No, the park you are thinking of is Kircher Park. It went in last fall in Eureka.
Unger Park is in Fenton behind the Soccer Park and was approved for an 18 hole course with the possibility of another 18 in the near future. GDS did the course design (supposedly a Champ 18 course similar to Foundation Park) and RCF had begun clearing the land when the Meramec River went over it's banks this spring and flooded the park. It has been underwater and closed to the public ever since. Anybody who remembers the Creve Coeur Lake Park disaster of 1993 can understand that hopes are not high in St. Louis that Unger Park will ever materialize as a disc golf course site at this point.