all the quartz-fiber dosimeters in the rate devices to activate at an early time. Asa result,
they yielded only total initial plus residual exposure data. Station 211.01 was partially blown
out of the ground, The rate device did not drop, thus the station yielded only total initial plus
residual exposure information. The 1-minute drop timers were corroded and did not function.
Consequently, the estimates of residual exposure on Sites Dog and Easy were not accurate.
3.7 SHOT TEWA
Table 3.13 gives Shot Tewa instrumentation and recovery data, and Table 3.14 shows residualexposure data. Data from the Charlie-Dog reef, including scattered initial-gamma data is listed
in Table 3.15.
Total-gamma exposures at Stations 113.03 and 113.09 were well established. Residual-exposure
estimates were obtained from Stations 113.02 and 113.03. These stations were in the same general
TABLE 3.9
SHOT DAKOTA INITIAL EXPOSURE
Shot time was 0606, 26 June 1956.
i
ean
Timing
Fil
Ex oan e
posur
r
Calculated
Estimated
Preshot
Postshot
Residual
Residual
r
r
Initial
Distance
ft
Total
1.17 x 105
1.67 x 10
105
50
1.17 x 10
11.
211.01
Total
Blast
2.48
x 104
4,600
90
50
.
2.47
x 10
213.01
Total
5,175t¢
15
25
§,135
6,605
11.02
211.0
Total
Blast
4,600
,
1,060
65
50
4,485
6,650
12.04
212.0
Total
L minute
880
830
65
50 *
705
7,220
212.03
Blast
5
‘
4,422
5,500
* This result was obtained by subtracting the 1-minute value from the total value.
The other estimates were based on this value.
t This result was obtained by subtracting the total Flathead exposure value of 725 r
-from the Flathead plus Dakota exposure value of 5,900 r.
area and had the same geometry and recovery rates but were in a region where the initial-gamma
exposures were negligible. Film at Stations 113.04, 113.07, and 113.08 read greater than 70,000 r.
The chemical data at 113.04 appeared valid. The chemical data at Station 113.08 was probably in
113.04, and was far below the predicted level. The exposures expected at Station 113.07 were far
above the useful range of the chemical dosimeters andit is probable that they saturated, and that
the actual exposure was much greater than 650,000 r. There was no satisfactory explanation for
the discrepancies that occurred in the chemical data derived from Stations 113.07 and 113.08.
The discrepancies observed in the chemical data from 113.07 and 113.08 suggested that the reliability of the chemical dosimeter systems might have been questionable when they were used in
the environment which existed at Stations 113.04, 113.07, and 113.08. These chemical dosimeters
were exposed to a total gamma dose that was much higherthan their upper range, and they were
probably exposed at a very high dose rate and to a very high neutron flux.
It was felt that the initial-exposure data from 113.03 was reliable since the total exposure was
well established and the residual estimate was valid. Data from Stations 113.03, 113.04, and
113,09 agreed with results from previous events.
eee
nT
LS
error, since it contradicted both the film data at Station 113.08 and the chemical data at Station
35