RADIOACTIVITY AS RISK COMPONENT
AT URBAN CONTAMINATED SITES
– A MULTIDISCIPLINARY CHALLENGE
Rainer Gellermann1
Imke Goebel-Stadler2
Ilka Grundmann2,
Kristin Nickstadt1
1
Fugro Consult GmbH
Daimlerstraße 18
D-38112 Braunschweig
[email protected]
2 Landeshauptstadt Hannover
Boden- und Grundwasserschutz
Prinzenstraße 4
30159 Hannover
[email protected]
www.fugro-hgn.de
Preface
The following presentation tries to
summarise some practical experience in the
field of risk communication gained during
dealing with specific cases of contaminated
ground in Hanover since 2008. It has to be
mentioned that the authors of this
presentation were neither the first nor the
only persons, who were involved in the risk
communication in this specific case. Very
important parts of communication were
performed by P. Günther (IfUA Bielefeld)
and representatives of the administration of
the Hanover Region, in particular A. Priebs.
Nevertheless, we believe that our personal
experience allows us to derive some insights
and conclusions that may be useful for
others, too.
2
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Background: History
ƒ 1862: Foundation of the „Chemical
Plant E. De Haen“ in the village List
near Hanover.
ƒ 1865-68: At the site of the current
contaminated ground a larger plant was
built. Production of inorganic chemicals.
ƒ 1902: Company moved to Seelze near
Hanover.
ƒ Residues (heaps) were transferred to a
site northward (now: „Lister Damm“)
and disposed of. The disposal site was
later developed to an allotment area.
ƒ 2008: Discovery of radioactive
contaminations in the residential area
around the “De-Haen-Platz” in HanoverList.
3
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Situation in 2008 (*)
Ambient radiation: up to 15000 nSv/h (background 80 nSv/h)
Chemical contamination (soil) : As, Pb, Sb, Hg / Cd, …
Radiological contamination (soil): Th-230; Ra-226, U-238, Th-232
4
(*) Contaminated sites on ground owned by City
of Hanover
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Situation in 2010/11
Both sites decontaminated (“partial remediation”).
Ambient radiation: Lower than 500 nSv/h (background 80 nSv/h)
5
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Experience - 1
Caused by the lack of specific regulations concerning radioactive legacy
sites, radioactive contamination had to be assessed according to the
rules of the German Soil Protection Act.
– Radioactivity can be considered as carcinogenic substance (like
arsenic, too).
– Threshold levels can be derived based on the conceptual approaches
of the German Soil Protection Ordinance (hazard level 5.10-5).
– Remediation measures need specific justification.
– Excavated materials are residues according to the German Radiation
Protection Ordinance. Disposal requires release from regulatory
control – and acceptance of radioactivity by disposal companies.
Æ Conclusion: Soil protection has been proved as feasible basis for
decision making, but several interfaces to radiation protection have to
be taken into account.
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Experience - 2
The term “radioactivity” leads to a great deal of uncertainty amongst all
involved or affected persons.
- Soil protection authorities have been confronted with new kind of
problems.
- Citizen claimed information and action.
- Political bodies claimed information and participation in decision
making.
- The fear of radiation was used to justify claims related to individual
interests – and had to be dealt with.
- Media were highly interested and required factual information.
Æ Conclusion: Active communication about risks is of crucial
importance.
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Experience - 3
The communication on risks results in confusion, if the hazards related to
police and public order law and the risks due to soil contamination
assessed with criteria of soil protection are not carefully separated.
– In our case the situation was significantly below the range of acute
hazards, which would have had to be assessed as an radiological
emergency situation. But actions were considered to be justified and
necessary(!) according to soil protection standards if chronical
exposures of carcinogenic substances may exceed the hazard level
5.10-5 lifetime risk.
– The contaminated part in the park area was immediately fenced and
remediation planning was started independently from the final hazard
assessment.
Æ Conclusion: One possibility to resolve contradictory viewpoints is to
be proactive in a way that anticipates obvious requirements.
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Experience - 4
To find out suitable and appropriate remediation measures requires
communication about aims and targets of planned actions. One aspect to
be considered is the judgment of sustainability vs. remaining risks.
– Contaminated sites are existing situations that cannot be judged with
criteria of precautionary environmental protection.
– The conscious dealing with remaining risks can be part of sustainable
solutions. This includes to accept aftercare measures.
– All decisions should be based on clear knowledge that the system of
values that is used for the assessment of radioactive soil
contaminations may change over longer periods.
Æ Conclusion: Best solutions are those to which the most involved
parties can agree with.
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Experience - 5
ƒ The involvement of affected people is of great importance. Factual
information about the actual risks is necessary but not sufficient.
– Radioactivity is perceived as a very special danger. Concerned
people must be taken seriously, also if their concern seems
causeless.
– Remediation workers have usually no personal experience with
radioactivity. But they accept radiation as “common” risk component
(like other toxic substances), if it is clearly communicated as part of
occupational safety.
– Communication about radiation needs both: rational and emotional
arguments.
Æ Conclusion: Communication needs teamwork of different
representatives: external experts and authorities, men and women,
persons in charge and members of their staff.
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Thank you for attention
Danke für Ihre Aufmerksamkeit
Contact / Ansprechpartner:
Dr. Rainer Gellermann
Mail: [email protected]
Phone: 0531 213699-10 / Mobile: 0176 12622727
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