Digging back over the ditch is something that is done occasionally but may not be a good idea for a "Newbie". The most likely problem is not backing over the ditch but progressing forward as you get the ditch re-dug. Unless you have pretty good control you may end up with a front wheel in the ditch. This is far more trouble for a novice operator than dropping in a rear wheel. Normally results in screwing up the whole ditch. Save yourself some time and just backfill the ditch and re-dig. If it's only 30 feet it won't take but a few minutes. Backing over a ditch can severely weaken the walls of the ditch. DON"T DO IT if it's going to be more than 4 feet deep and you have to get in the ditch after it's dug.
Safety is always a serious topic of conversation on this site. Trench cave-ins are probably responsible for as many deaths and injuries as as tractor rollovers but I have never seen them mentioned here. A trench 5 feet deep can cave in and crush you to death! You usually won't suffocate. The weight of the dirt can crush you instantly. It happens so quickly there's no chance to react. OSHA requirements for trench safety are quite extensive and should be! Trenches 5 ft and deeper may be required to be shored, boxed, jacked, or sides sloped at 45 degree angle. There are Regs for placement of the spoil pile, limits for how close a machine can get to the ditch... There are similar requirements for unsupported, excavated banks like basement and retaining wall excavations. I personally know of 5 men killed in trench cave-ins. One was 35 years old, 6 ft 5 inches tall, crushed in a 5 1/2 ft ditch. Three at one time in a 10 ft deep 6ft x 6ft manhole excavation. The oldest of the three was 22.
