산업단지 사업에서의 수질오염 영향범위 설정방안

Abstract

Guidelines for establishment of the following water quality impact scope when developing industrial complexes. Environmental Impact Assessment (EIA) anticipates and assesses environmental impact arising from pursuit of a particular project before its implementation, and plays an important role in setting the appropriate scope of impact and providing reliable environmental assessments. For the water environment, forecasting of impact begins with selecting the water quality monitoring stations, and establishing impact scope. However, as there are no clear standards with respect to selection of locations for water quality monitoring stations during environmental assessment, various difficulties have arisen in establishing and forecasting impact scope. Although regulations on selection of monitoring stations exist, as found in the "Water Quality Monitoring Network Operations Plan (2010 Ministry of Environment)," the "Water Pollution Process Testing Methodology (Ministry of Environment Notification No. 2004-188)," and the "Guidelines on Drafting of EIA statements for Different Categories of Projects (Ministry of Environment, 2009)," most have stated location and selection requirements in only general terms, i.e. "areas forecast to receive impact." Accordingly, this study proposes guidelines for selection of locations and impact scope for water quality monitoring stations based on analysis of existing case studies and EIA statements for industrial complexes. This study undertook analysis of data on selection of water quality monitoring stations in EIA statements for industrial complexes from 2009-2010. While such analysis of stations based on EIA statements may differ from scientific approaches, it can provide an experiential basis for approaches to the issue. References to existing research included the "Study on Standard Distances from Water Quality Protected Areas, (Ministry of Environment, 2003),"and the "Study on Propriety of Plant Site Location Regulations in Water Source Upstream Areas (Ministry of Environment, 2008)." We assessed appropriate impact scope for water pollution in environmental assessment through review of statistical data and theoretical approaches through analysis of EIA statements. The results were reviewed through correlation analysis of the actual times and concentration levels of pollution, and water quality modeling. The water pollution impact scope as determined through water quality modeling was found to vary in accordance with a number of conditions, including the nature of the pollution source (i.e. concentration and outflow of discharged pollutants), as well as concentration and outflow levels of discharging rivers, and concentration and flow levels of inflowing streams and conjoining rivers, as well as dilution effects caused by conjoining rivers. Accordingly, this study establishes the following water quality impact scope, and suggests that water quality studies and forecasting, detailed assessment of water quality, and environmental impact studies be performed based on this impact scope. First, impact scope should be set at locations whose mixed concentration weighted values for water pollution were reduced by 50%. Impact scope for mixed concentration must be determined in consideration of flow quantity and concentration of pollutants, flow quantity and concentration of discharging rivers, and the form of the river etc., and must also consider flow quantity and concentration etc. of branches of rivers and conjoining rivers. In order to analyze changes in mixed concentrations of pollutants added to rivers, simple mixed formulas and time and concentration correlated analysis as well as water quality modeling can be used to review general impact. Second, impact scope should be expanded to environmentally sensitive areas in respect of water quality impact from projects. If there are water source protected areas or catchments etc. in surrounding rivers for a prospective site location, impact scope must include those areas. Furthermore, if there are specific wild animals and plants in the downstream of the discharge river, the impacting river must also be included. Consideration must also be made of the actual use of rivers, including urban rivers that pass through downtown sections, as well as rural rivers protected as natural resources. Third, since industrial complexes typically produce pollutants like heavy metals, whose effect on health and the ecosystem is both direct and substantial, monitoring via follow-up environmental impact studies, after establishing the main pollutants, will be required. This study is intended to propose more concrete guidelines with respect to the establishment of existing water quality impact scope, which are largely general and abstract. When developing industrial complexes, impact scope should be submitted in consideration of the characteristics of regional rivers and the industrial complex in question, rather than applying a representative value throughout the whole country, or specifying a single uniform distance, as water pollution impact scope varies depending on the characteristics and flow quantity of each river, while pollution sources themselves are varied in form. By more clearly and concretely establishing "areas receiving significant environmental impact from development of industrial complexes" through the impact scope suggested herein, the findings of this study can increase the efficacy of EIA by providing better forecasting and management of impact.