* Sees Q4 nickel production at 2,500 tonnes
* Postpones ore production to mid-2013 due to water problems
* CEO says needs to cut water levels significantly by spring
* Shares down some 5 pct (Adds CEO quote, detail, updates shares)
By Terhi Kinnunen and Jussi Rosendahl
HELSINKI, Nov 28 Finnish nickel miner Talvivaara postponed the restart of mining at its site in the east of the country by six months due to rain-related problems, raising fresh concerns over its future metals production.
Shares in the company fell around 5 percent in Helsinki and London by 1536 GMT and one analyst said the company may face two flat years of nickel output.
"It may be that production would not increase very much next year and there is a risk it won't pick up even in 2014," said the analyst, who declined to be named.
The Finnish company has been hit by a series of problems in the past year, including waste water leakage, production disruptions and the death of a worker.
Talvivaara halted mining and crushing operations at its Sotkamo mine in September for three to four months due to excess water and now says it will not restart operations until mid-2013, by which time the water should have been drained away.
Its chief executive said reducing the amount of water was a top priority as it was slowing metals extraction from stockpiles of ore estimated already to contain some 55,000 tonnes of nickel.
"We cannot return to normal before we have sorted out the water problems," CEO Pekka Pera told Reuters.
He added the firm was seeking a permit to release some 2.5 million cubic metres of cleaned waste water before snow melts next spring. Talvivaara's annual quota for waste water is 1.3 million cubic metres.
"I think we will reach normal operation ... during next summer," Pera said.
Earlier on Wednesday Talvivaara gave its production update for this year, forecasting around 13,000 tonnes of nickel after production was halted in November for more than two weeks by a leakage of toxic waste water.
The company previously said it targeted 50,000 tonnes per year running at full capacity. In 2011 nickel production was 16,000 tonnes.
Talvivaara has cut its annual production target twice this year. Guidance for 2013 is due early next year.
The company swung to an operating loss of 4.3 million euros ($5.5 million) in the third quarter due to production disruption and weak nickel prices and said it was considering new funding options, including convertible bonds and equity.
Analysts have said a share issue is the most likely option since the company's debt-to-equity ratio was already high at 141 percent.
"They are bleeding cash and debt maturities are approaching," said Fredrik Agardh, analyst at Handelsbanken.
Pera, previously chairman, returned to the role of CEO on Nov. 15 following public anger over the waste water leakage. (Editing by Dan Lalor and David Holmes)