REGULATORY FRAMEWORK FOR PRODUCED WATER MANAGEMENT AT THE KAMENNY SUBSURFACE PETROLEUM SITE IN WEST SIBERIA

Abstract

The present study aimed to assess the safety in use of the Aptian-Albian-Cenomanian aquifer system within the Kamenny subsurface site, located in the West-Siberian petroleum region of Russia, when the produced waters resulting abundantly from oil extraction are injected thereto. The relevance of this study is necessitated by the need to dispose of produced waters (co-extracted with oil) within the Kamenny site, whose accumulated volume is currently estimated to be over 10,000 thousand m3. That said, the most important challenge facing the subsurface users is to minimize the adverse impact on the geological environment by water injection into the lost-circulation horizon and preserve the natural balance of the geological environment. This study has addressed the following problems: the natural geological-hydrogeological conditions of the Aptian-Albian-Cenomanian aquifer complex were assessed; the stability of hydrogeochemical measures of groundwaters was analyzed from the monitoring survey results (starting from the 1960s); the compatibility between the produced and reservoir waters was evaluated by estimating the carbonate balance of the system; and the stability of hydrogeochemical measures of the Atlym-Novomikhailovsk aquifer complex that holds fresh potable waters valuable for the drinking and domestic water supplies and overlies the Aptian-Albian-Cenomanian aquifer system. The solution found for each of the above-listed problems evidences the consistency of the hypothesis suggested herein that the Aptian-Albian-Cenomanian aquifer system is currently safe to use for the purpose of produced water (co-extracted with oil) injection. This paper also places emphasis on the necessity of continually improving the monitoring system for both the lost-circulation horizon and the overlying ones, and of scrupulously complying with all of the environmental safeguards, which is a mandatory prerequisite for retaining the natural balance of the subsurface resources of the West-Siberian petroleum region in Russia.