3,000
Table t
Excess radon
.
aw
H4 2,000 +
cay Of tadon
4
Liquid
tquid
id
rem
emove
,
.
Decay of RaA
3
x
S 1,000;
T
0
—
|at30 days)
Spas
*Vichy Celestin
Juventus
*Vichy Catalan
48-5
45°5
43-3
—
—
—
3,150
1,250
1,700
16:4
36-4
25-5
Llandrindod
26-2
.
*Perrier
10
20
30
Hours after sealing liquid sample
. 40
Penzance
Penzance
thorium series, such as thorium-228 (radiothorium-
228), at comparable levels of activity, the initial
thorium series activity of these waters is regarded as
due to radium-224 and its daughters. These values
are given in Table 3 corrected for decay ofactivity
since time of sampling.
In a numberof the waters having very low activity
it has not been possible to determine either the level
of radium-224 or of the lIong-lived members of the
thorium series.
In a few specimens having intermediate values of
long-lived «-aetivity, the presence of thorium-228
and its daughters has been observed but at levels
representing small fractions of the total long-lived
a-activities given in Table I.
Results
The values of long-lived a-activity together with
the activities due to excess radon-222 and its daughters are given in Table 1 for various categories of
water.
In a number of instances waters from more than
one source have been measured for a given town, and
these are listed separately. Ground-waters have been
divided into two groups comprising those derived
from boreholes in chalk and those from boreholes in
other geological strata.
Surface waters include
sources such as springs, rivers, lakes and reservoirs.
Column 4 of Table 1 gives the content of solid
matter observed (in parts per million), and column 5
the long-lived «-activity of this residue 30 days after
evaporation of the liquid specimen.
Table 2 indicates the range of values and mean
long-lived «-activity for the different categories of
water and their residues.
In Table 3 the total a-activity of a number of the
more active samples is broken down into its three
main components.
Discussion
It will be seen from Tables | and 2 that the highest
values of long-lived a-activity are found in the group
of spa waters, which possess high contents of mineral
matter having specific activities greater than those
2
1
St. Ives
Fig. 3
in a numberof our specimens is due to the presence
of radium-224 and its daughters in the freshly sampled
waters. In the absence of long-lived members of the
1
3
2
1
1,000-2,000
16°7
200-300
Penzance
Camborne
Camborne
3
1
2
1
200-300
4:5
2:2
1,500—2,0U0
—_
2,540
3,320
10,200
(uue./gm.
14-7
7-9
1-7
—
210
675
370
21°5
3-3
9-40
4-10
2:20
1:41
9,000-10,000
600
100-200
1,000-2,000
163
170
125
83
57-6
24:1
17-6
17-0
1-00
9,000~10,000
42
1:24
1:02
2
sampling)
37-0
1:8
St.ives
Helston
Helston
Helston
sans
of residue
million)
Buxton
*Vittel
+
_
a-Activity
(parts per
Cornish waters
0
Solid
matter
observed
at time of
Bath
Decay of RaB+RaC
(4zc./litre
{uuc./litre
Leamington
/
“tt
a-activity
at30days)|
&
me
33
Long-lived and daughters;
Origin
700-800
160-200
0-90
0-59
0-46
500-600
4,000—5,000
4,000—5 000
54
7
133
33
3
4-8
23-0
14-6
23-8
6-8
7-1
92-0
*
Ground-watcrs
(not chalk
strata)
Bristol
1
Wolverhampton:
Bristol
2
Leamington
Spalding
Hartlepools
Ashford
(Kent)
Cirencester
2
South Staffs 1
Ground-waters
(chalk strata)
London
1
Uxbridge
Canterbury
Sutton
(Surrey)
Ashford.
(Kent)
Portsmouth
Colne Vailey
Amersham
i
Barnet
2-90
300-400
1,230
24
2°28
1:75
—_—
600-700
73
300
8-4
5-8
1:34
$-00
100-200
100-200
360
38U
3:7
2-6
0-58
0°33
~ 10
—_—
210
zou
133
2-8
1-22
0°65
0:30
—
—
—_
380
216
234
3°2
3-0
1:3
0-27
10-20
100
2:7
0-26
_—
200
1-60
O-3F
1 0-23
0-22
0-22
-
—
100-200
—
420
3:8
2:8
1-3
1:3
209
360
217
1-1
0-5
i-d
100-200
200
0-11
0-11
—_
—_
125
188
a9
0-6
1
4
3
2
0:81
0-62
0:52
0:47
0-41
100-200
300-400
50-100
—
—_
370
240
158
380
284
244
30
25
2:2
2°6
3:3
1:2
1:5
1-4
13:1
12-0
Festiniog
Skipton
Aberdeen
Manchester 1
Charminster
Dundee
Torquay
Edinburgh
Aberystwyth
Glasgow
Glamorgan 2
0-20
0-20
0:14
0-12
0-11
0-11
0:11
0:10
0:10
0-09
0-09
—_—
<i
—_
—
—
<i
<l
<i
—
—
—
_
380
42
54
96
33
55
33
—_
—
33
_
2-5
3:3
2-2
1-2
3°'3
2-0
3-0
—_
_
2-7
South Staffs 2
0-08
—
208
_
—_—
33
29
0-03
—
—_
—
—_
—
5
_
21
30
—_
—_
0-03
—_
_
_—
Farnham
Common
Brighton
Surface waters
Bristol
Glamorgan
Bristol
London
London
Bath
Belfast
Paignton
Blaenau
Sheffield
Hamilton
Birmingham
Manchester 2
Argyit
Flan Valley
Caernarvon
Manchester 3
Dolgelley
Bangor
Betws-yCoed
Hazleton
0-19
100-200
0-33
0°38
Q-30
0-09
10-20
—_—
_
—_
0-08
<i
0-05
<1
0-07
0-05
0-04
0-04
0-04
0:08
0-02
_
54
1:7
0:4
38
21
15
3:3
_
* Bottled specimens as purchased
1:0
2-1
1-7
3-0
_—
1:9
1-0
—