After all is assured to be secure, normal NTS operations resume. The event site is roped off, outlining an exclusion zone where there is danger of potential cratering. After the temperature of the cavity has cooled, a post-shot hole is usually drilled into the point of the explosion in order to retrieve samples of the debris. These samples are highly radioactive, but provide important information on the test. After drilling and sampling operations are complete, the drill rig and tools are decontaminated.
Residual radiation is cleaned up at the site, and the hole is plugged back to the surface.