One of the nuclear power plants experiences a crack in the protection of the core when the cooling system malfunctions. The thought is that the cooling system was tampered with. Healthcare facilities in the area are inundated with victims residing in the area around the power plant. What category of disaster would this be?

This the category of this disaster is a  radiologic disaster

Explanation:

Now in order to gain a good understanding of the solution above let explain the concept

Radiologic Disaster:

   This can be defined as a type of disaster that introduces the presence of a radioactive element(which produces radiation ) where it occurs it is different from a nuclear disaster as a nuclear disaster require a nuclear explosion to produce radiation.

this is poiselle's equation from fluid mechanic in physics. mech eng

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia