(Repeats to widen distribution; no changes to headline or text)
* Top refinery could be down for a month - Mining Min
* Authorities to inspect "every pipe" at refinery
* Aconcagua refinery should restart next week
* No risk seen to mines, energy supply normal (Recasts, updates with comment from Bio Bio official, mining details)
By Terry Wade
BIO BIO REFINERY, Chile, March 3 (Reuters) - Chile's top oil refinery, damaged by a devastating earthquake, could be shut down for a month, which would boost the need for fuel imports to the world's top copper producer.
The Bio Bio refinery in south-central Chile has remained down since Saturday's 8.8-magnitude earthquake ravaged the region, killing more than 800 people, briefly shutting down copper mines and mangling roads.
Chilean Mining Minister Santiago Gonzalez, who was about to travel to Bio Bio, told Reuters the 116,000 barrels of oil per day refinery could be down "for a maximum of a month."
On the outside, the site shows no signs of damage from the quake, one of the biggest in more than a century. Shift manager Pedro Villareal said it will take "some time" for operations to resume, but declined to give an estimated date.
He said the Bio Bio refinery was untouched by giant waves that nearly wiped out nearby coastal hamlets.
Energy-starved Chile also closed its Aconcagua refinery, slashing around 220,000 barrels of oil per day in total refining capacity.
Aconcagua is expected to restart next week, state oil company ENAP said.
"We know there are problems and we are going down there now," Gonzalez said inside a military plane about to depart to the quake-hit city of Concepcion, near the refinery.
Chilean President Michelle Bachelet said earlier that she sees no risk of fuel shortages. Energy officials have said the South American country would buy as much fuel as needed to secure supply. [ID:nN02209214]
ENAP on Tuesday declared force majeure on a crude shipment from Ecuador's Petroecuador.
Refinery problems are forcing Chile to import more oil products from Asia and the United States to make up for supply, boosting markets in those regions. [ID:nSGE6220GX]
Gonzalez said he saw no risk to Chile's all-important copper sector after all the important mines returned to normal earlier this week, and energy supply was flowing to the industry.
Chile's Codelco, the world's top miner, said it was exporting normally after the quake, and had no power supply problems, which had fueled worries over output levels in the mining powerhouse that lifted world copper prices.
Copper prices are up around 5 percent since markets reopened Monday after the quake. But a falling dollar eclipsed worries about supply interruptions from Chile.
The quake knocked down power to key mines from Codelco [CODEL.UL] and Anglo American, briefly halting about one fifth of the country's output on Saturday.
Anglo America (AAL.L) had also recovered from the quake. Affected mines -- Los Bronces, El Soldado and Mantoverde -- sustained only minor damage and restarted on Sunday. The deposits account to about half of Anglo's annual output of 669,800 tonnes.
The company added that its Chagres smelter was due to ramp up to full production on Wednesday.
But a steel operation in Concepcion had to halt operations.
"At Scaw Metals' plant near Concepcion, considerable damage has been caused preventing the resumption of operations until further notice," it said.
Additional reporting by Mica Rosenberg and Alonso Soto in Santiago; Editing by David Gregorio