Nonconservative Reactor Coolant System Leakage Calculation ML031070006 Person / Time Site:
Beaver Valley , Millstone , Hatch , Monticello , Calvert Cliffs , Dresden , Davis Besse , Peach Bottom , Browns Ferry , Salem , Oconee , Mcguire , Nine Mile Point , Palisades , Palo Verde , Perry , Indian Point , Fermi , Kewaunee , Catawba , Harris , Wolf Creek , Saint Lucie , Point Beach , Oyster Creek , Watts Bar , Hope Creek , Grand Gulf , Cooper , Sequoyah , Byron , Pilgrim , Arkansas Nuclear , Braidwood , Susquehanna , Summer , Prairie Island , Columbia , Seabrook , Brunswick , Surry , Limerick , North Anna , Turkey Point , River Bend , Vermont Yankee , Crystal River , Haddam Neck , Ginna , Diablo Canyon , Callaway , Vogtle , Waterford , Duane Arnold , Farley , Robinson , Clinton , South Texas , San Onofre , Cook , Comanche Peak , Yankee Rowe , Maine Yankee , Quad Cities , Humboldt Bay , La Crosse , Big Rock Point , Rancho Seco , Zion , Midland , Bellefonte , Fort Calhoun , FitzPatrick , McGuire , LaSalle , Fort Saint Vrain , Shoreham , Satsop , Trojan , Atlantic Nuclear Power Plant , Crane Issue date:
06/20/1994 From:
Grimes B Office of Nuclear Reactor Regulation To:
References IN-94-046 , NUDOCS 9406130222Download: ML031070006 (10)
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Beaver Valley ,
Millstone ,
Hatch ,
Monticello ,
Calvert Cliffs ,
Dresden ,
Davis Besse ,
Peach Bottom ,
Browns Ferry ,
Salem ,
Oconee ,
Mcguire ,
Nine Mile Point ,
Palisades ,
Palo Verde ,
Perry ,
Indian Point ,
Fermi ,
Kewaunee ,
Catawba ,
Harris ,
Wolf Creek ,
Saint Lucie ,
Point Beach ,
Oyster Creek ,
Watts Bar ,
Hope Creek ,
Grand Gulf ,
Cooper ,
Sequoyah ,
Byron ,
Pilgrim ,
Arkansas Nuclear ,
Braidwood ,
Susquehanna ,
Summer ,
Prairie Island ,
Columbia ,
Seabrook ,
Brunswick ,
Surry ,
Limerick ,
North Anna ,
Turkey Point ,
River Bend ,
Vermont Yankee ,
Crystal River ,
Haddam Neck ,
Ginna ,
Diablo Canyon ,
Callaway ,
Vogtle ,
Waterford ,
Duane Arnold ,
Farley ,
Robinson ,
Clinton ,
South Texas ,
San Onofre ,
Cook ,
Comanche Peak ,
Yankee Rowe ,
Maine Yankee ,
Quad Cities ,
Humboldt Bay ,
La Crosse ,
Big Rock Point ,
Rancho Seco ,
Zion ,
Midland ,
Bellefonte ,
Fort Calhoun ,
FitzPatrick ,
McGuire ,
LaSalle ,
Fort Saint Vrain ,
Shoreham ,
Satsop ,
Trojan ,
Atlantic Nuclear Power Plant ,
Crane Category:NRC Information Notice
[Table view] The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Mcguire]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] OR [[:Crane]] </code>.
