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VII. Copper-poisoning issues and their aftermath

1. From Copper Poisoning to Flood Prevention

In the processes involved in Japan's development as a capitalistic nation, the Ashio copper-mine poisoning incident became a central social issue, but once Japan was involved in the Russo-Japanese War the farmers" movement experienced a significant setback. After the war, when Japanese capitalism took on an imperialistic bent, Yanaka Village was demolished and used as poisoned water catchment basin. Thus the problem was downgraded as a social issue, but the damage from the poisons was not eliminated. This is because, in the Ashio mine situation, no effective measures were taken against poisons which caused environmental destruction over a very wide area, and the responsibility for improving the situation came to rest solely with the farmers; even the compensation made by the copper company was not official. What meaning, then, can we derive from the mass movements of the farmers? The farmers who lived in the poisoned areas along the Watarase River hardly benefitted from them. However, the movement did draw public attention to the environmental problems, and had a great influence on the management of the copper-smelting smoke problems common to all the copper mines in Japan.

The construction of a dam at the site of Yanaka Village caused a conflict of interest between the farmers who lived in the upper regions of the Watarase River and those living in the lower regions where the Watarase and Tone Rivers meet. The government was pressing for a solution to the poisons problem that would involve flood control and would necessitate the demolition of Yanaka Village and the surrounding areas through the construction of a dam and a catchment basin. Under pressure from the government and the intense social climate brought about by the Russo-Japanese War, the farmers along the upper reaches of the Watarase River, except those in and around Yanaka Village, accepted the government's plans for flood prevention and catchment basin construction projects. In this manner, the problem of copper-mine-induced poisonings was glossed over and concern was directed toward the containment of floods. Sixteen families continued to live in and around Yanaka Village and, although their lives were extremely difficult, they struggled for the restoration of the village by continuing their lawsuit over the price to be paid for their land. However, in 1917, the struggle ended in acceptance of the proposal made by Tochigi Prefecture. In September of the previous year, Shozo Tanaka, leader of the farmers' struggle, died at the age of 72. Tanaka's followers built a shrine in memory of his struggle, and this remains as a symbol of his and his followers" continuing protest movement.

With this metamorphosis of the copper-mining poisons problem into a problem of flood control, the majority of farmers had great hopes for the flood-control improvements to be carried out on the Watarase Rive. The work was started in 1910 and was completed in 1927, at a cost of 12 million yen. Soon after this construction project had been started the farmers became aware of the fact that the mine-poisons problem had not been solved, and was in fact continuing. After the project had been finished, it was noted that there had been no improvement in the situation in regard to the poisons in the water. The reason for this was all too clear, for the Ashio copper mine remained a very intractable source of pollution and environmental destruction over the entire Watarase river basin. Although a sedimentation catchment basin and slag-retention areas had been provided, the size of the pollution-prevention construction was too small and the functions provided by the control facilities were limited to make any meaningful difference to the poisons brought by the natural water systems. This was because the refinery smoke had denuded the mountains, which, as a result, were unable to retain rainwater. Thus the water of the river rose with the coming of the rains, while it was low after a spell of fine weather. The farmers who made use of the river water for irrigation were troubled by floods and droughts; with the floods, the poisons were spread over extensive farming areas. In order to deal with these new problems, the farmers had to come up with their own unique forms of irrigation and their own water-system infrastructures. They made requests to the mining company for donations through which these poison-prevention systems could be built, but most expenses had to be covered by their own funds or a limited supply of government funds. The problem of copper-mining poisons was never solved, but simply became latent. In order to rid the irrigation system of the poisons, it was necessary for each farmer to construct his own poisons sedimentation pond at the location of the water input from the river. The farmers made every effort to rejuvenate the poisoned land, but Furukawa only supplied a small amount of lime for these purposes whenever the farmers became angry over the problem and demanded help. The Ashio copper-mining company never provided formal compensation for the excessive damage done, even after the Second World War.

Although the flood-prevention construction had been completed, the Watarase river basin was flooded again and again by high water, and each time new plans were made. In 1947 damage caused by typhoon Katherin extended from the central reaches of the river basin all the way to Tokyo. Because of this devastation, dozens of billions of yen were invested in flood-control projects.1

2. Recurrence of the Copper-poisons Issue

Even though the copper-mine poisoning problem continued to be an issue for several decades, Furukawa indicated as early as 1897 that the company would take no responsibility for the damage done after the poison-protection construction had been completed, and that any remaining problems relative to poisons found in the natural environment were a result of inadequacies of method left over from mining activities in the Tokugawa period. In this desperate situation, the farmers had no recourse but to ask for lime and a small amount of compensation from the mining company. But on 30 May 1958, the sudden destruction of the poisons-retention basin at Gengorozawa revealed the seriousness of the mining poisons problem.

