Radiological Emergency Preparedness. Radiological Accident Assessment Concepts Update Workshop

Transcription

1 Radiological Emergency Preparedness Radiological Accident Assessment Concepts Update Workshop

2 Overview of PAG Manual Changes RAAC Update Workshop August

3 Overview Changes in the new PAG Manual that will affect ORO plans and procedures include: Changing the technical basis for performing dose assessments Eliminating the evacuation PAG based on thyroid dose Adding a potassium iodide (KI) administration PAG based on child thyroid dose Eliminating the 50-year objective for relocation Adding a drinking water PAG Slightly changing emergency worker guidelines Providing reentry guidelines Discussing late phase planning RAAC Update Workshop August

4 Changes to Dose Assessment Methods 1992 PAG Manual ICRP 30 dose model Included tables of dose conversion factors 2017 PAG Manual ICRP 60 dose model Defers to FRMAC calculation methods Does not include DCF tables FRMAC Assessment Manual Describes calculation methods Provides some dose parameters RAAC Update Workshop August

5 Changes to Dose Assessment Methods The FEMA REP Program, in coordination with FRMAC scientists, has developed tabulated dose parameters for common radionuclides that can be used as a tool and desk reference. Similar to the DCF tables in the 1992 PAG Manual Also developed tables for mixtures of noble gases and mixtures of iodines RAAC Update Workshop August

6 Dose Assessment Software OROs should carefully review the dose models and calculations methods used in that software to ensure the dose assessment software uses the models and methods specified in the new PAG Manual. NRC s Radiological Assessment Systems for Consequence AnaLysis (RASCAL) version program has an option to use ICRP 60 methods. RASCAL also calculates child thyroid doses. RAAC Update Workshop August

7 Thyroid Dose PAG Changes Removed the evacuation PAG based on projected thyroid dose Added PAG for administration of KI to the public Supplemental to evacuation or sheltering Reflects FDA guidance on KI in effect since 2001 Based on thyroid dose to a one-year-old child No new REP Program mandate requiring OROs that do not currently provide KI to the public to start Does not preclude an emergency manager from setting local or state protective action guidelines for actions based on specific organ or age group dose levels RAAC Update Workshop August

8 Relocation PAG Change For simplicity, the relocation PAG of 5 rem over 50 years was removed Relocation PAGs of 2 rem projected over the first year and 0.5 rem projected over any subsequent year remain For a nuclear power plant accident, taking into account decay rates, shielding from partial occupancy, and weathering, a projected dose of 2 rem in the first year is likely to amount to an actual dose of 0.5 rem or less in the second year. The application of simple dose reduction techniques would reduce the dose further. RAAC Update Workshop August

9 Drinking Water PAG Added PAG for restricting the use of contaminated water for drinking to 2017 PAG Manual For emergency situations only Two tiered 500 mrem for general population 100 mrem for pregnant women, nursing women, and children Provides derived response levels (DRLs) for Sr-90, Cs-137, and I-131 For multiple radionuclides, the dose contribution from each must be summed RAAC Update Workshop August

10 Emergency Worker Guidelines PAG Manual does not override any Federal or State regulations Most State dose limit regulations for radiation workers are similar to those found in 10 CFR 20 which are based on the older dose models and methods Other regulations such as 29 CFR 1920 may also apply to responders Changes 10 rem guideline from protecting valuable property to protecting critical infrastructure necessary for public welfare Prior to exceeding 5 rem guideline, each emergency worker should make an informed decision as to how much radiation risk they are willing to accept RAAC Update Workshop August

11 Reentry Guidelines The new PAG Manual provides an extensive Reentry Matrix listing suggested dose guidelines for various activities. A simplified version is shown below. RAAC Update Workshop August

12 Late Phase Guidance Begins when cleanup and recovery actions have begun and ends when all recovery actions have been completed May extend for months to years Proceeds independently of intermediate phase protective action activities Aimed at both reducing longer-term exposures and improving interim living conditions Final cleanup decisions are made and final recovery efforts are implemented Decisions should be made with stakeholder involvement Balance health protection with the desire of the community to resume normal life RAAC Update Workshop August

13 Implementation Strategy Once FEMA has evaluated the impact of all the changes in the new PAG Manual, we will set an implementation timeline for OROs OROs may adopt the guidance in the new PAG Manual at any time OROs should ensure that any changes to its plans and procedures are consistent with the plans and procedures of other OROs and the utility Any changes to ORO plans and procedures should include all applicable changes in the PAG Manual For example, an ORO should not remove evacuation decisions based on thyroid dose without also changing dose assessment methods RAAC Update Workshop August

14 FEMA REP Training and Assistance Frequently Asked Questions (FAQ) Regarding REP Program Implementation of the Updated PAG Manual PER-316 Radiological Accident Assessment Concepts (RAAC) Course Updated to reflect new dose assessment models and methods RAAC Update Workshop One-day workshop for those who have recently taken RAAC course Other REP Program courses being updated MGT-445 REP Plume Plan Review (RPPR) Course MGT-453 REP Post-Plume Plan Review (RPPR) Course RAAC Update Workshop August

15 RAAC Unit 2 Principles of Atmospheric Dispersion RAAC Update Workshop August

16 Unit 2 What You Learned Atmospheric Dispersion Atmospheric Transport Atmospheric Diffusion RAAC Update Workshop August

17 Variables and Equations Equation Variables Q e Source Term (Ci/sec) Base of the natural logarithm Wind speed (m/sec) Concentration (Ci/m 3 ) y x, y, z S.D. of the crosswind concentration distribution Cartesian coordinates z S.D. of the vertical concentration distribution χ 2 2 y z-h ( ) = Q σy σz x,y,z;h e πσyσzμ Equation Variables Visual 2-20 Principles of Atmospheric Dispersion Radiological Accident Assessment Concepts Gaussian Equations Generalized Gaussian Equation Visual 2-21 Principles of Atmospheric Dispersion Radiological Accident Assessment Concepts RAAC Update Workshop August

18 Stability Classes Reduction Factors Stability Classes and Reduction Factors Stability Classification Extremely Unstable Moderately Unstable Slightly Unstable Neutral Slightly Stable Moderately Stable Extremely Stable Pasquill Categories A B C D E F G Visual 2-27 Principles of Atmospheric Dispersion Radiological Accident Assessment Concepts Refer to Appendix pp. 1 & 15 RAAC Update Workshop August

19 Workbook of Atmospheric Dispersion Estimates Horizontal Dispersion Coefficient Vertical Dispersion Coefficient A Stability B Stability C Stability D Stability E Stability F Stability Refer to Appendix pp RAAC Update Workshop August

