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Ken M
Mountain climber
Los Angeles, Ca
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Jul 21, 2016 - 07:11pm PT
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That's how I read it, too.
So right now, there are NO limits. This sets some, based upon other limits for other things that have been in place awhile.
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jul 21, 2016 - 07:57pm PT
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FYI...
EPA Radionuclide Maximum Contaminant Levels (MCLs) for drinking water...
Beta/photon emitters* 4 mrem/year
Gross alpha 15 pCi/L
Radium-226 and Radium-228 5 pCi/L
Uranium 30 μg/L or 20 pCi/L
Tritium 20,000 pCi/L
*A total of 179 individual beta particle and photon emitters may be used to calculate compliance with the MCL.
TERMS AND ABBREVIATIONS:
picoCuries per liter (pCi/L) — One trillionth of a Curie (1 Ci = 3.7 × 10^10 decays per second). 1 pCi is approximately one emission every 27 seconds. pCi/L is an activity concentration. μg/L is a mass concentration.
Alpha radiation or particle – Consists of 2 protons and 2 neutrons.
Beta radiation or particle – A negative or positive particle with the mass = electron.
Gamma or photon radiation – High energy electromagnetic radiation with no mass or charge.
Millirem (mrem) – One thousandth of a Roentgen equivalent man (rem). Dose of absorbed energy adjusted for different forms of radiation. One rem carries with it a 0.055% chance of eventually developing cancer. Doses greater than 100 rem received over a short time period are likely to cause acute radiation syndrome (ARS), possibly leading to death within weeks if left untreated. Average annual dose in US from natural background sources = 620 mrem.
Radiation dose calculator...
https://www.epa.gov/radiation/calculate-your-radiation-dose
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ontheedgeandscaredtodeath
Social climber
SLO, Ca
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Jul 22, 2016 - 08:58am PT
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EPA is probably weighing the risk of a public system providing no water with providing water with elevated rad levels in the event of an emergency.
The proposal is for a guidance document, not a change to regs or an MCL. If interested, I recommend going to the EPA website to learn about the safe drinking water act.
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jul 22, 2016 - 10:00am PT
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Yes onthedgeandscaredtodeath I think you are correct. That's the way I read it too. EPA is providing guidance for short term (days to weeks) use of drinking water in the event of an emergency related to a release of radioactive material.
This does not change any of the MCLs that I listed above that are protective of long term (70 yr time frame) human exposure.
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