# Presentation: 695182

## Challenges and Viable Options 

- Senior Radiological Engineer/WIPP
**This presentation reflects author’s personal opinions.  It does not necessarily represent the views or positions of his company and/or DOE.**

**Challenges and Viable Options **
**in Addressing Pu-241 Issues Associated with 10 CFR 835 Appendix D Values**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## What is WIPP?

-  **U.S. deep underground geological repository for safe disposal of defense TRU and TRU mixed wastes**.

**6,136 shipments**

**51,067 m****3**** TRU Wastes**

**Transportation:**

**Disposal :**

**(As of 10/8/07)**

**Characterization at **
**TRU Waste Sites**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## The final rule amends 10 CFR 835 by:

2. Excluding from the scope of 10 CFR Part 835 material, equipment, and real property approved for release in accordance with DOE approved authorized limits which has been approved by Secretarial Officer in consultation with Chief of HSS.

3. Updating the dosimetric models and dose terms to be consistent with newer recommendations from ICRP, including use of updated tissue and radiation weighting factors and updated DAC values.

- The final rule amends 10 CFR 835 by:
- 2. Excluding from the scope of 10 CFR Part 835 material, equipment, and real property approved for release in accordance with DOE approved authorized limits which has been approved by Secretarial Officer in consultation with Chief of HSS.
**3. Updating the dosimetric models and dose terms to be consistent with newer recommendations from ICRP, including use of** **updated tissue and radiation weighting factors and** **updated DAC values**.

**Final Rule for 10 CFR 835**** ****72 FR 31904, June 8, 2007**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Appendix D of 10 CFR 835

**Appendix D of 10 CFR 835**

**Group**

**1.**

**2.**

**3.**

**4.**

**5.**

*****

***Which group should Pu-241 be?**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Appendix D is Used in Identifying and Posting Contamination and High Contamination Areas (835.603) and Identifying the Need for Monitoring and Control (835.1102)

**Appendix D is Used in Identifying and Posting Contamination and High Contamination Areas (835.603) and Identifying the Need for Monitoring and Control (835.1102)**

**Group**

**1.**

**2.**

**3.**

**4.**

**5.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## The Pu-241 Decay Chain:

**The Pu-241 Decay Chain:**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Pu-241**

**Am-241**

**Np-237**

********

**21 KeV**
**14.3 yr**

****

**5.5 MeV**
**432.7 yr**

****

**4.8 MeV**
**2.1 M yr**

**Half-life:**

**Energy:**

*Hung-Cheng Chiou, Ph.D.*

## Common Challenges for Pu-241

**Common Challenges for Pu-241**

**Normal field portable beta survey instrument can not detect Pu-241 due to its low beta energy ****(max. 21 keV)**** ****.**
**Smear (for removable activity) may need to be processed and gone through radiochemical separation before applying LSC or ICP-MS to determine Pu-241 content.**
**Potential burdens (operational delay, investment in costly instrument, etc.) to all DOE Cleanup sites.**
**Potential failures to comply with 10 CFR 835 Appendix D limits.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Common Gross Alpha/Beta Counters and Probes

**Common Gross Alpha/Beta Counters and Probes**

**They can’t detect Pu-241.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Alpha/Beta Dual Probe**
**100 cm****2**** Active Area**

****** ****= ****20**** dpm**
****** ****= 52 dpm**

**Smear**

*Hung-Cheng Chiou, Ph.D.*

## Where are Appendix D Values being Used?

_**Where are Appendix D Values being Used?**_

**10 CFR 835: Occupational Radiation Protection**
**	****Transfer of materials from Controlled Area to Controlled Area.**
**DOE O 5400.5: Radiation Protection of the Public and the Environment**
**	****Transfer of materials from Controlled Area to Unrestricted Area (Free Release).**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Importance of Appendix D Values

