12
Activities of the Tritium/C14 Working Group Phil Davis, AECL, Working Group Leader Mikhail Balonov, IAEA Scientific Secretary Ian Barraclough, Enviros, Technical Secretary
Act
iviti
es o
f the
Trit
ium
/C14
W
orki
ng G
roup
Phil D
avis,
AEC
L, W
orkin
g Gr
oup
Lead
erMi
khail
Balo
nov,
IAEA
Scie
ntifi
c Sec
reta
ryIan
Bar
raclo
ugh,
Env
iros,
Tech
nica
l Sec
reta
ry
Pg 2
Obj
ectiv
es o
f the
WG
•To
esta
blish
the c
onfid
ence
in th
e pre
dict
ions
of
envir
onm
enta
l trit
ium
and
C-14
mod
els, p
artic
ular
ly m
odels
for t
he fo
rmat
ion
and
trans
loca
tion
of o
rgan
ically
bo
und
tritiu
m (O
BT)
•To
reco
mm
end
mod
ellin
g ap
proa
ches
that
will
resu
lt in
im
prov
ed p
redi
ctio
ns•
To en
cour
age e
xper
imen
tal w
ork t
hat w
ill lea
d to
dat
a set
s th
at ca
n be
use
d in
mod
el te
stin
g
Pg 3
Test
Sce
nario
s
Com
plet
e−
Perc
h La
ke sc
enar
io−
Soyb
ean
scen
ario
−Pi
cker
ing
scen
ario
Ongo
ing
−Hy
poth
etica
l sce
nario
s−
Pine
tree
scen
ario
−Ri
ce sc
enar
io (C
-14)
−Mu
ssel
scen
ario
−Na
ture
and
defin
ition
of O
BTIn
Pre
para
tion
−An
imal
scen
ario
s
Pg 4
Perc
h La
ke S
cena
rioA
test
of m
odels
that
pre
dict
triti
um co
ncen
tratio
ns in
aqua
ticec
osys
tem
s at s
tead
y sta
te
Pred
icted
HTO
conc
entra
tions
ge
nera
lly la
y with
in 30
% o
f the
ob
serv
atio
ns
Pred
icted
OBT
conc
entra
tions
gene
rally
lay w
ith a
fact
or o
f 2of
the o
bser
vatio
ns
The f
inal
repo
rt is
com
plet
e and
will
be p
ublis
hed
shor
tly
Pg 5
Soyb
ean
Scen
ario
A te
st o
f mod
els th
at p
redi
ct th
e tim
e-de
pend
ent b
ehav
iour
of t
ritiu
min
plan
ts ac
utely
expo
sed
to el
evat
ed le
vels
of H
TO in
air
The m
odels
gen
erat
e a
signi
fican
tly sm
aller
amou
ntof
OBT
per
uni
t tim
e-in
tegr
ated
HTO
conc
entra
tion
than
the
plan
ts p
rodu
ce in
reali
ty
A dr
aft f
inal
repo
rt ha
s bee
n pr
oduc
ed an
d wi
ll be f
inali
zed
this
week
Pg 6
Pick
erin
g Sc
enar
ioA
test
of m
odels
that
pre
dict
triti
um co
ncen
tratio
ns in
agric
ultu
ral
ecos
yste
ms a
t ste
ady s
tate
The m
odels
per
form
ed w
ell fo
rHT
O co
ncen
tratio
ns in
soil,
milk
and
beef
, and
for O
BT in
milk
The m
odels
ove
rpre
dict
ed O
BT
conc
entra
tions
in p
lants
and
HTO
and
OBTc
once
ntra
tions
in eg
gs
and
chick
en fl
esh
A dr
aft f
inal
repo
rt ha
s bee
n pr
oduc
ed an
d wi
ll be f
inali
zed
this
week
Pg 7
Hyp
othe
tical
Sce
nario
sTo
asse
ss th
e con
sequ
ence
s of a
n ac
ute a
tmos
pher
ic re
lease
of
tritiu
m w
ith th
e aim
of p
rovid
ing
guid
ance
to d
ecisi
on-m
aker
s in
man
agin
g th
e acc
iden
t
Larg
e diff
eren
ces i
n pr
edict
ed ai
rco
ncen
tratio
ns w
ere r
educ
ed b
y de
finin
g th
e sce
nario
mor
epr
ecise
ly
The m
odels
pre
dict
very
diff
eren
tco
ntrib
utio
ns to
tota
l dos
e by t
hedi
ffere
nt ex
posu
re p
