Slashdot Mirror

There's this widespread mistaken belief that radiation is not normal, and is only created by nuclear weapons and nuclear reactors. Radiation is completely normal and is everywhere around you.

The highest radiation dose most people receive in a year actually comes from their own bodies. There's a naturally occurring radioactive isotope of potassium, and our nervous system needs potassium to function. Likewise, foods high in potassium can give you an elevated radiation dose. The radiation sensors at our border checkpoints designed to detect terrorists trying to smuggle in a dirty bomb are forever being triggered by cat litter, tiles, and foods high in potassium like bananas, nuts, etc..

After that comes rocks - mainly granite, but also things like beach sand. They have trace amounts of natural uranium which is radioactive. Having granite countertops in your kitchen substantially increases your annual radiation dose. The radon which can build up in your basement if you live in the mountains comes from rocks. Radon is one of the byproducts of uranium's natural decay chain.

After that is cosmic rays from space. Living at higher altitudes increases your exposure to this radiation source, since there's less atmosphere above you to absorb it. A transcontinental flight exposes you to about as much additional radiation as a medical x-ray. All the people who fled Japan after Fukushima by flying home unwittingly subjected themselves to more radiation during the flight than they would have received from Fukushima if they had just stayed in Japan.

Anyhow, uranium is water soluble. As a result, seawater has a much higher concentration of natural radionuclides than you normally encounter on land. So if you're that paranoid about radiation, you shouldn't swim in the ocean (you shouldn't even go to the beach, where the sand and sun will irradiate you). The increase in radioactivity from pre- to post-Fukushima is tiny compared to natural levels. The reason we know it's coming from Fukushima is not because the water has suddenly become radioactive. It's because the radioactivity is coming from certain isotopes which have short half-lives so have long since disappeared as a natural radiation source. Fukushima was the only recent event which created a bunch of those short-lived isotopes, so we know that if we detect radiation from those isotopes, that they must have come from Fukushima.

Here are a couple of links that I found that are interesting.

General Info and Benefits - http://www.waterencyclopedia.c...
Why they are Harmful - http://www.waterencyclopedia.c...

Here are a couple of links that I found that are interesting.

General Info and Benefits - http://www.waterencyclopedia.c...
Why they are Harmful - http://www.waterencyclopedia.c...

All the numbers make people's eyes spin and they will not understand any of it.

It may be easier to say, that if Uranium cost $250/lb, it would become profitable to extract it from the ocean water. That's how much uranium swims naturally around in the oceans. And if you combined all the radioactive minerals dissolved into the seas, you'd have more radioactive material than released by 1 million Chernobyls.

http://www.waterencyclopedia.com/Po-Re/Radionuclides-in-the-Ocean.html

So, any radiation released from any nuclear accident is a purely local, maybe regional issue.

PS. I'm not advocating dumping of wastes into the oceans. I support nuclear energy precisely because it is the only power generation source that does not just dump its waste.

I don't get how intelligent people can be so dumb.

Yes there is ocean acidification.

And for that to realize you don't need any scientific numbers about the ocean. You only need to use your useless brain.

Ocean = Water
Atmosphere = N2, O2, CO2 etc.

Last time I checked the ocean and the air was in direct contact. In other words there is no magic shield preventing O2, N2 and CO2 exchange between the air and the ocean.

If you really believe that increasing the CO2 concentratoin in the air does not result in an increased CO2 concentration in the ocean, you must be stupid as hell.

Ah well, and for your interest: http://www.waterencyclopedia.com/Bi-Ca/Carbon-Dioxide-in-the-Ocean-and-Atmosphere.html or perhaps simply google: http://www.google.de/search?q=CO2+increase+in+ocean

Oh I was insulting and arrogant again, wtf ... go off my lawn.

It's dumb..

True, most only really think of oil as being the next big thing to cause mass hysteria, but few realize that potable water is a dwindling resource in certain regions. Even the giant Ogallala aquifer in the central United States is showing increased rate of depletion (not to mention pollution).

There are a few books on the subject.

Oceans cover 70 percent of Earth's surface. We have barely begun to tap the resources that lie on the bottom of the sea. The ocean beds are rich in countless minerals. About 20% is thought to be covered by manganese nodules, which can contain as much as 2.5% copper, 2% nickel, 0.2% cobalt and 35% manganese, as well as titanium, aluminium, potassium, molybdenum, lead, strontium and other substances. The greatest unexploited mineral resources on earth are on the deep-sea floor, including manganese nodules; cobalt-rich manganese crusts that contain nickel, copper, cobalt, and manganese; and hydrothermal deposits that contain copper, lead, zinc, gold and silver. Deep-sea mineral resources are found in specific areas. Manganese nodules are half-buried in comparatively flat deep-sea sediment at a depth of 4,000-6,000 meters. Cobalt-rich manganese crusts cover the slope or top of seamounts like asphalt at a depth of 800-2,400 meters.

