ML20059M021
| ML20059M021 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 09/18/1990 |
| From: | Matthews D Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20059M016 | List: |
| References | |
| 90-617-03-OLA, 90-617-3-OLA, OLA, NUDOCS 9010020414 | |
| Download: ML20059M021 (6) | |
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u September 18, 1990 UNITED STATES OF AMERICA NUCLEAR REGUI.ATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSINO BOARD in the Matter of
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GEORGIA POWER COMPANY
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Docket Nos. 50424
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50-425 (Vogtle Electric Generating Plant,
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Units 1 and 2)
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ASLBP No. 90 617 03-OLA
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Facility Operating License No. NPF 68
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Amendment No. 31, July 10,1990
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and
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Facility Operating License No. NPF 81
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Amendment No.11, July 10,1990
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AFFIDAVIT OF DAVID B. MATTHEWS IN SUPPORT OF NRC STAFF RESPONSE IN OPPOSITION TO GEORGIANS AGAINST NUCIFAR ENERGY'S AMENDED PETITION FOR 1FAVE TO INTERVENE I, David B. Matthews, having first been duly sworn, hereby deposes and states as follows.
I am employed as Director, Project Directorate 113, Office of Nuclear Reactor Regulation, U.S. NRC, Washington, D.C.
I attended the University of Virginia, Charlottesville, VA, and received a B.S.
degree in Electrical Engineering in 1970. I then attended Cornell University, Ithaca, NY, and received an M.S. degree with a major in Electrical Engineering in 1972.
In my present position I direct and supervise personnel responsible for the regul. nary oversight and licensing reviews for eleven nuclear units operated by Duke Power Co. and Georgia Power Company. These responsibilities include review and M E k N !a4 g
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approval of safety evaluations of licensee submittals invohing plant modification and l
related changes to the technical specifications issued with each operating license.
Prior to assuming my present assignment in 1988, I supervised personnel responsible for review of applicant and licensee plans prepared in response to those j
portions of 10 C.F.R. Part 50 related to emergency preparedness at nuclear facilities. I j
was also responsible for managing and directing the onsite review of emergency preparedness programs to assure compliance with Commission requirements - both as they applied to operating reactors and as they are required to be implemented prior to l
issuance of an operating license.
Prior to 1981, I served as Chief, Reactor Security Section, Division of Safeguards, U.S. NRC. In this capacity I was responsible for superising the review of reactor security programs developed in response to the requirements contained in 10 C.F.R. Part 73.55.
These requirements include provisions for physical security hardware and programs, contingency plans, and guard training and qualification programs. My previous assignments within the NRC, prior to May of 1980, included duties of increasirg i
responsibility in the area of nuclear power plant and fuel facility security, safeguards and contingency planning. These duties began with my initial assignment as an NRC plant protection analyst in August 1975.
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Between 1972 and 1975 I was employed as an electrical engineer with Westinghouse Electric Corporation in Hunt Valley, MD.
My final position with Westinghouse was with the Nuclear Instrumentation and Control Department.
I have been requested to review the Georgians Against Nuclear Energy (GANE) petition to intervene dated July 23, 1990 and its undated Amendment To Petition For Leave To Intervene. I and other members of the NRR staff have particularly reviewed
. f the proffered contentions as they may relate to the amendments to revise technical specification 4.8.1.1.2h(6)(c) requested by the licensee on May 25,1990 and granted by the NRC on July 10,1990. 55 Fed. Reg. 32337 (Aug. 8,1990). That request was for permission to bypass the high jacket water temperature (HJ%T) trip switches on the
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l diesel generators.
l The following is the Staff's technical analysis of GANE's specific concern with Georgia Power Company's " request to bypass the high Jacket water temperature switch on the backup generator that caused the March 20,1990 accident at Plant Vogtle" and the contentions proffered by GANE.
The following should be recognized:
1.
For each Vogtle Unit there are two emergency diesel generators (EDG)
(four on the site) that provide power to the plant in the event that normal offsite power (the preferred source of power) is lost to the plant site.
