ZURICH, June 16 (Reuters) - The world's oldest operating nuclear power plant's restart has been delayed after the Swiss utility that runs the facility, Axpo, said on Friday that it must submit more information to the Federal Nuclear Safety Inspectorate (ENSI).
Beznau 1, which began producing electricity in 1969, has been offline since March 2015 because of maintenance issues.
Last November Axpo submitted documents to ENSI seeking clearance for the reactor to be restarted this spring, but on Friday it said that ENSI has asked for supplementary reports and material tests, pushing back the restart target date to Oct. 31 at the earliest.
The utility added that there is limited availability of external expertise over the summer to comply with ENSI's requests.
"Axpo remains convinced that no safety-technical reservations exist for the continued operation of the plant," the company said in a statement, adding that it expects that to be confirmed by the supervisory authority in due course.
Switzerland became a net importer of power in 2016, partly because of Beznau 1's prolonged closure and low precipitation that cut electricity production at the country's many dams. (Reporting by John Miller; Editing by David Goodman)