Showing posts with label Nuclear Power Plants. Show all posts
Showing posts with label Nuclear Power Plants. Show all posts

Friday, 10 April 2020

Wildfire burning in the Chernobyl Exclusion Zone causes radiation levels to spike.

A forest fire burning in the exclusion zone around the former Chernobyl Nuclear Power Plant in Ukraine has caused local radiation levels to spike, according to the Ukrainian Ecological Inspection Service. The fire, which has burned about a square kilometre of forest and peat bog near the abandoned village of Vladimirovka, and which is thought to have been deliberately started, is reported to have caused ambient radiation levels in the area to rise from a typical average level of 0.14 microsieverts  per hour to about 2.30 microsieverts per hour. This is still only about a quarter of the level at which exposure becomes slightly dangerous, but a 1600% increase in a short period of time is cause for concern, and it is indicative of radioactive material formerly bound on soil and/or plant tissue being released into the atmosphere and redistributed. Smoke from the fire has been seen travelling about 100 km to the south, prompting Ukrainian police to evacuate about 200 people who had returned to the town of Poliske.

A forest fire burning near the abandoned village of Vladimirovka in the Chernobyl Exclusion Zone on 5 April 2020. Yaroslav Emelianenko/AFP/Getty Images.

The Chernobyl Exclusion Zone was established in 1985 following a fire at the former Chernobyl Nuclear Power Plant, which caused 43 deaths at the time, and is thought to have been responsible for about a hundred since. around 120 000 people were permanently evacuated from the zone, which has a radius of 30 km, centred on the site of the former power plant (part of this extends into neighbouring Belarus, where it is known as the Polesie State Radioecological Reserve. Ambient radiation levels in much of the zone today are not significantly higher than would be encountered living on a granite soil, but there remains concerns about radioactive material being redistributed by any large scale Human activity. As such the area has effectively become one of the largest nature reserves in Europe, with a large number of species, including large Mammals, recolonising the area.

Smoke plumes from a fire burning in the Chernobyl Exclusion Zone on 9 April 2020. As imaged by the MODIS instrument on the Aqua Satellite. NASA/Visible Earth.

See also...

https://sciencythoughts.blogspot.com/2019/12/huge-swarms-of-moon-jellyfish-seen-in.htmlhttps://sciencythoughts.blogspot.com/2015/03/at-least-33-dead-following-donetsk-mine.html
https://sciencythoughts.blogspot.com/2014/09/six-killed-as-car-falls-into-sinkhole.htmlhttps://sciencythoughts.blogspot.com/2014/06/seven-dead-and-two-missing-following.html
https://sciencythoughts.blogspot.com/2014/04/seven-workers-killed-by-explosion-at.htmlhttps://sciencythoughts.blogspot.com/2013/11/the-ten-most-polluted-places-on-earth.html
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Thursday, 24 October 2019

Closure of nuclear power plant allows Sea Nettles to return to New Jersey bay.

Sea Nettles,  have returned to Barnegat Bay in New Jersey following the closure of the Oyster Creek Nuclear Power Station in September 2018. The bay had a thriving ecosystem including a diverse invertebrate fauna before the opening of the power plant in 1969, but this was disrupted by the operations of the plant, which discharged water into the bay at 10°C above the normal temperature in the bay, disrupting the bay's normal wildlife. Since the power plant's closure the amount of water passing through it has been cut by 95%, and environmentalists are hoping that the return of the Sea Nettles will be a precursor to that of other species formerly common in the bay. The power plant was closed after the New Jersey Department of Environmental Protection agreed with concerns raised by environmental groups, who observed that the hot water was killing the eggs of a wide range of Fish and invertebrate groups, and that the system was sucking in vulnerable species, including Fish and Turtles, which were either trapped by the systems suction grates or pulled through the cooling pipes and killed by the heat within the reactors. A proposed alternative plan, that involved installing an air cooling system, was rejected by the plant's owners Excelon as being too costly. 

