Environmental Monitoring Presented on behalf Lutz Moritz (TRIUMF) by

Transcription

1 Environmental Monitoring Presented on behalf Lutz Moritz (TRIUMF) by Kamran Vaziri Ph.D. Radiation Physicist III Fermi National Accelerator Laboratory 1

2 2

3 ! "# $ %!!! &!'$ 3

4 ! (!!$ )!*!'! "#!!!!!''!!!&!'$ 4

5 +, QA involves all those planned and systematic actions necessary to provide adequate confidence that a facility will perform satisfactorily and safely in service.! - '!&!$ - *.'* ' '!+&, 5

6 -!('!+, - ' - / *!/!* +0123,$ 6

7 -!!* - -! 4! '!'!!!$ 7

8 Environmental Monitoring Elements %!5 - * -! '$ %! $ -!* $ -!!*'$!! '!3'$ 8

9 Environmental Monitoring Planning %!!!5!. *' - '!* - * -!!$!* '$!!!$ 9

10 '6 7.5!!!'* 8!.+$$*,! +$$**3 *),* 7!(!!!*' '$ 10

11 '6 '! ** * * 7!( $ 11

12 Standards, Limits and Guidance %!2!7! +9,7! 2:;11$:917<=:5 %! ,2'' $ &91!!2 '!'.2$ 12

13 Standards, Limits and Guidance.!.! * * * $ ' >? ';17@9 'A+)A,$ %!' & $ 13

14 Environmental Monitoring Program %! $ 9/!"#$ -!! ' -!! $ B/!!' 14

15 Types of Sources ' 5 '!! - ' - 15

16 !!+*γ*µ,$ %!!!''.$ %!'!!!!!/ $ $ 16

17 Fermilab Example- MERL ' 3'+3,. *γ/! $?.! '$ 17

18 Fermilab Example- MERL 18

19 MERL- Neutrons Detector For neutron detection, the MERL has a DePangher long counter. For measurements of neutron spectra outside the shields use a set of Bonner spheres. 19

20 MERL- Muons and Charged Particles!+!,*! 3!!!!$ Muon Telescope A telemetry system relays information on beam parameters to the MERL. A 3 x 3 NaI (Tl) scintillator is used with a multichannel analyzer to detect gamma rays. 20

21 Supplement to MERL %!''* &+CA*D C7!D C D, '$ %!! $ γ/ '!'$ 21

22 ::$!' $ 2! γ/$! '$ A 22

23 Chipmunk A stationary rad. Monitor (developed at Fermilab) TE ion chamber (n,γ,cp) Stable indoors & outdoors Used both beam-on and beam-off About 250 installed on site 23

24 Another Example of Real-time Site Monitoring A network of prompt radiation monitoring stations around the JLab boundary. 24

25 Monitoring Program 2! - - $ &!!!!! '!'/!'! $ 25

26 Environmental Monitoring Program %!5!. *!!!! *!!!'.'$ 26

27 ! Prompt Fields - ) -2 - /! // &!! '! '$ 27

28 '$ %!' -!! -) ;1 E** - 9=0 7 -!/!$ Transient offsite sources. 28

29 /! Argon Ion Chamber!?23*! '$!/! $ 29

30 /!*! Passive: TLDs with or without Bonner Spheres Active: Long counter Snoopy or WENDI Bonner Spheres with LiI(Eu), 3 He or BF 3, detectors 30

31 Prompt Radiation Fields- neutrons %!''CD $!!! &!!!'' &$%!!C'D!( $ 3 '+γ B$B8,*!!!$ &!* &!! $ 31

32 / %!4!' :15 -!F - 3!!!6' - G5%!B1/=18!F -?911/91118!!F - +'&H, 32

33 Prompt radiation fields- neutrons /!'!'! 3!!$!!! '!'$ 33

34 /!!!!!!!!!!! $ 34

35 /! for r greater than about 20 meters: aq ( r Φ ( r) = 1 e ) e 2 4π r / µ r / λ a = 2.8 an empirical buildup factor, µ is the corresponding buildup relaxation length (56 meters) λ is the effective interaction length (meters). Φ (r) the fluence (1/m 2 ) Q is the number of neutrons emitted by the source (1/m 2 ). 35

36 /! Normalized Value of r 2 φ(r) r (meters) Estimate the value of λ from the neutron energy spectrum information 36

37 /! & r 2 φ(r) (n/10 12 p) r (meters) 37

38 / 38

39 / 39

40 / 40

41 /2! ' 41

42 %!/! - $ * - &!* - - $ $ ' &$ 42

43 !+'$ /', )/ ' 43

44 27I+µ7> =,G' G I :> 1$9> 3 7 ;1!> 9@<!> = A B1$1 1$9 ) 0 4 <$1 1$1; J 99 7 B11$1 9$1 2 9= ) ;9$1 1$1B ) 9: B0$1 1$1B ) BB ) 1$= 1$119 2 ;9 ;0$1 1$19 ) :; 1$= 1$11B 7 1$10 ;&91 /; J B=<? B&91 /: 9&91 /0 J 44

