Factual error: The Rayovac batteries in Chuck's tape recorder use the wrong design for the time period this episode is set.
Revealing mistake: When Kim is leaving Gatwood Oil and realises her car is stuck in the dirt, the car is still in park. No wonder it's not going anywhere.
Answer: The bulldozer could be disassembled, the individual pieces carried down, and then reassembled once underground.
BaconIsMyBFF