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May 31–June 3, 2026
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Latest News
Browns Ferry’s reactors receive subsequent license renewals
The operating licenses for the three boiling water reactors at Browns Ferry nuclear power plant, in Athens, Ala., have each been renewed by the Nuclear Regulatory Commission for an additional 20 years. The reactors, operated by the Tennessee Valley Authority, are now licensed to operate until December 2053 for Unit 1, June 2054 for Unit 2, and July 2056 for Unit 3.
Kenneth Hoar, Piotr Nowinski, Vernon Hodge, James Cizdziel
Nuclear Technology | Volume 175 | Number 1 | July 2011 | Pages 351-359
Technical Paper | Special Issue on the 16th Biennial Topical Meeting of the Radiation Protection and Shielding Division / Environmental Effects of Nuclear Technology | doi.org/10.13182/NT11-A12307
Articles are hosted by Taylor and Francis Online.
Rock varnish samples were collected near three point sources of air pollution to determine if the varnish contained a record of recent air pollution. Samples were collected as follows: downwind of the Nevada Test Site (NTS); in the fallout pattern of the shuttered Mohave Power Plant, located in Laughlin, Nevada; and, near the operating Reid-Gardner Power Plant, just east of Las Vegas, Nevada. Analysis of the NTS rock varnish shows 240Pu/239Pu mass ratios as low as 0.0592 ± 0.0003 and 241Pu/239Pu ratios as low as 0.00063 ± 0.00004, compared to worldwide values of 0.18 ± 0.01 and 0.009 ± 0.002, respectively, clearly indicating that the varnish can be used as a forensic tool for identifying the source of air pollution, in this case the NTS. The samples collected in the plumes of the coal-fired power plants contain thorium and uranium, and have 232Th/238U mass ratios from 1 to 30, and concentrations from 5 to 755 ppm for Th and 1 to 578 ppm for U. The highest concentrations of these elements occur together at locations that implicate the power plants; however, additional samples would be required to demonstrate unequivocally that the power plants are the sources. Overall, it is apparent that rock varnish can be utilized as a passive monitor to investigate recent air pollution.