_**Importance of Appendix D Values**_

**“****10 CFR 835.1102 Control of areas.**
**Appropriate controls**** **_**shall be maintained and verified**_** ****...**
**Any area in which contamination levels exceed the values specified in Appendix D of this part**** **_**shall be controlled**_** ****...****”**
**The burden of proof rests on each individual site performing the radiological surveys for the proper control of areas to meet Appendix D requirements.**
** **
**The fundamental question is how can one demonstrate Pu-241 content meet the criteria while the normal survey instrument can’t even detect it?**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## The Problems with Current Appendix D

_**The Problems with Current Appendix D**_

**Values are the same as the previous 10 CFR 835 which may be overly conservative or restricted.**
**Many of values in Appendix D are not consistent with ANSI/HPS N13.12-1999, Surface and Volume Radioactivity Standards for Clearance, which are **_**dose-base calculations**_** using ICRP 26/30 methods.**
**It failed to adopt (or to be consistent with) the new ICRP 60/68 methodologies which are the **_**cornerstone of this new 10 CFR 835**_** to calculate Derived Air Concentrations (DACs) for controlling radiation exposure to workers.**
**The “transuranics” category does not exclude **_**Pu-241 (a pure beta emitter) or should Pu-241 be excluded?**_

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## DOE Rational on Pu-241 Appeared on 72 FR Page 31916

**DOE Rational on ****Pu-241**** Appeared on 72 FR Page 31916**

**“****DOE agrees that eventually DOE should move toward risk based, consensus values for surface contamination values such as ANSI/HPS N13.12 values”.**
**“****DOE will continue to evaluate application of surface radioactivity values for protection of workers, the public and environment as a coordinated project that addresses both occupational and environmental aspects of this topic”.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Three Options in Addressing Pu-241 Issues

**Three Options ****in Addressing Pu-241 Issues**

**Change Option 1**
**Change Option 2**
**No Change Option**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Change Option 1

**Change Option 1**

**Group**

**1.**

**2.**

**3.**

**4.**

**5.**

*****

******* Transuranic is for alpha emitters excluding Pu-241 and Pu-241 is placed in beta-gamma emitters group.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Comparison of the Derived Screening Levels for Total Surface Radioactivity per Area (Converted from Table B.4 of ANSI N13.12-1999 using ICRP 26/30 Methodologies)

**Comparison of the Derived Screening Levels for ****Total**** Surface Radioactivity per Area ****(Converted from Table B.4 of ANSI N13.12-1999 using ICRP 26/30 Methodologies)**

**Where should Pu-241 be better assigned ?**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Concept of Derived Air Concentration (DAC) and Annual Limit on Intake (ALI)

**Concept of Derived Air Concentration (DAC) and Annual Limit on Intake (ALI)**

**DAC (********Ci/mL)**

**ALI (dpm)**

**2000 hr/yr**
**1.2 m****3****/hr**
**CED of 5 rem/yr**

**DAC-hr (mrem)**

** ****1 DAC-hr=2.5 mrem CED**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**new dosimetric**
**models**

*Hung-Cheng Chiou, Ph.D.*

## DAC, Intake, and Dose

**DAC, Intake, and Dose**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Intake 1**

**Intake 2**

**Old **
**dosimetric **
**models**

**New**
**dosimetric **
**models**

**Airborne**
**Conc. 1**

**Airborne**
**Conc. 2**

**DAC-hr**

*Hung-Cheng Chiou, Ph.D.*

**DAC**

## Comparison of the Derived Air Concentrations for Selected Group 2 Nuclides

**Comparison of the Derived Air Concentrations for Selected ****Group 2**** Nuclides**

** ****For transuranics-alpha emitters, the removable and total surface radioactivity per area can be adjusted at least ****2 folds****.**
** ****For Pu-241 (beta emitter), its radiation effect is ****at least 33 times less**** than TRU-alpha emitters.**
**This would mean that **_**Pu-241 should not be categorized in this group (~ 1320 dpm/100 cm**__**2**__** for removable)**_**.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Comparison of the Derived Air Concentrations for Selected Group 4 Nuclides

