Part 2: A Case Study in Uncertainty
by Lexa Ward and Rebecca Kauffman
This is the second part of our two-part introductory blog on liability management for oil sands tailings ponds. The first part, The Liability Management Context, provided a background to the main regulatory and policy instruments governing tailings management, including the Tailings Management Framework (TMF), the regulatory document Directive 085 (D-085), and the Mine Financial Security Program (MFSP).[1] In this second part we consider the challenges and uncertainty in how policy objectives can be met in part with a closer look at the first major project that will shortly move into the reclamation phase of work, barring any extensions: the Suncor Base Plant.
Base Plant: A Case Study
Suncor holds the first oil sands mining approval for the Athabasca oil sands, dating back to 1960.[2] This approval was for the now Base Plant operation, composed of the Millennium and North Steepbank mines.[3] Base Plant first began production in 1967, although Millennium and North Steepbank were not actively mined until 2001 and 2011, respectively. [4]
Base Plant will also likely be the first oil sands mine to reach its end of life, originally estimated to be 2033.[5] A mine’s end of life date is important because all fluid tailings reclamation timelines are set around this date, with some expectation for adjustment as the date approaches.[6] Specifically, legacy fluid tailings[7] must be “ready to reclaim” (RTR) by the mine’s end of life and new fluid tailings[8] must be RTR by ten years past the mine’s end of life.[9] For Base Plant, this would mean that legacy tailings must be reclaimed by 2033, and new tailings by 2043.[10] Note that as of 2022, the end of life date for this project was pushed back to 2036 with a new RTR date of 2046.[11] The project proponent has also recently applied for an extension which would have a lifespan of roughly 25 years.[12]
Regardless of whether this extension is approved, Base Plant will likely be one of the first oil sands mine projects to reach its end date and subsequently one of the first to face the challenges inherent to tailings pond reclamation. While specific dates may not be the crux of the matter, this ever-changing timeline does suggest a significant degree of uncertainty. Uncertainty that may impact when and how this reclamation is completed. Overall, even a 25-year extension would be minimal if the policy requirements set out in the TMF, such as progressive reclamation, were to be achieved. On the other hand, regardless of exact timing, observers have noted, “[a]s Suncor’s base mine has been in operation since 1967 … there is now little time left to manage the volume of fluid tailings that has accumulated over the last five decades.”[13]
Base Plant’s Tailings Management Plan
Suncor’s Base Plant tailings management plan (TMP) was one of the first to be submitted and approved under D-085 in 2017.[14]
The TMP sets out the AER’s conditions for Base Plant including that tailings management at the site remain in line with D-085’s requirements. This includes Base Plant’s fluid tailings volume profile[15] and the management thresholds for fluid tailings accumulation.[16] From the original Base Plant TMP, the total volume trigger was set at 281 Mm3, and the total volume limit at 393 Mm3.[17] The profile deviation trigger is more mutable and is ”based on a five-year rolling average of the annual profile deviation for the new tailings profile.”[18]
However, as of the AER’s State of Fluid Tailings report for the 2023 reporting year, Base Plant’s total volume trigger was then set at 272.0 Mm3, and the total volume limit at 380.8 Mm3.[19] This was a change approved by the AER in 2022 to better reflect the predicted fluid generation rate for the mines.[20] Based on Suncor’s 2025 report, describing their 2024 fluid tailings management, Base Plant’s fluid tailings volume was most recently at 277.77 Mm3.[21] This is 0.3 Mm3 below the approved fluid tailings profile for the reporting year (278 Mm3), which still puts the Base Plant operation on track to meet its stated reclamation goals.[22]
Since the institution of the D-085 fluid tailings measuring and reporting requirements, fluid tailings accumulation at Base Plant appears to have peaked in 2016, with a volume of 317 Mm3; still below their approved fluid tailings profile.[23] However, since 2023 there has been a notable upwards trend, from 267 Mm3 in 2022, to 270 Mm3 in 2023, and 277.7 Mm3 in 2024.[24] While the current volume is still below approved levels, it is not by much, and the upward trend, especially in comparison with the downward trend of the approved fluid tailings volume profile is concerning.[25]
