Speak to Skagway @ 19 67 -178
Evaporate the water that filled the mines.
You'll need the move Overheat
Save the Miners in the mine.
Find Brisbee @ 18 48 -200
Battle a level 32 Graveler on the path
Find Jermone @ -48 47 -189
Battle a level 32 Onix on the path
Find Ruby @ -51 51 -238
Battle a level 32 Rhydon on the path
Battle a level 32 Lairon on the path
Find Custer @ -56 46 -302
Battle a level 23 Relicanth on the path
Find Coal @ -94 49 -305
After the cutscene with Coal, you've completed the quest and will receive these rewards: