SIZE REDUCING ZION UNIT-2 FOR WASTE DISPOSAL

In a first-of-its-kind initiative, the U.S. Nuclear Regulatory Commission (NRC) approved a license transfer of ownership to begin the immediate decommissioning of the Zion Nuclear Power Station in Illinois. On September 1, 2010, EnergySolutions officially became owner and operating licensee of the plant which had been constructed, operated and shut down by Exelon Nuclear.

In a first-of-its-kind initiative, the U.S. Nuclear Regulatory Commission (NRC) approved a license transfer of ownership to begin the immediate decommissioning of the Zion Nuclear Power Station in Illinois. On September 1, 2010, EnergySolutions officially became owner and operating licensee of the plant which had been constructed, operated and shut down by Exelon Nuclear.

Working closely with Exelon Nuclear to prepare for this decommissioning and land restoration project, EnergySolutions formed ZionSolutions, a special-purpose license stewardship company created to deliver integrated services and solutions for the safe cleanup and environmental restoration of the Zion Station site. Once the cleanup is complete, the license and land will be transferred back to Exelon.

The benefits of this transaction include cleanup and land restoration, accelerated by at least 12 years, and completing the nuclear plant life cycle by safely decommissioning America’s largest shut-down commercial nuclear power plant. No additional funds from Illinois electric rate-payers will be contributed for the project, and there will be considerable economic benefits for the local community in terms of jobs, goods and services. The Zion Nuclear power plant campus consists of 257 acres located on the shores of Lake Michigan. The plant was constructed from 1968 to1973. The twin 1040-megwatt reactors operated for more than 24 years, employing more than 1,200 site workers and contractors. After shutdown, the plant remained in long-term safe storage until EnergySolutions became the Zion plant’s licensee. Work began immediately after the license transfer.

Three of the major steps to decommission a nuclear power plant include:

• The preparation and transfer of spent fuel from wet to dry storage;

• The equipment removal and major structure demolition; and

• The License Termination phase, including the final site characterization and verification that the land meets NRC release criteria for beneficial future use of the land.

The spent fuel is currently stored in the spent fuel pool located below ground between the containment buildings. Transferring the spent fuel to dry storage containers allows decommissioning and site restoration to be completed sooner because the spent fuel pool building can be dismantled along with the other structures.

ZionSolutions will load the fuel underwater into stainless steel storage canisters, which will then be dewatered and sealed. These canisters will then be inserted into concrete casks and placed on a seismically designed three-foot concrete pad. The combined casks and canisters are designed to withstand tornados, tornado-driven debris, flooding, accidental fire, earthquakes and tip over accidents. Fully loaded with spent fuel, the canisters weigh 314,000 pounds each. The dry casks are heavily shielded and meet stringent design and licensing requirements of the NRC.

Once the dismantlement of the plant is in full swing, the vast majority of radiologically contaminated plant equipment, piping and building demolition debris will be shipped by rail from the Zion Station to EnergySolutions’ disposal facility, known as Clive, located in Utah’s west desert. The materials shipped to Clive are classified as “Class A” LLRW (low-level radioactive waste), and are the lowest category of nuclear waste. The expert team of operators, technicians and safety personnel will ensure that waste is disposed of properly, safely and in full compliance with the requirements of the State of Utah and NRC.

The Clive disposal facility is located 70 miles west of Salt Lake City, Utah, and is the United States’ largest and most comprehensively licensed commercial LLRW disposal facility. The site’s remote location, low annual rainfall and stable geology are some of the reasons why Clive is favorable for this type of material. Larger components, such as turbines, reactor vessels and steam generators from the Zion Station, will be packaged and shipped intact for disposal at Clive.

ZionSolutions will work closely with the Department of Transportation, the NRC, the State of Illinois and the Transportation Security Administration, including post- 9/11 security plans to ensure that all shipments are compliant and approved for shipping. Radioactive materials will also be tracked ensuring a safe arrival to the Clive disposal facility.

With the exception of the spent fuel storage pad, ZionSolutions plans to completely dismantle the plant and restore the site by 2020. This will involve demolition and removal of clean equipment, buildings and structures from the site that remain after decommissioning of the contaminated structures is completed. These structures include the Service Building, Turbine Building, Crib House and various other warehouses and office buildings.

Where work involves site excavations, ZionSolutions will backfill and stabilize below-grade openings and cavities, then grade and seed the site to achieve a natural contour with the surrounding environment. At the conclusion of site restoration, the electrical switchyard and spent fuel storage pad will remain, while the rest of the property will be ready for beneficial use before transferring back to Exelon.

Once the site is restored, the NRC license will be amended to reflect completion of radiological decommissioning work and to cover future spent fuel monitoring until the DOE removes the spent fuel. This project will be completed 12 years sooner than the originally projected completion date of 2032.

ZionSolutions is dedicated to the safety of the employees, citizens and communities surrounding Zion and the environment. To fully comply with NRC criteria, physical barriers and state-of-the-art electronic security and surveillance technology will be employed. Security officers are stationed at the installation 24 hours a day, 7 days a week, consistent with current nuclear security practices. This project will serve as a precedent for decommissioning other large-scale nuclear power plants in America and around the world.

About the Author:
Val J. Christensen serves as the chief executive officer and president of EnergySolutions, Inc., a nuclear-energy services and environmental restoration company with operations in the United States and around the world.