The sixth-tallest building in the world is being built in Seoul, South Korea, but a strange geological phenomenon is threatening the site, leaving the construction team baffled as it gets closer to finishing it.
The AP reports that a bunch of strange, small sinkholes are popping up out of nowhere in neighborhoods nearby.
The Korea Times tweeted a picture of one of the sinkholes back on July 21:
— The Korea Times (@koreatimes1) July 21, 2014
These strange earthly issues are causing safety concerns, threatening the construction. The AP says that 70 of 123 floors have been built, but now locals living in residential neighborhoods nearby have started seeing sinkholes on their roads and became very worried.
So far, at least one official at the skyscraper's construction company, Lotte Moolsan, is claiming that the sinkholes are too far away to be caused by the construction, according to the AP.
Sinkholes are often caused by groundwater and erosion. The USGS describes them as " an area of ground that has no natural external surface drainage — when it rains, all of the water stays inside the sinkhole and typically drains into the subsurface. Sinkholes can vary from a few feet to hundreds of acres and from less than 1 to more than 100 feet deep."
On top of that, a lake that the tower overlooks seems to be getting smaller, and nobody knows why that's happening either. Lotte Moolsan says they're pumping water into the lake to keep the levels up. It's dropped from about 16 feet to 14 feet.
When it's completed, the tower is set to be just a little taller than One World Trade Center in Manhattan.
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