I'm helping a friend fix his trashed property.
The place has been neglected for a long time and thus has suffered extensive water damage. Power to the sump pump has been off for many years, and the basement stayed a swimming pool. The exterior grading is also poor, and the perimeter lawn grows at the level of the rim-joist.
Some major earth moving is next on the to-do list, but for now it's one step at a time.
The space pictured is under a master bedroom addition. There is no cross-ventilation and it is wet now.
Needless to say, yes...the hardwood floor above is very bouncy(2x6's notched).
He wants to just put some plastic tarp on the ground and fill the whole cavity with blown-in cellulose. At this point, I can't think of a better solution.
Structural issues, mold issues, water damage, and drainage concerns; what will a blue tarp and cellulose solve other than you just won't be able to see the numerous problems you buried in wet, moldy, insulation? You and he have some serious research and work ahead of you. You can, and I strongly advise you to, search this forum for numerous ways to insulate or waterproof a foundation and/or crawl. What you are proposing will solve neither. Here is a website I took a lot from in healing my own crawl space: http://www.buildingscience.com/docum...n-crawlspaces/
You'll also find a lot of info here on fixing the glaring structural issues with the "bouncy bedroom" also. (which will be near impossible if you blow in a foot of cellulose where you'll need to be working)