Friday, June 11, 2010

Remediating the Gulf Oil Spill Disaster

Among all the things being used to treat the oil spill in the Gulf, I have not seen much about “bioremediation”. That is the use of oil-eating microbes to convert it to something harmless.

This is a technology that I personally know could work. A few years ago, I worked for a local Waco firm in the environmental field. One of their standard responses was bioremediation.

On the internet is a video from 20 years ago, in which the State of Texas used oil-eating microbes to clean up a tanker oil spill in Galveston Bay. This is better than absorbents, because the oil is eliminated in-place, with nothing to pick up for disposal.

I researched bioremediation to see what was available, and how best to use it. There are many firms nationwide offering commercial oil-eating microbes, and these are natural, not genetically-engineered.

I am no expert, but, from that research, I did get a sense for what works and what does not. First and foremost, these microbes work best on surfaces: oil floating on water, or oil still on the surface of soils.

That means bioremediation is ineffective if (1) the oil has soaked down into the soil, or (2) has been dispersed down into the water. That first means you cannot delay treatment for oil coming ashore on a beach or wetland, and the second means that you cannot use “dispersants”, which cause the oil to break up and migrate downward into the water.

Dispersed oil is not remediated or removed, simply relocated to where it is not visible, and to where bioremediation, booms, skimmers, and absorbents are all ineffective. In other words, dispersants act to make the damage to the environment worse, in part by hiding it!

Now, the EPA told BP to use a different dispersant, not to stop using dispersants at all. In effect, the EPA advocates using what it considers to be a “proper” dispersant, which actually makes the problem worse, but in an “acceptable” way!

My research says that the physical state of the microbes, and the additives included with them in the commercial products, do make a significant difference to effectiveness. But those issues are well-understood, so they should not hold back the application of oil-eating microbes to the open-water Gulf, or to any shoreline areas contaminated by oil.

I think I like bioremediation best, because the oil really is “destroyed” in-situ by being converted to microbe waste products, in turn non-toxic to the rest of the ecosystem. It is also self-limiting: once the oil is gone, the microbes die for lack of food.

No mess to pick up afterward, it seems to happens over days-to-months-not-years, and it’s cheap. You can spray it from an airplane or a boat. It makes good common sense.

So, I have two very serious unanswered questions:

(1)Why were we not doing this the first week of this crisis?

(2) How come the EPA did not demand this?

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