise the delivery of public services in the event of extreme weather events. The paper highlights the need for integrated risk assessment and disaster planning, which incorporates enabling property assets. Public sector asset managers have a vital role to play in undertaking risk assessment and preparing disaster plans. This role is becoming increasingly important as climate change is predicted to have a significant effect on the frequency of extreme weather events and the occurrence of natural disasters.

Risk assessment study for water supply network using GIS

In recent years, contamination of water in water distribution systems (WDS) has been recognized as a major cause of waterborne diseases. Owing to old and deteriorated pipes, and the presence of pollution sources in contact with the supply line, water boards often decide to replace the network in the interests of public health. This being a cost-intensive and time-consuming programme, decision makers need a basis for phase-wise investment planning. In view of this, Integrated Risk Assessment of Water Distribution System (IRA-WDS) for the supply network of Adikmet Subzone-I in Hyderabad, India, was undertaken. GIS maps were prepared for the water supply network, sewer network, open drains, soil and groundwater table at 1:2,200 scale and ‘pipe condition assessment’ and identification of ‘contaminant ingress’ locations were performed using IRA-WDS. Findings indicated 18 pipes in ‘very bad’ and ‘bad’ condition in the entire network. ‘High risk’ of contamination was exhibited in 20 locations, suggesting the need for rehabilitation of only 2 to 3% of pipes in the initial phase.

Revisiting the rationale for holistic, integrated risk assessments

Revisiting the rationale for holistic, integrated risk assessments

Assessing natural hazards in forestry for risk management: a review

We address the problem of how to integrate risk assessment into forest management and therefore provide a comprehensive review of recent and past literature on risk analysis and modeling and, moreover, an evaluation and summary on these papers. We provide a general scheme on how to integrate concepts of risk into forest management decisions. After an overview of the risk management process and the main hazards in forests (storm, snow, insects, fire), the paper focuses on the principal methods used to assess risks from these hazards for commercial forestry. We review mechanistic models, empirical models, and expert systems and consider the needs for different spatial scales of risk assessment, from the regional to the single-tree level. In addition to natural hazards and their secondary effects, we deal with economic aspects of risk analysis. Monte Carlo simulations to deal with volatile timber prices and ways to include risk in classical Faustmann approaches are briefly discussed along with the integration of portfolio theory into forest management decision making and attitude toward risk. Special attention is paid to the implications for risk modeling under climate change.

An integrated risk assessment for climate change: analysing the vulnerability of sharks and rays on Australia's Great Barrier Reef

AbstractAn Integrated Risk Assessment for Climate Change (IRACC) is developed and applied to assess the vulnerability of sharks and rays on Australia's Great Barrier Reef (GBR) to climate change. The IRACC merges a traditional climate change vulnerability framework with approaches from fisheries ecological risk assessments. This semi‐quantitative assessment accommodates uncertainty and can be applied at different spatial and temporal scales to identify exposure factors, at‐risk species and their key biological and ecological attributes, critical habitats a`nd ecological processes, and major knowledge gaps. Consequently, the IRACC can provide a foundation upon which to develop climate change response strategies. Here, we describe the assessment process, demonstrate its application to GBR shark and ray species, and explore the issues affecting their vulnerability to climate change. The assessment indicates that for the GBR, freshwater/estuarine and reef associated sharks and rays are most vulnerable to climate change, and that vulnerability is driven by case‐specific interactions of multiple factors and species attributes. Changes in temperature, freshwater input and ocean circulation will have the most widespread effects on these species. Although relatively few GBR sharks and rays were assessed as highly vulnerable, their vulnerability increases when synergies with other factors are considered. This is especially true for freshwater/estuarine and coastal/inshore sharks and rays. Reducing the impacts of climate change on the GBR's sharks and rays requires a range of approaches including mitigating climate change and addressing habitat degradation and sustainability issues. Species‐specific conservation actions may be required for higher risk species (e.g. the freshwater whipray, porcupine ray, speartooth shark and sawfishes) including reducing mortality, preserving coastal catchments and estuarine habitats, and addressing fisheries sustainability. The assessment identified many knowledge gaps concerning GBR habitats and processes, and highlights the need for improved understanding of the biology and ecology of the sharks and rays of the GBR.

