Neat video, and it looks like it was a pretty park.
Any evidence for the story about the person being flung off the coaster onto the highway. I've heard apocryphal versions of the same story attached to a few different parks, but never any evidence for any of them actually happening. And couldn't find any stories or evidence of any roller coaster incidents at Springlake either. it makes me wonder if it's another of the horror stories that got passed around that everyone believed but never actually happened.