Tony:

Your state probably has an engineering association.  My husband is an engineer
and is a member of GSPE, the Georgia Society for Professional Engineers.
Since you have limited time,  I'd suggest organizing a group of engineers as
volunteers to sort and catalogue the books before you deaccession any of them.

Re:  what to save and how to tell what is valuable.   David Jenkins' wife at
Berkeley does engineering research.  She is a librarian.  (My husband was
David's student years ago).   I would try to find Mrs. Jenkins via the
Environmental Engineering Department at Berkeley.   She might be able to tell
you what to be on the look out for re: rare engineering books.

Once you decide which books you want to get rid of, you might be able to
surplus some of them to Latin America.   Our state association of water and
water pollution engineers have volunteer engineering projects they run in
Latin America.   Libaries are not well stocked and they always want books.
You can try the national associations of engineering on the web for specialty
areas like water pollution, civl
engineering, etc., and maybe you can send the books with volunteer engineers
when they go to do their projects abroad.

Good luck and happy book sorting.

pamela sezgin
georgia mountains history museum at brenau university
gainesvillle, ga