Groundbreaking news out of the seashore last week: a three-foot by three-foot sinkhole was discovered on Sir Francis Drake Boulevard, a few yards from the intersection with Pierce Point Road, early Friday morning. Road crews inspecting the pancake-shaped hole unearthed a busted culvert beneath the road surface, the likely culprit in the collapse. The underground cavern, about 20 feet long and five feet deep, was cleared of rocks and materials to allow the Department of…