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The benefits of quantitative risk assessments for landslide management have been discussed and illustrated in several publications. However, there still are some challenges in its application for low-probability, high-magnitude events. These challenges are associated with the difficulties in populating our models for risk calculations, which largely require the input of expert opinion. This paper presents a quantitative risk assessment to a very slow moving rock slope within a dam reservoir in the Province of British Columbia, Canada. The assessment is focused on the risk to the population in the vicinity of the dam and the populated areas downstream. Expert opinions quantified the slope failure probabilities in the order of 10 to 10 per year for the smallest failure scenario considered and less than 10 for a failure of the entire slope. However, these estimations are associated with high levels of uncertainty. Our approach starts with the calculation and assessment of the magnitude and probability of the potential slope failure consequences, minimizing the uncertainties associated with estimated slope failure probabilities. Then, these consequences and failure probabilities are combined to obtain a measure of risk. The uncertainty associated with the slope failure probabilities is managed by the estimation of plausible ranges for these. The calculated risk levels are then presented as ranges of values and assessed against adopted evaluation criteria. The consequence and risk assessment of the rock slope suggest that the risk to the population exposed in the vicinity of the dam and populated areas downstream is under adequate control. The probability of large consequence scenarios is extremely low, in the order of 10 chance of an event causing more than 100 fatalities. We propose an observational technique to assess changes in risk levels and decide when to update the risk management approach or deploy emergency measures. The technique is focused on the detection of changes in the slope deformation patterns that would indicate an increase in the potential failure volumes or an imminent failure. It can be considered an extension to the current early warning system in place, easy to implement and enhanced with the strength of the comprehensive analysis required for a quantitative risk assessment. [ABSTRACT FROM AUTHOR]

Railways across the Canadian Cordillera have long histories of losses associated with ground hazards. The hazards most frequently reported are rockfalls, which are ubiquitous along the steep rock cuts required to accommodate the railway alignment. Several hazard control measures can be adopted in rockfall areas. However, when rockfall frequencies cannot be controlled, protective structures may be necessary to decrease rockfall-related risks to tolerable levels. Designs of protective structures require knowing rockfall trajectory heights and kinetic energies. This information is difficult to obtain even at locations where comprehensive rockfall records are kept. We present a method to calculate rockfall trajectory heights and velocities based on three-dimensional, lumped mass, rockfall simulations. Rockfall source location, model parameters and model calibration are also discussed. In this regard, the model should be calibrated against observed values of rockfall heights and velocities, and the design parameters should be validated before proceeding with the design of rockfall mitigation measures. The method is illustrated with the analysis of a section of a railway along the Canadian Cordillera. Furthermore, a probabilistic approach is adopted to calculate rockfall trajectory heights and velocities when intersecting the railway alignment. This is consistent with the natural variability of rockfall trajectories and falling block volumes. We illustrate the use of probability distributions of rockfall velocities and volumes to calculate the distribution of kinetic energy at three locations along the study section. The calculated rockfall trajectory heights are also presented in probabilistic terms and discussed. The rockfall kinetic energy distributions are used to assess the type of protective structures that could be required for further reduction of risk levels. [ABSTRACT FROM AUTHOR]

Intellectual disabilities (ID) are conditions originating before the age of 18 that result in significant limitations in intellectual functioning and conceptual, social and practical adaptive skills. IDs affect 1 to 3% of the population. Persons with ID are more likely to have physical disabilities, mental health problems, hearing impairments, vision impairments and communication disorders. These co-existing disabilities, combined with the limitations in intellectual functioning and in adaptive behaviours, make this group of Canadians particularly vulnerable to health disparities. The purpose of this synthesis article is to explore potential contributory factors to health vulnerabilities faced by persons with ID, reveal the extent and nature of health disparities in this population, and examine initiatives to address such differences. The review indicates that persons with ID fare worse than the general population on a number of key health indicators. The factors leading to vulnerability are numerous and complex. They include the way society has viewed ID, the etiology of ID, health damaging behaviours, exposure to unhealthy environments, health-related mobility and inadequate access to essential health and other basic services. For persons with ID there are important disparities in access to care that are difficult to disentangle from discriminatory values and practice. Policy-makers in the United States, England and Scotland have recently begun to address these issues. It is recommended that a clear vision for health policy and strategies be created to address health disparities faced by persons with ID in Canada.