20 Unit 2 Significant Changes Deposition Velocity Values FRMAC Values NRC Iodine Partitioning RAAC Update Workshop August

21 Ground Deposition W d = * V d * Time V d = Deposition velocity (cm/sec) V d default values Noble Gases 0 cm/s Particulate Iodine 0.65 cm/s Iodine Vaper/Reactive Gas (I 2 ) 0.64 cm/s Methyl Iodide/Non-reactive gas (CH 3 I) 0 cm/s Other Particulates cm/s Dry Deposition Equation Iodine Average cm/s RAAC Update Workshop August

22 RAAC Unit 3 Early Phase Dose Projection Procedures RAAC Update Workshop August

23 Unit 3 What You Learned Information Needed for Dose Calculations Dose Projection Procedures Air Concentrations from Source Term and Meteorology Dose Conversion Factors for Individual Pathways Dose Conversion Factors for Combined Pathways DRD to TEDE Correction Factors RAAC Update Workshop August

24 Information Needed for Dose Calculations Dose Calculation Process Dose Projection Calculation Information Needed for Dose Calculations Dose Projection Calculation Process Source Term Information Meteorological Information 1 2 Determine Q,, and Stability Class Calculate Dose Conversion Factor Information 3 4 Calculate in Calculate Projected Dose Visual 3-9 Early Phase Dose Projection Procedures Radiological Accident Assessment Concepts Visual 3-17 Early Phase Dose Projection Procedures Radiological Accident Assessment Concepts RAAC Update Workshop August

25 Finding /Q Scenario: Meteorology Information (cont.) /Q (m -2 ) Ground Level Release with 1250-meter Lid Distance Downwind mi km A B C D E F E 6 3.0E 5 7.6E 5 2.1E 4 4.2E 4 9.6E E 6 7.4E 6 2.1E 5 7.0E 5 1.4E 4 3.3E E 7 1.9E 6 6.1E 6 2.4E 5 5.0E 5 1.2E E 7 8.4E 7 2.9E 6 1.3E 5 2.8E 5 6.8E E 7 4.8E 7 1.7E 6 8.5E 6 1.9E 5 4.6E E 7 3.3E 7 1.2E 6 6.1E 6 1.4E 5 3.3E E 7 2.5E 7 6.3E 7 3.7E 6 8.4E 6 2.2E 5 Stability Chart Graphs Appendix Table Refer to Appendix page A-13 Visual 3-2 Early Phase Dose Projection Procedure Radiological Accident Assessment Concep Refer to Appendix pp RAAC Update Workshop August

26 The Blue Sheet BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I E RAAC Update Workshop August

27 Finding Dose Conversion Factors Dose conversion factors for mixtures of NOBLE GAS as a function of time after shutdown and expected exposure time T ime after shutdown release starts (hours) Gross Noble Gas Dose Conversion Factor (rem per Ci cm 3 hr) Estimated Exposure Time (hours) E+2 2.4E+2 2.2E+2 1.9E+2 1.5E E+2 2.0E+2 1.9E+2 1.6E+2 1.2E E+2 1.7E+2 1.6E+2 1.4E+2 1.1E E+2 1.2E+2 1.1E+2 1.0E+2 7.7E E+1 5.9E+1 5.6E+1 5.1E+1 4.2E+1 Dose conv ersion factor for Kr-87 is 5.1E+2. Use of Kr-87 dose conv ersion factor is conserv ativ e. EPA PAG Manual Tables for Individual Isotopes Refer to Appendix page A-14 Appendix Tables for Mixtures of Noble Gases and Iodines Visual 3-70 Early Phase Dose Projection Procedures Radiological Accident Assessment Concepts RAAC Update Workshop August

28 DRD to TEDE Correction Factor (CF) CF = EDE immersion EDE groundshine CEDE+ EDE immersion EDE groundshine * RAAC Update Workshop August

29 Unit 3 Significant Changes Basis for Dose Projections ICRP 60 dose model PAG Manual defers to FRMAC calculation methods PAG Manual does not include DCF tables Now in RAAC Appendix Changes in terminology 1 R = 1 rem Thyroid dose PAG changes Removed the evacuation PAG based on projected thyroid dose Added PAG for administration of KI to the public Supplemental to evacuation or sheltering Reflects FDA guidance on KI in effect since 2001 Based on thyroid dose to a one-year-old child RAAC Update Workshop August

30 EPA Protective Action Guides Pathway General public, under normal weather conditions: PAG (rem) Protective Actions TED (Based on an Adult Male) (Immersion ED + 4-day Deposition ED + Inhalation CED) 1 Evacuation or Shelter-in- Place COED thyroid (Based on Child) 5 Supplimentary Administration of KI General public, under unusually hazardous environmental conditions: TED (Based on an Adult Male) (Immersion ED + 4-day Deposition ED + Inhalation CED) Special groups, under normal weather conditions: TED (Based on an Adult Male) (Immersion ED + 4-day Deposition ED + Inhalation CED) Special groups, under unusually hazardous environmental conditions: TED (Based on an Adult Male) (Immersion ED + 4-day Deposition ED + Inhalation CED) Evacuation or Shelter-in- Place Evacuation or Shelter-in- Place Evacuation or Shelter-in- Place RAAC Update Workshop August

31 Basis for Dose Parameters ICRP Publication 119, Compendium of Dose Coefficients Based on ICRP Publication 60, October 2011 FRMAC Assessment Manual, Volume 1 Overview and Methods, April 2015 RAAC Update Workshop August

32 Basis for Dose Conversion Factors Dosimetry for all the PAGs was updated using the International Commission on Radiological Protection (ICRP) Publication 60 series Doses are calculated using the values and methods contained in the Federal Radiological Monitoring and Assessment Center (FRMAC) Assessment Manuals FRMAC uses the term Dose Parameter (DP) rather than Dose Conversion Factor RAAC Update Workshop August

33 Assumed Values Used by FRMAC Breathing rate = 1.5 m 3 /hr Deposition velocity Iodine = cm/s Particulates = 0.3 cm/s Gamma shielding due to roughness = 0.82 Period that the public receives dose from deposited materials before relocation is 4 days (96 hours) RAAC Update Workshop August

34 Assumed Values Used by FRMAC Iodine Physical Form: 0.25 Particulate (I - ion or salt) 0.3 Reactive Gas (I 2 ) 0.45 Non-Reactive Gas (CH 3 I) Based on NRC assumptions RAAC Update Workshop August

