The Norrköping’s Pilot Site “Inre Hamnen” is located in the place of old gasworks that used to produce gas, tar and coke. Due to the industrial history, the site that will be transformed to a new city district with 800 apartments in the next decade, is heavily contaminated with tar, benzenes, cyanides and heavy metals. Before the transformation process can start, the site needs to be remediated.
To prepare for the remediation process, Norrköping has undertaken surveys to determine how and where the contaminants are distributed in the ground. The risk assessment shows that there are risks related to health and environment that are not acceptable even with the current use of the area – port and industrial use.
Soil remediation is an issue that needs to be evaluated taking into account environmental, social and economic aspects. Sustainability has been a guiding principle for the planning of Inre Hamnen and the same needs to be applied for the remediation of the contaminants.
Stakeholders were involved to ensure integration of sustainability aspects in to the process
To ensure that sustainability perspective will be included in the remediation process, Norrköping decided to organise a risk evaluation workshop with a range of stakeholder representing different backgrounds. Invitations were sent to Norrköping city planning department, the performing department “Tekniska kontoret”, the Norrköping owned company “Norrköping water and waste”, Norrköping Port, building companies, consultants involved in remediation and geotechnical issues, the council Board of Östergötland and the regulator of the municipality of Norrköping. Also representatives of the municipality of Västerås dealing with similar issue and the University of Chalmers participated.
The method used in the workshop is called SAMLA, developed by the Swedish Geotechnical Institute (SGI), which is a free tool that can be downloaded from Swedish geotechnical institute website (swedgeo.se). A representative from Swedish Geotechnical Institute assisted the city in leading the risk evaluation process. Around 30 participants were divided in six smaller groups and they were asked to evaluate the sustainability of four different remediation methods presented. The groups estimated the four alternatives with respect to 14 criterion that were divided into environmental, social and economic aspects that the soil remediation methods affect comparing to an alternative that nothing will be done to the site. Estimations were done by giving numbers from -3 to +3 on each aspect. By the end of the workshop, all groups had estimated the four alternative method’s implications on environmental, social and economic aspects. In the end, SAMLA tool was used to weight the results of the judgement made by all participants and the result were presented in graphics.
The results of the risk evaluation workshop will be used as a guidance in the decision-making on the remediation method to be used for the contaminated land in “Inre Hamnen” Pilot site.
Since some of the participants were not very familiar with the site, the workshop started with a guided tour. The group was lucky since there was ongoing archaeology surveys on this day. Archaeologist Magnus Stibéus showed the group a former two hundred year old street at the harbour.
Contact:
Elke Myrhede, Stadsbyggnadskontoret, Norrköping
Elke.Myrhede [at] Norrkoping.se
