Florida decommissioning cost drop signals nuclear industry progress
As Duke Energy nears the end of major license termination activity at its Crystal River 3 plant in Florida, a site-specific study shows decommissioning costs are 10% lower than 2013 estimates.
Duke Energy submitted its latest decommissioning cost estimate for the 860 MW Crystal River 3 plant to the NRC in June, predicting total costs at $895.9 million (in 2017 dollars).
The new cost estimates followed an updated decommissioning cost report by sector specialists TLG Services, delivered to Duke in May.
Back in 2013, Duke Energy estimated total decommissioning costs at $1.18 billion including around $286 million expected in 2013-2017.
The reduced cost estimate since 2013 is mostly due to actual costs incurred, but costs have also been “about 10% lower than anticipated,” Duke Energy said.
Duke has opted for deferred decommissioning of Crystal River 3 under the SAFSTOR procedure, rather than “immediate” decommissioning under DECON.
The new cost estimate includes $749 million for license termination activities, including the placement of the unit in safe storage, ongoing caretaking during dormancy and the eventual physical decontamination and dismantling. The cost of spent fuel management, interim storage and eventual transfer is estimated at $95 million and the cost of the demolition of the designated structures and site restoration work is estimated at $52 million.
All costs are expected to be met by a Nuclear Decommissioning Trust Fund (DTF) which totalled $743 million at the end of 2017 and is expected to grow over the coming decades.
U.S. total NDT fund balances have risen significantly since a dip during the 2008 financial crisis.
US decommissioning fund balances
(Click image to enlarge)
Source: Callan consultancy (2017).
The change in the Crystal River cost outlook highlights the challenge of estimating total costs for the long-term SAFSTOR decommissioning procedure amid continuous advancements in technology and planning.
Low wholesale prices have accelerated nuclear closures and many U.S. operators are instead choosing to perform immediate decommissioning. Growing demand for dismantling and decontamination (D&D) services has spurred companies to create new decommissioning joint ventures and business models.
Crystal River 3 was permanently closed in 2013 following escalating repair costs and the plant reached SAFSTOR condition in July 2015. Duke began construction of a dry cask Independent spent fuel storage installation (ISFSI) at the site in 2016, and fuel transfer to the ISFSI was completed in January 2018 after a 41-month process.
In February 2018, the NRC approved the security plan for the plant's amended status as a dry cask storage facility, submitted in May 2016. This approval will allow the decommissioning team to reduce costs "to help ensure continued sufficiency of the Nuclear Decommissioning Trust Fund," Duke said.
In TLG's latest cost estimate, the most important components of overall costs are program management (34%), removal of material (13.9%), security (11.1%) and non-labor reoccurring (10.3%).
Contingency costs are incorporated into each sub-budget to cover unforeseeable factors, such as labor stoppages, weather delays, tool breakage, accidents and illnesses, it said.
To form the estimate, TLG used new information and learnings from ongoing completed decommissioning programs, including its estimations for the Shippingport and Cintichem projects, completed in 1989 in 1997, it said.
“Modifications [to the 2013 methodology] were incorporated where new information was available or experience from ongoing decommissioning programs provided viable alternatives or improved processes,” TLG said.
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Key areas in which the nuclear industry has improved decommissioning efficiency include regulatory planning, the speed of spent fuel removal, component segmentation and the optimization of dismantling and spent fuel activities. This can have a significant impact on labor costs.
Crystal River plant workers are continuing to disconnect equipment no longer needed and remove non-fuel radiological components and this is expected to be completed by mid-2019.
Duke estimates license termination costs in 2018 at $99.8 million and costs associated with spent fuel at $17.7 million, according to its latest "Crystal River Unit 3 Nuclear. Generating Plant Post-Shutdown Decommissioning Activities Report”. As the below chart shows, annual spending is predicted to drop sharply in 2019.
Crystal River 3 spending plan: 10-year outlook
Source: Nuclear Energy Insider. Data source: Duke Energy's Annual Decommissioning and Irradiated Fuel Management Financial Status Report for 2017 (March 2018).
Long term risks
In Europe and the U.S., operators have been urged to commence decommissioning activities as early as possible in order to avoid escalating cost risks over time.
The deferral of D&D activities exposes operators to long-term risks such as rising regulatory requirements, additional leakage risks and loss of crucial expertise as workers leave the industry, Geoffrey Rothwell, Principal Economist at the OECD’s Nuclear Energy Agency, told Nuclear Energy Insider in 2016.
Under the current plan, Duke expects to be able to transfer the spent fuel from Crystal River 3 to a permanent storage facility by 2037. In its cost report, TLG assumed that most low-level radioactive material will be transferred to EnergySolutions’ Clive Disposal Facility in Utah, while Class B and C waste would be transferred to Waste Control Specialists’ facility in Texas.
Site restoration must take place by 2074, although Duke may choose to modify this timeline.
By Neil Ford