Teesside the four independent unitary authority boroughs of Hartlepool, Stockton, Middlesbrough and Redcar and Cleveland (a renamed Langbaurgh). At this time they were returned to the counties of North Yorkshire and County Durham for ceremonial purposes, with Stockton-on-Tees becoming the only district in England split between two ceremonial counties. In 1998 the neighbouring Borough of Darlington also became an independent unitary authority and this along with the four former Cleveland boroughs form the sub-region of the Tees Valley which is used for statistical purposes and governmental organisation. The name Tees Valley is increasingly promoted for economic and cultural connections, though Teesside,
Teesside Refinery to suspend refinery operations. The site will continue to operate as a terminal and storage facility.” On 24 January 2012 it was announced that Petroplus would file for insolvency, which led to the closure of Coryton Refinery. Teesside closed shortly afterwards and was bought by Greenergy in July 2012, reopening as a diesel, gasoil and kerosene supply depot in November 2012. Teesside Refinery The Teesside Refinery was an oil refinery and chemical plant situated just south of Seaton Carew on the River Tees in County Durham. In 2000, it was bought by Petroplus from ICI and Phillips Petroleum Company. Refining