When Luci and The Man are digging up the barrel, they are clearly seen to be using two shovels - one each. However when they go to leave, Luci grabs one shovel, and the other is nowhere to be seen as the camera pans out. Although that is because both shovels have been put in her duffel bag and can be seen as she approaches the helicopter.
When the nurse describes Billy to Helen she says that he had " a cowboy hat and everything." But Billy wasn't wearing his cowboy hat when he talked to the nurse.
A guy is in an oil drum buried underground and using a cigarette lighter, this would burn up any oxygen he might have left and he would suffocate. But luckily there is clearly a black air tube ventilating the drum. This is how the scorpion gets in.
Helen says her fiance wants to go to Florida to go to Disneyland for their honeymoon. Disneyland is in California.
During the dust storm Luci and Elliot the Man leave the cab of the truck and climb into the truck bed for "shelter".