The TMF sets an expectation that an approved fluid tailings volume profile will initially grow, then stabilize, before declining towards the mine’s end of life, considering opportunities for a growth in production.[26] However, even with opportunities for growth, the TMF continues to focus on progressive reclamation, specifying that “[a]s production expansions occur, it is expected that continuous treatment of tailings will not necessitate an allowance of volume accumulation seen at the Early Production stage of a project.”[27] The framework goes on to specify that in Phase 2 of a project, treatment of tailings will vary, “particularly as production increases and decreases over various phases.”[28] Again, the focus remains on progressive reclamation that should align with the amount of tailings fluid being generated at any time. As this project is nearing the end of its lifetime, progressive reclamation, even alongside an increase in production, should be the focus to ensure that the goal of RTR within 10 years can be met. However, even as recently as 2017, the base plant project was estimating that reclamation activities would not be concluded until 52 years after the end of mine life, which the Pembina Institute and the Oil Sands Environmental Coalition argue, demonstrates that the liability associated with these fluid tailings is “not being minimized with progressive reclamation.”[29]
There are also concerns that current reclamation at the Base Plant project site is being completed with reclamation technology that is still under evaluation for its efficacy. Specifically, Suncor reports that Permanent Aquatic Storage Structure (PASS)[30] technology was used to treat 21.3 Mm3 of fluid tailings at Base Plant in 2024.[31] More recent TMP approvals, such as the Fort Hills approval, were leery to approve the exclusive use of PASS for reclamation due to the generally untested nature of the technology.[32] While PASS was approved for use in the original Base Plant TMP, only the first stage of the technology was approved, not the less-tested stages, nor water capping,[33] so it is clear that the AER was still exercising caution around the use of this rather novel technology.[34] While Base Plant is actively using PASS (alongside other technology) for reclamation, it is unclear whether this will be a viable long-term reclamation strategy — especially with all the concerns expressed, by both the AER and stakeholders, around the use of water capping and pit lakes for reclamation, both of which are a key aspect of PASS technology.[35] In fact, D-085 specifies that if “water-capped fluid tailings technology is used to generate the inventory forecast… an alternative treatment technology to treat equivalent volumes of fluid tailings with associated implementation timeframes must be provided.”[36]
Contributions to the Mine Financial Security Program
As is the case for all oil sands mine operations, Suncor is required to pay into the MFSP to account for liabilities associated with the Base Plant mine. In 2023, the security held for the Base Plant operations was $359 096 654.[37] This amount represents a sizeable portion of the cumulative security for all oil sands mines, which is currently at $912 852 620, and is in fact the single largest security amount from any one project.[38] This sum represents Base Plant’s Base Security Deposit (BSD), as it was collected prior to the implementation of the MFSP formulae.[39] Before the MFSP, mine security was still collected from oil sands mines, however, there was no set formula for its calculation.[40] Mines who previously contributed security maintained that amount as their BSD after the MFSP’s implementation.[41] The Guide to the Mine Financial Security Program actually clarifies that the program is “an ongoing incentive to reduce liabilities to the maximum extent possible during the life of the operation” with tailings representing a significant portion of this liability.[42]
Since this initial deposit, Suncor reports that they have never been required to provide additional security.[43] This conforms with most other mines’ MFSP in Alberta, who do not appear to have had to provide security, other than the BSD, under the program.[44] This is despite the fact that there were opportunities in the past that could have caused security to be collected, and yet weren’t. Although the size of the BSD paid regarding the Base Plant project makes it an outlier, there are many projects without this large of a security deposit. Below, we summarize other opportunities for security payments options that may be necessary to ensure reclamation requirements are met. As Base Plant’s high initial security deposit was not required for other mines, these other forms of security would be necessary as supplement. We include them below to highlight why adequate security should be taken at the outset, as the other options are rarely utilized.
