透地雷達應用於地下輕–非水相液體污染探測之研究

The Research on the Application of Ground-Penetrating Radar in Underground LNAPL Contamination

彭騰衝(Teng-Chong Peng)

指導教授 ： 陳水龍

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2007年)

https://doi.org/10.6841/NTUT.2007.00096

摘要

常見的地下有機溶液污染，皆屬輕-非水相液體(Light Non-Aqueous Phase Liquid，LNAPL)，其易隨雨水和地下水而逐漸擴散，因此等到有所察覺，該污染已十分嚴重。但傳統的破壞性檢測(destructive surveying)不易確切探知地下污染範圍，因此，一些非破壞檢測(non-destructive surveying)逐漸被應用與研究，透地雷達(ground-penetrating radar, GPR)即是其中之一。GPR乃利用不同物質對電磁波不同之穿透與反射特性，探求地下土層中之地物特徵。
本論文以嘉義縣水上鄉之現地污染為分析案例，參考地文資料與地理條件規劃出GPR測線進行施測，參考文獻中之污染特性與電性特徵，進行透地雷達施測，取透地雷達結果與地電阻進行比對，證明GPR探測LNAPL之可行性；描繪出污染擴散區域後，參照地下水位監測與鑽探報告結果，驗證GPR探測之準確性；最後，結合初步之Matlab影像處理，利用軟體劃分出污染程度，以此降低GPR對人為辨識之依賴。
研究結果證實，GPR確實能探測LNAPL之存在與範圍，且其結果頗為吻合，而初步結合影像處理之成果亦是可行，證實了GPR結合影像處理確有其發展潛力。

關鍵字

透地雷達 ； 非破壞檢測 ； 地下污染 ； 輕-非水相液體 ； 影像處理

並列摘要

The common underground organic solution pollutions are mostly the results of Light Non-Aqueous Phase Liquid (LNAPL), whose nature allows the dispersion with surface runoff and groundwater. Therefore, such pollutions are seldom detected until it is too late. However, the traditional destructive surveying techniques are unable to provide an accurate detection of the extent of LNAPL. Thus, several non-destructive surveying methods are extensively studied and applied, while one of them is the ground-penetrating radar (GPR). GPR explores the anomalies and formation in the underground geology by taking the advantage of the capabilities of penetration and reflection in different materials to electromagnetic waves.
In this study, a pollution site at Shui-Shan, Chiayi County is introduced for the analysis. By studying historic geologic information and geographic conditions, the GPR profiles are plotted for measurement. The measurement using GPR is conducted by consulting the characteristics of pollution and electricity. The results are compared with those from resistivity surveys to verify the feasibility of using GPR for underground pollution survey. The accuracy of GPR survey is verified by comparing groundwater table monitoring results and bore logs after the extent of pollution is plotted. Finally, the program Matlab is used for preliminary image processing, and the levels of pollution are classified with applicable software in order to minimize human identification and intervention in GPR results.
The result of study shows that GPR does display the capability to detect the existence and extent of LNAPL, and the results are relatively accurate. In addition, the preliminary combination of image processing gives an encouraging result. It is proven that the combination of GPR and image processing does demonstrate a promising future.

並列關鍵字

Groun-Penetrating Radar ； Nondestructive Surveying ； Underground Contamination ； Light Non-Aqueous Phase Liquid ； Image Processing

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