About 603, it is in Songsan-myeon, a different administrative division of Hwaseong, while neighbouring 1134 is just down the highway in Mado-myeon, also part of Hwaseong. There are no tower sites in Namyang (it's all part of the city of Hwaseong and Koreans would call all those locations "Hwaseong" if talking to another person or describing where they reside), and while it is awfully close to both tower sites, I'm not sure who has listed it as such or perhaps if many years ago there was a consolidation, though it would be quite highly unlikely for an -eup (town) to downgrade its land to a -myeon (rural township). Hwaseong is the largest city in the country I believe, and "city" in China and Korea is more like "county" in North America actually, so there are some differences when reporting locations to start with.