After bringing an apparent end to the poisons issue through the total demolition of Yanaka Village for a catchment basin, Furukawa began to extend its activities into various fields such as banking and electric wire and rubber production. In the booming economy of the Second World War, the Furukawa Company was turned into a corporation, but mismanagement in the general business section led to the closing of the bank and a decline in business. From the Manchuria Incident onward to the Sino-Japanese War and into the Second World War, the Furukawa Corporation's industrial section grew very rapidly. The Furukawa zaibatsu, unlike the other zaibatsu, was not dissolved by the occupation forces after the end of the war, but the Furukawa copper mine was forced to become an independent company. Production from the mine declined in the last years of the war, reaching its bottom during the period immediately after the war because of the economic recession and a lack of materials. But when new mining technologies were introduced during the Korean War, the Ashio mine's production rose and the mine once again moved into high-gear production. In 1955, the company imported a refining method from Finland which was able to oxidize the sulphur in the ore, and with the higher concentrations of sulphurous acid gas it became much easier to produce sulphuric acid from it. Through the application of this imported technology, the environment was, at long last, protected to a more meaningful degree from the ravages of the sulphurous acid gas, but it took another 20 years before there was complete relief from the damage produced by the refinery smoke. With the new refining method brought on line, attention was focused again on the problem of copper-mining poisons. During this period, Japan was again entering on a period of high economic growth and her production capacity reached pre-war levels.

The Gengorozawa poisons retention basin was constructed in 1943. This was one of 14 slag-pile retention basins, a little smaller than the others.

When the basin burst its seams, the weather was fine, so the responsibility for the destruction rested very clearly with Furukawa's mismanagement. About 2,000 cubic metres of slag were flooded and three railway lines belonging to Japan National Railways were washed with the slag into the Watarase River. When heavy rains fell in Ashio, the farmers made it a rule to close irrigation system inlets from the river, but at the time of the accident all the irrigation inlets were open because there had just been a spell of good weather and because it was just before rice-planting time. Thus the poison-laden slag was washed into 6,000 hectares of rice-fields immediately before planting time. Over 25,000 farmers in Morita Village (now Ota City), Yamada-gun, Gunma Prefecture, were once again faced with the intractable problem of a poisoned agricultural environment. Led by Shoichi Onda, chairman of the Agricultural Co-operative Association, a new farmers' protest sprang up against the Ashio copper mine. Onda emphasized the importance of the farmers not accepting token payments from Furukawa, as they had in the past. In July Onda organized an association in Morita Village for the purpose of halting copper production. In August he was able to form the same kind of organization in three other cities and three provinces. Each of these three organizations allied itself with the other two and elected Onda chairman.

The monstrous slag piles, built up over a long history of mining, could be seen in many places in Japan and continue to pollute farmland, leading to many deaths. The largest slag-pile dam collapse in Japan's modern history occurred at the Okusawa mine, owned by the Mitsubishi Mining Company, on 20 November 1936. The accident caused 362 deaths and 81 serious injuries, and destroyed some 400 houses.2

Fortunately, the destruction of a slag-pile containment basin had never happened in Ashio. However, at the time of this unfortunate accident, the greatest social issue centred around pollutional discharges from the Edogawa (Edo River) Factory of the Honshu Paper Mills Company in Tokyo. Untreated water containing black sludge was being discharged into the river, destroying fishery resources in the estuary and in Tokyo Bay. Fishermen from the areas, especially Urayasu-cho, Chiba Prefecture, were opposed to the paper mill company, and approached the Tokyo Metropolitan Government and the Honshu Paper Mills Company to appeal for help. Many fishermen came into direct confrontation with the police and were arrested. After this Urayasu Incident, the government began tightening up on water-quality controls and two water-quality laws were passed. These laws had to do with the safety of water resources in public locations and with the quality of water discharged from factories. Although these legislative efforts did not really result in any substantial gains in actual preservation of water resources, they were the first such regulations laid down in Japan. The water-safety laws were passed in April 1959 and a Water Quality Inquiry Commission was established by the government to set water-quality standards for rivers and lakes in Japan.

Hundreds of farmers from the organizations against environmental pollution in the three cities and three provinces went by bus to appeal to the government for the establishment of water-quality standards and regulations for the Watarase River. At last, in 1962, the government decided to examine the Watarase River, and asked Onda to be a member of the Watarase River Inquiry Commission on the condition that he resign as chairman of the allied farmers' associations. Onda was very angry at this condition, but he nevertheless tendered his resignation. In the deliberations of the Inquiry Commission Onda insisted that the standard for copper pollutants in the water should be 0.01 ppm (parts per million = parts of pollutant per million parts of water), while the representatives of the Ministry of International Trade and Industry and the Ministry of Agriculture and Forestry were bent on setting the standard at 0.06 ppm. However, after a series of long and difficult discussions, a majority of commission members voted for the copper-pollutants standard of 0.06 ppm, and Onda's request was rejected. So the commission agreed that the pollutants' standard for the Watarase River should be 0.06 ppm on an annual average basis.

