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

Abstracts Session 35
Functionally, the methods for addressing contamination must remove and/or reduce transport of contaminants. This problem
is particularly challenging in the arid western United States where the vadose zone is hundreds of feet thick, rendering transitional
excavation methods exceedingly costly and ineffective. Delivery of remedial amendments is one of the most challenging and critical
aspects for all remedy-based approaches. The conventional approach for delivery is through injection of aqueous remedial solutions.
However, heterogeneous deep vadose zone environments present hydrologic and geochemical challenges which limit the
effectiveness. Because the flow of solution infiltration is dominantly controlled by gravity and suction, injected liquid preferentially
percolates…
3) MOBILITY OF RADIUM FROM PYRITIC URANIUM MINE TAILINGS UNDER
SUB-AQUEOUS DISPOSAL CONDITIONS (wP-59283)
Nand Dave, Mining and Mineral Sciences Laboratories Canada (Canada)
All uranium mines in the Elliot Lake uranium mining district of north-central Ontario, Canada, have been closed due to low
ore grade and prevailing market conditions. A majority of the waste management facilities have been rehabilitated and decommissioned
with in-situ shallow water covers to minimize sulphide oxidation, and hence acid generation and release of metal enriched
effluents.
Laboratory lysimeter investigations were undertaken to evaluate the leaching characteristics and mobility of Ra-226 and other
heavy metals (U, Th and Pb) from pyritic uranium mine tailings under sub-aqueous disposal conditions for assessing the long-term
radiological stability of such waste repositories. The experiments were conducted using three types of un-oxidized tailings: coarse,
fine and gypsum depleted mill total tailings. Shallow water covers of depth ~ 0. 3 m were established using natural lake water. The
leaching characteristics of radium and other major and trace metals were determined by monitoring both surface and pore water
qualities as a function of time.
The results showed that Ra-226 is leached from surface of the submerged tailings and released to both surface water and shallow
zone pore water during initial low sulphate ion concentration of the surface water cover in all three cases. The release of Ra-
226…
4) REMEDIATION PROJECT PLANNING AT THE URANIUM PRODUCTION LEGACY SITES.
LESSON LEARNED FROM THE BEST INTERNATIONAL PRACTICE AND CHALLENGES
FOR DEVELOPING COUNTRIES (wP-59043)
Oleg Voitsekhovych, Ukrainian Hydrometeorological Institute (Ukraine)
The former Soviet Union countries such as Kazakhstan, Kyrgyzstan, Russia, Tajikistan, Uzbekistan and Ukraine, where uranium
production legacy sites are located (such as mines, waste rock piles, pits, chemical and hydrometallurgical plants, tailing
dumps, etc.) are currently facing the challenge of making these objects environmentally safe. These countries share a common history
of the uranium mining and milling industry, similar regulatory shortcomings and uncertainties regarding the strategy justification
for such remediation projects. They also have to deal with scarcity of financial resources for long-term remediation programmes,
and lack of experience with planning and management of environmental remediation projects at former uranium production
sites.
In the recent years, IAEA-supported programmes of international technical co-operation (the projects RER/0986 and
RER/3010) were advancing actively, as well as those sponsored by the UNDP, EurAsEC and others, all aiming to assist with the
preparedness and performance of future remediation projects. As demonstrated by analysis, effectiveness of the many programmes
largely depends on the nations’ level of preparedness to carry out remediation projects in accordance with the international standards.
The lessons learned from analyses of the different type of projects, which were already implemented or which are still in plan
in different countries and in particular…
5) CLOSE-OUT OF OPEN PIT AND WASTE ROCK PILES OF DAXIN URANIUM MINE OF CHINA (wP-59073)
Lechang Xu, Changshun Ren, Min Shi, Liaoning Xueli Zhang,
Jie Gao, Beijing Research Institute of Chemical Engineering and Metallurgy, CNNC (China)
Daxin Uranium Mine is an small open pit mine. Its contaminated facilities include open pit 87620m2 , East waste rock pile
71710m2 , west waste rock pile 57828m2 , ore transfer station and industrial fields 9370m2 , building and structure 26600m2 , equipment
246 pieces, plastic conduit 3000m. steel conduit 2500m2 and road for transporting ores 1020m. The integrated decommissioning
programmes are presented: uranium extraction, slope stabilization, clear-up, backfill, reshape, covering, re-vegetation, dismantlement/demolishment,
decontamination, re-smelting, waste water treatment.
SESSION 35 — (MERGED WITH SESSION 34)
SESSION 36 — RADIUM REMEDIATION: HISTORICAL PERSPECTIVES
AND CURRENT CIRCUMSTANCES - PART 1 OF 3 (4.11)
1) RADIUM DIAGNOSIS CAMPAIGN (wP-59327)
Florence Gabillaud-Poillion, Autorité de Sûreté Nucléaire (France)
In line with the approaches already adopted in France during the 90s on various sites where research and/or radium-extraction
activities were mostly conducted in the past, the French public authorities wish from now on to pursue their prevention and siterehabilitation
approach inherited from the French craftsman and medical sectors that used that radioelement.
As a matter of fact, radium has been in use in several medical activities, notably in the initial methods of cancer therapy. Similarly,
it was also used in some craftsman activities, such as the clock industry, for its radioluminescent properties, the fabrication
of lightning conductors or cosmetics until the 60s. Those activities have generated various traces of pollution that have remained
today.
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