Oil sands tailings ponds (Canada)

In Canada there are three major oil sand deposits, primarily located in the province of Alberta, with some also located in the neighbouring province of Saskatchewan. They are known as Athabasca Oil Sands, Cold Lake oil sands, and Peace River oil sands. The Athabasca Oil Sands Region (AOSR) has 19 tailings ponds. == Components of oil sands tailings ponds ==

Oil sand tailings or oil sands process-affected water (OSPW), have a highly variable composition and a complex mixture of compounds. In his oft-cited 2008 journal article, E. W. Allen wrote that typically tailings ponds consist of c. 75% water, c. 25% sand, silt and clay, c.2% of residual bitumen, as well as dissolved salts, organics, and minerals. Although many of the components of TPW "occur naturally in adjacent landscapes, the mining process increases their concentrations", The concentrations of chemicals are harmful to fish, and oil on the surface of the ponds is harmful to birds. The lack of knowledge and identification of individual compounds has become a major hindrance to the handling and monitoring of oil sands tailings. A better understanding of the chemical makeup, including naphthenic acids, it may make it possible to monitor rivers for leachate and also to remove toxic components. The identification of individual acids has for many years proved to be impossible but a breakthrough in 2011 in analysis began to reveal what is in the oil sands tailings ponds. Theoretically, as much as ninety percent of the water in the tailings could be reused for further oil extraction. == Size and scope ==

According to an October 2021 Alberta Energy Regulator (AER) report, in 2020 in spite of a decrease in oil production, oil sands tailings ponds grew another 90 million cubic meters in 2020 containing 1.36 billion cubic metres of fluids. This represents a surface comparable to "1.7 times the size of Vancouver". By 2009, as tailing ponds continued to proliferate and volumes of fluid tailings increased, the Energy Resources Conservation Board of Alberta issued Directive 074 to force oil companies to manage tailings based on aggressive criteria. According to a Calgary Herald article, by September 2017, the tailings ponds held c."1.2 trillion litres of contaminated water" and covered about . ==Cost of clean-up==

A 2018 joint investigation by the Toronto Star, Global News, National Observer, and four journalism schools—Concordia University, Ryerson University, University of Regina and University of British Columbia—revealed that the estimated liability for the clean up cost for "oilsands mining operations facilities" was about $130 billion. was undertaken by "the largest ever collaboration of journalists in Canada". The investigation revealed that the security collected from companies to cover the costs of shutting down and cleaning up mining sites including tailings ponds and pipelines was $1.4 billion; and the previous calculated liability was $27.80 billion. The clean-up of tailings ponds, which "have sprawled to cover an area the size of Kelowna", which is , represents a "significant part of the liability." Syncrude Tailings Dam The Syncrude Tailings Dam or Mildred Lake Settling Basin (MLSB) is an embankment dam that was, by volume of construction material, the largest earth structure in the world in 2001. It is located north of Fort McMurray, Alberta, Canada, at the northern end of the Mildred Lake lease owned by Syncrude Canada Ltd. The dam and the tailings artificial lake within it are constructed and maintained as part of ongoing operations by Syncrude in extracting oil from the Athabasca Oil Sands. Other tailings dams constructed and operated in the same area by Syncrude include the Southwest Sand Storage (SWSS), which is the third largest dam in the world by volume of construction material after the Tarbela Dam. The MLSB, which is the oldest tailings pond in the Athabasca Oil Sands Region (AOSR), was found in a 2018 report published in the Atmospheric Chemistry and Physics journal to be "responsible for the majority of tailings ponds emissions of methane." On 31 December 2018, Syncrude was fined $2.75 million after pleading guilty under the federal Migratory Birds Convention Act (MBCA) and Alberta's Environmental Protection and Enhancement Act in relation to the deaths of 31 great blue herons in August 2015 at the MLSB. At the time the MLSB inactive sump "was not covered by Syncrude's waterfowl protection plan to deter birds from landing at tailings areas". Syncrude's trial lawyer at that time, Robert White, had urged his client to challenge the guilty verdict. However COSIA argues that CNRL's Horizon External Tailings Facility (ETF) is a relatively young pond with a configuration that minimizes the "Pond Centre (PC) depositional environment". It has a "side hill" facility with a three-sided dyke impounding fluid against the natural ground that rises away from the containment dyke." ==Regulations and oversight==