The former Oyster Creek Nuclear Power Station on Barnegat Bay in New Jersey. nj.com

Atlantic Sea Nettles, Chrysaora quinquecirrha, are a Jellyfish species reaching a maximum size of about 40 cm, which feed principally on zooplankton, making them a useful environmental indicator. The species is found on the Atlantic Coast of the Americas from New England to Brazil. The sting of a Sea Nettle, while unpleasant, is not a serious threat to Humans, usually causing a painful rash that persists for about 20 minutes.

An Atlantic Sea Nettles, Chrysaora quinquecirrha. Flower Garden Banks National Marine Sanctuary/NOAA/Wikimedia Commons.

See also...

https://sciencythoughts.blogspot.com/2019/10/millions-of-moon-jellyfish-seen-in.htmlhttps://sciencythoughts.blogspot.com/2019/01/mercury-and-selenium-levels-in.html
http://sciencythoughts.blogspot.com/2019/01/melicertissa-antrichardsoni-paralovenia.htmlhttp://sciencythoughts.blogspot.com/2018/12/carukia-barnesi-irukandji-jellyfish.html
http://sciencythoughts.blogspot.com/2018/12/chrysaora-spp-thousands-of-compass.htmlhttp://sciencythoughts.blogspot.com/2018/06/warning-issued-after-bloom-of-lions.html
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Friday, 8 November 2013

The ten most polluted places on Earth.

Each year since 2006 two environmental groups, the US based Blacksmith Institute and Green Cross Switzerland have produced an annual report into some of the world's most polluted places. This year's report, titled The World's Worst 2013: The Top Ten Toxic Threats, highlights ten sites across the world, deemed to be the worst polluted sites in their own right or noteworthy examples of types of polluted sites occurring at multiple locations. 

Sites included in the 2013 report. Blacksmith Institute & Green Cross Switzerland (2013).

The Agbogbloshie Dumpsite in Accra, Ghana is the second largest electronic waste recycling area in West Africa, handling much of the 215 000 tons of electronic waste Ghana imports each year as well as  the 129 000 tons produced domestically. Used electronic items are either reconditioned and resold or broken down for their metal content. A wide range of electronic items a handled, requiring a wide range of skills and techniques, and leading to the generation of a range of waste. Of particular concern is the recycling of copper from wiring, which is typically achieved by burning off the plastic sheathing, often using styrofoam packaging as a fuel. This produces toxic fumes from both the burning of the styrofoam and plastic, and from metal particles in the smoke. The site suffers from very high levels of soil contamination, with high levels of lead and other metals, affecting somewhere between 40 000 and 250 000 people living on and around the site. The Blacksmith Institute and Green Advocacy Ghana are working to introduce mechanized wire striping processes to the site.

Children on the Agbogbloshie Dumpsite. Blacksmith Institute & Green Cross Switzerland (2013).

Chernobyl in the Ukraine is recognized as the site of one of the worst nuclear disasters in history. In April 1986 the Chernobyl Nuclear Power Station suffered a massive meltdown, releasing more than 100 times as much radiation as the Hiroshima and Nagasaki bombs. A 30 km exclusion zone still exists around the site of the former power plant, and the reactor was encased in a concrete casing. However this casing was only intended as a temporary measure, and is known to be leaking in a number of places. The ground surrounding the site is also known to be contaminated with radionuclides such as cesium-137, which could potentially migrate to food crops grown in adjacent areas. Work has recently begun by the French company Novarka to build a steal containment structure around the original concrete casing, which should provide increased protection for the next 100 years. 

Memorial at the site of the Chernobyl Nuclear Power Station. Blacksmith Institute & Green Cross Switzerland (2013).

The Citarum River Basin in West Java covers around 13 000 km² and provides around 80% of the water needs of Jakarta. The area is home to around 9 million people, and produces around 5% of Indonesia's rice. It is also home to around 2000 factories. The waters of the basin are known to be heavily contaminated with aluminum, manganese, iron and other metals. The Indonesian Government  is working on a major rehabilitation and restoration project for the basin, financed by US$500 billion in loans from the Asian Development Bank.

