Manila. The Philippines, one of the world's top suppliers of nickel ore, will this week start limiting the land that miners can develop at any one time as new rules to protect the environment take effect.

The new curbs, backed by President Rodrigo Duterte, target 29 of 48 mines operating in the Philippines, which are nickel producers supplying ores to the world's leading market, China. Reuters first reported the new set of restrictions in April.

Mining is a deeply contentious issue in the resource-rich Southeast Asian country after past examples of environmental mismanagement.

The industry group Chamber of Mines of the Philippines said it supports the government order.

Under the new rules, a 20-meter "buffer zone" will be established inward from the mining tenement boundary and near rivers and streams, where metals extraction will be banned.

Nickel miners will be limited to a production area ranging from 50 to 100 hectares at any one time, depending on the size of production and whether they have a processing plant.

The government order, which takes effect this week, will allow mines producing up to 1 million tons of nickel ore a year to work on 50 hectares at any one time.

Those producing more can work on 60 hectares up to 100 hectares, while projects with a processing plant will be allowed up to 162 hectares.

"If mining companies intend to open a new area, say 100 hectares, they should also progressively rehabilitate the same 100 hectares that they previously disturbed," Manila's Geosciences Bureau director Wilfredo Moncano told Reuters on Thursday (06/09).

Duterte told miners in April to reforest areas where they operate, warning he would revoke their permits if he doesn't see trees as tall as he is in six months.

Miners will be required to put up a 5 million Philippine pesos ($93,370) performance bond every year as a guarantee that they will comply with the requirement on mine rehabilitation. The bond will be forfeited if they fail to comply.

"Our member-companies are fast-tracking efforts to comply with the order, including the revegetation of mined-out and inactive mine areas," Rocky Dimaculangan, the Chamber of Mines' vice president for communications, told Reuters.

Nickel ore output fell 10 percent in the first half of 2018 from a year earlier to 9.43 million dry metric tons, government data showed.

Eleven of the nickel mines had zero output during the period because their operations were suspended or they were under maintenance status.

Reuters