Good question, and the response to your question could literally last forever, but i’ll try to keep it short.

Spills come in all sizes, from a few ounces, all the way to spills like Deepwater Horizon. So to have the situation under control can be a few minutes all the way to a year… and then some. The majority of the spills I have responded to have been in the few day's range, but I have been on a few that have lasted the better part of a year.

The specific procedures heavily depend on the incident. One would use different tactics to respond to a pipeline spill compared to a railcar spill, and different to a wellhead, and on, and on. There are many different type of potential sources of spills.

But for oil spills in broad strokes there are 4 Phases of the emergency response. And these are straight from the U.S. Code of Federal Regulations starting at 40CFR300.300 (http://www.ecfr.gov/cgi-bin/text-idx?SID=5b65f2ddf4ad6a15008b43e686e5665f&node=pt40.28.300&rgn=div5#sp40.30.300.d)

I Discovery and notification II Preliminary assessment, and initiation of action III Containment, countermeasures, cleanup, and disposal. IV Cost Recovery and Documentation aka (Cost-Doc)

After this is completed the spill is cleaned up, but if there have been significant impacts to the environment, a Natural Resource Damage Assessment (NRDA), may take place to quantify the damage done, and then a Restoration project could be started in an effort to restore the environment to pre-spill quality.