• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.105-109
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• 2005

폐기물매립장에서 발생하는 침출수의 확산정도를 정량적으로 추정하기 위해 매립장 주변에 설치되어 있는 2개 지하수공(BWM-1, BWM-2)에서 단공주입양수 추적자시험이 실시되었다. 브롬(Br-) 이온이 추적자로 이용되었으며, 추적자시험은 주입단계, 체이서단계 및 양수단계의 과정으로 실시되었다. 시험대상 구간은 지표면하 $20{\sim}24m$에 해당하는 파쇄암반층이며, 주입율과 양수율은 추적자시험 이전에 실시되어진 양수시험 자료에 의해 산정되었다. BWM-1 지하수공의 단공주입양수 추적자시험에 의해 추정된 종분산지수는 공극율이 0.01, 0.05, 0.1 및 0.5인 경우에 각각 9.50, 4.25, 3.00, 1.34cm 이다. 시험대수층의 공극율은 대략 $0.05{\sim}0.20$의 범위이며, 따라서 종분산지수는 $2{\sim}4cm$인 것으로 추정된다. BWM-2 지하수공의 단공주입양수 추적자시험에 의해 추정된 종분산지수는 공극율 0.01, 0.05, 0.1 및 0.5인 경우에 각각 3.32, 1.49, 1.05, 0.47cm 이다. 시험대수층의 공극율은 대략 $0.05{\sim}0.20$의 범위이며, 따라서 종분산지수는 $1{\sim}2cm$인 것으로 추정된다. 폐기물매립장에서 침출수가 유출할 경우, BWM-2 지하수공 주변의 파쇄암반층이 BWM-1 지하수공 주변의 파쇄암반층보다 침출수 확산이 2배 정도 빠르게 발생할 것으로 추정되었다.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.53-60
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• 2006

Single well injection withdrawal tracer tests with bromide were carried out at two wells developed in a horizontally heterogeneous fractured rock. The hydraulic conductivity of TW-1 well was 5 times larger than TW-2 well, and the average linear velocity of TW-2 well was 1.8 times faster than TW-1 well. The difference of hydrodynamic dispersions of two wells in the fractured rock was studied with the analysis of concentration breakthrough curves and cumulative mass recovery curves of bromide with withdrawal time, and the estimation of average travel distance, pore velocity, longitudinal dispersivity and longitudinal dispersion coefficient. The average travel distances of bromide were estimated to be 3.00 m in TW-1 well and 5.62 m in TW-2 well. The average pore velocities for the injection/withdrawal phase were estimated to be $4.31\;{\times}\;10^{-4}\;m/sec$ in TW-1 well and $8.08\;{\times}\;10^{-4}\;m/sec$ in TW-2 well. Average travel distance and pore velocity were higher in TW-2 well because of small effective porosity. Longitudinal dispersivities were estimated to be 28.73 cm in TW-1 well and 18.49 cm in TW-2 well, and bromide transport was 1.55 times faster in TW-1 well. Longitudinal dispersion coefficients were estimated to be $5.14\;{\times}\;10^{-6}\;m^2/sec$ in TW-1 well and $6.06\;{\times}\;10^{-6}\;m^2/sec$ in TW-2 well, and diffusion area was 1.18 times larger in TW-2 well.