Making sense of significance in environmental impact assessment

Abstract

Impact significance determination lies at the heart of environmental impact assessment (EIA) but conflict and misunderstanding around the concept is common. This paper attempts to make sense of impact significance in EIA based on four essential components of significance synthesised from the literature to ensure that: (1) a clear operational framework for significance determination applies throughout EIA, (2) attention focuses only on significant issues, (3) the term significance is specified and applied consistently, and (4) significance determinations are transparent to all EIA stakeholders. To provide a practical perspective, the extent to which EIA institutional provisions in Western Australia uphold these significance determination components is reviewed. Overall the Western Australian approach generally meets all four components, but areas for improvement include better guidance encouraging proponents to adopt a more consultative approach to determining relevant environmental factors and objectives to better focus EIA, and distinguishing between terms used for significance within EIA documentation. A new significance framework approach in Western Australia represents a clear attempt to uplift practice, but opportunity exists to improve the way impact significance determinations are presented to stakeholders. EIA practitioners may benefit from mapping and making sense of impact significance in their own jurisdiction using the four components presented.

Keywords:

• Significance determination
• EIA
• decision-making
• transparency
• Western Australia

1. Introduction

Since its beginnings in the 1970s, environmental impact assessment (EIA) has been concerned with focusing on key impacts (Kennedy and Ross 1992). This places the concept of significance at the centre of each decision-making phase of the EIA process (Sippe 1999; Ross et al. 2006).

In the absence of a legal definition for the concept, how significance is treated by different jurisdictions notably differs (e.g. Duinker & Beanlands 1986; Canter & Canty 1993; Sippe 1999). However, common elements and recurring themes are evident within EIA significance discussions. For example, in calculating impact significance, there is a need to consider impact characteristics on the one hand and also impact importance (e.g. Kjellerup 1999; Sippe 1999), which Sadler and McCabe (2002) combine into an impact significance equation (Figure 1).

Figure 1. Impact significance equation. Source: Sadler and McCabe (2002, p. 274).

Other commonalities of impact significance are that it requires judgements to be made within a political context, involving consideration of the amount of change to the environment perceived to be acceptable to the community including cumulative impacts (e.g. Sippe 1999; Gibson et al. 2005).

With the result of an EIA dependent on the determination of significance, it becomes of critical importance to the EIA process (Briggs & Hudson 2013). However, it remains a misunderstood component of the EIA process and a cause of conflict with the meaning of significance varying throughout the various phases of the EIA process (Kjellerup 1999; Lawrence 2007; Wood 2008).

In this paper, we attempt to make sense of impact significance in EIA by firstly distilling the essential components of impact significance from the literature, and secondly critically reviewing the extent to which EIA institutional provisions in Western Australia conform to each component.

2. Essential components of significance determination

The use of significance in hundreds of EIA systems internationally has seen it evolve to meet the specific requirements of each jurisdiction (Sippe 1999). Although numerous procedures, criteria and methods are described within EIA literature, no consensus has been reached on the most effective method/s to determine impact significance (Lawrence 2007). However, Lawrence (2007, p. 762) notes that most approaches are phased or iterative with the common realisation that:

•	not all potential impacts can be considered;
•	not all impacts should be considered to the same level of detail; and
•	impacts vary in their decision-making importance.

Based on a literature review, we propose there are four essential components to determine significance that warrant simultaneous consideration during EIA:

(1)	Have a clear operational framework for how significance is determined throughout the EIA (Kennedy & Ross 1992; Canter & Canty 1993; Sippe 1999; Wood 2003, 2008; Ross et al. 2006; Lawrence 2007; Ehrlich & Ross 2015);
(2)	Focus EIA attention only on significant issues (Ross et al. 2006; Briggs & Hudson 2013; Wood 2003; Sadler & McCabe 2002; Morrison-Saunders & Bailey 2000; Kennedy & Ross 1992; IAIA & IEA 1999; Sippe 1999; Canter & Canty 1993; Duniker and Beanlands 1986);
(3)	Ensure that the term significance is specified and applied consistently (Ross et al. 2006; Ehrlich & Ross 2015); and
(4)	Uphold transparency in decision-making so that significance determinations are clear to all EIA stakeholders (International Association for Impact Assessment & Institute for Environmental Assessment 1999; Morrison-Saunders & Bailey 2000; Gibson et al. 2005).