**Comparison of the Derived Air Concentrations for Selected ****Group 4**** Nuclides**

**The supports to place Pu-241 as a pure beta emitter in the Group 4 are:**
** ****Much higher tolerable total surface radioactivity for a given dose effect per ANSI N13.12 values.**
**2.****	****DAC comparison of Pu-241 to Pu-238 plus adjustment factor (from old DAC to new DAC) indicating removable limit for Pu-241 could be up to 1,320 dpm/100 cm****2****.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Change Option 1: Need Exemption Relief or HQs Action

**Change Option 1: Need Exemption Relief or HQs Action**

**Group**

**1.**

**2.**

**3.**

**4.**

**5.**

*****

******* Transuranic is for alpha emitters excluding Pu-241 and Pu-241 is placed in beta-gamma emitters group.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Support for Change Option 1: Supplemental Release Limits Approved by DOE HQs for Use at SRS

**Support for Change Option 1: Supplemental Release Limits Approved by DOE HQs for Use at SRS**

**On 10/15/03****, DOE-EH approved SRS request for supplemental release limits for **_**use in free release**_** of material at SRS in lieu of the criteria in DOE O 5400.5.**
**Followed dose-based and logics of ANSI N13.12.**
**Estimated to save over $50 M at SRS in 10 years.**

**Pu-241 was assigned in beta-gamma emitter group .**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Potential Problems with Change Option 1

**Potential Problems with Change Option 1**

**Determination of Pu-241 is still needed although the 1000 dpm/100 cm****2**** removable limit is much easier to meet.**
**Avoidance of costly new instrument and process alone will not be permitted for exemption relief.**
**Alternate monitoring methods of using marker or       ****co-detection**** should be demonstrated (Section 4.4.2, DOE G 441.1-9).**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Characterization of Waste Stream or Application of Co-Detection

**Characterization of Waste Stream or Application of Co-Detection**

**Change Option 2**
**No Change Option**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

**Two Proposed Methods in Determining Pu-241 Activity on Smear:**

## Change Option 2

**Change Option 2**

**Group**

**1.**

**2.**

**3.**

**4.**

**5.**

**40**

**1000**

**X**

**X**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Pu-241**

**Extension of Change Option 1 with more.**

*Hung-Cheng Chiou, Ph.D.*

## Major Basis for Change Option 2

**Major Basis for Change Option 2**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Double the values in TRU Category is fully in line with the new 10 CFR 835 logic and approach.**

*Hung-Cheng Chiou, Ph.D.*

## Pu-241 Decay and Am-241 In-Growth

**Pu-241 Decay and Am-241 In-Growth**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Pu-241**

**Am-241**

**Np-237**

********

**21 keV**
**14.3 yr**

****

**5.5 MeV**
**432.7 yr**

**Half-life:**

**Energy:**

*Hung-Cheng Chiou, Ph.D.*

## Is it appropriate to view Pu-241 as TRU category due to in-growth of Am-241?

**Is it appropriate to view Pu-241 as TRU category due to in-growth of Am-241?**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Time = 0**

**Time = 15 yr**

**Time = 50 yr**

**(****100 %,**** ****0 %****)**

**(****49 %,**** ****51 %****)**

**(****9 %,**** ****86 %****)**

**In term of quantity (# of particles):**

**Uptake of Pu-241: 100 dpm, N Particles**

*Hung-Cheng Chiou, Ph.D.*

## Uptake of Pu-241: 100 dpm

**Uptake of Pu-241: 100 dpm**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Time = 0**

**Time = 15 yr**

**Time = 50 yr**

**(****100 %,**** ****0 %****)**

**(****49 %,**** ****51 %****)**

**(****9 %,**** ****86 %****)**

**In term of quantity (# of particles):**

**In term of activity (dpm):**

**(****100,**** ****0****)**

**(****49,**** ****1.7****)**

**(****9,**** ****2.9****)**

**In-growth A****Am-241**** only accounts for 3% of original uptake A****Pu-241**

*Hung-Cheng Chiou, Ph.D.*

## Pu-241 Decay and Am-241 In-GrowthChanges in Particles and Activity

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Pu-241 Decay and Am-241 In-Growth****Changes in Particles and Activity**

