Reference Guide on Physical and Cultural Heritage Resources: 4. A Framework for Evaluating the Potential Environmental Effects of a Project on Cultural Heritage Resources

4. A Framework for Evaluating the Potential Environmental Effects of a Project on Cultural Heritage Resources

In general, an assessment will consist of several procedural steps such as scoping, analysis, determination of significance, development of mitigation measures, and development and implementation of a follow-up program. These steps are iterative rather than linear; circumstances commonly arise during the course of an assessment that require these steps to be revisited. The assessment procedure, including the different steps one has to consider, is captured in a case study provided at the end of this section.

Public participation is a critical element throughout the assessment process and input from the public should be sought from the initial stages of proposed projects. This can be beneficial by integrating local knowledge at the planning phase of projects.

Further, it is important to note that trained professionals in cultural heritage resources should be involved throughout the assessment of the project, as appropriate.

Step 1. Scoping

Effective scoping focuses the EA analysis on relevant environmental issues and concerns arising from a proposed project.

Scoping for cultural heritage resources should consider the following:

A. ldentify cultural heritage resources and other relevant information

The first step in a scoping exercise is to identify cultural heritage resources located on- and off-site which potentially could be affected by the project. To do this, it is necessary to assess the potential for the presence of cultural heritage resources first through a site survey or inspection, then identify and evaluate them. This would also provide information on the significance of the cultural heritage resources that may be affected by a project. Once the geographical area and the significance of the resources have been identified, then identification of site boundaries should follow. During this early phase of the project, project site boundaries should remain flexible at least until all cultural resources have been identified and consensus among project team members has been satisfied.

Background information may include historical events and key characteristics of the area, particularly with respect to the culture and important heritage values of those living in the area.

The scientific significance of heritage sites is also an important aspect to be considered when assessing a heritage site. Any sites recognized for their heritage value should be identified in an environmental assessment.

Possible sources of information to assist in identifying potential for or the presence of important cultural heritage resources include:

  • lists of national parks, national historic sites, and historic canals (Parks Canada);
  • federal and provincial registers of archaeological sites (see Appendices 2 and 3);
  • Canadian Register of Heritage Properties (Parks Canada);
  • Federal Heritage Buildings Register Office (FHBRO);
  • federal and provincial government departments responsible for heritage issues (see Appendix 1);
  • aboriginal communities;
  • academic and research institutions;
  • professional societies and organizations;
  • federal, provincial and municipal archives and libraries;
  • museums;
  • land use plans;
  • local citizens or associations involved in the area of heritage conservation and protection; and
  • ICOMOS Canada (International Council on Monuments and Sites).

Pertinent questions to ask when identifying cultural heritage resources include, for example:

  • What are the main heritage characteristics and resources of the area which may potentially be affected? Is this area, or any part of it recognized to have any heritage or cultural value in terms of archaeology, history, science, architecture, engineering and natural history?
  • Was there any exploratory work previously undertaken, in order to identify archaeological sites or artifacts in the proposed project area? Was there any similar type of work done to identify the cultural values of the proposed project area?
  • What was the scope and thoroughness of previous work, and is it adequate for current purpose?

B. Identify spatial and temporal boundaries of the project

Boundaries for Cultural Heritage Resources

Setting boundaries for cultural heritage resources must be planned within the project area. Although in some instances, the cultural heritage resources might be a distance from the core area of the project and might be affected by the project, inclusion of these cultural heritage resources could be considered within the boundaries of the project.

It is important to remember that the Act requires to assess any change on cultural heritage resources resulting from changes in the environment caused by the project. This must be kept in mind when establishing boundaries for a project.

Boundaries Associated with Cumulative Environmental Effects

Cumulative environmental effects is defined as,

“the effect on the environment which results from effects of a project when combined with those of other past, existing and imminent projects and activities. These may occur over a certain period of time and distance.”
(RA Guide 1994).

When identifying spatial and temporal boundaries the cumulative environmental effects which could result from the project must be considered. Defining the spatial and temporal boundaries establishes a frame of reference for assessing cumulative environmental effects and facilitates their identification. Such boundaries can also influence the assessment in a variety of ways. If large boundaries are defined, only a superficial assessment may be possible and uncertainty will increase. If the boundaries are small, a more detailed examination may be feasible but an understanding of the broad context may be sacrificed. Proponents may perceive assessments with large boundaries as onerous or unfeasible, whereas the public may think small boundaries do not adequately encompass all of the project's environmental effects.


  • Different boundaries may be appropriate for different cumulative environmental effects. For example, the boundaries selected for cumulative environmental effects on air quality might be quite different than those chosen for effects on cultural heritage resources;
  • Spatial boundaries should extend beyond a project's immediate site to include the area likely to be affected;
  • Temporal boundaries may extend beyond the timing of construction and operation to include the period of occurrence of the effects.

Most importantly, the boundaries of an assessment should be reasonable. In many cases, it will be appropriate to consult with the affected public in making this determination. Whatever boundaries are set, they may influence the determination of significance, because the effects including cumulative effects of the project on cultural heritage resources may be very significant locally, but of little significance regionally.

