The tablets are the preferred mode of storage, but heavy paper bags of powder are easily stored in wood boxes or drawers.
It can also be obtained in PVC canisters.
My recollection was a problem from buildup of chlorine gas in humid conditions, and a huge corrosion problem with anything metal anywhere near where the solid stuff was kept.
Totally solved going to sealed drums of bleach. Of course, the liquid takes up much more space, and is very heavy in comparison.