In the late 1990s, a firm applied to the British Ministry of Defence for salvage rights to the Operation Deadlight U-boats, planning to raise up to a hundred of them. Because the U-boats were constructed in the pre-atomic age, the wrecks contain metals that are not radioactively tainted, and are therefore valuable for certain research purposes. The ministry awarded no salvage rights, due to objections from Russia and the U.S., and potentially from Great Britain.[5]