Can adults and juniors share a practice space?

As long as there is clearly understood separation between the area where the juniors are practicing and the area where the adults are practicing, your liability and accident insurances are in effect. For example, juniors are practicing on turn 4 and adults are practicing on turn 2 and all the participants understand this. If there is no clear separation, accident insurance is still in effect but liability insurance is not. This is also true of roller discos, parades, and non-contact skating.