Contents
1 NUCLEAR REGULATORY COMMISSION 2 June 20, 1994 3 Addressees 4 Purpose 5 Description of Circumstances
5.1 In particular, leakoff water from the cold leg 5.2 At that time, total leakage was 5.3 June 20, 1994 5.4 The licensee 5.5 Brian K. Grimes, Director 5.6 Office of Nuclear Reactor Regulation 5.7 George F. Maxwell, RII 5.8 John Zeiler, RII 5.9 Garry A. Harris, RII 5.10 List of Recently Issued NRC Information Notices 5.11 June 20, 1994 LIST OF RECENTLY ISSUED 5.12 Failure Mechanism for 5.13 Main Steam Isolation 5.14 Inadequate Maintenance 5.15 Generator Leak Rate 5.16 Region of the Core 5.17 Problems with General 5.18 Overload Relay Ambient 5.19 Failure of a Rod Control 5.20 Insert Following a Reactor 5.21 Identified Problems in 5.22 Radiosurgery 5.23 Inspection at Dresden 5.24 Unit 1 Following a Rupture 5.25 All holders of OLs or CPs 5.26 All holders of OLs or CPs 5.27 All holders of OLs or CPs 5.28 All holders of OLs or CPs 5.29 All holders of OLs or CPs 5.30 All holders of OLs or CPs 5.31 All U.S. Nuclear Regulatory 5.32 All holders of OLs or CPs 5.33 Brian K. Grimes, Director 5.34 Office of Nuclear Reactor Regulation 5.35 George F. Maxwell, RII 5.36 John Zeiler, RII 5.37 Garry A. Harris, RII 5.38 List of Recently Issued NRC Information Notices 5.39 Brian K. Grimes, Director 5.40 Office of Nuclear Reactor Regulation 5.41 George F. Maxwell, RII 5.42 John Zeiler, RII 5.43 Garry A. Harris, RII 5.44 List of Recently Issued NRC Information Notices 5.45 June xx, 1994 5.46 Brian K. Grimes, Director 5.47 Office of Nuclear Reactor Regulation 5.48 George F. Maxwell, RII 5.49 John Zeiler, RII 5.50 Garry A. Harris, RII 5.51 List of Recently Issued NRC Information Notices 5.52 May xx, 1994 5.53 Brian K. Grimes, Director 5.54 Office of Nuclear Reactor Regulation 5.55 George F. Maxwell, RII 5.56 John Zeiler, RII 5.57 Garry A. Harris, RII 5.58 List of Recently Issued NRC Information Notices 5.59 March xx, 1994 5.60 Brian K. Grimes, Director 5.61 Office of Nuclear Reactor Regulation 5.62 George F. Maxwell, RII 5.63 John Zeiler, RII 5.64 Gary A. Harris, RII 5.65 List of Recently Issued NRC Information Notices
NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON , D.C.
20555
June 20, 1994 NRC INFORMATION NOTICE 94-46: NONCONSERVATIVE REACTOR COOLANT SYSTEM LEAKAGE
CALCULATION
Addressees All holders of operating licenses or construction permits for nuclear power
reactors.
Purpose The U.S. Nuclear Regulatory Commission (NRC) is issuing this information
notice to alert addressees to the potential for water from sources other than
the reactor to be routed to closed system tanks inside the containment and
thus cause a nonconservative evaluation of unidentified reactor coolant system
leakage.
It is expected that recipients will review the information for
applicability to their facilities and consider actions, as appropriate, to
avoid similar problems.
However, suggestions contained in this information notice are not NRC requirements; therefore, no specific action or written
response is required.
Description of Circumstances McGuire Nuclear Station. On December 7, 1993, during review of the leakage
inputs into the reactor coolant drain tank, the licensee, Duke Power Company, determined that several valve stem leakoff lines other than those associated
with the reactor coolant system or the chemical and volume control system were
connected to the tank.
In particular, leakoff water from the cold leg accumulators and the refueling water storage tank was collected in the reactor
coolant drain tank. The connected cold leg accumulator leakoff lines included
the four nominal 10 in. discharge isolation valves, four nominal 1 in. fill
isolation valves, and seventeen nominal I in. or 1 in. isolation valves
associated with the test header for cold leg accumulator and safety injection
check valves . In addition, a discharge line from a relief valve on a flush
line to the regenerative heat exchanger was connected to the reactor coolant
drain tank.
Leakoff from these sources incorrectly increased the value of
identified RCS leakage, resulting in a nonconservative value of unidentified
leakage from the reactor coolant system (Licensee Event Report (LER)
50-369/94-01).
Upon discovery, the licensee conservatively labeled the measured total reactor
coolant system leakage as unidentified.
At that time, total leakage was calculated to be less than 3.8 1/min [1 gal/min]; therefore, the technical
specification limit of 3.8 1/min [1 gal/min] for unidentified leakage was not
exceeded.
At each unit, the licensee redirected these leakoff lines to the
containment sump and reevaluated unidentified leakage for the current
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IN 94-46
June 20, 1994 Page 2 OF 3 operating cycle. The licensee found the unidentified leakage to be no greater
than 4.9 1/min [1.3 gal/min] greater than previously evaluated.
The licensee concluded that some leakoff from the non-reactor sources had drained into the
reactor coolant drain tank at each unit and that the technical specification
limit for unidentified leakage had been exceeded several times during the
current operating cycle for Unit 2.
