EPA-104-L101-02-202

104

53,000 千元

2015/04/01

2018/03/31

吳坤立

監資處

程凱麟

清華科技檢驗股份有限公司

環境監測及檢測

水質監測、水質標準、方法偵測極限

Water Quality Monitoring, Water Quality Standards, Method Detection Limit

許姝羚

03-5545022#215

meg@tsing-hua.com.tw

本計畫主要針對中區五縣市各類水體水質監測，掌握各水體水質隨時間的變化趨勢，並進行各水體污染評估分析，以提供環保單位污染防治決策之參考。 河川水質計有 18 條河川主支流，69 個監測站，每月監測一次。監測結果顯示，中部地區河川屬未(稍)受污染等級，以西湖溪流域占最高比例(98 % ~ 100 %)，屬嚴重污染等級，以北港溪流域占較高比例 (19 % ~ 27 %)。部分河川因河道屬礫石狀，易受降雨沖刷河道造成水中懸浮固體偏高，例如大安溪流域、烏溪流域、濁水溪流域及、新虎尾溪流域及北港溪流域等。於天候良好狀況下，中部地區河川以大甲溪流域以北之河川水質狀況較佳，僅於下游測站有污染累積情形。大甲溪流域以南流域之河川，可能受工業廢水及民生污水排放等因素，水中污染物濃度相對較高。 海域水質計有 23 個測站，分屬甲類及乙類海域環境。每季監測一次。監測結果顯示，均符合所屬各類海域海洋環境品質標準。各沿海海域水質於距離陸源排放較近之測站，水質狀況較易變動，整體水質狀況與歷年監測結果相近。 海灘水質計有 2 個測站，於 6 至 9 月每月監測一次。崎頂海水浴場及通霄海水浴場監測結果以水質分級評估，均屬優良級佔最高比例，結果顯示水質狀況良好。 水庫水質計有 8 座水庫，每季監測一次，監測結果顯示，日月潭水庫水質屬貧養等級比例最高，大埔水庫水質屬優養等級比例最高。大埔水庫卡爾森指數有下降趨勢，明德水庫及頭社水庫卡爾森指數有上升趨勢，其餘水庫各季次水質變化，與歷年結果相近。 地下水水質監測共計有 5 縣市，112口監測井，其中 45 口監測井每季監測一次，36 口監測井每半年監測一次，31口測井每年監測一次。全部地下水監測井揮發性有機物每年監測一次。監測結果顯示，地下水監測井水質超過地下水第二類監測標準之項目與歷年結果相近，主要以氨氮、鐵及錳為主。彰化縣及雲林縣境內監測井之氨氮測值，較其他縣市之測值為高。地下水揮發性有機物監測結果，僅二口監測井分別檢出微量甲基第三丁基醚及氯仿，測值均未超過地下水第二類污染監測標準。各監測井之水質，以Stiff水質形狀圖與Piper水質菱形圖方式評估，各季次變化大致呈現一致趨勢。

水質監測、水質標準、方法偵測極限

EPA-104-L101-02-202 (期末報告).pdf

7MB

2018/6/1 上午 12:00:00

The aim of this project was to properly understand the changing trend of water quality in those types of water bodies over the passage of time by monitoring the water quality of rivers, beach, oceans, reservoirs and groundwater in the five counties located in the central part of Taiwan. Water quality was assessed by sixty-nine water-monitoring stations along eighteen rivers and affiliated branches, which monitoring was conducted once every month. The results showed that in central Taiwan, most of monitoring stations (about 98%~100%) were categorized to non(slightly)-polluted level in the Shihu river Basin, besides, the highest ratio of monitoring stations (about 19%~27%) categorized to severely-polluted level was observed in the Beigang River Basins. The river channel in some waterways consisted of loose gravel so rain water runoff led to a higher level of suspended solids in the waters, which examples include the Da-an River, Wu River, Jhuoshuei River, Sin HuWei River and Beigang River basins. The better water quality from the rivers north of the Dajia River Basin (upstream) can be observed, which may resulted from good weather conditions, however, the down stream monitoring showed that accumulation of pollutants was observed, which may resulted from the discharge of industrial effluent and household sewage. The sea water quality monitoring consisted of twenty-three monitoring stations located in Class-A and Class-B marine environments, which monitoring was conducted once every season. There was a significant variation of water quality can be observed in the monitoring stations which placed near terrestrial discharge sources, however, overall water quality was similar to the previous reported results in recent years. The beach water quality consisted of two monitoring stations, which were monitored once per month from June to September. The findings from Qiding beach and West-Ocean Educational Sea World beach were classified, the results showed that not only the water quality was normally excellent but also the highest ratio was classified as “Good” category. The water quality of eight reservoirs was monitored once every season. The results indicated that there was the highest proportion of oligotrophic ratings for the water quality of the Jih-Yueh-Tan Reservoir, on the contrary, there was the highest proportion of eutrophic ratings for that of the Ta-Pu Reservoir. In addition, a significant decrease of the Carlson trophic state index was observed in the Ta-Pu Reservoir; however, a significant increase of that was observed in the Ming-Te Reservoir and Tou-She Reservoir, while the water quality changes of each season at the other reservoirs were within historical norms. The groundwater quality monitoring was conducted through one hundred and twelve wells spread across five counties in past years. For general monitoring items except volatile organic compounds (VOCs), the forty-five monitoring wells among the total ones were conducted once every season, other thirty-six monitoring wells were conducted once every six months, the other thirty-one monitoring wells were conducted once a year, respectively; however, as for VOCs, which was monitored once a year for total one hundred and twelve wells. The results showed that the main findings including ammonia nitrogen, iron, and manganese, exceeding groundwater Class-B monitoring criteria were similar as previous reported results in recent years. Ammonia nitrogen readings from monitoring wells in Changhua County and Yunlin County were higher than that from other regions. Moreover, the groundwater monitoring of VOCs showed that a slight concentration of methyl-tert-butyl ether and chloroform was measured within only two wells, which did not exceed the second category groundwater pollution control standard. Eventually, the water quality of each monitoring wells was evaluated by means of both Stiff diagram (Stiff pattern) and Piper diagram, which exhibited a consistent trend for the changes of each season.

Water Quality Monitoring, Water Quality Standards, Method Detection Limit