Pembroke Mayor Ed Jacyno is asking why Atomic Energy of Canada Limited did not inform area municipalities about a radioactive spill at Chalk River last December.

In the wake of the revelation earlier this week that radioactive tritium and contaminated heavy water leaked from the National Research Universal (NRU) reactor, questions are being raised by municipalities downstream from the nuclear facility.

Mayor Jacyno said Wednesday he believes federal regulators require AECL to tell the public that an incident has taken place.

"As we are living downstream, we do expect to get notification," said Mayor Jacyno. "We need to know what's going on when there is an occurrence. Why did it occur six weeks after the fact?"

During the incident on Dec. 5, amounts of tritium were released into the air at the NRU reactor.

AECL officials managed to contain another 800 litres of contaminated water now being stored in special drums.

The NRU, which produces 70 per cent of the world's medical isotopes, was shutdown briefly.

The leak was revealed in an internal report to the Canadian Nuclear Safety Commission (CNSC) that was obtained by Sun Media.

The nuclear regulator also said another part of the reactor has been leaking water from a 2.4 inch crack in a weld. Technicians have been pumping water into the unit to replace the estimated 7,000 litres a day that has been spewing from the seam. The CNSC said the water has "a very low level of radioactivity." The water is being dumped into the Ottawa River.

Sitting 16 kilometres south of the Chalk River Laboratories, Petawawa is the first downstream municipality in the vicinity. Mayor Bob Sweet said he is concerned that the town was not informed of the spill.

"We should have been made aware of it," said Mayor Sweet. "I don't think there was any intent to cover anything up, but I think they had an obligation to tell us."

The internal report stated there was no threat to the health of workers and the tritium, a radioactive isotope of hydrogen, released into the air posed no significant danger to the environment.

Mayor Jacyno takes AECL at its word that the situation was contained. He noted that the company has maintained good relations with the area and pointed to a protocol in which Chalk River officials meet quarterly with municipal leaders from Pembroke, Petawawa and Pontiac County to keep them apprised of developments at the facility. The mayor has since fired off a letter to Shaun Cotnam, AECL manager of site and community affairs, seeking an explanation.

"They have been a good neighbour, but we're dealing with a product that could have an impact on those living downstream," he said. "It may have been an oversight, but it's unacceptable."

Mayor Sweet anticipates Petawawa will keep up good working relations with AECL adding he still has faith in the researcher and their efforts at the facility. AECL has since sent a press release to the mayor which he will review with town councillors next Monday.

"AECL is one of the most regulated industries. Maybe there will be a need to look at procedures," said Mayor Sweet. "It was one of those things that was unfortunate and hopefully it won't occur again."