Multiple civic groups in Japan have continued to oppose the country's plan of dumping nuclear-contaminated wastewater from the crippled Fukushima Daiichi nuclear power plant into the Pacific Ocean, exhorting the government to take the long-term impact into account to avoid entailing endless trouble to future generations.

"The problems regarding nuclear-contaminated water and the health hazards of radiation may further show their impact after a century, the situation 500 years or even 1,000 years later must be taken into consideration before judging whether the wastewater can be discharged into the sea," said Yoshitaka Ikarashi, the Japanese representative of the Somei Platform, or the Japan-China common market promotion association.

Also a resident of Iwaki city in southeastern Fukushima prefecture, he made the remarks during his recent speech at Meiji Gakuin University. He has been involved in volunteer activities for disaster relief and reconstruction in the prefecture after the devastating earthquake in 2011.

When referring to the water-dumping plan, Ikarashi mentioned a Japanese saying that "one cannot do things well if he only considers the immediate," citing carpenters building temples in ancient Japan as an example.

In order not to be blamed by future generations, the carpenters would think ahead and will strive to leave a building that can stand the test, according to him, stressing that the century-long impact from now must be taken into consideration regarding the nuclear-contaminated water.

"The sea is the common property of the world and Japan cannot make decisions alone," said Ikarashi, adding it is premature to make judgments as the possible future hazards of nuclear-contaminated water containing radioactive materials have not been verified.

He added that the current treatment methods of the relevant parties are also not doing their best to protect the marine environment and human health, the viewpoint of which was echoed by other local experts.

Hideyuki Ban, co-director of the Tokyo-based Citizens' Nuclear Information Center, told Xinhua in an interview that in order to prevent pollution of the marine environment, countries should use the most practicable methods at their disposal in accordance with their capabilities.

The nuclear expert believes there are other ways of treating contaminated water, such as cement solidification, that are more practical than dumping it into the sea.

According to Ban, the power plant in Fukushima has stored more than 1.3 million tons of nuclear-contaminated water, which will continue to increase in the future, and according to the plant's operator Tokyo Electric Power Company (TEPCO), the discharge is planned to continue for more than 30 years. If fish and shellfish are contaminated, it will ultimately affect the health of humans at the top of the food chain.

The expert pointed out that TEPCO only assessed the uniform spread of radioactive material in the sea. "In fact, the ocean terrain is undulating, and the complex ocean currents do not flow in only one direction. It is not surprising that high concentrations of radioactive substances appear in the process," he said.

Masanobu Sakamoto, president of the national federation of fisheries cooperatives known as JF Zengyoren on Thursday met with Japanese Minister of Economy, Trade and Industry Yasutoshi Nishimura, and handed over to the latter a petition stating the federation's unchanged opposition to the discharge plan.

The president called the planned discharge of nuclear-contaminated water "a matter of life and death" for the fishing industry, and opposed the authorities' decision to start the discharge without the full consent of the fishing industry.

Ikarashi also questioned the end date of the water discharge, noting that Japan does not have the final treatment technology for decommissioned nuclear reactors, while the schedule for completing the disposal of waste reactors is completely unclear. "Under such circumstances, how can this decision-making generation bear the responsibility for the discharge after they are gone?"

"I probably won't live another 30 years, but as long as I live, I will continue to call on the government to change its policy," said Ban, who is now in his 70s.