Seforim that were ruined in the rain, may they be double wrapped and disposed of by a goy?
It is not easy to deliver them to geniza.
Perhaps there is leniency since they were already damaged?
Seforim that got ruined and are no longer useable is exactly where the halachos of geniza were said. Even after they are no longer useable we still have to treat them with respect. If the seforim are still useable, there may be other issues to just throw them out (but that is not our subject now) .
Rambam Yisodei Hatorah 6-8, Mishna Berura 154-13, Ginzei Hakodesh 8- 1, 2, also see pg. 281.