We briefly discuss each of these in the sections that follow.

2.1. A clear operational framework for how significance is determined throughout the EIA

Ehrlich and Ross (2015) provide an extensive review of impact significance literature leading to their own clear operational framework for determining significance in EIA practice. This is the most advanced and detailed account for significance determination during EIA decision-making in the literature. Ehrlich and Ross (2015) refer to the ‘significance spectrum’ and employ a four-step process to demonstrate how significance determinations should be made:

•	Determining the threshold for significance for each valued component;
•	Weighing the evidence and considering predicted impacts;
•	Deciding which side of the threshold the predicted adverse impacts fall on; and
•	For unacceptable impacts, deciding if mitigation measures can make the residual impact acceptable.

Central here is the development and use of thresholds, criteria and standards for measuring and judging significance as noted by earlier commentators (e.g. Duinker & Beanlands 1986; Sippe 1999; Wood 2003). It includes the consideration of three broad levels of significance corresponding to impacts that are: (1) significant and not mitigable, (2) significant but mitigable and (3) insignificant (Canter & Canty 1993). Sippe (1999) discussed significance in the context of acceptability of predicted residual impacts, which is realised during the fourth step of the Ehrlich and Ross (2015) framework. It is not our intention to further duplicate the work of Ehrlich and Ross (2015) here. The key point we wish to make is that given the centrality of significance determination to the practice of EIA, it is essential to have in place a robust operational framework such as this. It seems that without such thinking and procedures in place, EIA decision-making will get bogged down and lead to poor or poorly implemented decisions.

2.2. Focus on significant issues only

A basic principle of EIA is it should be focused and concentrate on the identification of significant impacts (International Association for Impact Assessment & Institute for Environmental Assessment 1999). Scoping should establish what is of significance to decision-makers while eliminating matters of insignificance (Kennedy & Ross 1992). Similar views are common in the EIA literature: for example that resources be concentrated on impacts of importance to the project and public (Duinker & Beanlands 1986), assessment of only those factors likely to have a significant impact (Wood 2003), and that effective scoping requires priorities to be set with the onus on the decision-maker to disregard insignificant issues before detailed investigations are initiated (Ross et al. 2006).

Despite consensus on the need for EIA to focus only on significant impacts, scoping efforts rarely seem to meet this need. Ross et al. (2006) noted a propensity among consultants, published guidance and terms of reference to direct proponents to cover all and any possible impacts regardless of their relevance in shaping the final outcome. They suggested that the problem stemmed from regulator failure to make a decision on what issues should be addressed through the EIA process. Snell and Cowell (2006) similarly found practitioners were inclined to include all possible impacts with EIA documents, not as a result of environmental precaution, but for fear of future legal challenges. Noble and Birk (2011) noticed this tendency to continue during project implementation, coining the term ‘comfort monitoring’ for monitoring carried out in the interests of providing ‘peace of mind’ (p. 23) rather than contributing useful data for effects-based management.

Clear from these examples is the need to focus EIA attention onto significant issues as an essential component of significance determination.

2.3. The term significance is specified and applied consistently

With the primary focus of EIA to communicate the significance of potential impacts associated with a proposal to numerous stakeholders (Wood 2008), the term significance should be specified and applied consistently throughout the process by both proponents and decision-makers. In advocating for common sense to be applied in EIA, Ross et al. (2006) emphasise the necessity for ‘careful distinction in the use of the term significance’ (p. 7). Aside from the traditional meaning of the term significance i.e. ‘importance for decision-makers’ (p. 5), they noted it was also used to denote the perception of significance, as well as certain technical or specialised aspects such as statistical significance or ecological significance. They also observed interchangeable use of the term significance in EIA documents and suggested that lack of distinction in the terminology resulted in confusion. Other authors similarly advocate for the term significance to be specified and applied consistently, for example: 


•	Kjellerup (1999) found use of the term significance within the Danish EIA system on an individual project basis was unclear with failure to distinguish between the different terms in the correct context resulting in obvious biased decisions towards approval.
•	Au (2006) identified numerous cases in Hong Kong of what proponents held to be insignificant impacts later being considered significant by other stakeholders.
•	Wood (2008) criticises the extensive and inconsistent use of the term significance within legislation, guidelines and statements in the UK; noting the EIA process is susceptible to bias when inconsistent language is used especially in favour of proponents who have substantial control over the information upon which decisions are based.
•	Ehrlich and Ross (2015) noted that interchangeable use of significance-related terminology resulted in additional time spent by decision-makers identifying and communicating to proponents the errors in terminology and subsequent conclusions reached.

