Appendix C
Construction Quality Assurance Monitoring Techniques
TABLE C.1 CQA Techniques for End-of-Construction Barrier Element Integrity
Barrier Element |
CQA Integrity Monitoring Techniques |
Compacted low-permeability soil |
In situ density and water content testing; in situ hydraulic conductivity testing using infiltrometers, pan lysimeters, and borehole permeameters; physical sampling and laboratory testing for index properties and saturated hydraulic conductivity |
Evapotranspirative cover soil |
In situ water content testing; in situ flux rate testing using pan lysimeters; physical sampling and laboratory testing for index properties, including saturated hydraulic conductivity, and for the soil water characteristic curve |
Geomembranes |
Nondestructive seam testing; physical sampling and laboratory testing of seams; electrical leak detection testing; interface shear testing |
Geosynthetic clay liners |
Physical sampling and testing for bentonite unit weight and saturated hydraulic conductivity; interface shear testing |
Soil-bentonite walls |
Sounding of the trench prior to backfill placement, physical sampling, and testing backfill soil from the borrow pit for saturated hydraulic conductivity; physical sampling and testing backfill soil from the wall for saturated hydraulic conductivity; in situ saturated hydraulic conductivity testing of the wall backfill |
Cement-bentonite walls |
Sounding of the trench prior to backfill placement, physical sampling and testing of the cement-bentonite backfill for saturated hydraulic conductivity; physical sampling and testing of cores from the wall for saturated hydraulic conductivity |
Soil-mixed walls |
Physical sampling and testing of cores from the wall for saturated hydraulic conductivity |