The cost and risk impacts of rerouting railroad shipments of hazardous materials

Rail shipments of hazardous materials expose the population near the routes to the possibility of an accident resulting in a spill. Rail routes are determined by economic concerns such as route length and the revenue generated for the originating carrier. In this paper we consider an alternate routing strategy that takes accident risks into account. We employ a model to quantify rail transport risk and then use a weighted combination of cost and risk and generate alternate routes. In some cases the alternate routes achieve significantly lower risk values than the practical routes at a small incremental cost. While there are generally fewer rerouting alternatives for rail than for road transport, considering the possible consequences of a train derailment we argue that risk should be taken into account when selecting rail routes and that the cost-risk tradeoffs should be evaluated.     

Applying genetic algorithm to a new location and routing model of hazardous materials

Nowadays – particularly in systems dealing with hazardous materials (HAZMAT) – in addition to minimising the cost of operations in facility location and routing problems, the risk of these operations is considered an important objective. In this paper, a new mathematical model for the location and routing in facilities and disposal sites is proposed. Also, the risk and cost of transporting goods from facilities to customers is considered. The model minimises weighted sum of the cost and risk by answering these questions: (1) where to open the facilities which produce HAZMAT; (2) where to open disposal sites; (3) to which facilities every customer should be assigned; (4) to which disposal site each facility should be assigned; (5) which route a facility should choose to serve the customers; and (6) which route a facility should choose to reach a disposal site. A novel GA is applied to solve the mathematical model. The results show the robustness of GA in terms of finding high-quality non-dominated solutions and running time.     

Computer-based environmental exposure and risk assessment methodology for hazardous materials

The Chemical Migration and Risk Assessment (CMRA) methodology consists of state-of-the-art overland and surface water models and a statistical program that analyzes the simulation results. These computer models simulate the transport and fate of both dissolved and sediment-sorbed contaminants and provide the risk assessment by predicting acute and chronic impacts to aquatic biota. The CMRA methodology was applied to the Yazoo River Basin, Mississippi, and the Wolf Creek Basin, Iowa, to assess the impact on fish of the pesticides, toxaphene and Alachlor, applied to farmland in those areas. Study results indicated that toxaphene caused both lethal and sublethal damage to four species of fish studied in the Yazoo River Basin, while Alachlor did not have a measureable impact in Wolf Creek Basin. These studies demonstrated the usefulness of this methodology as both a decision-making and research tool. Partially because of the results of the Yazoo River Basin Study, the United States banned the use of toxaphene in this country.     

The methodologies of hazardous materials transportation risk assessment

Intense interest now exists in the potential of risk assessment as an aid to public and private decision making on hazardous activities. Inadequacies in its methodologies and supporting data have nevertheless so far limited its efficacy in practice. Among attacks on the problem of improving this efficacy is a project supported by the National Science Foundation which identifies and focuses on improvements in particular areas of uncertainty in risk assessment methodologies. This paper presents some of the project's material that pertains to hazardous materials transportation. It overviews the general risk assessment problem, presents a structured review of the types of methodologies employed in estimating the contribution to risk of the different phases of a hazardous material incident, and then reviews the procedures available for the evaluation of the significance of the risks estimated, and of potential means for their mitigation. Comments are made throughout, and in the paper's conclusions, on the problems arising in these estimation and evaluation processes, and on general approaches to their resolution.     

Methodological framework for developing decision support systems (DSS) for hazardous materials emergency response operations

The production, storage, and transportation of hazardous materials are processes of vital economic importance for any advanced and technologically complex society. Although the production and distribution of hazardous materials is associated with economic development, there is a significant potential danger to the natural and social environment in the event of their accidental release, a fact that prompts for the development and implementation of methods and techniques that aim to improve hazardous materials risk management decisions. The objective of this paper is to present a unified framework for developing a Decision Support System (DSS) for supporting a vital function of risk management, namely the management of emergency response operations. The proposed framework recognizes the peculiarities of the hazardous materials decision-making environment which is characterized by: (i) multiple stakeholders, i.e., persons and organizations involved in and affected by hazardous materials risk management decisions; (ii) lack of a formal management structure for monitoring and controlling in a unified manner all Emergency Response Resources; (iii) lack of clear distinction and fragmentation of responsibilities of the actors involved in risk management operations; and (iv) dynamic/real-time decisions, i.e., risk determinants change over time. The proposed framework was used in order to develop a DSS for managing emergency response operations for large scale industrial accidents in Western Attica, Greece.     