C. Identify potential environmental effects on cultural heritage resources

The term “environmental effect”, defined in Section 2(1) of the Act, includes the effects on physical and cultural heritage which may result from changing environmental conditions caused by a project. For further clarification on environmental effects, refer to section 1.4 of the RA Guide.

The following questions should be considered:

  • Will environmental effects resulting from a project, either beneficial or deletarious to the environment, could adversely affect the cultural heritage resources?
  • Are there other past, existing or imminent projects or activities which are currently or may in the future, affect the identified cultural heritage resources? Will these cumulative effects adversely impact the cultural heritage resources?
  • Do members of the community demonstrate any concern about the proposed project? How do they value their cultural heritage resources? How will they view their cultural heritage resources being adversely affected by an undertaking?

The responsibility over heritage matters is shared by several jurisdictions and consultation with other government agencies is an essential aspect of the assessment. The public must also be consulted, preferably in the early planning stages of the project, to ensure that community values and concerns have been considered in an environmental assessment.

Scoping for Cultural Heritage Resources

  • It was determined during the scoping phase of the Oldman River Dam project in Alberta, over 300 archaeological sites were identified, of which approximately 170 were potentially being directly affected by the flooding of land in the foothills. The scoping involved both pre-field scoping work and in-field survey, and initial test excavations. The project area was considered by the Peigan as the heartland of their traditional territory.
  • The construction of a runway at an international airport, required the removal of an historic parish cemetery dating back to 1833. Further study was necessary to determine the significance of these effects on the historic cemetery and identify possible mitigation measures.

Step 2. Analysis of the Potential Effects on Cultural Heritage Resources

The objective of the analysis is to describe how the potential environmental effects of a project may affect cultural heritage resources. This phase of the assessment should include:

  • A description of the nature and current status of the resources, including important characteristics and current assessment of stressors, such as adverse effects of acid rain caused by past and current projects and activities on historic buildings; the natural erosion of an archaeological site; changes to the cultural landscape around a historic church, etc.;
  • Assessment of the potential effects the project may likely cause to the cultural heritage resources;
  • Consideration of cumulative effects of past, existing and future projects and activities in the proposed project area, all of which may have the potential of affecting the same cultural heritage resources and the overall heritage value of the area; and
  • An analysis of the results of the consultations held with the public and stakeholders.

Early Consideration of Heritage Resources in Environmental Assessment

  • Early consideration of the potential impact of actions to safeguard one category of cultural heritage resources at the Motherwell Homestead National Historic Site enabled action to be taken to safeguard another category of cultural heritage resources. Due to the requirement to provide fire protection, fire hydrants had to be installed on this historic site. The traditional approach would have been to install fire hydrants which required buried water pipes and consequently, the excavation of a large trench through the site, However, by considering all cultural heritage resources in the early planning stages, the project manager changed the project design by employing a horizontal boring device allowing for insertion of the water pipe underneath the cultural layers. In addition to conserving the cultural heritage resources, the need for extensive and costly backfilling and vegetation rehabilitation was also minimized.
  • Plans to build a sewage lagoon threatened to destroy the Bernard Site, an archaeological site, on the Tobique Indian Reserve in New Brunswick. Although the potential of the Bernard Site to contribute significantly to Aboriginal history had been recognized for many years, it had never been properly investigated. Concerns within the local population over the threat to this cultural heritage resource, in addition to other health and safety factors, developed into strong opposition to the proposed project site. This led the Band Council to determine that an archaeological assessment of the project area was required. The assessment was undertaken using federal and provincial expertise and funds jointly provided by the Band and the province. It confirmed the site's value as an important heritage site and also significantly raised public awareness of archaeological heritage by involving the local community at all levels of the investigation. Ultimately, once all the factors were considered, a decision was made to relocate the sewage lagoon.

Step 3. Determination of Significance of Adverse Effects

The Act requires the RA to determine whether the project is likely to cause significant adverse environmental effects. While consideration of the significance of various forms of physical impacts on heritage resources is important, they must be balanced with a firm understanding of the historic, archaeological and cultural significance of the resources in question. These issues must be explored if mitigation is to be effective which is also a reason to consult with professionals at the onset of a project with a potential of having cultural heritage resources.