Between 1969 and 1970, many grass-roots movements against environmental destruction came to the fore. During that time poisonous metals, including arsenic, were discovered in the waters of the Watarase River when the amount of water had increased owing to heavy rains. What Onda had feared most came true. From the 1971 crop of rice harvested in the Morita Village paddies, cadmium exceeding the permissible level was found, and in January of the following year the shipment of the crop was partially halted. The Morita Village farmers' association sent a petition to the newly created Environment Agency, and asked the Environmental Dispute Coordination Commission (Kogaito Chosei Iinkai) to step in as arbitrator, on the basis of the Environmental Pollution Disputes Settlement Act (Kogai Funso Shoriho), in their negotiations with the Furukawa Mining Company for damages. The 970 members of the association, led by Meiji Itabashi, were demanding from Furukawa 3.9 billion yen (about $27 million) as compensation. The negotiations went well for the farmers, partly owing to the increasing national outcry and the growth of movements against environmental destruction.

In November 1972, while the matter was under arbitration, Furukawa suddenly announced that it was going to close the copper mine. The company maintained that the closure was due to the fact that the ore veins were exhausted, but it was seen to be not unrelated to the arbitration that was then in progress. In the following February, the Ashio copper mine was closed, and the equally old Besshi copper mine was also shut down in March. However, though the mining operation was halted, the smelting of ores still continued using imported ores. In fact, copper production at Ashio increased after the closure of the mine.

The arbitration came to an end on 11 May 1974, when both the farmers and Furukawa Mining agreed on the conditions offered by the Co-ordination Commission and signed the final document. The agreement provided that the company pay 1.55 billion yen (about $10.7 million), improve the copper wastes effluent treatment system, improve the quality of the poisoned farmland, and sign an agreement for pollution control. This was the first time in the 100-year history of the company that Furukawa actually paid money to the farmers in compensation for damage done instead of simply providing token donations from time to time. Unfortunately the negotiations went on behind closed doors, and as a result there was no national media debate about the problem, which would have strengthened the hand of other antipollution movements. These negotiation processes and the related statistics could make a valuable contribution to future attempts to protect the natural environment.

Although the copper-poison issue, which was rekindled by the bursting of the Gengorozawa catchment basin in 1958, was settled by the intervention of a government agency, people in the area are still suffering from the effects of the Ashio mine operation. The Ashio refinery is surrounded by 14 very large slag-pile accumulation basins and these are a constant menace to the natural river system, for any one of them might collapse into the river if there were heavy rains or an earthquake. Although the company insists that the poisons in these slag-piles are under constant supervision, there are small amounts of poisons seeping from them all the time, and these can be detected in the lower reaches of the river system. Still, to this day, nothing will grow on 3,000 hectares of mountain ranges around the refinery. The Ministry of Agriculture and Forestry has spent over 10 billion yen ($69 million) on the restoration of greenery in the area, but it will take several more generations and the expenditure of many more millions of yen before the regeneration of life can take place. The plan proposed in 1977 for reforestation of the area called for an estimated 130 billion yen ($900 million) in funds. However, these mountains have lost all of their topsoil from erosion and nothing but bare rocks is left. Once it has been radically destroyed, the restoration of nature is difficult in the extreme, even in a country like Japan where there is plenty of ram.

VIII. Conclusions: Lessons for today from the Ashio Copper-mine poisonings

More than 90 years have passed since the first public warnings were issued in relation to copper-mining-related environmental problems. However, there still exist today very real possibilities of disaster should one or more of the slag accumulation basins collapse and be washed or moved into the river systems. The extent of the damage caused by the smoke from the refinery can be seen in the 3,000 hectares of bare mountains surrounding the area where the Watarase and Tone Rivers meet. The vast desert in this area attests to the fact that, at the end of the nineteenth century, Japan attempted to catch up with the advanced capitalist nations of the world through policies that stressed the development of industrial capacity and military might; the deeply ravaged conditions of the once pristine forest areas around the Ashio copper mine are the result of this primary-order introduction of technologically based industrial capacity into Japan without the slightest consideration for environmental preservation. We cannot close our eyes to the fact that modern civilization has been poisoned by the materialism of the Industrial Revolution and that this is manifested in the manner in which Japan adopted modern technology and in the unprecedented environmental destruction.

Environmentally destructive production technology, in the hands of management personnel who lay more emphasis on productivity than on safety and environmental integrity, is in the ascendant in Japan. The environmental poisons that arise from today's industrial technologies are no longer detectable with human sense organs. Morever, these pollutants, which (in the case of ionizing radiation) will be present for many years to come, are expected to increase very rapidly only after the next few generations. The present condition of humanity recalls the words of Shozo Tanaka, who wrote that the remnants of human life would be destroyed by technological civilization. It is as though Tanaka were continually appealing to the people who visit his shrine, in the hope that they and the victims of environmental destruction will join forces in a worldwide movement for the survival of humanity, even though they are bogged down in the muck of a technological and materialistic civilization that seeks its own destruction. His appeal is for radical change in this and other societies which create such enduring environmental problems and which, in the process, completely suppress and deny human rights. He appeals for continued resistance against the forces of death and in support of the spirit of life.


1. For further information on copper-mining poisons after the Yanaka Village Incident, see Masuro Sugai, The Development Process of Mining Pollution at the Ashio Copper Mine (United Nations University, 1982).

2. Tsuusan Daijin Kanbo Chosa Tokeibu, Honpu kagyo no suusei 50 nenshi kaisetsu hen (1980), p. 68.


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