Developing a cyberbullying conceptual framework for educators

In today's technologically enhanced and changing world, incidents of cyberbullying are increasing and it is a reality that impacts children and adults. Educators need to be able to identify cyberbullying, implement effective management strategies that align with school policies, as well as engage in pro-active programming for prevention. This article proposes a cyberbullying conceptual framework that can be used as a tool to investigate cyberbullying. The framework is grounded in the literature that was analysed using a constant comparison method for purpose of identifying current and emerging themes and indicators for each of the key elements. The paper finishes with a discussion about the application of the Cyberbullying Conceptual Framework for Educators. This conceptual framework is important to educators given it helps to deconstruct the complex concept of cyberbullying and to construct praxis approaches for identification, management and prevention of cyberbullying.     

Information support for control of hazardous materials movement

The development of a prototype hazardous materials movement information system is discussed. Especially noted are the problems encountered in developing data capture and sampling procedures. Recommendations for sampling, inference and modeling as well as for data and policy analysis are provided.     

STRRAP system—A software for hazardous materials risk assessment and safe distances calculation

This work presents a powerful computational tool (Stochastic Toxic Release Risk Assessment Package, STRRAP) useful in risk assessment and emergency planning (safe distance calculation), which allows to handle the stochastic uncertainty of atmospheric parameters, critical for risk calculation when diffusion of hazardous gases or particulate matter occur as a consequence of an emission or accidental release. In fact, the random behaviour of wind intensity, wind direction, atmospheric stability and temperature, given a time horizon, (a season or a complete year), is taken into account considering also the day or night condition.STRRAP can be used for releases or emissions from static sources (for example a stack or a fixed tank in a facility) or from transportation accidents (road, rail, maritime and pipeline transport) involving different scenarios.After a stochastic simulation based on well-known diffusion models (dense and light gases, particulate matter) is carried out, the downwind pollutant concentrations are obtained, in order to compute safe distances and/or individual and societal risks.Some study cases are analyzed to show STRRAP capabilities.     

Uncertainty in compartmental models for hazardous materials - a case study

Performing uncertainty analysis on compartmental models is the main topic of this article. Elements of the methodology developed during a joint CEC/USNRC accident consequence code uncertainty analysis are introduced. The uncertainty is quantified using structured expert judgment. Experts are queried about physically observable quantities. Many code input parameters of the accident consequence codes are not physically observable but are used to predict observable quantities. Therefore, a probabilistic inversion technique was developed which 'transfers' the uncertainty from the physically observable quantities to the code input parameters. The probabilistic inversion technique is illustrated using the compartmental model of systemic retention of Sr in the human body. The article is concluded with a discussion on capturing uncertainty via compartmental models.     

