Problematic practice in integrated impact assessment: the role of consultants and predictive computer models in burying uncertainty

Abstract

It is well known in impact assessment that predictive model outputs will be as credible as their inputs and that model assumptions will drive outputs. What is less well known is how the practice of integrated impact assessment with its pervasive use of predictive computer models and multiple teams of consultants can influence evidence relied upon in deliberations over the impacts and benefits of major projects. This paper draws on an integrated impact assessment of a major energy infrastructure project in Australia known as Basslink to examine the epistemic implications of current practice. It will be argued that what has become standard procedure can serve to diminish the disclosure of prediction uncertainty.

Analysis of uncertainty consideration in environmental assessment: an empirical study of Canadian EA practice

“…Our findings are consistent with findings of researchers from other nations (e.g., De Jongh 1988; Tennøy, Kvaerner, and Gjerstad 2006;Duncan 2008), indicating that the information communicated in EA regarding uncertainty is often simplified and incomplete. This study also confirms previous evidence from Sweden in that the effectiveness of mitigation measures, contingency plans, and follow-up programs are presented more confidently than they should be (Wiklund 2011).…”

“…Arguably, these two approaches (categorization and specific discussion) are complimentary and together would provide more useful and comprehensive information to stakeholders and decision makers. Expressing or quantifying levels of confidence is an effective means to communicate that uncertainty exists; however, where it does exist it requires further explanation or description in terms of the nature of the uncertainty, the implications for the project or decision making, and the means to address it (Duncan 2008;Geneletti et al 2003;Tennøy, Kvaerner, and Gjerstad 2006;Walker et al 2003;Wardekker et al 2008).…”

“…It is unclear whether uncertainty was intentionally hidden in the proponent's EIS (see Wood 2008), or whether proponents or practitioners thought it was too difficult or not necessary to disclose uncertainties. It may be, according to Duncan (2008), that proponents simply have a vested interest in making their EISs appear defensible and politically palatable, resulting in practices that systematically seek to minimize uncertainty disclosure. Until there are specific requirements for uncertainty disclosure, and established standards for how to do so and for the nature and level of information required in an EIS, practice will continue to be mixed.…”

“…However, because EA is designed as a process to identify and manage future outcomes, uncertainties are unavoidable (Duncan 2008). Uncertainty in EA is due, in part, to complexities in the design and operation of large development projects (Noble and Storey 2005), and to the inherent complexity of environmental systems (Berg and Scheringer 1994) À such as the large number of potentially important components and interrelationships to be considered when assessing impacts, or time lags in their response (Jaeger 1998;Findlay and Bourdages 2000).…”

“…Uncertainty in EA is due, in part, to complexities in the design and operation of large development projects (Noble and Storey 2005), and to the inherent complexity of environmental systems (Berg and Scheringer 1994) À such as the large number of potentially important components and interrelationships to be considered when assessing impacts, or time lags in their response (Jaeger 1998;Findlay and Bourdages 2000). Since there will always be knowledge gaps and uncertainty in EA (Arts, Caldwell, and Morrison-Saunders 2001), the problem is whether and how uncertainty information is communicated and how uncertainties are addressed in EA (Tennøy, Kvaerner, and Gjerstad 2006;Duncan 2008;Leung et al 2015).…”