자연암반균열에서 오염물질 이동실험을 하였다. 실험은 크기가 91.5×86.5×49(cm)이고 평균균열폭이 0.6 mm인 자연암반균열에서 비수착성핵정인 우라닌과 수착성핵종인 세슘을 사용해 이동현상을 관찰하였다. 오염물질은 균열 한쪽면에서 계단함수로 주입하여 맞은 편 균열면으로 이동하도록 하였다. 유속은 20 ml/h, 선속도는 3.71 cm/h였다. 전체균열폭이 일정치 않음에 따라 오염물질은 흐름저항이 가장 작은 균열틈을 따라 이동하는 국부통로 이동현상을 보였다. 전체계에서 수리분산은 국부통로이동에 주로 기인한 것으로 나타났다. 오염물질은 지하수에 비해 매질에 수착, 매질로의 확산 등으로 이동이 지연되었다. 수착성핵종인 세슘의 경우 이동지연효과는 매질에 수착능이 결정적인 역할을 하였다. 유출곡선을 해석해를 사용해 모사한 결과 수착과 수리분산에 민감하게 반응하고 암반매질로의 확산도에는 큰 영향이 없었다.

Experiment on contaminant transport in a natural rock fracture was carried out. The scale of rock fracture was 91.5×86.5×49(cm). Mean of the aperture was 0.6mm. Uranine and cesium were used as nonsorbing and sorbing tracer, respectively. Tracer was injected along the fracture line on one fracture side as a step function and collected at the opposite side. Volumetric flow rate was 20ml/h and linear velocity was 3.71 cm/h. Channeling flow appeared dominantly due to heterogeneous aperture distribution. Channeling flow was the main source of hydraulic dispersion. Breakthrough curves were analyzed with an analytical solution. Sorption onto the fracture surface was the most important retarding mechanism in the contaminant migration. Simulated results did not respond sensitively to diffusion into the rock matrix at the flow rate of 20ml/h.

Migration Rock Fracture Dispersion Sorption Diffusion Retardation

Tsang YW, Tsang TS, Neretnieks I, Moreno L, Water Resour. Res., 24(12), 2049 (1988)
Moreno L, Neretnieks I, J. Contaminant Hydrology, 13, 49 (1993) 
NEA: the International INTRAVAL Project to Study Validation of Geosphere Transport Models for Performance Assessment, NEA, OECD (1993)
Eriksen T, Nucl. Technol., 70, 261 (1985)
Cliffe K, Gilling D, Jefferies N, Lineham T, J. Contaminant Hydrology, 13, 73 (1993) 
Park CK, Hahn PS, Vandergraaf TT, J. Contaminant Hydrology, 17 (1997)
Park CK, Keum DK, Hahn PS, Korean J. Chem. Eng., 12(4), 428 (1995)
Vandergraaf TT, Park CK, Drew D, Proceedings of the 5th International High Level Radioactive Waste Management Conference, ASCE, Las Vegas, May (1994)
Vandergraaf TT, Park CK, Drew D, Radionuclide Migration Experiments in a Natural Fracture in Granite: a joint KAERI/NEMAC-AECL WL Project (1994)
Gureghian AB, BMI/OWTD-5 (1990)
Foglia M, Iwamoto M, Harada P, Chambre, Pigford T, UCB-NE-3335, Univ. of Cal. ANS Transactions, 33, 384 (1979)
Gureghian AB, Noronha CJ, Vandergraaf TT, Large Block Migration Experiments INTRAVAL Phase 1, Test Case 9. BMI/OWTD-7 (1990)
Park CK, Woo SI, Tanaka T, Kamiyama H, J. Nucl. Sci. Technol., 29, 1184 (1992)
Park CK, Park HW, Woo SI, J. Nucl. Sci. Technol., 29, 786 (1992)
Crank J, "The Mathematics of Diffusion," 2nd ed., Clarendon Press, Oxford (1975)