Modern smokeless powder has a shelf life of about 1/2 of forever if properly stored. If it has been in "living space" ... It should be about as good as it was when it was made... thus:
1). If you want to use it... No two batches of powder are exactly the same. Work up loads with GREATEST CAUTION! Greatest!!! I have fired ammo from just after WW I. Shot fine. Needless to say, corrosive. Pain to clean, but shot fine.
2). Go find some collectors. The big gun nuts in your area. No telling what it is worth to them either for use or display. Hodgdon got his start post WW II selling surplus at $0.50 a lb. retail. 8lbs. would be $4.00... Retail... And '06 brass was free if you would go pick it up... some places. (Uncle Sam's boys shot it and left the brass lay...). Compare today's prices. Might be the best investment you own. Luck. Happy Trails.