They may just be digging down to cool dirt. Fence off an area that is Fluffy's and let him dig. Get over it. Keep him inside and only take him out supervised. Get him a doggie friend.
Many dogs chew and dig out of boredom.
For Chewing - Don't leave the little buggers inside alone. If you can't watch 'em, crate 'em. Put them outside, or someplace where they can't eat everything you own when you can't supervise. Most out grow this. Labs seem to be the worst and it takes up to two years - they have an extended puppyhood.