I'm guessing that the distance is about 1000' long, 10' wide and 3' high that you are wanting to add. If that's correct, then that's 30,000 cu ft or 1111 cu yd of dirt. Your bucket is about 8 -9 cu ft. so you have 3000 buckets full to do.
Don't forget to compact the soil every 8-12".
I'd laugh, but I have a similar job to do. I'm looking for a small 1 ton with a dump box... It sure does look like a lot of work in that picture! Good luck.
jb