Storing these Arraylists

I want to store these arraylists so they won't be emptied on disable or on reload. How do I do that?

Code:

private ArrayList<String> ArenaNameStorage = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage = new ArrayList<Material>();
   
    private ArrayList<String> ArenaNameStorage2 = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage2 = new ArrayList<Material>();
   
    private ArrayList<String> ArenaNameStorage3 = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage3 = new ArrayList<Material>();
   
    private ArrayList<String> ArenaNameStorage4 = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage4 = new ArrayList<Material>();
   
    private ArrayList<String> ArenaNameStorage5 = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage5 = new ArrayList<Material>();
   
    private ArrayList<String> ArenaNameStorage6 = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage6 = new ArrayList<Material>();
   
    private ArrayList<String> ArenaNameStorage7 = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage7 = new ArrayList<Material>();
   
    private ArrayList<String> ArenaNameStorage8 = new ArrayList<String>();
    private ArrayList<Material> ArenaBlockStorage8 = new ArrayList<Material>();

 

@timtower how would I do it than?

 

@KarlBrewer http://wiki.bukkit.org/Configuration_API_Reference