I disagree with the advise that you will face a massive fine if you haul the dirt on a public road. I have been on the WCA environmental commitee and have first hand knowledge with my state environmental agency and the state of California agency. Pit dirt is classified as street sweepings by the EPA, and most state environmental agencies. First have your pit dirt tested. Then after that as long as you are keeping the same type of business you do not have to retest t each time. The pit dirt should be dried using the EPA guidelines with a paint filter to reveal how much moisture is in it. I always let it dry on my own land. I have a pit pump and a tractor with custom
front loader bucket to clean the pits.
3 times I have had "concerned citizens" call the state environmental agency and tell them I was dumping all kinds of hazardous waste. The agency has come over 3 times and seen how I handle the mud and they have given me their blessing that I am doing everything right. Once the pit dirt is dry you can do what ever you want with it. Even California has tested and determined this. I use a dump trailer with a gvw under 10,000 lbs. so I am not subject to CDLs etc.