This project involves the installation of a large-scale bottom-mounted offshore windfarm about one kilometer from the coast. At the time of our assessment, environmental impact assessments for offshore wind power projects were still in their infancy, and assessment items, study methods, and other aspects of environmental assessments were not yet fully established. As a result, new views and opinions that had never been encountered before arose at each review board meeting. With a lack of precedents to rely on, we executed the procedures for the document on primary environmental impact consideration, scoping document, draft environmental impact statement, and environmental impact statement based on the Environmental Impact Assessment Act.

The environmental assessment items selected were noise, ultra-low frequency noise, water turbidity, wind turbine shadows, underwater noise, animals (birds), marine animals, marine vegetation, landscapes, and waste. Given that part of the project’s aim is to contribute to the local economy, we partnered with a local measurement and analysis company and natural environment research company that are familiar with the proposed site and conducted on-site studies with advice from local university professors and other experts. We also assembled simulations covering living environment-related items as well as expertise on natural environment-related items (including know-how from overseas), and conducted predictions and assessments based on views expressed by the review board.

When we began the procedures for this project, environmental impact assessments for offshore wind power had already been conducted by several projects in other sea areas. However, only a few involving bottom-mounted offshore wind farms near coastal areas had gone as far as the environmental impact statement stage amid local opposition and stringent positions by government ministers. This project was the first involving bottom-mounted wind turbines to complete everything from the submittal of the document on primary environment impact consideration to the inspection of environmental impact statement within a procedure period of about four years.