NOSE, Osaka Pref. -- Despite the accord reached last month to settle the nation's worst dioxin pollution, which hit this rural town, deep-rooted distrust of local authorities lingers among town residents.

According to the Osaka Prefecture-mediated agreement, Mitsui Engineering & Shipbuilding Co., which built the incinerator responsible for the pollution, and its subsidiary that engaged in its maintenance, will pay 750 million yen _ mainly to cover the cost of scrapping the incinerator and removing the contaminated soil in and around the complex.

The governments of the Osaka Prefecture towns of Nose and Toyono, which jointly run the Toyono Clean Center incinerator, will be required to dispose of the contaminated soil and other polluted materials by December 2006. They must also provide environmental testing and health checks for local residents for 20 years.

The accord also calls for the creation this month of a 15-member council-- composed of local residents, town offi-cials and academics -- to discuss enforcement of the agreements. Town residents say they can now talk to officials on equal terms.

Why did it take 28 months from the discovery of the high levels of dioxin for residents and officials to meet?

"Because town officials concealed information on the pollution and residents became suspicious of them," said independent member of the Nose Municipal Assembly Osamu Yagi, one of the people who initiated the procedure that led to the successful mediation.

Naoyuki Kumagaya, chief mediator of the prefecture's pollution examination committee, stressed the importance of information disclosure to dispel residents' distrust of the town governments and the incinerator maker.

Toyono Clean Center was built in line with Health and Welfare Ministry guidelines and started operations in 1988. It was operated by an association jointly staffed by the towns of Nose and Toyono and was nominally headed by the mayors of both towns.

After the ministry introduced a guideline on gas emissions from incinerators in January 1997, requiring dioxin concentrations to be less than 80 nanograms per cu. meter of exhaust, the two towns decided to spend around 1.5 billion yen on renovations -- higher than the plant's original construction cost of 1.1 billion yen. A nanogram is one-billionth of a gram.

Yagi said that when he asked Nose Mayor Nobutaka Tsuji during the 1997 February assembly session whether the renovation was meant to curtail dioxin emissions, Tsuji replied that the work was simply an update after its nine years in service, adding that environmental concerns were only part of the reasons for the renovations.

The renovation plan, however, was nothing more than a step to reduce dioxin emissions, he said.

"The word 'dioxin' was taboo at the town hall and the association because officials of the towns had promised that there would never be a dioxin problem for nearby residents when the plant was originally built," Yagi said.

Tsuji denies he was trying to cover up the dioxin problem. "In February 1997, we did not have the results of an emission gas test conducted in January the same year, which came out only in March," he said.

The January test showed that 180 nanograms of dioxin per cubic meter of gas were emitted from the Nose incin-erator -- well above the ministerial guideline of 80 nanograms per cubic meter.

The results, however, were not released until June 1997, when results of another emission gas test in May also showed a dioxin concentration of 150 nanograms per cubic meter. The results of both tests were not submitted to the ministry until June 1997.

Tsuji explained that incinerator officials wanted to obtain more data after the plant began operating 24 hours a day in April, with the rationale that more dioxin is generated when incinerator temperatures are low -- just after the commencement and conclusion of operations. The officials therefore reckoned that round-the-clock operations would generate less dioxin.

Residents demanded that the plant stop operating after the test results were made public. Following instructions from the prefecture, Toyono Clean Center halted operations in June 1997. At that time, however, officials of the two towns still intended to renovate the plant and resume operations.

Further tests revealed that dioxin contamination was even worse than had initially been suspected. A November 1997 study found soil in Nose High School farmland adjacent to the incinerator contained 2,700 picograms of dioxin per gram of soil. A picogram is one-trillionth of a gram.

In an April 1998 study, the soil surrounding the plant was found to contain as much as 8,500 picograms of dioxin per gram of soil and the bed of a pond near the facility registered 23,000 picograms of dioxin per gram.

In September 1998, a Health Ministry report revealed that the soil below the facility's cooling system contained 52,000 nanograms of dioxin per gram and the cooling water registered 130,000 nanograms of dioxin per liter of water. A decision to dismantle the incinerator was made in October.

Yagi demanded that Nose force the plant maker to take responsibility for the pollution from the "faulty" incinerator, but said the town could not do so because of an incident that occurred in 1992, when the prefectural government ordered the operator to take measures to reduce dioxin emissions.

In response, the operator asked a Mitsui subsidiary to estimate the cost of renovation work, which at 120 million yen was deemed too expensive for a plant that had been in operation for only four years. The association running the incinerator thus decided to forgo the renovations.

Tsuji, however, said the 1992 decision did not affect the town's attitude toward Mitsui's responsibility after the contamination was reported in 1997.

"Because the plant was constructed in line with ministry guidelines, I thought it was difficult to seek Mitsui's legal responsibility. And a court battle would take too much time. So the best way was to request Mitsui's financial cooperation for cleanup work around the plant," Tsuji said.

Yagi and other residents filed a lawsuit demanding 1.1 billion yen from Mitsui in December 1998. In the meditation accord reached last month, they agreed to withdraw the suit in return for 750 million yen.

Yagi admits that the settlement did not cover the question of legal responsibility, but he said he plans to pursue that matter in a separate lawsuit. He is among the supporters of six former workers at the incinerator who have filed a 530 million yen damages suit, claiming they became sick from dioxin exposure. One of the plaintiffs is receiving treatment for skin cancer.

Meditation was just the beginning of the final solution to the dioxin problem, Yagi said, adding that it is now his task to make sure that each clause of the accord is enforced.

Tsuji still contends that authorities did what they could to cooperate with the prefectural and central governments. "Indeed, we could not do everything promptly, but dioxin pollution on such a scale was a first experience for us -- just as it was for the residents," he said.

One of Tsuji's campaign promises when he was elected mayor in October 1996 was to build a relationship of trust with townspeople through discussions.

Tsuji will face voters again in October, when he will be judged on the basis of his earlier campaign promises and on a first term that was dominated by the dioxin problem.