Canadian Natural Resource Limited was charged last Friday for hydrogen sulphide (H2S) releases at its Horizon mine and upgrader. The company has paid $35,000 in fines for sulphur dioxide (SO2) emissions since December 2010. The charges it currently faces are for the release of H2S on May 28, 2010, and then not reporting that release between May 28 and June 3, 2010. I assume they did report it after that time since I don't see how the province would know to charge them otherwise.
H2S is a much more dangerous gas than SO2. I suspect they'll face a much stiffer penalty for releasing it.