Complex sentence: At the same time another fracture appeared in a corresponding position on the eastern portion of the dam, starting at the crest near the last spillway section and running downward at an angle for sixty-five feet before ending at the hillside.
Split into simpler sentences: At the same time another fracture appeared in a corresponding position on the eastern portion of the dam. This fracture started at the crest, near the last spillway section and ran downward, at an angle, ending sixty-five feet below, where it reached the hillside.