I believe that in the future we will routinely mine the ocean and it will become a huge industry. We will have great machines that will work around the clock mining the sea floor.

It goes both ways. There are some good farmers out there, and some of the worst pollution comes out of factory farms. But, though I am not a "degreed biologist living amongst the rustics" I am married to a nationally recognized environmental journalist, and I do have more than a little environmental background as well. Farms use a hell of a lot of fertilizer and a hell of a lot of pesticides, and though both vary depending on the crop, neither one is remotely environmentally friendly, and there are always issues with estuaries and water table runoff. Don't believe me? Believe the American Chemical Society

And to blame fricking golf courses for the majority of pesticide pollution in this country is laughable. Fertilizer? Maybe. They're up there. But they cover such a small amount of space compared to the amount of land in this country that is under cultivation. Now, home users, with their nice green lawns, again, possible point, but that's not cities, that's the goddamn suburbs.

I've lived quite a lot of my life around farms and farmers...Mostly eastern, so Tobacco, Cattle, Chickens, Pigs, Tomatoes, Tree crops, and Cotton, so I'm not quite as ignorant as you seem to think. And, since I'm sure you have better sources for statistics than I do, I'd really like to see some numbers on "latest techniques" especially where water use and soil conservation come into play. My numbers basically say that water sources are drying up and becoming contaminated and that soil loss (in indiana in 1997) hit a 50 year low...with a mere 2.9 tons per acre.

Frankly, and I've seen it pretty often, I think you're suffering from some serious arrogance. You're completely right, and I'm completely wrong. My points have no merit (drawing down the aquifers? Hello? This is a no brainer.), and yours do, but not because you backed up your assertions (you didn't) and not because you didn't lay out some outlandish assertions (you did), but because you're all educated, and I'm just a dummy from Georgia who should just back off what'n all I don understand...Speaking of "redneck" stereotypes.

So get off it and prove me wrong, or shut the hell up.

Is that the sound of a knee jerking or have you actually bothered to check?

I have actually bothered to check. Extraction of industrial quantities of almost any mineral (other than salt and magnesium) is imaginary technology. Imaginary technology--like commercially-viable fusion power--is good, and should continue to command our imaginations, but it should not be the basis for public policy.

The claim that "there is enough economically extractable uranium to last billions of years" depends on a series of unjustified and quite possibly false claims. One of those claims is that it is possible to extract large quantities of uranium from sea water using less energy than the uranium contains.

So let's do the math. To make thing easy, I will give Cohen the full benefit of the doubt and use his own figures whenever possible. The article you link claims that a) there are 3.3 ppb U in sea water; b) 6500 tonnes of U per year would provide 25 times the current (1983) world electricity usage. A little quality time with Google shows world electricity usage in 1983 to be just below 8E12 kWhr, so a tiny amount of math tells us that based on the author's own figures we would have an energy budget of 360 kJ/kg of seawater processed, assuming we use 100% of the energy available in the uranium in its own extraction.

360 kJ is enough energy to keep a 100 W lightbulb alive for an hour. It needs to be enough to pump, process and discharge a litre of water to extract the 3.3 picograms of uranium it contains with nearly 100% efficiency to make this work. Maybe that's possible, maybe it isn't. It isn't a vast amount of energy--think about running a 1 kW generator for 6 minutes. Would that really supply enough energy to pump the water, run the chemical reactions, and concentrate the extractant by a factor of a billion or so?

It isn't obvious this is impossible, but it is a long, long way from obvious that it is possible, too. And without the factor of 1000 that you get from assumming breeder technology the you only have enough energy to keep that lightbulb on for 3.6 seconds, which makes it pretty obviously a non-starter.

As I pointed out, breeder technology has issues with moving thousands of kilos of plutonium around every year, resulting in inevitable uncertainties that will make it possible to lose enough plutonium each year to build multiple bombs, any one of which could ruin your whole day.

None of this proves that nuclear is a definite non-starter, but I wish nuclear advocates would acknowledge the problems, much as I wish nuclear opponents would acknowledge the benefits.