Many requirements must be fulfilled.
Disposal facility might destroyed when magma reaches repository. Even if magma doesn’t reach there, the high heat might degrade the barrier. pH value of groundwater may decrease because of the effect of the volcano and the barrier might be infuluenced.
Condition:
○Magma instusion and eruption to the land surface
・Within 15 kilometers from the center of Quaternary volcano
・Range of caldera with more than 15 kilometers active range of Quaternary volcano
○Effect of high temperature
Range of geothermal gradient doesn’t exceed 15 degrees/100 meters
○Chemical effect
Less than pH4.8 or more than 0.5mol/L of carbon dioxide concentration, as a characteristics of groundwater
The possibility of impact to the barrier due to deformation of the strata and the possibility of groundwater flowing into the disposal site due to displacement of the fault and the possibility of rapid migration of radioactive waste flowing out
Requirements:
○ A range with a width of about one hundredth of the fault length (activity segment) (sum of both sides of the fault) as a fracture zone in the active layer
○ A range with a width of about 1/100 of the fault length (the length of the fault zone) (total of both sides of the fault) as a fracture zone in the active layer
Human in radioactive nuclear waste by uplifting of underground facilities or been errode the surface.
Requirements:
○The area of over 300 meters erosion amount considering sea level change and uplifting in the future. (max uplift rate: over 90m/100 thousand years)
Because future generation may accidentally excavate radioactive waste by exploration and mining of natural resources.ining of mining resources.
Requirements:
○Minerals specified in the Mining Law, should not exist according to the nation-wide literature information. (However, within the area there is a range where the presence of minerals has not been confirmed and it is necessary to be confirmed by investigation.)
Because it is preferrable for transportation.
Requirements:
○Range around 20 km from the coast (excluding places over 1,500 m above sea level)