While we do not expect a universal definition to emerge on how significance should be expressed, within the context of a given EIA jurisdiction it is highly desirable that consistent terminology is specified and employed.

2.4. Transparency in decision-making and significance determinations

Transparency in decision-making includes recognition that well-defined aims and objectives through a clear and open process are essential for successful EIA (e.g. International Association for Impact Assessment & Institute for Environmental Assessment 1999). Lawrence (2007) noted the importance of clearly identifying the connections between significance determination and decision-making, particularly in relation to how these determinations form and guide the EIA process. Wood (2008) found transparency could be enhanced through the use of well-defined significance criteria and evaluation frameworks. Briggs and Hudson (2013) encountered difficulties in comparing projects in part due to a lack of transparency of numerous factors required to determine significance. Finally, Ehrlich and Ross (2015) note that to guarantee transparency in their ‘significance spectrum’, justification of the rationale and decisions made during significance determination must be stated in language that is accessible to all EIA stakeholders. In short, all EIA stakeholders should be able to understand the relationship between significance determination and decision outcomes.

We now illustrate how these four components for making sense of significance in EIA play out in practice, using the Western Australia process as an illustrative example.

3. Significance in Western Australia EIA institutional arrangements

The EIA process in WA was recently explained in Dahlitz and Morrison-Saunders (2015). The Environmental Protection Authority (EPA) is established under the Environmental Protection Act 1986 (EP Act) with provisions for EIA of project level proposals ‘likely, if implemented, to have a significant effect on the environment’ (s37B(1) of EP Act). The Act sets out the necessary basic elements of EIA, with Administrative Procedures developed by the EPA (under s122 of EP Act) detailing the procedures to be followed – the current version being Government Gazette (2012). We illustrate how these institutional arrangements address significance determination in relation to the four essential components outlined previously.

3.1. A clear operational framework for how significance is determined throughout the EIA

What the EPA considers significant are known locally as ‘key environmental factors’ (s44 of EP Act) and for each of these the EPA has set a generic objective that proponents are expected to meet during EIA (Dahlitz & Morrison-Saunders 2015). Proponents are expected to ‘identify environmental factors likely to be impacted and the aspects likely to cause impacts’ as a result of the proposed development (Government Gazette 2012; s5). This occurs via the development of an environmental scoping document early in the EIA process. The objective of the scoping document is to identify preliminary key environmental factors specific to the proposal and to determine studies and investigations required to be undertaken by the proponent in relation to the identified environmental factors (Government Gazette 2012, s10.2.3).

The EPA’s framework for environmental principles, environmental factors, objectives and guidance forms the foundation of decision-making on the ‘environmental acceptability’ of proposals (EPA 2015a; p. 2). In determining acceptability, the EPA applies ‘professional judgement’ to decide if a proposal is likely to have a significant effect on the environment (Government Gazette 2012; s7 p. 5943). In Western Australian EIA, significance in decision-making has long been considered via the use of a decision tree developed by Sippe (1999) with a test of acceptability tied to mitigation which may be required to be included in approval conditions in order make a proposal acceptable. The EPA (2015b) recently published a Significance Framework (Figure 2), which is similar in design and application to the significance spectrum of Ehrlich and Ross (2015).

Figure 2. EPA significance framework. Source: EPA (2015b).

How significant the impacts of a proposal are depends on whether or not the EPA’s environmental objectives for the identified environmental factors can be met (Environmental EPA 2015b). For a proposal to be ‘environmentally acceptable’, the proponent is obligated to demonstrate how the ‘unavoidable impacts’ will meet the EPA objectives for the identified environmental factors (Government Gazette 2012; s5.4). The EPA (2015a) considers this focused approach to the assessment to represent EIA best practice. As with Ehrlich and Ross (2015), mitigation measures and proposal modifications can be applied to help shift the expected outcome from one category to a more acceptable position.

