EPA-103-GA13-03-A273

103

12,900 千元

2014/10/31

2016/03/31

陳慶宇

土污基管會

楊宜寧

艾奕康工程顧問股份有限公司

土壤及地下水

傳輸模式、河川、水庫、河口

Transmission model, river, reservoir, estuary

蔡昀達

02-27200999#6219

darren.tsai@aecom.com

本計畫目的在於應用適當的水理水質模式，強化及進行底泥污染傳輸模擬，依模擬結果提出合適之總量管制管理策略及建議，俾符合環境相關法令基準。 本計畫蒐集國內主要水庫及河川流域背景資料、水體水質污染現況、歷年底泥監測結果等基本資料蒐集，並依據地區、污染潛勢高、公共用水、同屬相同流域及相關配合計畫等原則，擇定阿公店水庫、河川及河口為目標水體，規劃整體補充調查內容，強化流域整體模式之率定及驗證，並執行後續模式情境模擬，以作為後續管理建議之依據。 依據本計畫補充調查結果顯示，阿公店水庫僅重金屬鎳及砷有超過底泥品質下限值(增加檢測頻率值)之情形，其餘低於目前之法規限值。然庫區內並無明顯或長期持續的污染源排放情形，且重金屬砷應屬地質元素，故在污染情境分析上，考量現有相關參數演算資料以及水體與底泥之管制項目與限值，選定鎳為關切污染物，進行模式率定及驗證，底泥污染傳輸模式模擬結果與三次採樣結果相近，均屬於可信賴且高準確預測。此外，由三次採樣結果顯示，底泥鎳濃度變化甚微，介於24.4~35.6 mg/kg之間，主因為於庫區內流速甚低，底泥傳輸效果不明顯所致。阿公店溪底泥除重金屬鋅及鉻超過底泥品質上限值(風險評估啟動值)及銅、鎳、砷、汞、可氯丹及二氯二苯基三氯乙烷(DDT)及其衍生物超過底泥品質下限值(增加檢測頻率值)外，其餘則低於目前之法規限值。考量阿公店溪除上游河段，其餘河段底泥鋅均高於底泥品質指標上限值(風險評估啟動值)，故以重金屬鋅為目標污染物。此外，由於河川底泥重金屬鋅有高於下限值(增加檢測頻率值)之情形，遂亦針對鋅進行模式率定及驗證，並進行各項污染情境分析，其結果顯示對岡燕橋以下進行清淤(12.45 km ~ 出海口)後，並對全流域削減污染量65%，可達全河段模擬五年之結果均低於底泥下限值(增加檢測頻率值)，可維持河川整體環境並減少發生危害之機率。 本計畫另一項工作重點為辦理六場次研習會及一場次採樣觀摩會。殷鑑於底泥污染領域為國內環境保護新領域，各相關法規之宣導推動、目的事業主管機關權責義務及整治工作之推動尚未臻落實完善，故為加強推動底泥品質管理工作與落實法規執行宣導事宜，內容包括現階段底泥管理相關法規架構、採樣計畫書撰寫實例、底泥檢測技術介紹、國外底泥處理及整治技術介紹等，並藉由會議之各方意見回饋，及綜整國內外底泥管理法規與策略，提出未來底泥品質法規研修之相關建議。

傳輸模式、河川、水庫、河口

書面正式報告本文.pdf

24MB

2016/7/1 上午 12:00:00

The objectives of the project are to development and enhance the sediment transport model by applying the proper hydraulic and water quality models. For the purpose of compliance with relevant environmental regulations, the strategy and recommendation for the justified TMDL will be suggested based on the results of sediment modelling. The project first collected the background information of major reservoirs and rivers, current water body pollution condition and historical sediment monitoring results. According to the criteria of location, potential pollution, public water supply, and same water basin factors, Agongdian Reservoir, River and Estuary was selected as the project target waterbody to conduct the planning of supplementary investigation and enhance the water basin wide model calibration and verification. The scenario simulations were also modeled as the basis of follow-up management. Project supplementary investigation results indicated concentration of nickel and arsenic in Agongdian Reservoir sediment exceeded the lower limits of Sediment Quality Index, other heavy metals could meet the current regulatory limits. Since there is no pollution coming into the Reservoir, the arsenic is from natural background. Nickel was selected as the concerned pollutant to be modelled after considering of relevant calculation data, pollution control items of waterbody and sediment. It shows the simulation results of sediment transport model are all considered reliable and high-accuracy prediction. The monitoring results show the change of nickel concentration in sediment is not significant. The major reasons include the slow speed of water flow in reservoir and the effect of sediment transport is not significant. Concentration of Zinc and Chromium in Agongdian River sediment exceeded the upper limits of Sediment Quality Index, copper, nickel, arsenic, mercury, chlordane and DDT exceeded the lower limits of Sediment Quality Index. Considering the exception of River upper section, the concentration of sediment zinc in the reaming river section exceeded the upper limits of Sediment Quality Index. Zinc is set to be the target pollutant in the modelling. Sediment nickel concentration exceeded the lower limits of Sediment Quality Index, therefore nickel was also modeled. Scenario simulation results indicated that sediment dredging from GunYen Bridge (12.45km) to River mouth will reduce 65% of water basin pollution mass and sediment quality in entire river can meet the lower limits of Sediment Quality Index in the simulation period 5 years. Another major task in this project was to conduct 6 training workshops and 1 sediment sampling demonstration. Given sediment contamination is a new field in Taiwan, the promotion of revenant regulations, industry right and duties of the competent authority, promotion of remediation work right are all not implemented well. The course content included sediment law framework, example for sampling plan preparation, sediment investigation technologies, sediment management strategies and international remediation technologies introduction. After the workshop, the feedbacks could be the references for the future implementation of sediment regulations.

Transmission model, river, reservoir, estuary