Catawba Nuclear Station. In a similar review, the licensee, also Duke Power
Company, determined that the leakoff lines from the four nominal 10-in. cold
leg accumulator discharge isolation valves were connected to the reactor
coolant drain tank. The licensee redirected these lines to the containment
sump , reevaluated operability, and determined that the technical specification
unidentified leakage limit had not been exceeded during the current operating
cycle.
Discussion
In a pressurized water reactor (PWR ), reactor coolant system leakage inside
containment is typically classified as "identified" or "unidentified."
Identified leakage includes the coolant leakage directed into closed system
tanks, such as the leakoff systems for the reactor coolant pumps or valves
routed to the reactor coolant drain tank and the leakoff systems for
pressurizer safety and relief valves routed to the pressurizer relief tank.
All other leakage is labeled "unidentified."
The licensee assigned the cause of the McGuire event to failure in the
original design of the computer program for calculating reactor coolant system
leakage to recognize inputs of water from other systems to the reactor coolant
drain tank.
Most PWR leakage detection calculations use measurements of
changes in the reactor coolant system inventory over a specified time period.
The total leakage is obtained from the sum of subsidiary inventory changes, such as changes in the inventories of the volume control tank and of the
pressurizer. The identified leakage component is determined from changes in
the closed system inventory, and the unidentified component is then determined
by subtracting the identified leakage from the total leakage.
Typical
technical specifications for PWRs , as is the case here, set the limiting
condition for operation for unidentified leakage at 3.8 I/min [1 gal/min] and
stipulate periodic determinations of this leakage.
IN 94-46 June 20, 1994 This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation project manager.
Brian K. Grimes, Director Division of Operating Reactor Support
Office of Nuclear Reactor Regulation Technical contacts:
George F. Maxwell, RII (704) 875-1681
John Zeiler, RII (803) 831-2963
Garry A. Harris, RII (704) 875-1682 Attachment:
List of Recently Issued NRC Information Notices A tachment
IN 94-46
June 20, 1994 LIST OF RECENTLY ISSUED NRC INFORMATION NOTICES
Information
Date of
Notice No.
Subject
Issuance
Issued to
94-45
94-44
94-43
94-42
94-41 Potential Common-Mode
Failure Mechanism for Large Vertical Pumps
Main Steam Isolation Valve Failure to Close
on Demand because of
Inadequate Maintenance and Testing
Determination of Primary- to-Secondary Steam
Generator Leak Rate Cracking in the Lower
Region of the Core Shroud in Boiling-Water
Reactors
Problems with General Electric Type CR124
Overload Relay Ambient Compensation
Failure of a Rod Control Cluster Assembly to Fully
Insert Following a Reactor Trip at Braidwood Unit 2
Identified Problems in Gamma Stereotactic
Radiosurgery Results of a Special NRC
Inspection at Dresden Nuclear Power Station
Unit 1 Following a Rupture of Service Water Inside
Containment
06/17/94
06/16/94
06/10/94
06/07/94
06/07/94
05/26/94
05/31/94
05/27/94
All holders of OLs or CPs for nuclear power reactors.
All holders of OLs or CPs for nuclear power reactors.
All holders of OLs or CPs for pressurized water
reactors.
All holders of OLs or CPs for boiling-water reactors
(BWRs ).
All holders of OLs or CPs for nuclear power reactors.
All holders of OLs or CPs for pressurized-water
reactors (PWRs ).
All U.S. Nuclear Regulatory Commission Teletherapy
Medical Licensees.
All holders of OLs or CPs for NPRs and all fuel cycle
and materials licensees
authorized to possess spent
fuel.
94-40
94-39
94-38 OL = Operating License
CP = Construction Permit
IN 94-46 June 20, 1994 This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation project manager.
Brian K. Grimes, Director Division of Operating Reactor Support
Office of Nuclear Reactor Regulation Technical contacts:
George F. Maxwell, RII (704) 875-1681
John Zeiler, RII (803) 831-2963
Garry A. Harris, RII (704) 875-1682 Attachment:
List of Recently Issued NRC Information Notices OFFICE
NAME
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DATE
03/07/94
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June xx, 1994 This information notice requires no specific action or written response. If
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Nuclear Reactor Regulation project manager.
