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Remedial measures are necessary for the
contaminated Greenland fjords in Norway.
A life cycle assessment of different reme-
dial options shows that it is possible to help
both the fjord and the climate at the same
time, says Magnus Sparrevik in his PhD. Con-
taminated sediments and industrial waste
is a problem in more than 120 Norwegian
harbor and fjord areas. In 24 of them the
situation is so serious that fish and shell-
fish should not be consumed too often. It is
therefore a need for remedial action in these
areas. In his PhD Magnus Sparrevik however
comes with an important advice: - We have
to make sure that environmental protection
is not causing larger problems than it solves,
he says.
By adding marine clay mixed with activated
carbon to the seabed of the contaminated
Grenland fjords it is possible to reduce the
stream of dioxines from the sediments to
the ecosystem with up to 90%. The reason is
that activated carbon has a huge active sur-
face with potential to bind large amounts of
contaminants. When Sparrevik conducted a
life cycle assessment (LCA) on the remedial
operation he discovered that the origin of
the activated carbon is very important for
the total environmental impact. Activated
carbon coming from coal mines in China and
carbon coming from coconut shell waste in
India had the same sorption capacity and
therefore the same ability to bind contami-
nants. However, they behaved quite differ-
ent in a life cycle perspective.
Beneficial use
– If the capping is conducted with carbon
from Chinese coal, the global environmental
cost of extraction will abolish the environ-
mental benefit in Norway. But, if the capping
is made with biochar from India the total
environmental account will be much more
positive, says Sparrevik.
– Then the capping will both create a better
local environment and contribute to a better
climate, he continues.
The reason is that activated carbon from
mineral coal comes from a non renewable
resource and extraction leads to large emis-
sions of CO2 to the atmosphere. This in dif-
ference to biochar from India where the car-
bon stored in the coconut shells are buried
in the sediments instead of being released
to the atmosphere, which would have been
the case if the biomass had been left to rot-
ten.
Recommends sustainable strategies
Many countries including Norway have
based their management of coastal zone
contamination on the precautionary princi-
ple evaluated through health and ecological
risk assessments. If the risk threshold values
are exceeded, there is in principle no limit
on how costly and resource intense reme-
dial methods that can be applied to remove
the risk.
- I mean that we in the future have to evalu-
ate environmental protection for coastal
areas based on several criteria not only risk
reduction, says Sparrevik.
Lower level of conflicts- also sustainable
management
Sparrevik has in addition to the Grenland
fjords studied remediation projects in Oslo
and Bergen in his PhD. In Oslo a remedial
project was conducted even though it was
heavily criticized by demonstrators and oth-
er stakeholders. Sparrevik has documented
that lack of proper involvement processes
played a big role in the social unrest created.
In Bergen several stakeholder groups were
invited to participate in the planning before
a remediation project was initiated. This is
untraditional, since the regulatory practice
is to involve stakeholders only in the formal
hearing process after all planning has been
conducted. Multi Criteria Decision Analysis
(MCDA) techniques were used as a way to
document and guide the involvement proc-
ess.
– Involvement is also an important part of a
sustainable remedial strategy, says Sparre-
vik. In addition involvement helps people to
feel safe and builds trust, he continues.
Sparrevik means that we better have to com-
bine environmental, economical and social
aspects in future projects than we do today.
- The principles are the same whether it is
contaminated fjord managemnt or other
projects where environmental restoration
plays a vital part. The models developed in
my PhD can hopefully contribute to a better
understanding of the processes needed, he
ends.
Contact information:
Magnus Sparrevik
Norwegian Geotechnical Institute (NGI)
magnus.sparrevik@ngi.no
PhD thesis submitted at Department of In-
dustrial Economics and Technology Man-
agement, NTNU
Supervisor: Annik Magerholm Fet, annik.
fet@iot.ntnu.no, Department of Industrial
Economics and Technology Management,
NTNU
Capping of contaminated sediments can help both the fjord and the
climate
-
by Magnus Sparrevik
RESEARCH
PhD THESIS