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Society For Risk Analysis Annual Meeting 2009

Risk Analysis: The Evolution of a Science

Session Schedule & Abstracts

* Disclaimer: All presentations represent the views of the authors, and not the organizations that support their research. Please apply the standard disclaimer that any opinions, findings, and conclusions or recommendations in abstracts, posters, and presentations at the meeting are those of the authors and do not necessarily reflect the views of any other organization or agency. Meeting attendees and authors should be aware that this disclaimer is intended to apply to all abstracts contained in this document. Authors who wish to emphasize this disclaimer should do so in their presentation or poster. In an effort to make the abstracts as concise as possible and easy for meeting participants to read, the abstracts have been formatted such that they exclude references to papers, affiliations, and/or funding sources. Authors who wish to provide attendees with this information should do so in their presentation or poster.

Common abbreviations

Symposium: Risk Management Application in the Cement Manufacturing Industry

Room: Baltimore A   3:30-5:10 PM

Chair(s): Stephen Zemba

M4-A.1  15:30  Risk-based framework and applications for portland cement manufacturing. Behan F*; US GOVERNMENT

Abstract: Section 112 of the Clean Air Act establishes a two-stage regulatory process to address emissions of hazardous air pollutants, or air toxics, from stationary sources. In the first stage, section 112(d)(1) requires the U.S. Environmental Protection Agency (EPA) to develop technology-based standards to control emissions of air toxics for 174 categories of industrial sources. Portland Cement Manufacturing is one of these categories. EPA has largely completed the initial standards as required under this provision. Under section 112(d)(6), EPA must review each of these technology-based standards at least every eight years and revise a standard, as necessary, taking into account developments in practices, processes, and control technologies. In the second stage, EPA is required under section 112(f)(2) to assess the health and environmental risks that remain after sources come into compliance with the standards. If additional risk reductions are necessary to protect public health with an ample margin of safety or to prevent adverse environmental effects, EPA must develop standards to address these remaining risks. This second stage of the regulatory process is known as the residual risk stage. For each source category for which EPA issued standards, the residual risk stage must be completed within eight years of promulgation of the initial technology-based standard. This presentation will discuss the regulatory framework for the Portland Cement Manufacturing category, with a focus on those cement kilns that burn or process hazardous waste, and its interplay with risk assessment. The speaker will also discuss the use of site-specific risk assessments at hazardous waste cement kilns under the Resource Conservation and Recovery Act, the law describes the waste management program established by U.S. Congress.

M4-A.2  15:50  Realities and Conservatisms in Multi-Pathway Risk Assessments. Linkov I, Ames M, Bennett E*, Palma J; IL - USACE-ERDC-EL, Concord, MA; MA - Cambridge Environmental, Cambridge MA; EB - Bioengineering Group, Salem MA; JP - University of Lisbon, Lisbon, Portugal

Abstract: Multi-pathway risk assessments (MPRAs) are increasingly being applied to evaluate potential health risks associated with air pollutant emissions from industrial sources such as cement kilns. In the case of human health MPRAs, potential exposure to pollutants starts with the direct inhalation of the compounds while they are present in air, followed by indirect pathways whereby compounds deposit to the ground, become incorporated within soils and foodstuffs, and then consumed. Ecological MPRAs are similar, though relevant exposure endpoints include flora and fauna present in essentially all environmental compartments. Use of multiple linked models introduces considerable levels of uncertainty into MPRAs, both in terms of the adequacy of model formulations and the difficulties in estimating model parameters. This has important implications with respect to risk management, as statements are sometimes made about the tremendous level of conservativism embodied in risk estimates, but with little (if any) ability to quantify the degree of protectiveness in MPRAs that are often promoted as scientific studies. Case studies of two detailed MPRAs will be examined to investigate the sensitivity of risk estimates to various types and compounding of biases. The first MPRA focuses on potential exposure to mercury due to emissions from a cement kiln in the Midwestern United States. The second MPRA examines potential risks to citizens living in communities near a cement manufacturing facility in Portugal. In each case, the scenarios considered in the MPRA will be used to illustrate the difference between worst-case regulatory risk and best-estimate risk through comparison of (1) permit-based emission rates vs. measured emission rates, (2) consideration of actual operating conditions, and (3) location–specific considerations that affect the transposition of exposure pathways and modeled facility impacts.

