Erik Nickel, the Chief Operating Officer of the Petroleum Technology Research Centre (PTRC), shows a collection of images from seismic shoots that have taken place at the Aquistore CO2 injection site in southeastern Saskatchewan. The images – which illustrate the growth of the CO2 plum underground over a number of years – demonstrate what can be achieved in the measurement and monitoring of CO2 deep in the subsurface.
“We were a bit surprised, actually, that we could see a CO2-related anomaly after just 36,000 tonnes of injection,” says Nickel. “The Deadwood Formation (the saline aquifer into which the CO2 is being injected) is about 3300 metres underground and the fact that the seismic array we established above the site was able to actually image the plume so early in the process was exciting. We have since been able to confirm these images by other independent data sources and subsequent seismic surveys.”
Aquistore is a pioneering project for CO2 storage in Canada. It began injecting CO2 from SaskPower’s Boundary Dam CCS Facility in April of 2015. The SaskPower facility – which has now captured 5.5 Mt of CO2 – sends about 10% of its carbon dioxide to the Aquistore storage well, with the remainder being sold to Whitecap Resources for enhanced oil recovery at the Weyburn oil field. The Aquistore project is strictly for permanent storage, without EOR, and was designed to be the largest field laboratory in the world for investigating industrial-scale CO2 storage. So far over 540,000 tonnes of CO2 is in the Deadwood Formation from the Aquistore injection well.
“We started injection at Aquistore a few years before Shell’s Quest project began injecting CO2 near Edmonton,” Nickel notes. “The project, from its inception, offered the opportunity to test a number of measurement, monitoring and verification technologies at the site, to determine their efficacy and application for CO2 storage. The site continues to offer those kinds of testing opportunities for different companies wanting to see if their technologies are effective at monitoring deep CO2 storage.”
“We have both an injection and monitoring well at the site,” says Zeinab Movahedzadeh, Project Manager at the PTRC and responsible for Aquistore site management. “Both wells have downhole fibre optic sensors measuring temperature. And downhole pressure gauges are monitoring minute-by-minute, second-by-second as CO2 is injected, and this data is proving to be of great interest to new projects currently being planned in Alberta and Saskatchewan, and around the World.”
Fibre optic lines have also been trenched in various patterns on the surface, and are used during the seismic shoots at the site to produce images of the CO2 plume. These are compared with the permanent array of 630 geophones at site, and over the course of the past eight years have catalogued the improvements in fibre optic imaging technologies.
Aquistore and PTRC’s research program is now garnering interest, new memberships, and consultations from different companies involved in CCS. The federal incentives announced in 2022 add urgency to the development of CCS projects in Canada from large, set-point emitters, which means that Aquistore research findings and data are of significant interest to those players planning for the speedy implementation of storage projects by 2030.
“Our goal is to help Canada reach it’s Net-zero 2050 targets through the implementation of CCUS,” says Ranjith Narayanasamy, the PTRC’s President and CEO. “Aquistore’s learnings are proving to be of interest across many different industries looking to reduce their set-point emissions. We have over ten years of real, significant data from our project.”
The PTRC also managed the IEAGHG Weyburn-Midale CO2 Monitoring and Storage Project (2000-2012) and published results through a book from Geoscience Publishing in 2013 (Best Practices for Validating CO2 Geological Storage: Observations and Learnings from the IEAGHG Weyburn-Midale CO2 Monitoring and Storage Project). Data from that project is also proving to be of interest as CCUS projects gear up around the world.
“Being first at the plate has proven to be important for us,” Nickel says. “Our work at Aquistore is ongoing, with the possibility of a new observation well drilled directly into the CO2 saturated reservoir. This would offer a unique look at a CO2 flooded reservoir and allow us to gain valuable insight into the geochemical effects of CO2 on rocks and fluids. We are excited for what the future holds at the site.”
By Norm Sacuta, Director of Communications at Petroleum Technology Research Centre