Pollution on the Citarum River near Jakarta. Coastal Care.

The city of Dzerzhinsk, about 400 km east of Moscow, is a major center in the Russian chemical industry, and during the Cold War was also a center of manufacturing for chemical weapons.It is thought that between 1930 and 1998 around 300 000 tons of chemical waste were landfilled in and around Dzerhinsk, resulting in a wide variety of toxic chemicals being released into groundwater. The city has a population of about 245 000 people, with life expectancies of 42 for men and 47 for women. Since 2007 the Dzerzhinsk has been listed in the Guinness Book of Records as the world's most polluted city. As yet little has been done to rectify this situation, although the Russian government has announced plans to close outdated facilities and clean up contaminated land left from the Soviet era.

The location of Dzerzhinsk. Google Maps.

Hazaribagh in Bangladesh is home to 90% of the countries tanneries (leather processing plants), together employing between 9000 and 12 000 people out of a population of around 185 000 (though this is probably an underestimate, due to a number of informal settlements in the area). They also produce around 22 000 liters of toxic waste per day, including significant quantities of hexavalent chromium, which can lead to a variety of skin and respiratory diseases as well as being highly carcinogenic. Residents are also frequently prone to acid burns from tannery runoff, as well as the effects of a variety of fumes.

Residents of Hazaribagh live along side high levels of pollution including hexavalent chromium. Blacksmith Institute & Green Cross Switzerland (2013).

Kabwe is the second largest city in Zambia and was a center of (largely unregulated) lead mining and smelting from 1902 till the mid-1990s. There is still significant artisanal lead mining (informal, unregulated mining seldom featuring any form of heath and safety procedures), much of it on the spoil heaps of the former mine sites. The whole city suffers from high levels of lead pollution, principally in the from of lead dust, which is found in soils across the entire area. Testing has shown significant levels of lead in the blood of the population, particularly in that of children, who are more at risk from lead dust in soils as they play close to the ground. The Zambian Government has undertook a US$26 million remediation project in the area from 2003-2011, funded by the World Bank and Nordic Development Fund, but significant pollution problems remain.

Artisanal lead mining on a tailings dump at Kabwe in Zambia. Blacksmith Institute & Green Cross Switzerland (2013).

Kalimantan is the Indonesian portion of the island of Borneo and a significant center of artisanal gold mining. In the provinces of Central and South Kalimantan around 43 000 people are employed in the industry. The vast majority of these extract gold from ore using the mercury amalgam technique, which involves mixing ground up ore with mercury to extract the gold, then heating the resultant product ro burn off the mercury. It is estimated that Kalimantan produces around 1000 tons of mercury pollution per year, around a third of the global total. Mercury is extremely toxic and once vaporized can travel long distances as an areal pollutant. It is also particularly lethal in aquatic ecosystems, particularly as it accumulates in the bodies of fish which are then often consumed by humans, and has been found at high levels in the Kahayan River in Central Kalimantan. Indonesia signed the Minamata Convention on Mercury, which obliges it to limit mercury emissions, in October this year, and the Indonesian Government is working with the Blacksmith Institute, Yayasan Tambuhak Sinta and other NGOs to mitigate mercury release and exposure in the region.

An unregulated gold mine in Kalimantan. Philip Hatch-Barnwell

The Matanza-Riachuelo River Basin in Argentina hosts about 15 000 industrial sites, including many chemical plants, over a 60 km stretch of river, which cuts through part of the city of Buenos Aires. The level and type of pollution in the river fluctuates, but soils from the river bank have been shown to contain dangerously high levels of zinc, lead, copper, nickel, and chromium. Tests on well water from the river basin suggest that it should not be considered fit for human consumption and around 12 000 people are thought to be living in areas unsuitable for human habitation. There is little infrastructure in the area, and few options besides the drinking of well water. A US$ 1 billion project funded by the world bank aims to tackle sanitation and industrial pollutant abatement in the basin.

