Brownfields Redevelopment  Toolbox

Step 1 - Step 2 - Evaluation

Step 2 - Evaluation (sub-directory)

 

Section Updated Dec. 2008

Contributiors to this section include:

  • Government of Ontario
  • Health Canada
  • Jacques WhitfordJacques Whitford

Conduct Research (due diligence)

In order for a municipality to evaluate the degree to which their assets and tax base are affected by brownfields and how they should prepare to deal with the brownfields issue, the municipality should conduct research as part of their due diligence on factors that will shape their Brownfields Redevelopment Strategy, Official Plan (OP) and Community Improvement Plan (CIP). The research should be detailed enough to provide the background and site characteristics for each site identified in the inventory as well as providing information to namely evaluate:

 
  • Presence of absence of likely ecological or human health risks;
  • Condition of existing structures, including presence or absence of designated substances;
  • Presence or absence of impacts beyond a given site's property boundaries (namely to municipal right of ways or services);
  • Sites and adjacent properties authorized and proposed land uses;
  • Environmental and financial risks and liabilities; and
  • Assess site rehabilitation costs(clean-up and structure demolition/rehabilitation costs).

External Working Group (External Team)

The Working Group or an external team may be engaged to conduct research on the identified sites in the land and building inventory. It is important for the Municipal Team to work with reliable parties that have a proven track record in assessment and remediation work. 

The market for selling redeveloped sites must also be researched and each brownfield site should be mapped for potential marketing. This market research and site map can also be used to complete future density plans and implementation of a Community Improvement Plan.

Environmental Site Characterization 

Site characterization is an important step towards evaluating the degree of contamination and the areas of concern within a site.

  • A well-characterized site can reduce the risk of unexpected expenses due to unforeseen remediation efforts, disposal and potential hidden liabilities.
  • Environmental Site Assessments (ESAs) provide site characteristics that will determine the scope of work needed to mitigate environmental, health and ecological risks associated with the property.
  • A detailed Risk Assessment can then evaluate the potential risks and pathways of contamination exposure to the human environment and/or to ecological receptors, if present. The Risk Assessment should include limits for acceptable exposure over short and long-term periods as well as constant versus periodic exposure.
An Environmental Site Characterization should include:
  • The size and location of the property
  • History of site
  • Stored chemicals (both on the site and on neighbouring properties in the vicinity)
  • Use and history of neighbouring properties
  • Presence or absence of areas designated as sensitive or of potential natural significance (e.g., water courses, well head protection areas, shallow soil areas, areas host of designated or protected species, etc.)
  • Contamination and areas of concern
  • An evaluation of risk exposure to workers and general public during cleanup and at final land usage.
    Risk exposure to workers and general public during cleanup and at final land usage.
A detailed site characterization should provide the data to determine economic viability of the site from a cleanup perspective in order for a developer to assess the worthiness of a property. Is this site a positive, neutral or negative value site? 

Physical Due Diligence and Building Condition Survey

An evaluation of the condition and potential for re-use of structures present at Brownfields site is a critical element to evaluate the full re-development potential or financial liability of any project.

  • Significant site features and structures should be assessed to identify the presence or absence of designated materials (as defined in the provincial and federal regulation) or hazardous substance. Should they be present, the need for abatement or repair work should be identified along with associated costs
  • Site features and buildings should be inspected for structural, envelope and cladding soundness.

A well executed physical due diligence program should be able to identify the potential for optimal re-use of a site's features along with potential refurbishing costs, or to evaluate the level of effort and cost to complete abatement and demolition work, if necessary of selected.
Environmental Site Assessment

Environmental Site Assessments, are generally composed of a Phase I Environmental Site Assessment (Phase I ESA) and a Phase II Environmental Site Assessment (Phase II ESA).

The minimal requirements for Phase I and II ESAs are now prescribed by legislation in Ontario when the use of a site is to change to a more sensitive land use (e.g., commercial to residential, etc.). The regulation is outlined under the Brownfields Statute Law Amendment Act, 2001 and Ontario's Brownfields Legislation and Records of Site Condition Regulation (O. Reg. 153/04). Requirements of the ESAs must be followed if the Phase I and II ESA are to be used as part of filing a Record of Site Condition (RSC). The RSC requirements follow the Canadian Standards Association (CSA) Standard Z769.

A Phase I Environmental Site Assessment (Phase I ESA)  

A Phase I ESA identifies potential liabilities associated with contaminants in soil, sediment, ground or surface water through site inspection and historical review. Phase I ESAs are non-intrusive investigative research conducted to obtain as much detailed site history as possible without having to sample and analyze the site. A Phase I ESA is composed of a preliminary assessment of the site and of properties in the vicinity of the site which is the process of collecting and reviewing available information about known or suspected hazardous wastes storage, spills, releases and contamination. Typical characteristics associated with brownfield properties include soil, sediment, surface water and/or groundwater impacted by former operations, stored or buried infrastructure, chemicals, waste, hazardous materials and spills or illegal disposal.

