# Presentation: 018420

## Technologies

** ****for**
** ****Radon **
**&**
**Radionuclide Removal**

**Tom Sorg**
**U. S. Environmental Protection Agency**

## Radionuclides

- Radium       Ra
- Uranium      U

**Radionuclides**

## Radon - 222

- Decay product of Ra 226
- Alpha emitter
- Half life of 3.8 days

**Radon - 222**

## Radon - 222

- 	Po 218    3 min
- 		Pb 214    27 min
- 			Bi 214    20 min
- 				Po 214   1.6x10-6 sec
- Pb 210   20 years

**Radon - 222**

## Radon - 222

- Naturally occurring ground water         contaminant
- Proposed MCL - 300 pCi/L
- MMM Program - 4000pCi/L (AMCL)

**Radon - 222**

## Aeration (BAT)     70 - 99 %

- GAC                       80 - 99 %

**Radon Removal Technology**

## Aeration  Technology

- High performance PP	90 - 99%
- Diffused bubble		70 - 99 %
- Tray					80 - 90 %
- Spray					80 - 90 %
- Mechanical surface	>90 %

**Aeration  Technology**

## GAC Technology

- High EBCT requirements
- Potential radiation exposure problems
- Potential waste disposal problems

**GAC Technology**
**Very Small Systems/ POU/POE**

## Radium

- 	Thorium series
- 	Alpha emitter
- 	Half life of 3.6 days
- Ra 226
- 	Uranium series
- 	Alpha emitter
- 	Half life of 1620 years

**Radium**

## Radium

- 	Thorium series
- 	Beta emitter
- 	Half life of 6.7 years

**Radium**

## Radium

- Naturally occurring ground water         contaminant
- Current MCL  - 5 pCi/L  (Ra 226 +
-  						Ra 228)

**Radium**

## Chemistry is similar to calcium and magnesium (hardness elements)

**Radium**

## Radium Removal Technology

- Lime Softening          	80 - 95 %
- Membrane Processes 	90 - 99 %
- Selective Complexers      97+ %

**Radium Removal Technology**

## Radium Removal Technology

- Ra+2 > Ba+2 > Ca+2 > Mg+2 > Na+2 > H+2
- Hardness can be used as a surrogate measurement of radium breakthrough

**Radium Removal Technology**

## Uranium

- 	Uranium series
- 	Alpha emitter
- 	Half life of 4.5x109 years
- U 234
- 	Uranium series
- 	Alpha emitter
- 	Half life of 2.5x105 years

**Uranium**

## Uranium

- 	Actinium series
- 	Alpha emitter
- 	Half life of 7.1x106 years

**Uranium**

## Uranium

- Naturally occurring ground water         contaminant
- Current MCL  - none
- Proposed MCL in 1991   	20 ug/L
- 						30 pCi/L

**Uranium**

## Uranium in Water

**  ****Chemical Forms **

- pH < 2.5            Cation    - UO2+
- pH < 2.5 - 7       Neutral  - UO2(CO3)0
- pH    7 - 10        Anion    - UO2(CO3)-2
- 					       - UO2(CO3)-4

## Uranium Removal Technology

- Lime softening           	85 - 99 %
- Anion Exchange     		90 - 99 %
- Activated Alumina    	90 - 99 %
- Membrane processes	90 - 99 %

**Uranium Removal Technology**

## Uranium Removal Technology

- Treat 10k -100k bed volumes
- Capacity sulfate dependent

**Uranium Removal Technology**

## Uranium + Radium

- Ra 100 -1500 BVs
- U   10k -100k BVs
- Adjust amount of cation / anion resin
- Optimum mixture - 10 % anion
- 					90 % cation

**Uranium + Radium**
**Removal Technology**

## Gross Alpha, Beta Particle

**Gross Alpha, Beta Particle**
** ****& Photon Emiters**

- MCLs
- Gross alpha  - 15 pCi/L (including Ra 226)
- Beta particle &
- photon emitters - 4 mrem/year

## Gross alpha             Reverse osmosis

- Beta particle & 	   Ion Exchange
- photon emitters       Reverse Osmosis

**Gross Alpha, Beta Particle**
** ****& Photon Emiters**
**BAT**

## Radon, radium & uranium are naturally occurring contaminants usually occurring in ground water.

**Radon, radium & uranium are naturally occurring contaminants usually occurring in ground water.**

## SUMMARY - RADON

**Aeration and GAC are effective treatment technologies for radon.**
**Of the two technologies, only aeration will be listed as a BAT and likely be the technology of choice in almost all cases.**
**GAC will likely be considered for only very small systems and for POU/POE.**

## SUMMARY - RADIUM

**All technologies effective for hardness removal are generally effective for radium removal.**
**Cation exchange, lime softening and reverse osmosis are the technologies currently being applied for radium removal.**

## SUMMARY - URANIUM

**Most conventional technologies have some capability for uranium removal.**
**Anion exchange has been successfully  applied for uranium removal from small ground water systems.**

## Tom Sorg

**USEPA**
**Cincinnati, OH 45268**
**513-569-7370**
**sorg.thomas@epa.gov**