ExxonMobil’s proposed Longtail development project will tap into three gas fields—Longtail, Tripletail, and Turbot—spanning discoveries made in the period 2017-2019. Unlike Exxon’s previous developments in Guyana, which focus on crude oil, this project will center on non-associated gas and condensate production.
Longtail is expected to produce between 1 billion and 1.5 billion standard cubic feet of gas per day, along with 200,000 to 290,000 barrels per day of condensate, its project summary says. The project will include a floating production, storage and offloading (FPSO) vessel with a storage capacity of two million barrels of condensate. The FPSO will offload every three to five days.
The development will feature subsea infrastructure, including production wells, injection wells, manifolds, and production trees. Between 24 and 60 wells are expected to be drilled. Initially, the FPSO will process and re-inject gas to optimize condensate production, with infrastructure designed to enable gas exports once full re-injection is no longer necessary.
A map in Exxon’s project summary indicates that Longtail will be the easternmost development among the company’s offshore projects in Guyana. The project is designed for a 30-year production span, longer than the 20-year timeframe associated with ExxonMobil’s oil developments in the Stabroek Block.
ExxonMobil has requested an environmental authorization from the EPA to advance the project. However, in a public notice, the agency determined that the project is likely to have significant environmental effects and will therefore require an Environmental Impact Assessment (EIA). The EPA has invited public input on the scope of the assessment.
If approved, Longtail would be ExxonMobil’s eighth development in the prolific Stabroek Block. The company has secured approval for six oil projects, three of which are already producing: Liza 1, Liza 2, and Payara. The other three, Yellowtail, Uaru, and Whiptail, are set to start production in 2025, 2026, and 2027, respectively.
The seventh project, Hammerhead, is currently in the environmental authorization stage. The EIA for Hammerhead has been submitted and is under review by the EPA. ExxonMobil is expected to submit a field development plan (FDP) for the project this year to Guyana’s Ministry of Natural Resources, which, along with the EPA, will determine whether to grant a production license and environmental permit.
The same process will apply to the Longtail project. ExxonMobil expects to make a final investment decision (FID) on the Longtail project in 2026, with first production is targeted for 2030.
ExxonMobil operates the Stabroek Block with a 45% stake, alongside Hess (30%) and CNOOC (25%).