Residences by the Riachuelo River. The Argentina Independent.

The Niger Delta covers about 70 000 km² (roughly 8% of Nigeria's total landmass), and produces around 2 million barrels of crude oil per day, an industry that has existed in the area since the 1950s. An average of 240 000 barrels of oil are lost into the environment each year, creating massive levels of groundwater and soil pollution. This pollution is in itself highly toxic and leads to a variety of chronic health problems, but in the Niger Delta it is at such high levels that in many places agriculture and aquaculture (fish farming) have become impossible or severely curtailed, creating a food security crisis. Little of the wealth generated by the oil extraction process has reached the people of the Delta and there  are no realistic plans to remediate the ongoing crisis.

Oil pouring from a pipeline at Dadabili on the Niger Delta in April 2011. Afolabi Sotunde/Reuters.

The city of Norilsk in Russia was founded in 1935 as a Soviet slave labour camp, and has since grown into the second largest city in the Arctic Circle. The city is a major producer of heavy metals, using Soviet-era smelting technologies with almost no environmental protection. Around 130 000 residents are exposed to high levels of sulphur dioxide, copper and nickel pollution. The company responsible for the industrial sites, Norilsk Nickel, controls around 33% of the world's nickel supplies and is one of Russia's largest exporters of non-ferrous metals. Limited investments in reducing emissions have been made, but no attempts at remediating past pollution.

The Norilsk Nickel plant in Norilsk, in the Russian Arctic. George Washington University.

See also Two killed in escalating violence over mining in Davao del Sur Province, Mindanao, the PhilippinesProtests over environmental problems at Indian-owned Mozambique coal mineHuman Rights Watch reports on child labour in the Tanzanian gold mining industryThirty seven dead after collapse at gold mine in the Central African Republic and Amnesty International reports on the mining industry in Katanga Province, Democratic Republic of Congo.

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Thursday, 3 October 2013

Jellyfish force closure of Swedish nuclear power plant.

The Oskarshamn Nuclear Power Plant in Kalmar County on Sweden's southeast coast was forced to close one of its reactors on Sunday 29 October 2013, after a bloom of Jellyfish blocked one of its intake  pipes, preventing cold water from entering the turbine. The Oskarshamn Plant is a boiling water reactor, in which heat from the nuclear fuel is used to boil water, which then drives a steam turbine. The water is then cooled down by heat exchange with seawater that is pumped into the plant and then recycled. The intake which was blocked was used to bring in water for this cooling process, which is then returned to the sea; this water is never brought into direct contact with the nuclear fuel. This is essentially the same type of nuclear reactor as the  Fukushima Daiichi Plant in Japan, which was destroyed by a tsunami in 2011, though the Oskarshamn Plant is in a rather more stable geological setting.

The Oskarshamn Nuclear Power Plant. Wikimedia Commons.

This is not the first time that Oskarshamn has been closed down by a Jellyfish bloom, it was previously forced to close one of its reactors for similar reasons in 2005. Other reactors dependent on external water for cooling have suffered similar problems, for example the Diablo Canyon Power Plant in California was forced to close a reactor in 2012 due to a bloom of Salps (gelatinous macroplankton superficially resembling Jellyfish, but more closely related to Vertebrates) blocked its intake pipes and a number of hydroelectric and nuclear plants with freshwater intakes in the US have been forced to make repeated shutdowns due to pipes being blocked by the invasive Zebra Mussel (Dreissena polymorpha).

Jellyfish blooms have been linked to overfishing and marine pollution, which eliminate potential predators of Jellyfish allowing their numbers to explode. While this is undoubtably a factor in these events, Jellyfish do reproduce extremely rapidly under the correct conditions, and explosive population blooms are a part of their natural population cycle, so it is unlikely that such incidents could ever be completely eliminated.

The approximate location of the Oskarshamn Nuclear Power Plant. Google Maps.

The Oskarsham Reactor reopened on Tuesday 1 October, after several tonnes of Jellyfish had been removed from its intake pipes.