RICHLAND -- Physicist Bob Runkle used a double-gloved hand to point to a landline telephone on a counter in a laboratory 30 feet underground.
"You won't see a speck of dust on that phone," Runkle said, his voice slightly muffled by a surgical facemask. "That is the cleanest telephone you'll ever see."
That's not the only unique thing the 16 college students of the Radiation Detection for Nuclear Security Summer School witnessed during a visit Wednesday to the Pacific Northwest National Laboratory's Shallow Underground Laboratory.
There were vats of acid "growing" copper wires finer than a human hair, and devices so sensitive to radioactivity that they only can be used in specially shielded spaces.
The lab tour is part of the students' two-week visit to the national laboratory. Researchers and scientists hope to nudge students into pursuing a career in nuclear security, which aims to prevent proliferation of nuclear weapons and enforce treaties banning their use.
Some students said they weren't fully aware of the laboratory's work or were wary of working in such a facility. That wasn't the case after they were out of their sterile clean suits and back above the surface.
"I'm in love with this place," said Hannah Gardiner, a senior physics student from Louisiana State University.
The underground lab and the summer camp program are relatively new at PNNL. The lab has been operating since 2010, and this is only the second year the summer camp has brought students to the north Richland campus.
Researchers use the lab to store and fabricate the materials they use to build highly sensitive radioactivity detectors. The detectors are used to analyze samples brought in for testing.
The lab's underground location eliminates background radiation that affects the earth from space. Ventilation systems remove radioactivity brought in from the surrounding soil. The scientists working in the lab wear, at minimum, clean suits with facemasks, hair nets and double layers of shoe covers and gloves.
"We're actually being pretty lax with you all," chemist Eric Hoppe told the students, noting they weren't required to seal their cuffs with tape or wear hoods.
Hoppe, Runkle and nuclear engineer Allen Seifert went over every aspect of the lab with the visiting students. Hoppe explained how the lab buys copper, which is about 99.999 percent pure, to use in the detectors. The metal is purified even more with acid baths -- costing thousands of dollars -- where trace radioactivity is removed and the copper reconstructed.
"We take copper we bought for $5 a pound, and by the time we're finished, it costs about $500 a pound," he said.
Seifert talked about how the detectors are built. One is used to test gas samples using a single fine wire and minimal amounts of plastic and other materials to reduce the possibility of dust coming to rest inside.
"If you get a single kink in that wire, it can wreck the accuracy of the detector," Seifert said. "You'll have to cut that detector apart and start all over again."
Runkle and Hoppe said the tour gives the students a taste of what researchers and scientists are doing in the field and the lab, instead of sitting in a classroom. It also shows the interdisciplinary nature of the lab's work -- engineers, chemists and physicists working together, using tools ranging from wrenches and lathes to microscopes and computers.
"The idea is to give them a real-life feel for the challenges," Runkle said. "Much more of it is hands on, getting your hands dirty. You can go to a lecture anywhere."
The cost of the program is paid for by the National Nuclear Security Administration, but students have to pay for their lodging and travel.
Some students said the subject of the program was outside their studies or pertained to work they hadn't planned on doing after finishing school.
"I do more nuclear astrophysics," Gardiner said. "This is kind of out of my element."
It didn't take long for that to change. Pat Mulligan, a 27-year-old nuclear engineering graduate student at Ohio State University, said he definitely is interested in working at the lab. He had been wary about working in isolated geographic areas, where nuclear labs usually are found.
Andrea Richard, a graduate student in nuclear physics at Ohio University, said her visit to PNNL was enlightening.
"I haven't even fully grasped what all you can do," Richard said after leaving the underground laboratory. "(The lab) opened it up so I could see what there is."
Hoppe said the camp does take time away from research, and there is a small risk that students visiting the underground lab could contribute to contamination. However, it's critical to get future scientists interested in the lab's work. It's also important they have first-hand exposure to its operations and the people who work there.
"You have to teach the next generation what you've learned and experienced," Hoppe said. "If you don't and you walk away, you're back at square one."
It's too soon to say how many, if any, of the visiting students will go on to careers in nuclear security. But they've at least attracted Gardiner's attention -- she's looking for an internship after she graduates next spring.
"I didn't know what I wanted to do with that year (after school), and now I do," she said.