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    A former Three Mile Island Unit 2 plant program supervisor who was on-site when that reactor partially melted down in 1979 is confident that TMI Unit 1 can run safely for another 20 years.

    And that's good news since the U.S. Nuclear Regulatory Commission could approve TMI Unit 1's application to extend it operating license to 2034 as early as November.

    "I think it's a high probability that the NRC will allow TMI 1 to operate for another 20 years," said Dick Dubiel, co-owner of Woodstock, Ga.-based Millennium Services Inc., a consulting firm that specializes in the decommissioning of
    nuclear facilities such as outdated uranium enrichment plants.

    At the time of the TMI Unit 2 partial meltdown on March 28, 1979, Dubiel supervised the plant's radiation, protection and chemistry program.

    On Jan. 8, 2008, the owners of TMI Unit 1 filed an application with the commission requesting that its operating license be extended from 2014 to 2034, said Neil Sheehan, an NRC spokesman.

    As part of its application review, the NRC has focused on two areas: the plant's aging management program and what effects the power station would have on the surrounding environment should it operate for another two decades, he said.

    In terms of the environmental impact, the NRC rated the plant's radiological releases and other adverse impacts from the plant as minimal.

    Essentially, no environmental impacts exist that would preclude a 20-year extension of TMI Unit 1's operating license, Sheehan said.

    The NRC, at least preliminarily, approved the plant's aging management program.

    Basically, NRC officials inspected the plant to ensure that it had a robust program in place to manage the effects of aging on key safety systems, structures and components at the plant.

    A component at the plant would be a steam generator that functions to power a turbine, which in turn, produces electricity.

    This fall, Exelon Nuclear, the owner and operator of TMI Unit 1, will invest more than $300 million in major upgrades at the plant.

    The lion's share of those funds will pay for the replacement of two steam generators, each weighing more than 500 tons, said Ralph DeSantis, a plant spokesman.

    Also, the plant will upgrade its control-rod drive system to digital allowing operators to more efficiently position the neutron-absorbing rods, he said.

    Now, the plant's control-rod drive system is analog and features an illuminated grid sprawled across panels in the main reactor's control room that provides an indication if a rod has been installed into the core or not, Sheehan said.

    With digital switchover, control room operators will have access to flat-panel displays that will show where the control rods are at any given time.

    When the plant restarts its reactor after a refueling outage, operators remove the control rods so that that the reactor will once again produce heat eventually leading the turbines to produce electricity.

    While TMI's license renewal application still needs to be reviewed by experts independent of the NRC, the fact that the commission has given positive marks to key aspects of the review bodes well for the plant, Sheehan said.

    And Dubiel said he believes that TMI's design could have the plant possibly operating past 2034.

    Despite TMI Unit 2's partial meltdown, Dubiel said that TMI Unit 1 and other nuclear-power reactors built in the 1960s through 1980s have not worn nearly as much as engineers had previously predicted for a 40-year power station.

    Next to hydro-electric power, nuclear energy is the most widely used inexpensive form of power, he said.

    "The energy is cheap, clean and reduces our dependence on oil," Dubiel said. "The cheaper the power, the stronger the economy."

    sadkins@ydr.com; 771-2047

    Three Mile Island emergency indelibly written into memories: Read more at York Town Square blog.