Secondly, I wouldn't object to there also being criminal penalties for corporate leaders in such cases if it can be proven that their actions or inactions directly caused the damage. However, in our society, money is usually the only penalty awarded in tort cases - hit them with big enough damages and eventually they will change if it's in their power to do so.
Finally, pipelines are by far the safest mode of transporting crude to refineries and refined oil to market - bar none. In 2012, there were a total of 54,000 barrels of oil released into the environment through pipeline leaks which, while it sounds like a lot, is a miniscule proportion of the amount of oil flowing throught pipelines in North America every day. But the media pumps it up because of the politics of the Keystone pipeline in the news now. I'm wondering how many people, nationally in the US, heard about the 15,000 barrels of oil spilled in Minnesota a couple of months ago due to a train derailment - not too many, I'll bet - it doesn't fit the media's agenda.