*Hung-Cheng Chiou, Ph.D.*

## Pu-241 Decay and Am-241 In-GrowthEquations for Changes in Particles and Activity

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Pu-241 Decay and Am-241 In-Growth****Equations for Changes in Particles and Activity**

*Hung-Cheng Chiou, Ph.D.*

## Characterization of Waste Stream by Representative Sampling

**Characterization of Waste Stream by Representative Sampling**

**Step 1: Determine Pu-241 content vs. total TRU Alpha in each waste stream.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Characterization Method:

**Characterization Method:**

**Step 4: Add in-growth A****Am-241**** to gross alpha and compare the sum to Appendix D Group 2 values.**

**Step 1: Determine Pu-241 content vs. total TRU Alpha in each waste stream.**

**Step 2: Calculate Pu-241 activity of a smear and compare it to Appendix D Group 4 values:**

**Step 3: Multiply A****Pu-241**** by 0.03 to get an additional Am-241 activity due to in-growth from Pu-241 decay.**

**A****Pu-241**** = (gross ********) x  (              ) **

**A****Pu-241**** A****TRU alpha**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Example for Characterization of Representative Sampling:

**Example for Characterization of Representative Sampling:**

**e.g., A characterization of a specific waste stream from ****	****Hanford has been determined:**
**The activity ratio of Pu-241 to TRU alpha was 60/40,**
**The highest smear activity from radiological surveys showed:**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

****** ****= ****20**** dpm**
****** ****= 52 dpm**

**A****Pu-241**** = 20 dpm x (60/40) = 30 dpm.**

**4. The final TRU alpha activity = 20 + 0.9 = 20.9 dpm.**
**It is less than the “Change Option 2” Limit of 40 dpm but is greater than “No Change Option” Limit of 20 dpm.**

**3.  In-Growth A****Am-241**** = 30 x 0.03 = 0.9 dpm**

*Hung-Cheng Chiou, Ph.D.*

## Example for Characterization Method:

**Example for Characterization Method:**

- 	e.g., A smear of routine survey has results of:
- gross alpha = **20** dpm/100 cm2
- gross beta = **52** dpm/100 cm2
- Pu-241 activity =** ****30**** **dpm/100 cm2

**This smear will meet applicable limits and can be free released **
**in Change Options 1 and 2, but not in No Change Option.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

****** ****= ****20**** dpm**
****** ****= 52 dpm**

*Hung-Cheng Chiou, Ph.D.*

## Application of Co-Detection (if APu-241 in Waste Stream is Not Known)

**Application of Co-Detection ****(if A****Pu-241**** in Waste Stream is Not Known)**

**Distribution of emplaced** **TRU alpha activities at WIPP **
**over 8 years of operation (as of 6/12/07):**

**A similar determination can be made by generator site**
**using ****characterization study**** for a specific waste stream. **

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Application of Co-Detection

**Application of Co-Detection**

**(A****Pu-241**** in Waste Stream is Not Known)**

**Step 1: Determine Am-241 content in total TRU Alpha.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Range of % Am-241 in Total TRU Alpha Activities From Contact Handled (CH) and Remote-Handled (RH) Inventory

**Range of % Am-241 in Total TRU Alpha Activities From Contact Handled (CH) and Remote-Handled (RH) Inventory**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**CH Waste Streams**

**RH Waste Streams**

**Mean = 18.3 %**
**Total Tally = 642**

**Mean = 54 %**
**Total Tally = 76**

*Hung-Cheng Chiou, Ph.D.*

## Application of Co-Detection

**Application of Co-Detection**

**Step 2: Determine the activity ratio of Pu-241/Am-241 using decay chart and acceptable knowledge.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Activity Ratio of Pu-241/Am-241

