Frequently Asked Questions

About neutrinos

What is a neutrino?
Why is the LBNF/DUNE project scientifically important?
Are neutrinos safe?
Will the neutrino beam be safe?
How do you make neutrinos?
What path will the neutrinos take from Fermilab to Sanford Lab?
Will the neutrinos affect people’s property?

About activities at Fermilab

Has Fermilab done similar projects previously?
Does the neutrino-making process at Fermilab produce radiation?
What would be constructed at Fermilab?
When would construction at Fermilab begin?
Would construction at Fermilab affect neighbors?
Would operation of the facility at Fermilab affect neighbors?

About activities at Sanford Lab

What would be constructed at Sanford Lab?
When would construction at Sanford Lab begin?
Would construction at Sanford Lab affect neighbors?
Would operation of the experiment at Sanford Lab affect neighbors?

More information

Where can I find out more about the environmental assessment of the LBNF/DUNE project?
How will you keep the public informed?
Where can I find out more about the project?

What is a neutrino?

Neutrinos are harmless particles that are among the most abundant — yet least understood — in the universe; they are a billion times more abundant than the particles that make up stars, planets and people. These tiny particles have no electric charge and mostly pass right through the atoms that make up ordinary matter, very rarely interacting with it. Therefore, not only are they harmless, but very challenging to observe!

Experiments carried out over the past half century have revealed that neutrinos are found in three states, called flavors, and can transform from one flavor into another. These discoveries have put neutrinos in the spotlight for further research into several fundamental questions about the nature of matter and the evolution of the universe.

Why is the LBNF/DUNE project scientifically important?

Neutrinos, created in vast numbers just after the Big Bang, are crucial to understanding the origins of our universe, as well as energy and matter. Neutrino experiments are already helping to answer many important questions, and DUNE is planned as a world-leading, next-generation experiment capable of measuring neutrino parameters that will significantly advance our understanding. DUNE may find, for example, that neutrinos are the key to solving the mystery of how the universe came to consist of matter rather than antimatter. LBNF will provide the neutrino beam for this experiment and the facilities to house and support it.

In addition to studying neutrinos from the beamline at Fermilab, the DUNE detector is being designed to catch neutrinos emerging from exploding stars (supernovae) allowing us to peer inside a star as it dies and collapses into a black hole. Scientists also will use the DUNE detector to look for rare subatomic interactions predicted by theories inspired by Albert Einstein’s search for a Grand Unified Theory.

Scientists from around the world consider the scientific goals of the LBNF/DUNE project among the most important research efforts in particle physics, rivaling the discovery of the Higgs particle at the Large Hadron Collider in Europe in 2012.

Are neutrinos safe?

Yes. Neutrinos do not emit radiation, nor do they affect matter — hence the difficulty in observing them. Neutrinos are all around us: Each second, more than a trillion neutrinos from the sun, traveling close to the speed of light, pass through your body without any effect. Fermilab has operated neutrino-producing facilities for more than 30 years. Over the last 10 years, the laboratory has been sending neutrinos harmlessly from Fermilab through the ground to research facilities in Minnesota.

Will the neutrino beam be safe?

Yes, it will be completely safe. Unlike a focused beam of light that can heat and potentially burn objects, neutrinos neither create heat nor change the properties of the material they travel through. Unlike a laser beam, the neutrino beam will spread as it travels. By the time the neutrinos reach South Dakota, the neutrinos will be dispersed into a cone about 50 miles wide.

How do you make neutrinos?

For the LBNF/DUNE project, scientists will use one of Fermilab’s existing particle accelerators, the Main Injector, to make neutrinos. This machine has made neutrinos for other experiments at Fermilab since 2004. It accelerates protons, and smashes them into a piece of graphite or similar material where they collide with atoms in the material, producing secondary particles. The particles that emerge from these collisions generate neutrinos. Watch this short video that explains the neutrino-making process.

What path will the neutrinos take from Fermilab to Sanford Lab?

Neutrinos travel in a straight line. Since the Earth is round, Fermilab plans to point the neutrinos at an angle into the ground and send them in the direction of the particle detector at Sanford Lab. The neutrinos will leave the Fermilab site at a depth of about 200 feet, cross about 10 miles deep underneath the Mississippi river and reach a maximum depth of close to 20 miles as they travel to South Dakota. No tunnel is necessary to send the neutrinos from Fermilab to South Dakota since neutrinos can travel straight through rock!

Will the neutrinos affect people’s property?

No. The neutrinos will not affect the rock, soil, water or anything else they travel through.


Has Fermilab done similar projects previously?

Yes. Fermilab built similar infrastructure for the Fermilab-to-Minnesota neutrino project in the early 2000s, and Fermilab has built and operated particle accelerators for more than 40 years.

Does the neutrino-making process at Fermilab produce radiation?

Yes. The neutrino-making process creates very short-lived particles that decay quickly and small amounts of tritium, a weakly radioactive form of hydrogen with a half-life of 12.3 years. These byproducts are created when the primary proton beam strikes the piece of graphite, and they are trapped by the surrounding rock. These lifetimes are much shorter than the million-year-long lifetimes of some of the radionuclides produced at nuclear reactors. Fermilab has no nuclear reactors or other nuclear facilities, and thus produces none of the radionuclides with million-year-long lifetimes.

