Millstone Nuclear Power Plant

Millstone Nuclear Power Plant
location
Coordinates	41 ° 18 ′ 37 ″  N , 72 ° 10 ′ 6 ″  W Coordinates: 41 ° 18 ′ 37 ″  N , 72 ° 10 ′ 6 ″  W
Data
Owner:	Dominion Resources, Inc.
Operator:	Dominion Energy
Active reactors (gross):	2 (2,198 MW)
Decommissioned reactors (gross):	1 (684 MW)
The data source of the respective entries can be found in the documentation .

Millstone is the only nuclear power plant in the US state of Connecticut . It is located on a former quarry, after which it is named, on the Niantic Bay of the Atlantic Ocean in the urban area of Waterford . It consists of three reactors, a decommissioned boiling water reactor and two active pressurized water reactor units . The two active units have an operating capacity of 2198 MW. In terms of production capacity, Millstone is the largest electrical utility in New England , and Unit 3 is the largest in New England.

history

The power plant area has a size of 2 km². The complex was built by a consortium of utility companies on Niantic Bay, which is on Long Island Sound . The latter supplies the cooling water for the power plant.

Although located in Waterford, Millstone is best seen from Niantic. It is visible from the Niantic boardwalk and the Niantic River Bridge, as well as to Amtrak rail travelers on the NEC line, which passes Niantic Bay.

Block 1 is a boiling water reactor. Units 2 and 3, both pressurized water reactors (one from Westinghouse and one from Combustion Engineering ), were sold by Northeast Utilities to Dominion Resources in 2000 .

The nuclear power plant uses almost 50,000 hectoliters per minute for cooling. During the spawning season, the reactor output is reduced in order to protect the local fish stocks. The original operating license for the operation of Unit 2 expired in 2015. The Connecticut government has examined whether Millstone should be upgraded with an active cooling system in the form of cooling towers. Had this been the case, three cooling towers would have had to be built - one for Block 2 and two for Block 3. The cost would have been one billion US dollars, according to Dominion spokesman Ken Holt. Similar circumstances have already led to a ten-year reduction in service life at the Oyster Creek nuclear power plant . The active units of the Millstone Nuclear Power Plant were therefore among the 12 nuclear power plants in the United States most at risk of decommissioning in the coming years, according to a report by Mark Cooper. In July 2014, the NRC increased the permitted maximum temperature of the cooling water from 75 to 80 degrees, making retrofitting obsolete.

In December 2016 it became known that Millstone was also affected by the Creusot Forge scandal over falsified certificates. Parts of the pressurizer in block 2 come from the burdened Areva subsidiary.

Reactor blocks and data

Block 1

Millstone 1 was a General Electric - boiling water reactor with an operating capacity of 660 MW . It was shut down in November 1995 and finally shut down in July 1998.

• May 19, 1966: Building permit granted
• 0November 1, 1968: Safety report published
• 0October 7, 1970: Operating license issued
• October 26, 1970: First criticality
• November 27, 1970: Network synchronization
• December 28, 1970: Commercial operation
• 0January 6, 1971: First operation under full load
• December 21, 1995: The US nuclear regulatory agency NRC opens a safety investigation. The reason for this are cost-saving procedures for equipping the reactor with fuel elements , which contradict the regulations. The information was leaked to the agency by George Galatis, a nuclear engineer.
• February 20, 1996: Leaking safety valve leads to shutdown. The subsequent inspection reveals numerous deficiencies.
• July 21, 1998: Final shutdown for economic reasons

Block 2

Millstone 2 is a combustion engineering pressurized water reactor that was built in the 1970s. Its operating capacity is 870 MW. It is equipped with two steam pressure generators and four reactor cooling pumps. When the fuel was filled in October 2006, the operator installed a new printer holder.

