Pilgrim had another unplanned shutdown  yesterday morning, Septemeber 6th — the second shutdown in nearly three weeks due to a valve malfunction.

The first shutdown was on August 18 and lasted several days. It was caused by a failed valve that is designed to prevent radioactive contamination from leaking into the envionment during an accident.

Yesterady, at approximatley 8:30am, Pilgrim was manually shut down again when water levels in the reactor pressure vessel fluctuated due to a mechanical malfunction in another valve. The valve is designed to pump water into the reactor vessel, which is boiled and created into steam. The steam is what is used to turn a turbine and create electricity. The water also serves other important purposes — for instance, it makes up water that keeps the nuclear fuel cool.

The shutdown occured at the same time Pilgrim was operating at reduced power due to the cooling water coming in from Cape Cod Bay being too warm. Pilgrim licence requires the incoming water to not exceed 75 degrees F. This has become a problem for Pilgrim over the last few years due to rising air and water temperatures.

On top of this most recent valve proble, Pilgrim also had a electrical arcing in a power line going to the plant on Monday night – another problem that has occured in the past.

Pilgrim has had a long histoy of mechanical problems and unplanned shutdowns. The NRC created a webpage early this year dedicated to Pilgrim. It was started due to Pilgrim’s poor performance and the high level of public interest in what’s happening at the aging plant.

The U.S. Nuclear Regulatory Commission is currently investigating the valve problems.

Related media articles:

Another shutdown for Pilgrim, Cape Cod Times, Sept. 6, 2016

Pilgrim Nuclear Power Plant Shuts Down Following Valve Problem, CapeCod.com, Sept. 6, 2016

Pilgrim Nuclear Power Station shut down because of malfunctioning valve, Cape Cod Times, Sept. 6, 2016