* Lawmakers to vote Wednesday whether to confirm or reject Lopez
* Lopez assailed on legality of steep fee to remove stockpiles
* Philippines is world's top nickel ore supplier (Adds quotes, background)
MANILA, May 2 (Reuters) - There is a 50 percent chance that Philippines Environment Secretary Regina Lopez may lose her confirmation vote after holding the position for nearly a year, said the head of the country's Senate environment committee on Tuesday.
"It's still a 50-50 chance for Gina," Senator Manny Pacquiao, chairman of the committee, told reporters after Lopez gave testimony at a committee hearing, referring to the minister by her nickname.
Congressional confirmations in the Philippines typically happen months after ministers start work. President Rodrigo Duterte appointed Lopez on June 30, 2016. Lawmakers will vote on her fate on Wednesday.
Lopez, a committed environmentalist, angered the mining industry after ordering the closure of 22 of the Philippines' 41 mines in February to protect water resources in the world's top nickel ore exporter. later cancelled dozens of contracts for undeveloped mines and just last week banned future open-pit mining projects as she tightened her crackdown of a sector she blames for extensive environmental damage. Tuesday's hearing, Lopez struggled to defend the legal basis for requiring nickel miners that remove their ore stockpiles to set aside an additional 2 million pesos ($39,948) per hectare of disturbed land on top of funds already set aside to repair environmental damage, only saying that she wanted to help farmers in those areas.
"I'm a very out of the box person," she said.
Reuters reported in March that eight nickel miners suspended last year for environmental infractions were allowed to remove previously mined ore that could pose environmental hazards. But, the order added the additional funds be set aside to fix any further environmental pollution. can't invent fees without congressional authority," Senator Alan Peter Cayetano later told reporters.
Cayetano, an ally of Duterte, expects heated deliberations on Wednesday when members of the powerful Commission on Appointments votes on Lopez's fate. Duterte has largely backed Lopez's crackdown.
The same panel in March rejected Perfecto Yasay as foreign minister, their first dismissal of a member of Duterte's cabinet.
Mining is a contentious issue in the largely underexplored Southeast Asian country after past examples of environmental mismanagement, including a 1996 tailings leak at Canadian-owned Marcopper Mining Corp's copper mine in Marinduque that contaminated rivers.
($1 = 50.0650 Philippine pesos)