• December 11, 1970: Building permit granted
• August 15, 1972: Safety report published
• September 26, 1975: Operating license issued
• October 17, 1975: First criticality
• December 26, 1975: Commercial operation
• March 20, 1976: First operation under full load
• June 25, 1979: Increase in performance
• November 28, 2005: 20-year extension granted
• July 31, 2015: Operating license expires
• July 31, 2035: The extended operating license expires

Block 3

Millstone 3 is a Westinghouse pressurized water reactor that was first started up in 1986 and has an operating capacity of 1150 MW.

• August 9, 1974: Building permit granted
• January 23, 1986: First criticality
• April 23, 1986: Commercial operation
• November 28, 2005: 20-year extension granted
• November 25, 2025: The operating license expires
• November 25, 2045: The extended operating license expires

Incidents

On February 26, 1996, a leaky safety valve led to the shutdown of units 1 and 2. During the subsequent test, numerous defects were discovered.

In September 2009, Unit 2 was shut down after a thunderstorm caused power fluctuations. When workers tried to restart the block, they discovered a leak in the reactor cooling pump.

• December 21, 2009 Millstone 3: Incident, reactor shutdown for more than 72 hours.
• July 27, 2009 Millstone 2: Incident, reactor shutdown for more than 72 hours.

On August 9, 2013, there was an incident in reactor block 3 due to a malfunction and a subsequent emergency reactor shutdown.

On May 25, 2014 there was an emergency reactor shutdown of the two active units, after which "slightly" radioactive water that had leaked was discovered.

On October 4, 2015, there was an incident in which a "small" leak occurred, from which around 25 gallons (90 liters) of cooling water escaped per minute. The incident was classified as an "unusual event".

Operating license

In the USA, the Nuclear Regulatory Commission (NRC) grants an operating license for a nuclear power plant for a period of up to 40 years. The 40 year period was originally based on the fixed asset depreciation period . The Atomic Energy Act of 1954 allows the operating license to be extended (even several times) by 20 years at a time.

The original operating license for Unit 2 was granted to the operator Dominion Nuclear Connecticut, Inc. on September 26, 1975 by the NRC. It was extended on November 28, 2005 to July 31, 2035. The original permit for Block 3 was granted on January 31, 1986. It was extended on November 28, 2005 to November 25, 2045.

Data of the reactor blocks

Reactor block	Reactor type	net power	gross power	start of building	Network synchronization	Commercialization of essential operation	operating permit	Shutdown
Millstone-1	Boiling water reactor	641 MW	684 MW	05/01/1966	11/29/1970	03/01/1971		06/01/1998
Millstone-2	Pressurized water reactor	869 MW	918 MW	11/01/1969	11/9/1975	December 26, 1975	07/31/2035
Millstone-3	Pressurized water reactor	1,229 MW	1,280 MW	08/09/1974	02/12/1986	04/23/1986	11/25/2045

See also

• List of nuclear power plants
• List of the most powerful nuclear reactors

Web links

Commons : Millstone Nuclear Power Plant  - Collection of pictures, videos and audio files

Individual evidence

1. ↑ https://www.hartfordbusiness.com/article/millstone-nuclear-approved-for-warmer-cooling-water
2. ↑ https://nrcpublicblog.files.wordpress.com/2017/01/ml17009a275.pdf
3. ↑ http://wpri.com/2015/10/04/ct-nuclear-plant-suffers-minor-coolant-leak
4. ^ Backgrounder on Reactor License Renewal. Nuclear Regulatory Commission (NRC), accessed November 18, 2017 . 
5. ^ Subsequent License Renewal Background. NRC, accessed November 18, 2017 . 
6. ↑ Millstone Power Station, Unit 2. NRC, accessed November 20, 2017 . 
7. ↑ Millstone Power Station, Unit 3. NRC, accessed November 20, 2017 . 
8. ↑ MILLSTONE-1. IAEA - Power Reactor Information System (PRIS), accessed on November 20, 2017 . 
9. ↑ MILLSTONE-2. IAEA - PRIS, accessed November 20, 2017 . 
10. ↑ MILLSTONE-3. IAEA - PRIS, accessed November 20, 2017 .