From its establishment in January 2008, until it was disbanded in 2013, the Edmonton, Alberta-based Energy Resources Conservation Board (ERCB)—an independent, quasi-judicial agency of the Government of Alberta—regulated Alberta's energy resource industry, which included oils sands tailings ponds. Board members included engineers, geologists, technicians, economists, and other professionals. The ERCB was created to replace the Alberta Energy and Utilities Board (EUB) and the Alberta Utilities Commission. The ERCB's first major publication was the December 2008, Directive 073: Requirements for Inspection and Compliance of Oil Sands Mining and Processing Plant Operations in the Oil Sands Mining Area, which was based Oil Sands Conservation Act (OSCA), Oil Sands Conservation Regulation (OSCR), Informational Letter (IL) 96-07: EUB/AEP Memorandum of Understanding on the Regulation of Oil Sands Development, IL 94-19: Dam Safety Accord, Agreement Between Alberta Employment, Immigration and Industry and the Alberta Energy and Utilities Board Respecting the Coordination of Services for Coal and Oil Sands Mine Projects (EII/EUB MOU), requirements set out in approval conditions for each oil sands mining and processing plant scheme, operator's ERCB-approved S-23 production accounting manual, Interim Directive (ID) 2001-07: Operating Criteria: Resource Recovery Requirements for Oil Sands Mine and Processing Plants, ID 2001-03: Sulphur Recovery Guidelines for the Province of Alberta, and Directive 019: ERCB Compliance Assurance—Enforcement. In 2009, the ERCB published an industry wide directive—Directive 074—which was the first of its kind. Directive 074 set out the "industry-wide requirements for tailings management," requiring "operators to commit resources to research, develop, and implement fluid tailings reduction technologies and to commit to tailings management and progressive reclamation as operational priorities that are integrated with mine planning and bitumen production activities." In 2012, the Government of Alberta set up a Tailings Management Framework (TMF) to complement and expand Directive 074's policies to "ensure that fluid fine tailings are reclaimed as quickly as possible and that current inventories are reduced." The ERCB's 2013 "Tailings Management Framework for Mineable Oil Sands" "challenged a "key plank" of the Conservative provincial government, under Premier Alison Redford, who served from October 2011 until her resignation on 23 March 2014. During the tenure of the Redford cabinet, the province was promoting "Alberta as a responsible energy producer." The government had pledged that the "turbid tailings ponds containing the byproducts of bitumen production will soon be a thing of the past." In March 2015, in response to the ERCB's "Tailings Management Framework for Mineable Oil Sands", AER suspended Directive 074: Tailings Performance Criteria and Requirements for Oil Sands Mining Schemes. In May 2016, the Court of Queen's Bench of Alberta (ABQB) in 2016 ABQB 278, "confirmed that the federal Bankruptcy and Insolvency Act supersedes the provincial requirements that companies must clean up wells." "[B]ankrupt companies can avoid their liabilities and leave them as a public obligation." Directive 85 was issued on 14 July 2016, by the Alberta Energy Regulator, following consultations with "consultations with First Nations, local communities, environmental groups and industry itself". Directive 85 with new guidelines and a phased-in approach on oil sands producers' management of their tailings ponds. In July 2019, the AER announced their Decision 2019 ABAER 006: Syncrude Canada Ltd. Mildred Lake Extension Project and Mildred Lake Tailings Management Plan, with a 289-page report. Syncrude's had submitted their request regarding the Mineral Surface Lease MSL352 in 30 June 2017. The AER decision allows Syncrude to use more public lands to develop oil sands on oil sands leases 17 and 22, under section 20 of the Public Lands Act, with a number of conditions, related to relevant laws, including the Oil Sands Conservation Act (OSCA), the Environmental Protection and Enhancement Act (EPEA), the Water Act, and the Public Lands Act. AER on cost of clean-up of tailings ponds In an AER presentation in February 2018, the AER's "vice-president of closure and liability" said that "based on "a hypothetical worst-case scenario", the cleanup cost would be $260-billion based on "internal AER calculations". The oil industry's "accumulated environmental liability" estimate of $58.65 billion was the amount that the AER had publicly reported. On 15 February 2018 the Supreme Court of Canada held a hearing centering on Alberta's lower courts' findings in favour of Redwater Energy's creditors, to determine if Canada's bankruptcy laws are in conflict with Alberta's regulatory regime – and if those federal laws are paramount to the province's environmental rules". By February, 2018, there were 1,800 abandoned or orphan wells—sites that had been licensed by AER with combined liabilities of over $110 million. From 2014 to 2018 the industry-led organization's Orphan Well Association's (OWA) inventory, increased from 1,200 to over 3,700. In late February 2018, CBC News and CP reported that Sequoia Resources Ltd, an oil firm that had purchased "licences for 2,300 wells" in 2016 from Perpetual Energy Inc., had notified AER that it was ceasing operations "imminently" and were unable to maintain "almost 200 facilities and nearly 700 pipeline segments". On 7 August 2018 PricewaterhouseCoopers, the trustee for Chinese investors who purchased Sequoia Resources Ltd in 2016, launched a lawsuit against Perpetual Energy Inc. in an "unprecedented bid to void" the 2016 sale of Perpetual Energy Inc.'s subsidiary called Perpetual Energy Operating Corp. (PEOC) now known as Sequoia Resources Ltd to Chinese investors. An article in The Globe and Mail said that this appears to be the "first attempt by a bankruptcy trustee in Alberta to have a previous oil and gas transaction unwound." It could "introduce major new risks to the [oil and gas] industry's ability to buy and sell assets and could also deliver a severe blow to Perpetual." The lawsuit alleges that Perpetual and its CEO Susan Riddell Rose "knew the deal would sink the buyer". In a public statement released on 8 August 2018, AER CEO Jim Ellis, who had been CEO since AER's creation in 2013, took the "unusual step" On 1 November 2018 AER CEO Jim Ellis apologized for failing to report "that cleaning up after the province's oil and gas industry would cost $260 billion". On 2 November he announced his retirement as CE0. At Canadian federal government level, in May 2023, passing of Bill S-5 to update the Canadian Environmental Protection Act was reported as having slowed because of Liberal Party support for an amendment proposed by the New Democratic Party. The amendment stipulated that "... the federal government has the power to compel the production of information about tailings ponds". == Reduction and reclamation ==

