I'm thinking explosives should do the trick.
A few years ago I was in charge of company records for a large engineering firm. Our product was Environmental Impact Reports for the U.S. Navy. We had a garage size storage room in the downstairs parking garage. It was below ground level. You see where this is going? A water line broke on the 13th floor one weekend, and two days worth of water traveled down the elevator shaft, into the garage, down the typical garage incline to the floors lowest point - our storage room.
YES - have a professional clean it up. They do use a disenfectant. They do a very good job and we had very minimal losses from thousands (millions?)of pages of documents.
YES - have a professional clean it up. They do use a disenfectant. They do a very good job and we had very minimal losses from thousands (millions?)of pages of documents.