35 Scenario: Air Concentrations from Source Term and Meteorology A reactor site releasing 4 curies per second of Iodine 131 ( 131 I) at ground level The wind speed is 14 mph from 195, stability class is C with a mixing lid at 1250 meters What is the concentration at 5 miles? RAAC Update Workshop August

36 Scenario: Source Term Information Dose projection at 5 miles BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I RAAC Update Workshop August

37 Scenario: Meteorology Information 1. Convert mi to km 2. Move across the x-axis 3. Move up on the y-axis to the H=0 line 4. Locate the value for /Q Refer to Appendix pg. 7 RAAC Update Workshop August

38 Scenario: Meteorology Information (cont.) /Q (m -2 ) Ground Level Release with 1250-meter Lid Distance Downwind mi km A B C D E F E 6 3.0E 5 7.6E 5 2.1E 4 4.2E 4 9.6E E 6 7.4E 6 2.1E 5 7.0E 5 1.4E 4 3.3E E 7 1.9E 6 6.1E 6 2.4E 5 5.0E 5 1.2E E 7 8.4E 7 2.9E 6 1.3E 5 2.8E 5 6.8E E 7 4.8E 7 1.7E 6 8.5E 6 1.9E 5 4.6E E 7 3.3E 7 1.2E 6 6.1E 6 1.4E 5 3.3E E 7 2.5E 7 6.3E 7 3.7E 6 8.4E 6 2.2E 5 Refer to Appendix pg. 11 RAAC Update Workshop August

39 Scenario: Source Term Information Dose projection at 5 miles BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I E RAAC Update Workshop August

40 Scenario: Source Term Information Dose projection at 5 miles BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I E E-7 RAAC Update Workshop August

41 Scenario: Air Concentrations from Source Term and Meteorology Assume the release lasts 8 hours, what is the integrated air concentration at 5 miles? RAAC Update Workshop August

42 Scenario: Source Term Information Dose projection at 5 miles BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I E E E-6 RAAC Update Workshop August

43 Dose: Time-Integrated Concentrations and Dose Parameters integrated * DP = Dose (rem) RAAC Update Workshop August

44 FRMAC defines four Primary Pathways From Airborne Materials External exposure from plume submersion Inhalation of plume-borne materials From Deposited Materials External exposure from groundshine Inhalation of resuspended materials Not significant during the early phase of a NPP incident RAAC Update Workshop August

45 Gamma Exposure from Plume Immersion Dose parameters yield effective dose (ED) Short-lived daughters are accounted for For stochastic effects FRMAC applies the conversion 1 R = 1 rem RAAC Update Workshop August

46 Scenario: Air Concentrations from Source Term and Meteorology What are the immersion, inhalation, 96 hour groundshine, 96 hour resuspension, and whole body (TED) doses to an adult at 5 miles? What is the plume inhalation thyroid dose to a 1 year old at 5 miles? RAAC Update Workshop August

47 Nuclide Pathway & Table I-131 Immersion 6.2E-6 Inhalation Deposition Resuspension BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) 6.2E-6 6.2E-6 6.2E-6 TED 6.2E-6 Subtotal: TED for all radionuclides: RAAC Update Workshop August

48 Refer to Appendix pgs RAAC Update Workshop August

49 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) I-131 Immersion 6.2E-6 2.3E2 Inhalation 6.2E-6 8.2E4 Deposition 6.2E-6 4.1E3 Resuspension 6.2E-6 2.3E2 TED 6.2E-6 8.6E4 Subtotal: TED for all radionuclides: RAAC Update Workshop August

50 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) I-131 Immersion 6.2E-6 2.3E2 1.4E-3 Inhalation 6.2E-6 8.2E4 5.1E-1 Deposition 6.2E-6 4.1E3 2.5E-2 Resuspension 6.2E-6 2.3E2 1.4E-3 TED 6.2E-6 8.6E4 5.3E-1 Subtotal: TED for all radionuclides: RAAC Update Workshop August

51 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) I-131 Immersion 6.2E-6 2.3E2 1.4E-3 Inhalation 6.2E-6 8.2E4 5.1E-1 Deposition 6.2E-6 4.1E3 2.5E-2 Resuspension 6.2E-6 2.3E2 1.4E-3 TED 6.2E-6 8.6E4 5.3E-1 In all cases with a NPP, resuspension will contribute less than 10% of the total. We will normally ignore it in our early phase calculations. Subtotal: TED for all radionuclides: RAAC Update Workshop August

52 BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I E E E-6 Nuclide Pathway & Table χ in * DCF = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) Subtotal: Iodine-131 (Thyroid) Child 6.2E-6 TED for all radionuclides: COED Thyroid: RAAC Update Workshop August

53 Committed Organ Equivalent Dose = COED Refer to Appendix pg. 24 RAAC Update Workshop August

54 BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I E E E-6 Nuclide Pathway & Table χ in * DCF = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) Iodine-131 (Thyroid) Subtotal: TED for all radionuclides: Child 6.2E-6 3.2E6 COED Thyroid: RAAC Update Workshop August

55 BLUE SHEET SC=_C_ χ /Q * Q = χ * t = χ in 5 mi (m -2 ) (Ci/sec) 5 mi ( Ci/cm 3 ) 5 mi ( Ci * cm -3 * hr) I E E E-6 Nuclide Pathway & Table χ in * DCF = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) Iodine-131 (Thyroid) Subtotal: TED for all radionuclides: Child 6.2E-6 3.2E6 20 COED Thyroid: RAAC Update Workshop August

56 Scenario: Air Concentrations from Source Term and Meteorology Source terms are not single radionuclides and they are not usually reported as individual radionuclides. So... We have modeled dose parameters for mixes in some tables RAAC Update Workshop August

57 Scenario: Air Concentrations from Source Term and Meteorology A reactor site is experiencing a ground-level release of 700 Ci/sec of Noble Gas, 1.5 Ci/sec of Halogens (Iodine), and 0.5 Ci/sec of Particulate 5 hours after reactor shutdown The wind speed is 4 mph, from 360, the stability class is D and the mixing lid is 1250 meters Assume exposure time lasts two hours What are the concentrations at 2 miles? RAAC Update Workshop August

58 Scenario Source term (Q) NG: 700 Ci/sec I: 1.5 Ci/sec P: 0.5 Ci/sec Transport ( ) 1.8 m/sec Stability Class D Holdup time (time since Rx shutdown) 5 hr Exposure time (t) 2 hr Point of interest 2 miles down wind on centerline RAAC Update Workshop August