The asset safety factor deposit (ASFD) is one “non-necessary” financial security deposit that could have been collected upon but was avoided by the Government of Alberta when it temporarily changed the formula for asset calculation. This meant that mine operators, who may have otherwise had to contribute to the ASFD due to falling oil prices, avoided doing so.
The outstanding reclamation deposit (ORD), is also security that may only be collected in prescribed circumstances.[45] However, it does not appear to have been collected for any mines, including Base Plant.[46] The ORD, which may only be collected upon if the mine operator fails to complete their planned reclamation on schedule, has a disincentive built into its formula: the more reclamation is planned for, the higher the likelihood that the operator will fall short and therefore have to pay the ORD.[47] This is because the ORD payment is only triggered if the reclamation set out in project planning documents is not completed. If mine operators plan for a smaller amount of reclamation and exceed it, they will not trigger an ORD payment. Therefore, mine operators may be disinclined to plan for much reclamation, out of fear that they may fall short and owe security.[48] This concern may have affected Base Plant’s reclamation planning, where in the 2023 reporting year, they overshot their planned reclamation, completing the reclamation of 21.6ha of land, compared to the planned 20ha.[49]
As the Base Plant is (at present) within 15 years of its end of life (2036), it could also be required to contribute its operating life deposit (OLD).[50] However, the OLD is offset by the BSD, where the OLD will only be collected once the amount owed surpasses what is held under the BSD.[51] As Suncor’s Base Plant BSD is so high, it is possible that it will already fully cover all necessary abandonment, remediation, and surface reclamation work, and that OLD security will never need to be posted. Again, the Base Plant approach of a high initial security deposit, if applied to other mines would have been a better approach to ensure sufficient security.
While not explicitly stated, the fact that Base Plant BSD is so high that it could potentially cover all necessary reclamation and remediation work speaks in favour of having a high base security deposit. This is similar to the mine security programs of the Yukon and Québec, who require the full amount of security for the mine to be provided at the start of the mine’s life.[52] In contrast, Alberta’s current MFSP system, allows for the mine‘s liabilities to be offset by its assets.[53] A requirement for full upfront security provides a better guarantee that the necessary reclamation work will be conducted, and insulates the taxpayer from having to cover the cost of future reclamation.
Concluding Themes
Base Plant is not on its face a unique project in the Alberta oil sands, rather it serves to demonstrate that while there may still be decades left in the productive capacity of some of these mines, in many cases the end is fast approaching. And with it, the need to deal with the accompanying fluid tailings. Unfortunately, as of 2025 there is a limited liability management framework in place to ensure that the reclamation of these sites is complete. In particular, the stated goal of the TMF, progressive reclamation, has not been a focus of government regulation. Instead, if a project meets the basic requirements of the policy framework and associated Directive, reclamation continues to be pushed off into the future.
Aspects of the liability management framework, such as the high BSD held for Base Plant specifically, can be viewed as illustrative of a more conservative and precautionary approach to financial security being subsequently replaced by a policy with greater risk and uncertainty, that of the MFSP. The primary goal of a security program is to minimize risks that the public purse may have to cover the reclamation costs, which are likely to reach decades into the future. While opportunities exist for the regulator to demand additional security under the MSFP, these policy options have seen minimal utilization. Finally, both the long and near-term cost of liabilities associated with these projects remain quite uncertainty, with policy options for tailings and tailings water still in flux and under consideration, both provincially and federally. It is imperative that an open and public accounting for current and future liabilities be conducted, to ensure that security is sufficient to uphold the polluter pays principle and ensure that Albertans do not end up paying for the tailings management.[54] As the previous Oil Sands Environmental Coalition put it, “[w]ithout understanding the cost implications of Suncor’s TMP, the regulator cannot knowledgeably weigh the various tradeoffs” and neither can Albertans.[55]
Objectives of the TMF for progressive reclamation are laudable; however, it appears that practical barriers to significant gains in this area continue to thwart industry’s performance in this regard. Final answers remain elusive for long term tailings management and reclamation and as such this translates into foundational questions around sufficiency of security to ensure the environment is restored, monitored, and protected. As we acknowledged in Part One, reclamation of the tailings ponds will be a massive and multi-pronged job and any uncertainty in the implementation of existing frameworks only serves to worsen the problem.
