The Watts Bar Nuclear Plant near Spring City, Tenn., has become the first nuclear power plant in America to gain regulatory approval for meeting new equipment and safety standards adopted in the wake of the 2011 earthquake and tsunami at the Fukushima nuclear plant in Japan.
The U.S. Nuclear Regulatory Commission said the Tennessee Valley Authority has upgraded plant safety systems, emergency pumping equipment and preventative maintenance programs to sufficiently protect Watts Bar against any natural or man-made disasters similar to what crippled the safety systems at three of the five reactors at the Fukushima plant.
The approval is one of the last major steps for TVA to gain a nuclear license to operate a second reactor at the Watts Bar plant near Spring City — the first new nuclear unit to be added to America's grid in nearly two decades.
"Every nuclear facility, at some point, is going to have to do what it can to ensure the safety of its workers and the public in the event of something like Fukushima happening," TVA spokesman Scott Brooks said Tuesday. "We have been working on mitigation strategies at Watts Bar even before the NRC came out with its requirements and as a result we are the first nuclear power station in the country to be inspected by the NRC and we have passed."
NRC inspectors in April reviewed TVA's $80 million Flex building — a concrete bunker used to store backup equipment and generators — along with TVA's elevated diesel generator units and other new safety systems and processe. The additional equipment and procedures were implemented at Watts Bar to comply with changes based upon the NRC's post-Fukushima safety analysis.
TVA is spending $180 million to upgrade safety systems at its operating plants at Watts Bar, Sequoyah and Browns Ferry in response to NRC-ordered improvements to limit chances of a Fukushima-type accident in the United States.
The NRC is still considering other changes U.S. nuclear plants may have to make in response to Fukushima. But Anthony Masters, chief of the reactor projects unit for the NRC, said regulators determined Watts Bar has met all of the changes required so far.
In Japan, radiation leaked from Fukushima into the atmosphere and the Pacific Ocean four years ago when an earthquake and subsequent tsunami destroyed reactor buildings and backup power systems, forcing authorities to evacuate 160,000 residents from the area. About half of those resident will not be allowed to return to their homes even by 2017.
Fukushima exposed the vulnerability of nuclear power plants when multiple disasters strike at the same time. Tokyo Power Co. President Naomi Hirose conceded that the utility's "safety culture, skills and ability were all insufficient" and contributed to the nuclear meltdown, which officials had previously thought could not happen.
To avoid a similar calamity at Watts Bar should TVA dams break or if the plant was hit with a tornado or missile attack, TVA elevated flood-vulnerable equipment and backup systems and erected a concrete bunker building to store backup power and restoration equipment.
In a letter to TVA this week, Masters said NRC inspectors "did not identify any findings or violations of more than minor significance."
TVA rushed ahead of most utilities to comply with the new post-Fukushima rules in order to stay on pace to finish its final $4.2 billion construction phase for the Unit 2 reactor at Watts Bar. The plant was started in 1973 and has been started and stopped several times since.
TVA is currently testing the equipment at Watts Bar Unit 2, under the eye of NRC inspectors, to ensure that equipment installed over the past four decades performs adequately under the 586-degree temperature (Fahrenheit) and 2,235-pounds-per-square-inch pressure that pipes and safety systems will operate under when the nuclear plant is running.
If the "hot functional tests" begun last month prove adequate, the NRC is expected to issue a license for the Unit 2 reactor by late summer or early fall. Then TVA will load the nuclear fuel into the reactor core and begin power ascension testing later this year, Brooks said.
The Unit 2 construction project continues to employ about 2,100 workers — down from 3,300 workers earlier this year — as TVA tests equipment for a planned unit startup by the end of 2015.
The 1,150-megawatt unit is capable of supplying the electrical power needs of about two cities the size of Chattanooga.
Contact Dave Flessner at firstname.lastname@example.org or at 757-6340.