On the frozen surface of Dongting Lake Region, a group of engineers were drilling into the ice layer and, once they reached a certain depth, burying pre-prepared explosives.
They didn't intend to blast open the ice layer but planned to use the shockwaves generated by the explosion to conduct geological surveys underground and determine the position and trajectory of the subterranean caverns.
This was in preparation for the excavation-based attack plan devised by Chen Xin.
Although Chen Xin had prepared for how to defend against the alien life forms in the underground caverns that might damage the shield tunneling machine and tunnel when designing this plan, both the military and Chen Xin himself hoped to find a tunneling route that could avoid the existing underground caverns.
This would certainly save a lot of trouble, as being able to dig directly downwards to the alien life forms' nest and then attack would be very efficient and easy.
