In the article the methods are considered related to the gas wells recovery in the conditions of the final stage of the Cenomanian reservoir development characterized by a hydrocarbons production decline due to a number of factors. These factors include the reservoir pressure drop, production water cut increase, degradation of development well stock and conversion of these wells to idle ones and further to their restoring repair. Based on the analysis of traditional workover methods and their low efficiency causes there were developed additional criteria, which indicate the necessity of improvement of the existing well workover methodology.

This article subject of study is a method of retrieving the stuck flexible pipe during the inactive well rehabilitation in the process of string side-hole drilling under the abnormally low reservoir pressure conditions. It is mentioned that the most common are methods using a flexible pipe which are related predominantly with the bottomhole flushing to remove clay-sand bridges, thawing the hole to eliminate hydrate-paraffin deposits, the bottomhole zone treatment with chemical compositions. It is emphasized that there is not enough experience of side-hole drilling using a flexible pipe and practically no experience of fishing with the help of flexible pipe.

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It is shown that the changed conditions of gas and gas-condensate fields operation entailed an increase in complexity of well repairs using coiltubing technologies. However, the methods developed for wells recovery in terms of emergency-refurbishment and water-influx restriction works are not provided for by the existing classification of complex well repairs which makes difficult to justify the length of repair works and, accordingly, their cost. The suggested amendments to the current structure of wells repair types promote further development of technologies of well workover in the conditions of oil and gas production decline .

Low-pressure gas production is one of the most important tasks in gas field development. To estimate the reserves of previously uninvolved reservoirs with low reservoir properties, it is necessary to analyze available geological and geophysical information for the subsequent creation of a three-dimensional geological model. Based on this model, a filtration model will be built, which allow calculating the flow rates of both actually drilled and designed wells for the entire development period. The model is built on the basis of small amount of information content, but the modeling results sufficiently reflect the presence of a zone of poorly saturated part of the Cenomanian gas reservoir, and structural and petrophysical features of the reservoir in the territory. As a result of the conducted research, the low pressure gas reserves at the Yamburgskoye field were calculated. The calculations, which are given in the article, are correct and don't contradict the Regulations on the creation of permanent geological and technological models of oil and gas and oil fields (RD 153-39.0-047-00).