A trustworthiness-based distribution model for data leakage prevention

Under the global circumstances where data leakage gets more and more severe, we present a trustworthiness-based distribution model that aims at data leakage prevention (DLP). In our model, first, the distributor calculates the user’s trustworthiness based on his historical behaviors; second, according to the user’s trustworthiness and his obtained file set overlapping leaked file set, the distributor accesses the probability of the user’s intentional leak behavior as the subjective risk assessment; third, the distributor evaluates the user’s platform vulnerability as an objective element; last, the distributor makes decisions whether to distribute the file based on the integrated risk assessment. The experiments indicate that the model can distinguish users of different types and make the probability of malicious users’ requirements being denied much higher than that of honest users’ requirements being denied, so that the model is capable of preventing data leakage validly.

Beyond REACH: Roadblocks and shortcuts en route to integrated risk assessment and management of chemicals

This paper addresses obstacles and opportunities for the development and application of novel methods for integrated assessment of cumulative risks from chemicals, exemplified by the REACH legislation of the EU, in the context of multiple stressors and of chemicals policy. We examine the role of such methods in connection with REACH by models of integration and innovation of risk information in multi-actor risk governance; analyses of key documents on REACH; and interviews with EU regulators and stakeholders. We first explain the emergence of REACH as a response to tensions in EU chemicals, environmental and other policies. We then analyze the present configuration of REACH particularly in relation to key dimensions of risk integration: across stressors; exposed organisms; and impacts. Among the policy aspects of integrated risk information, we focus on its interaction with management and the contesting framings and interpretations of assessment. Avenues and barriers are identified for integrated treatment of risks under REACH and with other instruments. We emphasize how bounded, formal and static assessments interact with open and informal approaches that have more flexibility in integrating risks in new ways. We conclude with a generalizing discussion on the role of novel methods of integrated risk assessment in the development of reflexive and participatory governance under REACH and beyond.

Integrated risk assessment of household chemicals and consumer products: Addressing concerns about triclosan

Integrated risk assessment of household chemicals and consumer products: Addressing concerns about triclosan

Interactions between toxic chemicals and natural environmental factors — A meta-analysis and case studies

The paper addresses problems arising from effects of natural environmental factors on toxicity of pollutants to organisms. Most studies on interactions between toxicants and natural factors, including those completed in the EU project NoMiracle (Novel Methods for Integrated Risk Assessment of Cumulative Stressors in Europe) described herein, showed that effects of toxic chemicals on organisms can differ vastly depending purely on external conditions. We compiled data from 61 studies on effects of temperature, moisture and dissolved oxygen on toxicity of a range of chemicals representing pesticides, polycyclic aromatic hydrocarbons, plant protection products of bacterial origin and trace metals. In 62.3% cases significant interactions ( p ≤ 0.05 or less) between natural factors and chemicals were found, reaching 100% for the effect of dissolved oxygen on toxicity of waterborne chemicals. The meta-analysis of the 61 studies showed that the null hypothesis assuming no interactions between toxic chemicals and natural environmental factors should be rejected at p = 2.7 × 10 − 82 (truncated product method probability). In a few cases of more complex experimental designs, also second-order interactions were found, indicating that natural factors can modify interactions among chemicals. Such data emphasize the necessity of including information on natural factors and their variation in time and across geographic regions in ecological risk assessment. This can be done only if appropriate ecotoxicological test designs are used, in which test organisms are exposed to toxicants at a range of environmental conditions. We advocate designing such tests for the second-tier ecological risk assessment procedures.

