ML20136E763

From kanterella
Jump to navigation Jump to search
Forwards Article by P Pocha & E Murphy Re Mounting Problems at Myaps.Advises That Plant Will Remain Shut Down at Least a Month Longer than Expected Because of Continuing Problems W/Electrical Sys
ML20136E763
Person / Time
Site: Maine Yankee
Issue date: 01/28/1997
From: Blanch P
AFFILIATION NOT ASSIGNED
To: Gietl D, Mulley G, Zwolinski J
NRC (Affiliation Not Assigned), NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV), NRC OFFICE OF THE INSPECTOR GENERAL (OIG)
Shared Package
ML20136C110 List:
References
NUDOCS 9703130320
Download: ML20136E763 (5)
v • d • e


Text

. _ _ . _ _ _ ... _.- .-_ .- _ _ _ _ . . _ . . . _ . _ _ _ . _ _ _ . _ . . _ . . . . . . . - _ . _ _ . _ ~

yA Front PAUL BLANCH <PMBLANCH91x.netcom.com>

2 Tot . WND2. WNP3 ( j az) , TWD1. TWP4 (gam) , ARD1. ARP1 (drg) , WND1. . . .

3 -Dates .

1/28/97 3:12am l Subjects MAINE YANKEE i

i Problems mount at Maine Yankee i

s l By Peter [Pochna and Edward D. Murphy i

=

i Staff Writers .

4 7 .

=A9 Copyright 1997 Guy Gannett_ Communications '

The Maine Yankee nuclear power plant will remain shut down for at

-= least a month. longer than expected because of' continuing

_ problems = with its electrical system, plant. officials announced

, Monday. .

~

They.also announced that a. problem with radiation leaking from =

4 cracked-fuel ~ rods is^ worse than expected.. Plant operators

] predicted = they would find about six leaky rods,-but instead i found 75 and repairs will cost about $6'million.

In addition, plant officials have told federal regulators that

three = motorized valves that are essential parts of the plant's 1 j-backup =. cooling system. don't work correctly.

[ Plantjengineers discovered Thursday:that under certain conditions j of =fextremely high heat,.the valves would not open. Since the plant has = been shut down for repairs >since~Dec. 5, the problem 3 does not posalan immediate hazard.-

l Maureen Brown, a plant spokeswoman,.said the valve problem did i -not = pose'authreat to the public when the plant was running, i because the = conditions needed to cause the malfunction were very unlikely to occur.

, But Kris' Christine.of Alna, who closely monitors the plant's =

operation, said the valve problem is alarming.

i

, I'm really concerned for the safety of my family, Christine j' said. =

Events at the' plant get more alarming every week

Even the Nuclear Regulatory Commission's senior resident l ' inspector at =

Maine Yankee admits he's worried about the plant's continuing =

problems.

1 9703130320 970306 PDR ORG NRRA %0 PDR

)

i l

l J

Jimi Yerokun said the NRC tends to treat each problem  !

independently, = but at Maine Yankee, it's become impossible to I ignore the pattern of = the last few years.

Frankly, I am very concerned about the rash of problems that l are = occurring here, Yerokun said. When you see one (problem) after = the other, it becomes a reason for concern.

This is not usual, to have four, five, six problems = you're dealing with. It's not a good feeling.

Ray Shadis, a member of Friends of the Coast, a group opposed to

= nuclear power plants, said Maine Yankee should be shut down for

= another review of the plant and its operations. He noted that i Maine Yankee has continued to find = problems beyond those i exposed by an independent review conducted last = year.

! What the prudent course of action would be is a thorough, =

top-to-bottom inspection of the plant, Shadis said, adding that 1 a = complete review might take at least a year with Maine Yankee  !

! off-line. j Cables are crossed i The 24-year-old plant in Wiscasset will not produce power before

mid-March, Brown said. The plant had planned to resume power

production in mid-February, but the inspection of miles of electric cables is taking longer than = expected.

l <

l A huge industrial facility has miles and miles of cable, i Brown = said. The work involved in tracking those cables carefully is = time-consuming.

Operators shut down the plant in December after workers found l that = cables controlling a steam valve vere crossed and routed )

improperly. = 1 The inspection of the wiring has expanded, with more than 120 )

temporary contractors helping Maine =

l Yankee workers search for places where cables may cross.

So far, workers have turned up six cases of cables strung too l close = together, Brown said, with most of them involving l equipment added to = the plant since it was built. l The cables are supposed to be separated so both primary and I backup = lines aren't knocked out in the event of a fire, Brown l said.

