A steam leak brought on by an involuntary chemical reaction Wednesday at France\'s oldest nuclear plant led to two people being slightly burnt, officials said. The accident occurred at the Fessenheim nuclear power plant in northeastern France within 1.5 kilometres (one mile) of the border with Germany and about 40 kilometres (25 miles) from Switzerland. \"It was not a fire,\" the local prefecture said. \"There was an outlet of oxygenated steam\" produced after hydrogen peroxide reacted with water in a reservoir. About 50 firefighters have been deployed, an official from the service said. French power supplier EDF said \"two people were slightly burnt through their gloves.\" On stream since 1977, Fessenheim has two water reactors. It is built along a huge canal and draws water for cooling from the Rhine river. Due to its location, it is vulnerable to seismic activity and flooding and is provisionally scheduled to close in 2017.