59 Scenario: Source Term Information Dose projection at 2 miles BLUE SHEET SC=_D_ χ /Q * Q = χ * t = χ in 2 mi (m -2 ) (Ci/sec) 2 mi ( Ci/cm 3 ) 2 mi ( Ci * cm -3 * hr) NG Mix I Mix Particulate RAAC Update Workshop August

60 Scenario: Meteorology Information (cont.) /Q (m -2 ) Ground Level Release with 1250-meter Lid Distance Downwind mi km A B C D E F E 6 3.0E 5 7.6E 5 2.1E 4 4.2E 4 9.6E E 6 7.4E 6 2.1E 5 7.0E 5 1.4E 4 3.3E E 7 1.9E 6 6.1E 6 2.4E 5 5.0E 5 1.2E E 7 8.4E 7 2.9E 6 1.3E 5 2.8E 5 6.8E E 7 4.8E 7 1.7E 6 8.5E 6 1.9E 5 4.6E E 7 3.3E 7 1.2E 6 6.1E 6 1.4E 5 3.3E E 7 2.5E 7 6.3E 7 3.7E 6 8.4E 6 2.2E 5 Refer to Appendix pg. 11 RAAC Update Workshop August

61 Scenario: Air Concentrations ( ) Dose projection at 2 miles BLUE SHEET SC=_D_ χ /Q * Q = χ * t = χ in 2 mi (m -2 ) (Ci/sec) 2 mi ( Ci/cm 3 ) 2 mi ( Ci * cm -3 * hr) NG Mix 2.4E I Mix 2.4E Part 2.4E RAAC Update Workshop August

62 Scenario: Air Concentrations ( ) Dose projection at 2 miles BLUE SHEET SC=_D_ χ /Q * Q = χ * t = χ in 2 mi (m -2 ) (Ci/sec) 2 mi ( Ci/cm 3 ) 2 mi ( Ci * cm -3 * hr) NG Mix 2.4E E-3 I Mix 2.4E E-5 Cs E E-6 RAAC Update Workshop August

63 Scenario: Air Concentrations from Source Term and Meteorology What are the integrated air concentrations of Noble Gas, Iodines, and Particulates at 2 miles? RAAC Update Workshop August

64 Scenario: Time-Integrated Air Concentrations Dose projection at 2 miles BLUE SHEET SC=_D_ χ /Q * Q = χ * t = χ in 2 mi (m -2 ) (Ci/sec) 2 mi ( Ci/cm 3 ) 2 mi ( Ci * cm -3 * hr) NG Mix 2.4E E-3 2 I Mix 2.4E E-5 2 Part 2.4E E-6 2 RAAC Update Workshop August

65 Scenario: Time-Integrated Air Concentrations Dose projection at 2 miles BLUE SHEET SC=_D_ χ /Q * Q = χ * t = χ in 2 mi (m -2 ) (Ci/sec) 2 mi ( Ci/cm 3 ) 2 mi ( Ci * cm -3 * hr) NG Mix 2.4E E E-2 I Mix 2.4E E E-5 Part 2.4E E E-5 RAAC Update Workshop August

66 Scenario What are the projected individual pathway and total doses to a member of the public 2 miles down wind? RAAC Update Workshop August

67 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 I Mix Immersion: 4.00E-5 Part Immersion: 1.33E-5 NG Mix Inhalation: 1.87E-2 I Mix Inhalation: 4.00E-5 Part Inhalation: 1.33E-5 NG Mix Deposition: 1.87E-2 I Mix Deposition: 4.00E-5 Part Deposition: 1.33E-5 Subtotal: Subtotal: Subtotal: TED for all radionuclides: RAAC Update Workshop August

68 Scenario Source term (Q) NG: 700 Ci/sec I: 1.5 Ci/sec P: 0.5 Ci/sec Assume all particulate is Cs-137 Transport ( ) 1.8 m/sec Exposure time (t) 2 hr Holdup time (time since Rx shutdown) 5 hr Dose parameters for mixtures Dose parameters for individual nuclides RAAC Update Workshop August

69 Refer to Appendix pg. 21 RAAC Update Workshop August

70 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 I Mix Immersion: 4.00E-5 Part Immersion: 1.33E-5 NG Mix Inhalation: 1.87E-2 0 I Mix Inhalation: 4.00E-5 Part Inhalation: 1.33E-5 NG Mix Deposition: 1.87E-2 0 I Mix Deposition: 4.00E-5 Part Deposition: 1.33E-5 Subtotal: Subtotal: Subtotal: TED for all radionuclides: RAAC Update Workshop August

71 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 Part Immersion: 1.33E-5 Subtotal: NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 Part Inhalation: 1.33E-5 Subtotal: NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 Part Deposition: 1.33E-5 Subtotal: TED for all radionuclides: RAAC Update Workshop August

72 Refer to Appendix pg. 21 RAAC Update Workshop August

73 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 7.5E2 Part Immersion: 1.33E-5 Subtotal: NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 2.2E4 Part Inhalation: 1.33E-5 Subtotal: NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 2.3E3 Part Deposition: 1.33E-5 Subtotal: TED for all radionuclides: RAAC Update Workshop August

74 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 7.5E2 3.0E-2 Part Immersion: 1.33E-5 Subtotal: NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 2.2E4 8.8E-1 Part Inhalation: 1.33E-5 Subtotal: NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 2.3E3 9.2E-2 Part Deposition: 1.33E-5 Subtotal: TED for all radionuclides: RAAC Update Workshop August

75 Among available particulates, Cesium is normally the most significant contributor to dose. Half lives are long enough that several days does not significantly alter the ratio Refer to Appendix pg. 22 RAAC Update Workshop August

76 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 7.5E2 3.0E-2 Part Immersion: 1.33E-5 7.9E2 Subtotal: NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 2.2E4 8.8E-1 Part Inhalation: 1.33E-5 2.9E4 Subtotal: NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 2.3E3 9.2E-2 Part Deposition: 1.33E-5 1.4E4 Subtotal: TED for all radionuclides: RAAC Update Workshop August

77 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 7.5E2 3.0E-2 Part Immersion: 1.33E-5 7.9E2 1E-2 Subtotal: 2.6 NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 2.2E4 8.8E-1 Part Inhalation: 1.33E-5 2.9E4 3.8E-1 Subtotal: 1.3 NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 2.3E3 9.2E-2 Part Deposition: 1.33E-5 1.4E4 1.8E-1 Subtotal: TED for all radionuclides: 2.7E-1 RAAC Update Workshop August