Fail-safe devices for the prevention of hazardous materials spills

Many hazardous material spills can be prevented by the use of automatic container-filling procedures to determine when maximum capacity is reached. This project assessed current fail-safe technology, conducted laboratory tests of automatic devices and monitored performance of on-site automatic level controllers.In the assessment of current technology, available data on devices used to prevent tank overflow were identified and reviewed. Fourteen types of devices were investigated to determine their potential for automatic container-filling control. Although most of the fourteen level detectors could measure for either wet or dry products, some could measure both wet and dry products. The detectors were activated by electrical, electric/pneumatic, pneumatic, or mechanical action. The fourteen types of level detector devices are pressure devices, float level controls, capacitance level detectors, conductive level measurements, thermal probes, sonic-echo level monitors, inductive-level detectors, rotating-paddle level detectors, vibration-level detectors, automatic sounding, light and sight glass measurement, radiation-level measurement, microwave-level measurement, and pressure tape.Three different types of industrial plants, each having an overfilling problem with a different material, cooperated in the field testing phase. The three level control devices tested were ultrasonic, vibrating tines, and magnetic-coupled- float types, respectively.Two of the units were activated by electricity and the third was activated pneumatically. One unit controlled dry powder, the second, a viscous liquid, and the third, an aqueous liquid. Each location required an explosion-proof system. All three units were installed without significant revisions to existing containers, and all operated well for an extended period under severe weather conditions. The proper controller configuration must be compatible with the environment and must also incorporate requisite safety features and demonstrate corrosion fouling and weather resistance.     

Developing a novel quantitative framework for business continuity planning

Today’s competitive and turbulent environment persuades every organisation to implement a business continuity management system (BCMS) for dealing with disruptive incidents such as earthquake, flood, and terrorist attacks. Within a BCMS, effective and efficient business continuity plans (BCPs) must be provided to ensure the continuity of organisation’s key products. This study develops a novel approach to select the most appropriate BCPs which can meet the business continuity key measures. First, a risk assessment process is conducted to define the disruptive incidents for which the organisation should have suitable BCPs. Then, two different possibilistic programming models including hard and soft BCP selection models are developed to determine appropriate BCPs under epistemic uncertainty of input data. These models aim to maximise the resilience level of the organisation while minimising the establishment cost of selected BCPs.? Finally, a real case study is provided whose results demonstrate the applicability and usefulness of the proposed approach.     

Sugarcane bagasse: a potential low-cost biosorbent for the removal of hazardous materials

The contamination of surface water sources by organic and inorganic pollutants is a major concern in rapidly industrializing countries, and the removal of these potentially hazardous contaminants from the aquatic environment using environmentally friendly technologies is therefore crucial. Biosorption, the passive binding of pollutants using dead biomass, can be achieved using various low-cost agro-industrial residues, which are a convenient substitute to the existing technologies for removing pollutants from aqueous solutions. This review deals with the implementation of sugarcane bagasse as a cost-effective natural biosorbent. We have extensively reviewed the status of research into sugarcane bagasse-based biosorbents in raw and modified forms and explore their efficacy in the removal of pollutants. For this purpose, we considered the bagasse modification processes, modifying agents, and the effects of different experimental variables (for example, biosorbent dosage, initial pollutant ion concentration, solution pH and temperature, contact time, and adsorbent particle size) on the adsorption process and potential. Moreover, we propose the following important goals for future research: (1) determine the adsorption potential of sugarcane bagasse at pilot and industrial scales, (2) demonstrate the efficacies of biosorption techniques for real effluents, and (3) conduct a molecular modeling study to elucidate sugarcane bagasse-associated adsorption mechanism(s).     

Hazardous materials transportation: a risk-analysis-based routing methodology

This paper introduces a new methodology based on risk analysis for the selection of the best route for the transport of a hazardous substance. In order to perform this optimisation, the network is considered as a graph composed by nodes and arcs; each arc is assigned a cost per unit vehicle travelling on it and a vehicle capacity. After short discussion about risk measures suitable for linear risk sources, the arc capacities are introduced by comparison between the societal and individual risk measures of each arc with hazardous materials transportation risk criteria; then arc costs are defined in order to take into account both transportation out-of-pocket expenses and risk-related costs. The optimisation problem can thus be formulated as a 'minimum cost flow problem', which consists of determining for a specific hazardous substance the cheapest flow distribution, honouring the arc capacities, from the origin nodes to the destination nodes. The main features of the optimisation procedure, implemented on the computer code OPTIPATH, are presented. Test results about shipments of ammonia are discussed and finally further research developments are proposed.     

