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48-472: A $ 6.2 billion deal between Newfoundland and Labrador's Nalcor Energy and Halifax, Nova Scotia-based Emera to develop the project was announced in November 2010. On November 30, 2012, a federal loan guarantee deal for financing of the project was signed by Prime Minister Stephen Harper , Newfoundland and Labrador Premier Kathy Dunderdale and Nova Scotia Premier Darrell Dexter . On December 17, 2012,

96-554: A half-life in human blood of about 50 days. Several studies indicate that methylmercury is linked to subtle developmental deficits in children exposed in utero such as loss of IQ points, and decreased performance in tests of language skills, memory function and attention deficits. Methylmercury exposure in adults has also been linked to increased risk of cardiovascular disease including heart attack . Some evidence also suggests that methylmercury can cause autoimmune effects in sensitive individuals. Despite some concerns about

144-450: A given species of fish, older and larger fish have higher levels of methylmercury than smaller fish. Fish that develop in water bodies that are more acidic also tend to have higher levels of methylmercury. Ingested methylmercury is readily and completely absorbed by the gastrointestinal tract . It is mostly found complexed with free cysteine and with proteins and peptides containing that amino acid. The methylmercuric-cysteinyl complex

192-830: A good source of nutrition and has significant health benefits, but that consumers, in particular pregnant women, women of child-bearing age, nursing mothers, and young children, should avoid fish with high levels of methylmercury, limit their intake of fish with moderate levels of methylmercury, and consume fish with low levels of methylmercury no more than twice a week. In recent years, there has been increasing recognition that methylmercury affects fish and wildlife health, both in acutely polluted ecosystems and ecosystems with modest methylmercury levels. Two reviews document numerous studies of diminished reproductive success of fish, fish-eating birds, and mammals due to methylmercury contamination in aquatic ecosystems. Reported methylmercury levels in fish, along with fish consumption advisories, have

240-479: A proposed 563 km underwater transmission line from New Brunswick to Massachusetts . In late 2006, Nalcor registered the generation components of the Lower Churchill Project, including both Gull Island and Muskrat Falls, for environmental assessment with the provincial and federal governments. The provincial and federal government agreed to a combined review process that would fulfill

288-476: A result of mercury released from the mercury-cell Chloralkali process , which uses liquid mercury as an electrode in a process that entails electrolytic decomposition of brine, followed by mercury methylation in the aquatic environment. An acute methylmercury poisoning tragedy occurred also in Minamata, Japan , following release of methylmercury into Minamata Bay and its tributaries (see Minamata disease ). In

336-662: A small area of wetland near the reservoir – but the permit was never approved by the Department of Municipal Affairs and Environment. Premier Dwight Ball later said wetland capping would have only decreased methylmercury levels by two per cent. The project is more than $ 6 billion over budget, and five years late as of 2022. Projected cost overruns exceeding 70% from $ 7.4 billion to $ 12.7 billion due to poor planning, lack of engineering experience, and related assumptions that were invalid, misleading or later turned out to be incorrect led Nalcor CEO Stan Marshall to say that

384-403: A subsidiary of Nalcor. Newfoundland and Labrador Hydro , commonly shortened to "Hydro", was originally a subsidiary of Nalcor, generating and delivering electricity for Newfoundland and Labrador , as well as parts of Quebec and the north-eastern United States . It also delivers voice and data telecommunications services to customers in some areas. Hydro itself is the parent company of

432-405: Is an organometallic cation with the formula [CH 3 Hg] . It is the simplest organomercury compound. Methylmercury is extremely toxic, and its derivatives are the major source of organic mercury for humans. It is a bioaccumulative environmental toxicant with a 50-day half-life . Methylmercury is the causative agent of the infamous Minamata disease . "Methylmercury" is a shorthand for

480-523: Is currently focused on more subtle effects that may be linked to levels of exposure presently seen in populations with high to moderate levels of dietary fish consumption. These effects are not necessarily identifiable on an individual level or may not be uniquely recognizable as due to methylmercury. However, such effects may be detected by comparing populations with different levels of exposure. There are isolated reports of various clinical health effects in individuals who consume large amounts of fish; however,

528-779: Is formed from inorganic mercury by the action of microbes that live in aquatic systems including lakes , rivers , wetlands , sediments , soils and the open ocean . This methylmercury production has been primarily attributed to anaerobic bacteria in the sediment. Capable bacteria that can methylate mercury are mostly the sulfate-reducing bacteria (SRB), iron-reducing bacteria (FeRB) and methanogens . Significant concentrations of methylmercury in ocean water columns are strongly associated with nutrients and organic matter remineralization , which indicate that remineralization may contribute to methylmercury production. Direct measurements of methylmercury production using stable mercury isotopes have also been observed in marine waters, but

