You can give specific Pokemon TM28 Dig that you get from that town with all those ashes, and I know Nincada learns it naturally if you don't evolve it (I think it learns it Level 45).
Dig is a TM, and you can teach it to most ground types.
diglett, rayquaza, and most ground type Pokemon
RockDark252TreeckoGrass253GrovyleGrass254SceptileGrass255TorchicFire256CombuskenFireFighting257BlazikenFireFighting258MudkipWater259MarshtompWaterGround260SwampertWaterGround261PoochyenaDark262Mightye...
Any Pokemon that are ground type should be able to learn DIG. Hope this helps :)
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