Influence of soil components on adsorption-desorption of hazardous organics-development of low cost technology for reclamation of hazardous waste dumpsites

The waste disposal practices on land frequently lead to the deposition of hazardous waste at geologically/hydrogeologically unsuitable locations, resulting in surface and groundwater contamination. The movement of chemicals through soil is not only dependent on the physical, chemical and biological properties of the waste but also on the characteristics of the soil of the disposal site. In this paper the authors report their results on the influence of soil components on adsorption-desorption of certain industrially widely used hazardous organics like phenol, p-nitrophenol, 4-chloro-2-nitrophenol and 2,4-dichlorophenol on typical soils of Patancheru industrial area (Hyderabad, AP, India). The data on nature of organics, soil organic matters, clay, free iron and aluminum oxides of soils are known to influence the adsorption-desorption process are presented. There was reduction up to 67.5% (organic matter removed), 53.8% (clay removed) and 24.2% (iron and aluminum oxides removed) in the adsorption capacity of the soils when compared to untreated soils indicating the role played by these soil components in adsorption process. Desorption isotherms of soil adsorbed hazardous organics exhibited hysteresis at higher initial concentration indicating the degree of irreversibility of adsorption-desorption process. Mixed microbial cultures were developed which can degrade the hazardous organics to complete mineralisation by utilizing them as sole source of carbon and their corresponding biokinetic constants were evaluated. Preparation of dumpsites with suitable soil surface having high holding capacity for organics and their in situ biodegradation by mixing with specific microbial cultures can be exploited as a cost effective technology for reclamation of hazardous waste dumpsites.     

Developing a framework for diagnosis of shear distress in asphalt surfaces

Braking and turning by heavy vehicles can trigger shear-related distress in asphalt surfaces. The evolutionary increase in vehicle tyre pressure and wheel load will result in an increase in such surface failures in the future. Shear-related distress may result from delamination at the surface layer interface, or excessive shear creep within the asphalt surface layer itself. Both deformation and delamination distress appear visually identical at the surface. When subsequently cored, secondary (or symptomatic) debonding of the interface may result in asphalt deformation distress being misdiagnosed as a delamination failure. Regardless the mechanism, a broad range of properties may be responsible and a systematic diagnosis is required to determine the root cause. A framework for the diagnosis of shear distress in asphalt surfaces is presented. The framework contains three levels of investigation, including the location of the distress (at the surface layer interface or within the surface layer), the element within the interface/asphalt responsible and finally, the components or characteristics that resulted in a reduced shear resistance. The framework relies on the assessment of surface performance relative to comparable surfaces of adequate performance. Surface age, thermal gradient and traffic-induced shear stress states must all be comparable for a meaningful diagnosis to be made. The developed framework has been used to successfully determine the root cause of shear creep in the heavy braking zone of a runway at an Australian airport. Its application is recommended for other surface distress investigations, where the environmental and traffic factors are comparable. The framework may also be adapted to forensic investigation of other distress modes.     

Value/impact assessment for the evaluation of risk reduction: Development of a framework

A framework is developed for the evaluation of risk reduction measures using value/impact assessment. The framework includes methods to deal with such issues as uncertainty, economic discounting, and socio-political decisions which might affect the analysis. The framework is applied to the case of a nuclear reactor mitigation system.     

