When Eric catches up with the two men who stole the drilling rig, the bit on the rig is 12 to 18 inches in diameter. Later when Eric goes to the hole, it is shown to be at least four feet in diameter, made with a single bit.
The wasps on the mammoth inside the cold storage room would have escaped through cracks in the building and around the doors unless the building was hermetically sealed. This building was very old and would have had many ways for the wasps to escape.