It's useless if it gets wet before you use it It's fine if it's wet as long as it can still be spread by the spreader. In fact, there has to be some moisture i

It's useless if it gets wet before you use it It's fine if it's wet as long as it can still be spread by the spreader. In fact, there has to be some moisture in order for the salt to lower the freezing point. It can't mix easily with frozen ice that has no free moisture. "Pre Wetting" salt is actually a tactic used for snow/ice mitigation for this exact reason.