Wikipedia
The Sakhalin-I project, a sister project to Sakhalin-II, is a consortium to locate and produce oil and gas on Sakhalin Island and immediately offshore, in the Okhotsk Sea, from three fields: Chayvo, Odoptu, and Arkutun-Dagi.
In 1996, the consortium completed a production-sharing agreement between the Sakhalin-I consortium, the Russian Federation, and the Sakhalin government. The consortium is managed and operated by Exxon Neftegas Limited (ENL).
Since 2003, when the first Sakhalin-1 well was drilled, six of the world's 10 record-setting extended reach drilling wells have been drilled at the fields of the project, using the Yastreb rig. It has set multiple industry records for depth, rate of penetration and directional drilling. On 27 August 2012, Exxon Neftegas Ltd beat its previous record by completing Z-44 Chayvo well. This ERD well reached a measured total depth of , making it the longest well in the world.