The EPA’s Significance Framework satisfies our first component of providing a clear operational framework for how significance is determined throughout EIA. It is available to all stakeholders for reference and application. Proponents know what to focus their efforts on after the scoping stage, and how their proposals will be evaluated by the EPA, while the recommendations to the Minister provide the public with information on the significant issues and associated conditions.

3.2. Focus on determining the significant issues only

The EPA’s approach to EIA includes extensive guidance materials being made freely available to proponents. The guidance on environmental principles, environmental factors and objectives mentioned previously (EPA 2015a) outlines the expectations for proponents to identify environmental factors via the development of a scoping document aimed at focusing the assessment on factors most likely to be significant (Government Gazette 2012; EPA 2015b).

The notion of ‘public concern’ that appears in s38(4) of the EP Act as the basis for the Environment Minister to direct the EPA to undertake an assessment is another term used to denote significance. Similarly, a professional judgement criteria employed by the EPA as part of their ‘significance test’ is ‘public concern about the likely effect of the proposal, if implemented, on the environment’ (Government Gazette 2012, s7). What remains unclear is how the notion of public concern intercepts with key environmental factors. This could potentially result in the assessment of projects where no specific significant environmental factors feature.

Dahlitz and Morrison-Saunders (2015) describe the value of utilising factors and objectives as providing ‘clear focus, structure and communication’ (p. 146). This assists in determining significant issues and contributes to decision-making throughout the EIA. However, as a fundamentally subjective exercise this ‘risks being reductionist’ as prescriptive guidance material directs proposals to be compartmentalised into environmental factors that can be described in objective terms, excluding those more subjective characteristics that together form the environment (Dahlitz & Morrison-Saunders 2015, p;.146). To mitigate this risk, Dahlitz and Morrison-Saunders (2015) recommend a more consultative approach to the use of factors and objectives rather than continued reliance on regulator guidance only. In the context of cumulative effects, it is possible for overall levels of public concern regarding a proposal to be high, even where individual factors are individually considered to be acceptable by the EPA.

The provision of guidance material on key environment factors developed by the EPA generally satisfies our second essential component of focusing EIA on significant issues only. However, there is room for improvement via adoption of a more consultative approach to identify factors and objectives and clarifying what ‘public concern’ might constitute.

3.3. The term significance is specified and applied consistently

The EPA considers the intrinsic characteristics and the importance attached to the receptors of the impact for each key environmental factor through the application of ‘significance test’ criteria (Government Gazette 2012; s7). Similar in design and application to the impact significance equation (Figure 1), it implies a consistent approach to impact significance determination, albeit one based on professional judgement. We previously noted different terminology employed within the significance test criterion pertaining to ‘public concern’ relative to the notion of key environmental factors. Other terminology denoting or implying relative significance of particular matters is also evident in the assessment reports of the EPA, especially around ecological considerations and to be fair here many of these terms originate in other legislation or guidelines. Nevertheless, potential for confusion does exist as illustrated in Box 1. We maintain that it must be possible and appropriate to utilise significance related terminology with greater specificity and consistency than this.

Box 1. ‘Significance’ related terms used by the EPA (2011) when assessing a shipping port proposal on a greenfield site.

Table

• Declared Rare Flora (p. 11) • priority species (p. 11) • priority flora (p. 11, 12) • determination of conservation significance of proposed impacts to priority flora species (p. 13) • investigations into the regional significance of sub-association 2 [vegetation community] (p. 13) • extent of indirect impacts to significant flora and vegetation communities (p. 14) • protect the environmental values of areas identified as having significant environmental attributes (p. 14) • endangered vegetation (p. 15) • being at the ‘threshold level’ (p. 15) • affect the conservation significance of these associations (p. 15) • priority 1 species (p. 15) • conservation significant species (p. 16) • listed species of conservation significance (p. 16) • Specially Protected (Threatened) and Priority Fauna and their habitats (p.19) • Low and High Ecological Protection Areas (p. 22) • significant industry buffer (p. 26) • a significant portion has been designated as industry buffer (p. 26)

Finally, in Section 37B of the EP Act, the term significant is used in the definition of ‘significant proposal’ i.e. ‘significant proposal means a proposal likely, if implemented, to have a significant effect on the environment’. Reference is then made back to this definition in both the Administrative Procedures (Government Gazette 2012) and in EPA (2015a). Although there is consistency in reference to the term significance here, it is unclear as to what specific terminology should be applied in each instance i.e. what is important to decision-makers, the perception of significance or technical/specialised aspects.

