Showing posts with label Nuclear energy. Show all posts
Showing posts with label Nuclear energy. Show all posts

Thursday, December 4, 2014

Brown bear photographed in Chernobyl exclusion zone, first verified sighting in a century



 On April 26, 1986, explosions and a fire at a nuclear facility near Chernobyl in the then Ukrainian Soviet Socialist Republic released large amounts of radiation into the atmosphere that drifted far into western USSR and other parts of Europe.
At the time of the disaster a pine forest just a ways downwind from the disaster turned red and died. Some animals in the nearby areas also died or stopped bearing young. Horses left on an island in a river about 4 miles from the disaster site died when their thyroid glands were destroyed by radiation. Some forms of life thrive in the radiation. A robot found black fungi on the walls of the destroyed reactor. Thirty-one people died from the accident itself but there were many long-term effects such as cancers and deformities. After the accident an exclusion zone was set up and people evacuated from the area: An area originally extending 30 kilometres (19 mi) in all directions from the plant is officially called the "zone of alienation". It is largely uninhabited, except for about 300 residents who have refused to leave. The area has largely reverted to forest, and has been overrun by wildlife because of a lack of competition with humans for space and resources.... Ukrainian officials estimate the area will not be safe for human life again for another 20,000 years. In 2011 the Ukraine opened up the zone to tourists.
Several scientific studies have shown that the radiation has had a negative effect on insects, birds, and mammals in the area but some experts disagree with the conclusions of the studies. A paper by Anders Moller of the University Pierre and Marie Curie in France and Tim Mousseau from the University of South Carolina said: "Recent conclusions from the UN Chernobyl Forum and reports in the popular media concerning the effects of radiation from Chernobyl has left the impression that the exclusion zone is a thriving ecosystem, filled with an increasing number of rare species. Species richness, abundance and population density of breeding birds decreased with increasing levels of radiation."
 Dr. Sergi Gashchak of the Chernobyl Center of the Ukraine told the BBC: "Wildlife really thrives in Chernobyl area - due to the low level of [human] influence. All life appeared and developed under the influence of radiation, so mechanisms of resistance and recovery evolved to survive in those conditions.". Professor Mousseau called Dr. Gashchak's evidence purely anecdotal whereas the paper he wrote with Moller provides quantitative and rigorous data that shows that mammals have been negatively affected by radiation. Even so Mousseau thought it a good idea to set up the area as a wildlife sanctuary that would allow scientists to do long term studies on the effects of radiation on wildlife.
 While Mousseau might be correct that overall species diversity may have declined in the Exclusion area evidence now shows that at least one species the brown bear has appeared in the area for the first time in 100 years. The Transfer, Exposure, Effects (TREE) project installed cameras that Dr. Gaschak found had a photograph of a brown bear (Ursus arctos). Mike Wood of the University of Salford told BBC that webcams clearly showed the bears. He said: "There have been suggestions that they existed there previously but, as far as we know, no-one has got photographic evidence of one being present on the Ukrainian side of the exclusion zone." Part of the exclusion zone is in Belarus.
The TREE project website says that the TREE project wants “to reduce uncertainty in estimating the risk to humans and wildlife associated with exposure to radioactivity and to reduce unnecessary conservatism in risk calculations. Our studies will combine controlled laboratory experiments with fieldwork; most of which will take place in the Chernobyl Exclusion Zone.” As the appended video shows, there are rare wild horses in the Exclusion zone, introduced there to see if they would survive. They have and their offspring showed no ill effects of radiation. However, the zone has a burgeoning population of wolves who kill some of the horses. Also, poor Ukrainians hunt the horses for meat. At last count the number of horses showed a slight decline but there is no evidence that radiation was a factor.

Sunday, April 8, 2007

Nuclear Energy Renaissance

Nuclear power seems to be coming back without any of the problems being solved with respect to how to dispose of the waste. There is also still the danger of accidents. It seems the long term dangers of the plants are ignored. Environmentalists seem to be concentrating on global warming and climate change and problems of nuclear energy are being left on the back burner.



Nuclear renaissance already here: consultant
Mon Apr 2, 2007 3:05PM EDT
WASHINGTON (Reuters) - The race to generate more electricity from nuclear power plants in the United States is officially underway, according to a report released on Monday.

Cambridge Energy Research Associates, private energy consultants, says that the promised U.S. "nuclear renaissance" is already happening, although not through the construction of new plants.

Mostly, companies are expanding existing reactors and extending licenses to operate, the report found.

In the United States, 48 reactors have recently been granted 20-year life extensions by the Nuclear Regulatory Commission, and the remaining 56 will likely be granted extensions soon, the group said.

The nation's 104 nuclear plants generate about 20 percent of U.S. electricity supplies, but the NRC has not issued a new plant license since 1973.

Financial incentives packed into an energy law passed in 2005, along with a move to diversify U.S. energy supply away from fossil fuels, is driving the trend, the group said.

A growing global acceptance of nuclear plants and solid performance in Asia and Europe has also boosted demand, CERA writes.

The Three Mile Island accident in Pennsylvania in 1979 and the Chernobyl disaster in Ukraine in 1986 heightened safety fears and effectively halted new reactor construction in the United States.

Now, CERA reports, 20 countries have new plants under construction. More than half will be built in five countries --- China, India, Japan, South Korea and the United States. Concrete could be poured at the earliest in the United States in 2010, the report said.

In the short term, a lack of manufacturing for reactor components and skilled personnel in the United States could constrict growth, CERA said.

The recent spike in the price of uranium, which has increased by about 700 percent since the 1990s, might also tighten the market.

But those are "growing pains" that can be overcome, the group said. Over the long haul, the industry must find places to store used fuel and prevent its materials from ending up in weapons, CERA wrote.

US will bank Tik Tok unless it sells off its US operations

  US Treasury Secretary Steven Mnuchin said during a CNBC interview that the Trump administration has decided that the Chinese internet app ...