Cover Photo by Howl Arts Collective, “tar sands, Alberta” (2008), via Flickr, licensed under CC BY 2.0.
Link to source: File:Tar sands in alberta 2008.jpg – Wikimedia Commons
Link to license: https://creativecommons.org/licenses/by/2.0/
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[1] Alberta Energy Regulator, Directive 085: Fluid Tailings Management for Oil Sands Mining Projects (2022) <https://static.aer.ca/prd/documents/directives/Directive085.pdf> [D-085]; Alberta Energy Regulator, Manual 024: Guide to the Mine Financial Security Program (2025) <https://static.aer.ca/prd/documents/manuals/Manual024.pdf> [M-024]; Government of Alberta, Lower Athabasca Region: Tailings Management Framework for the Mineable Athabasca Oil Sands (2015) <https://open.alberta.ca/publications/9781460121740#detailed> [TMF].
[2] Environmental Resources Conservation Board, Decision 60-06 (1960) online (record): https://had.aer.ca/link/decision2433.
[3] Suncor, “Base Plant Operations” (No Date, accessed 24 July 2025) online: <https://www.suncor.com/en-ca/what-we-do/oil-sands/base-plant-operations> [Suncor Base Plant].
[4] Suncor Base Plant.
[5] Alberta Energy Regulator, Decision 20171025A: Suncor Energy Inc., Applications for Millennium Operational Amendment and Base Plant Tailings Management Plan (October 25, 2017) <https://static.aer.ca/prd/documents/decisions/2017/20171025A.pdf> at v [Base Plant TMP].
[6] D-085 at 26
[7] Defined in D-085 as “fluid tailings in storage before January 1, 2015 (at 37).
[8] Defined in D-085 as “fluid tailings created on or after January 1, 2015 (at 37).
[9] D-085 at 5.
[10] Base Plant TMP at v.
[11] Alberta Energy Regulator, State of Fluid Tailings Management for Mineable Oil Sands, 2023 (October 2024) <https://static.aer.ca/prd/documents/reports/State-Fluid-Tailings-Management-Mineable-OilSands.pdf> at 22 [State of Fluid Tailings 2023]; Suncor Energy Inc., 2024 Base Plant Fluid Tailings Management Report (April 30, 2025) online: <https://www.aer.ca/data-and-performance-reports/industry-performance#tailings> at 4 (Figure 2-3) [Suncor FTMR 2024].
[12] Suncor, “Base Mine Extension (proposed)” online: https://www.suncor.com/en-ca/what-we-do/oil-sands/base-mine-extension.
[13] Letter from Jodi McNeill of Oil Sands Environmental Coalition to Alberta Energy Regulator Authorizations Review and Coordination Team (28 Jul 2017) re: “Re: Enhanced Review Process Suncor Energy Inc. Application Nos. 1857270, 1857274 and 075-94” at 5 online: https://www.pembina.org/reports/osec-final-comments-suncor-erp.pdf [McNeill].
[14] Base Plant TMP at para 1.
[15] Defined in D-085 as “the forecasted accumulation and reduction of fluid tailings volumes for each year to end of mine life” (at 37).
[16] Base Plant TMP at paras 70-72.
[17] Base Plant TMP at paras 71-72.
[18] Base Plant TMP at para 70.
[19] State of Fluid Tailings 2023 at 19.
[20] State of Fluid Tailings 2023 at 22.
[21] Suncor FTMR 2024 at 3.
[22] Suncor FTMR 2024 at 3.
[23] Suncor FTMR 2024 at 4 (Figure 2-3), 5 (Table 3-1).
[24] Suncor FTMR 2024 at 5 (Table 3-1).
[25] Suncor FTMR at 4 (Figure 2-3).
[26] TMF at 19.
[27] TMF at 19.
