Your Bonsai is in big trouble and to save it I sugest that you plce it in
a larger pot with sand around the original root and soil configuration.
This should get air to the roots. The moisture and air should stimulate
the root tips to begin to grow again. Keep the sand moist and place the
pot in a shady location. Mist the leaves and branches to reduce
transpiration. Do not fertilize until new growth starts and only with a
quarter strength solution of 20-20-20. Junipers are outdoor bonsai and
should be brought indoors only for a special display period.