Components of a Phase I ESA include:

  • Historical research
  • Regulatory request for information
  • Site investigation (visit/interviews)
  • Report preparation

A Phase I ESA may be conducted through:

  • Research of old municipal records, maps, photographs, etc.
  • Interviews with the neighbouring properties and local community, etc.
  • Site visits, considered non-intrusive, which involves walking/touring property to observe evidence of impacted areas, storage areas and containers.
  • The site visit should include interviews with staff and former staff as well a review of operational reports and logs.
  • Identification of potential ‘Areas of Concern’

Phase II Environmental Site Assessment (Phase II ESA)

A Phase II ESA is an intrusive investigation and assessment of a property's, surface and subsurface media. These may include sections within a brownfield site, the entire property itself and physical pathways to human exposure and off-site migration. A Phase II ESA investigates and confirms the environmental condition of the 'Areas of Concern' identified through the Phase I ESA and determines the site characteristics (chemicals, contamination and concentrations) present to the extent of the investigation performed. This data is necessary to file a Record of Site Condition (RSC) and perform a Risk Assessment.  

The Legal Framework section outlines the circumstances under the Regulation at which a Phase II ESA must be performed or is exempt.

Components of a Phase II ESA include:

  • Assessment of ‘Areas of Concern’ identified under Phase I ESA
  • Planning of a site investigation
  • Conducting the site investigation
  • Interpreting and evaluation information gathered through the site investigation
  • Preparation of a written report
  • Submission of the written report to the client

Based on the findings of the Phase II ESA, the study team may identify the need to implement appropriate remedial actions and/or complete a risk assessment. Recommendations to complete responsible care for the impact identified and adhere to regulatory compliance may be issued further to the completion of the Phase II ESA.

A Phase II ESA may be conducted through:

  • Sampling of stored substances, and surface media (soil, sediment, groundwater and surface water)
    • Soil surface sampling
    • Water samples from on-site and nearby surface water bodies
    • Discharges into sewage and stormwater drainages
  • Subsurface sampling of soil and groundwater can be conducted through:
    • Borehole drilling and core sampling
    • Water wells
  • Subsurface sampling of vapours (off-gas) or indoor air quality monitoring (releases and establishment of background levels) can occasionally be performed for:
    • Particulates
    • Carbon monoxide
    • Toxic gases
    • Volatile contaminants of concern off-gasing

 
Risk Assessment
Risk Assessments are the scientific approach to evaluation and quantifying the degree of ecological and human health risks associated with a contaminated site. This includes the type of contamination, the exposure pathways (bioavailability) and degree of bioaccumulation and its effects on human health and safety from current conditions and/or the end usage conditions once the site is redeveloped, with or without completing remedial actions(remediation may be mandatory based on regulatory requirements or the risk evaluation completed as part of the Risk Assessment, or voluntary based on the criteria of the proponents).  

Remediation of brownfields to site specific remedial targets developed further to a Risk Assessment approach is becoming more common as it is often almost impossible, impractical or prohibitively expensive to remediate a site to generic standards. The cleanup of contaminated sites and the redevelopment of brownfields are largely determined by economic viability. Increasingly, with new remedial technologies and risk evaluation techniques, risk-based remediation solutions are becoming the norm, particularly when certain types of contaminants are involved.

In Ontario, the Ministry of Environment (MOE) has now defined the requirements of Risk Assessment under O. Regulation 153/04. This regulation is defined under the Legal Framework (Step 2).

  • Risk Assessments were formerly known as “Site Specific Risk Assessments” (SSRAs). Under previous Ontario Guidelines, the review and acceptance process of SSRAs was often slow, unpredictable and uncertain.
  • The legislation now provides time limits for the MOE to review Risk Assessments and the new regulation prescribes standard forms for each stage of the process.
The following are the components of a Risk Assessment in Ontario:
  • Preparation and submission of a pre-submission form
  • Assessments of human health risk and of ecological risk
  • A written risk assessment report, following a mandatory report format that includes a description of the assessments of human health and ecological risk.

The Legal Framework of a Risk Assessment in Ontario is described in greater detail under the Toolbox Section: Legal Framework: Risk Assessment 

Did you know?

Provincial regulatory agencies offer different guidelines on many aspects of a risk assessment. A standardized guidance document should be adopted at the provincial and federal levels to assist with the consistent assessment of risks posed by contaminated sites across Canada. 
Pronvice of Ontario: The Ministry of the Environment is the lead department within the Province.

A standardized guidance docuement on how to undertake a Risk Assessment is under development for the Province of Ontario.

Federal Government Agency: Health Canada is the lead with respect to Risk Assessments. 

