TY - GEN
T1 - Mineral barriers against natural contamination from excavated rocks
AU - Naka, Angelica
AU - Katsumi, Takeshi
AU - Flores, Giancarlo
AU - Inui, Toru
AU - Takai, Atsushi
AU - Ohta, Takehiro
PY - 2012
Y1 - 2012
N2 - The barrier performance of Geosynthetic Clay Liners (GCL) containing Na-bentonite, zeolite (clinoptilolite), and ferrihydrate permeated with artificial Acid Rock Drainage (ARD) are reported in this study based on hydraulic conductivity tests. The hydraulic conductivity of GCL permeated with distilled water was 1.4 ×?10-11m/s and it increased by one order of magnitude when permeated with ARD. The hydraulic conductivity of zeolite permeated with water was 3.0 ×?10-10m/s and it increased 10 times when it was permeated with ARD. The hydraulic conductivity of ferrihydrate was 7.3 ×?10-9m/s for water permeation and this value remained constant after ARD permeation. Through chemical effluent analysis, it was observed that metals and metalloids (Fe, Al, Zn, Cu, Pb, and As) start leaching out the system after 5 to 10 pore volumes of flow (PVF). The metal retention order differed for each mineral. For bentonite it was Cu ≈ Al >As >> Pb >> Fe > Zn, while for zeolite, Al ≈ Cu > As > Fe > Zn > Pb, and for ferrihydrate, As > Al > Cu > Fe > Pb ≈ Zn. These three minerals appear to be good candidates for ARD treatment.
AB - The barrier performance of Geosynthetic Clay Liners (GCL) containing Na-bentonite, zeolite (clinoptilolite), and ferrihydrate permeated with artificial Acid Rock Drainage (ARD) are reported in this study based on hydraulic conductivity tests. The hydraulic conductivity of GCL permeated with distilled water was 1.4 ×?10-11m/s and it increased by one order of magnitude when permeated with ARD. The hydraulic conductivity of zeolite permeated with water was 3.0 ×?10-10m/s and it increased 10 times when it was permeated with ARD. The hydraulic conductivity of ferrihydrate was 7.3 ×?10-9m/s for water permeation and this value remained constant after ARD permeation. Through chemical effluent analysis, it was observed that metals and metalloids (Fe, Al, Zn, Cu, Pb, and As) start leaching out the system after 5 to 10 pore volumes of flow (PVF). The metal retention order differed for each mineral. For bentonite it was Cu ≈ Al >As >> Pb >> Fe > Zn, while for zeolite, Al ≈ Cu > As > Fe > Zn > Pb, and for ferrihydrate, As > Al > Cu > Fe > Pb ≈ Zn. These three minerals appear to be good candidates for ARD treatment.
UR - http://www.scopus.com/inward/record.url?scp=84867469996&partnerID=8YFLogxK
U2 - 10.1201/b12754-144
DO - 10.1201/b12754-144
M3 - Conference contribution
AN - SCOPUS:84867469996
SN - 9780415621359
T3 - Advances in Transportation Geotechnics II - Proceedings of the 2nd International Conference on Transportation Geotechnics, ICTG 2012
SP - 924
EP - 929
BT - Advances in Transportation Geotechnics II - Proceedings of the 2nd International Conference on Transportation Geotechnics, ICTG 2012
PB - Taylor and Francis - Balkema
T2 - 2nd International Conference on Transportation Geotechnics, ICTG 2012
Y2 - 10 September 2012 through 12 September 2012
ER -