Forget Covid, Fukushima is what you should be really worried about

[Lake-Effect]

Originally Posted by Dockhead

No, you don't.

The mass of Earth is about 5.9722 x 10^21 tonnes. You can dilute pretty much anything in that; certainly

Maybe, but you'd have to stir really, really hard. And wait a millenium or two, with some pollutants, before their harm or toxicity abates (...assuming we have the sense to stop adding to the problems). And/or the affected ecologies evolve, or disappear.

...and by definition anything which was extracted from the Earth in the first place.

That's some hubris. We've made products/byproducts/emissions with toxicity and longevity that do not exist in nature. And in significant, consequential, accumulating quantities. But sure, given enough time... I suppose they'll break down eventually. So sorry for those of you affected while we wait. Heck, the Great Reset (solar death) will happen in 4 billion years or so. That'll fix it too.

On-topic: physics and math confirm that dilution is indeed the most reasonable approach to deal with the radioactive water stored at Fukushima.

[Ken Pole]

Air travel or spending any time in a boat involves much more radiation!

[sailorboy1]

Originally Posted by Jim Cate

There are better things to worry about!

Jim

Like gaint man eating ants or spiders. I have seen the movie documentries.

[Mrkva]

It's interesting how there are 30 pages discussing what is effectively 15 !grams! of tritium.
To put things into perspective... A medium sized tritium keychain (I love those on flashlights, boat keys, and other important things) contains around 15GBq of 3H. Those are completely safe for end users, with no risks even if broken.
Planned discharge from Fukushima is 22TBq/year, equivalent of ~1500 of those keychains. That's 4 per day.


Or another way to look at at - if we create an artificial cylinder with 1km diameter and 50m deep, and keep a yearly discharge there, we'll reach a concentration of 550Bq/l. EPA limit for drinking water is 740Bq/l.


This is a non issue.

[senormechanico]

I remember luminous dials on wristwatches that glowed without ever needing exposure to light. Tritium.

[RaymondR]

If the tritium has a half life of 12 years and heavily diluted is a low source of radiation it's a lot less of a problem than plastics in the sea.

[GordMay]

Originally Posted by donradcliffe

Your stance on global warming is that if an overwhelming majority of scientists agree on something we should believe them. In this case an overwhelming majority of scientists believe that the release of the Fukushima tritium will not cause a problem...

I apologize.
Apparently, I’ve been VERY unclear.
I have not objected to the discharge of [±1.25 million tonnes] ALPS-treated tritiated water, from the Fukushima Daiichi nuclear power plant, over the next 30 years.

In fact, I deliberately emphasized [#393] that the ‘... release will have a “negligible radiological impact on people and the environment.” ...’ .

My objection [#396] was to the universal, and unreserved statement, that “The solution to pollution is dilution.”; saying that: “The phrase is, in many cases, incorrectly [over] used, and abused ...”

Were I to substitute my own [probably ‘clear, simple, and wrong’], universal, and unreserved statement, I might say: “Prevention is the solution to pollution.”

The tritiated water, to be discharged from Fukashima is diluted, to reduce the tritium concentration, to less than 1,500* becquerels per litre [Bq/L], at it’s spill point, whereupon it will be even further diluted in seawater.
That is about 15% of the limit, recommended in DRINKING water, by the World Health Organization’s guidelines.*

* Some National Tritium Limits for DRINKING Water:
Australia limit = 76,103 Bq/L
Finland limit = 30,000 Bq/L
WHO limit = 10,000 Bq/L
Canada limit = 7,000 Bq/L
US EPA limit = 740 Bq/L*
European Union screening limit = 100 Bq/L [to indicate the possible presence of other artifical radionuclides, automatically triggering an investigation if reached]

* The US EPA's dose-based drinking water standard of 4 mrem per year, is based on a maximum contaminant level of 20,000 picocuries per liter [740 becquerels per litre, where 1 pCi = 0.037 Bq] for tritium. If other similar radioactive materials are also present in the drinking water, the annual dose, from all the materials combined, shall not exceed 4 mrem per year. This standard was expected to be exceeded only in extraordinary circumstances.


Since it is assumed that any exposure to radiation could pose some health risk, it makes sense to keep radiation doses as low as reasonably achievable [ALARA].
ALARA is a radiation safety principle for minimizing doses, and releases, of radioactive material, by using all reasonable methods.
In principle, no dose should be acceptable, if it can be avoided, or is without benefit.
The NRC requires that nuclear plant operators must keep offsite radiation doses from gas and liquid releases, as low as reasonably achievable.
For liquid releases, such as diluted tritium, the ALARA annual offsite dose objective is 3 mrem, to the whole body, and 10 mrem to any organ, of someone living close to the plant boundary.
This ALARA objective is 3 percent of the annual public radiation dose limit, of 100 mrem, and a small fraction of the natural background radiation dose.
The NRC's analysis shows, doses to the general public, from abnormal tritium releases, at nuclear power plants, are well below the strictest protective limits and, therefore, do not pose a measurable risk to public health and safety.

