Richard Ness walks upon arrival for his trial at a district court in Manado, North Sulawesi, Indonesia (File Photo)

The U.S. Newmont Mining Corp and the chief of its Indonesian unit, American Richard Ness, are charged with dumping arsenic and mercury into a bay in 2003 that is located near its now defunct gold mine on the northern tip of Indonesia's Sulawesi island.

The pollution charges stem from the testing of the water in Buyat Bay by local police officials. They found high levels of contamination that officials say poisoned the water and marine life and made villagers near the bay sick.

Both Newmont and Ness deny the charges, pointing to duplicate testing that found no contaminants and independent tests by the World Health Organization that found the water to be safe.

Prosecutors are asking for a three-year jail sentence for Ness and heavy fines for Newmont if they are found guilty.

Ness, who was required to attend all 53 hearings during the course of the 20-month trial, says investors the world over are closely watching the case.

"There are a lot of people that are watching this one, there is a lot of interest all over the world on this, not only mining but all investment because I think fundamental for any investment is you need a rule of law, the contracts need to be upheld, and I think human rights have to be protected," said Ness. "That is a fundamental whether it is foreign investment, domestic investment, or any investment."

Indonesia, which has some of the world's largest deposits of gold, tin, metal, and copper, has been struggling to attract foreign investment due to widespread corruption, bureaucratic red tape, and an uneven legal system.

While some of the world's largest mining firms operate in the country, including U.S. giant Freeport-McMoran Copper and Gold, many of them have been accused of harming the country's rapidly deteriorating environment.

Torry Kuswardono, the mining campaign officer of the Indonesian environmental group WALHI, says if Newmont is found guilty, it will send a message to these big corporations that the rule of law must be followed in Indonesia.

"It means that we can control the power of the corporations, so you can control the harmful affect of the corporation and there is actually a certainty of law happening in Indonesia to protect and to save the people and the environment," he said.

Villagers for and against Newmont, along with environmentalists and mining advocates, are expected to attend Tuesday's hearing.