If a dog is a digger, you are not going to stop it. Boredom, needing exercise, etc. may be a part of the problem but I don't care how much exercise they get or how much you give them things to do, they are still going to dig. The only thing you can do is confine him to an area where he is allowed to dig or, as others said put him in a run with a floor he can't dig through or keep him in the house. You can't have a nice lawn and keep a dog on it at the same time. BTW, I wouldn't use the e-collar for this. All of this is JMO and experience.