The Alberta Energy Regulator has confirmed that no tailings have ever been certified reclaimed to date. In fact, across the entire oil sands region, only one square km of the total area disturbed by mining operations has ever been certified reclaimed. Suncor invested $1.2 billion in their Tailings Reduction Operations (TROTM) method that treats mature fine tails (MFT) from tailings ponds with chemical flocculant, an anionic Polyacrylamide, commonly used in water treatment plants to improve removal of total organic content (TOC), to speed their drying into more easily reclaimable matter. Mature tailings dredged from a pond bottom in suspension were mixed with a polymer flocculant and spread over a "beach" with a shallow grade where the tailings would dewater and dry under ambient conditions. The dried MFT can then be reclaimed in situ or moved to another location for final reclamation. Suncor hoped this would reduce the time for water reclamation from tailings to weeks rather than years, with the recovered water being recycled into the oil sands plant. Suncor claimed the mature fines tailings process would reduce the number of tailing ponds and shorten the time to reclaim a tailing pond from 40 years at present to 7–10 years, with land rehabilitation continuously following 7 to 10 years behind the mining operations. For the reporting periods from 2010 to 2012, Suncor had a lower-than-expected fines capture performance from this technology. This often-cited example of reclamation is challenged by environmental groups, who point out that the pond is not reclaimed, as the actual harmful tailings fluids were just moved somewhere else. Indeed, the pond's content was drained, and the tailings fluids were transported to other ponds. The pond was then filled with coarser materials and vegetation was added on top. The site is not usable or accessible to the public, and the peatland was not restored. Syncrude's Sandhill Fen project In 2008 Syncrude Canada Ltd. began construction of Sandhill Fen project, a 57-hectare research watershed- creating a mix of forest and wetland- on top of sand-capped composite tailings at its former 60-metre deep East Mine. End Pit Lakes The Pembina Institute suggested that the huge investments by many companies in Canadian oil sands was leading to increased production results in excess bitumen with no place to store it. It added that by 2022 a month's output of waste-water could result in an 11-feet deep toxic reservoir the size of New York City's Central Park [840.01 acres (339.94 ha) (3.399 km²)]. The oil sands industry may build a series of up to thirty lakes by pumping water into old mine pits when they have finished excavation leaving toxic effluent at their bottoms and letting biological processes restore it to health. It is less expensive to fill abandoned open pit mines with water instead of dirt. In 2012, the Cumulative Environmental Management Association (CEMA) defined End Pit Lakes (EPLs) as Syncrude Ltd. has a full-scale, operational EPL known as Base Mine Lake, which has been under reclamation since 2012. The addition of a water cap and alum successfully cleared the water of turbidity. Algae and invertebrates populate the water column, and the bacterial communities are distinct from those of tailings ponds. However, as an oil sheen does remain on the surface of the lake, Syncrude does not plan to connect this EPL with natural water bodies, or release any water from the site. == Research ==

