sentences:  Around 1980 BNOC, who managed Plumley on behalf of the DoE, concluded that approximately £500,000 would need to be spent over a two-year period to keep it operational.In the early 1980s, as the DoE no longer required the storage of civil ground fuels for use in an emergency, the salt cavities were emptied of product, although they were retained as an asset for possible future usage.Cross-country skiing at the FIS Nordic World Ski Championships 2007
  
  Cross-country skiing was one of the three disciplines of the FIS Nordic World Ski Championships 2007, held between February 22 and March 4, 2007 in Sapporo, Japan.