$[35$ points$]$ You are the design engineer of record for an industrial manufacturing building that is being constructed near the Golden Triangle Regional Airport. You have decided, to maintain proper site drainage and to ensure the building meets appropriate flood ordinances, the building will be constructed on top of a $6-$ft thick fill pad having plan dimensions of $350$ feet by $220$ feet Your specifications for the fill require that it meet the material requirements for an $"$SC$"$ or $"$CL$"$ soil, when classified according to the Unified Soil Classification System. Your specifications further require that the material be compacted to a relative compaction equal to $98\%$ of the maximum dry density determined in accordance with a Standard Proctor compaction test. Finally, your specifications require that at least one field compaction test be performed for every $500y{d}^3$ of compacted material.

The contractor for the project has submitted soil samples from four proposed borrow pits $($named Borrow Pits $"$A$"$ through $"$D$"),$ and has asked you to indicate which of these soil samples would be acceptable to use on the project. For one of the soils that you approve,

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the contractor intends to excavate the material from the borrow pit, truck it to the site, add$/$subtract water as necessary, place it in the building pad, and compact it to your specifications. He has provided test results for each soil sample, on the following pages.

Select all that are acceptable: A B C D

Using ONE of the acceptable soil samples $($any ONE of your choosing$),$ complete the following:

b$)$ What is the percent saturation of the soil in$-$situ, $($at the borrow pit, prior to its excavation$)?"$In$-$situ" means $"$as it sits in the ground."

c$)$ What field dry density would correspond to the minimum dry density that would be acceptable, according to your specifications? Express your answer in pcf$.$

d$)$ Assuming the contractor compacts the soil at EXACTLY the maximum dry density and at the optimum water content, how much soil will the contractor need to excavate from the borrow pit to construct the building pad? Express your answer in $y{d}^3.$

e$)$ How many field density tests do you recommend be performed for each lift of construction to ensure the quality of compaction being provided by the contractor? Round the number up to the nearest integer value.

f$)$ If a randomly placed field density test on one of the lifts reveals the compacted soil has a dry unit weight of $101pcf$ and a water content of $15$ percent, will you accept the contractor's work on that lift, or will you re$-$perform the field density test, or will you reject the contractor's work on that lift? Indicate by stating "ACCEPT", or "RETEST", or "REJECT."