What is the vadose zone in an area’s subsurface region, and what is the explanation for the condition?

1.In an oedometer test a specimen of saturated clay 19 mm thick reaches 50%consolidation in 20 min. How long would it take a layer of this clay 5 m thick toreach the same degree of consolidation under the same stress and drainageconditions? How long would it take the layer to reach 30% consolidation?

a) Calculate the OCR and OCM for the midpoint of the clay layerprior to fill placement. b) Calculate the settlement for the clay layer in the soil profile shown in problem 3, exceptassume the clay is normally consolidated. c) Calculate the settlement for the clay layer in the soil profile shown in problem 3, exceptassume the clay has a preconsolidation stress of 1800 psf. d) Assume the time to primary consolidation is 15 years,and the design life of the project is 50 years. What will the secondary compression of the claylayer be? Answers3 1.45 ina) OCR = 4.06 OCM = 3014.8 lb/ft2b) 6.0 inc) 3.53 ind) 0.79 in

Explain the difference between a soil stratum that is an aquifer and one that is an aquitard.