An extra month without the plant operating will cost the utilities = that own it about $15 million because they must pay l i

for replacement = energy.

l

We knew this would be a tough year for us, said Mark i Ishkanian, a = spokesman for Central Maine Power Co., which owns 38 percent of Maine =

Yankee. This just makes it a little tougher.

_ _ ___ _ .~ ___.- _ - _ ~._._ - .._ . _ _ . ._ _ _ . . _ _ _ _

l i

l

! 1 It is too early in the year to determine if the cost of Maine =

f Yankee's problems will be passed on to ratepayers.

1tods leak radiation The $6 million cost of the fuel-rod repair is primarily due to the ='need to replace eight entire fuel assemblies, each of which contains =

175 fuel rods.

Maine Yankee predicted Jan. 3 that it would only need to remove a l few = individual fuel rods. But an analysis over the past three

{

weeks has = found the fuel-rod cracking is much more extensive '

! than monitors indicated it would be. I l

Even so, Brown said there is no danger to the public.  !

l l There were no health or safety concerns, Brown said. The =- )

l radiation is within a closed-loop system. l i

The plant's power comes from the fuel rods, which are metal tubes I 13 = feet long and three-eighths of.an inch in diameter. They I contain = uranium pellets, which generate heat thr warms water j surrounding them. The rods are tied into = bundles that make up fuel assemblies, and the nuclear reactor = contains 217 assemblies.  !

Monitors detected that radiation was leaking from the rods last

June. =

The amount of leakage increased over the year, but by the time

the = plant shut down in December, the leakage remained far below l federal limits.

i Maine Yankee decided to repair the problem in January because the l = plant was already shut down for the electric-cable repairs.

l The plant is removing four ass'emblies because they contain leaky

l -

= rods, and four other assemblies because of concern that they might = soon develop leaks.-

Brown said plant operators are still searching for the cause of the = leaks.

i l She said monitors did not accurately predict the number of leaky L

rods = because the structure of the fuel assemblies was preventing radiation = from leaking through some of the cracks.

Safety f'eature may' fail

. The motorized valves that may not' operate correctly are part of l the = plant's backup cooling system. They are sliding pieces of

! metal that = run up and down on tracks, controlling the water

flow through pipes that run to the-fuel pool.

{

The problem Maine Yankee discovered is that high heat in the vicinity = of the valves would cause water pressing against the '

valves to = expand. That extra pressure would prevent the valves from opening. l l l Dave Lochbaum, a nuclear engineer with the Union of Concerned = l Scientists in Washington, D.C., said the valves are a critical safety = system.

The system is there for only one purpose: to prevent a meltdown, =

Lochbaum said. The fact that it wouldn't have worked is bad.

But Brown said that even if the valves did malfunction while the I

= plant was having a core cooling accident, plant operators would l be = able to find other ways to cool the fuel.

j. There are many actions that could be taken to provide the relief, = ]

l l Brown said. l I

She said the plant has already remedied the problem by keeping one.of = the valves permanently open. She said a relief valve j will be added = while.the plant is shut down for a scheduled refueling at the end of the year. [ NOTE FROM PMB: =

OPERATING WITH ONE VALVE OPEN MAY ALSO VIOLATE REGULATIONS le. I APX =

GDC 56]

Maine Yankee engineers examined the valves in reaction to a letter = the NRC issued in September. The letter directed all nuclear-plant = operators to examine their backup cooling  !

systems.

The letter said recent NRC inspections at various plants had found =

several safety-significant issues that could affect all plants.

Richard Rasmussen, the NRC's resident inspector at Maine Yankee, said = he plans to look into the problem this week. He said the plant will = not be allowed to start up unless its solution adequately addresses the problem.

Public image is issue Christine, the Alna resident, said it's a concern that the plant

= operated for many years with the faulty valves. She said she is also = concerned that an extensive NRC review of the plant last summer did not find the problem.

This is a very big thing for them to have overlooked,

Christine = said.

I l

L f 4 Brown tried to put a positive spin on the latest problems at the l = plant,. pointing out, for instance, that the inspection of the fuel n rods was conducted ahead of schedule.

Maine Yankee is at a crossroads. It is positioning itself to become = a' superior performer.in the industry, she said.

Getting there, we realize, has cost.us some public support. But

= once the citizens of Maine have all the facts in front of themselves = and once they give us time to make these repairs, they will once again have that high level of = confidence in-Maine Yankee.

Paul M. Blanch Energy Consultant 135 Hyde Rd.

L West Hartford CT 06117

! Tel: 860-236-0326 Fax: 860-232-9350 i

l' t

l l

t k

l l -

Retrieved from "https://kanterella.com/w/index.php?title=ML20136E763&oldid=2837728"