As with the case internationally noted previously, in Western Australia onus is placed on proponents to define significant impacts with the assumption that they will also apply the term ‘significant’ consistently throughout their EIA documentation. Currently, no specific guidance material is provided to proponents regarding this, meaning that potentially biased information could be produced that the EPA then relies on as part of their own assessment process. This is an area that could be improved upon. For example, the Administrative Procedures allow the EPA to provide additional guidance on what is significant (Government Gazette 2012, s.8.1), this could be a basis for providing clarification for the benefit of all EIA stakeholders.

3.4. Transparency in decision-making

The EPA’s Significance Framework and other guidance material represent a clear attempt to provide transparency throughout the EIA process. For example, after the scoping stage those issues not considered to be significant (i.e. not to be key environmental factors) no longer receive deliberation by the EPA and the proponent is not expected to spend time and resources studying these (EPA 2015b). The EPA also liaises with proponents when setting the conditions for recommendation to the Minister (Government Gazette 2012; s16), resulting in no surprises in ongoing requirements of the proponent. It is reasonably simple for stakeholders to understand to what degree environmental factors are taken into account by decision-makers and if/how projects are amended as a result of this process including the treatment of public submissions (Morrison-Saunders & Bailey 2000).

Overall, the transparency component of significance determination is satisfied by the Western Australian EIA arrangements. As specified in the EP Act (s48B), the EPA is required to ‘keep a public record of each scheme referred to it’ and each record must be ‘made available for public inspection’. In practice, all EIA project and process information is made publically available on the EPA website.

However, McHenry et al. (2015) maintain that simply publishing project documentation is not the same as providing full transparency. In the context of mine closure planning, they argue that full transparency requires that all reasonably educated interested or affected individuals are able to access, comprehend and form a big picture of a project including financial implications and environmental and social consequences using the published project documentation. They illustrate using Western Australian mining case studies (that had undergone EIA) that despite project documentation being made available to the public, the volume, size and multiple locations where information can be obtained represents a challenge to understanding the project and the effects. As with our previous suggestion that there is potential to enhance the language and communication around significance determination, so too clear and transparent disclosure of how significance determinations influence EIA outcomes in Western Australia could be enhanced. The significance framework (i.e. a relatively new approach) is an important step in this direction but we suggest that there is room for further improvement regarding the way project documentation and significance determination is made available to all EIA stakeholders.

4. Conclusions

In this paper, we attempted to make sense of impact significance in EIA by identifying four essential components drawn from EIA literature; to: (1) have a clear operational framework for how significance is determined throughout the EIA, (2) focus EIA attention only on significant issues, (3) ensure that the term significance is specified and applied consistently and (4) uphold transparency in decision-making so that significance determinations are clear to all EIA stakeholders. We then critically reviewed the extent to which EIA institutional provisions in Western Australia conform.

Generally, the Western Australian EIA arrangements satisfy the four impact significance components. However, we suggest the most effective way to improve compliance with the four components is for the EPA to develop further guidance:

•	encouraging proponents to apply a more consultative approach to factors and objectives to provide focus to EIA; and
•	distinguishing terms to be used for significance in EIA documentation, including example scenarios of common misuses to avoid.

Similar to the recent example put forward by Ehrlich and Ross (2015), EPA’s Significance Framework represents a clear attempt to provide transparency and rigour in impact significance determinations in EIA. We suggest there is room for improvement in the way project documentation and impact significance determinations are made available to stakeholders. We hope that other EIA practitioners will benefit from reflection upon the four components of impact significance determination in the context of their own jurisdictions and the example from Western Australian practice we have provided here.