Pilgrim Stuck at 22% After Storm Neptune: Beginning To a Pull Fitzpatrick
I keyed Mary into this?
Does Pilgrim need a new Condenser? Will it come down in power 21 times in 6 months? How old is Pilgrim's condenser?
Leaks force FitzPatrick nuclear plant to operate at reduced power
SCRIBA, N.Y. - The FitzPatrick nuclear power plant in Oswego County has been operating at reduced power since mid-June to compensate for persistent leaks in the plant's aging cooling system that have plagued the facility for the past two years.
Entergy Corp., owner of the 39-year-old nuclear plant, cut power output to about 85 percent of capacity in mid-June to try to reduce the frequency of leaks in its condenser.
The condenser, which circulates water from Lake Ontario to cool the reactor, sprouted leaks on average nearly once a week during the first six months of this year, each time forcing plant operators to reduce power until the leaks could be plugged.
Entergy officials have said they plan to replace all the condenser tubes during a refueling outage scheduled to begin next month. Crews will replace the existing brass condenser tubes with titanium tubes designed to be resistant to Lake Ontario sediments, which are abrasive and contribute to leaking, said Tammy Holden, speaking for Entergy.
Operating at reduced power cuts into what Entergy can earn from the nuclear plant, which company officials described last year as a "challenged facility'' because of its uncertain financial prospects.
The condenser is a large metal box positioned beneath the nuclear plant's generating turbine. Steam that drives the turbine then passes through the condenser, where it is cooled and returned to a liquid state by water from Lake Ontario, which circulates in thousands of small metal tubes.
The U.S. Nuclear Regulatory Commission has said the condenser leaks do not affect public safety, but the leaks have forced numerous unplanned power reductions.
During the first six months of 2014, Entergy was forced to reduce power 21 times to plug condenser leaks, according to NRC inspection reports. From April through June, the facility endured unplanned power reductions at a rate of 23 per 7,000 hours of operation, far exceeding the NRC's recommended limit of six.
NRC officials have criticized Entergy for not addressing the condenser leaks earlier. The condenser at FitzPatrick was last replaced in 1995, and the metal tubes within the condenser have an expected lifespan of 15 years, NRC officials said.
Entergy has not released the date when it plans to begin the September outage. Maintenance during the outage will employ more than 1,500 outside contractors in addition to the regular work force of 623, Holden said.
Love that Mary Lampert?
Pilgrim’s delay in restart - tube plugs falling out
My understanding is that the startup delay resulted from the following; please correct me if this is not accurate.
- Tube plugs fell out of the condensate tubes. Sea water then leaked into the fresh side of the condenser that contains the water that will go back into the reactor vessel.
- Because salt water would cause the stainless steel of the reactor to corrode and eventually cause a failure of the vessel and all its stainless steel pipes, the water is cleaned in the condenser demineralizer.
- During Pilgrim’s startup, because of the loss of tube plugs, the salt water intrusion was too much for the condensate demineralizers to remove and the feedwater system and the reactor vessel were in jeopardy of massive salt water intrusion.
- As a result, the condensate demineralizers were shut down and the resin in the demineralizer was replaced and the tube plugs were re-installed.
Questions:
1. Were some tubes in the condenser plugged because they had failed and were leaking?
a. When did the tubes start to leak?
b. Why were they plugged and not replaced?
c. Did NRC approve that fix?
d. What is the industry history of outcomes of plugging tubes versus replacement?
2. Why did the plugs come out- sounds like poor maintenance is that correct?
a. Is there a guidance or protocol calling for inspection of plugs prior to startup?
b. Were the tube plugs inspected before the recent plant started up?
c. What is the maintenance schedule and how does it match Entergy’s performance?
d. If there was an inspection, was it done right?
e. Supposedly there is a map of the tube sheet that shows what tubes are supposed to be plugged
i. Was the map accurate?
ii. Did the maintenance crew read the map correctly?
3. Did any salt get into the reactor?
a. What tests were performed to assure that salt did not get into the reactor?
b. If any salt did get into the reactor, what protocol should, and will be, followed?
