The 12th International Conference on Environmental ... - Events

Session 46-48 Abstracts
affected village, Pellérd suffered about 1 mSv extra annual dose due to the emission of tailings ponds. Decrease of occupational
dose was also indicated on the tailings pond workplaces: the earlier measured 56 mSv/year (without cover) decreased to the satisfactory
11.5 mSv/year value as covering of the highly radioactive surface progressed. <strong>The</strong> decisive component of excess dose is the
short living radioactivity (radon daughters) in air.
SESSION 46 - PANEL: UK NDA AND TIER 1 FUNDING, CONTRACTING,
SUBCONTRACTING SELECTION AND ARRANGEMENTS
ABSTRACTS NOT REQUIRED
SESSION 47 - PANEL: UMREG PANEL/ROUNDTABLE
ABSTRACTS NOT REQUIRED
SESSION 48 - LIQUID WASTE TREATMENT PROCESS AND EXPERIENCE
1) U.S. DEPARTMENT OF ENERGY’S - 16037
Dennis Kelley, Pacific Nuclear Solutions (USA); Yury Pokhitonov, V.G. Khlopin Radium Institute(Russia)
Large amounts of liquid radioactive waste have existed in the U.S. and Russia since the 1950’s as a result of the Cold War.
Comprehensive action to treat and dispose of waste products has been lacking due to insufficient funding, ineffective technologies
or no proven technologies, low priority by governments among others. Today the U.S. and Russian governments seek new, more
reliable methods to treat liquid waste, in particular the legacy waste streams. A primary objective of waste generators and regulators
is to find economical and proven technologies that can provide long-term stability for repository storage.
In 2001, the V.G. Khlopin Radium Institute (Khlopin), St. Petersburg, Russia, and Pacific Nuclear Solutions (PNS), Indianapolis,
Indiana, began extensive research and test programs to determine the validity of polymer technology for the absorption and
immobilization of standard and complex waste streams. Over 60 liquid compositions have been tested including extensive irradiation
tests to verify polymer stability and possible degradation. With conclusive scientific evidence of the polymers effectiveness in
treating liquid waste, both parties have decided to enter the Russian market and offer the solidification technology to nuclear sites
for waste treatment and disposal.
In conjunction with these efforts, the U.S. Department of Energy (DOE) will join Khlopin and PNS to explore opportunities
for direct application of the polymers at predetermined sites and to conduct research for new product development. Under DOEs
Initiatives for Proliferation Prevention(IPP) program, funding will be provided to the Russian participants over a three year period
to implement the program plan.
This paper will present updated details of U.S. DOEs IPP program, the project structure and its objectives both short and longterm,
polymer tests and plications for LLW, ILW and HLW, and new product development initiatives.
2) OPERATIONAL EXPERIENCE WITH A COMMERCIAL PLANT FOR STABILISATION OF RADIOACTIVE
SLUDGE AND OTHER MATERIALS IN THE UNITED KINGDOM - 16042
Madoc Hagan, Rowland Cornell, Brian Riley, Nuvia Limited (UK);
Bryan Ware, UK Kingdom Atomic Energy Authority(UK)
In 2000, Nuvia Limited was contracted to design, build and commission a waste treatment plant (WETP) to stabilise the active
sludge stored in the External Active Storage Tanks (EAST) at UKAEA Winfrith, UK. <strong>The</strong> sludge was generated during the operational
period of the prototype Steam Generating Heavy Water Reactor (SGHWR), which is now in the process of being decommissioned.
This work supports UKAEA’s mission, which is to carry out environmental restoration of its nuclear sites and to put them
to alternative uses wherever possible. Recently UKAEA has been reorganised and responsibility for the site lies with Research Sites
Restoration Limited (RSRL) with funding provided by the Nuclear Decommissioning Authority (NDA).
<strong>The</strong> process of stabilisation of the SGHWR sludge from the EAST tanks within 500 litre stainless steel drums in the Winfrith
EAST Treatment Plant (WETP) using ordinary Portland cement (OPC) and blast furnace slag (BFS) is now almost complete. At
this stage it was planned to decommission and demolish the WETP facilities but RSRL have introduced a further stabilisation project
involving thorium metal waste ahead of the start of the planned decommissioning. As a result, the facilities are to be revised to
provide for the encapsulation of bars of thorium metal within modified 500 litre drums together with a number of necessary changes
to the plant control system.
3) THE DEVELOPMENT OF A METHOD FOR THE SIMULTANEOUS MEASUREMENT OF CERIUM (IV) AND
CHROMIUM (VI) SPECIES IN NITRIC ACID MEDIA - 16124
Ian D Nickson, John Tyndall Institute for Nuclear Research (UK); Colin Boxall, Lancaster University (UK);
Angela Jackson, Guy O.H. Whillock, National Nuclear Laboratory(UK)
<strong>The</strong> corrosion of stainless steel in nitric acid media is a major concern for the nuclear industry. Several reprocessing schemes
such as PUREX (Plutonium Uranium Reduction Extraction) and UREX (Uranium Reduction Extraction) utilise nitric acid media,
and an understanding of the behaviour of key chemical species in these process streams is vital if their effect on associated corrosion
reactions and their rates is to be accurately assessed and quantified. This will allow for more accurate prediction of the working
lifetime of any stainless steel surface in contact with the process stream in question.
Two such key species that are found in nuclear process streams are cerium as Ce (IV) and chromium as Cr(VI), both of which
may act as corrosion accelerants. <strong>The</strong> redox chemistry of cerium and chromium in highly active liquor (HAL) will depend on
nitrous acid concentration, temperature, acidity, total nitrate and possibly the influence of other dissolved species and hence an analytical
technique for the on-line measurement of these quantities would be useful for lifetime prediction and corrosion prevention.
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