This response is forwarded from Mike Sloat, Printing Sector
Specialist for Wis. Dept. of Natural Resources.
Talked to a solid/hazardous waste inspector in the region. His answer
is that as long as the material can be used for it's intended purpose,
it would not be considered a waste. But, he also stressed it would be
a case by case decision. This answer will only apply to Wisconsin.
It would seem rather strange that a substance would be considered a
waste after one year on the shelf. Many products have a shelf life
longer than a year.