SURF completes first phase of expansion for underground research space

The Sanford Underground Research Facility (SURF) has completed the first phase for a major expansion of new research space nearly a mile below the surface.

“This important milestone puts SURF one step closer to the expansion of high-value research space that will attract world-leading underground science for decades to come,” said Mike Headley, executive director of the South Dakota Science and Technology Authority (SDSTA) and the laboratory director at SURF. “Thanks to the state of South Dakota for funding this expansion phase and thanks to the dedication of everyone involved in this project, including our contractor, Thyssen Mining, for their incredible efforts.”

The new access tunnel, called a drift, will lead into two large caverns intended to house future generations of cutting-edge underground research. The access drift is the first phase of the expansion that began in May of this year. Phase two, which includes the larger caverns, is expected to commence around 2028 and take 2-3 years to complete.

Blasting drifts into solid rock underground is a highly controlled and carefully engineered process. Thyssen Mining Incorporated (TMI), completed the phase one expansion utilizing precision blasting and excavation. All rock excavated from SURF for this first phase of the expansion remains underground.

This video shows a time-lapse of the process of blasting, mucking, marking, drilling, loading the charge, and blasting again. TMI crews safely completed this cycle many times over the summer months to finish this phase of the expansion. Brent Knottnerus, a project engineer for SURF, helped lead the effort. He gives praise to TMI for their perfect safety record, ability to stay on schedule and budget, and excellent product.

“TMI has been an exceptional partner and a high-caliber contractor in this project,” Knottnerus said. “They brought a can-do attitude to the job. If we ran into a challenge, they responded right away with a solution. Most importantly, they completed this job safely, on time, on budget, and with the highest quality work.”

Skyler Pearson, a project manager at TMI, helped lead the project and credits teamwork from all involved.

“The work the crew did here was absolutely amazing. If you walk down the bypass drift, the quality of the final product is excellent. They took a lot of pride in their work, and it shows,” Pearson said. “Our success here is also thanks to the cooperation from our partners at SURF who trusted us to get the job done,” he added.

The expansion further establishes SURF as the world’s preferred location for underground science this century. The Deep Underground Neutrino Experiment under construction a mile underground at SURF is expected to be in operation through the first half of this century. The new expansion laboratory opens opportunities for research that could last well into the 2060s or 2070s.