Brian K. Grimes, Director Division of Operating Reactor Support
Office of Nuclear Reactor Regulation Technical Contacts:
George F. Maxwell, RII (704) 875-1681
John Zeiler, RII (803) 831-2963
Garry A. Harris, RII (704) 875-1682 Attachment:
List of Recently Issued NRC Information Notices OFFICE
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Brian K. Grimes, Director Division of Operating Reactor Support
Office of Nuclear Reactor Regulation Technical Contacts:
George F. Maxwell, RII (704) 875-1681
John Zeiler, RII (803) 831-2963
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one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation project manager.
Brian K. Grimes, Director Division of Operating Reactor Support
Office of Nuclear Reactor Regulation Technical Contacts:
George F. Maxwell, RII (704) 875-1681
John Zeiler, RII (803) 831-2963
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one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation project manager.
Brian K. Grimes, Director Division of Operating Reactor Support
Office of Nuclear Reactor Regulation Technical Contacts:
George F. Maxwell, RII (704) 875-1681
John Zeiler, RII (803) 831-2963
Gary A. Harris, RII (704) 875-1682 Attachment:
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list Information Notice 1994-01, Turbine Blade Failures Caused by Torsional Excitation from Electrical System Disturbance 7 January 1994 Information Notice 1994-02, Inoperability of General Electric Magne-Blast Breaker Because of Misalignment of Close-Latch Spring 7 January 1994 Information Notice 1994-03, Deficiencies Identified During Service Water System Operational Performance Inspections 11 January 1994 Topic Biofouling Information Notice 1994-04, Digital Integrated Circuit Sockets with Intermittent Contact 14 January 1994 Information Notice 1994-05, Potential Failure of Steam Generator Tubes with Kinetically Welded Sleeves 19 January 1994 Topic Stress corrosion cracking Information Notice 1994-06, Potential Failure of Long-Term Emergency Nitrogen Supply for the Automatic Depressurization System Valves 28 January 1994 Information Notice 1994-07, Solubility Criteria for Liquid Effluent Releases to Sanitary Sewerage Under the Revised 10 CFR Part 20 28 January 1994 Information Notice 1994-08, Potential for Surveillance Testing to Fail to Detect an Inoperable Main Steam Isolation Valve 1 February 1994 Information Notice 1994-09, Release of Patients with Residual Radioactivity from Medical Treatment & Control of Areas Due to Presence of Patients Containing Radioactivity Following Implementation of Revised 10 CFR Part 20 3 February 1994 Topic Brachytherapy Information Notice 1994-10, Failure of Motor-Operated Valve Electric Power Train Due to Sheared or Dislodged Motor Pinion Gear Key 4 February 1994 Information Notice 1994-11, Turbine Overspeed and Reactor Cooldown During Shutdown Evolution 8 February 1994 Topic Overspeed trip Overspeed Information Notice 1994-12, Insights Gained from Resolving Generic Issue 57: Effects of Fire Protection System Actuation on Safety-Related Equipment 9 February 1994 Topic Loss of Offsite Power Overspeed Information Notice 1994-13, Unanticipated and Unintended Movement of Fuel Assemblies and Other Components Due to Improper Operation of Refueling Equipment 28 June 1994 Topic Spent fuel rack Information Notice 1994-14, Failure to Implement Requirements for Biennial Medical Examinations and Notification to the NRC of Changes in Licensed Operator Medical Conditions 24 February 1994 Topic Overspeed Information Notice 1994-15, Radiation Exposures During an Event Involving a Fixed Nuclear Gauge 2 March 1994 Topic Overspeed Information Notice 1994-16, Recent Incidents Resulting in Offsite Contamination 3 March 1994 Topic Overspeed Information Notice 1994-17, Strontium-90 Eye Applicators: Submission of Quality Management Plan (QMP), Calibration, and Use 11 March 1994 Topic Brachytherapy Overspeed Information Notice 1994-17, Strontium-90 Eye Applicators: Submission of Quality Management Plan (Qmp), Calibration, and Use 11 March 1994 Topic Brachytherapy Overspeed Information Notice 1994-18, Accuracy of Motor-Operated Valve Diagnostic Equipment (Responses to Supplement 5 to Generic Letter 89-10) 16 March 1994 Information Notice 1994-19, Emergency Diesel Gemerator Vulnerability to Failure from