SNOLAB

SNOLAB is a Canadian underground physics laboratory at a depth of 2 km in Vale's Creighton nickel mine in Sudbury, Ontario. The original Sudbury Neutrino Observatory (SNO) experiment has ended, but the facilities have been expanded into a permanent underground laboratory.

Although accessed through a mine, the laboratory proper is maintained as a class-2000 cleanroom, with very low levels of dust and background radiation.

SNOLAB is the world's second-deepest underground lab facility; its 6,800 feet (2,070 m) overburden of rock provides 6010 metre water equivalent (MWE) shielding from cosmic rays, providing a low-background environment for experiments requiring high sensitivities and extremely low counting rates.

The Sudbury Neutrino Observatory was the world's deepest underground experiment since the Kolar Gold Fields experiments ended with the closing of that mine in 1992. With the deepest underground laboratory in North America at 2100 metre water equivalent depth, and the deepest in the world at 4800 m.w.e., many other groups were interested in conducting experiments in the 6000 m.w.e. location.

In 2002 funding was approved by the Canada Foundation for Innovation to expand the SNO facilities into a general-purpose laboratory, and more funding was received in 2007 and 2008.

Construction of the major laboratory space was completed in 2009, with the entire lab entering operation as a 'clean' space in March 2011.

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