Federal Guidance Documents related to Human Health Risk Assessment are available and are intended for use by federal government custodial departments responsible for the assessment, management and/or remediation of contaminated sites in Canada, and their consultants, to conduct assessments of the human health risks associated with federal contaminated sites.

These documents may also be of use to other jurisdictions and levels of government needing to assess, manage, and/or remediate contaminated sites in Canada.

The Preliminary Quantitative Risk Assessment guidance documents below are currently being revised, and should to be completed by Spring 2007:

  • Federal Contaminated Site Risk Assessment in Canada, Part I: Guidance on Human Health Preliminary Quantitative Risk Assessment

  • Federal Contaminated Site Risk Assessment in Canada, Part II: Health Canada Toxicological Reference Values

  • Federal Contaminated Site Risk Assessment in Canada, Part III: Guidance on Peer Review of Human Health Risk Assessments for Federal Contaminated Sites in Canada

  • Federal Contaminated Site Risk Assessment in Canada, Part IV: Spreadsheet Tool for Human Health Preliminary Quantitative Risk Assessment

The following guidance documents are being developed:

  • Federal Contaminated Site Risk Assessment in Canada, Part V: Guidance on Complex Site-Specific Human Health Risk Assessment for Chemicals (expected in Spring 2007)

  • Federal Contaminated Site Risk Assessment in Canada, Part VI: Guidance on Human Health Risk Assessment for Radiological Contaminants(expected in Summer 2007)

  • Federal Contaminated Site Risk Assessment in Canada, Part VII: Guidance on Human Health Risk Assessment for Microbiological Contaminants(expected in 2008)

  • Federal Contaminated Site Risk Assessment in Canada, Part VIII: Compendium of Canadian Human Exposure Factors for Risk Assessment, 2nd Edition (expected in 2008)

Resources available at http://www.hc-sc.gc.ca/ewh-semt/contamsite/risk-risque-eng.php

 

Remediation Costs and Options
 
In order to address the next steps in evaluating financing needs, liability concerns and risk management techniques, the municipality must evaluate the Remediation Costs and Options that may be implemented on the site. Therefore, the municipality must understand the risks identified and the remedial options and costs available as suggested by their consultant.

Remedial plans presented to the Municipal Team should include options and costs for the implementation and execution of:

  • Remediation technologies (proven or new)
  • Cleanup techniques
  • Detailled designated substances mitigation or abatement program
  • Estimated timelines to completion for each proposed phase and options
  • Contractual services
  • Waste reduction, management, transportation and disposal program
  • Noise pollution barriers
  • Air pollution mitigation
  • Monitoring techniques (short and long term)
  • Phased remedial and construction work (stages and timelines)
  • Insurance premiums
  • Exit strategy
It should be noted that there are numerous proven technologies and remediation options available today. There is no single technology that outperforms all others in a given situation. This is because there are numerous factors involved in contaminated sites that vary from site to site and influence the technology or combination of technologies that should be implemented, such as:
  • Type and concentration of contaminant(s)
  • Media in which the contaminant occurs
  • Depth and access to contamination
  • Health and safety concerns
  • Environmental protection required
  • Use and expense of in-situ and/or ex-situ techniques
  • Use of proven technologies
  • Surface and sub-surface physical and chemical conditions
  • Physical constraints of location and time
  • Standards to which the site must be remediated based on regulatory compliance or risk assessments
  • Intended site features once re-development is completed

Technologies typically fall under the following categories:

  • Source Removal and off-site Disposal
  • Bioremediation/Phytoremediation
  • Chemical Oxidation
  • Thermal Destruction
  • Extraction/Separation
  • Collection
  • Barrier/Containment
  • Dredging/Excavation
  • Other unique technology categories

The cost of remediation, type of technology/service and time involved to remediate on-site or remove contaminants off-site for remediation as well as the opportunities to manage contamination on the site in light of the planned redevelopment program often determine which technologies or options to choose from based on site-specific conditions.

Following the Phase II ESA and a Risk Assessment, a Qualified Person should select the best option(s) to address the contaminants of concern. After addressing the social, health, economic, environmental, legal and liability concerns associated with the cleanup of the site and current/future use of the site and its surroundings, a choice must be made as to whether the site will be cleaned, to what level it will be cleaned, how much to clean on-site and off-site, whether to remove all materials, and what materials can be left on-site and reused. 

It should also be noted that if financing and insurance is required, quite often institutes that provide these services prefer the use of proven and reliable remediation technologies and techniques with predictable outcomes, costs and acceptance by regulatory bodies. The requirements and choices preferred by lenders are provided in Step 2, under the heading Financial Barriers: Lenders' Concerns and What the Lender Needs to Know.

 
Additional Tools and Resources on Environmental Site Characterization (Assessments and Risk Assessmetns) can be found on: