A fresh nuclear test at North Korea’s mountainous testing site could trigger a leak of radioactive material, South Korea’s chief meteorologist has warned.A hollow space of up to 100m in length in the bottom of Mount Mantap could implode, Nam Jae-cheol said. Pyongyang’s last nuclear test in early September 2017 appeared to have triggered several landslides.

North Korea has conducted six nuclear tests since 2006, using the same site test each time.  “There is a hollow space, which measures about 60 to 100 metres in length, at the bottom of Mount Mantap in the Punggye-ri site,” Mr Nam was quoted by South Korean news agency Yonhap as saying.”Should another nuke test occur, there is the possibility of a collapse,” he warned.  The Punggye-ri test site, situated in mountainous terrain in the north-east of the country, is thought to be Pyongyang’s main nuclear facility and the only active nuclear testing site in the world.

Hong Kong’s South China Morning Post newspaper reported on October 27, 2017 that Chinese geologists warned North Korean officials after the September 2017 test that additional tests there could lead to a massive collapse and a leak of radioactive waste…

Pyongyang might soon launch a satellite – widely seen as a test of the country’s ballistic missile technology.

Excerpts from North Korea: Fresh test could trigger radioactive leak, South says, BBC, Oct. 2017