78 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 7.4E2 3.0E-2 Part Immersion: 1.33E-5 7.9E2 1E-2 Subtotal: 2.6 NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 2.2E4 8.8E-1 Part Inhalation: 1.33E-5 2.9E4 3.8E-1 Subtotal: 1.3 NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 2.4E3 9.6E-2 Part Deposition: 1.33E-5 1.4E4 1.8E-1 Subtotal: 2.7E-1 TED for all radionuclides: 4.2 RAAC Update Workshop August

79 DRD to TED Correction Factor (CF) CF = CED + ED immersion ED groundshine ED immersion ED groundshine * 1 rem R RAAC Update Workshop August

80 Using TED Correction Factor (CF) CF * DRD Reading = TED Dose Limit CF = Exposure Limit RAAC Update Workshop August

81 Scenario: DRD Correction Factor (CF) Use the values from the Individual Pathways scenario to calculate a DRD correction factor RAAC Update Workshop August

82 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 7.4E2 3.0E-2 Part Immersion: 1.33E-5 7.9E2 1E-2 Subtotal: 2.6 NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 2.2E4 8.8E-1 Part Inhalation: 1.33E-5 2.9E4 3.8E-1 Subtotal: 1.3 NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 2.4E3 9.6E-2 Part Deposition: 1.33E-5 1.4E4 1.8E-1 Subtotal: 2.7E-1 TED for all radionuclides: 4.2 RAAC Update Workshop August

83 Scenario: DRD Correction Factor (CF) Assuming that no KI is take by the emergency worker CF = CED + ED immersion ED groundshine ED immersion ED groundshine 1 rem R CF = 1.3 rem +2.6 rem rem 2.6 rem rem * 1 rem R = RAAC Update Workshop August

84 Scenario: DRD Correction Factor (CF) Assuming that no KI is take by the emergency worker CF = rem +2.6 rem rem rem rem * 1 rem R 3.9 / 2.6 = 1.5 rem/r = RAAC Update Workshop August

85 Nuclide Pathway & Table BLUE SHEET χ in * DP = Dose ( Ci * cm -3 * hr) rem per ( Ci * cm -3 * hr) (rem) NG Mix Immersion: 1.87E-2 1.4E2 2.6 I Mix Immersion: 4.00E-5 7.4E2 3.0E-2 Part Immersion: 1.33E-5 7.9E2 1E-2 Subtotal: 2.6 NG Mix Inhalation: 1.87E I Mix Inhalation: 4.00E-5 2.2E4 8.8E-1 Part Inhalation: 1.33E-5 2.9E4 3.8E-1 Subtotal: 1.3 NG Mix Deposition: 1.87E I Mix Deposition: 4.00E-5 2.4E3 9.6E-2 Part Deposition: 1.33E-5 1.4E4 1.8E-1 Subtotal: 2.7E-1 TED for all radionuclides: 4.2 RAAC Update Workshop August

86 Scenario: DRD Correction Factor (CF) If your emergency workers have taken KI Subtract 90% of Iodine CED from the TED 3.8 rem rem x.9 = 3.0 rem 3.0 rem / 2.6 rem = 1.2 rem/r There are several ways to display the math, they get to the same place RAAC Update Workshop August

87 RAAC Unit 4 Field Team Dose Projection Validation RAAC Update Workshop August

88 Unit 4 What You Learned Fission Products: Nuclear and Chemical Properties Ambient Monitoring Air Sampling Concentration Calculations Data Collection Tactics RAAC Update Workshop August

89 Fission Products Have too many neutrons in their nuclei Are unstable Balance their nuclei by converting neutrons to protons All produce β particles Most produce γ rays RAAC Update Workshop August

90 Ambient Monitoring Make predictions Verify predictions with data from field monitoring teams RAAC Update Workshop August

91 Air Sampling RAAC Update Workshop August

92 Concentration Calculations C = ASV cm 3 GC BC CE DE 2.22E6 dpm µci RAAC Update Workshop August

93 Concentration Calculations (cont.) Gather Field Data Calculate Air Sample Activity Calculate Concentration and Centerline Activity Calculate Dose to the Public Calculate DRD to TEDE Correction Factor RAAC Update Workshop August

94 Concentration Calculations (cont.) Plume Spread Equation from Centerline: y = 2ln Plume Spread Equation Rewritten to Determine the Ratio from the Off-Centerline Field Measurements: X o X y = e x o x y 0.5 y 2 2 σ y 2 σ y RAAC Update Workshop August

95 Unit 4 Significant Changes DRD to TED Correction Factor (CF) 1 R = 1 rem RAAC Update Workshop August

96 Calculate DRD to TED Correction Factor DRD to TED Correction Factor (CF) for measured (not modeled) exposure rate CF = CED+ED measured ED measured rem R RAAC Update Workshop August

97 Calculate DRD to TED Correction Factor Example: Measured exposure rate = 100 mr/hr ED for 1 hour in plume = 100 mrem Calculated doses from air sample results CED from Iodine for 1 hour in plume = 140 mrem CED from particulates for 1 hour in plume = 29 mrem CF = 169 mrem+100 mrem CF =2.7 rem R 100 mrem rem R RAAC Update Workshop August

98 The CF Applied in Practice: DRD reading that equals the dose limit (e.g. 5 rem) = (dose limit in rem)/(cf) DRD reading that equals the dose limit = (5 rem)/(2.7 rem/r) = 1.8 R If all of our emergency workers take KI effectively, then apply a 90% reduction for the Iodine contribution to CED (only 10% of the dose is received) (1.4E-1 rem) * 0.1 = 1.4E-2 rem 2.9E-2 rem + 1.4E-2 rem = 4.3E-2 rem CF = * 1 rem R = 1.4 rem/r (5 rem)/(1.4 rem/r) = 3.6 R is the new calculated administrative dose limit RAAC Update Workshop August

99 RAAC Unit 5 RASCAL for the Early Phase RAAC Update Workshop August

100 Unit 5 What You Learned Introduction to RASCAL Primary Tool #1: STDose Primary Tool #2: FMDose RAAC Update Workshop August

101 Unit 5 Significant Changes Use of ICRP 60 values in RASCAL RAAC Update Workshop August

102 RASCAL vs. EPA Dose Projection Method RASCAL EPA Defaults to dose factors from Federal Guidance Report FGR-11 (ICRP 26) Uses FRMAC Assessment Manual methodology Has ICRP 60 Dose Parameters Option ICRP 60 methods and Dose Parameters RAAC Update Workshop August

103 Calculating Doses RAAC Update Workshop August

104 RAAC Unit 7 EPA Relocation PAGs and DRLs RAAC Update Workshop August

105 Unit 7 What You Learned EPA PAGs and Incident Phases The Assessment Process How to Calculate DRLs Implementation of EPA Relocation PAGs and Intermediate Phase Protective Measures RAAC Update Workshop August

