| Vermont Yankee Nuclear Power Plant | |
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| Location | Vernon, VT |
| Coordinates | |
| Status | Operational |
| Commission date | November 30, 1972 |
| Licence expiration | March 21, 2032 |
| Operator(s) | Entergy |
| Architect(s) | Ebasco |
| Reactor information | |
| Reactor type(s) | BWR-4/Mark I containment |
| Reactor supplier(s) | General Electric |
| Power generation information | |
| Installed capacity | 620 MW |
| Annual generation | 4,703 GW·h |
| Website www.safecleanreliable.com |
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Vermont Yankee is a General Electric boiling water reactor (BWR) type nuclear power plant currently owned by Entergy. It is located in the town of Vernon, Vermont, and generates 620 megawatts (MWe) of electricity at full power. The plant began commercial operations in 1972. It provided 71.8% of all electricity generated in Vermont in 2008, which is 35% of the overall electricity used in the state.
In February 2010, the Vermont Senate voted 26 to 4 against re-licensing of the Vermont Yankee Nuclear Plant after 2012, citing radioactive tritium leaks, misstatements in testimony by plant officials, a cooling tower collapse in 2007, and other problems.[1] There is an absence of a clear plan to replace the electricity generated by the plant, which has caused concern among some businesses in Vermont.[2] Executives of Vermont's electric utilities have expressed confidence that they will be able to replace the electricity they now get from the plant.[3][4]
On March 21, 2011 the Nuclear Regulatory Commission issued their renewal of the operating license for the Vermont Yankee plant for an additional 20 years.;[5] the renewed license will expire March 21, 2032.
The nuclear plant's private owners filed a federal lawsuit on April 18, 2011, against a state law that gives the Vermont state legislature veto power over operation of the reactor when its current license expires next March.[6]
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Vermont Yankee is a BWR-4 Boiling water reactor with a Mark I containment structure. It provided 71.8% of all electricity generated in Vermont in 2008[7] and meets 35% of the overall electricity requirements of the state.[8]
It was originally designed and constructed for 500 MW electrical output. In 2006, it was upgraded to 620 MW electrical output. The reactor produces 1912 MW of heat which is converted to electricity at 32% efficiency to generate the 620 MW electrical output [9]
The reactor core holds up to 368 fuel assemblies, and 89 control rods.[10] The spent fuel pool is allowed to contain up to 3353 spent fuel assemblies.[10]
On July 31, 2002, Entergy Nuclear Vermont Yankee, LLC (EVY) purchased Vermont Yankee from Vermont Yankee Nuclear Power Corporation (VYNPC) for $180 million. Entergy received the reactor complex, nuclear fuel, inventories, and related real estate. The liability to decommission the plant, as well as related decommissioning trust funds of approximately $310 million, was also transferred to Entergy. The acquisition included a 10-year power purchase agreement (PPA) under which three of the former owners will buy a portion of the electricity produced by the reactor at a cost of approximately 4.5 cents per kilowatt hour.[11]
Vermont Yankee employs approximately 600 people including the employees that work out of the corporate location on Old Ferry Road in Brattleboro, VT.[12]
As a result of an NRC approved Extended Power Uprate (EPU), Vermont Yankee achieved its new rated power of 1,912 MWth (120% of its original licensed thermal power of 1,593 MWth) on May 6, 2006. The power increase was carried out in steps to allow collection of data on the reactor's steam dryer at various power levels, in accordance with the NRC imposed power ascension test plan.
In 1978, the Vermont Yankee reactor was the subject of Vermont Yankee Nuclear Power Corp. v. Natural Resources Defense Council, Inc., an important United States Supreme Court administrative law case which ruled that courts cannot impose procedures upon the NRC as this exceeds their power of judicial review.
The Nuclear Regulatory Commission defines two emergency planning zones around nuclear power plants: a plume exposure pathway zone with a radius of 10 miles (16 km), concerned primarily with exposure to, and inhalation of, airborne radioactive contamination, and an ingestion pathway zone of about 50 miles (80 km), concerned primarily with ingestion of food and liquid contaminated by radioactivity.[13]
The 2010 U.S. population within 10 miles (16 km) of Vermont Yankee was 35,284, an increase of 1.4 percent in a decade, according to an analysis of U.S. Census data for msnbc.com. The 2010 U.S. population within 50 miles (80 km) was 1,533,472, an increase of 2.9 percent since 2000. Cities within 50 miles include Brattleboro (6 miles to city center); Keene, N.H., (16 miles to city center); Fitchburg, Mass., (38 miles to city center).[14]
Vermont Yankee's spent fuel pool is nearing capacity. Since there is no projected date for operations start for the national long-term nuclear waste storage facility at the nuclear waste at Yucca Mountain Repository, Entergy Nuclear obtained approval for dry-cask storage[15] to avoid exceeding the pool's licensed capacity; this allows for continued operations to store additional spent fuel, beyond the original operating license term, ending in 2012. In lieu of relocation of spent fuel to an operating national nuclear waste repository, some of the spent fuel has been transferred to "dry-storage" casks on site; most of the spent fuel continues to be stored in the spent fuel pool.