athw
ays
The l
ates
t res
ults
will
be d
iscus
sed
this
week
to tr
y to
expl
ainth
ese
diffe
renc
es
Food
- Ca
se 1
dos
es v
ersu
s pa
thwa
ys -
norm
alize
d
0
100
200
300
400
Kore
aG
erm
any
Japa
n - Y
Japa
n - K
Cana
daRo
man
iaIn
diaFr
ance
mSv
Milk
Mea
tCe
real
sG
arde
n ve
gIn
halat
ion
Pg 8
Pine
Tre
e Sc
enar
ioA
test
of m
odels
that
pre
dict
triti
um co
ncen
tratio
ns in
nee
dles
and
tree r
ings
for t
rees
gro
wing
nea
r a co
ntin
uous
atm
osph
eric
sour
ceof
HTO
The i
nitia
l pre
dict
ions
of H
TO
conc
entra
tions
in p
ine n
eedl
essc
atte
red
arou
nd th
e obs
erva
tions
The s
cena
rio w
as re
vised
toin
clude
a m
ore d
etail
ed g
roun
d-wa
ter c
ompo
nent
The l
ates
t res
ults
will
be d
iscus
sed
this
week
and
reas
ons f
ordi
ffere
nces
in p
redi
ctio
ns w
ill be
soug
ht
Pg 9
Ric
e Sc
enar
io (C
-14)
A te
st o
f mod
els th
at p
redi
ct st
eady
-sta
te C
-14 c
once
ntra
tions
inpl
ants
gro
wing
nea
r a co
ntin
uous
atm
osph
eric
sour
ce o
f C-1
4
The s
cena
rio d
escr
iptio
n wa
s di
strib
uted
dur
ing
the s
umm
eran
d th
e firs
t rou
nd o
f calc
ulat
ions
has b
een
subm
itted
The r
esul
ts w
ill be
disc
usse
d at
this
mee
ting
Pg 1
0
Mus
sel S
cena
rioA
test
of m
odels
that
pre
dict
the t
ime-
depe
nden
t beh
avio
ur o
ftri
tium
in aq
uatic
org
anism
s exp
osed
to an
abru
pt ch
ange
intri
tium
conc
entra
tions
in th
eir en
viron
men
t
The s
cena
rio d
escr
iptio
n wa
s di
strib
uted
dur
ing
the s
umm
eran
d th
e firs
t rou
nd o
f calc
ulat
ions
has b
een
subm
itted
The r
esul
ts w
ill be
disc
usse
d at
this
mee
ting
Pg 1
1
Scen
ario
s In
volv
ing
Larg
e A
nim
als
Scen
ario
s are
still
in th
e plan
ning
stag
e. A
num
ber o
f dat
a set
s ar
e bein
g co
nsid
ered
invo
lving
shor
t-ter
m o
r pro
long
ed ex
posu
reof
cows
or p
igs t
hrou
gh th
eir d
iet.
The s
cena
rios w
ill te
st d
ynam
icm
odels
of H
TO an
d OB
T be
havio
urin
larg
e ani
mals
A te
st sc
enar
io in
volvi
ng la
rge
anim
als w
ill be
adop
ted
at th
ism
eetin
g
Pg 1
2
Nat
ure
and
Def
initi
on o
f OB
T•
The O
BT o
f int
eres
t fro
m a
dose
poi
nt o
f view
is ca
rbon
-bou
nd
tritiu
m•
In p
ract
ice, O
BT co
ncen
tratio
ns ar
e det
erm
ined
expe
rimen
tally
as
the a
ctivi
ty o
f non
-exc
hang
eabl
e trit
ium
in th
e com
bust
ion
wate
r of t
he d
ried
sam
ple i
n qu
estio
n•
Som
e of t
he n
on-e
xcha
ngea
ble t
ritiu
m in
the c
ombu
stio
n wa
ter
may
not
be c
arbo
n bo
und,
but
asso
ciate
d wi
th la
rge m
olec
ules
th
at re
main
afte
r the
exch
ange
able
tritiu
m is
rem
oved
(bur
ied
tritiu
m)
•Bu
ried
tritiu
m is
imm
ediat
ely re
lease
d as
HTO
dur
ing
dige
stio
n an
d do
es n
ot h
ave t
he d
ose c
onse
quen
ces o
f OBT
•Ex
perim
ents
inve
stig
atin
g th
e exis
tenc
e of b
uried
triti
um ar
e go
ing
on in
two
mem
ber l
abs
