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Population's Awareness in Issues Associated with Nuclear Waste Repository
HÁKOVÁ, Veronika
The diploma thesis was elaborated on the topic of public awareness on issues related to the nuclear waste repository. The issue of nuclear waste management is currently being updated and increasingly discussed. Especially in connection with the search for a new site for the construction of a deep repository of nuclear waste and spent nuclear fuel. The aim of the thesis was to determine the level of knowledge of the population in the field of nuclear waste, its management, knowledge of the current nuclear waste repositories and the intended deep repository of nuclear waste and spent nuclear fuel and, last but not least, of ionizing radiation. The other task was to compare the level of knowledge of the inhabitants living in one of the sites of the intended underground repository (the Čihadlo site) and the inhabitants living outside this site. The following hypotheses have been established: "The level of knowledge on issues related to the repository for nuclear waste and spent nuclear fuel will be statistically significantly higher for residents living in the Čihadlo site than for those living outside that site" and "Knowledge on issues related to the nuclear waste repository and of spent nuclear fuel will reach at least 70% in both groups." A questionnaire survey was conducted to achieve the objectives set and verify the hypotheses. The results were evaluated using descriptive and mathematical statistics. The questionnaire consisted of 20 questions and 100 respondents from each site. The hypothesis has been confirmed that the level of knowledge of the inhabitants living in the Čihadlo site is statistically significantly higher. Knowledge on issues related to the repository for nuclear waste and spent nuclear fuel reached at least 70% for all respondents only on some issues. In the diploma thesis, there was a picture of the level of knowledge of the inhabitants about nuclear waste, its handling and storage of nuclear waste. The results obtained could be used as one of the bases in the site selection process for building a deep repository.
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The Cs-137 content in wild game
HÁKOVÁ, Veronika
The surrounding world has been influenced by ionizing radiation ever since. From the beginning they were only the natural sources as cosmic and solar rays or earth's radiation. Technical development of society brought discovery of artificial sources of ionizing radiation. In the beginning scientists studied them with noble aims. Eventually the negative side of utilization of nuclear fission was discovered in nuclear weapons. Artificial sources of ionizing radiation are mainly nuclear weapon's testing products from fifties and sixties in last century and nuclear power plant's accidents' products. When it comes to environment's contamination by Cesium radionuclide Cs-137 (further only Cs-137) and by inhabitants influencing, in The Czech Republic territory the biggest effect came from Chernobyl nuclear power plant failure. The aim of Bachelor Thesis is comparison of Cs-137 amount in meat of some species of forest or wild animals by semiconductor gamma spectrometry. The research question is whether amount of Cs-137 depends on animal species, or not. In The Thesis's introduction the general findings concerning ionizing radiation are described. What actually the ionizing radiation is and what a radionuclide and a half-life are. The next is a short set of quantities coming with ionizing radiation. Whereas the amount of Cs-137 in wild animal meat is examined, next part deals with Cesium and its isotope Cs-137. The amount of Cs-137 is very often compared with amount of natural Potassium K-40 (further only K-40) which is one of the most widely spread radionuclide in environment. Other part of The Thesis is devoted to nuclear weapon development. It actually began in between World Wars in the beginning of 20th century. The second most significant source of Cs-137 in our area was the crash of the 4th reactor of nuclear power plant Chernobyl, which occurred on April 26, 1986. By the way in this year has passed 30 years from one of the biggest nuclear catastrophe ever. In the next part a summary of wild animal species is given. Such animals were ahead selected and their meat was used as samples for measurement of Cs-137 mass activity. Mass activity was measured by means of semiconductor gamma spectrometry in Regional Centre of State Office for Nuclear Safety in České Budějovice. Due to availability of game animals was chosen Jindřichův Hradec region. Samples available for measurement reason were taken from the following kinds of hunting game: wild boar, fallow deer, roe deer, fox and hare. From each, under permission hunted piece was taken specimen of about 500 grams. After cleaning and cutting meat vas put to special Marinelli measurement bowls and frozen. Later was measured Cs-137 mass activity and for comparison also K-40 one. Measured values of Cs-137 mass activity oscillated from 1,9 Bq.kg-1 to 191 Bq.kg-1. In both cases it was meat of wild boar. Figures K-40 mass activity were from 47,4 Bq.kg-1 up to 201 Bq.kg-1. Where the lowest value came from meat sample of wild boar, then the highest value came from meat sample of roe deer. The numbers of Cs-137 and K-40 mass activities in meat sample of fox were almost the same. The mass activity values of any sample never reached the threshold value 600 Bq.kg-1, which is given by Announcement about radiation protection no. 307/2002 Sb. Measured values shows that amount of C-137 vary with the type of wild animals. According to statistic data the average game consumption is 700 grams per adult per year. In case of our family the consumption is even 7 200 grams per adult per year. Just for interest was calculated committed effective dose for consumption of 700 grams and also for estimated consumption of 7 200 grams. With consumption about 700 grams per adult per year the committed effective dose is 0,0017 mSv and with consumption about 7 200 grams is 0,018 mSv. The result is - effective dose values are not of great significance, contamination of hunting game meat by Cs-137 is
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