Thanks again for the insights.

They noticed the gravel areas on thursday sand spent Friday working in the good clay. I will need to talk wit the team tomorrow about how we go forward, and we are likely to get a clear picture of the full extent of the issue in a couple days.

Snipe, you are suggesting 3 lifts of 6-8" instead of 2, that seems a safer bet in any case.

teehjaeh, if we get 3 good lifts, do we need the polymer or are you thinking of that as an insurance policy? I'll know better this week, but that would seem to depend on the total area where we cut through the clay and into the gravel below. I am hoping that we can keep that to a minimum and not have broad areas to cap. But, we will see this week, and then polymer, (or Bentonite) would seem like good insurance.

FishinRod, good comments as usual. I think a deviation from initial plan is needed to avoid cutting into the gravel in that area. When I said it wouldn't necessarily pass the pencil test it was because of the size of some of the gravel, not the general amount. The soil is variable, as you said, but I successfully made some pencils, while at other times my rolling of the clay is limited by the aggregate size. When I have some gravel the size of a pencil diameter in even 50% clay, then it tends to be a weak link and limits my "pencil."

I am hoping we can agree on a plan of action tomorrow.

Thanks again!