Gentle readers - I just wanted to step in to clarify one point.
When Becky dropped her token it was at the moment of her death. The canon sounded signaling the death of a tribute before the mine went off so she was already dead when the mine was triggered.
Becky died of natural causes even though it might appear that it was the detonation of the mine that killed her.
Please keep in mind that this is our little secret. Don't say a word to Clark.