Text size
Yellow text on a blue background
Black text on a yellow background
Yellow text on a black background


  • Enquiries
  • Site map

For the future of the Earth

Home > Outline of Japan's Industrial Pollution Abatement > Preventative Measures Against Water Pollution Jinzu River, Toyama Prefecture > 4) Countermeasures against abandoned shafts and waste heaps

Main content starts here.

Update:April 1, 2010

4) Countermeasures against abandoned shafts and waste heaps


Abandoned shafts and waste heaps can be contaminated with cadmium through contact with spring water, retained water and rain water. As means for preventing contamination by heavy metals, the Special Measures Law concerning Countermeasures against Mining Pollution was enacted, Contamination from runoff was prevented by sealing shafts, shutting off air passages and neutralization, while water quality was improved and surface penetration of rain water was controlled. To prevent soil contamination and scattering debris in waste heaps, it was made mandatory to cover over and plant vegetation on top of waste heaps and barren land .
From 1973 to 1992, the Kamioka Mines spent about 5.5 billion yen in furnishing equipment ordered under this law, and took measures to prevent contamination of abandoned shafts and heaps. This included approximately 21 hectares of grass planted land, 51 hectares of afforested land, 2,400 m2 of covered land, 7,800 m2 of asphalted surface, 560m of dividing walls, and 970m of water way improvement and extension work.