Simplify the following text for a Grade 4 native English-speaking person.
Original: The Flaming Gorge Dam is a concrete-arch dam on the Green River in Utah , in the United States . Built in 1958-1964 , the dam is 502 f tall , 1180 f long , and 131 f thick .
Simplified: The Flaming Gorge Dam is 502 f high above the Green River .