[GordMay]

To be even clearer:

1. My objection to the phrase, is to the heavily “implied”, but unstated meaning:
The “best/only” solution to “all” pollution is “always” dilution.

2. In my layman’s view [& that of most subject experts], the tritium releases, from Fukushima , will be well below the strictest protective limits [under the ALARA principle], and, therefore, will not pose a measurable risk to public health and safety.

[Lake-Effect]

What Gord said.

[Dockhead]

Originally Posted by GordMay

To be even clearer:

1. My objection to the phrase, is to the heavily “implied”, but unstated meaning:
The “best/only” solution to “all” pollution is “always” dilution.

2. In my layman’s view [& that of most subject experts], the tritium releases, from Fukushima , will be well below the strictest protective limits [under the ALARA principle], and, therefore, will not pose a measurable risk to public health and safety.

I agree with you.


A minor quibble: dilution CAN ALSO be prevention in some cases. Most pollution is putting some elements or compounds where they shouldn't be, or in too much concentration.



Dilution is not a solution where the problem is that the substance is in the wrong place -- e.g. carbon in the atmosphere.

[RaymondR]

Originally Posted by Dockhead

I agree with you.


A minor quibble: dilution CAN ALSO be prevention in some cases. Most pollution is putting some elements or compounds where they shouldn't be, or in too much concentration.



Dilution is not a solution where the problem is that the substance is in the wrong place -- e.g. carbon in the atmosphere.

It pretty well all came out of the atmosphere originally, we're just recycling it.

[GordMay]

Originally Posted by RaymondR

It pretty well all came out of the atmosphere originally, we're just recycling it.

What's your point?

My point would be, as Dockhead noted: "the substance is in the wrong place -- e.g. carbon (we're relocating to) in the atmosphere."

Around 20 million years ago the concentration of carbon dioxide [CO2], in the atmosphere, was below 300 parts per million [ppm].
Life on Earth has evolved under these conditions [humans did not appear until about 200,000 years ago], and atmospheric CO2 has not exceeded that concentration, until the industrial revolution brought massive CO2 [& other GHGs] emissions, from the combustion of fossil fuels: coal and oil [& later, natural gas].
The concentration of CO2 has been rising exponentially [at a rate of about 0.17% per year], since the industrial revolution, due mainly to the combustion of fossil fuel; but also to large-scale tropical deforestation, which depletes the climate system's capacity for photosynthesis.
In 2015, it passed 400 ppm, more than 40% higher than its pre-industrial value of 280 ppm [& less during ice ages], and a level that has not existed on Earth, for several million years.

What is the carbon cycle?

”... The carbon cycle describes the process in which carbon atoms continually travel from the atmosphere to the Earth and then back into the atmosphere. Since our planet and its atmosphere form a closed environment, the amount of carbon in this system does not change. Where the carbon is located — in the atmosphere or on Earth — is constantly in flux ...”

➥ https://oceanservice.noaa.gov/facts/...tml#transcript

[RaymondR]

20 million years age is less than a swift blink in the concept of geological time.

It is thought that the atmosphere once held about 7,000 ppm of CO2. Mush of this this was taken up by way of biological processes with the evolution of photosynthesis and bound up in carbonite rocks (chalks, limestones etc) petroliferous shales coals and in hydrocarbons ie, oil gas, and coal.

A side product of all this carbon capture was pretty well all the oxygen in the atmosphere.

[Chotu]

How’s that dilution concept working out for mercury (another type of toxic metal)?

[GordMay]

Originally Posted by RaymondR

20 million years age is less than a swift blink in the concept of geological time...
... It is thought that the atmosphere once held about 7,000 ppm of CO2. ...

Do you think that you would be happy, or even able to survive, in such an atmosphere [4,000 - 7,000 ppm of CO2]?


At no point, during at least the past 800,000 years [or perhaps 10 to 15 million years 1], have atmospheric CO2 levels been as high as they are now [> 400 ppm].
That means that, in the entire history of humanity [2], CO2 levels have never been this high - never mind 7,000 ppm.

[1] CO2 levels have not been as high as they are now, for [at least] the past 10 to 15 million years, during the Miocene epoch.
“Coupling of CO2 and Ice Sheet Stability Over Major Climate Transitions of the Last 20 Million Years” ~ by Aradhna K. Tripati et al

”... The concentration of atmospheric CO2 was similar to preindustrial values for the past 10 millions years, but between 15 and 20 million years ago, during the warm lower Miocene epoch, CO2 was more abundant, and major climate transitions toward cooler conditions occurred when CO2 decreased substantially...”

➥ https://www.science.org/doi/abs/10.1126/science.1178296

[2] During the Pliocene epoch, between 2 and 4.6 million years ago, Homo habilis, a possible ancestor of modern homo sapiens, arrived.
Modern human civilization didn’t arrive on the scene until the Holocene Epoch, which began about 12,000 years ago.