P. 1 

## PICK-U P DATE : BO X 

## 10 O F 

## 1 0 Step2 : FO RASR C INTERNA

L US E ONL Y (PARTA

_of_ B )

i 1 

## EP ADOCKE TID : 102RQ-R N
41 ) 102RQ-RN-5- 3 43 ) lp2RQr£N-5- 5 45 ) 402RQ-RN-5-7 > 47 ) 102RQ-RN-5- 9 49 ) 102RQ-RN-5-1 1 51 ) 102RQ-RN-5-1 3 53 ) 102RQ-RN-5-1 5 55 ) 102RQ-RN-3- 4 57 ) 59 ) 61 ) 63 ) 65 ) 67 ) 69 ) 71 ) 73 ) 75 ) 77) 79 ) Ste p 3 : FOR ASR C INTERNA LUS E ONL Y CD : OA : / 

## 42 ) 102RQ-RN-5- 4 44 ) 102RQ-RN-5- 6 46 ) 102RQ-RN-5- 8 48 ) 102RQ-RN-5-1 0 50 ) 102RQ-RN-5-1 2 52 ) 102RQ-RN-5-1 4 54 ) 102RQ-RN-5-3 1 56 ) 102RQ-RN-2-5- 1 58 ) 60 ) 62 ) 64 ) 66 ) 68 ) 70 ) 72 ) 74 ) 76 ) 78 ) 80 )

Ste p 1 : FOR ASR

C INTERNA LUS E ONL YX^X Are there more documents fo rthi s Docketi n anothe rbox ? \fE$y Til l ou tContinuatio n Shee tan d go t o Ste p 2 N O

Interna l SFUN D Bo

xNumbe r _35 O F 28 3 Initials/Date : _LD S / 3-8-200 7P. 2



### - v - \

v 

### sfid-xp - #» -s- - 7

Octobe r 3 , 198 6 MEMORANDUM
SUBJECT : APropose dR Q fo r Radium-22 6 i nEquilibriu m Wit hIt s Daughter s TO : Barbar a Hostage , Senio r Projec t Office r

Emergenc yRespons e Divisio n Offic e o f Emergenc yan dRemedia l Respons e FROM : Ala nW . Messing 7*4«3T > Environmenta l Monitoring an dServices , Inc . THRU : Gre g Ricc i

Environmenta l Monitoring an dServices , Inc . Radium-22 6 i s a membe r o f th e uraniu m decayserie s an

di s foun d i nnatur e associate dwit hal l o f th e member s o f thi s series
. Whe nradium-22 6 i s isolate di npur e for mi t will , ove r a perio d o f years , establis hequilibriu mwit hit s daughters
. Radium-22 6 an

d it s daughter s ar e show ni nTabl e 1 along wit h thei r half-live s an dpropose dRQs
. Afte r equilibriu

mi s established , th e quantit yi ncurie s o f eac ho f th e daughter s wil l b e equa l t o th e quantit yi ncurie s o f th e origina l radium-22 6 presen t . Fo r example , i f on e curi e o f radium-22 6 i s allowe d t o come t o equilibrium , on e curi e o f eac h o f th e daughter s wil l hav e bee nforme d (assuming n o los s o f gaseou s radon-222) , an d on e curi e o f radium-22 6 wil l remain
. Applicatio no f th e mixtur e rul e require s tha t a repor t b e mad e t o th e Nationa l Respons e Cente r whe nth e su mo f th e curie s o f eac hradionuclid e release d(Q. ) divide db yth e R Q fo r th e

Thi s i s strictl ytru e onl yi f th e half-lif e o f th e paren t i s infinite
. Fo r radium-22 6 i t i s a goo dapproximation
.- 1 P. 3

TABL E 1

RADIDM-22 6 AN

DIT S DAUGHTER S

Radionuclid e

Radium-22 6 Radon-22 2 Polonium-21 8 Lead-21 4 Astatine-21 8 Bismuth-21 4 Polonium-21 4 Thallium-21 0 Lead-21 0 Bismuth-21 0 Polonium-21 0 Thallium-20 6 Half-Lif e

160 0 y r 3.82 3 day 3.0 5 mi n 26. 8 mi n 2 se c 19. 7 mi n 0.00016 4 se c 1. 3 mi n 2 1 y r 5.0 1 day 138. 4 day 4.1 9 mi n Propose d R Q (Ci )

1 10 0 1 1 1 1 1 1 0. 1 1 0 0. 1 1P. 4

radionuclid e (RQ. ) i s equa l t o o r greate r tha none . Th e minimu m releas e requiring a repor t i s foun dwhe nth e following equalit y i s satisfied :

£ [(Qi)/(RQi) ] = 1

Fo r a releas e o f radium-22 6 i nequilibriu mwit hit s daughters , wher e eac hradionuclid e i s presen t a t a leve l o f on e curie , th e su

mo f (QJ)/(RQJ ) i s equa l t o 28.11 , a s calculate d below
. (1/1)*(8 ) + (1/100 ) + (1/10 ) + (1/0.1)*(2 ) = 28.1 1 Eigh t radionuclide s i nTabl e 1 hav e RQ s o f 1 curie , on e ha s a nR Q o f 10 0 curie , on e ha s a nR Q o f 1 0 curie , an d2 hav e RQ s o f 0. 1 curie
. Clearl ya releas e o f thi s siz e woul drequir e a repor t t o th e Nationa l Respons e Center
. Th e minimu m releas e necessitatin g a repor t i s 1/28.11 , o r a releas e containing 0.035 6 curi e o f eac hradionuclide
. Becaus e ther e ar e 1 2 radionuclide s involved , th e tota l activit yo f th e releas e o f radium-22 6 i n equilibriu

m wit hit s daughter s necessaryt o satisf yth e equalit y abov e i s 1 2 time s 0.035 6 o r 0.4 3 curie
.
Base d o nth e mixtur e rule , a releas e o f 0.4 3 curi e o f radium-22 6 i nequilibriu mwit hit s daughter s wil l requir e a repor t t o th e Nationa l Respons e Center
.