CHALK RIVER, Ont. - Atomic Energy of Canada Ltd. says it estimates that the National Research Universal reactor will resume medical isotope production by the end of July.

The NRU reactor in Chalk River, Ont., has been off-line for more than a year for repair of a radioactive water leak.

Doctors who rely on medical isotopes to diagnose ailments have said they are frustrated it is taking so long to repair the leaky reactor.

AECL says detailed inspections of the repair by the Technical Standards and Safety Authority have declared the reactor fit for service.

Some inspections were repeated following an earthquake last week but AECL says no changes were detected.

AECL will appear next Monday at a Canadian Nuclear Safety Commission hearing considering an application to restart the reactor.

AECL says the reactor is in a safe shutdown state and return-to-service activities are in progress.