Cold Fuel Oil 16 March 1994 Information Notice 1994-20, Common-Cause Failures Due to Inadequate Design Control and Dedication 17 March 1994 Information Notice 1994-21, Regulatory Requirements When No Operations Are Being Performed 18 March 1994 Topic Inactive license Information Notice 1994-22, Fire Endurance & Ampacity Derating Test Results for 3-Hour Fire-Rated Thermo-Lag 330-1 Fire Barriers 16 March 1994 Topic Fire Barrier Information Notice 1994-23, Guidance to Hazardous, Radioactive and Mixed Waste Generators on the Elements of a Waste Minimization Program 25 March 1994 Information Notice 1994-24, Inadequate Maintenance of Uninterruptible Power Supplies & Inverters 24 March 1994 Topic Safe Shutdown Information Notice 1994-25, Failure of Containment Spray Header Valve to Open Due to Excessive Pressure from Inertial Effects of Water 15 March 1994 Topic Water hammer Information Notice 1994-26, Personnel Hazards and Other Problems from Smoldering Fire-Retardant Material in the Drywell of a Boiling-Water Reactor 28 March 1994 Information Notice 1994-27, Facility Operating Concerns Resulting from Local Area Flooding 31 March 1994 Information Notice 1994-28, Potential Problems with Fire-Barrier Penetration Seals 5 April 1994 Topic Fire Barrier Operability Determination Information Notice 1994-29, Charging Pump Trip During a Loss-of-Coolant Event Caused by Low Suction Pressure 11 April 1994 Topic Boric Acid Information Notice 1994-30, Leaking Shutdown Cooling Isolation Valves at Cooper Nuclear Station 19 August 1994 Topic Fire Barrier Local Leak Rate Testing Information Notice 1994-31, Potential Failure of Wilco, Lexan-Type HN-4-L Fire Hose Nozzles 14 April 1994 Topic Hydrostatic Information Notice 1994-32, Revised Seismic Estimates 29 April 1994 Topic Stress corrosion cracking Earthquake Information Notice 1994-33, Capacitor Failures in Westinghouse Eagle 21 Plant Protection Systems 9 May 1994 Topic Stress corrosion cracking Information Notice 1994-34, Thermo-LAG 330-660 Flexi-Blanket Ampacity Derating Concerns 13 May 1994 Topic Fire Barrier Stress corrosion cracking Information Notice 1994-35, Niosh Respirator User Notices, Inadvertent Separation of the Mask-Mounted Regulator(Mmr) from the Facepiece on the Mine Safety Appliances 16 May 1994 Topic Stress corrosion cracking Information Notice 1994-35, Niosh Respirator User Notices, Inadvertent Separation of the Mask-Mounted Regulator(MMR) from the Facepiece on the Mine Safety Appliances 16 May 1994 Information Notice 1994-36, Undetected Accumulation of Gas in Reactor Coolant System 24 May 1994 Topic Reactor Vessel Water Level Stress corrosion cracking Integrated leak rate test Gas accumulation Information Notice 1994-37, Misadministration Caused by a Bent Interstitial Needle During Brachytherapy Procedure 27 May 1994 Topic Stress corrosion cracking Brachytherapy Information Notice 1994-38, Results of Special NRC Inspection at Dresden Nuclear Power Station, Unit 1 Following Rupture of Service Water Inside Containment 27 May 1994 Information Notice 1994-39, Identified Problems in Gamma Stereotactic Radiosurgery 31 May 1994 Information Notice 1994-40, Failure of a Rod Control Cluster Assembly to Fully Insert Following a Reactor Trip at Braidwood, Unit 2 26 May 1994 Information Notice 1994-41, Problems with General Electric Type CR124 Overload Relay Ambient Compensation 7 June 1994 Information Notice 1994-42, Cracking in the Lower Region of the Core Shroud in Boiling-Water Reactors 7 June 1994 Topic Stress corrosion cracking Information Notice 1994-43, Determination of Primary-to-Secondary Steam Generator Leak Rate 10 June 1994 Topic Grab sample Main Steam Line Radiation Monitor Information Notice 1994-44, Main Steam Isolation Valve Failure to Close on Demand Because of Inadequate Maintenance and Testing 16 June 1994 Information Notice 1994-44, Main Steam Isolation Valve Failure to Close on Demand because of Inadequate Maintenance and Testing 16 June 1994 Information Notice 1994-45, Potential Common-Mode Failure Mechanism for Large Vertical Pumps 17 June 1994 Topic Biofouling Information Notice 1994-46, Nonconservative Reactor Coolant System Leakage Calculation 20 June 1994 Topic Unidentified leakage Information Notice 1994-47, Accuracy of Information Provided to NRC During the Licensing Process 21 June 1994 ... further results
