Civil Engineering Reference
In-Depth Information
0.5 Sv. On the whole, 135,000 persons were evacuated over the first few days
[
5
]. As a result of varying weather conditions, radioactivity was carried as far as
Germany (Chap.
4
) and other countries in Western Europe, including Scandinavia.
9.2.2 Chernobyl Accident Management
Hundreds of specialists and approximately 800,000 military men were involved in
pushing back the fuel elements into the reactor in “shortest-time activities,” piling
up sand, lead, boron carbide, and concrete, building a provisional concrete shield,
and decontaminating plant compartments. The maximum radiation exposure of
these members of emergency teams had been set at 350 mSv [
5
-
9
] (see also
Chap.
4
).
Approximately from 2012 on, the destroyed reactor unit 4 is being enclosed in a
new arched sarcophagus [
10
,
11
].
9.2.3 Contaminated Land
As a result of the prevailing weather conditions with precipitation, a number of
areas in Ukraine, Belarus and in the western part of Russia were very highly
contaminated over the first 10 days. While iodine-131, with a halflife of 8 days,
had decayed already after roughly 1 month, cesium-134 (halflife 2 years) for the
first 10 years or so and, above all, cesium-137 (halflife roughly 30 years) over
approximately 100 years will determine the radiation exposure of the population
due to ground-borne exposure and food ingestion [
4
,
5
]. The regions with the
highest exposure levels are shown in Figs.
9.5
and
9.6
.
Depositions in excess of 40 kBq/m
2
cover large areas in northern Ukraine and
southern Belarus. The most highly contaminated zone in Ukraine is the 30-km zone
around the RBMK-1000 reactor of Chernobyl with more than 1,500 kBq/m
2
.
In the region of Bryansk, Belarus, the highest soil contamination in some
villages was measured to be up to 5,000 kBq/m
2
. In the Kaluga-Tula-Orel region,
contamination of 600 kBq/m
2
was found.
In summary, 3,000 km
2
were contaminated with
more than
1,500 kBq/m
2
of
Cs-137,
1
roughly 7,200 km
2
with 600-1,500 kBq/m
2
of Cs-137, and roughly
103,000 km
2
with 40-200 kBq/m
2
of Cs-137.
Dose exposures for people living in these areas can be estimated from similar
dates given in Sect.
9.3.4
for the Fukushima reactor accident.
1
No upper limit or higher level ranges as in case of Fukushima (Sect.
9.3.4
) were published for
Chernobyl.
