KUMAMOTO — The Kumamoto Prefectural Government began work Aug. 21 to remove nets from the mouth of Minamata Bay, put in place more than two decades ago to prevent mercury-contaminated fish from leaving the bay and spreading disease.
The approximately 70 million yen net-removal project, expected to be completed by the end of September, began after Kumamoto Gov. Joji Fukushima declared last month that fish in the bay are no longer contaminated with mercury and, therefore, safe to eat.
The Minamata Fishery Cooperatives agreed to the plan to remove the net and work began near Koiji Island.
The cost of the removal will be shared evenly by the prefectural government and Chisso Corp., which began dumping untreated factory waste water into the bay in 1932. In 1968, the government concluded that waste from Chisso’s plant had caused the outbreak of a disease that was later named Minamata.
For more than two decades, the net across the bay has symbolized the tragedy of the mercury poisoning disease.
The fishermen’s cooperative has already decided to lift its self-imposed ban on fishing inside the bay after the nets are removed.
Fish caught in the bay have been collected and burned by Chisso. With the opening of the bay, subsequent yields will probably go on the market, starting in October.
Some 10 workers aboard a crane ship, one of three vessels mobilized for the removal Aug. 21, brought up sections of the nets and folded them.
The nets once extended a total length of 4,400 meters, each net measuring 30 meters in length. Officials estimate that all the nets will be removed within five days, and then anchors that hold the nets to the seabed will be removed in about one month.
The nets were lowered by the prefectural government after concern about mercury-contaminated fish gripped the entire nation.
Work to remove the net comes after mercury concentration levels in all the bay’s fish species, checked periodically by authorities, fell below danger levels set by the central government in 1995.
Gov. Fukushima declared on June 29 that fish and shellfish in the bay are all safe for human consumption.
The fishermen’s cooperative held an extraordinary general meeting Aug. 18 and decided to consent to the removal of the remaining nets.
Jun Tsuji, 35, a Minamata fisherman who oversaw the work to remove the nets from aboard his boat, said it is a ceremony to mark the end of an era.
Tsuji said the bay has been safe for some time, but whether any fish remain is another matter.
Minamata Bay is no longer the fishing ground it once was because shorelines have changed as a result of reclamation, he said.
Tsuji, who now fishes off Amakusa, Nagasaki Prefecture, said he had no intention of fishing in Minamata Bay.