Mobile system for extracting spilled hazardous materials from excavated soils

A technique was evaluated for the scrubbing or cleansing of excavated soils contaminated by spilled or released hazardous substances. Laboratory tests were conducted with three separate pollutants (phenol, arsenic trioxide, and polychlorinated biphenyls [PCB's]) and two soils of significantly different character (sand/gravel/silt/clay and organic loam).The tests show that scrubbing of excavated soil on site is an efficient approach for freeing soils of certain contaminants but that the effectiveness depends on the washing fluid (water + additives) and on the soil composition and particle-size distribution. Based on the test results, a full-scale, field-use, prototype system was designed, engineered, fabricated, assembled, and briefly tested under conditions where large (?2.5 cm) objects were removed by a bar screen. The unit is now ready for field demonstrations.The system includes two major soil scrubbing components: a water-knife stripping and soaking unit of novel design for disintegrating the soil fabric (matrix) and solubilizing the contaminant from the larger particles (?2 mm) and an existing, but re-engineered, four-stage countercurrent extractor for freeing the contaminants from smaller particles (<2 mm). The processing rate of the system is 2.3 to 3.8 m₃/hr (4 to 5 yd₃/hr), though the water-knife unit (used alone) can process 11.5 to 13.5 m₃/hr (15 to 18 yd₃/hr). The complete system requires auxiliary equipment, such as the EPA-ORD physical/chemical treatment trailer, to process the wastewater for recycling; under some circumstances, provision must be made to confine and treat released gases and mists. Treatment residues consist of skimmings from froth flotation, fine particles discharged with the used washing fluids, and spent carbon. The principal limiting constraint on the treatability of soils is clay content (high weight-percent), since breaking down and efficiently treating consolidated clays is impractical or not economically attractive. Most inorganic compounds. almost all water soluble or readily oxidizable organic chemicals, and some partially miscible-in-water organics can be treated with water or water plus an additive.During limited laboratory extraction tests, phenol was very efficiently removed from both organic and inorganic soils, whereas PCB and arsenic clung more tenaciously to the soils and were released less readily into the washing fluids. The extent to which the system has practical, cost-effective utility in a particular situation cannot be determined until preliminary, bench-scale lab work has been performed and acceptable limits of residual concentrations in the washed soil are adopted. Laboratory tests show that soil scrubbing has the capability of vastly speeding up the release of chemicals from soils, a process that occurs very slowly under natural leaching conditions.Note that this system requires excavation of the soil, which can subsequently be replaced or transported to a low-grade landfill. In situ washing of contaminated soil, a process in which the contaminated area is isolated for example, by grouting, and then water-flushed with removal of the wash water at a well-point is an alternative. The overall efficiency of the soil washing system is greater than that currently being achieved by in situ methods.Based on the laboratory program, a series of steps (water-knife size reduction; soaking; countercurrent extraction; hydrocyclone separation; and waste fluid treatment for reuse) was selected as the most suitable process sequence for the prototype system. The system was constructed for the U.S. (EPA) and is now being subjected to field evaluation. However, soils rich in humus, organic detritus, and vegetative matter can present special problems in the extraction of certain hazardous substances, which may not partition between the solid and fluid phases to a practical and necessary extent.     

Component choice for managing risk in engineered systems with generalized risk/cost functions

The constrained optimization of resource allocation to minimize the probability of failure of an engineered system relies on a probabilistic risk analysis of that system, and on ‘risk/cost functions’. These functions describe, for each possible improvement of the system's robustness, the corresponding gain of reliability given the considered component or management factor to be upgraded. These improvements can include, for example, the choice of components of different robustness levels (at different costs), addition of redundancies, or changes in operating and maintenance procedures. The optimization model is generally constrained by a maximum budget, a schedule deadline, or a maximum number of qualified personnel. A key question is thus the nature of the risk/cost function linking the costs involved and the corresponding failure-risk reduction. Most of the methods proposed in the past have relied on continuous, convex risk/cost functions reflecting decreasing marginal returns. In reality, the risk/cost functions can be simple step functions (e.g. a discrete choice among possible components), discontinuous functions characterized by continuous segments between points of discontinuity (e.g. a discrete choice among components that can be of continuously increasing levels of robustness), or continuous functions (e.g. exponentially decreasing failure risk with added resources).This paper describes a general method for the optimization of the robustness of a complex engineered system in which all three risk/cost function types may be relevant. We illustrate the method with a satellite design problem. We conclude with a discussion of the complexity of the resolution of this general type of optimization problem given the number and the types of variables involved.