[Vigilanteman]

Reasonable solution. Beyond the salt mines in Kansas, there are granite vaults in the Rocky Mountain States, superb preservation climates available in the deserts of Nevada or New Mexico at abandoned military installations and a host of other possibilities.

I am not one to pooh-pooh the value of keeping original records, but 99% of your researchers will have their needs met with a certified digital copy. The remaining 1% can travel to Kansas, Nevada or where ever.

[sauropod]

It is always best to use original sources whenever possible.

Sometimes the microfilm copy is really crappy. Having the documents housed in a salt mine is entirely unsatisfactory, in my opinion.