In the case where impacts on cultural heritage resources are the only significant impacts identified in the overall context of the project, it is at the discretion of the RA to make a decision on whether the project would be determined to cause significant environmental effects. In making a determination on significance, the following questions should be considered:

  • Will the project cause any adverse effects on cultural heritage resources?
    • An adverse effect on cultural heritage resources is one which destroys elements essential to the heritage character or introduces elements that are damaging or detrimental to the heritage character. Table 1 presents examples of adverse effects on cultural heritage resources as a result of a project causing a change in the environment.
  • Will these effects be significant in terms of causing any alterations to the state of the cultural heritage resources?
    • The following aspects of the various environmental effects (as they affect cultural heritage resources) should be considered:
      • magnitude;
      • geographic extent;
      • duration and frequency;
      • reversibility;
      • context.
  • Will the project affect the cultural heritage resources in a way that contributes, either additively or synergistically, to existing effects from other past or pesent projects, or effects that will likely stem from future projects? If so, the significance of these total effects must be considered, regarding the potential to:
    • illustrate historic themes, provide a view on the past, or portray a historical event which occurred in the area;
    • evaluate whether a cultural resource can physically survive the impacts of cumulative effects;
    • educate the public about the value of our cultural heritage;
    • provide for the spiritual and cultural purposes of the site; and
    • promote further research.
  • How likely are these effects to occur?
Table 1: Examples of adverse effects on cultural heritage resources resulting from a change in the environment
Change in the Environment Effects on Cultural Heritage Resources
Land disturbance and transformation of natural landscapes (e.g. soil compaction, dredging, digging, filling, clearing, etc.)
  • Effects on a conservation area
  • Effects on special historic or cultural landscapes or site
  • Damage, disturbance or destruction of archaeological remains or sites
  • Disturbance of spiritual sites
  • Spoiling of the setting of heritage building, structure or site
Effects of underground construction
  • Deterioration of an architectural or historic building or monument caused by vibration
Demolition or construction of buildings or other structures
  • Destruction of heritage buildings or archaeological sites
  • Spoiling of the setting of heritage building, structure or site

For more detailed information on determination of significance refer to the RA Guide.

Step 4. Design of Mitigation Measures

Consultation with heritage experts is strongly advised to ensure that appropriate mitigation measures for cultural heritage resources are implemented. Although a range of measures could be deployed to mitigate impacts on cultural heritage resources, those chosen must fit the type and scope of a project. Mitigation measures must be technically and economically feasible and could include:

  • Re-siting of the project to avoid sensitive areas such as significant sites or areas known to contain cultural artifacts, significant cultural landscape, etc.;
  • Changing the project design or construction techniques and technologies to reduce effects of the project on cultural heritage resources;
  • Implementing site protection such as stabilization practices, fences, monitoring, etc.;
  • Conducting professional rescue archaeology to salvage archaeological resources and their contextual information prior to their damage or destruction;
  • Changing site maintenance practices causing damage to historic fabric, e.g. road salt on stone walls.

Mitigating Effects on Cultural Heritage Resaurces

  • The mitigation measures for the Oldman River Dam project in Alberta included the removal of objects and buildings from the development area. As part of the mitigation measures for construction of a reservoir, the Government of Alberta undertook an archaeological mitigation program as required by the Historical Resources Act of Alberta. Implementation of the mitigation program was undertaken by professional archaeological consulting firms.
  • In the case of a runway project at an international airport, the removal of a historical cemetery was to be carried out in a manner that respects the requirements of the Roman Catholic Archdiocese of the local municipality of the Roman Catholic Cemeteries Board.

Step 5. Follow-up Program

The objectives of a follow-up program are to verify the accuracy of the EA and determine the effectiveness of any mitigation measures that have been implemented. Section 16(2) of the Act requires that all comprehensive studies, all mediation and assessments by a review panel consider the need for, and requirements of a follow-up program. If it is determined that the project is likely to cause effects on cultural heritage resources and that a follow-up program is needed, then monitoring the effects on the cultural heritage resources may be included in the follow-up program.

While consideration of the need for follow-up is required for all but the screening phase of a federal EA, the determination of appropriateness and actual implementation of such a program is left to the discretion of the RA.

Case Study

The Project

A federal/provincial panel was formed to review and assess the proposed construction of a sewage treatment plant and oil-from-sludge facility on Ives Island at Ives Cove off the north end of McNabbs Island near Halifax. The project included the construction of the collector system, an artificial island and a diffuser.


Some members of the community felt that the project would result in the destruction and loss of access to the cultural heritage resources through the construction of the artificial island. These resources consisted of a careening yard, a concrete hut associated with Canadian military history, and possibly a Micmac historic site at Indian Point. The creation of the artificial island would also eliminate access to, and possibly destroy, other cultural heritage resources; three wooden shipwrecks in the shallow water off Ives Cove, usually accessible on foot from the beach at low tide. There was concern that the remains of historic vessels in the shipping channel could be lost due to construction of the diffuser.


The analysis confirmed that the concrete hut would be completely covered by the artificial island. It was also determined that the shipwrecks would possibly be disturbed by construction activities.

Mitigation measures

The measures proposed to mitigate impacts on land-based cultural heritage resource included testing and excavation by professional archaeologists to investigate cultural heritage resources occurring at the construction sites. Regular inspections were also proposed to ensure that any new cultural heritage resources discovered during construction activities would be assessed and mitigated appropriately using rescue archaeology.


The Panel recommended that Halifax Harbour Cleanup Inc. and the Environmental Effects Monitoring Committee design monitoring programs, as necessary, to provide a well-rounded cumulative effects monitoring program that would address the assimilative capacity of Halifax Harbour over the life of the project.

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