At emergency well No. 303 of the Karaturun East field, the second and final stage of remediation work is underway.


At emergency well No. 303 of the Karaturun East field, the second and final stage of remediation work is underway, according to experts in the oil and gas industry. The incident, which occurred on June 9, 2023, resulted from a violation of the technological regulations by the contracting organization Zaman Energo LLP, leading to the release of a gas-water mixture that subsequently escalated into an open gas-water fountain with subsequent ignition, reaching the highest level of complexity. This is due to the fact that emergency well No. 303 is located in a swampy area prone to active mudflows.

The complexity of the accident response is further exacerbated by the lack of wellbore data for well No. 303, particularly information on the location of the emergency wellbore below the 460-meter mark.

Initially, the decision was made by the Emergency Response Headquarters to develop individual technical projects for drilling two inclined-directional relief wells, No. 303-ST and No. 305-N, as well as vertical well No. 302.

On October 12, 2023, drilling of the inclined-directional well No. 305-N was completed at a depth of 1305 meters. Well 303-ST is being drilled towards emergency well No. 303 with the aim of intersecting the wellbores. Drilling of well No. 302 was completed on October 12, 2023, at a depth of 1220 meters. Perforation was performed on wells No. 302 and No. 305-N, and from October 13, 2023, a continuous daily water injection was carried out to flood the working gas reservoir and isolate it. As of November 20, 2023, over 40,000 m3 of water had been injected, significantly reducing the gas release from the emergency well, marking the concluding phase of the first stage of remediation.

After completing the drilling of well No. 305-N, wellbore surveys were conducted, gathering all necessary geological data about emergency well No. 303. Based on the studies, it was determined that two small gas horizons (Jurassic 1 and 2) with a thickness of no more than 2 meters are active. Consequently, the Emergency Response Headquarters decided to modify the planned depth of well 303-ST from 460 meters to 1040 meters to ensure the wellbore of 303-ST connects to the emergency wellbore of well No. 303 at a depth of 1040 meters (vertical depth). After connecting the wellbores, heavy drilling fluid will be injected through well 303-ST into the emergency wellbore of well No. 303, followed by cementing to completely stop gas emissions.

The injection of heavy drilling fluid is planned to commence no later than December 1, 2023. According to the Headquarters' estimates, this will constitute the second and final stage of the remediation efforts at the field.

Additionally, due to the modification of the planned depth of well 303-ST, the MBK-125 rig was promptly replaced with the more efficient ZJ-20 rig for conducting the required operations. To ensure the most secure and accurate connection of wellbores 303-ST and No. 303, Buzachi Oil Company has engaged high-precision telemetry equipment and acoustic and magnetic ranging systems, allowing the determination of the location of the emergency wellbore even without actual wellbore data.

Following the gas isolation and control of the water fountain, considering the upcoming measures for sealing the wellhead of the emergency well, the company plans to complete all accident remediation activities by the end of December 2023.

Media Contacts: Daniar Duisembayev, Deputy Director for Strategic Planning, Buzachi Oil LLP, Tel: +7 701 777 5858; Email: duisembayev@buzachineft.kz.