Sarah Murphy – Environmental Remediation
I completed my co-op for the Earth Resource Technician Program (ERT, now known as the Geological Technician Program) as an Environmental Remediation Student with Canadian Nuclear Laboratories (CNL). Overall, my position was largely administrative which meant that I spent a lot of time at a desk. However, my position provided me with the opportunity to learn a lot about the construction process, quality assurance, compliance and policies associated with projects handling low-level radioactive waste (LLRW).
On a day to day basis I would attend meetings with engineering and project teams, record minutes, manage and file truck tickets including Transportation of Dangerous Goods documentation, and quality check waste haul records (i.e. the type and amount of waste coming into the long-term storage facility). As such, my tasks were largely divided into two categories:
- Administrative support for the construction and compliance documentation of the Long-Term Waste Management Facility (LTWMF).
- And daily waste tracking of LLRW coming from various remediation activities under the Port Hope Area Initiative (PHAI) to the LTWMF.
About CNL’s Port Hope Area Initiative (PHAI)
CNL is a nuclear science and technology organization that focuses on restoring and protecting Canada’s environment, clean energy technologies and medical applications. During my placement at CNL, I worked alongside the staff on the PHAI which focuses on the remediation and safe, long-term storage of historic LLRW in the municipalities of Port Hope and Clarington. This historic waste and contaminated soil contains contaminates such as radium 226, uranium, and arsenic which were produced as by-products of the refining process of radium and uranium by Eldorado Nuclear Limited, a historic Crown Corporation. The construction of the Port Granby and Port Hope LTWMFs provide safe storage and long-term monitoring of historic low-level radioactive waste that is excavated during cleanup, operations in the area. This and other information about PHAI can be found on the PHAI web page linked below.
LTWMF Construction
During my time at CNL I supported construction operations by helping to prepare documents for review and approval. I had the privilege to be involved with two LTWMFs, each at very different stages of construction and remediation. The first is the LTWMF in Port Granby, where remediation of the former waste management facility was completed in 2020 (Figure 1). While I was at CNL, the activities at Port Granby were largely focused on capping and closing the storage mound and re-vegetation of the area (Figure 2). One larger project on site was the removal of box culverts that were used to create a temporary access road between the former site and the LTWMF so that no waste would travel on municipal roads, a community-identified requirement of the Environmental Assessment (Figure 3).
The second LTWMF, located in Port Hope, was very much an active construction and waste placement site. During my time at CNL, contractors were constructing the base of a new cell for waste placement (Figure 4). These construction activities tied in closely with the application of soil mechanics in making sure that materials meet spec for its intended purpose. During the construction processes, there was an emphasis in oversight and quality assurance of the construction of the cell to meet specifications. This included running dipole testing to ensure there were no potential leaks in the liner and surveys to ensure that each layer in the cell met the specified depth for construction.
LTWMF daily waste haul operations
One of my main tasks for Port Hope was to track waste that was coming in from various sites to be placed in the cells at the LTWMF and make sure that all appropriate documentation (such as the Transportation of Dangerous Goods manifests, Trip tickets and Scale tickets) were accounted for. This involved checking the quality of the data, making sure it all lined up and made sense in order to provide contractors with weekly waste totals. This would be used both for invoice purposes and to track the remaining capacity of the cell.
Safety and Training on Site
CNL is very conscious about the safety and training of its employees and contractors. Training and orientation throughout my first couple of weeks with CNL included fire safety and prevention, orientation on health and safety for new and young workers, workplace violence and harassment prevention, Workplace Hazardous Materials Information System (WHMIS) and Group 4 radiation protection training.
Throughout my term with CNL, it was clear that it fostered a high-reporting culture where safety issues and incidents of any nature were reviewed, assessed and discussed to prevent future occurrences. It was always encouraged to have a questioning attitude and bring concerns to supervisors prior to starting work and notify them of hazards that could be eliminated or reduced. As with safety discussions at Fleming, it was emphasized that Personal Protective Equipment (PPE) is your last line of defence towards various hazards on the worksite, with hazard reduction and appropriate mindset/behaviour being a precursor to safe practices.
When on site we were required to have PPE including hard hat, high visibility vest, safety glasses and steel toe boots. In addition it was required to wear a thermoluminescent dosimeter to track the worker’s exposure to radiation. Gloves and hearing protection were to be carried on the person at all times while on site.
Environmental and Earth Resource Technology on Site
There was a lot of technology used on site between quality assurance and environmental monitoring applications. For length’s sake I will only name a few, but pretty much everything learned in our courses at Fleming was used at some stage of the project.
- Surveying throughout the construction of the cell is common to ensure that the different layers within the cell meet the required elevation based on depth specifications. At Fleming College we practiced using equipment such as automatic levels and total stations referenced to a known elevation and location to identify the relative elevation of a number of sample locations. At the LTWMF the surveyor used Global Navigation Satellite System (GNSS) receivers, base, rover and a TSC 3 Ranger data collector to obtain this information.
- Dipole testing: This is an active geophysical survey method (meaning it uses an induced current) that is used to identify potential cuts, leaks or dents in the High-Density Polyethylene (HDPE) liner. By identifying anomalies in the electric current running through the liner, the contractor is able to locate and repair potential issues in the liner after drainage stone has been placed over top. This helps identify any issues that could have occurred during the placement of the stone or that may have been so small that it was missed during the visual inspection of the liner (such as scuffs or pinholes). CNL was my first exposure to this technology.
- High volume air samplers: These were used for air and dust monitoring. Given the nature of the waste being largely soil, air and dust monitoring is huge for this project with stations being checked on a daily basis for exceedances, both by CNL and an independent environmental contractor. I had been introduced to this equipment previously at Trent University but not Fleming College as it is more popular in environmental monitoring programs.
- Pancake monitor: Used to identify contamination and scan people out of radiological zones. CNL is the first place that I have seen this equipment.
Throughout my time at CNL other “buzz” words as related to the ERT program include boreholes (sampling and logging), piezometers, X-ray Fluorescence Spectrometers (XRF), Geographic Information Systems (GIS), AutoCAD, radiological surveys and elevation surveys. In addition samples such as clay (Shelby tube samples), drainage stone, and geotextiles would be sent to labs to ensure that the material met specifications so that construction or purchase could advance.
Most relevant courses
Most of the courses that I took at Fleming College did appear in some capacity on site, whether the associated tasks were conducted through CNL, its contactors or subcontractors. In the context of environmental remediation projects, it is very evident that the present themes resemble those of the construction industry as opposed to the mineralogy and petrology of the area.
Based on my experience at CNL, I would say that the prominent ERT courses used in remediation efforts include:
- Geophysical Methods
- Principles of Hydrogeology
- Sampling Protocols
- Stability of Earth and Structure
- Surveying
- Geo-Environmental Site Investigations
- Soil Mechanics
Going Forward
I think the unique context of CNL as an LLRW remediation project was a huge opportunity, and I enjoyed engaging with the science and policy involved in my job. I would recommend CNL as a co-op to those who are interested in policy, stakeholder relations, environmental monitoring and coordination opportunities.
References and resources
For those interested, opportunities at CNL are posted on the company’s web page at https://www.cnl.ca/about-cnl/work-with-us/
As for me, I have come to appreciate that I enjoy jobs that are a bit more physically demanding and may look for future opportunities in the field of surveying.
Port Hope Area Initiative (2016). About the PHAI. Retrieved from https://www.phai.ca/en/home/phai/about-the-port-hope-area-initiative/default.aspx.
