One other suggestion that I forgot to mention and that I would add is this. I had thought of putting in some text information on a subject within the theme of the cache. That along with some historical photos about the site where I have been considering planting a cache. For that information I thought that it might be good to laminate that material and roll it up into the capsule. That way if dampness does get in the materials should hold up for a while. Again though nothing can replace or eliminate a need to check on your cache from time to time and keep it well maintained. You may find someone near by to check on it if they are more remote from you. Pay attention to Geocache from time to time as some people do post observations about the condition of the caches that they find. That could be a good way to find out if you need to road trip to your cache and check on it. I have thought of all this because a couple of my caches would be planted about 75 to 90 miles away.