ML19310A389
| ML19310A389 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 06/06/1980 |
| From: | Richard Bright FLORIDA POWER CORP. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-80-12, NUDOCS 8006110185 | |
| Download: ML19310A389 (5) | |
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Florida Power C 0 A 70 4 a f 90 as June 6, 1980 File: 3-0-3-a-4 Mr. J. P. O'Reilly Director U.S. Nuclear Regulatory Commission Office of Inspection and Enforcement Suite 3100 101 Marietta Street Atlanta, GA 30303
Subject:
Crystal River Unit 3 Docket No. 50-302 Operating License No. DPR-72 I.E.Bulletin 80-12 DECAY HEAT REMOVAL SYSU." OPERABILITY
Dear Mr. O'Reilly:
Enclosed is our response to I.E.Bulletin 80-12.
Please contact this office if you require any additional discussion concerning our response.
Very truly yours, FLORIDA POWER CORPORATION R. M. Bright Acting Manager Nuclear Support Services Enclosure Lobo (IE80-12)DN86 cc: Director g/
Division of Reactor Operations Inspection NRC Office of Inspection and Enforcement j
Washington, DC '2G555 l /
General Office 320s ininy iounn sueet soutn. p o Box 14042. st Petersburg. F!orica 33731 813-866 515I 80'O611 Oi g[i.
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FPC RESPONSE TO I.E. BULLETIN 80-12 Item 1:
" Review the circumstances and sequence of events at Davis-Besse as described in Enclosure 1."
Response
Fiorida Power Corporation engineering has reviewed IE Information Notice 80-20 for applicability to CR-3.
In addition, the subject Information Notice will be reviewed with plant personnel during retraining periods.
Item 2:
"Ruiew your facility (ies) for all DHR degradation events experienced, especially for events similar to the Davis-Besse incident."
Response
A review of CR-3 Licensee Event Reports for loss of Decay Heat Removal capability found that 5 LER's had been initiated on this subject (Nos. 77-90,77-101, 79-022,79-046, and 80-015).
These identified losses of DH capability were all as a result of DHV-3 or 4 not opening from the Control Board or due to Egineered Safeguards (ES) actuation during performance of Functional Tests.
The valves that would not open remotely were manually overridden and subsequently tested satisfactorily.
It is noted that CR-3 ES logic is 2 out of 3 taken twice vice 2 out of 4 taken once as at Davis-Besse Unit 1.
In addition, CR-3 does not have an autnmatic alignment to the RB sump for LPI recirculation mode on low BWST level. Therefore, the BWST could not be drained to the RS sump due to automatic actuation.
Item 3:
" Review the hardware capability of your facility (ies) to prevent DHR loss events, including equipment redundancy, diversity, powe-source reliability, instrumentation and control reliability, and overall reliability during refueling and cold shutdown modes of operation."
Response
Florida Power Corporation engineering has reviewed the various systems at CR 3 which provide decay heat removal of the core during the cold shutdown and refueling modes of operation.
During normal cold shutdown and refueling. operations, decay heat is removed by the Decay Heat Removal System (DH) which is comprised of two redundant trains, each capable of 100'. removal
-Lobo (IE80-12)DN86 t
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Item 3 Response (Cont'd) of the decay heat.
The DH system has been reviewed and determined to be electrically and mechanically redundant.
Power supply to each. train is separate and includes alternate diesel generator back-up.
The piping systems
,aaintain total segregation, with the exception of the suction piping which share a comon dropline off the RCS hot leg. However, diversity exists on the suction piping, allowing line up from the Barated Water Storage Tank, Reactor Building Sump, Spent Fuel Pool or Fuel Transfer Canal.
With loss of both DH trains, alternate methods of decay heat removal exist (see response to Item 4) thereby, p*oviding redundancy, diversity and reliability.
Item 4:
" Analyze your irocedures for adequacy of safeguarding against loss of redundan:y and diversity for DHR capability."
Response
A thorough analysis of EP-112 " Loss of Decay Heat Removal System" has been accomplished.
EP-112 is an entirely new procedure approved by the Plant Review Comittee (PRC) on 5/14/80.
This ne,' procedure incorporates guidelines established by B&W document numbe r 69-1106921-00. Redundant means of decay heat removal are addressed in EP-112. These redundant means include utilizing the alternate DH train, Low Pressure Inj ection,
High Pressure In,iection, Waste Disposal Pumps, Spent Fuel Cooling System, normal cooldown and natural circulation cooldown.
In addition, OP-404 " Decay Heat Removal System" and AI-500 " Conduct of Operations" have been changed to establish administrative requirements to be met prior to removing a DH Train from service.
Item 5:
" Analyze your procedures for adequacy of responding to DHR loss events.
Special emphasis should be placed upon responses when maintenance or refueling activities degrade the DHR capability."
Response
i In addition to the items listed in response to Item 4 above, OP-404
" Decay Heat Removal System" has been changed to incorporate requirements to:
a) trip DH pumps when suction valves are not open, b) lock out breakers during periods when Reactor Vessel Head is removed to prevent spurious closing of drop line valves due to erroneous signal, and c) isolate the BWST when level is low and the BAST is being utilized for emergency boration inventory.
Lobo (IE80-12)DN86
Item 6:
"Until further notice or until Technical Specifications are revised to resolve the issues of this Bulletin, you should:
a.
Implement as soon as practicable administrative controls to assure that redundant or diverse DHR methods are available during all modes of plant operation; (Note:
When in a refueling mode with water in the refueling cavity and the head removed, an acceptable means could include one DHR train and a readily accessible source of barated water to repler:ish any loss of inventory that might occur subsequent to the loss of the available DHR train.)
b.
Implement administrative controls as soon as practicable, for those cases where single failures or other actions can result in only one DHR train being i
available, requiring an alternate means of DHR or expediting the restoration of the lost train or method.
Response to 6.a.:
OP-404 " Decay Heat Removal Sy stem" and AI-500 " Conduct of Operations" have been changed to implement administrative controls to assure that redundant or diverse DHR methods are available during all modes of plant operation.
Response to 6.b.:
AI-500 " Conduct of Operations" has been revised to establish administrative control s to be followed prior to voluntarily entering a degraded mode of operation.
Item 7:
" Report to-the NRC within 30 days of the date of this Bulletin the results of the above reviews and analyses, describing:
a.
Changes to procedures (e.g.,
emergency, operational, administrative, maintenance, refueling) made or initiated as a result of your reviews and analyses, including the scheduled or actual dates of accomplishment; (Note: NRC suggests that you conisder 4
the - following: (1) limiting maintenance activities to assure redundancy or diversity and integrity of DHR capability, and (2) bypassing or disabling, where applicable, automatic actuation of ECCS recirculation in addition to disabling High Pressure Injection. and Containment Spray. preparatory to the cold shutdown or refueling mode.)
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Item 7 (Cont'd) b.
The safeguards at your facility (ies) against DHR degradation, including your assessment of their adequacy."
Response to 7.a.:
(1) Limiting activities to assure redundalqy or diversity and integrity of systems is addressed in EP-112, OP-404, and AI-500 as discussed above.
(2) HPI is presently disabled during DHR.
This disabling of HPI removes the initiation signal for Containment Spray.
In addition, there is no automatic ECCS recirculation actuation. This is further discussed in the response to Item 2 above.
Response to 7.b.:
A thorough review of safeguards and procedures app'icable to CR-3 was undertaken by operations department engineers and it is felt that current methods of Decay Heat Removal at CR-3 are adequate.
1 Loo (IE80-12)Dil86
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