Underground nuclear testing "Effects" Our BOMB could have

[2cansam]

The effects of an underground nuclear test may vary according to factors including the depth and yield of the explosion, as well as the nature of the surrounding rock. If the test is conducted at sufficient depth, the test is said to be contained, with no venting of gases or other contaminants to the environment. In contrast, if the device is buried at insufficient depth ("underburied"), then rock may be expelled by the explosion, forming a crater surrounded by ejecta, and releasing high-pressure gases to the atmosphere (the resulting crater is usually conical in profile, circular, and may range between tens to hundreds of meters in diameter and depth
Other surface features may include disturbed ground, pressure ridges, faults, water movement (including changes to the water table level), rock falls, and ground slump.

^So maybe that's why babies die after only a few trimesters "contaminated water from the blast being in a tunnel next to a water source."

http://en.wikipedia.org/wiki/Underground_nuclear_testing#Effects

[Timmy]

Remember this was only a trigger device..a small explosion which makes the real large bomb to go prompt critical - nuclear explosion. The whole bomb is small 10-20 kilotons.

[Paradise Lost]

Remember this was only a trigger device..a small explosion which makes the real large bomb to go prompt critical - nuclear explosion. The whole bomb is small 10-20 kilotons.

10-20 kt is still a HUGE explosion. Hiroshima was 10-15, Nagasaki was 20-25.

[Timmy]

That would be the case if the trigger set off Jughead. It is by the way a small nuclear device. The current bombs are in the megaton range... 1000 times more potent.