Hello hemiguy; I don't know exactly what kind of fill dirt you plan on using, but I would use just plain red clay. If the dump trucks can back up to the hole ,all the better. If not you've got a frontend loader. Fill the hole in almost even with the ground with red clay. Pack it with your tractor tires good. Then overfill the hole with good top soil at least a foot higher than ground level, plant something of her choice and let mother nature do the rest. Six months later the settling will be over and the area can be sodded or whatever. Just my 2 cents worth. Good luck with however you decide to go. All things work better with "GOD" as the co-pilot.