Study On Cover Treatment And Stability Of Uranium Waste Rock Piles

For many years, in the uranium mine exploration course, our country has produced massive radioactive uranium mine scrap rock.. For the historical reason, the majority of scrap rocks is not at the government condition continuously. These uranium mine waste stone piles are affecting the local ecological environment and inhabitant's health seriously. So the uranium mine radioactivity waste stone pile retirement improvement of the geological system has become a urgent work.In this paper, the object of cover test is the KD-8 waste rock piles of xx mine of xx diggings. Three testing sites are chosen on the top surface of KD-8. The lateritic soil, humus soil and cinder are used as the cover materials to cover and stabilize these testing sites, respectively. The Radon-attenuation model is built on the basis of the double region diffusion theory with the simplified formula: , which is adapted to the multi-coverage systems and single-coverage system for calculating the radon release rate J_t for various cover thickness X_c. The resultsindicate that it is reasonable and feasible to use the formula to evaluate the project practice.The cover materials with different cover density and cover thickness were used to monitor the radon release rate and the gamma radiation dose rate, to analyze the effect and trend of cover density on the radon release rate and gamma radiation dose rate and to analyze the quantitative relationship between the cover thickness and the radon release rate.The three cover materials with certain density and 80cm thickness were used to cover the three testing sites, respectively. The plant is planted on the cover surface for spray test and root and penetrating fluid detection. The effects of the vegetation and precipitation in different cover materials on the infiltration and migration of the relative nuclides were investigated.The results show that the larger the cover density and thickness are the smaller the radon release rate and the level of gamma radiation, but there is a reasonable cover thickness. The radon difrusivity of the humus soil is greater than these of the lateritic soil and cinder, so its radon reduction is less effective. The meteorological parameters, such as wind speed, temperature, atmospheric pressure and others, have dissimilar impact on the radon release rate. The relative nuclides' absorbability of the vegetations and the rainfall penetration are slightly different and very small, which indicates that there is no potential radioactive harm to the vegetation and rainfall. There is a good stability of covering disposing uranium mine waste rock piles. The use of solid wastes as cover materials for the uranium mine radioactivity waste stone pile management presents an effective method for treating waste with waste.The research has positive guidance and reference for the uranium mine's decommissioning and disposal in our country.