**Activity Ratio of Pu-241/Am-241**

| Year |  Pu Activity | Am Activity | Pu-241/Am-241 Activity Ratio |
| --- | --- | --- | --- |
| 1 | 95.3 | 0.16 | 610 |
| 5 | 78.6 | 0.71 | 111 |
| 10 | 61.8 | 1.26 | 49.0 |
| 15 | 48.6 | 1.69 | 28.8 |
| 20 | 38.2 | 2.02 | 18.9 |
| 25 | 30.0 | 2.27 | 13.2 |
| 30 | 23.6 | 2.47 | 9.6 |
| 35 | 18.6 | 2.62 | 7.1 |
| 40 | 14.6 | 2.73 | 5.3 |
| 45 | 11.5 | 2.81 | 4.1 |
| 50 | 9.02 | 2.87 | 3.1 |
| 55 | 7.09 | 2.91 | 2.4 |
| 60 | 5.57 | 2.94 | 1.9 |
| 65 | 4.38 | 2.95 | 1.5 |
| 70 | 3.44 | 2.96 | 1.2 |

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Application of Co-Detection

**Application of Co-Detection**

**Step 3: Calculate activity of Pu-241 from a smear and compare it to Appendix D Group 4 values.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**A****Pu-241**** = (Total TRU ********) x (% Am-241) x (             ) **

**A****Pu-241**** A****Am-241**

**Acceptable Knowledge**
**(Characterization)**
**(Representative Sampling)**

**Gross ******

**Decay Chart**
**by Decay Years**

*Hung-Cheng Chiou, Ph.D.*

## Application of Co-Detection

**Application of Co-Detection**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Step 4: Multiply A****Pu-241**** by 0.03 to get an additional Am-241 activity due to in-growth from Pu-241 decay.**

**Final step: Add in-growth A****Am-241**** to gross alpha and compare the sum to Appendix D Group 2 TRU values.**

**Step 1: Determine Am-241 content in total TRU Alpha from a waste stream.**

**Step 2: Determine the activity ratio of Pu-241/Am-241 using decay chart and acceptable knowledge.**

**Step 3: Calculate activity of Pu-241 from a smear and compare it to Appendix D Group 4 values.**

**A****Pu-241**** = (Total TRU ********) x (% Am-241) x (             ) **

**A****Pu-241**** A****Am-241**

*Hung-Cheng Chiou, Ph.D.*

## Example for Application of Co-Detection:(APu-241 in Waste Stream is Not Known)

**Example for Application of Co-Detection:****(A****Pu-241**** in Waste Stream is Not Known)**

**e.g., The current retrieval operation of buried TRU ****	****wastes in 1977 (30 years ago) at Idaho has ****	****determined:**
**Maximum of 30 % Am-241 in total TRU alpha,**
**The highest smear activity from radiological surveys showed:**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

****** ****= ****20**** dpm**
****** ****= 52 dpm**

**A****Pu-241**** = 20 dpm x 0.3 x ****(9.6)**** = 57.6 dpm.**

**3.**

*Hung-Cheng Chiou, Ph.D.*

## Activity Ratio of Pu-241/Am-241

**Activity Ratio of Pu-241/Am-241**

| Year |  Pu Activity | Am Activity | Pu-241/Am-241 Activity Ratio |
| --- | --- | --- | --- |
| 1 | 95.3 | 0.16 | 610 |
| 5 | 78.6 | 0.71 | 111 |
| 10 | 61.8 | 1.26 | 49.0 |
| 15 | 48.6 | 1.69 | 28.8 |
| 20 | 38.2 | 2.02 | 18.9 |
| 25 | 30.0 | 2.27 | 13.2 |
| 30 | 23.6 | 2.47 | 9.6 |
| 35 | 18.6 | 2.62 | 7.1 |
| 40 | 14.6 | 2.73 | 5.3 |
| 45 | 11.5 | 2.81 | 4.1 |
| 50 | 9.02 | 2.87 | 3.1 |
| 55 | 7.09 | 2.91 | 2.4 |
| 60 | 5.57 | 2.94 | 1.9 |
| 65 | 4.38 | 2.95 | 1.5 |
| 70 | 3.44 | 2.96 | 1.2 |

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Example for Application of Co-Detection:(APu-241 in Waste Stream is Not Known)

