Assessing the Risk of Contaminant Dispersion From Fibrous Sediments of Industrial Origin

Unregulated discharges of wastewater from pulp and paper factories resulted in the formation of relatively thick organic (cellulose) rich sediments in shallow waters along the Swedish coast. These deposits are known as fiberbanks and are contaminated by persistent organic pollutants (POPs), metals and methylmercury, which can be dispersed by diffusion and advective processes coupled to propeller wash, high river discharges, strong wind waves and submarine landslides. Based on a case study of polychlorinated biphenyls (PCBs), one group of prevalent POPs in the fiberbanks, we present a probabilistic approach to estimate the potential risk of dispersion of fiberbank contaminants. The approach allows for estimation of the dispersal pathways that dominates the risk within a given time and provides more insight about the significance of various dispersion processes. We show that it is highly likely that chemical diffusion and advection triggered by ship-induced resuspension will disperse PCBs (sum of seven congeners; Σ7PCB) above a threshold level for environmental impact, while the likelihood of river and wind-wave generated resuspension dispersion pathways are lower (∼20%, respectively). We further show that there is approximately 5% likelihood that a submarine landslide will disperse Σ7PCB above the threshold level. The study implies that the governing parameters for risk assessment specifically should include reliable data on contaminant concentration, water depth above the fiberbank, estimation of concerned fiberbank areas, time duration of erosive fluid flows and measured diffusion. The approach provides insight into the importance of various dispersion processes. We suggest that it can be applied to support risk assessment, especially when there are limited available data and/or knowledge about the system under study.

Download Full-text

Probability risk assessment of landslides: A case study at Finneidfjord

Canadian Geotechnical Journal ◽

10.1139/t08-055 ◽

2008 ◽

Vol 45 (9) ◽

pp. 1250-1267 ◽

Cited By ~ 31

Author(s):

Mark J. Cassidy ◽

Marco Uzielli ◽

Suzanne Lacasse

Keyword(s):

Risk Assessment ◽

Probabilistic Approach ◽

Quantitative Risk Assessment ◽

Historical Case Study ◽

Historical Case ◽

Second Moment ◽

Integrated Risk Assessment ◽

First Order Second Moment ◽

Probabilistic Risk Assessments

Probabilistic risk assessments are increasingly being considered the most appropriate framework for engineers to systematically base decisions on hazard mitigation issues. This paper aims to show the advantages of a quantitative risk assessment by application to a historical case study. The generalized integrated risk assessment framework has been applied retrospectively to a submarine landslide that occurred in 1996 near the village of Finneidfjord in northern Norway. Over 1 million cubic metres of predominantly quick clay was displaced. Even though it was triggered underwater on the embankment of the Sørfjord, the retrogressive nature of the slide resulted in it encroaching 100–150 m inland. The triggering mechanism is believed to have been the placement of fill, from a nearby tunnelling project, on the foreshore of the embankment. This paper is a retrospective quantitative evaluation of the risk to the neighbouring houses, the persons in those houses, and the persons in open spaces caused by the placement of increasing levels of embankment fill. A probabilistic approach, making use of second-moment modelling and first-order second-moment approximation is adopted. It aims to demonstrate the advantages of this type of risk assessment in understanding complex and integrated hazards, particularly those in populated environments.

Download Full-text

Quantitative Risk Assessment of Population Affected by Tropical Cyclones through Joint Consideration of Extreme Precipitation and Strong Wind—A Case Study of Hainan Province

Earth s Future ◽

10.1029/2021ef002365 ◽

2021 ◽

Author(s):

Chenna Meng ◽

Wei Xu ◽

Yu Qiao ◽

Xinli Liao ◽

Lianjie Qin

Keyword(s):

Risk Assessment ◽

Tropical Cyclones ◽

Extreme Precipitation ◽

Quantitative Risk Assessment ◽

Hainan Province ◽

Strong Wind ◽

Joint Consideration

Download Full-text

Multi-hazard risk assessment for roads: probabilistic versus deterministic approaches

Natural Hazards and Earth System Science ◽

10.5194/nhess-20-3135-2020 ◽

2020 ◽

Vol 20 (11) ◽

pp. 3135-3160

Author(s):

Stefan Oberndorfer ◽

Philip Sander ◽

Sven Fuchs

Keyword(s):

