With the help of Cecils Engineering book we find that a dozer CAN adequately pack it. However, this assumes that the operator is diligent and doesn't miss any part of it. The guy that did mine didn't have a roller and I didn't know to ask. He also didn't core it and I wish he had. I also didn't know to ask that. I don't think I have any problems but next time I will know better.

I would go check out his work at other places in the area. BTW, don't just accept his references. When you talk to a reference, ask them if they know anyone that he has worked for. You might get a different story from clients that he hasn't told you about.