Radionuclides created by our particle accelerators rapidly decay into lighter particles until everything has been transformed into stable atoms and electrons. For many types of radionuclides, this takes only hours; for others, such as tritium, it takes years. The small amount of energy (radiation) produced in the decay of these particles gets absorbed as a small amount of heat by the concrete shielding surrounding the area in which these particles are produced.

Fermilab has safely operated particle beams and neutrino-making facilities at Fermilab for more than 30 years. The proposed LBNF/DUNE facility would be similar to existing ones.

We have a website that we use to post our latest tritium measurements to keep our neighbors informed about the low levels of tritium produced at Fermilab and the low levels of tritium that can be found in surface waters on the Fermilab site.

What would be constructed at Fermilab?

Scientists propose the construction of four buildings, a 58-foot-high hill made of compacted soil, a 680-foot-long tunnel on the Fermilab site that would house the equipment to make the neutrinos, a 635-foot-long particle decay pipe, two approximately 200-foot-deep access shafts and an underground hall that would hold a particle detector on the Fermilab site. All of this would be located in the western area of the Fermilab site, close to Kirk Road in Batavia, Illinois. One of the buildings, about 50 feet wide, 135 feet long and 40 feet high, would be constructed close to Giese Road and Kirk Road in Batavia, on the Fermilab site. The buildings on top of the shafts would provide access to underground halls. See this graphic for the overall layout of the facility at Fermilab.

When would construction at Fermilab begin?

Construction at Fermilab could start as early as 2018; the actual start of construction is dependent on U.S. Department of Energy approval and how soon funding would become available.

Would construction at Fermilab affect neighbors?

Some parts of the construction could affect neighbors living close to the construction site. There would be construction noise, and residents living very close to the construction site might notice vibration associated with the blasting that is necessary for the construction of the approximately 200-foot-deep shaft and underground hall near Kirk Road and Giese Road. The construction of the shaft will require blasting several times per day for about 14 months. Fermilab will work with contractors to minimize the impact on its neighbors. Since the blasting could lead to noticeable vibration levels in nearby houses, Fermilab plans to offer pre-construction surveys of nearby homes and will consider installing noise and vibration monitors in the residential area across the construction site.

The construction of the entire Fermilab portion of the facility is expected to occur in two phases over about seven years, with a one-year gap between phases. The first phase is currently planned to begin in 2018 and last about 18 months. The second phase would begin in 2021 and last about 4.5 years.

Would operation of the facility at Fermilab affect neighbors?

No. Operation of the new facility would be similar to the operation of existing facilities at Fermilab. Operational noise impacts would be low and limited to chillers and air handling equipment.


What would be constructed at Sanford Lab?

At the Sanford Lab (Sanford Underground Research Facility, SURF), scientists would build one service building on the surface and three large underground caverns on the 4850-foot level of the existing facility. Construction would require the excavation of approximately 530,000 cubic yards of rock from underground areas. The new underground caverns would hold a large particle detector modules filled with liquid argon, a material similar to helium, but heavier.

When would construction at Sanford Lab begin?

Construction at the Sanford Underground Research Facility could start as early as 2017 if approved by the Department of Energy and funding becomes available.

Would construction at Sanford Lab affect neighbors?

Rock transport by truck would require an average of 75 round trips per day and is expected to last for 35 months. Traffic would substantially increase on Kirk and Gilt Edge Roads in Lead, South Dakota, if the trucking alternative were to be used. The construction at Sanford Lab would be mostly underground. Aboveground construction of a building would result in temporary noise increase, including noise from trucking along the transportation routes.

Would operation of the experiment at Sanford Lab affect neighbors?

No. Operation of the LBNF/DUNE experiment would be similar to the operation of existing experiments at the Sanford Underground Research Facility. No radiation will be produced by the experiment at the Sanford facility. Operation of the Cryogen Support Building would increase noise slightly above existing nighttime ambient noise levels around the Ross shaft complex.


Where can I find out more about the environmental assessment of the LBNF/DUNE project?

With the help of a number of technical experts, including independent consultants, the Department of Energy (DOE) has prepared an Environmental Assessment document for the LBNF/DUNE project, including the investigation of potential impacts to human health and the environment. The DOE initiated the environmental assessment in May 2013 and released the draft environmental assessment in June 2015 for public comment. Public meetings were held in Illinois and in South Dakota. In October 2015, the DOE issued the final environmental assessment and determined that the LBNF/DUNE project will have no significant impact. The Finding of No Significant Impact (FONSI) document is available.

How will you keep the public informed?

Fermilab and Sanford Lab will do another round of public outreach before construction starts, and will provide frequent updates and respond to questions and concerns throughout the construction of the project. We also will update this FAQ webpage with the latest information as plans become more definite.

Where can I find out more about the project?

For more information, please read the LBNF/DUNE fact sheet or contact Katie Yurkewicz at the Fermilab Office of Communication (630-840-3351) or Connie Walter at the Sanford Lab Communications Department (605-722-4025).