Deep Underground Science and Engineering Laboratory

The Sanford Underground Research Facility (SURF), formerly Sanford Underground Laboratory at Homestake (or Sanford Lab) is an underground laboratory near Lead, South Dakota, which houses multiple physics experiments in areas such as dark matter and neutrino research. It was initially planned to be part of the United States Department of Energy's Deep Underground Science and Engineering Laboratory (DUSEL) project.

The Homestake mine in South Dakota was a deep underground gold mine located in Lead, South Dakota, and until its closure in 2002 it was the largest and deepest gold mine in North America.

Scientific experiments came to the mine in the late 1960s, when the Homestake experiment (also known as Davis experiment) was used by Raymond Davis, Jr. to observe solar neutrinos – this allowed him to discover the solar neutrino problem.

The Deep Underground Science and Engineering Laboratory, or DUSEL, was a major project under consideration by the research wings of the United States Department of Energy (DOE). DUSEL was planned to be a series of large laboratories, caverns, and cleanrooms serving the field of underground science. The main impetus for DUSEL was the study of extremely rare nuclear physics processes, like neutrino scattering, dark matter interactions, and neutrinoless double beta decay, which can only be studied in the absence of cosmic rays. (Cosmic ray muons on the Earth's surface cause backgrounds in these types of detectors, but the particles cannot penetrate great depths in rock.) Easy access to these great depths will open new frontiers in geomicrobiology, geosciences, and mining engineering, making DUSEL a multidisciplinary facility.

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