Vermont Yankee began the first stage of its dry-cask storage program in May 2008. The first 97 short tons (88 t) fully loaded cask was accidentally dropped onto the refueling floor from a height of about 4 inches (100 mm), after being raised from the spent fuel pool. The accident was attributed to failure of a relay in the 110 short tons (100 t)-rated overhead crane. (The crane reportedly was tested in 1975 for only about 70% of the weight of a fully loaded cask.) In August 2008, Vermont Yankee successfully completed the first stage of its dry-storage program with the transfer of the fifth cask from the reactor building to a storage pad located above the 500 year floodplain of the Connecticut River. A large specially-designed cask-moving machine transports casks to the pad. Each cask contains 68 spent fuel assemblies.
Entergy Vermont Yankee applied to the Nuclear Regulatory Commission for a license extension of 20 years on January 27, 2006.[16] In early 2010, the Vermont State Senate voted 26–4 to block the Vermont Public Service Board (PSB) from considering continued operation of Vermont Yankee.[17]
On May 20, 2010, the NRC released a report on Vermont Yankee:
On March, 10, 2011 the NRC voted to conclude proceedings regarding renewal of the operating license for the Vermont Yankee Nuclear Power Station near Brattleboro, Vermont, for an additional 20 years.[19] The NRC issued the renewed license on March 21, 2011. The renewed license will expire March 21, 2032.[5]
On April 14, 2011 Entergy, the owner of Vermont Yankee sued the state of Vermont to stay open despite the Senate's blocking vote.[20]
For 2007, the use of this plant was estimated to prevent the release of 2.8 million short tons (2.5 Mt) of carbon dioxide CO2, 6.7 million tons (6.1 Mt) of sulfur dioxide (SO2), and 1.3 million tons (1.2 Mt) of nitrous oxides.[21]
Cooling for the plant's steam condenser is provided by circulating water through it, drawn from the adjacent Connecticut river. This water does not come in contact with the nuclear reactor and is not radioactive. The cooling towers are used to cool water returning from the condenser before it is discharged back into the river at times when it is too warm to comply with the environmental discharge permit. In 2007 the fourth cell of the west cooling tower collapsed, spilling some of the non-radioactive, cooling water. The collapse was an "industrial safety event," which did not threaten the integrity of the reactor or release any radiation into the environment. The NRC stated that the remaining cooling tower had enough capacity to allow the plant to operate at full output, however, until September 16, 2007 the reactor was kept at 50% power.
The cause of the collapse was found to be corrosion in steel bolts and rotting of lumber. Entergy has asserted that future inspections will be much more stringent in order to prevent further problems.
The cooling tower collapse caused Vermont's governor to question the reliability of the power station:[22] In March 2008, a State Senate committee recommended that the Legislature appoint a panel to oversee an independent review of the plant's reliability. The panel gave Vermont Yankee a generally positive review. "What this report suggests to me is there is not a cause or reason to seek the closure of the plant because of operational or safety concerns," said Public Service Commissioner, David O'Brien.[23]
In May 2009, the vice-president of operations at Vermont Yankee told the PSB during the reliability review that he did not believe there was any radioactively contaminated underground piping at the plant, but that he would check and respond to the panel.[24] In October 2009, Arnold Gundersen, a member of a special oversight panel convened by the Vermont General Assembly, confirmed that radioactive contamination had been detected in underground pipes. An Entergy spokesperson told Vermont Public Radio (VPR) that the earlier testimony was a "miscommunication."[24] On June 4, 2010, VPR reported that, because they had provided misleading information, Entergy Nuclear would be liable for legal expenses incurred by certain parties.[25]
In January 2010, it was reported that tritium, a radioactive isotope of hydrogen, had been discovered in a sample of ground water taken from a monitoring well the previous November.[26] The level of the isotope was initially below the acceptable limit for drinking water set by the Environmental Protection Agency.[27] By mid-January, however, the level had risen to 20,000 picocuries per liter (pCi/l), the federal limit for drinking water. The head of the Nuclear Regulatory Commission told Vermont’s congressional delegation that the agency would devote more resources to addressing concerns about Vermont Yankee, and that he expected the source of the tritium leak would be located within the next several weeks.[28]