Integrated risk assessment and risk governance as socio-political phenomena: A synthetic view of the challenges

To call for integration in risk assessment and governance as a self-evident goal is deceptively easy. For more insight, we ask: what level and kind of integration and for what purposes is needed and sufficient? What opportunities and obstacles can be identified for integrative treatment of risks? What causes and impacts are there of developments in risk integration? To answer these questions we investigate the socio-political processes and factors surrounding integrated risk assessment and risk governance through a combination of literature reviews and original research. We emphasize regulatory assessment and governance of risks associated with chemicals in the EU, but we link them with other areas to better grasp options and problems in integration. We relate the problems to political factors and barriers in sector and vertical integration, including deviating interests, and further to conflicting information, concepts and mindsets. Risk assessment and risk governance involve varying notions of risks and knowledge, with tensions between stressor- or impact-oriented, exclusive or inclusive, positivist or relativist, and fixed or reflexive notions and approaches. These tensions influence the trajectories of integration between sectors, actors and regions, constraining the fulfillment of ideals of integrated governance. We conclude that risk assessment and governance can be integrated, harmonized and innovated to a limit only, but this limit is variable and flexible, and provides opportunities especially if attention is paid to the socio-political contexts, value choices and decision structures in each case. Generally, the results underline a reflexive approach whereby the meanings, framings and implications of risk integration are probed in open processes of deliberation and negotiation, as a learning process to transcend the formal and prescriptive modes of regulation and knowledge generation.

GLOBAL NETWORKING FOR BIODOSIMETRY LABORATORY CAPACITY SURGE IN RADIATION EMERGENCIES

For the public health management of radiation emergencies, one of the essential components of integrated risk assessment is to quickly and accurately assess and categorize the exposure. In addition to other methods, biodosimetry is instrumental to support decision-making for: 1) efficient secondary triage in a hospital response phase; 2) multi-parameter approach for defining best-treatment strategies for those severely exposed; 3) clinical prognosis and assessment of risk; and 4) reassurance and psychological support for those potentially exposed, or "worried-well." In large-scale events, the number of victims, and especially those worried-well, is likely to overwhelm hospital and laboratory capacities in the accident area. This is already being addressed through the networking approach within several countries and/or regions of the world. The paper reports about WHO's activity toward coordination of these regional efforts and the international collaborative network of biodosimetry laboratory services, WHO BioDoseNet. The network includes more than 30 laboratories around the world and supports the implementation of the revised International Health Regulations, the scope of which since 2007 also covers the field of radionuclear incidents.

Towards a combined prognostic index for survival in HIV infection: the role of 'non-HIV' biomarkers.

As those with HIV infection live longer, 'non-AIDS' condition associated with immunodeficiency and chronic inflammation are more common. We ask whether 'non-HIV' biomarkers improve differentiation of mortality risk among individuals initiating combination antiretroviral therapy (cART). Using Poisson models, we analysed data from the Veterans Aging Cohort Study (VACS) on HIV-infected veterans initiating cART between 1 January 1997 and 1 August 2002. Measurements included: HIV biomarkers (CD4 cell count, HIV RNA and AIDS-defining conditions); 'non-HIV' biomarkers (haemoglobin, transaminases, platelets, creatinine, and hepatitis B and C serology); substance abuse or dependence (alcohol or drug); and age. Outcome was all cause mortality. We tested the discrimination (C statistics) of each biomarker group alone and in combination in development and validation data sets, over a range of survival intervals, and adjusting for missing data. Of veterans initiating cART, 9784 (72%) had complete data. Of these, 2566 died. Subjects were middle-aged (median age 45 years), mainly male (98%) and predominantly black (51%). HIV and 'non-HIV' markers were associated with each other (P < 0.0001) and discriminated mortality (C statistics 0.68-0.73); when combined, discrimination improved (P < 0.0001). Discrimination for the VACS Index was greater for shorter survival intervals [30-day C statistic 0.86, 95% confidence interval (CI) 0.80-0.91], but good for intervals of up to 8 years (C statistic 0.73, 95% CI 0.72-0.74). Results were robust to adjustment for missing data. When added to HIV biomarkers, 'non-HIV' biomarkers improve differentiation of mortality. When evaluated over similar intervals, the VACS Index discriminates as well as other established indices. After further validation, the VACS Index may provide a useful, integrated risk assessment for management and research.