It is not a surprise this park is closed. It IS amazing that the park was open from 1978-1996.
Action Park was often referred to as "Class Action Park" and "Traction Park" due to the injuries.
On the Tarzan Swing, you either let go to land in the water, or you would swing back into the crowd. Or worse yet, you'd land in the woods.
The Alpine Slide was a concrete slide down the side of a mountain. You would ride it on a little cart with a hand brake. When an employee died after flying off the slide and hitting his head on a rock, it was determined the rock killed him and not the slide.
"Ride At Your Own Risk" was the motto of the park.
After five deaths, many broken bones, various concussions and tons of other injuries, the park finally closed in 1996 ... due to financial problems. Safety had little to do with it.
Here is the commercial for the park. Notice the people shooting out of the cannon slide. Also, watch for the full speed golf carts, 360 degree slide and Alpine Slide.
You can read all about it here: Traumatic License: An Oral History of Action Park
Here is a quick documentary about it: