Prior to about 1975, grout was required to be placed between the illumination pole base plates and concrete foundations. Since then, it has been determined that such grout placement under pole or sign bridge base plates causes moisture to become trapped. This, in turn, contributes to excessive corrosion of the pole, support, base plate, anchor bolts, nuts, and other appurtenances.

It is imperative, therefore, that this grout be removed from under existing poles and not placed under newly installed poles. Anchor bolts should then be cleaned and painted with zinc rich paint. If severe deterioration is discovered, a more detailed investigation should be made into the remaining strength of the bolts.