Dec. 12 (Bloomberg) — The U.K. nuclear regulator, studying a reactor design proposed by Areva SA and Electricite de France SA, said the last of its technical concerns had been resolved, bringing EDF closer to expansion in southern England.

The Office for Nuclear Regulation last December gave “interim” approval to Areva and EDF’s design for a European pressurized-water reactor. It asked the companies to address a list of 31 concerns, the last of which was settled on Dec. 7, the watchdog said today in a website statement.

EDF is among companies studying British nuclear expansion as the government seeks to replace an aging fleet of electricity plants without adding to carbon emissions. The French utility operates eight U.K. atomic power stations with a combined generation capacity of almost 9 gigawatts, and has proposed to add new reactors at its Hinkley Point and Sizewell sites.

“The regulators will confirm soon whether due process is now complete to decide whether to issue a design-acceptance confirmation,” the ONR said today. EDF and Areva still need consents related to planning and siting their proposed model. EDF is due to decide on investment at its Hinkley Point complex by year-end.

To contact the reporter responsible for this story: Sally Bakewell in London at Sbakewell1@bloomberg.net

To contact the editor responsible for this story: Reed Landberg at landberg@bloomberg.net