**Example for Application of Co-Detection:****(A****Pu-241**** in Waste Stream is Not Known)**

**e.g., The current retrieval operation of buried TRU ****	****wastes in 1977 (30 years ago) at Idaho has ****	****determined:**
**Maximum of 30 % Am-241 in total TRU alpha,**
**The highest smear activity from radiological surveys showed:**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

****** ****= ****20**** dpm**
****** ****= 52 dpm**

**A****Pu-241**** = 20 dpm x 0.3 x (9.6) = 57.6 dpm.**

**3.**

**4.  In-Growth A****Am-241**** = 57.6 x 0.03 = 1.7 dpm**

**5. The final TRU alpha activity = 20 + 1.7 = 21.7 dpm.**
**It is less than the “Change Option 2” Limit of 40 dpm but is greater than “No Change Option” Limit of 20 dpm.**

*Hung-Cheng Chiou, Ph.D.*

## Example for Application of Co-Detection:

**Example for Application of Co-Detection:**

- 	e.g., A smear of routine survey has results of:
- gross alpha = **20** dpm/100 cm2
- gross beta = **52** dpm/100 cm2
- Pu-241 activity =** ****57.6**** **dpm/100 cm2

**This smear will meet applicable limits and can be free released **
**in Change Options 1 and 2, but not in No Change Option.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

****** ****= ****20**** dpm**
****** ****= 52 dpm**

*Hung-Cheng Chiou, Ph.D.*

## Change Option 2 is the Best Option:

**Change Option 2 is the Best Option:**

**Group**

**1.**

**2.**

**3.**

**4.**

**5.**

**This is fully in line with new 10 CFR 835 approach.**

**40**

**1000**

**X**

**X**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

**Pu-241**

*Hung-Cheng Chiou, Ph.D.*

## Change Option 2: Need Exemption Relief or HQs Action

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

****** ****= ****20**** dpm**

****** ****= ****M ****dpm**

**Gross ******

**Gross ******

**+ In-Growth A****Am-241**

**40**

**1000**

**A****Pu-241**** is compared to Group 4 values. (1000 dpm/100 cm****2**** Removable)**

**Change Option 2: Need Exemption Relief or HQs Action**

*Hung-Cheng Chiou, Ph.D.*

## No Change Option is too Restricted and Overly Conservative for Operation

**No Change Option is too Restricted and Overly Conservative for Operation**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

****** ****= ****20**** dpm**

****** ****= ****M ****dpm**

**Gross ******

**Gross ******

**+    A****Pu-241**

*Hung-Cheng Chiou, Ph.D.*

## Pathways for Suggested Change

**Pathways for Suggested Change**

**Short term solutions:**
**Individual site submits a specific application for exemption relief.**
**DOE issues a specific radiation protection technical position paper applying to all DOE sites.**
**DOE issues a clear clarification for Pu-241 in its Implementation Guidance Document for 10 CFR 835 and DOE O 5400.5.**
**2. Long term solutions:**
**DOE assembles a team of experts for a comprehensive evaluation of Appendix D and reissues new values that is consistent with dose/risk consideration.**

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Summary

**Summary**

**Three options are discussed and “Change Option 2” appears to be the best option.**
**No Change Option (Pu-241 in Group 2) is likely to paralyze the DOE Cleanup operations.**
**Transuranic values could be double (changed to 40 and 1000 dpm/100 cm****2****) for removable and total limits which are fully consistent with new 10 CFR 835 logic and approach.**
**Methods for determination of Pu-241 activity on smear are introduced.**
**By applying the characterization method or co-detection method, substantial cost-savings can be achieved for DOE Cleanup TRU Programs.**
**Comprehensive Appendix D values need to be evaluated and reissued for ****an efficient and effective**** protection of workers, the public, and environment that is consistent with dose/risk consideration.**** **

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*

## Questions or Discussion

**Questions or Discussion**

**email: chiouh@wipp.ws **

*DOE Radiation Protection Workshop, Nov. 27-29 2007*

*Hung-Cheng Chiou, Ph.D.*