45 I!!/+ 9: * 9= )* 99 7, ;9 $ ' &$ 7!' '' AI $ 45

46 +*/'!,!$ %!! 0 4*!' $ '!!!+$$!!$,!A%'.' ''''!!! = A.!.$ 46

47 '!!*'!/ ' '! &$ %!"'#!! $'!!!$ '!/ 7!'$ 47

48 &!! &!!&!! &!$ ' $ 48

49 49

50 ) A' 50

51 7 Electrical Connector Quick Removal Fasteners Stainless Steel Inlet/outlet Lead Shield GM Detector Aluminum Case 51

52 I/ ) I +8, G! G! +4. /=,L9; =< 7 9@;B 9 1$; B9@< 9$B 1$B 9$B 1$B =K 7 B:1$= 1$< 1$: 9B@0 1$K 1$= 9:90 1$K 1$= 1$K 1$B ;9 9BK; <$ 1$; <$1 1$; 52

53 /7!/ Data Counts Fit Time (seconds) 53

54 Iβ/2 ) β +8, ε )+I, +>B, ) +4., 9= ) ;KB β N :$=M B=$= B9<$ =<@ β N ;$;M 9@$: 9<K$: ;9 ;@; β / :$;M 9: 0=: β N 0$9M B$: 90$; Proton & heavy ion accelerators versus electron accelerators 54

55 '% Bubblers flowmeter pump 55

56 7'% Make sure beam conditions are stable Connect triple-bubbler to stack Set flow rate Start pull through pump Run for a set time Measure concentration of tritium Record beam parameters for the run 56

57 7'% Volume of air used= flow rate x time HTO activity= sum( bubbler liquid x HTO concentration) Calibration factor HTO Concentration in stack air = HTO activity / Volume of air used Notes:» May need catalyst to convert HT, T2 to HTO upstream.» Environmental issues of tritium sorption and desorption:» Beam on releases» Beam off releases 57

58 !27 7<<-7 +, I. $ '!* $ '! '/$?5* $ <1+:1,$!& 58

59 7'!2 +!/ ;9,!&$ 7'! /(!'$ ).!!/$ 59

60 G G!'! 5 9$ )/GO **!! $ B$.O!!.$ '!.=:;1 '!$ 60

61 G 7/3/!/ *'' ' &$ 24/! '$!('/ $ 3!' 61

62 !* $ ) +%,!! $ *! ''! '!AI.!.$ 62

63 DCG for / Radionuclides in Water 27I+7>, A/ G I A/= 9B$=P;:1@ B*111 B1QQ 4/0 :=$= 9*111 ;1 )/BB B$@ PK;K 91 1$; 7/;: 9@: :1 B /:; =9B :1 B 7/:0 B ; 7/:< 09$= ;1 9$@ 7/@1 :$B0 P9KB; : 1$B 7/9=0 =1 = 1$9B /9K: 9<= 911 ;?/B=< ;$;0&91 K 1$1@ B$;&91 /= 63

64 &/* 64

65 /& 65

66 -%!!!!!! / 2'!!!!'+, $ 66

67 '! /'*!!/ AI $!!!.' '!AI$ &'! =B * =: =@ 7$ 67

68 2!β/!!+!! /,$ 7!!!/ / '$ %!.'!'!!.' $ 68

69 I & Beam 69

70 The Propagation of Radionuclides Through Geological Media: Concentration Model N p = # of protons S ave = average stars/cm3 K i = Σ production ratio L i = leaching fraction ρ = soil density W i = water fraction 99% leaching t irrad = irradiation time t c = cooling time τ i = mean life time of isotope N KLS C 1 exp( t / τ) exp( t / τ) w = p i i ave { } i irrad i c i ρ i 70

71 %!%!! I Fraction leached Weight of water (as a fraction of soil weight) 71

72 %!%!! I 72

73 The Propagation of Radionuclides Through Geological Media D x 2 x C 2 ν x C x λc = C t D x is 1D dispersion coefficient ν x is the seepage velocity λ is the decay constant C is the concentration 73

74 %!%!! I!2#3 v = K p dh dx! $ %!!!!$ E!.!! $ 74

75 I 75

76 % MuCool Tritium (10 yr Pulse) H3 Concentration Ratio(7m) H3 Concentration Ratio(7.5m) H3 Concentration Ratio(8m) H3 Concentration Ratio(8.5m) H3 Concentration Ratio Years 76

77 ' $! $ )! (!'+CAD,!'!!'$ %!' &'$ $ $ 77

78 !+$$ = A$ 0 4* B; )* BB )*/,!!!!!$ 4' - $ - (*!*!74$ 78

79 %!! - * - * - *! $ %! -!'* '!/$ 79

80 7 '!!*/ - ' -!.' - 80

81 Acknowledgements Adapted from manuscript prepared by Lutz Moritz (TRIUMF) Helpful comments & text material received from Don Cossairt (Fermilab) Support was provided by Mr. William Griffing, Fermilab ES&H Director, who encouraged my participation 81