Sandia National Laboratories
deep isolationthe company, founded in 2016 and headquartered in California, launched “Deep Well Demonstration Center” February 27. It is intended to show that getting rid of nuclear waste in deep boreholes is a safe and practical alternative to the shaft tunnels that make up most of today’s nuclear waste storage designs.
But while the initial board members were named at launch and a high-level plan released, the startup does not yet have a permanent location, nor funds committed to complete its planned drilling and testing program.
Although the idea of using deep wells to bury nuclear waste not new, no one has yet demonstrated how it works. The Deep Well Demonstration Center is intended to be a full-scale end-to-end demonstration, testing everything from the safe handling of waste canisters on the surface, disposal, eventual retrieval, and ultimately permanent sealing deep underground. Techniques will also be worked out to ensure that possible underground leaks do not contaminate the environment on the surface, even many millennia after disposal.
But it will do all of this without any real nuclear waste: “This place, to be clear, will never be used for radioactive waste disposal,” said Liz Muller, CEO of Deep Isolation and chairman of the board of the Deep Well Demonstration Center.
“This is to really bring people together to understand what are the main issues that need to be addressed before we move forward,” said Ted Garrish, the center’s executive director. “There is nothing really new here in terms of real technology; it’s just to put them together and do it in a nuclear environment.”
Universal canister
By the time of this announcement, the center’s first exercise in “combining” conventional oil drilling and nuclear technology had already begun. In February, a demonstration of the technology took place at a downhole test site near Cameron, Texas. “We need to have a fastening mechanism for this nuclear design container to attach it to a standard oil and gas rig,” Mueller explained.
They used a newly designed canister large enough to hold 14 feet of spent fuel. fuel assembly from pressurized water reactor (PVR). They snapped it on with standard oilfield equipment, lowered it through the floor of the rig, and unhooked it there. Later, they hooked on him again and fished him out again.
Funded by the US Department of Energy ARPA-E program Deep Isolation is developing a new universal container that can enter the well and receive waste generated during various reactor designs, not just PWR: “We’re talking to a number of different advanced reactor companies, what would their waste form look like, could we design it to fit in this versatile container?” said Mueller, who believes they should all fit in the same size canister as the PWR spent fuel canister used in the February test.
Decentralized recycling
The universal container should make deep wells suitable for various nuclear wastes, and the depth of the wells must be suitable for various places.
At the depth at which nuclear waste storage facilities are built (about 400 meters), there is usually quite a lot of flowing groundwater that can carry pollutants to the surface. Therefore, mined storage facilities for nuclear waste must be located in unusual locations where the rock is dense and the water is static to ensure that leaks in the storage facility do not go far, even after millennia. But going much deeper, Müller argues, waste can be deposited at depths where groundwater flow is typically minimal, so there are far fewer restrictions on suitable locations. “The geology is much more flexible than when you look at a booby-trapped vault,” Muller said. “When you go much deeper, when you go a kilometer, two kilometers deep, there are many more suitable places.”
This means that most locations where nuclear waste is generated have the potential to have deep well disposal facilities, reducing the need to transport nuclear waste to centralized facilities such as unsuccessful Yucca Mountain in Nevada. “We expect the first iterations of the deep containment technology to be implemented in existing waste treatment facilities,” Mueller said.
“I think if we’ve learned anything from trying to… consolidate locations and relocate [nuclear waste] in all states, I think the main lesson, big, big lesson for everyone: don’t do it!” Mueller said. Transportation of nuclear waste remains to this day cited as one of the objections State of Nevada to the Yucca Mountain Range.