Risk Assessment ◽

Road Safety ◽

Input Data ◽

Probabilistic Approach ◽

Transport Infrastructure ◽

Data Uncertainty ◽

European Alps ◽

Hazard Risk ◽

The Impact

Abstract. Mountain hazard risk analysis for transport infrastructure is regularly based on deterministic approaches. Standard risk assessment approaches for roads need a variety of variables and data for risk computation, however without considering potential uncertainty in the input data. Consequently, input data needed for risk assessment are normally processed as discrete mean values without scatter or as an individual deterministic value from expert judgement if no statistical data are available. To overcome this gap, we used a probabilistic approach to analyse the effect of input data uncertainty on the results, taking a mountain road in the Eastern European Alps as a case study. The uncertainty of the input data are expressed with potential bandwidths using two different distribution functions. The risk assessment included risk for persons, property risk and risk for non-operational availability exposed to a multi-hazard environment (torrent processes, snow avalanches and rockfall). The study focuses on the epistemic uncertainty of the risk terms (exposure situations, vulnerability factors and monetary values), ignoring potential sources of variation in the hazard analysis. As a result, reliable quantiles of the calculated probability density distributions attributed to the aggregated road risk due to the impact of multiple mountain hazards were compared to the deterministic outcome from the standard guidelines on road safety. The results based on our case study demonstrate that with common deterministic approaches risk might be underestimated in comparison to a probabilistic risk modelling setup, mainly due to epistemic uncertainties of the input data. The study provides added value to further develop standardized road safety guidelines and may therefore be of particular importance for road authorities and political decision-makers.

Download Full-text

A two-stage probabilistic approach for the risk assessment of submarine landslides induced by gas hydrate exploitation

Applied Ocean Research ◽

10.1016/j.apor.2020.102158 ◽

2020 ◽

Vol 99 ◽

pp. 102158

Author(s):

Yangming Chen ◽

Lulu Zhang ◽

Chencong Liao ◽

Mingjing Jiang ◽

Ming Peng

Keyword(s):

Risk Assessment ◽

Gas Hydrate ◽

Probabilistic Approach ◽

Submarine Landslides ◽

Two Stage

Download Full-text

A PROBABILISTIC APPROACH TO ECOLOGICAL RISK ASSESSMENT: A CASE STUDY OF THERMAL DISCHARGES INTO LAKE WATER ENVIRONMENT

Proceedings of the Water Environment Federation ◽

10.2175/193864704790896252 ◽

2004 ◽

Vol 2004 (4) ◽

pp. 134-146

Author(s):

Jhapendra Pokhrel

Keyword(s):

Risk Assessment ◽

Ecological Risk ◽

Ecological Risk Assessment ◽

Lake Water ◽

Probabilistic Approach ◽

Water Environment

Download Full-text

Probabilistic approach for the risk assessment of nanomaterials: A case study for graphene nanoplatelets

International Journal of Hygiene and Environmental Health ◽

10.1016/j.ijheh.2018.08.011 ◽

2019 ◽

Vol 222 (1) ◽

pp. 76-83 ◽

Cited By ~ 4

Author(s):

Andrea Spinazzè ◽

Andrea Cattaneo ◽

Francesca Borghi ◽

Luca Del Buono ◽

Davide Campagnolo ◽

...

Keyword(s):

Risk Assessment ◽

Probabilistic Approach ◽

Graphene Nanoplatelets

Download Full-text

An Overview of Risk-Based EEE Counterfeit Part Detection Based on SAE AS6171

10.31399/asm.cp.istfa2018p0051 ◽

2018 ◽

Author(s):

Michael H. Azarian

Keyword(s):

Risk Assessment ◽

Multiple Solutions ◽

Test Equipment ◽

Assessment Methodology ◽

Test Plan ◽

Specific Test ◽

Risk Assessment Methodology

Abstract As counterfeiting techniques and processes grow in sophistication, the methods needed to detect these parts must keep pace. This has the unfortunate effect of raising the costs associated with managing this risk. In order to ensure that the resources devoted to counterfeit detection are commensurate with the potential effects and likelihood of counterfeit part usage in a particular application, a risk based methodology has been adopted for testing of electrical, electronic, and electromechanical (EEE) parts by the SAE AS6171 set of standards. This paper provides an overview of the risk assessment methodology employed within AS6171 to determine the testing that should be utilized to manage the risk associated with the use of a part. A scenario is constructed as a case study to illustrate how multiple solutions exist to address the risk for a particular situation, and the choice of any specific test plan can be made on the basis of practical considerations, such as cost, time, or the availability of particular test equipment.

Download Full-text