Wind tower pilings and piling caps

When the crew had the pilings dug for the house, we also had them dig and pour five pilings for the wind generator tower. However, we did not have the hardware for the top of the pilings at that time, so they did not pour the top three feet. The plan was to pour the piling caps when they built the dome.
Unfortunately, when they came back to build the dome, there was a concrete shortage and the weather had turned cold, too cold to pour concrete outside without heating it, so they left it for us to do in the spring. This turned out to be a bigger task than expected. Gophers has piled quite a bit of dirt on the existing pilings, so a quite a bit of preparation was needed before we could have the piling caps poured. We finally had them poured at the beginning of July. The picture on the bottom is one of the four pilings that would secure the guy wires. The picture on the top is the center piling that would secure the 70 foot tower.

When we were first planning the installation of the tower we read through the manual and realized that the pilings recommended were not sufficiently deep to go below our 6 ft frost line. Most water pipes here are 8 ft deep. The engineer for the house agreed they were not adequate and recommended we use the 18" diameter 25ft deep pilings that were used in the house. We recommend that local engineers be consulted for all installations.