THE Government has played down reports that the Daya Bay nuclear power station has been plagued by technical problems since it was commissioned. Sources suggest the number of incidents may run into the hundreds. Although the Government and Hong Kong Nuclear Investment Company (HKNIC), which manages the plant, have both admitted there have been problems, neither would give the timing or the exact number. However, an HKNIC spokesman said the power station was ''running smoothly'' and that none of the technical problems was nuclear-related. Despite this, legislators last night called for comprehensive details of any problems occurring at the mainland plant, with accusations of a cover-up coming from legislator the Reverend Fung Chi-wood. ''A lot of information has been held up so we do not know the safety condition of the plant,'' he said. ''I would like to know what kind of incidents these are. The problem is that they have never been made public. ''Even if the incidents were small, they should let us know to put our minds at rest. What do they classify as an incident? All should be reported, written down and made available to the public.'' Although a spokesman for HKNIC last night could not verify the number of incidents, he stressed that none was related to safety. ''As far as we know the station is operating smoothly and there have been no safety related problems,'' he said. ''There have been minor incidents, but I cannot verify the number in the last two weeks.'' The revelations come just as China has agreed in principle to inform the Hong Kong Government of any problems at the power station. Details have yet to be worked out, but the offer represents a softening in China's position. It had previously insisted that incidents would not be reported unless there was a radiation leak beyond the site. Principal Assistant Secretary for Security (public safety, contingency planning for disasters) Andrew Kluth said his office would only be notified of ''off-site emergencies'' that might have a radiological effect on Hong Kong. He said China had been complying fully with its agreement and international standards on the reporting of safety matters. ''There are always problems at a power station, just like at any site,'' Mr Kluth said. ''You have maintenance, and correct problems as they occur. ''The safety control system at a power plant of this kind is so high, nearly anything can rate as an incident.'' He said incidents could be as simple as a vibrating pipe. Electricite de France, the French company that built Daya Bay, produces a safety report every year. ''They have about 50 of these plants and have had no serious problems - we'd know if they had; we would know of any incident that might have an effect on Hong Kong and nothing has,'' Mr Kluth said. ''There have been problems over the years and mistakes, but they are being corrected. That's part of the process with any construction project. ''None of these incidents are of concern to Hong Kong's safety. I can be absolutely blunt and say there is nothing to worry about. ''In France, these plants have hundreds of incidents, but they are of no significance. It may actually run into thousands, but these are problems that don't need reporting.'' Controversy has plagued the Daya Bay project since China voiced its intention to build the plant. Its construction provoked mass protests in Hong Kong after the 1986 Chernobyl disaster in Ukraine. One million people signed a petition opposing the proposal and in 1987 the multi-billion-dollar project suffered a major construction fault. There were further problems when only 316 out of 576 steel reinforcing rods were installed. In 1990, reports of corrosion prompted changes in the start-up procedure to clear sludge from the steam generator. China also did not acknowledge a fault line existed in the area until construction was under way. Seismologists in Guangzhou estimate an earthquake cycle of between 18 and 32 years. In June 1991, it was announced that the opening of Daya Bay would be postponed by one year because of problems with connecting pipes and fittings. At that time there had been 13,000 adjustments during construction. Legislative Councillor Mr Fung said it came as little surprise that so many incidents had occurred. ''A power plant is a very complicated machine,'' he said. ''When you say there's an incident it may be a little tube breaking. It's normal because there are so many small parts in a complicated plant. ''But we have to know how large the mechanical failure is - what kind of incidents they were.'' Other legislators have criticised the Government's contingency plan in case of an accident at Daya Bay, which calls for evacuation of those within 20 kilometres of the plant. ''Many people have yet to be convinced that the contingency plan drawn up by the Government would be adequate without the co-operation of the Chinese side,'' said legislator Leong Che-hung. ''Regrettably, the Government has dropped the idea of a territory-wide exercise to test our general response.'' Much of Hong Kong lies within 50 kilometres of the Daya Bay power station. About 70 per cent of the output from the plant, a joint venture between China and Hong Kong's China Light and Power Co, will be used by the territory.