Kuyu ve Akifer Testlerine Uygulanan Analitik ve Sayısal Yöntemlerle Hidrolik İletkenliğin Belirlenmesi

Bu çalışmada, kuyu ve akifer testlerinden elde edilen su seviyesi değerleri kullanılarak analitik ve sayısal yöntemlerle akiferin hidrolik iletkenliğinin belirlenmesi amaçlanmıştır. Çalışma kapsamında, Neojen Mühendislik tarafından Bursa Küçük Sanayi bölgesinde bulunan basınçsız bir akiferde aralarında 33 m mesafe bulunan iki adet kuyu açılmıştır. Kuyulardan birinde farklı hacimler kullanılarak inkişaf öncesi ve sonrası olmak üzere toplamda 18 adet slug test yapılmıştır. Analitik yöntem olarak Bouwer-Rice ve Dagan metotları, sayısal modelleme için yeraltı suyu akım problemlerini sonlu farklar metodu ile çözen MODFLOW yazılımı kullanılmıştır. Diğer kuyuda ise pompalama testleri yapılmıştır. Kademeli pompalama test verilerine Hantush-Bierschenk ve Rorabaugh metotları uygulanmış ve debi-düşüm eğrileri elde edilmiştir. Bunlara ek olarak, geri dönüm testi ve değişken debili pompaj testi ile hidrolik iletkenlik belirlenmeye çalışılmıştır. MODFLOW’da grid çözünürlüğüne ve özgül verime dayalı farklı durumlar için simülasyonlar yapılmıştır. Sonuç olarak, inkişafın kuyu performansını belirgin bir şekilde arttırdığı, slug testte kullanılan hacmin sonuçları etkilemediği ve ayrıca MODFLOW ile modellenen farklı pompalama testlerinin verdiği hidrolik iletkenlik değerlerinin birbirine yakın olduğu görülmüştür

Anahtar Kelimeler:

Hidrolik iletkenlik, slug test, geri dönüm testi, değişken debili pompaj testi, kademeli pompalama testi, MODFLOW

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Determination of Hydraulic Conductivity Using Analytical and Numerical Methods Applied to Well and Aquifer Tests This study aims to determine the hydraulic conductivity of aquifers by analytical and numerical methods applied to water level data obtained from well and aquifer tests. Two wells 33 meters apart were drilled in an unconfined aquifer in Bursa Küçük Sanayi region by Neojen Mühendislik. In one of the wells, a total of 18 slug tests were performed using different volumes before and after well development. Bouwer-Rice and Dagan methods were used as analytical methods and MODFLOW software, which solves groundwater flow problems using method of finite differences, was used for numerical modeling. In the other well, pumping tests were performed. Hantush-Bierschenk and Rorabaugh methods were applied to the data from step-drawdown tests and discharge-drawdown curves were obtained. In addition to these, recovery test and multirate test were performed to determine the hydraulic conductivity. In MODFLOW, simulations were made for various cases related to grid resolution and specific yield. It was observed that well development significantly contributes to well performance and the volume used in slug tests does not affect the results. In addition, different pumping tests modeled in MODFLOW yielded similar values of hydraulic conductivity

Keywords:

Hydraulic conductivity, slug test, recovery test, multirate test, step-drawdown test, MODFLOW,

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