During a soils investigation, a clay layer was first encountered at a depth of $2$ feet and found to have a thickness of $20$ fect. The SM $-$ Silty SAND soils above this clay have an average unit weight of $115$ pef. Ground water table is $3$ feet below surface. An undisturbed sample was taken at a depth of $25$ to $27$ fect and a consolidation test was performed on it: Below the elay is a SW $-$ Well graded SAND starting at $35$ feet depth. Initial measurements and test results are presentod below:

Consolidation Test Sample:

Initial Sample Height $=0\mathrm{.}500$ in

Sample Diameter $-2\mathrm{.}50$ in

Sample Weight $=72\mathrm{.}8g.($inithat weight of solids and water$)$

Specific Gravity $-2\mathrm{.}70$

Initial Water Content $=37\mathrm{.}2\%$

Sample was double$-$drainod.

For the $90\%$ consolidation data find:

$1.$ Determine the maximum past effective stress

$2.$ Construct the field consolidation curve