Mathematical modeling of the stream and rate of the absorbed dose of radiation in various points over the surface of the sites polluted by radio-nuclides ( 40К and 226Ra) has been conducted. For this purpose, the mathematical model of the stream and rate of the absorbed dose of the radiation arising at various heights from the surface and on various distances from the central axis of conditional round-shaped site was calculated on the basis of program MATHCAD. Besides, pollution degree by a certain isotope for all points of the site was taken as identical. The area of local pollution, their degree and distribution on oil extracting sites investigated in model regularities established. On this basis, the model of radiation pollution was given. As a result of dosimetric measurements, it has been established that distribution of radiation pollution on oil extracting sites does not submit to any regularities, and their extent ranges from several decimeters to tens meters. Doses of an irradiation for workers of manufacturing areas on the sites polluted by radio-nuclides have been calculated as well.