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Each Vogtle EDG is aligned to its own electrica! power train (i.e. an independent and separate set of electrical equipment capable of supplying power to the equipment necessary to safely shut down the Unit).
3.
This design of two EDGs aligned to separate and independent trains ensures that in the event a failure occurs in either an EDG or its associated train, the other EDG and its associated train remain available to supply emergency power to the facility. In addition to the two EDGs, each Vogtle i
Unit can be supplied power from offsite through either of two redundant
" reserve auxiliary transformers." As a result, there are four different means of supplying power to the plant equipment necessary to safely shut down the Unit.
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4.
The EDGs have an elaborate array of " protective trips" which are designed I
to protect the EDG and its constituent components from damage. One of these protective trips is the high jacket water temperature trip. 'Ihis EDG
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trip consists of three temperature sensors that sense EDG jacket water temperature and " trip"if the water temperature rises to 2007 247. If two f
out of three of these sensors trip, the EDG is shut down. On March 20, 1990, the root cause for the Unit 1 "A* EDG trip is believed (not conclusive) to be intermittent actuation (failure) of two out of the three sensors. The actual water temperature is not believed to have been 2007.
It should also be noted that these switches do not control the flow of Jacket l
water to the EDG as GANE alleged in its earlier Petition.
f GANE's concern also states that "if this switch is bypassed the potential.for l
L generator engine to overheat is increased." *If the generator engine were damaged no power would be available for the plant site." With regard to this portion of GANE's l
concern it should be recognized that:
The GPC request to manually bypass (i.e., installing valves which are closed 1.
and prevent the sensors from tripping the EDG) the high jacket water temperature sensors is likely to increase the potential that the EDG could be damaged due to overheating. This is because if there is a failure within the EDG jacket water ecoling system, the EDG would no longer be automatically tripped and shut down. Instead, operator action would be relied uponin response to the EDG high jacket water temperature alarm located both locally (EDG room) and in the main control room.
As i
L mentioned above, the Vogtle design incorporates two redundant and L
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' -5' separate EDGs which provide power to two separate electrical power trains.
If an EDG problem occurred in which operator action failed to prevent EDO damage, the redundant EDG and its associated toer train are.
designed and capable of providing sufficient power to plant equipment to safely shut down the plant.
2.
Contrary to what GANE seems to allege, by manually bypassing the high jacket water temperature EDG trip and thus preventing spurious trips of the EDG due to sensor failures, overall EDG reliability is increased.
3.
However, it is recognized that bypassing the high jacket water temperature trip does prevent automatic EDG trips that result from valid failures in the EDG cooling system. This, therefore, does represent a finite increase in the possibility of EDG damage and failure. The probability of a valid EDG failure (in the cooling water system) occurring coincident with an emer,ency start of the EDG is considered to be small. The risk of potential EDG damage in an emergency is acceptable given the availability of a redundant EDG and given the increased reliability of the EDG (prevention of spurious EDG failures stemming from jacket water temperature sensor failures) with the resultant enhancement to plant safety.
4.
Although there may be an increased potential for diesel generator damage due to loss of engine cooling (real failure) during emergency starts, the operating experience to date at Vogtle indicates that this potentiality is outweighed by the increased EDG reliability achieved and the commensurate benefit to overall plant safety.
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I have attached the Licensee's Request of May 25, 1990 To Revise Technical Specification 4.8.1.1.2h(6)(c), the Staffs SE and Reg Guide 1.9 Rev. 2 to my affidavit for additional information. It is the Staffs view that undoing or reversing the associated amendments to the technical specifications for the two Vogtle facilities would degrade the reliability of the EDGs and would not be in the interest of the public health and safety.
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'au d DAVID B. MAI niEWS Subscribed and sworn to before me this /Mday of September,1990 6bj
'GM<^Yh Notary Public j
cat *,t L. Atv.IUST; J'.3 NOTARY PVSUc IIATE Of mRYLAND My Comminim Empkn Jonvory 17.1994
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