RAPID CITY, S.D. (KBHB) — The cave-exploring group Paha Sapa Grotto held a major on-line presentation to talk about their exploration of the huge sinkhole under the ground in a neighborhood in Black Hawk. The two huge holes that opened up two weeks ago forced the evacuation of a dozen homes.

Karl Emmanuel of Paha Sapa Grotto is with the U.S. Forest Service, but spoke on his cave expertise. He says the opening of the sinkholes at ground level was probably triggered by changing conditions inside of the underground cavern itself.

Emmanuel presented a slide show of the largest open space under the neighborhood, revealing the lack of underground support, and flooded passages that prevent a full examination of the underground structures.

The cavern is called the Hideaway Mine, after the Hideaway Hills neighborhood designation when the property was platted for development. Emmanuel called the underground void a dangerous man-made hole that should be avoided.

Homeowners and Meade County officials are looking into the possibility of last year’s flood disaster home buyback programs at this point.

The presentation can be viewed on the Paha Sapa Grotto group Facebook page.