[6] Sakhalin I's fields Chayvo, Arkutun-Dagi and Odoptu were discovered by the Soviets some 20 years before the Production Sharing Agreement of 1996.

The results were initially average from the appraisal wells with hydrocarbons being successfully tested, but there was still a large amount of uncertainty involved with the project.

However, in late 1998, a revaluation of the 3-D seismic data using the most advanced seismic-visualization techniques then available indicated that the hydrocarbon depth on the edge of the field could be significantly deeper than first thought.

[6][11] Production from Sakhalin 1 halted in May 2022, when operator Exxon Neftegaz declared force majeure at the project in response to international sanctions imposed on Russia after the Russian invasion of Ukraine in February.

In October 2022 Vladimir Putin instructed authorities to disband Exxon Neftegaz and transfer the project and all of its assets and equipment to a new operator, in which the government will hold a controlling 80% shareholding for an initial period of one month.

[12] By November the new operator of the project Sakhalin 1 LLC was owned 30% by Exxon Mobil, 20% by India’s Oil and Natural Gas (ONGC), 30% by Japan’s Sakhalin Oil and Gas Development (SODECO), Rosneft subsidiary Sakhalinmorneftegaz-Shelf who manages the project was given 11.5% and JSC RN-Astra 8.5%.

The total project is estimated to cost US$10–12 billion, making it the largest direct investment in Russia from foreign sources.

Approximately $2.8 billion has already been spent, which helped lower unemployment and improved the tax base of the regional government.

The fields are projected to yield 2.3 billion barrels (370×10^6 m3) of oil and 17.1 trillion cubic feet (480×10^9 m3) of natural gas.

[15] In addition, natural gas production for the peak winter season in 2007 was 140 million cubic feet per day (4.0×10^6 m3/d).

Although the rig is land based it will drill more than 20 extended-reach wells 10 kilometers (6.2 mi) horizontally out into the Sea of Okhotsk, and 2,600 meters (8,500 ft) in depth.

[1] As part of the project, Russia is in the process of building a 220-kilometre (140 mi) pipeline across the Tatar Strait from Sakhalin Island to De-Kastri oil terminal on the Russian mainland.

Scientists and environmental groups have voiced concern that the Sakhalin-I oil and gas project in the Russian Far East, operated by an ExxonMobil subsidiary Exxon Neftegas, threatens the critically endangered western gray whale population.

[20] Since 2006, the International Union for the Conservation of Nature (IUCN) has convened the Western Gray Whale Advisory Panel (WGWAP), consisting of marine scientists who provide expert analysis and advice concerning impacts on the endangered western gray whale population from oil and gas projects in the area, including Sakhalin-I.