ICEM11 Final Program 9.7.11pm_ICEM07 Final Program ... - Events

Abstracts Session 25
3) THE COMPLEX CHALLENGE OF REFURBISHING THE POND GANTRY STEELWORK
WHICH SUPPORTS THE POND SKIP HANDLER ABOVE THE FIRST GENERATION
MAGNOX STORAGE POND AT SELLAFIELD (wP-59133)
Ian Richardson, Sellafield (UK)
The First Generation Magnox Fuel Storage Pond (FGMSP) provided fuel storage and decanning capability from the early
1960s until 1986.
A significant programme of work has been underway since the completion of operational activities to support the programmes
strategic intent of retrieving and storing all legacy wastes, and remediating the structure of the plant to support decommissioning
activities.
A key enabler to the retrievals programme is the Pond Skip Handler Machine (SHM), removed from service in 2002 following
the discovery of significant signs of corrosion, an inevitable consequence of being located in a coastal, salt laden environment.
The SHM provides sole capability to access and retrieve the inventory of the fuel skips in the pond. It is also fundamental to
future operations and the deployment of desludging equipment to recover bulk sludges from the pond floor.
This paper will examine the challenges faced by the team as they successfully defined, planned and executed remedial work
to a specific aspect of the civil structure, the SHM gantry rail system, using a purpose built refurbishment platform; the Gantry
Refurbishment System.
The paper will examine how an innovative approach was adopted to resolve the related issues of:
• Refurbishing an aged structure to….
4) SYSTEMATIC CHEMICAL DECONTAMINATION USING IF7 GAS (wP-59036)
Haruhi Hata, Kaoru Yokoyama, Noritake Sugitsue, Japan Atomic Energy Agency (Japan)
Since 1979, Uranium enrichment technology has been researched through the gas centrifuge method, at Ningyo-toge Environmental
Engineering Center of Japan Atomic Energy Agency(JAEA). In addition, the Demonstration Plant, that is final stage test
facilities, was operating continuously from 1988 to 2001.
As a result, a lot of residues accumulated in the plant. Most of this accumulation was found be uranium intermediate fluoride.
The basic decommission policy of JAEA is that equipments of gas centrifuge will be decontaminated by sulfuric acid immersion
method for clearance and reuse.
In our plan, approximately 90% of metals will be cleared and reused, and then the remaining 10% will be disposed of radioactive
waste.
We propose a combination of sulfuric acid immersion method and the systematic chemical decontamination as an efficient
method for decontamination of uranium enrichment facilities. This paper focuses on the method and performance of systematic
chemical decontamination using IF7gas. The following (Figure 1)shows our decommission policy and position of systematic chemical
decontamination by IF7gas for uranium enrichment plant...
5) DECOMMISSIONING & DEMOLITION OF FACILITIES USED FOR THE STORAGE
& STABILISATION OF WATER REACTOR SLUDGE (wP-59097)
Nicholas J. Brown, Rowland Cornell, Nuvia Limited; Andy Staples, RSRL (UK)
Nuvia Limited was contracted to design, build and operate a waste treatment plant to stabilise a quantity of about 300m3 of
active sludge stored in the External Active Storage Tanks (EAST) at the former United Kingdom Atomic Energy Authority
(UKAEA) research site at Winfrith, UK. At the end of this process both the old and new plants are to be decommissioned and
demolished with the minimisation of waste material volumes. The sludge was produced in the Steam Generating Heavy Water
Reactor (SGHWR) during 30 years of operation, which is now in the early stages of decommissioning. As part of the reorganisation
of UKAEA responsibility for the site now lies with RSRL (Research Sites Restoration Limited) with funding provided by the
Nuclear Decommissioning Authority (NDA).
The process of stabilisation of the SGHWR sludge from the EAST tanks within 500 litre stainless steel drums in the newly
constructed Winfrith EAST Treatment Plant (WETP) was completed in March 2010. Now that these operations have been completed,
the plant has entered a full decommissioning phase since no further work on any other waste materials have been identified by
the client.
This paper describes the development of a decommissioning plan for the mixture of old…
6) DECOMMISSIONING OF THE RADIO CHEMICAL HOT LABORATORY OF THE
EUROPEAN COMMISSION JOINT RESEARCH CENTRE OF ISPRA (wP-59207)
Daniele Ugolini, Francesco Rossi, Francesco Basile, European Commission Joint Research Centre (Italy)
The construction of the Radio Chemical Hot Laboratory (RCHL) of the Joint Research Centre (JRC) of Ispra began in the early
1960s while the laboratory activities started in 1964. In 1976 an annex to the main building was built. At this time the RCHL main
research activities were in environment and biochemistry by means of radioactive tracers; neutron activation analyses; extraction
of actinides from radioactive liquid waste coming from the nuclear fuel reprocessing plants; and analyses of U, Pu, and Th in samples
from the nuclear fuel cycle in order to determine the isotopic ratio and the burn-up. In 1978, a new area of laboratories named
Stabularium was built to study the metabolism of heavy metal on laboratory animals. Complementary to the laboratory three pneumatic
transfer systems for irradiated sources connected the RCHL to two research reactors.
The decommissioning activities of the 2650 m2 facility started in January 2008 and they were completed at the end of 2010
with the release for unrestricted use of all the buildings of the facility. They consisted in five main tasks: pre-decommissioning,
licensing, dismantling, waste management, and final survey. The main pre-decommissioning activities were the physical and radiological
characterization of the facility. The principal…
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