Update:April 1, 2010

1) System of countermeasures at the pollution-generating source

4,COUNTERMEASURES AT POLLUTION-GENERATING SOURCE

After the court's decision on the itai-itai disease, countermeasures taken at the pollution-generating source were promoted as the starting point of the "Pollution Prevention Agreement" concluded in 1972 between Mitsui Mining and Smelting and the victims. The agreement recognized the right of victims to gather information and obliged Mitsui Mining and Smelting to disclose this information. It specified the following;

• (1)When local residents deemed it necessary, they, in the accompany of appointed experts, could at many time perform witness on-site inspections and collect technical data on end waste water treatment systems and solid waste sedimentation sites at Mitsui Mining and Smelting.
  
• (2)Mitsui Mining and Smelting would be responsible for providing local residents with technical data on equipment changes and pollution.
  
• (3)Mitsui Mining and Smelting would bear the expenses of the above. Based on this agreement, the victims and experts carried out on-site inspections, form which the following 4 problems were generalized,
  • (a)Approximately 35 kg of cadmium was being discharged into the Jinzu River per day.
    
  • (b)Approximately 5 kg of cadmium was being discharged into the atmosphere per day.
    
  • (c)It was difficult to consider these values accurate.
    
  • (d)Abandoned wells, waste heaps and areas along old railway lines were sources of contamination.
    

Though these problems were somewhat generalized, thorough countermeasures at the pollution generating source were needed. Professional investigative research was deemed necessary towards grasping a clear picture of the situation surrounding these problems, Therefore, starting in 1974, universities were asked to investigates the following 5 points,

• (1)Waste Water (Kyoto University)
  Investigative research into countermeasures against waste water discharged from the Kamioka Mines.
  
• (2)Exhaust gas (Nagoya University)
  Investigative research into countermeasures against waste gas exhausted from the Kamioka Mines.
  
• (3)Material balance (Tokyo University)
  Research into the material balance of cadmium at the Kamioka Mines.
  
• (4)Jinzu River (Toyama University)
  Research into heavy metal deposits and discharge in the Jinzu River,
  
• (5)Disposal sites (Tokyo University)
  Investigative research into the structural safety of sedimentation sites operated by the Kamioka Mines.
  

Results from studies were fed back to victims and used to propose necessary countermeasures to Mitsui Mining and Smelting.
Results were compiled into a general report on commissioned research entitled "Countermeasures against Pollution from the Kamioka Mines Following the Court Ruling on the Itai-itai Disease", and thereafter served as the basis to all pollution preventative action taken at the mines.
Futhermore, starting in 1979, the Kamiaka Mines issued a yearly report on pollution preventative action taken at the mines. By publicizing the report, a system was built whereby both the victim and the aggressor could verify and assess the effort of countermeasures against pollution taken at the source.