Chapter 8 Significance Determination

Question 1

fact of an environmental impact

Answer 1

The change itself, its magnitude, direction, units, and the estimated probability that it will occur.

Question 2

The meaning of an environmental impact

Answer 2

the value placed on the change by different affected interests

Question 3

Impact significance

Answer 3

The degree of importance of an impact based on the characteristics of the impact, the receiving environment, and societal values.

Question 4

What is considered a significant impact is __________________, _________________, ________________, and _______________. there will always be many issues to take into consideration.

Answer 4

dynamic, contextual, political, and uncertain.

Question 5

there will always be regulatory, social, political, and site-specific issues to take into consideration, and what is considered significant in one context may ______________________.

Answer 5

not be so in the next

Question 6

Provide an example on fish population

Answer 6

Consider a mining project that will involve the discharge of effluent to a lake system, leading to a decline in fish population. Is the effect of the mining operation on the lake system a significant adverse effect? It might depend on the magnitude of the effect (i.e., how much will the population decline?) or the duration and reversibility of the effect (i.e., how long will it last, and can it be corrected?), but it also depends on context (i.e., whether the lake is a highly valued source of traditional foods or whether the fish is a rare, threatened, or protected species).

Question 7

Determinations of impact significance begin at the _________of the EA process when a decision is made as to whether __________________________________________________________________________________________________.

Answer 7

outset; the proposal requires a formal assessment and extends throughout the scoping, prediction, mitigation, and follow-up stages.

Question 8

The dominant focus of significance determination in EA, however, is on the significance of potential ____________________.

Answer 8

residual effects

Question 9

residual effects

Answer 9

the effects that remain after proposed mitigation measures are taken into consideration.

Effects that remain after all management and mitigation measures have been implemented.

Question 10

Table 8.1 Interpretations of Significance in the EA Process

Answer 10

pg. 147

Question 11

Is there an official definition for “significant” impact in EA?

Answer 11

NO

Question 12

What factors does the Canadian federal Impact Assessment Act consider for significant impacts?

Answer 12

Indigenous and local knowledge, public input, and the feasibility of mitigation measures

Question 13

basic principles and concepts that characterize significance and are more or less accepted among the community of EA scholars and practitioners:

Answer 13

• Significance determination is not solely a scientific exercise.
• What is significant is subjective and varies based on the values and perceptions of different stakeholders.
• What is significant in one context or at one place and time may not be so at another.
• Significance determinations are made based on incomplete information and under uncertain conditions.
• There is no standard method for significance determination that will work for all projects or for all impacts.
• A determination of a significant adverse impact does not mean that a project should be rejected, but if the project is approved, then the impacts must be justified.
• Significance determinations and the justification of projects with significant adverse impacts must be transparent.

Question 14

impact measurement

Answer 14

In the context of significance determination, the characteristics of the impact (e.g., magnitude, spatial extent, duration).

Question 15

impact meaning

Answer 15

In the context of significance determination, the context within which impact characteristics are viewed and interpreted (e.g., regulatory, social, ecological, sustainability).

Question 16

Impacts are ultimately measured on the yardstick of _______________, and any comprehensive definition of a significant impact in EA must reflect this ________________ . As Ehrlich and Ross (2015) explain, subjective judgment, informed by a body of evidence and reflective of societal values, is not only credible but a mainstay of some of the most important decisions made in society; the same principles lie at the heart of significance determinations.

Answer 16

human values;
value judgment;

Question 17

Give examples of impact meaning and measurement:

Answer 17

page 149

Question 18

“significant” is defined as an adverse effect that could occur as a result of what?

Answer 18

its magnitude, geographic extent, duration, frequency, reversibility, or probability of occurrence

Question 19

when relying upon a single language or term in the final assessment of significance, variance in meaning and interpretation remain deeply entrenched. This results in an impact significance determination that is not only ___________________________ but one that is __________________________________________________________________________________________________

Answer 19

open to multiple interpretations;

inherently simplistic and with no benchmarking to the project’s context or environmental setting or the expert assessor’s professional frame of reference

Question 20

The complexity of significance is exacerbated by context, comprising issues of social and cultural values, ecological sensitivity, economic goals, and institutional and political interests. Baker and Rapaport (2005) suggest that the evaluation of significance based strictly on scientific data (e.g., species populations, habitat metrics, emissions levels) is _________________________________________________.

Answer 20

inadequate in many cases because technical and quantitative approaches often do not capture issues of social or cultural significance.

Question 21

In our experience, we have observed that technical experts are usually engaged in analyzing impact characteristics such as impact geographic extent, magnitude, etc. (typically described as the technical bases for significance determinations). For example, a biologist may predict that a valued component may be affected to a certain degree, over a certain area, over a certain time, with a certain probability. We suspect, however, that if you were to ask that biologist the crucial question of whether or not the predicted change is acceptable, the biologist should respond that ____________________________________________.

Answer 21

the answer is not a strictly scientific judgement.

Question 22

Haug et al. (1984), however, do suggest a priority in the types of criteria used to provide context for significance determination—namely, the following:

Answer 22

legal context (e.g., laws, regulations), functional context (e.g., science, ecological limits), and normative context (e.g., social values, acceptable levels).

Question 23

Legal or regulatory designations or standards

Answer 23

Predicted effects or impacts following mitigation are often compared against environmental standards or regulations—in essence, specified thresholds. The use of standards and regulations is the most common and arguably robust, context-based criterion in significance determination.