In March 2012 an alliance of oil companies called Canada's Oil Sands Innovation Alliance (COSIA) was launched with a mandate to share research and technology to decrease the negative environmental impact of oil sands production focusing on tailings ponds, greenhouse gases, water and land. Almost all the water used to produce crude oil using steam methods of production ends up in tailings ponds. Recent enhancements to this method include Tailings Oil Recovery (TOR) units which recover oil from the tailings, Diluent Recovery Units to recover naphtha from the froth, Inclined Plate Settlers (IPS) and disc centrifuges. These allow the extraction plants to recover well over 90% of the bitumen in the sand. In January 2013, scientists from Queen's University published a report analyzing lake sediments in the Athabasca region over the past fifty years. They found that levels of polycyclic aromatic hydrocarbons (PAHs) had increased as much as 23-fold since bitumen extraction began in the 1960s. Levels of carcinogenic, mutagenic, and teratogenic PAHs were substantially higher than guidelines for lake sedimentation set by the Canadian Council of Ministers of the Environment in 1999. The team discovered that the contamination spread farther than previously thought. For metal concentrations, some studies of metal contaminants in Peace-Athabasca Delta lake sediments in 2014 to 2018 showed "... little to no evidence of recent oil sands-derived metals enrichment in sediment of lakes" in the region. ==Emissions ==

According to the 2018 study by Baray et al, ninety-six per cent of methane emissions in the AOSR came from Mildred Lake Settling Basin and the Syncrude Mildred Lake West In-Pit (WIP) pond and Suncor Energy OSG's Ponds 2–3 (P23). MLSB "was found to be responsible for over 70% of tailings ponds emissions of methane (CH4)." The study collected data on emission rates of CH4 from the "five major facilities in the AOSR: Syncrude Mildred Lake (SML), Suncor Energy OSG (SUN), Canadian Natural Resources Limited Horizon (CNRL), Shell Albian Muskeg River and Jackpine (SAJ) and Syncrude Aurora (SAU)." 2018 report published in the Atmospheric Chemistry and Physics journal to be "responsible for the majority of tailings ponds emissions of methane." == See also ==