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576-597: Is only a trace constituent of such fuels, their large scale combustion in utility and commercial/industrial boilers in the United States alone results in release of some 80.2 tons (73 metric tons ) of elemental mercury to the atmosphere each year, out of total anthropogenic mercury emissions in the United States of 158 tons (144 metric tons)/year. In the past, methylmercury was produced directly and indirectly as part of several industrial processes such as

624-423: Is recognized by amino acids transporting proteins in the body as methionine , another essential amino acid . Because of this mimicry, it is transported freely throughout the body including across the blood–brain barrier and across the placenta , where it is absorbed by the developing fetus . Also for this reason as well as its strong binding to proteins, methylmercury is not readily eliminated. Methylmercury has

672-546: Is transmitted from Stephenville on Newfoundland to Nova Scotia via a 200 kV 180 km sub-sea line to Point Aconi on Cape Breton Island with a capacity of 500 MW. Construction was a 1.2 billion dollar joint venture between Nalcor and Emera . The link came online in December 2017. Once on Newfoundland and the mainland of the Maritimes , power is distributed via the existing grid. Emera hopes to sell surplus power via

720-566: The Government of Canada would provide the project with $ 5.2 billion of financial support to compensate for its large cost overrun (from $ 6.2 billion to over $ 13 billion) and to enable the province to maintain the price of power at a competitive rate (14.7 cents per kilowatt-hour). The government of Quebec and Bloc Québécois Members of Parliament protested against this subsidy, which they claimed provided unfair competition to their own Hydro Québec power company . The Innu Nation protested

768-654: The Government of Newfoundland and Labrador , Nalcor Energy was created in 2007 to manage the province's energy resources. The company had distinct business lines comprising Newfoundland and Labrador Hydro , the Churchill Falls Generating Station , the Lower Churchill Project , energy marketing, oil and gas development, and The Bull Arm Fabrication Site . On June 23, 2021, Premier Andrew Furey announced Nalcor Energy would be dismantled and folded into NL Hydro, previously

816-741: The Newfoundland and Labrador onshore and offshore oil developments. The company is currently a partner in three offshore developments - the Hebron oil field, the White Rose Growth Project and the Hibernia Southern Extension . A $ 20 million onshore drilling exploration program in Parsons Pond in western Newfoundland is also being operated by Nalcor - Oil and Gas. The Bull Arm Fabrication site

864-481: The 101 km reservoir. Containment is by a two-part concrete dam totalling 757 metres long. This will power an 834 MW generating station. Power is transmitted to Newfoundland via a 350 kV high-voltage direct current line with a capacity of 900 MW. The total length is 1,100 km, of which 30 km are submarine power cables under the Strait of Belle Isle . Construction began in 2014 and ended in 2018. Power

912-642: The Hydro Group of Companies, which comprises: The Churchill Falls Generating Station is one of the largest underground powerhouses in the world. The plant has 11 turbines with a rated capacity of 5,428 megawatts. Nalcor controlled a 65.8% share of the Churchill Falls Labrador Corporation Limited , the owner of the Churchill Falls station while Quebec's government-owned utility , Hydro-Québec , owns

960-600: The Ontario case, inorganic mercury discharged into the environment was methylated in the environment; whereas, in Minamata, Japan, there was direct industrial discharge of methylmercury. Because methylmercury is formed in aquatic systems, and because it is not readily eliminated from organisms, it is biomagnified in aquatic food chains from bacteria , to plankton , through macroinvertebrates , to herbivorous fish and to piscivorous (fish-eating) fish. At each step in

1008-470: The United Nations Food and Agriculture Organization (FAO), have issued guidance for fish consumers that is designed to limit methylmercury exposure from fish consumption. At present, most of this guidance is based on protection of the developing fetus; future guidance, however, may also address cardiovascular risk. In general, fish consumption advice attempts to convey the message that fish is

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1056-434: The completion of the final successful test of the 1100 km transmission link to Newfoundland. Commissioning by the federal government will be announced following the completion of paperwork. Originally approved in 2012 with an anticipated price tag of around $ 7.4 billion, the costs of the project increased to more than $ 13 billion. Reservoir impoundment was completed in 2019 with the flooding of 41 km of land to create

1104-518: The decision stating they had not been consulted. The Innu Nation also raised concerns about the compensation claimed by the Innu and how cost overruns may reduce the amount of Innu royalties received under the 2011 impact and benefits agreement. Nalcor Energy Nalcor Energy was an energy corporation which headquartered in St. John's , Newfoundland and Labrador . A provincial Crown corporation under

1152-411: The distributed mercury depositional input is from current anthropogenic sources, and 70% is from natural sources. The natural sources category includes re-emission of mercury previously deposited from anthropogenic sources. According to one study, based on modeled concentrations, pre- Anthropocene tissue-bound levels in freshwater fish may not have differed markedly from current levels. However, based on

