There are pollution laws, but unfortunately companies receive only relatively minimal fines. So depending on the substance and quantity 'accidentally' leaked, i

There are pollution laws, but unfortunately companies receive only relatively minimal fines. So depending on the substance and quantity 'accidentally' leaked, it may actually be a cost saving for the company. And granted, in sure a lot of pollution actually is accidental, but even there the reasons are likely due to the company cutting costs which led to an accident. For instance, let's say there's a bake that had a high likelihood of soon failing. When you take into consideration the cost of a replacement valve, service to replace it, and down time of processes that depend on this valve and compare it to the amount you'd get fined for a spill if the valve fails, many companies will take the risk of the valve failing because the fines just aren't high enough. The other thing is that there's almost never any jail time for those that were involved in the decision making process to take that risk. Case in point, BP oil spill, nobody has served jail time even though there were numerous reports that people were aware of the risks of continuing to operate without replacing the valve that failed.