[28] TMF at 20.
[29] McNeill at 6.
[30] A fluid tailings reclamation technology, where the treatment of tailings is approached in phases. The fluid tailings are treated with a coagulant and a flocculant and are then placed in a storage area. Once all fluid tailings are stored, the storage pit is capped with water, to create an enclosure, with the end goal of returning water under natural flow and creating an end pit lake. Base Plant TMP at 25.
[31] Suncor FTMR 2024 at 3.
[32] Alberta Energy Regulator, Decision 20190225A: Fort Hills Energy Corporation; Application for Fort Hills Tailings Management Plan (February 25, 2019) <https://static.aer.ca/prd/documents/decisions/2019/20190225A.pdf> at para 15.
[33] Water capping is the placement of water above tailings (treated or non-treated) to create a pit lake as a reclaimed landscape feature. The use of water capping for the reclamation of tailings is currently not approved by the AER. State of Fluid Tailings 2023 at 69.
[34] Base Plant TMP at paras 135-137.
[35] Base Plant TMP at paras 133-135, 137; Suncor FTMR at 103; State of Fluid Tailings 2023 at 69.
[36] D-085 at s 4.6.
[37] Alberta Energy Regulator, Annual Mine Financial Security Program Submissions – 2024 Submissions for 2023 Reporting Year (2024) <https://static.aer.ca/prd/documents/liability/AnnualMFSPSubmissions.pdf> at 1 [MFSP 2024].
[38] MFSP 2024 at 1.
[39] Martin Olszynski, Andrew Leach, and Drew Yewchuk, “Not Fit for Purpose: Alberta’s Mine Financial Security Program” (2023) 16:36 University of Calgary School of Public Policy Research Paper at 6 [Olszynski et al.].
[40] Olszynski et al. at 6.
[41] Olszynski et al. at 6.
[42] M-024 at 1; McNeill at 9.
[43] Suncor Energy Inc., Annual Information Form 2024 (February 26, 2025) online: <https://www.suncor.com/-/media/project/suncor/files/investor-centre/annual-report-2024/2024-aif-en.pdf?modified=20250310191501&created=20250225185628> [Suncor Annual Information Form 2024]. Note that this includes all Suncor operations, not just the Base Plant operation.
[44] Sharon J. Riley, “Alberta ‘Undermining’ System Meant to Ensure Oilsands Companies Pay for Cleanup, Critics Say” (May 18, 2021) The Narwhal <https://thenarwhal.ca/alberta-oilsands-security-deposit-changes-critics/>; Olszynski et al. at 12.
[45] Unlike the BSD, which must be collected for all mines, and the OLD, which must be collected unless offset by the BSD.
[46] Suncor Annual Information Form 2024 at 33.
[47] Auditor General of Alberta, ”Environment and Parks and the Alberta Energy Regulator — Systems to Ensure Sufficient Financial Security for Land Disturbances from Mining” (2015) Report of the Auditor General of Alberta at 30 <https://www.oag.ab.ca/wp-content/uploads/2020/05/EP_PA_July2015_AER_Systems_Ensure_Fin_Security_Land_Disturb.pdf> [Auditor General of Alberta]; Olszynski et al. at 14.
[48] Auditor General of Alberta at 30; Olszynski et al. at 14.
[49] Alberta Energy Regulator, Annual Mine Financial Security Program Submissions – 2024 Submissions for 2023 Reporting Year (2024) at 1online: https://static.aer.ca/prd/documents/liability/AnnualMFSPSubmissions.pdf.
[50] M-024 at 21.
[51] M-024 at 21.
[52] Gillian Chow-Fraser and Alienor Rougeot, “50 Years of Sprawling Tailings: Mapping Decades of Destruction by Oil Sands Tailings” (2020) CPAWS Northern Alberta and Environmental Defence Canada <https://cpawsnab.org/our-work/oil-sands-tailings/> at 42; Olszynski et al. at 7.
[53] Olszynski et al. at 7.
[54] McNeill at 9.
[55] McNeill at 9.