106 EPA PAGs and Incident Phases Early Phase Has its own PAGs Intermediate Phase Has its own PAGs Late Phase Does not have Federal PAGs In all phases, the PAGs are independent of those for the previous phase. RAAC Update Workshop August

107 The Assessment Process The Assessment Process Gathering Data Obtaining Dose Conversion Factors Using Dose Conversion Factors The Assessment Process Visual 7-25 EPA Relocation PAGs and DRLs Radiological Accident Assessment Concepts RAAC Update Workshop August

108 Projecting Dose Nuclide Concentration (pci/m 2 ) DCF (mrem per pci/m 2 ) Dose (mrem) * 1 st -year DCF = * 2 nd -year DCF = * 50-year DCF = RAAC Update Workshop August

109 Projecting CEDE from Airborne Concentration Airborne Concentration = (Ground Deposition) * (Resuspension Factor) Nuclide Concentration (pci/m 3 ) DCF (mrem per pci/m 3 ) Dose (mrem) * 1 st -year DCF = * 2 nd -year DCF = RAAC Update Workshop August

110 DRLs The gamma exposure rates at 1 meter above the surface that, based on the nuclide mix, equal the relocation PAG and the second year and 50-year long-term objectives. RAAC Update Workshop August

111 Incident-Specific DRL Calculation STEPS: 1. Sample Radionuclide Concentration * DCF = Dose 2. Dose Calculated Exposure Rate at 1m = Incident Specific DCF 3. PAG Incident Specific DCF = Incident Specific DRL RAAC Update Workshop August

112 Implementation of Relocation PAGs Recommended Priorities: Protect all persons from doses that could cause acute health effects. Recommend simple decontamination techniques and staying indoors. Give priority to persons residing in areas with high exposure rate, pregnant women, and preschoolers. RAAC Update Workshop August

113 Dose Reduction Factors Net Reduction Factor: 0.6 Decontamination Factor: 0.7 RAAC Update Workshop August

114 Unit 7 Significant Changes PAG Changes Second year dose now a PAG 50-year objective eliminated New Dose Parameters Based on ICRP 60 and FRMAC calculation methods Tables in Appendix Updated Emergency Worker Guidelines Reentry Guidelines Late Phase Guidance RAAC Update Workshop August

115 The Six Rs Restricted Zone (RZ) An area with controlled access from which the population has been relocated Relocation The removal or continued exclusion of people (households) from contaminated areas to avoid chronic radiation exposure RAAC Update Workshop August

116 The Six Rs (cont.) Return Permanent resettlement in evacuation or relocation areas with no restrictions, based on acceptable environmental and public health conditions Reentry Temporary entry into a restricted zone (RZ) under controlled conditions RAAC Update Workshop August

117 The Six Rs (cont.) Reoccupancy The return of households and communities to relocation areas during the cleanup process, at radiation levels acceptable to the community Recovery The process of reducing radiation exposure rates and concentrations in the environment to acceptable levels for unconditional occupancy or use RAAC Update Workshop August

118 Intermediate Phase Relocation PAGs 1 st Year 2 rem TED 2 nd Year 500 mrem TED Refer to Appendix pg. 17 RAAC Update Workshop August

119 Uses of 1 st and 2 nd Year Dose Projections: 1st year dose projections: Compared to the relocation PAG Relocation warranted if projection > PAG 2 nd (and subsequent) year dose projections: Used to determine if protective actions other than relocation are warranted May warrant relocation if dose reduction efforts are not effective RAAC Update Workshop August

120 Obtaining Dose Parameters Refer to the Appendix for dose parameters for common radionuclides Gathering Data Obtaining dose parameters Using dose parameters Refer to Appendix pg. 25 RAAC Update Workshop August

121 Dose Parameter Tables Intermediate Phase Dose Parameters for Various Pathways Decay and Weathering Intermediate Phase Dose Parameters for Various Pathways Decay Only (No Weathering) Tables include values for groundshine and resuspension dose parameters and initial exposure rate Refer to Appendix pgs RAAC Update Workshop August

122 Using Dose Parameters Different dose parameters are needed for projecting dose for the two time frames Dose parameters permit calculating a DRL for each time frame Gathering Data Obtaining dose parameters Using dose parameters RAAC Update Workshop August

123 Projecting ED (Decay Only) Nuclide Concentration (pci/m 2 ) DP (mrem per pci/m 2 ) Dose (mrem) * 1 st -year DP = * 2 nd -year DP = Refer to Appendix pg. 26 RAAC Update Workshop August

124 Projecting ED (Decay Only) (cont.) Nuclide Concentration (pci/m 2 ) DP (mrem per pci/m 2 ) Dose (mrem) Cs E+6 * 1 st -year DP 5.2E-5 = E+6 * 2 nd -year DP 5.1E-5 = 350 RAAC Update Workshop August

125 Projecting ED (Decay & Weathering) Nuclide Concentration (pci/m 2 ) DP (mrem per pci/m 2 ) Dose (mrem) * 1 st -year DP = * 2 nd -year DP = Refer to Appendix pg. 25 RAAC Update Workshop August

126 Projecting ED (Decay & Weathering) (cont.) Nuclide Concentration (pci/m 2 ) DP (mrem per pci/m 2 ) Dose (mrem) Cs E+6 * 1 st -year DP 4.8E-5 = E+6 * 2 nd -year DP 4.0E-5 = 270 RAAC Update Workshop August

127 Comparison of ED Projections Decay Only Decay & Weathering 1 st year 350 mrem 330 mrem 2 nd year 350 mrem 270 mrem RAAC Update Workshop August

128 Projecting CED Airborne Concentration = (Ground Deposition) * (Resuspension Factor) Default resuspension factor: K t = (1.0E-5 * e -8.1E-7*t )+(7.0E-9 * e -2.31E-8*t )+1.0E-9 K t = Resuspension Factor, the fraction of radioactive material transferred from the surface to the breathing zone at a given time (t) after initial deposition, m -1 ; and t = Time, the time elapsed from initial deposition, s. RAAC Update Workshop August

129 Projecting CED (cont.) Default resuspension factor incorporated in CED DPs If default is correct, dose from inhalation of resuspended material will be much less than ten percent of total dose (for NPP accidents) Air samples should be taken to confirm RAAC Update Workshop August

