ML18106B077
| ML18106B077 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 02/24/1999 |
| From: | Milano P NRC (Affiliation Not Assigned) |
| To: | Keiser H Public Service Enterprise Group |
| References | |
| NUDOCS 9903030004 | |
| Download: ML18106B077 (12) | |
Text
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February 2 4, 1 9-9 9 e
Mr. Harold W. Keiser Chief Nuclear Officer & President-Nuclear Business Unit Public Service Electric & Gas Company Post Office Box 236 Hancocks Bridge, NJ 08038
SUBJECT:
CHANGES TO TECHNICAL SPECIFICATION BASES, SALEM NUCLEAR GENERATING STATION, UNIT NOS. 1AND2
Dear Mr. Keiser:
In letters dated June 17, 1998, and January 22, 1999, the Public Service Electric and Gas Company (licensee) provided to the U.S. Nuclear Regulatory Commission (NRC) several revised Technical Specification (TS) Bases sections for the Salem Nuclear Generating Station, Unit Nos. 1 and 2. The TS Bases that were revised included: (1) 3/4.1.2, "Boration Systems,"
(2) 3/4.1.3, "Moveable Control Assemblies" (for Salem Unit 1 only), (3) 3/4.5.5, "Refueling Water Storage Tank," and (4) 3/4.9.1, "Boron Concentration."
The NRC staff has reviewed the TS Bases changes and has no objection to the changes. The enclosed TS pages are being distributed for inclusion in the Salem Unit 1 and 2 TSs.
Docket Nos. 50-272 and 50-311
Enclosures:
Revised TS Pages cc w/encls: See next page DISTRIBUTION Docket File PUBLIC PDl-2 Reading JZwolinski EAdensam PMilano TClark OFFICE NAME OGC ACRS GHill(4)
WBeckner JWermiel GMeyer, RGN-1 PDl-2/LA TC lark~
Sincerely, original signed by:
Patrick D. Milano, Senior Project Manager Project Directorate 1-2 Division of Licensing Project Management Office of Nuclear Reactor Regulation DATE
/ "2:3 /98
~ I / '1, /98
/98 OFFICIAL RECORD COPY DOCUMENT NAME: SABASES.LTR 9903030004 990224 PDR ADOCK 05000272 P
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UNITED STATES NUCLEAR REGULATORY COMMISSION Mr. Harold W. Keiser Chief Nuclear Officer & President-Nuclear Business Unit Public Service Electric & Gas Company Post Office Box 236 Hancocks Bridge, NJ 08038 WASHINGTON, D.C. 20555--0001 February 24, 1999
SUBJECT:
CHANG.ES TO TECHNICAL SPECIFICATION BASES, SALEM NUCLEAR GENERATING STATION, UNIT NOS. 1AND2 Dear Mr. Keiser.
In letters dated June 17, 1998, and January 22, 1999, the Public Service Electric and Gas Company (licensee) provided to the U.S. Nuclear Regulatory Commission (NRC) several revised Technical Specification (TS) Bases sections for the Salem Nuclear Generating Station, Unit Nos. 1 and 2. The TS Bases that were revised included: (1) 3/4.1.2, "8,0ration Systems,"
(2) 3/4.1.3, "Moveable Control Assemblies" (for Salem Unit 1 only), (3) 3/4.5.5, "Refueling Water Storage Tank," and (4) 3/4.9.1, "Boron Concentration."
The NRC staff has reviewed the TS Bases changes and has no objection to the changes. The enclosed TS pages are being distributed for inclusion in the Salem Unit 1 and 2 TSs.