On February 4, 2010, Vermont Yankee reported that ground water samples from a newly dug monitoring well at the reactor site were found to contain about 775,000 pCi of tritium per liter (more than 37 times the federal limit). On February 5, 2010, samples from an underground vault were found to contain 2.7 million pCi/l.[29] On February 14, 2010, the source of the leak was found to be a pair of steam pipes inside the Advanced Off-Gas (AOG) pipe tunnel. The pipes were repaired, stopping the leak.[26]
Samples taken from the river and other drinking water sources by the Vermont Department of Health showed no detectable levels of tritium.[30] The New Hampshire Department of Health and Human Services made a similar statement after several tests of the river.[31]
During the search for the source of the tritium leak, other radionuclides were found in the soil at the site. Levels of cesium-137 were found to be three to ten times higher than background levels. Silt in a pipe tunnel contained 2,600 picocuries/kg, but contamination outside the pipe tunnel was limited to a small volume, about 150 cubic feet (4.2 m3) of soil. According to the Vermont State Department of Health, there was no health risk from the cesium, as the quantities were small and it had not migrated.[30] (The level of cesium-137 was less than that present in many common foods. Bananas, for example, may contain 3,500 pCi/kg.[32])
Since cesium-137 is a fission product, it is an indicator of a nuclear fuel leak, but the consensus was that the cesium-137 probably leaked from defective fuel assemblies during or prior to 2001, when the last leak of that type was reported by Vermont Yankee. (Problems with fuel rods were common in the 1970s and 1980s.)[33]
In early November, 2010, a water leak[34] caused by a faulty weld caused a "conservative" four-day shutdown while the pipe involved was repaired. A company spokesman said that "if plant managers had known on Sunday night what they knew on Monday, they might have tried to fix the leak while the plant kept running."[35]
During the week of January 17, 2011, tritium was detected at a level of 9,200 picocuries per liter (below the federally-required reporting level) in an area 150–200 feet north of the location where it was detected a year earlier. According to the State's radiological health chief at the Vermont Health Department, Bill Irwin, and Vermont Yankee spokesman, Larry Smith, the source of the leak is not yet known. Irwin and Governor Peter Shumlin expressed concern about the discovery.[36]
The Nuclear Regulatory Commission performed a tri-annual inspection July–August 2008. It found three "minor faults." An Associated Press report said that it had won "high marks."[37]
The Nuclear Regulatory Commission's estimate of the risk each year of an earthquake intense enough to cause core damage to the reactor at Vermont Yankee was 1 in 123,457, according to an NRC study published in August 2010.[38][39]
Polls have found that a majority of Vermonters oppose relicensure of Vermont Yankee.[40][41]
In February 2010, the Vermont Senate voted 26 to 4 against allowing the PSB to consider re-certifying the Vermont Yankee Nuclear Plant after 2012, citing radioactive tritium leaks, misstatements in testimony by plant officials, a cooling tower collapse in 2007, and other problems.[1] Some businesses in Vermont are concerned there is an absence of a clear plan to replace the electricity generated by the plant. A spokesman for IBM, the largest private employer in the state, and the state's largest consumer of electricity, said "we have to be smarter than this".[2] Larry Reilly, president of Central Vermont Public Service Corp., Vermont's largest utility, stated in 2011 that he was untroubled by the prospect of closure. "There's plenty of power out there . . . The bottom line is that it's not a big problem for us. Historically we have used 140 megawatts [from VT Yankee] and we have been planning for years to close this gap through diversification."[4] Reilly also stated that he did not expect the price of electricity in Vermont to increase if Vermont Yankee closed.[4] Analysis by researchers at the University of Vermont estimated that an increase of "slightly more than 3 percent" in the retail price of electricity in Vermont would result from closing Vermont Yankee.[9]
Governor Peter Shumlin is a prominent opponent of the Vermont Yankee. Two days after Shumlin was elected governor in November 2010, Entergy put the plant up for sale.[42]
There have been many protests against continued operation of the plant.[43][44][45] On March 22, 2011, the day after the NRC issued Vermont Yankee's license extension, Vermont's congressional delegation—Senator Patrick Leahy (D), Senator Bernie Sanders (I), and Representative Peter Welch (D)—issued a joint statement decrying the NRC's action and noting the similarity of Vermont Yankee to units then in partial meltdown at the Fukushima Daiichi power station, Japan.[46]
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