都市地域 非點汚染 特性과 降水利用에 關한 硏究

Abstract

Conclusion is as in the following that estimate reduction of source loadings for operation of reduction facilities of Non-point source of Gyeonggi-do A city implementing Management of Total Maximum Daily Load and reasonable policy and suitability of treatment facilities. Analyzed removal efficiency of pollutant according to rainfall fluctuation, organic matter, nutrient salts, heavy metal, coliform bacillus. The analysis result of treatment efficiency for treatment facility of Non-point source pollution appeared that treatment efficiency is 8% more highly than design efficiency in all point and satisfied removal efficiency by the reduction facility which presents to management for Non-point source pollution of Ministry of Environment a guide to office routine. Result from monitering treatment efficiency of natural facility and system facility is natural facility →CDS-MFS→HDS-FSF order appeared and with the fact that the treatment efficiency of the natural facility which advises from the Ministry of Environment is high was investigated. The point by BODwas observed in a high level at the points of the Gonjiam bridge, the Mokhyeon downstream , the Beolwon stream which in domestic wastewater and Non-point source pollution flow COD was observed to be higher on the Green park, the Gonjiam bridge and the Beolwon stream with pollutant sources of roads and residential areas than the Whasin heavy machinery. Higher pollutant concentrations were observed on the Tanbeolcho bridge and the Green Park with woodland, road and residential area for SS and the Mokhyeon downstream and the Gonjiam bridge for T-N, T-P, nutrient salts and the Beolwon stream that flow through the downtown area for T-N. The heavy metal was detected above of 1 mg/L in the Mokhyeon downstream and the Whasin heavy machinery where flow through early rainfall of road and watercourse. Cu, Pb, Zn were contained in early rainfall because of tire road friction and livestock excretions flowing in road. Reduction plan goals of average a year for non-point source pollutant reduction facility six points in management plans of Total Maximum Daily Load that A city implement is BOD 4.3kg/day and reduction of average a year of six point is 6.8256kg/day, which showed 158.7% more highly than goal after implementation. When tries to observe a point by reduction load quantity the Beolwon stream, continues treatment facility, showed almost reduction load quantity of average a year because point of the Beolwon stream has a lot of inflow quantity and stream water constantly flow every day. Reduction load quantity of average a year showed that BOD is high in the Gonjiam bridge and the Mokhyeon downstream which is combined sewer and low in the Tanbeolcho bridge and the Green park. COD highly showed in the Gonjiam bridge and the Tanbeolcho bridge and the Green park is lowest. SS showed highest in the Tanbeolcho bridge which is caused pollution from stormwater to downtown and woodland and the Whasin heavy machinery is low.

Reduction load quantity of average a year of T-N and T-P showed highly in the Gonjiam bridge and lowly the Green park . Although the concentration of Green park was highly measured, Reduction load quantity of average a year lowly showed because of small facility capacity. When inspected the coliform in 2010 year may between september, the coliform of 120～40/100 ml was detected so unfit for water reuse. So, should install facility can disinfect coliform. Because manage to separate graywater and water reuse in the sewerage law, confusion of people is worried so need to polysynthetically manage related regulations. Media exchange cycle of deviced facility is when removal efficiency of BOD is subminimum(40∼60%), clean by water at first and when exceed twice, change. The result which measures 2010 year precipitation preparation contaminants when precipitation is 6∼20 ㎜, pollutant concentration increases and then distribution of concentration constantly appeared from the average annual rainfall. So need to highly change urban non-point source pollutant initial rain assessment probability to 90% precipitation. When decide treatment facilities scale, it is efficient that consider pollutants removal time, because pollutants removal of initial rain require about three hours. When remove road dust by water spray vehicle, 44% is reduced. Should supplement related regulations to accept to allocation of pollutant loads where implement Management of Total Maximum Daily Load. Because non-point source BOD standard reduction loadings of road cleaning is about 8.6%.