Upper Austrian Environment Minister Rudi Anschober said it took Czech energy utility group CEZ eight days to react to the possibility of a leak after a defect was discovered on Temelin's steam generator. CEZ said that its information about the accident was prompt and adequate.
The measured radioactivity did not cross the permitted limit, but it was uncovered outside the zones of permitted incidence.
"We must insist on a total transparency. It must not be swept under the carpet by CEZ or the Czech Republic, it is an extremely risky technology," Anschober told the Austria Press Agency.
He said he wants the case to be dealt with by a group of independent experts.
Anschober said that on June 25th, a non-standard situation was uncovered at Temelin's unit two, which was out of operation at the time, and on the next day it was identified as a leakage between the primary and secondary circuits of the steam generator.
On July 3rd, Temelin announced that low radiation had been measured outside the "permitted" zones but said that neither the environment or the staff were endangered.
"The operator's reaction indicates that no one among the power plant staff considered a possible leak of radioactivity," Anschober said.
CEZ spokesman Marek Svitak said the nuclear safety authority, the Czech public as well as Austria were informed about the internal leakage on the steam generator and on the very low, below-limit values of radioactivity outside the permitted zones, but still within the power plant complex, immediately after it was uncovered.
With the exception of weekends and holidays, Austria has been informed about Temelin's current operation every day, Svitak said. He added that a series of independent tests have been carried out in the plant and beyond its border which prove that the outer environment has remained untouched.
Since the late 1970s, Austria has been fiercely anti-nuclear, starting with an unprecedented vote by its population that prevented the country's only plant from providing a watt of power.
But with the exception of Italy, Austria is surrounded by countries with nuclear power. It is opposed to Prague's plan to build another two units in each of the Czech nuclear power plants, Temelin and Dukovany, both of which are near the Austrian border.