"The dozer is preferable to a back-hoe or even tractor with a box blade because it can be so effective at packing clay by running the tracks back and forth over the subject area....."
Meadowlark,
Dozers are actually low ground pressure machines, designed to be able to get around in soft ground conditions where a wheeled vehicle can't. For instance I have a Cat D5 which weighs about 25,500 as it is configured, but since it has about 3800 in^2 of track area in contact with the ground, it only exerts a ground pressure of about 6.7 psi. That is an average pressure of course. On the other hand I have an international cub tractor which weighs about 1950 with the wheel weights on. However it only has about 58 in^2 of contact with the ground over all 4 wheels. This equates to 33 psi which means that my little tractor exerts almost 5 times as much pressure as my considerably larger dozer. Appearances can be decieving. I'd run a sheepsfoot over the worst areas. A sheepsfoot can pack at around 250-300 psi. Don't use a sheepsfoot over a bentonite liner however. Just my $.02 from an engineer's perspective.
