No abstract

Tengizchevroil (TCO) has had up to 20 years of experience in industrial Waste Water Disposal (WWD) into the subsurface. TCO industrial waters cannot be recycled or utilized for any other purposes, hence, malfunction of any component of WWD system (especially wells) can lead to production curtailment. Therefore, TCO has identified the WWD wells as "critical" wells in the business unit. Waste water is injected into three disposal wells; there are six monitoring wells that provide important information about reservoir pressure, the change in chemical composition of water samples, the fluid level and wellhead performance. Regular surveillance is a key to get data, such as reservoir pressure, temperature, downhole samples, reservoir connectivity, etc. This is important to build the correct reservoir model, both static and dynamic with immediate interest in identifying the water front movement and eventual water breakthrough wells. In the light of expected operational activities, optimization projects and commercial oil growth, WWD activities are planned to be expanded. Drilling new wells is proposed to add spare injection and monitoring capacity to the project. Additional services, surveillance steps, well geometry and completion design optimization is considered for all new wells. Cross-functional efforts of subsurface earth scientists and petroleum engineers, lab technicians/facility engineers/environmental specialists/regulatory teams are critical to achieve technical excellence, and hence to fulfil regulatory requirements. Third party involvement in lab analyses and results interpretation strengthens confidence in the operator's efforts to maintain and protect the environment according to official agencies vision.