* Vale nickel plant at Goro closed early May after acid leak
* Spill sparked violent protests causing more than $20 mln
* Goro nickel plant has troubled history with spills,
* World nickel prices up strongly this year on supply
(Adds quotes, detail on statement)
By Cecile Lefort
SYDNEY, June 2 New Caledonia authorities said on
Monday they have authorised a conditional restart of
Brazil-based Vale's nickel operations, which were
suspended more than three weeks ago after acid-tainted effluent
spilled into a river.
The leak sparked violent riots by young Melanesians that
caused more than $20 million in damage to buildings, equipment
and vehicles and left three policemen with gunshot wounds.
Police remained on alert as protesters maintained a presence
near the plant.
"The situation is calm and some (protesters) are still
camping near the plant," said a local government spokeswoman.
Some protesters, who have been frustrated by the lack of
response from indigenous Kanak chiefs to the chemical spill, are
seeking the permanent closure of the mine - something Vale said
last week was not on the table.
Vale could not immediately be reached for comment on when
production would restart.
The Southern Province of the French-administered Pacific
island noted it was Vale's sixth major incident at the $6
billion Goro site and set hightened safety standards as a
condition of the mine operations resuming.
Conditions also included a full audit of safety management
and the establishment of a multi-party surveillance committee.
Vale, the world's second-largest nickel miner, employs high
pressure technology and acids to leach nickel from abundant
tropical laterite ores.
"Every time (there is a problem with Vale), it's the same
response by the Province... Yet, it happens again," said Louis
Kotra Uregei, president of New Caledonia's Labour Party.
Uregei is asking for a halt of the acid-based nickel
"We need to focus on ore mining and let the processing get
done somewhere else," he said.
Nickel mining is a key industry in New Caledonia, which
holds as much as a quarter of the world's known reserves. Vale's
plant is the second-largest employer in the southern province,
with some 3,500 employees and contractors.
LME nickel prices finished May up 5 pct at $19,250,
having soared 40 percent so far this year, largely on supply
concerns from major producer Indonesia.
(Additional reporting by Melanie Burton; Editing by Lincoln
Feast and Richard Pullin)