130 Projecting CED (cont.) EXAMPLE: Cs-137 Ground Concentration = 6.8E+6 pci/m 2 Time after deposition of sample = 14 days = 1.2E+6 s K t = (1.0E-05 * e -8.1E-7*1.2E6 )+(7.0E-09 * e -2.31E-8*1.2E6 )+1.0E-09 = 3.8E-06 m -1 Calculated Airborne Concentration = (6.8E+6 pci/m 2 ) * (3.8E 6 m 1 ) = 2.6E+1 pci/m 3 Compare to sample results RAAC Update Workshop August

131 Projecting CED (cont.) Nuclide Concentration (pci/m 2 ) DP (mrem per pci/m 3 ) Dose (mrem) * 1 st -year DP = * 2 nd -year DP = Refer to Appendix pg. 26 RAAC Update Workshop August

132 Projecting CED (cont.) DECAY ONLY Nuclide Concentration (pci/m 2 ) DP (mrem per pci/m 2 ) Dose (mrem) Cs E+6 * 1 st -year DP 5.4E-8 = E+6 * 2 nd -year DP 3.2E-10 = RAAC Update Workshop August

133 CED from Inhalation of Resuspended Materials If dose from inhalation of resuspended material is significant (>10% of TED), the CED must be included in your DRL calculations. RAAC Update Workshop August

134 Dose Assessment and DRLs Derived response levels are the gamma exposure rates at 1 meter above the surface that, based on the nuclide mix, equal the relocation PAGs for the first and second years. RAAC Update Workshop August

135 Incident-Specific DRL Incident Specific DRL mr h = Relocation PAG (mrem) Incident Specific DP (mrem per mr h ) Any location having an exposure rate exceeding the DRL (in mr/h) is in the RZ RAAC Update Workshop August

136 Calculating Incident-Specific DRL STEPS: 1. Sample Radionuclide Concentration * DP = Projected Dose 2. Total Projected Dose Calculated Exposure Rate at 1m = Incident Specific DP 3. PAG Incident Specific DP = Incident Specific DRL RAAC Update Workshop August

137 RAAC Update Workshop August

138 Calculating Incident-Specific DRL Example Calculate a first-year incident-specific DRL for the following mix of surface contamination (allow for weathering and decay): Sample Concentrations: I-131: 2.6E+7 pci/m 2 Te-132: 3.4E+6 pci/m 2 I-132: 3.5E+6 pci/m 2 Cs-137: 6.8E+6 pci/m 2 RAAC Update Workshop August

139 Calculating Incident-Specific DRL Example Nuclide Sample Results (pci/m 2 ) Initial Exposure 1 meter (mr/hr per pci/m 2 ) Calculated Exposure Rate (mr/hr) I E+7 x (4.0E-9) = Te E+6 x (2.7E-8) = I E+6 Included w/te Cs E+6 x (6.0E-9) = Total RAAC Update Workshop August

140 Calculating Incident-Specific DRL Example Nuclide Sample Results (pci/m 2 ) DP 1 st Year (mrem per pci/m 2 ) Calculated 1 st Year Dose (mrem) I E+7 x (1.1E-6) = 29 Te E+6 x (2.7E-6) = 9 I E+6 Included w/te Cs E+6 x (4.8E-5) = 326 Total 364 RAAC Update Workshop August

141 Calculating Incident-Specific DRL Example STEPS: 1. Total Dose = 364 mrem mrem mr/hr = 1540 mrem per mr/hr mrem 1540 mrem per mr/hr = 1.3 mr/hr Any area exceeding 1300 R/hr is in the RZ based on the first-year PAG. RAAC Update Workshop August

142 How long will this DRL be useful? RAAC Update Workshop August

143 General Considerations Relocate areas above first-year PAG Prioritize highest exposure rate areas Allow return to areas with background or near background exposure rates Relocate evacuees whose homes are in RZ Gradual return for those outside RZ Evaluate dose reduction effectiveness of simple decontamination techniques and of shielding & occupancy Base recommendations for those just outside of RZ on results RAAC Update Workshop August

144 General Considerations (cont.) Control access to and egress from the RZ Establish monitoring and decontamination stations to support control of the RZ Implement simple decontamination techniques in contaminated areas outside of the RZ Prioritize areas with higher exposure rates Collect data needed to establish long-term radiation protection criteria Decontamination and Shielding & Occupancy RAAC Update Workshop August

145 General Considerations (cont.) Implement simple decontamination techniques in contaminated areas outside of the RZ Prioritize areas with higher exposure rates Collect data needed to establish long-term radiation protection criteria Decontamination and Shielding & Occupancy Clean up and recover contaminated property in the RZ Evaluate food and drinking water RAAC Update Workshop August

146 Likely Dose Reduction Factors Shielding & Occupancy Reduction Factor: The likely dose reduction factor for frame structure shielding is 40% (0.4) The likely average time spent inside the home is 70% (0.7) and the time spent outside the home is 30% (0.3) RAAC Update Workshop August

147 Likely Dose Reduction Factors (cont.) Dose received by people inside their homes: [(0.7) * (0.4)] = 0.28 Dose received by people outside their homes: [(0.3) * (1.0)] = 0.3 ( ) = Shielding & Occupancy Reduction Factor: 0.6 RAAC Update Workshop August

148 Dose Reduction Factor Example If Projected first-year dose is just under 2 rem Shielding & occupancy factor: rem * 0.6 = 1.2 rem Collect data to determine actual reduction factor! RAAC Update Workshop August

149 Simple Decontamination Techniques Change A/C filters Scrub/flush hard surfaces (driveways, roofs) Remove sandbox sand Pay attention to child hygiene Soak or plow soil Remove soil where radioactive materials have concentrated Likely decontamination dose reduction factor: 0.7 RAAC Update Workshop August

150 Dose Reduction Factor Example (cont.) If Original projected dose: 2 rem Shielding and occupancy factor: rem * 0.6 = 1.2 rem Decontamination Factor: rem * 0.7 = 0.84 rem RAAC Update Workshop August

151 Dose Reduction Factors For a nuclear power plant accident, decay and weathering of contamination, along with expected dose reductions from decontamination efforts and shielding & occupancy, make it unlikely that areas below the first-year PAG would exceed the second-year PAG. RAAC Update Workshop August

152 Dose Reduction Factors Use second-year dose projections to determine areas where dose reductions are necessary Only dose reductions already accomplished should be considered when making relocation decisions If determined unlikely that second-year doses in an area can be reduced below the second-year PAG, relocate area during the first year even if below the first-year PAG RAAC Update Workshop August

153 Reentry Temporary entry into RZ under controlled conditions Purposes include: Radiation work Recovery activities Property maintenance and security Factory or utility operation Animal care Retrieving personal items RAAC Update Workshop August

