Monitoring and assessment of environmental impacts of chemical spills in the Baltic Sea

The Finnish Environment Institute SYKE and Finland’s Ministry of the Environment initiated a project called EKOMON to prepare guidance on how to monitor the environmental impacts of accidental chemical spills at sea. This publication resulting from the project is intended to guide authorities responsible for post-spill environmental monitoring and assessment, and to help them to understand how complex issues they might be dealing with due to the wide range of chemicals currently transported. The main goal of the publication is to create better preparedness for establishing an effective post-spill monitoring programme especially in the Baltic Sea, area and it is primarily targeted at decision-makers responsible for the planning and implementation of environmental monitoring after a sudden chemical spill at sea. Worldwide, approximately 2,000 chemicals are transported by sea, either in bulk or in packaged form. During this decade particular attention has been focused more and more on the possibility of marine chemical accidents. Although the amount of transported chemicals is much less than that of oil and oil products, the risks related to possible chemical accidents are more difficult to identify. The main issue here is the very high variety and complexity of environmental risk profiles and potentials of the different chemical compounds. Risks posed by marine chemical spills depend on the accident scenario, prevailing environmental conditions, and the intrinsic properties of the spilled chemical. Chemicals can behave in a number of ways once spilled into the sea. Hazards to the environment can vary considerably depending on the chemical in question, and the impact can be acute or long-lasting. The occurrence of accidental chemical spills at sea requires an effective response that must include well-executed monitoring guidelines to assess environmental contamination and damage on the affected marine ecosystem. An impact assessment is crucial for the decision-making process concerning the selection and implementation of a prominent response plan. The objectives of the monitoring vary depending on the specific circumstances and environmental conditions related to the spill, and therefore they have to be set for each spill separately. The size of the spill, properties of the chemical, and the type of discharge (single or continuous spill) as well as the characteristics of the receiving environment are the main factors defining the monitoring requirements. Choosing of similar reference areas and/or comparisons with pre-existing baseline data are key components for post-spill monitoring. Finally, environmental monitoring can be used to demonstrate ecological damage and economic losses in the context of spill-related claims and compensations. The EKOMON report can be seen as the first step for the better preparedness for post-spill monitoring especially in Baltic Sea area. In the future these guidelines should be further developed to be more operational with the practical goal being a monitoring system, which in the event of an accident allows a rapid organization of the team responsible for monitoring and identification of its ecological consequences