“It is totally incomprehensible to me that despite all of these deficiencies Gorleben is still being examined for its suitability as a storage facility, and not any alternative sites,” geologist Klaus Duphorn said.
According to Duphorn, there would have to be no gas above a depth of 1,500 metres in the salt dome, but this could “hardly” be confirmed, he said.
East German files from 1969, when the communist regime drilled into the salt dome just over the border from Gorleben in Lower Saxony, show that there was a deadly accident involving a gas explosion some five kilometres from where the nuclear waste is located.
That incident proves that there are two geological layers under the mine that hold natural gas, Duphorn said.
“This gas is highly explosive. The ignition point is at 20 degrees Celsius if it meets oxygen,” he warned.
Other geological deficiencies mean that caverns could shift, creating cracks that might allow for the contamination of groundwater, he said.
Duphorn, 76, was the first official geologist hired by the German government to survey Gorleben. His opinion, however, was later kept out of the official appraisal, he said, alleging this was because of his unfavourable conclusions.
Despite repeated allegations about questionable safety conditions and illegal development at Gorleben, exploration of the site is set to resume in October after a 10-year hiatus.
In March a media report said that Environment Minister Norbert Röttgen was considering stripping the Federal Office for Radiation Protection (BfS) of its nuclear waste duties in order to end the moratorium on new exploration and expedite further storage at the site.
Nuclear energy is deeply unpopular in Germany and protests are often staged at Gorleben, which has come to symbolise activists' concerns about its safety.