154 Intermediate Phase Dose Guidelines Activity Category Level Emergency Worker Protection Use of Critical Infrastructure Use of Roads and Walkways Access to the Restricted Zone Emergency Worker Public Public Public 5 rem per year 2 rem in first year 2 rem in first year 0.5 rem subsequent years 0.5 rem over one year RAAC Update Workshop August

155 Intermediate Phase Dose Guidelines (cont.) Dose guidelines based on Preliminary Report on Operational Guidelines Developed for Use in Emergency Preparedness and Response to a Radiological Dispersal Device Incident RAAC Update Workshop August

156 Intermediate Phase Dose Guidelines (cont.) Normal occupational limits for radiation workers Guidelines do not override regulations Need not include dose: For living in contaminated area outside RZ From emergency work where the once-in-a-lifetime emergency dose limit is applied RAAC Update Workshop August

157 Intermediate Phase Dose Guidelines (cont.) Include radiation doses received outside the RZ when: Performing monitoring and decontamination functions at decontamination stations Operating access control points RAAC Update Workshop August

158 Late Phase Guidance Begins when cleanup and recovery actions have begun and ends when all recovery actions have been completed May extend for months to years Proceeds independently of intermediate phase protective action activities Aimed at both reducing longer-term exposures and improving interim living conditions RAAC Update Workshop August

159 Late Phase Guidance (cont.) Final cleanup decisions are made and final recovery efforts are implemented Decisions should be made with stakeholder involvement Balance health protection with the desire of the community to resume normal life RAAC Update Workshop August

160 Late Phase Cleanup Steps Characterization and Stabilization Characterization much more detailed and comprehensive Stabilization techniques are designed to immobilize radioactive contamination on soils, buildings, roads and equipment Stabilization reduces chronic low-level exposures to residual radiation, airborne hazards, and volumes of secondary waste RAAC Update Workshop August

161 Late Phase Cleanup Steps (cont.) Goals and Strategies Cleanup goals are informed by the feasibility of cleanup strategies and specific cleanup strategies adjust as experience is gained Balances risk reduction with other societal goals and tolerance for voluntary versus involuntary risk Community involvement and sentiment are vital to this process RAAC Update Workshop August

162 Late Phase Cleanup Steps (cont.) Implementation and Reoccupancy Measurable quantities associated with cleanup goals should be derived Institutional and Engineering Controls Restrictive land uses Restriction on planting vegetable gardens Adding a layer of pavement RAAC Update Workshop August

163 Late Phase Cleanup Steps (cont.) Implementation and Reoccupancy (cont.) Reoccupancy of the affected area will be possible when interim cleanup can reduce short-term exposures to acceptable levels during the time it takes to achieve the long-term goals Large volume waste disposal options Licensed Commercial LLRW Disposal Facilities Solid and Hazardous Waste Landfills DOE Disposal Sites Other Federal Properties RAAC Update Workshop August

164 RAAC Unit 8 FDA Food PAGs & DILs and EPA Drinking Water PAGs & DRLs RAAC Update Workshop August

165 Unit 8 What You Learned DIL Values Recommended DILs Protective Actions Food PAGs and DILs RAAC Update Workshop August

166 DIL Definition The concentration of radionuclides in food that will cause a PAG to be exceeded assuming a defined ingestion period and percent of food contamination. RAAC Update Workshop August

167 Recommended DILs Nuclide DIL Bq/kg pci/kg Sr I Cs Pu Am Ru C C 106 < C C 106 < RAAC Update Workshop August

168 Protective Actions Prior to confirmation of contamination levels Precautionary actions Temporary embargoes justification must be significant Temporary embargoes After confirmation of contamination Normal food processing actions that reduce levels of contamination Condemn if > DILs RAAC Update Workshop August

169 Unit 8 Significant Changes New Drinking Water PAG Drinking Water DRL Values and Calculations RAAC Update Workshop August

170 EPA PAGs for Drinking Water EPA PAGs (2017) For Drinking Water Most sensitive populations General population 1 msv (0.1 rem) 5 msv (0.5 rem) Most sensitive populations include infants, children, pregnant women, and nursing women RAAC Update Workshop August

171 DRL Definition Concentration of a radionuclide in drinking water that will cause a PAG to be exceeded, assuming a defined ingestion period. DRL is the surrogate for the PAG Unlike FDA DILs, if more than one nuclide is present, their dose contributions must be added. RAAC Update Workshop August

172 How to Calculate DRLs DRL = PAG / (Ing a * T * DCF ia ) Ing a = The daily ingestion rate of water for age group a (in L/day) T = The time period that the population is drinking contaminated water (in days). DCF ia =The dose conversion factor (also referred to as dose coefficient) for the ingestion of radionuclide i in drinking water and age group a (in mrem/pci) RAAC Update Workshop August

173 How Were the EPA DRLs Calculated? Calculated for eight different ages (fetus, breastfed infant, infant, 1, 5, 10, 15, and adults) PAGs Dose coefficients Dietary intakes Duration of ingestion (one year at a constant contamination level) Selected the most limiting DRL for each radionuclide for each category (general public and most sensitive populations) RAAC Update Workshop August

174 DRL Considerations EPA allows for incident-specific factors to be taken into consideration including: The particular radionuclides being emitted in this emergency situation The rate and timing of entry of the radionuclides into the drinking water supply, via atmospheric deposition or by other means The rate of natural attenuation of the radionuclides The estimated potential duration of public exposure to contaminated drinking water The estimated daily consumption of contaminated drinking water. RAAC Update Workshop August

175 EPA-Calculated DRLs RAAC Update Workshop August

176 Drinking Water Protective Actions Public Notification Treating Contaminated Water Temporarily Closing Intake Valves Establishing Interconnections to Neighboring Systems Blending Water Sources Importing Water in Tanker Trucks Importing Bottled Water RAAC Update Workshop August

177 Implementation Summary (Food and Water) Sampling and analysis priorities should focus on the primary nuclides that could impact the most sensitive receptors Expansive field sampling and monitoring will be necessary Extensive laboratory analysis will be required Detailed recordkeeping and proper use of chain of custody procedures will be essential RAAC Update Workshop August

178 RAAC Unit 9 RASCAL and Excel for the Intermediate Phase RAAC Update Workshop August

179 Unit 9 What You Learned RASCAL FMDose: Intermediate Phase Application of Excel to Dose Projection RAAC Update Workshop August

180 Application of Excel to Dose Projection RAAC Update Workshop August

181 Unit 9 Significant Changes Updated Excel Spreadsheet (Soil) RAAC Update Workshop August

182 Updated Spreadsheet RAAC Update Workshop August