Thank you in advance,
Mary Lampert
Pilgrim Watch
148 Washington Street -Duxbury, MA 02332
Tel. 781-934-0389/Email: mary.lampert@comcast.net
From: McKinley, Raymond
Sent: Tuesday, February 24, 2015 12:58 PM
To: mary.lampert@comcast.netThe Annual Assessment Meeting will most likely occur on March 18. A public meeting notice will be forthcoming soon. We also plan to discuss the results of the 95002 Supplemental Inspection during that meeting. The Special Inspection that was launched following winter storm Juno is still in progress. That report will be issued within 45 days from the exit meeting, so we will not be in a position to discuss the findings of that inspection at the March meeting.
We can answer some questions relative to the facts surrounding winter storms Juno and Neptune, but we will not be able to discuss any pre-decisional findings.
To your attached questions:
Were some tubes in the condenser plugged because they had failed and were leaking?
Yes, some tubes were previously plugged due to previously identified leaks.
a. When did the tubes start to leak?
The previously plugged tubes began to leak again following the planned shutdown for winter
storm Neptune.
b. Why were they plugged and not replaced?
Tube plugging is the most common repair used in the industry. Condensers are constructed with more tubes than needed to allow any leaking tubes to be plugged. Eventually, condenser efficiency is impacted which results in lost generation revenue for the licensee.
At or near that point, licensees will either re-sleeve the tubes or replace the condenser water
boxes.
c. Did NRC approve that fix?
This is non-safety related equipment repair, and NRC approval is not required. However, as stated above, this is a normal repair used in industry.
d. What is the industry history of outcomes of plugging tubes versus replacement?
Plugging is very effective. However, plugs can and do fall out or become loose. The decision to repair or replace is a licensee decision.
2. Why did the plugs come out- sounds like poor maintenance is that correct?
Thermal and hydraulic cycling associated with shutdowns and startups were most likely the cause. There is no reason to suspect poor maintenance.
a. Is there a guidance or protocol calling for inspection of plugs prior to startup?
Licensees will typically inspect water boxes during a refueling outage but not for mid-cycle outages unless they perform water box work. They did not perform water box work during the Juno or Neptune outages, so there was no reason to perform a water box inspection.
b. Were the tube plugs inspected before the recent plant started up?
No, see previous answer.
c. What is the maintenance schedule and how does it match Entergy’s performance?
NRC does not regulate condenser maintenance activities. Licensee’s typically perform condenser maintenance during refueling outages or during online maintenance windows. It is in their own best interests to perform condenser maintenance to avoid unplanned down powers / outages from an economic perspective as well as to protect their capital investment. In addition, NRC does have a Performance Indicator which tracks unplanned down powers, so such issues can draw regulatory scrutiny. Pilgrim’s unplanned down power Performance Indicator is solidly in the GREEN range, so it has not been a problem to this point.
d. If there was an inspection, was it done right?
NRC does not inspect licensee condenser water box inspections.
e. Supposedly there is a map of the tube sheet that shows what tubes are supposed to be plugged
i. Was the map accurate?
ii. Did the maintenance crew read the map correctly?
As stated above, NRC does not inspect this activity. However, when leaks were identified
following the winter storm Neptune startup, the licensee used their tube sheet maps to make
sure plugs were still there and tight. They replaced missing plugs and tightened or replaced
any loose plugs.
3. Did any salt get into the reactor?
The licensee monitors the condenser hotwell and condensate demineralizer discharge for conductivity and chlorides. They detected rising chlorides and conductivity in both locations during the startup which drove them to take corrective action
a. What tests were performed to assure that salt did not get into the reactor?
See previous answer.
b. If any salt did get into the reactor, what protocol should, and will be, followed?
The licensee follows Electric Power Research Institute (EPRI) guidance, and their procedures drive them to take timely and appropriate action based on the severity of the chemistry conditions. In this case, the action was to hold at reduced power until the issue was corrected. Severe chloride or conductivity excursions can require an immediate shutdown, but the chemistry levels were manageable in this case. The problem was identified and corrected and chemistry levels returned to normal. The licensee will continue to monitor reactor water chemistry and take appropriate action in accordance with the EPRI guidance and plant procedures. Our inspectors will follow up to ensure that the licensee follows their reactor water chemistry procedures.
Sincerely,
Ray McKinley
Chief, Division of Reactor Projects Branch 5
U.S. NRC Region I
Subject: RE: Comments and questions regarding Pilgrim's delay in restart - tube plugs falling out.
Attachments: 02.23.15 QUESTIONS NRC TUBE PLUGS DELAYING RESTART.pdf
Mary,
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