M4-A.3  16:10  Risk Assessment of Hazardous Air Pollutants from Cement Kilns: Case Study of a Facility with Extensive Emission Data. Zemba S*, Ames M, Bennett E, Palma J; Cambridge Environmental Inc., 58 Charles St., Cambridge, MA 02141

Abstract: Stack emissions from Portland cement manufacturing facilities contain a variety of air pollutants. Multi-pathway risk assessment (MPRA) has evolved as a tool for assessing potential human health and ecological risks to persistent, bioaccumulative Hazardous Air Pollutants (HAPs) such as mercury and dioxin. MPRA simulates the dispersion, transport, and fate of HAPs as they deposit from air into foodwebs. A key uncertainty in MPRAs has been the confidence in HAP emission estimates, as typical analyses of long-term health risks are often based on stack tests of a few hours duration. Variability in limited test runs, as well as uncertainties in methods and temporal representativeness of test conditions, lends considerable overall uncertainty in the overarching emission estimates that drive the MPRA. Moreover, cement kilns often utilize alternative fuels, including hazardous wastes. he effect of co-firing various combinations of fuels adds another source of uncertainty, and sometimes concern among stakeholders. This presentation will focus on HAP emission variability and uncertainty using an extensive set of stack measurements at the SECIL Outão (Portugal) facility. Analysis of a rich and informative database will examine relevant and interesting aspects of facility emissions, and will include basic statistics and time trends, as well as comparisons of firing standard fuel and various special alternative fuels (both hazardous and non-hazardous). We have noted in our review thus far that, for many contaminants, emissions during special fuel use are lower. Comparisons with applicable emission standards and the performance of other cement kilns will also be provided to evaluate the efficacy of advanced air pollution measures in place at the SECIL Outão facility. Results ill be used to evaluate the adequacy of typical measures of handling emission uncertainty in MPRAs (such as the selection of maximum emission rates from limited data sets).

M4-A.4  16:30  Risk perception and participatory processes: that case of Secil – Outão cement facility. Palma-Oliveira J.*, Marques N., Antunes D., Maia N.; University of Lisbon

Abstract: It is a given fact that industries have been improving dramatically its environmental and social performance in the last decades. However even in the case where that improvement is objective and measurable, that fact is seldom recognized by the nearby communities. This lack of recognition is received with a certain amount of resentment by the industry that expects always a negative reaction whatever their behaviour might be. We considered that this is a process with a psychosocial root that can be understood and that is possible to derive a strategy to overcome that negative situation. Trough a risk communication strategy that includes work in the trust factors (stakeholders committee, open plant, etc.) very positive results were achieved, such as lowering the risk perception and improving the attitude towards the plant. The results were assessed with a regular psychosocial monitoring program (that began in 1997) that measures these variables among others. This paper describes how the psychosocial monitorization assesses the risk communication strategy and how the risk perception results can be used as an indicator of sucess of the risk communication strategy.

M4-A.5  16:50  A Multi-Pathway Human Health Risk Assessment of Stack and Fugitive Emissions from a Cement Manufacturing Facility Encompassing Current and Proposed Future (Expanded) Operations. Haack E*, Treissman D, Baulk E, Rhydderch D, Ramesh G, Auger A, Watson B; WorleyParsons Infrastructure and Environment, Calgary, AB, Canada (1-5); Lafarge Canada Inc., Exshaw, AB, Canada (6-7)

Abstract: Multiple conservative factors are built into risk assessment for reasons including, but not limited to: calculation of worst-case estimates of risk; derivation of exposure limits (safe dose); protection of the most sensitive receptor; accommodation of unknowns/data gaps; and, regulatory requirements. In this manner, a risk assessor can be confident that results below the acceptable level of risk indicate no adverse health effects. However, it also means that results exceeding the acceptable level of risk may either indicate potential adverse health effects, or may be an artefact of the multiple conservative assumptions built into the risk assessment methodology. How does one then interpret and communicate risk results close to the acceptable risk thresholds and effectively communicate conclusions of no potential risk when results exceed acceptable thresholds? This case study will discuss how these conservative assumptions were communicated to stakeholders (employees, regulators, local residents, local environmental organizations and media). Multiple receptor locations, chemicals, emission scenarios, and exposure pathways were assessed. Additional incremental risk analysis of PM2.5 was conducted using Health Canada SUM15 methodology. Some of the risk results were higher than the acceptable threshold of risk. In order to communicate the level of potential risk associated with these scenarios, each was thoroughly investigated; each input value and conservative assumption was examined. It was determined these results did not indicate a potential health risk to persons living in the area. Methods, results, conservative assumptions and recommendations of the complete risk assessment were distributed in a detailed written report and presented at interactive public meetings. Effective, communication, transparent methodology and attention to all stakeholder issues were critical to obtaining project approval.

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