Duxbury Nuclear Advisory Committee letter to NRC re failed annunciators

TOWN OF DUXBURY NUCLEAR ADVISORY COMMITTEE
July 17, 2013

William Dean
Region I Administrator
U.S. NRC
Via Email

Hello Bill:

The committee and community are concerned regarding Event 49189 – Unusual Event Declared Due to Loss of Control Room Annunciators, July 15, 2013. The report reads:

The licensee declared a Notice of Unusual Event resulting from a loss of control room annunciators for greater than 15 minutes. The EAL Condition is SU 4.1. Compensatory measures have been established per Abnormal Operating Procedures. The plant continues to operate at 100 percent power.

The licensee has called for support staff to troubleshoot the issue. No other major components are out of service.

Pilgrim remained and remains at 100% power. The following up-date was issued by the NRC:

“Annunciator indication has returned for some time and appears to be working. Engineering and electrical instrumentation and control staff are onsite to troubleshoot but have not established any cause. The licensee remains in the Unusual Event until additional confidence can be established in annunciator indication.” (Emphasis added)

What concerns us is that the reactor remained, and continues to remain, at full power despite the fact that the causes (s) have not been established.

To us it would seem reasonable to shut down until a root cause analysis has been performed and whatever requires a fix is fixed. Until that is done, we fail to see how the NRC can provide reasonable assurance for public health and safety.

The annunciator is like the warning light on our car’s dashboard to let the control room staff something is wrong; it is important for defense in depth. If whatever caused the annunciator malfunctioning happens again and coincides with a real problem, Pilgrim essentially will be “flying blind.

Neil Sheehan, NRC Public Affairs, said that,

The alarms were back in operation within a few hours, but the company is continuing to troubleshoot the problem. It should be noted that operators are still able to monitor plant parameters using control room panels even if the annunciators are unavailable.

This is not reassuring absent information on

a. Exactly what information allows “operators (to) still (be) able to monitor plant parameters using control room panels even if the annunciators are unavailable”?

b. What information provided by annunciators that is not provided by “other parameters?

c. What is the significance of what is supposedly provided by other means? How does information provided by “other means” compare in significance to the information provided by the annunciators?

What is the basis, if any, for either Entergy or the NRC to assume that the annunciators will not fail again, given that they have already failed once and that no one seems to know the cause?

We understand that the annunciators have failed at other reactors; and a September 2012 Alarm System Research Plan (DOE/ID-10-19888, Idaho national labs) said that current analogue controls are obsolete and that replacement parts are difficult to get. They recommend moving to digital control interfaces. Is Pilgrim in analogue or digital; if required is Pilgrim able to get replacement parts if still in analogue?

We take this Event very seriously, especially in the context that as of today Pilgrim has had 14 Event Reports since January 1, 2013. This indicates to us that both equipment and management are at a low point. Entergy is not likely to spend monies for fixes unless required by NRC to do so because Entergy’s reported earnings this quarter again were down. Operating an old reactor on the cheap is bad news for the community.

We look forward to a substantive response; and enjoy your boat the remainder of the summer.

Sincerely on behalf of the committee,

Mary Lampert
148 Washington Street
Duxbury, MA 02332
Tel 781-934-0389

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