Awareness maps

In collaboration with the local municipal health authority of Oslo, NGU is developing a survey map for contaminated land within the city of Oslo.

Every local authority is obliged by law (law on health service in local governments) to have an overview over the health status of local residents and the factors affecting this status. One such factor is considered to be contaminated land.

Possible contamination

Before carrying out excavation and construction work, an assessment has to made on whether the soil is contaminated or not. If there is reason to believe that the soil is contaminated, necessary surveys have to be carried out to map the possible contamination.

In a city, where pollution occurs both as diffuse and point sources (industrial sites), there is frequently reason to believe that the soil may be contaminated.

Helpful tool

An awareness map for contaminated soil is a very helpful tool in these cases. An awareness map shows where the soil could possibly be contaminated. The concept must not be confused with a pollution map; the awareness map only displays the areas where there is reason to believe that the soil is contaminated, not necessarily the places with documented contamination.

An awareness map for contaminated soil is produced on the basis of many sources of information:

• historical information
• systematic geochemical soil surveys
• existing environmental surveys
• overview of areas of urban soil
• other pollution sources (oil tanks, waste deposal sites, etc.)

In collaboration with the local municipal health authority of Oslo, NGU is developing a survey map  for contaminated land within the city of Oslo. The main goal of this project is to reduce the spreading of contamination to humans and the environment.

The project has the following main goals:

• to map the occurrence of metals and organic pollutants in the soil,
• to develop an awareness map  for contaminated soil,
• to develop guidance documents for public management on adherence to Chapter 2 in the Pollution limitation regulation,
• to develop a plan for disposal of contaminated soil, and
• to develop a method for the production of  awareness maps applicable to other cities.