Article provides a brief overview of the complications arising during the construction of oil and gas wells in conditions of abnormally high and abnormally low formation pressures. Technological properties of the solutions used to eliminate emergency situations when drilling wells in the intervals of catastrophic absorption and influx of formation fluid have been investigated. A technology for isolating water influx in intervals of excess formation pressure has been developed. The technology is based on the use of a special device that provides control of the hydrodynamic pressure in the annular space of the well. An experiment was carried out to determine the injection time of a viscoelastic system depending on its rheology, rock properties and technological parameters of the isolation process. A mathematical model based on the use of a special device is presented. The model allows determining the penetration depth of a viscoelastic system to block water-bearing horizons to prevent interformation crossflows and water breakthrough into production wells.

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Oil and gas resource production volumes in Russian fields are more confined to the development of areas discovered in the 70s-80s. According to their operation and development level, a depletion of reserves and a decrease in reservoir pressure are observed. The long time for development contributes to the complication of well construction conditions in these fields, especially in the matter of ensuring the reliability of separation of discovered reservoirs. The analysis of drilling and completion materials for fields in North Siberia and the Artic region showed that the absorption value of cement slurries during well attachment has increased, as well as the presence of inter-reservoir flows.

Nowadays, the decrease in number of urban areas for buildings is observed. Therefore, a novel construction of buildings has to be carried out in dense buildings areas. Construction buildings in historical districts become the most complicated goal. In order to preserve the cultural heritage, to ensure the safety of existing buildings and structures, and also safe building under, it is necessary to competently select the technology of digging pile foundations. Technological precipitation usually occurs at dynamic and vibration effects during the operation of equipment on the site and at pile construction. These effects cannot be analysed and depend on the quality of the work performed, the equipment chosen correctly and the technology applied. It is intended to eliminate the possible technological precipitation of buildings in the surrounding area by applying gentle technology-intensive operations. The article provides and systematizes defects that occur during CFA (Continuous Flight Auger), DDS (Drilling Displacement System), etc. The analysis of factors that influence on the appearance of defects has been made, and also the estimation of technologies from the preparation of wells when installing drilling and embroidery piles on the surrounding development in weak soils has been made.