CERN and concrete in the same discussion thought someone smarter might see something here.
What is CERN?
CERN based in Switzerland is the world’s largest particle accelerator used to collide charged protons which are then rerouted to the Large Hadron Collider where a study is made of the collision of particles similar to those of the big bang.
What is a ‘beam dump’?
A small example is when a powerful laser needs to be shielded to prevent damage or harm if it can not be turned off. Concrete is used to absorb laser energy safely as an alternative way of switching it off.
CERN has a powerful feed of energy that is charged by spinning in a circular tunnel. If the feed is not travelling fast enough for research or have not enough particles in the beam left after the collision, it will no longer be used and will need to be dispersed away from equipment and people. The energy is sent underground with a tunnel protecting from radioactive shielding which then hits a high mass of concrete deep into the earth; the earth’s soil absorbs the rest of the heat.