Why they had to tear down the rest of the Champlain Tower in Surfside, Florida

 Florida mostly is sand. For example:

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Britton Hill

If you don't know about Britton Hill, Florida, you're probably not a mountain climber, and you're definitely not a highpointer. At 345 feet above mean sea level, Britton Hill is Florida's highest natural point – and the lowest "high point" in the United States.

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Discover Britton Hill: Florida's Highest Natural Point

In fact, most of Florida is between 25 and 75 feet above Sea level and was created by storms like Hurricanes over thousands and thousands of years. 

So, most of Florida resembles more a Sand Coral Atoll like you might find somewhere in the Pacific Ocean IF it was connected to Georgia and was a very long sand coral Atoll the size of Florida.

Because most of Florida is like a beach Sand Dune mostly, water when underground (even if the sand most buildings are built on are packed sand under the foundations. But, here's the problem: Sand moves with underground water currents and sometimes creates sinkholes when this happens.

Champlain tower in Surfside was sitting at this point at least on a sinkhole which weakened the foundations. Then a few days before the initial collapse water from the swimming pool was draining through cracks somewhere into the underground Garage. This was noted by engineers but they didn't know where exactly the water was coming from. So, it could have been draining from the swimming pool or other underground rivers or streams or rivulets that were moving the sand that created the sinkhole that the swimming pool fell into just before the first collapse of the terraces. One lady was talking to her husband about the swimming pool below her falling into a sinkhole when the collapse happened and she died (she was talking to her husband on the phone when she died).

So, needless to say Florida officials aren't saying much about the sinkhole that caused the collapse simply because sinkholes in Florida are sort of like Earthquakes in California. In other words "They happen all the time."

So, talking about it keeps some people from coming and buying properties in Florida just like Talking about Earthquakes in California might do the same.

So, this is why you haven't heard to much about the real cause of all the deaths. It was caused by a sinkhole that ate the swimming pool first which undermined the foundation enough to cause the initial collapse.