Finding a Site

Notre Dame’s involvement with SURF has its origins in a facility called the Deep Underground Science and Engineering Laboratory (DUSEL), planned by the National Science Foundation (NSF) as a complex of laboratories for research in multiple fields: biology, chemistry, geology, as well as physics.

Notre Dame researchers were especially interested in one aspect of the DUSEL concept called DIANA (Dual Ion Accelerators for Nuclear Astrophysics). And with good reason, according to Robert J. Bernhard, the University’s vice president for research. “The nuclear astrophysics community identified DIANA as a priority, and identified Michael Wiescher to lead that facility,” Bernhard said.

Wiescher, the Freimann Professor of Nuclear Physics at Notre Dame, led the planning for the DIANA portion of the NSF proposal. That is, right up until sequestration of federal spending made funding of the project impossible. The NSF would eventually ask Wiescher and Notre Dame to withdraw the DIANA proposal, with hopes of one day revisiting it.

“So the question was, do we just drop it, or do we move ahead?” Wiescher recalls. “And we decided to move ahead, with a smaller scale version.”

Moving ahead with a smaller project allowed the NSF to still be involved, while a coalition of other partners was formed, including the South Dakota School of Mines and Technology, and Colorado School of Mines. The collaborative nature of CASPAR is indicative of a trend in scientific research at large, and especially at Notre Dame, according to Bernhard. For its part, Notre Dame is strategically investing in labs and equipment that serve multiple researchers and collaborative programs.

”Instead of buying equipment for individual labs, we’re directing funding in high performance, shared facilities such as the integrated imaging facility, the center for nano research and technology, the genomics and bioinformatics facility, the mass spectrometry and proteomics facility,” Bernhard said.

That same philosophy is at work at SURF, which, like CASPAR, has its own indirect path to realization. The Homestake Mine was founded after an expedition led by George Armstrong Custer discovered gold in South Dakota’s Black Hills in 1874. Five years later, the Homestake Mining Company began operations, eventually carving out 370 miles of tunnels as deep as 8,000 feet, creating one of the deepest mines in the country. The gold vein was eventually exhausted after producing 1.25 million kilograms of gold in its lifetime (roughly $80 billion at today’s rates), and Homestake shut down in 2001.

The closing of Homestake resulted in an economic and identity crisis for Lead and the surrounding area. However, in addition to its gold mining past, Homestake had a unique astrophysics connection.

The Sanford Underground Research Facility in Lead, South Dakota still bears the Homestake moniker. A hoist drum spooling more than 5,000 feet of steel rope lifts and lowers the elevator in the mine shaft. The Compact Accelerator System is modular, to allow for transport down the mine shaft. A section of the CASPAR system. Another portion of the Compact Accelerator System used in CASPAR.

In 1965, Ray Davis, a nuclear chemist from Brookhaven National Laboratory, began building an experiment deep in the Homestake mine with the goal of counting neutrinos, subatomic particles produced in fusion reactions inside stars. In 2002, Davis was awarded a share of the Nobel Prize for Physics for his neutrino work at Homestake.

When Homestake announced it would close the mine, physicists, aware of Davis’ neutrino success, proposed converting it into a deep underground laboratory. In 2004, the South Dakota Legislature created the South Dakota Science and Technology Authority (SDSTA) to work with the scientists proposing the lab. In 2006, Homestake Mining Co. donated the underground mine to the SDSTA. Also in 2006, the SDSTA accepted a $70 million gift from South Dakota philanthropist T. Denny Sanford, who stipulated that $20 million of the donation be used for a Sanford Science Education Center.

Then the real work began, according to Ani Aprahamian, Notre Dame’s Freimann Professor of Experimental Nuclear Physics and a member of SDSTA’s board.

“When you have a mine, it’s just people going under to dig at the rock. It’s dirty, filthy,” Aprahamian said. “This is a laboratory that requires a high level of cleanliness, underground. It’s a little bit more than just building a scientific lab, like you would above ground. So the transformation was quite astounding.”

The first step in that transformation was to pump millions of gallons of water out of the tunnels of the old mine. That task took months. Then came the installation of the power and technology infrastructure required in the roughly 4,400 square feet occupied by CASPAR. Meanwhile, the group of Notre Dame astrophysicists had to devise a way to disassemble and move an accelerator that had been on campus for 10 years to its new underground home.

“We worked in conjunction with the team at SURF so that everything we designed and built at Notre Dame was modular,” said Robertson. “The idea was that we could dismantle every section and bring it down in much smaller pieces and rebuild it from scratch. We packed it all up into two U-Haul vans and dragged it all the way from campus to SURF.”

When it arrived, the equipment was brought down the mine shaft via infrastructure originally designed to move men and minerals, not highly sensitive scientific equipment. Robertson recalls the series of roughly two-mile trips from the surface to the underground lab taking upwards of 45 minutes because of the pace at which the conveyances had to travel with accelerator parts on board.