A note on terminology is necessary. In common usage the term `environmental impact assessment´ (EIA) often can refer to both the process of assessing environmental impacts and the document produced as a result of this process. In US law and regulations the document is called an environmental impact statement (EIS), and an environmental impact as sessment refers to the process. In other countries (including Thailand) the term is used in both its meanings. For clarity, we will use EIS for the document and EIA for the process.