This project was to assist the EPA to investigate the groundwater quality for the high potential polluted areas and the important groundwater resources areas, as well as developing management measures of groundwater monitoring wells. Regarding the groundwater investigation of high potential polluted areas, this project adopted the achieved results from 2009 and selected 33 monitoring wells within a radius of 1 km from 15 industrial parks, 2 science parks and one export processing zone to sample and analyze the groundwater quality. In addition, 5 temporary wells were installed and sampled from Jhongli and Shulin Industrial Parks, respectively. Investigation results indicated that one temporary well from Jhongli had TCE concentration above the control standard and offsite concentration was approximately 50% of the control standard. It is recommended to continue monitor and investigate the contamination. At Nantze Export Processing Zone, chlorinated volatile organic compounds (CVOCs) were non-detected at offsite monitoring wells, except one well located near Kaohsiung Petroleum Refinery of CPC Corporation, Taiwan, which had benzene concentration detected above control standard. Sampling results for metals, persistent organic pollutants, TPHs and other analyzing parameters did not indicate any unusual condition. Slight concentration of CVOCs, total phenols, BTEX and MTBE had detected from 30 existing monitoring wells. Finally, based on the investigation result from 2009~2010, classification and strategies for addressing unusual monitoring results from 21 high polluted areas were proposed.
For the important groundwater resource areas, this project chose Choshuichi Groundwater Basin and Pingtung Plain Groundwater Basin as the study area. Based on the local hydrogeology data, agriculture/industrial activities and existing monitoring results, a total of 37 existing monitoring wells were selected for the analysis of groundwater quality. Erlin monitoring well-Water Resources Agency had vinyl chloride concentration detected above control standard. It was proposed to conduct a thorough investigation of local groundwater usage. Also, it was suggested for Water Resources Agency and Taiwan Water Corporation to conduct additional groundwater monitoring. In addition, installation of monitoring wells was proposed to the local Environmental Protection Bureau for the purpose of delineating contamination extent. If necessary, contaminated groundwater restricted usage area would be proclaimed according to Article 27 of the Soil and Groundwater Pollution Remediation Act. Slight concentration of CVOCs, total phenols, BTEX, MTBE and pesticide had detected from 21 existing monitoring wells. It was suggested to continue monitor the groundwater quality. Additional sampling frequency or sampling locations will be added based on the future sampling results.
For the management of monitoring wells, this project performed the trend analysis of groundwater quality of 431 regional monitoring wells in 10 national groundwater districts by Mann-Kendall Test. It was suggested to lower the monitoring frequency of 343 regional monitoring wells from four times to two times a year. According to the reorganization of the government, “Ministry of Environmental Resources” was established. This project also assisted the EPA to assess and develop “Promotion of Groundwater Monitoring Management Plan”.
As for the other related administrative tasks, this project assisted EPA to: 1) hold two separate discussion forums for the different levels of Environmental Protection Agencies and different industrial management representatives; 2) review and develop the groundwater monitoring management assessment protocol for the local environmental protection organizations; and, 3) complete drafting 12 related regulations and administrative rules.