Burla O. Evaluation of the level of ecological and radiation safety of oil producing territories

The thesis is devoted to the actual problem of evaluation and forecasting of the technogenic load in the oil producing territories, the source of which, mainly, is radioactive waste of drilling wells, formation water and oilfield equipment. The results of the work were approved and implemented. Based on the analysis of the content of radioactive elements in natural objects and oilfield equipment at the fields of the enterprise Okhtyrkanaftogaz, geological conditions and technology for their development have been established. In the operation of oil and gas fields, radioactive salts containing thorium and radium are deposited on pipeline equipment. The greatest environmental hazard in the problem of radioactive contamination is transportation and temporary storage of contaminated equipment. It has been established that radium and thorium are the most soluble in formation waters under acidic conditions, and in alkaline conditions they form solid solutions with barite (Ra) and goethite (Th), which allowed to suggest physico-chemical methods for cleaning equipment with acids. Passing a solution of HCl with a concentration of about 7% at a temperature of 25 °C leads to a complete leaching of thorium into the solution, a considerable dissolution of goethite, and a partial (about 10 %) extraction of radium. When the thickness of the crust of tumors on the walls of the tubing 1 mm already at low concentrations of silicic fluorosilicic acid (0.1–2%), practically all of Ra passes into the aqueous solution. The radiation impact of the Bugrivatove oil-producing complex on the environment is estimated, due to the removal of the industrial territory of the decay products of 238U. A technique for calculating the scattering of radioactive substances in atmospheric air is proposed, based on the Gaussian model using the loop attenuation factor due to the radioactive decay of the i-th radionuclide. Recommendations are given regarding the system of personal protection of personnel based on assessments of collective and individual doses of exposure.