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Ljubljana, Slovenia

Krizman M.J.,Slovenian Nuclear Safety | Rojc J.,Rudnik urana Zirovski vrh | Peter J.E.,Federal office for Radiation Protection
Nukleonika | Year: 2010

The term "radon event" indicates here a sudden appearance of enhanced radon concentrations, observed like well expressed peaks in time series of radon concentrations. The peaks are superimposed on normal diurnal periodical curves. The characteristics of radon events are high peak values, a rather short duration and a low radon equilibrium factor. Since radon events appear only in the environment near significant radon emission sources, they were investigated in more detail in the case of the former Žirovski Vrh uranium mine (Slovenia), using the existing network of continuous radon progeny measuring devices. Eight different types of radon events were identified in the vicinity of the U-mine disposal sites, lasting for some hours and with the range of their peak levels of equilibrium equivalent concentrations (EEC) of radon from a few Bq m-3 to over 200 Bq m-3. Exposures to radon events in units of Bq h m-3 were estimated for adult individuals of the reference group. They resulted in relatively high effective doses of the range 1-5 μSv per a single event, thus exceeding, e.g. the total effective dose for the public due to radioactive discharges from most nuclear facilities during the whole year. Source

Krizman M.J.,Slovenian Nuclear Safety | Rojc J.,Rudnik urana Zirovski vrh | Jovanovic P.,Institute of Occupational Safety of Slovenia
Nukleonika | Year: 2010

After cessation of the underground mining of uranium ore and production of uranium concentrate at Žirovski Vrh (Slovenia) in the period 1985-1990, two permanent surface disposal sites remained, namely, tailings pile and mine waste rock pile. Both disposal sites were of equal size of 4 hectares and were significant sources of radon. Their final restoration was designed in compliance with the condition of dose constraint for the public and authorized limits for radon exhalation from the remediated piles. In the late summer of 2008, a restoration of the mine waste pile was finished. Radon releases were reduced significantly by constructing an effective radon barrier of well compacted clayey material and a thick complex protective cover layer constructed over it. Radon exhalation rate from the mine waste area was lowered from primary level of 0.7 Bq/m2 s to natural levels (0.01 Bq/m2 s), and consequently, ambient radon levels also decreased on the site and nearby environment. The average radon contribution from the remaining U-mine sources was estimated on the basis of the environmental measurements of radon concentrations; they dropped from initial 7-9 Bq/m3 to approximately 3 Bq/m3. Further reduction of outdoor radon concentrations is expected after 2010, since the restoration of another disposal site will have been completed by the end of this year. Public exposure due to industrial radon after the first phase of restoration satisfactorily meets the dose constraint level of 0.3 mSv/y, since it decreased to less than 0.1 mSv/y. Source

Vaupotic J.,Jozef Stefan Institute | Kobal I.,Jozef Stefan Institute | Krizman M.J.,Slovenian Nuclear Safety
Nukleonika | Year: 2010

Radon (222Rn) activity concentration in outdoor air was measured by exposing track etch detectors at 60 points. Values were found in the range of 3.7-41.0 Bq·m-3, with a geometric mean (GM) of 11.8 Bq·m-3 and geometric standard deviation (GSD) of 2.2. An outdoor radon map of Slovenia was drawn, showing the majority of elevated values to be in the south-west part of the country that is covered by carbonates. Source

Kostadinov V.,Slovenian Nuclear Safety
Nuclear Engineering and Design | Year: 2011

The fundamental aim of an efficient regulatory emergency preparedness and response system is to provide sustained emergency readiness and to prevent emergency situations and accidents. But when an event occurs, the regulatory mission is to mitigate consequences and to protect people and the environment against nuclear and radiological damage. The regulatory emergency response system, which would be activated in the case of a nuclear and/or radiological emergency and release of radioactivity to the environment, is an important element of a comprehensive national regulatory system of nuclear and radiation safety. In the past, national emergency systems explicitly did not include vulnerability assessments of the critical nuclear infrastructure as an important part of a comprehensive preparedness framework. But after the huge terrorist attack on 11/09/2001, decision-makers became aware that critical nuclear infrastructure could also be an attractive target to terrorism, with the purpose of using the physical and radioactive properties of the nuclear material to cause mass casualties, property damage, and detrimental economic and/or environmental impacts. The necessity to evaluate critical nuclear infrastructure vulnerability to threats like human errors, terrorist attacks and natural disasters, as well as preparation of emergency response plans with estimation of optimized costs, are of vital importance for assurance of safe nuclear facilities operation and national security. In this paper presented new methodology and solution methods for vulnerability assessment can help the overall national energy sector to identify and understand the terrorist threats to and vulnerabilities of its critical infrastructure. Moreover, adopted methodology could help national regulators and agencies to develop and implement a vulnerability awareness and education programs for their critical assets to enhance the security and a safe operation of the entire energy infrastructure. New methods can also assist nuclear power plants to develop, validate, and disseminate assessment and surveys of new efficient countermeasures. Consequently, concise description of developed new quantitative method and adapted new methodology for nuclear regulatory vulnerability assessment of nuclear power plants are presented. © 2011 Elsevier B.V. All rights reserved. Source

Remskar M.,Jozef Stefan Institute | Gunde M.K.,Slovenian National Institute of Chemistry | Zeleznik N.,Agency for Radwaste Management | Kralj V.I.,University of Ljubljana | And 2 more authors.
AIP Conference Proceedings | Year: 2013

Slovenian female physicists have been organized in the «Neformalna Mreža Slovenskih Fizičark» (Informal Network of Female Physicists) since 2002. The network incorporates more than 120 women working in research, academia, government, and industry. In the last three years we have been active in promoting physics among young girls, educating the public on progress in nuclear science for peaceful use, public discussion on the situation of women in science, and distribution of the book Fizika, Moj Poklic (Physics, My Profession), published in 2007. We have a representative on the National Commission of Women in Science at the Ministry of Higher Education, Science and Technology. In the Commission we proposed a research survey with gender sensitivity on the current situation of researchers with PhD degrees, which was performed in 2010. Here we present the main results of this survey for respondents of both genders working in the natural sciences. © 2013 American Institute of Physic. Source

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