First Homestake mine water pumped

LEAD - With the push of a button, mining technicians and engineers took a big step Friday morning toward converting the Homestake gold mine into an underground laboratory for science.

"At 10:18 a.m. we pumped the first water out of the mine," Sanford Underground Science and Engineering Laboratory director Dr. Jose Alonso said. Dr. Alonso made the announcement to the South Dakota Science and Technology Authority Board, which is meeting in Lead today (Friday). Minutes before, Dr. Alonso had been 1,250 feet underground in the Homestake mine, in a large, mined-out cavern, where he pushed a button that fired up a 700 horsepower electric motor, sending water to the surface.
The water was from a 300,000-gallon underground sump, but there was only a small amount of water in the sump. At 1,750 gallons a minute, the pump emptied it in five minutes.
Still, Dr. Alonso called it a milestone. "This was the most important button I've ever pushed in my life," he told the SDSTA Board.
Mining stopped at Homestake in 2001, and the mine, which is 8,000 feet deep, has been slowly filling with water since it was sealed shut in 2003 The water has risen to a level about 4,850 feet underground, where the science authority will build the Sanford Underground Laboratory. The Sanford Lab, in turn, will help demonstrate Homestake's feasibility for a national Deep Underground Science and Engineering Laboratory ("DUSEL").
Last year the National Science Foundation picked Homestake as the preferred site for a DUSEL, and a team of scientists received a $15 million grant to develop that proposal.
Dr. Kevin Lesko, the physicist from the University of California at Berkeley who is leading that team, said starting the pumping would be good news in the science community. "It's fantastic," he said. About 200 scientists from around the world are meeting in Lead from April 221through April 26 to discuss the first experiments at a Homestake DUSEL, and Lesko said they'll be able to see the progress firsthand.
The Sanford Lab at the 4850 level is a South Dakota-led project that could lead to underground experiments as soon as next year. The South Dakota Legislature approved $43 million for the la, and Sioux Falls philanthropist T. Denny Sanford donated $70 million to the project. The state also is using a $10 million federal grant to re-open the mine.
Greg King, director of operations for the Sanford Laboratory and a 30-year Homestake mine veteran, said today's test validated months of work. "When we started this enterprise last year the question was, can we re-enter the mine safely and pump water," he said. "This is one of the first proofs we can do that."
The next step will be to install and start the pump at the 2450 Level, where millions of gallons of water await. Dr. Alonso said that pumping could begin in early April. "This is excellent news," he said. Dr. Alonso said a pump and a 700 horsepower electric motor to power it had already been delivered to the 2450 Level. More than 3 million gallons of water are stored at the 2450 and 2600 Levels, so when that pump is turned on, water will begin flowing from the mine at a high rate.
The first water pumped from the mine in quantity will be stored in concrete reservoirs near the Yates shaft. From there it will be piped to the SDSTA's water treatment plant. The South Dakota Department of Water and Natural Resources has tested the mine water, which is not acidic and which is free of most other pollutants. The water likely will not have to be treated, but it will be filtered to remove suspended solids.
Greg King, director of operations for the Sanford Laboratory at Homestake, opens a gate valve 1,250 feet underground, in preparation for the first underground pumping since the mine was sealed shut in 2003.