engleski

Restoration of radioactively contaminated sites in the Republic of Croatia

In accorđance with the scope of work, which was presented and fundamentally accepted at the First Workshop in Budapest, there has been made some progress in the project implementation. Firstly, the highest priorities have been identified. They are related to two from four listed groups where higher radiation doses could be expected: [1] sites containing coallash piles (INA-VINIL plant in Kaštel Sućurac, coal-fired power plant PLOMIN) ; and [2] sites containing phosphates and phospho-gypsum remaining from fertilizer industry (INA-PETROKEMIJA in Kutina). The most sensitive site is INA-VINIL plant in Kaštel Sućurac, since there is (1) considerable population (some 250, 000 residents) living within radius of 10 km around the site ; (2) besides radiation there is adđitional, non-radioactive contamination generated by the plant (mercury, vinyl-chloride-monomer etc.) ; and (3) the site is situated at the seaside in close, densely populated Bay of Kaštela. Sampling and detailed measurements at all three sites are under way. At INA-VINIL plant in Kaštel Sućurac, where exist two coal slag- and ash dumps of some 10, 000 m2 in total, we are going to carry out sampling at grid 20 x 20 meters, i.e. to analyze about 30 samples (gamma-spectrometry above all). TLDs and GM probes will be set up on the site, and contamination will be measured during a period of some 6 months. In addition, the concrete as the final product of nearby cement factories in Kaštel Sućurac and Solin (where mixing of cement and coal-ash as a matrix is suspected) will be also inspected. Similar measurements are under way in the coal fired power plant PLOMIN. The site is situated close to the TUPJAK black coal mine wherein radon contamination is also foreseen to be measured {; ; ; since both Plomin and Kaštela sites were using mainly this coals). In INA-PETRDKEMIJA Kutina the samples of phosphates (raw-material), phosphoric acid, fertilizers (final products) and phospho-gypsum (waste material) have been already taken. They will be subjected to gamma-spectrometry, along with the air samples from the phosphoric acid plant. Radiochemical analysis (~6Ra) will be done at water samples (from piezometers) and wells in surrounding populated area. Working level {; ; ; for ~Rn daughters) is also foreseen to be done. TLDs and "diffusion chambers" were set up at đesired places. Besides previously involved , Institute "Ruđer Bošković", another institution ; i.e. the Institute for Medical Research and Occupational Health from Zagreb has been included into the project. Unfortunately, due to lack of needed funds we are meeting some obstacles in the project evolution in terms of the proposed (time) schedule. Nevertheless, it is realistic to expect final decisions on necessity and - if needed - modes of additional protection measures at the sites, or even removal of contaminated material to more convenient areas by the end of 1994. It is worth mentioning that we are simultaneously running the project of site selection of radioactive waste repository in Croatia, and few preferred (candidate) sites are supposed to be identified and verified up to the end of the year. Namely, it is supposed that some of contaminated materials involved in the project, will be eventually disposed at our radioactive waste repository.

-radioactivety contaminated; remediation

IAEA = International Atomic Energy Agency ; TECDOC = Technical Document