| Tolmount gas field | |
|---|---|
| Country | United Kingdom |
| Region | North Sea |
| Location/block | 42/28d |
| Offshore/onshore | Offshore |
| Coordinates | 54°02’24”N 00°26’24”E |
| Operator | Harbour Energy |
| Partners | Dana Petroleum, Harbour Energy |
| Field history | |
| Discovery | 2011 |
| Start of production | TBC |
| Production | |
| Estimated gas in place | 1,000×10 |
| Producing formations | lower Leman Sandstone |
The Tolmount gas field is a natural gas reservoir and production facility in the UK sector of the southern North Sea, about 36 km of east of Flamborough Head, Yorkshire. It is due to start production in 2022.
The Tolmount field extends over UK offshore Blocks 42/28c, 42/28d and 42/28e. The field was discovered in 2011 by well 42/28d-12 drilled by the Ensco 92.[1] The reservoir is a lower Leman Sandstone formation and has reserves of 1,000 billion cubic feet (bcf), 540 bcf in the main field, 220 bcf in Tolmount East and 150 bcf in Tolmount Far East.[2]
The Tolmount gas field is jointly owned by Dana Petroleum (50%) and Harbour Energy (50%), ODE Asset Management Limited operates the platform infrastructure.[3]
Production from the field will be developed in stages. In the first stage (Tolmount Main) gas is produced by an offshore platform and piped to Easington gas terminal.[4] Later stages will entail development of other parts of the field such as Tolmount East produced back to the platform.[5]
Details of the field infrastructure are as shown.[1][2][4][5][6]
| Platform name | Tolmount | Tolmount East |
|---|---|---|
| Installation type | Fixed Steel platform | Subsea wellhead |
| Coordinates | 54°02’24”N 00°26’24”E | 54°3'55"N 0°28'42"E |
| Function | Integrated minimum facilities wellhead and production | Wellhead |
| Crew | Not permanently attended | – |
| Year commissioned | 2021 | 2023? |
| Water depth, metres | 50 | |
| Design (FEED) | Wood Group | |
| Design and Construction | Rosetti Marino Ravenna Italy | |
| Jacket weight, tonnes | 2,350 | – |
| Topsides dimensions, metres | 32 x 34 | – |
| Topsides weight, tonnes | 1,456 | – |
| No. of legs | 4 | – |
| No. of well slots | 6 | – |
| No. of Wells | 4 | 1 |
| Gas processing capacity | 300 MMSCFD | – |
| Production to | Easington terminal | Tolmount platform |
| Pipeline length and diameter | 48.4 km, 20-inch | 4 km, 12-inch |
| Pipeline Number | PL4849 | |
| Methanol import | Piggyback on 20-inch line | Umbilical |
| Pipeline length and diameter | 48.4 km, 3-inch | 4 km, |
| Pipeline Number | PL4850 |
The gas pipeline is known as the Humber Gathering System. It is intended that other prospects in the area, e.g. Mongour, can use the system.[2]
In addition to the Tolmount offshore facilities a new gas process facility was constructed at the Easington terminal to receive and treat the gas prior to shipment into the National Transmission System.[2]
