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Since the building of the Copenhagen Metro began in 2011, DHI has been responsible for assessing all substances in the chemical products used for the construction work. The latest metro extension was inaugurated in September 2019 and new extensions are under construction. Up till today we have assessed more than 200 different chemical substances.
The chemicals occur in many diverse products such as grouting chemicals used for casting of tunnel walls; foams, polymers, grease and sealants for tunnel boring; and water treatment chemicals for groundwater pumped up during construction work and discharged to public sewers. Our assessment also includes risk assessment of the excavated muck used as build-in material.
Gained valuable knowledge
To examine the chemical products, all suppliers are requested to provide detailed composition information about their products. In a preliminary screening, the substances are grouped into A, B and C substances. Group C contains low-risk substances such as readily biodegradable substances, while group A contains high-risk substances that may seriously harm health or the environment.
After the initial screening we carry out a meticulous risk assessment of all A and B substances. This includes an assessment of the substances’ contact with groundwater and possible impact on the drinking water quality or their fate and effects in sewage treatment plants and in surface water.
Through the projects, we have gained very valuable knowledge of chemicals used for large construction works such as underground railways and similar.
The first assessment project was carried out on behalf of the general contractor Copenhagen Metro Team. For the ongoing extension of the Metro, it is a requirement from the contractor that the chemical product suppliers provide the required information to obtain authorisation to use the products. The authorisation is given by the municipalities where the Metro is built.