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本研究在蘭嶼放射性待處理物料貯存場場區執行抽水試驗，以評估其含水
層之導水係數及貯水係數。本論文回顧等向性與不等向性含水層抽水試驗
之分析方法及適用條件，並舉蘭嶼試驗之實例，以說明正確判釋含水層種
類及選擇正確分析方法之重要性。裂隙含水層之導水係數通常有不等向
性;蘭嶼貯存場場區之含水層即屬此例。現場抽水試驗和 Papadopulos分
析法能有效地決定不等向性含水層之導水係數與貯水係數。在蘭嶼貯存場
進行之抽水試驗，其分析結果為最大導水係數之主軸方向大約為北偏東
84.2度、最大導水係數為0.0532(平方公尺/分鐘)、最小導水係數為
0.00975(平方公尺/分鐘)、最大與最小導水係數之比值為5.46、貯水係數
為0.103。本研究並在蘭嶼放射性待處理物料貯存場場區執行微水試驗，
以評估其含水層導水係數的分佈情形。本論文回顧拘限含水層與未拘限含
水層微水試驗之分析方法及適用條件。使用蘭嶼試驗之實例，以說明如何
在現場數據中，選取符合分析方法假設條件之數據來進行分析，而得到較
正確的分析結果。蘭嶼貯存場場區之含水層屬於未拘限含水層，本文應
用 Bouwer and Rice 分析法與 Hvorslev 分析法，來分析現場微水試驗
之數據，並由分析結果來描述含水層導水係數之分佈及含水層之特性。在
蘭嶼貯存場進行微水試驗，其分析結果如下：含水層之透水係數在安山岩
約為 0.00001∼0.000001(公尺/分鐘)、在珊瑚礁約為0.01∼0.001(公尺/
分鐘)、在碎屑岩約為0.001∼0.0001(公尺/分鐘)。含水層之導水係數在
安山岩約為0.001∼0.00001(平方公尺/分鐘)、在珊瑚礁約為0.1(平方公
尺/分鐘)、在碎屑岩約為0.01∼0.001(平方公尺/分鐘)。透水係數及導水
係數均有從海岸往山地方向遞減的現象。
A field pumping test was conducted on Lan-Yu island to evaluate
in-situ transmissivity and storage coefficient of the shallow
aquifer near the low level radioactive waste storage site. The
assumptions and methods for anazing field pumping tests were
reviewed for both homogeneous isotropic and homogeneous
anisotropic aquifers. The field example was employed to
illustrate how to select an apropriate model, isotropic versus
anisotropic, for analyzing the pumping test data. Anisotropic
transmissivity was found in fractured aquifers. Pumping tests
and Papadopulos's method are useful for determining
transmissivity and storage coefficient in anisotropic aquifers.
The reesult of pumpinng test is storage coefficient is 0.103,
the major transmissivity is 0.0532, the minor transmissivity is
0.00975, the ratio of the major to the minor transmissivity is
5.46 and the direection of the major trannsmissivity is N 84.2
degree E. Field slug tests were conducted on Lan-Yu island to
evaluate the distribution of the transmissivities of the
shallow aquifer near the low level radioactive waste stage
site. The assumptions and methods for analyzing field slug
tests were reviewed for both confined and unconfined aquifers.
The field examples were employed to illustrate how to analyze
the field slug test data with Hvorslev's method and Bouwer/Rice'
s method. The distribution of tansmissivities of the aquifer
was described based on the results of slug tests. The aquifer
conductivity of the aquifer is in the order of
0.00001∼0.000001(meter/minute) at the andesite, 0.01∼0.001(
meter/minute) at the coral reef, and 0.001∼0.0001(meter/
minute) at the pyroclastic rock. Extend to the transmissivity,
the aquifer transmissivity is in the order of 0.001∼0.00001(
Square meter/minute) at the andesite, 0.1(Square meter/minute)
at the coral reef, and 0.01∼0.001(Square meter/ /minute) at
the pyroclastic rock. The conductivity and transmissivity are
all deccreased from the seacoast to the hill.
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