What is the remediation process for contaminated sites in the NWT?

Assessing, remediating, and monitoring contaminated sites is guided by the GNWT Approach to Contaminated Sites Management. The GNWT determines the approach to remediation of a contaminated site based on land use, the feasibility of remedial technologies, cost, and public and regulatory acceptance. Remediation is guided by the applicable environmental standards and legislative requirements. 

1. Identification of a Site – A site is identified as a potential contaminated site.
2. Phase I Environmental Site Assessment (ESA) - The process, as outlined in CSA Standard Z768-01, by which a qualified professional determines whether a property is, or may be, contaminated. This is most often completed through a records review and site visit. Phase I ESA reports must be submitted to the applicable regulatory authority.
3. Phase II ESA - If a Phase I ESA determines the site is contaminated or there is the potential for the site to be contaminated, a Phase II ESA is completed. The process, as outlined in the CSA Standard Z769-00, by which a qualified professional characterizes, determines concentrations, delineates, and quantifies contaminants at a site. The Phase II ESA involves the collection of samples (soil, groundwater, surface water, and/or sediment) to determine/confirm if contamination is present, what contamination is present, the concentration of contaminants, where the contamination is located and what media (soil/groundwater/surface water/sediment) are impacted. The Phase II ESA reports must be submitted to the appropriate regulatory authority.
4. Phase III ESA - A Phase III ESA is completed when contamination found during a Phase II ESA determines that additional sampling is required to gather more site information. If the initial Phase III ESA does not fully achieve its goal, supplemental Phase III ESAs will be carried out. The Phase III ESA reports must be submitted to the appropriate regulatory authority.
5. Human Health and Ecological Risk Assessment (HHERA) – HHERAs are typically required when removal of a contaminant of concern is deemed extremely difficult and/or cost prohibitive. If required, an assessment by a qualified professional determines the nature and probability of adverse health effects on humans and the ecosystem if exposed to contaminants identified by the ESAs. HHERA reports must be submitted to the applicable regulatory authority.
6. Risk Management Plan (RMP) – A RMP would follow the assessment phases supported by an HHERA. A RMP describes the steps and procedures required for managing risks identified in the HHERA. The RMP must receive approval from the applicable regulatory authority prior to being implemented.
7. Remedial Options Analysis (ROA) – A ROA is the process of evaluating different remediation methods for cleaning up a contaminated site and selecting the most reasonable remediation solution. The ROA considers factors such as cost, ease of implementation, length of time to complete the remediation, and effectiveness of the remediation method to reduce the concentration of contaminants. 
8. Remedial Action Plan (RAP) - A RAP is a plan that identifies site specific remedial objectives and actions for a contaminated site; outlines their feasibility; describes a preferred conceptual remediation plan and monitoring plan; and, if appropriate, requirements for on-going site management. The RAP needs to be submitted to the applicable regulatory authority for review and approval prior to being implemented.
9. Remediation – Includes performance of the site remediation works carried out by consultants and contractors in accordance with the approved RAP, engineered designs, and specifications. A remediation report detailing activities completed must be submitted to the appropriate regulatory authority.
10. Monitoring – Includes any post-remediation inspections, monitoring and/or maintenance activities that may be required. Monitoring is the process of routinely collecting samples from soil, groundwater, surface water, and/or sediment to assess the changes in contaminant concentrations over time and to see if it is moving. The data obtained from environmental monitoring can be used to evaluate the effectiveness of remediation or risk management actions. Monitoring reports generated need to be submitted to the appropriate regulatory authority.
11. Site Closure – Upon completion of both remediation and monitoring, or if post-remediation monitoring is not required, a site closure report must be completed and submitted to the appropriate authority for site closure approval. This will need to be completed for all regulatory authorizations.