A case study of a gas-condensate field located on the northeastern shelf of Sakhalin Island demonstrates the possibility of development of condensate-containing gas reserves by drilling very long ERD wells (drilling from the shore). The development system described in the paper includes drilling well with upward orientation. Such design provides complete cleaning of a wellbore from fluids and solids accumulated over a long period of maintenance-free operation. The choice of a development system using horizontal wells is also associated with the geological structure of the field (massive type accumulation with a single gas-bearing contour is broken by tectonic faults into separate blocks with different hypsometric elevations). Under the technical, economical (drilling from platform and from land, the use of subsea production systems, ice gouging with hummocks), and environmental (presence of valuable fish species in water areas and permanent residence of indigenous peoples) limitations, the development of individual wells with vertical completions turned out to be unprofitable. For the first time for this type of accumulation located in a coastal zone, a unique method of monitoring the recovery of reserves within the cross-section, as well as movement of the gas-water contact without the use of monitoring and pressure observation wells was suggested.

Using BU161-4 formation of the Urengoy oil and condensate field deposit as an example the authors have demonstrated that today in the absence of developed transport infrastructure high CAPEX and OPEX investments are inevitable. It will result in negative economic results in developing oil banks in gas and condensate deposits located in the Northern and Polar regions of the Russian Federation. This factor decreases attraction of such assets for investors significantly and actually oil reserves in oil banks and gas reserves in gas caps are not developed and it is uncertain when these reserves might be developed. As a result the state will get less revenue from developing hydrocarbon reserves.

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