Yuck - Salt!

[Freedom]

If getting the boots on is too difficult in the rush, what about a quite epsom salt in water bath for his feet when he returns in. That will help cleanse them. Shouldn't take much, a small dish basin works fine. Warm water, epsom salts, let him walk through that and towel dry.

I hope others have some ideas for you!

[Louie and me]

That's a good idea - I have just been wiping them with a wet cloth and they drying them.