ML20126G903

Advises That Proposed Delay to Provide Addl Time for Dialogue Re Value of Reactor Vessel Head Level Trend Sys Has Been Denied.Understanding Is That Installation Will Be Completed by End of Current Refueling Shutdown

ML20126G903
Person / Time
Site:	Crystal River
Issue date:	06/06/1985
From:	Stolz J Office of Nuclear Reactor Regulation
To:	Wilgus W FLORIDA POWER CORP.
References
TAC-57802, NUDOCS 8506180181
Download: ML20126G903 (5)

Text

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. JUN 0 61985 +)

Docket No. 50-302 DISTRIBUTION Joctet.ryfe i ACRS-10 NRC PDR RIngram '

L PDR HSilver Mr. Walter S. Wilgus ORB #4 Rdg Gray File Vice President, Nuclear Operations HThompson EBrach Florida Power Corporation OELD H0rnstein ATTN: Manager, Nuclear Licensing EJordan LRubenstein

& Fuel Management JPartlow P. O. Box 14042; M.A.C. H-2 St. Petersburg, Florida 33733

Dear Mr. Wilgus:

By letter dated August 31, 1984, you proposed delay of installation of the portion of the reactor coolant system water level instrumentation which connects to the reactor vessel head (reactor vessel head level trend system, or RVHLTS) until Refuel VI rather than Refuel V as previously committed, based on utilization of manpower and financial resources during Refuel V. In our letter dated October 10, 1984, we confirmed our previous verbal request for additional justification for this change.

Your letter of February 1,1985 stated that the purpose of the proposed delay is to provide additional time for dialogue with NRC regarding the value of the RVHLTS and whether it should be installed at all. You based your substantive argument primarily on the results of the Once Through Integral Systems (OTIS) tests performed in April and May of 1984, and concluded that the upper head level trending system is no longer needed since it has been demonstrated that hot leg gases can be removed and natural circulation cooling can be established by opening the high point vents on indication that the fuel clad temperature has reached 1400*F. You also point out that an upper, head bubble will not interfere with core cooling and that the subcooling margin based on core exit temperature will be a more reliable and earlier indicator for core cooling protection. The lack of accuracy of the upper head system is cited as a potential source of confusion to the operator. Negative '

safety effects and expense associated with the upper head system are also cited.

While some of your arguments have merit, they fail to recognize other considerations developed during the initial review, e.g., the purpose of the upper head inventory trending monitor is for indication of the approach to inadequate core cooling (core uncovering) and for monitoring the effectiveness of recovery operations such as emergency coolant injection or the cited venting operations. Under many circumstances, the upper head instrumentation will provide an earlier indication of coolant loss than the subcooling margin instrumentation. Operators should be trained regarding tbo accuracy of the instrument - the measurement is intended to trend coolant inventory, not to measure the level. Other adverse factors cited are not new information.

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l Mr. Wilgus '

In sumation, while you have cited new test data to support your position, we see no unexpected results or new information that would bear directly on the arguments already considered during the Commission review which led to issuance of the December 10, 1982 Order for FPC to install a coolant inventory trending system.

l Therefore, we do not concur with your requested deferral of installation of the RVHLTS. It is our understanding that you are presently proceeding with i the installation of this system and that the installation will be complete by the end of the current refueling shutdown.

Sincerely,

• c:aalut, sIcm Sr l

Khat R. snw,e l

John F. Stolz, Chief Operating Reactors Branch #4 Division of Licensing 1

cc: See next page l

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Mr. W. S. Wilgus Crystal River Unit No. 3 Nuclear Florida Power Corporation Generating Plant cc:

Mr. R. W. Neiser Bureau of Intergovernmental Relations Senior Vice President 660 Apalachee Parkway and General Counsel Tallahassee, Florida 32304 Florida Power Corporation P. O. Box 14042 Mr. Wilbur Langely, Chairman St Petersburg, Florida 33733 Board of County Comissioners Citrus County Nuclear Plant Manager Inverness jFlorida 36250 Florida Power Corporation P. O. Box 219 Crystal River, Florida 32629 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Power Generation Division Suite 220, 7910 Woodmont Avenue Bethesda, Maryland 20814 Mr. Tom Stetka, Resident Inspector U.S. Nuclear Regulatory Comission Route #3, Box 171 Crystal River, Florida 32629 Dr. J. Nelson Grace, Regional Administrator U.S. Nuclear Regulatory Comission, Region 11

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101 Marietta Street, Suite 3100 Atlanta, Georgia 30303 Mr. Ulray Clark, Administrator Radiological Health Services Department of Health and,

.: Rehabilitative Services 1323 Winewood-Blvd.

Tallahassee Florida 32301 Administrator s Department of Environmental Regulation Power Plant Siting Section State of Florida 2600 B1 air' Stone Road Tallahassee, Florida. 32301 Attorney General Department of Legal Affairs

.The Capitol Tallahassee, Florida 32304-r

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