via Fawley to a terminal on the far side of Southampton Water at Hamble, for export by tanker. Natural Gas (methane) is piped to Sopley, north of Christchurch, for use in the national domestic gas supply network. Smaller quantities of liquefied petroleum gas are transported by road. A rail terminal at Furzebrook connecting to the Swanage Railway between Corfe Castle and Wareham is now closed and mothballed. Production process plant The well fluids from the field and the remote well sites are combined at the gathering station. Oil is routed to the first stage separator where initial separation of the well fluids into its component parts takes place. Produced water settles to the bottom of the horizontal separator vessel, oil floats on the water layer and gas (vapour) occupies the top of the vessel. These three fluids are withdrawn continuously from the vessel to downstream plant. Oil flows to further separators operating at lower pressures, where further vapour and produced water are separated and removed. The oil then passes to a desalter to reduce the salt content. Fresh water is added to the oil and the oil-water mixture which is allowed to settle. The salt dissolves preferentially in the water phase reducing the salt content of the oil. Treated oil is cooled and stored in tanks before finally being pumped through the 16-inch (0.4 m) pipeline to the storage and loading facility at Hamble. The vapour from the separators is cooled, compressed and dehydrated by counter-current contact with glycol. It is chilled by refrigeration and routed to a series of fractionation towers. These include a de-ethaniser which separates the methane (CH4) from ethane (C2H6). There is a depropaniser to remove propane (C3H8) and a debutaniser to remove butane (C4H10). Some of the gases – the methane and ethane – are used as fuel gas on the site, the rest is compressed, odorised (with tertiary butyl mercaptan) and is routed via a 8-inch (0.2 m) pipeline to Sopley near Christchurch where it enters the National Gas Grid. Propane and butane (known collectively as LPG or liquefied petroleum gas) are maintained as liquids, they are odorised (with ethyl mercaptan) and stored in horizontal vessels on the site. LPG is sold and transported from the site by road tanker. Produced water from the separators is combined with treated site surface water and seawater and is injected into the reservoir via five wells. This