MEXICO CITY - The temporary shutdown of a unit at Mexico's Laguna Verde nuclear power plant is the latest indication of the serious safety problems at the site, says environmental watchdog Greenpeace International.

The Federal Electricity Commission decided to close the unit after leaks were detected in the water system. The plant spokespeople played down the incident, but Greenpeace, with documents in hand, charges that the installation is unsafe and should be shut down entirely.

The Laguna Verde plant is located on the coast of the Gulf of Mexico, 469 km from the capital. It has been in operation since 1990 and generates 3.6 percent of the country's electricity.

LIMA - Peru's National Mining Society will make a presentation in May at the Fifth International Gold Symposium a new technology for neutralizing the contamination caused by the use of mercury in separating gold from its ore.

The new method consists of chemically stabilizing the heavy metal, turning mercury into sulfur to reduce its volatility and its leaching properties.

The product is then transformed into a sulfur polymer cement, allowing the altered mercury to be stored in inert, stable blocks.

BUENOS AIRES - Sixty environmental organizations in Argentina are urging President Eduardo Duhalde not to authorize a cooperation agreement with Australia that they say would turn Argentina into a radioactive waste-processing center.

The agreement was signed in 2000 by the Institute of Applied Research (INVAP), of the southern Argentine province of Río Negro, and by the Australian Nuclear Science and Technology Organization.

INVAP would provide a 180-million-dollar reactor, and has also offered a location - perhaps Ezeiza, in Buenos Aires province - for "processing and treating" the nuclear waste generated by the reactor.

QUITO - The conditions accepted by Huaorani leaders in Ecuador for the exploitation of petroleum in their territory "are an insult to the collective rights of this indigenous nationality," says the local environmental group Acción Ecológica.

The Huaorani granted the Italian company Agip Oil rights in the northeast province of Pastaza to build an oil well and a pipeline. In exchange, the company agreed to give them, among other things, 50 kg of rice, 50 kg of sugar, two blocks of fat, a sack of salt, two soccer balls, 15 plates, 15 cups and 200 dollars worth of medicine for each of the six communities.

Under the contract, the native group will also receive a training course for health workers, a radio, a battery, a solar panel and 3,500 dollars to build a classroom.