1200-558: The dumping of industrial waste that resulted in the pollution and subsequent mass poisoning in Minamata and Niigata , Japan and the situation in Iraq in the 1960s and 1970s in which wheat treated with methylmercury as a preservative and intended as seed grain was fed to animals and directly consumed by people (see Basra poison grain disaster ). These episodes resulted in neurological symptoms including paresthesias , loss of physical coordination, difficulty in speech , narrowing of

1248-462: The establishment of an independent committee to make recommendations on mitigating potential impacts of methylmercury on human health from the Lower Churchill Project at Muskrat Falls, Labrador. In 2018, the committee recommended – among other things – wetland capping to stem the release of methylmercury . During the Muskrat Falls inquiry in 2019, it was revealed

1296-410: The fall of 2021. However, there were delays in construction, including on the corresponding Labrador–Island Link which will transmit generated power to a converter outside St. John's . On June 23, 2021, Premier Andrew Furey announced Nalcor Energy would be dismantled and folded into Newfoundland and Labrador Hydro . In April 2023, Jennifer Williams, CEO of Newfoundland and Labrador Hydro, announced

1344-528: The food chain, the concentration of methylmercury in the organism increases. The concentration of methylmercury in the top-level aquatic predators can reach a level a million times higher than the level in the water. This is because methylmercury has a half-life of about 72 days in aquatic organisms resulting in its bioaccumulation within these food chains. Organisms, including humans, fish-eating birds, and fish-eating mammals such as otters and cetaceans (i.e. whales and dolphins ) that consume fish from

1392-431: The hypothetical "methylmercury cation", sometimes written methylmercury(1+) cation or methylmercury(II) cation . This functional group is composed of a methyl group bonded to an atom of mercury . Its chemical formula is CH 3 Hg (sometimes written as MeHg ).The Methylmercury compound has an overall charge of +1, with Hg in the +2 oxidation state . Methylmercury exists as a substituent in many complexes of

1440-700: The manufacture of acetaldehyde . However, currently there are few direct anthropogenic sources of methylmercury pollution in the United States. Whole-lake ecosystem experiments at IISD-ELA in Ontario , Canada, showed that mercury falling directly on a lake had the fastest impacts on aquatic ecosystems as opposed to mercury falling on the surrounding land. This inorganic mercury is converted to methylmercury by bacteria. Different stable isotopes of mercury were added to lakes, wetlands , and uplands , simulating rain, and then mercury concentrations in fish were analyzed to find their source. The mercury applied to lakes

1488-493: The microbes involved are still unknown. Increased methylmercury concentrations in water and fish have been detected after flooding of soils associated with reservoir creation (e.g. for hydroelectric power generation ) and in thermokarst wetlands that form after permafrost thaw. The increased methylmercury concentration is due to its ability to bio-accumulate and biο-magnify in aquatic food webs. There are various sources of inorganic mercury that may indirectly contribute to

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1536-519: The potential to disrupt people's eating habits, fishing traditions, and the livelihoods of the people involved in the capture, distribution, and preparation of fish as a foodstuff for humans. Furthermore, proposed limits on mercury emissions have the potential to add costly pollution controls on coal-fired utility boilers. Nevertheless, substantial benefits can be achieved globally by introducing mercury emission reduction measures because they reduce human and wildlife exposure to methylmercury. About 30% of

1584-419: The production of methylmercury from microbes in the environment. Natural sources of mercury released to the atmosphere include volcanoes , forest fires , volatilization from the ocean and weathering of mercury-bearing rocks . Anthropogenic sources of mercury include the burning of wastes containing inorganic mercury and from the burning of fossil fuels , particularly coal . Although inorganic mercury

1632-418: The project was a boondoggle . In 2017, Premier Dwight Ball called a public inquiry into the project, which took place between 2018 and 2020. In the inquiry report, Commissioner Richard LeBlanc concluded the government failed its duty to residents by predetermining that the megaproject would proceed no matter what. In his report, LeBlanc concluded that the business case, which assumed the Muskrat Falls project

1680-650: The project was acceptable to them. In 2016, researchers from Harvard University suggested that methylmercury levels in fish would rise as a result of the project. After protests led by Indigenous groups in Central Labrador in 2016, an agreement was reached by Labrador’s three Indigenous groups ( Nunatsiavut Government, Innu Nation and the NunatuKavut Community Council) and the Government of Newfoundland and Labrador outlining

1728-600: The provincial government announced project sanction. Emera received approval to proceed with the Maritime Link from the Nova Scotia Utility and Review Board in 2013. Financial close for the loan guarantee occurred in late 2013. On September 23, 2020, the first unit at Muskrat Falls was synced to the electricity grid in Labrador. Power from the remaining three units was originally expected to come online in

