by CKR
ABC News tonight featured an interview with an EPA employee who said that "Love Canal is microscopic in comparison to New Orleans." I can't find a link yet.
The interview was set against a seriously black, Charlie Rose-style background. Footage was shown of yucky looking stuff oozing out of the ground at Love Canal, and a father who lost two daughters to birth defects there was predictably interviewed.
This is the kind of science coverage I just hate. It adds to people's fear without adding to their understanding.
The EPA employee's contention, as I understand it, is that nobody should be allowed back into New Orleans "without a complete assessment." This is also the kind of thing that makes people believe that scientists are impractical people without experience of the real world. I don't know to what extent the report accurately reflected the man's concerns. The interview was clearly edited, most likely for the most sensational bits.
Let me try to lay out the facts and decisions as I see them. A lot of the necessary facts are not generally available, which is why I haven't said much in the last week or so.
The ABC report said that 18 samples of the sludge that remains after the water goes down have been analyzed. They didn't say for what, or what was found. Earlier reports mentioned elevated levels of cadmium and lead. There is undoubtedly oil, which could be seen as a rainbow-like sheen on the water in many photos of the flood. There are probably other components, like insecticides and whatever may have been in that Agricultural Street Landfill.
The overwhelming findings of the sample analysis seem to be fecal bacteria. They will remain in the sludge, although some will die as the sludge dries out and as they are exposed to sunlight. Others will go into inactive forms, and if the dry sludge forms dust, they may be breathed in.
The overwhelming danger to the people returning to New Orleans is from the bacteria, which can cause disease right now. That danger is most immediate in the water coming from the taps, which is not safe, but I have no doubt that some will drink it.
There are two big differences between New Orleans and Love Canal: time and concentration. At Love Canal, houses were built on the landfill, breaking the cover and opening up the toxics below. Those toxics were in more-or-less pure form. So people were living in houses that became permeated with large quantities of nasties.
In New Orleans, the concentrations of the nasties in the sludge are much less. Just as a spoonful of sugar by itself is much sweeter than a teaspoon of sugar in a cup of tea, that viscous goo at Love Canal was much more dangerous than the stuff floating in the water or remaining in the sludge in New Orleans.
It is possible that the EPA interviewee on ABC was trying to say that the situation in New Orleans covers a much wider area than "microscopic" Love Canal. It's possible he clarified his remark but ABC shortened it down. While the materials may be more widely distributed, the concentrations will be much smaller and therefore less hazardous.
As I understand the re-entry into New Orleans, people are being allowed to go back to see their property. This is really important--I suspect that nobody who hasn't been evacuated can fully understand how desperately those people need to see what has happened. It's important both financially, so they can begin negotiating with their insurance companies or making plans for rebuilding, and psychologically. It's much, much better to know the worst than to fantasize about it.
They are not being allowed to go back to stay: there is no potable water, and the houses that have been flooded are not liveable for other reasons. Probably only a small minority would want to stay. Being around sludge that contains hazardous chemicals for short times will be about as dangerous as, say, smoking a cigarette or two. While it's desirable to keep people from any sort of danger, the danger from the hazardous chemicals and even the bacteria has to be balanced against being able to deal with the results financially and psychologically. I would come down on the side of letting them back temporarily if appropriate safety provisions are made, as Thad Allen has laid out on the Sunday talk shows.
For the longer term, there is going to be a lot of junk in the soil, even if the sludge is removed. Levels of nasties are likely to be above those allowed for land that people live on. Those levels are likely to be different in different places--maybe worse around gas stations and that landfill, but water can move things in strange ways. The more complete assessment that the EPA interviewee referred to will be appropriate to determine how to reconstruct the city.
But there is no such thing as a complete assessment. Sample analysis is expensive. If you take a sample from the front yard of one house on a block, the other homeowners will wonder about their yards. If you take a sample from the center of each front yard, you can still wonder about the corners. Statistical methods can take some of the uncertainty out of this, but they don't fit easily with most people's intuition.
Still, it would be nice if some official would have stated the tradeoff: a bit of danger to those going back into the city in return for finding out about their property. That would, of course, have implied that the official had some responsibility for that decision, and apparently this is not being done these days.
Look for lots more upset and fighting over these issues.