Impacts within specified standards or that do not exceed certain regulatory limits are deemed to be insignificant in comparison to impacts that do exceed standards or limits.

ex. water quality guidelines to protect aquatic life, critical habitat thresholds for caribou.

Question 24

There are three types of standards or regulatory limits typically used for significance determinations:

Answer 24

• Exclusionary – leads to automatic rejection of a proposal
• Mandatory – leads to a mandatory finding of significance
• Probable – normally significant but subject to confirmation

Question 25

An impact should always be identified as significant if it _____________________________.

Answer 25

Exceeds a government-determined limit or does not meet a specified regulatory standard

Question 26

There is a tendency for some proponents and EA practitioners to compare the relative impact of a project to the impacts of other activities as a basis for significance determination. If a project’s impacts are small compared to the impacts of other activities, a case is then presented that the project’s impacts are not significant. Is this a good practice or bad?

Answer 26

Bad

Question 27

Rather than assess the significance of a project’s impact relative to the impacts of others, impacts should be assessed relative to ______________________________________________.

Answer 27

defined benchmarks or limits.

Question 28

Debunking the “Compared-to” Approach for Significance Determination

Answer 28

The EA of the Ajax mine project, a proposed open-pit copper and gold mine in British Columbia, estimated that the project’s annual GHG emissions would constitute only 0.048 per cent of the province’s annual emissions and 0.016 per cent of Canada’s annual emissions. The EA concluded that the project’s effects on GHG emissions were therefore negligible and overall not significant. Although a common practice used in EA to justify a project’s impacts, this “compared-to” argument is a misrepresentation of the significance of a project’s impacts and holds little merit. Joseph (2019), in a letter to Impact Assessment and Project Appraisal journal, turns the tables on the “compared-to” argument. Using climate change and the Ajax mine as the example, Joseph explains that for adverse impacts, proponents will often compare the magnitude of their project’s GHG emissions to the emissions of other projects or to the emissions of an entire sector or state and then present the case that the project’s impacts are thus insignificant. Joseph presents a counter-scenario, arguing that a project proponent would never use the same flawed logic to assess and communicate a project’s positive impacts. Employment opportunities created by the project, for example, or the project’s contribution to gross domestic product, are often presented as “significant” positive impacts based on project-specific values alone—without comparison to the resource sector or state at large. However, if one adopted the same reasoning used for characterizing adverse impacts, then the contribution of a single project to employment or gross domestic product would likely be highly “insignificant” compared to the entire resource sector. Joseph describes this approach as “faulty logic.”

Question 29

Limits also need to be consistent with those monitored by the scientific community (Dubé et al., 2013). One approach is to benchmark project-induced change against what?

Answer 29

the range of natural variability (RNV) for the affected environmental component

Question 30

range of natural variability (RNV)

Answer 30

refers to the spectrum of natural conditions possible in ecosystem structure, composition, and function when considering both temporal and spatial scales

In other words, it is the spectrum of states and processes encountered in an ecological system (e.g., habitat condition, species population) over a long period of time (Gayton, 2001). Deviations close to, or outside of, the RNV caused by development actions may be considered significant adverse impacts.

Question 31

Most definitions of ecological limits still require the use of ______________________________ against which to interpret the severity of the impact

Answer 31

A non-ecological standard

Question 32

To assert that the impact, which may indeed be ecologically insignificant, is therefore not significant …..

while ecological significance must play an important role in determining the significance of an impact, it must not be the only determinant, since societal values play an important role in determining what is significant in the overall assessment of a project.

Answer 32

may not be an acceptable conclusion because it excludes the societal values that a local human population may place on the species.

Question 33

Figure on Vulnerability and irreplaceability as context for significance determination

Answer 33

8.3 pg 155

Question 34

statistical significance

Answer 34

In statistical hypothesis testing, helps to quantify whether a result is likely to have occurred because of chance or because of some factor or variable of interest.

Question 35

Determining significance can be done using many methods including:

Answer 35

including technical, collaborative, reasoned argumentation and composite approaches, and various methods and techniques are available to support such approaches, including Geographic Information Systems, simulation modelling, and statistical significance tests; data scaling and screening procedures, such as threshold analysis and constraint mapping; qualitative and quantitative aggregation and evaluation procedures, including concordance analysis, multi-criteria analysis, ranking and weighting, and risk assessment; and formal and informal public interaction procedures, such as open houses, workshops, and advisory committees

Question 36

cost-benefit analysis

Answer 36

An assessment method that expresses project impacts in monetary terms, measuring the relative costs of a project against its potential or total benefits.

Question 37

impact magnitude

Answer 37

matrices Impact matrices that provide some indication of the relative importance or significance of the affected components.

Question 38

fuzzy sets

Answer 38

A class of objects with a continuum of grades of membership or a mathematical model of vague qualitative or quantitative data.

Question 39

reasoned argumentation

Answer 39

The reasoned argumentation approach views significance determination as based on reasoned judgments supported by evidence. Lawrence (2005, p. 19) explains that reasoned argumentation starts from the premise that technical and collaborative models are “too narrow to provide an adequate foundation for value-based significance judgments about what is important and what is not important.” Usually expressed qualitatively, the reasoned argumentation model is evident at the regulatory level in priorities and objectives of EA legislation or regulation, often defining “matters of significance,” which are used as triggers during the screening process and further expressed in project-specific guidelines and requirement

reasoned argumentation Sifting through information, data, perspectives, and expressed values using structured methods (e.g., decision support aids, matrices, network diagrams) to focus on matters of most importance to decision-making and to build reasoned arguments that support a claim or position.