1776-646: The provincial government began in 2006, resulting in the New Dawn (Tshash Petapen) Agreement, finalized in 2011. This agreement included an Impacts and Benefits Agreement (IBA), a Redress Agreement related to damage caused by the Churchill Falls development, and an agreement in principle about the Innu Nation’s land claim. Upon the ratification of the New Dawn Agreement, the Innu Nation indicated that

1824-553: The provincial government wouldn’t be completing wetland capping at the Muskrat Falls reservoir as previously planned. The $ 30 million designated for the capping was split up and offered to all three Indigenous governments, with the Innu Nation and NunatuKavut accepting. Nalcor had applied for a permit in July 2018 to carry out the approximately 13 hectares of wetland capping – essentially pouring sand and stone over

1872-718: The relationship between methylmercury exposure and autism, there are few data that support such a link. Although there is no doubt that methylmercury is toxic in several respects, including through exposure of the developing fetus, there is still some controversy as to the levels of methylmercury in the diet that can result in adverse effects. Recent evidence suggests that the developmental and cardiovascular toxicity of methylmercury may be mitigated by co-exposures to omega-3 fatty acids and perhaps selenium , both found in fish and elsewhere. There have been several episodes in which large numbers of people were severely poisoned by food contaminated with high levels of methylmercury, notably

1920-584: The remaining shares. The Lower Churchill Project is a planned project to develop the remaining 35% of the Churchill River , that has not already been developed by the Upper Churchill Falls Generating Station . The Lower Churchill's two installations at Gull Island and Muskrat Falls will have a combined capacity of over 3,000 MW. Nalcor Energy's Oil and Gas division held and managed oil and gas interests in

1968-408: The requirements of both levels of government, resulting in the formation of a Joint Review Panel. In 2010, the focus shifted to Muskrat Falls only. The environmental assessment for the transmission lines was done separately and was conducted in 2013. Many Indigenous peoples had serious concerns about how the land and wildlife would be changed by the development. Negotiations between the Innu Nation and

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2016-748: The specific health effects and exposure patterns have not been verified with larger, controlled studies. Many governmental agencies, the most notable ones being the United States Environmental Protection Agency (EPA), the United States Food and Drug Administration (FDA), Health Canada , and the European Union Health and Consumer Protection Directorate-General , as well as the World Health Organization (WHO) and

2064-647: The top of the aquatic food chain receive the methylmercury that has accumulated through this process, plus the toxins in their habitat. Fish and other aquatic species are the main source of human methylmercury exposure. The concentration of mercury in any given fish depends on the species of fish, the age and size of the fish and the type of water body in which it is found. In general, fish-eating fish such as shark , swordfish , marlin , larger species of tuna , walleye , largemouth bass , and northern pike , have higher levels of methylmercury than herbivorous fish or smaller fish such as tilapia and herring . Within

2112-455: The type [MeHgL] (L = Lewis base) and MeHgX (X = anion). As a positively charged ion, it readily combines with anions such as chloride ( Cl ), hydroxide ( OH ) and nitrate ( NO − 3 ). It has particular affinity for sulfur -containing anions, particularly thiols ( RS ). Thiols are generated when the amino acid cysteine and the peptide glutathione form strong complexes with methylmercury: Methylmercury

2160-406: The visual field , hearing impairment , blindness , and death. Children who had been exposed in utero through their mothers' ingestion were also affected with a range of symptoms including motor difficulties, sensory problems and intellectual disability . At present, exposures of this magnitude are rarely seen and are confined to isolated incidents. Accordingly, concern over methylmercury pollution

2208-611: Was developed in the early 1990s and is Atlantic Canada 's largest industrial fabrication site. The site is located 150 kilometers west of St. John's, Newfoundland and Labrador . The Hibernia oil field's gravity base structure was constructed at the site, as well work on the two Floating Production Storage and Offloading (FPSO) vessel's for the Terra Nova oil field and the White Rose oil field were done here. Methylmercury Methylmercury (sometimes methyl mercury )

2256-489: Was found in young-of-the-year yellow perch within two months, whereas the mercury applied to wetlands and uplands had a slower but longer influx. Acute methylmercury poisoning can occur either directly from the release of methylmercury into the environment or indirectly from the release of inorganic mercury that is subsequently methylated in the environment. For example, methylmercury poisoning occurred at Grassy Narrows in Ontario, Canada (see Ontario Minamata disease ), as

2304-457: Was the lowest-cost power option, was “questionable.” LeBlanc said that the project’s economics were not sufficiently tested and that Nalcor failed to consider all potentially viable power options. LeBlanc said that Nalcor concealed information that could have undermined the business case for the project from the public and government. In July 2021, Prime Minister Justin Trudeau announced that

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