its not "normal" but it is "safe" the 6870 gpu's are designed to cope up to 105c
But it does sound like your in need of better case ventilation as my 6870x2 + 6870 cfx never go over 82 and the duel gpu 6870's are notoriously hot.
just be sure to get some extra case fans
A side panel fan is quite good for getting extra air under your card... just dont want too high of a cmf otherwise it will screw with your whole cases airflow pattern.
Another thing that can help quite allot is taking off your cooler from your card, and replacing the thermal paste.. It did wonders for my sapphire 6870 cut my idle temp from 62 to 48 and load from 87 to 79(in crossfire scenario with little airflow gap under card) and 14c is nothing to turn your nose up at