Docket Nos. 50-272 *and 50-311
Enclosures:
Revised TS Pages cc w/encls: See next page Sincerely, Patrick D. Milano, Senior Project Manager Project Directorate 1-2 Division of Licensing Project Management Office of Nuclear Reactor Regulation
Mr. Harold W. Keiser Public Service Electric & Gas Company cc:
Jeffrie J. Keenan, Esquire Nuclear Business Unit - N21 P.O. Box236 Hancocks Bridge, NJ 08038 General Manager - Salem Operations Salem Nuclear Generating Station P.O. Box236 Hancocks Bridge, NJ 08038 Mr. Louis Storz Sr. Vice President - Nuclear Operations Nuclear Department P.O. Box 236
- Hancocks Bridge, NJ 08038 Senior Resident Inspector Salem Nuclear Generating Station U.S. Nuclear Regulatory Commission Drawer0509 Hancocks Bridge, NJ 08038 Dr. Jill Lipoti, Asst. Director Radiation Protection Programs NJ Department of Environmental Protection and Energy CN 415 Trenton, NJ 08625-0415 Maryland Office of People's Counsel 6 St. Paul Street, 21st Floor
- Suite 2102 Baltimore, MD 21202 Ms. R. A. Kankus Joint Owner Affairs PECO Energy Company 965 Chesterbrook Blvd., 63C-5 Wayne, PA 19087 Mr. Elbert Simpson Senior Vice President-Nuclear Engineering Nuclear Department P.O. Box236 Hancocks Bridge, NJ 08038 Salem Nuclear Generating Station, Units 1and2 Richard Hartung Electric Service Evaluation*
Board of Regulatory Commissioners
- 2 Gateway Center, Tenth Floor Newark, NJ 07102 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Lower Alloways Creek Township c/o Mary 0. Henderson, Clerk Municipal Building, P.O. Box 157 Hancocks Bridge, NJ 08038 Director - Licensing Regulation & Fuels Nuclear Busienss Unit - N21 P.O. Box236 Hancocks Bridge, NJ 08038 Mr. David Wersan Assistant Consumer Advocate Office of Consumer Advocate 1425 Strawberry Square Harrisburg, PA 17120 Manager - Joint Generation Atlantic Energy 6801 Black Horse Pike Egg HarborTwp., NJ 08234-4130 Carl D. Schaefer External Operations - Nuclear Delmarva Power & Light Company P.O. Box231 Wilmington, DE 19899 Public Service Commission of Maryland Engineering Division Chief Engineer 6 St. Paul Centre Baltimore, MD 21202-6806
REACTIVITY CONTROL SYSTEMS BASES 3/4.1.2 BORATION SYSTEMS The boron injection system ensures that negative reactivity control is available during each mode of facility operation.
The components required to perform this function include:
- 1) borated water sources, 2) charging pumps,
- 3) separate flow paths, 4) boric acid transfer pumps, and 5) an emergency power supply from OPERABLE diesel generators.
With the RCS average temperature ~ 350°F, a minimum of two boron injection flow paths are required to ensure single functional capability in the event an assumed failure renders one of the flow paths inoperable.
The boration capability of either flow path is sufficient to provide ~ SHUTDOWN MARGIN from expected operating conditions of 1.3% delta k/k after xenon decay and cooldown to 200°F.
The maximum expected boration capability (minimum boration volume) requirement is established to conservatively bound expected operating conditions throughout core operating life.
The analysis assumes that the most reactive control rod is not inserted into the core. The maximum expected boration capability requirement occurs at EOL from full power equilibrium xenon conditions and requires borated water from a boric acid tank in accordance with TS Figure 3.1-2, and additional makeup from either:
('1) the second boric acid tank and/or batching, or (2) a maximum of 41,800 gallons of 2,300 ppm borated water from the refueling water storage tank.
With the refueling water storage tank as the only borated water source, a maximum of 73,800 gallons of 2,300 ppm borated water is required.
However, to be consistent with the ECCS requirements, the RWST is required to have a minimum contained volume of 364,500 gallons during operations in MODES 1, 2, 3 and 4.
The boric acid tanks, pumps, valves, and piping contain a boric acid solution concentration of between 3.75% and 4.0% by weight.
To ensure that the boric acid remains in solution, the tank fluid temperature and the process pipe wall temperatures are monitored to ensure a temperature of 63°F, or above is maintained.
The tank fluid and pipe wall temperatures are monitored in the main control room.
A 5°F margin is provided to ensure the boron will not precipitate out.
Should ambient temperature decrease below 63°F, the boric acid tank heaters, in conjunction with boric acid pump recirculation, are capable of maintaining the boric acid in the tank and in the pump at or above 63°F.
A small amount of boric acid in the flow path between the boric acid recirculation line and the suction line to the charging pump will precipitate out, but it will not cause flow blockage even with temperatures below 50°F."
With the RCS temperature below 350°F, one injection system is acceptable without single failure consideration on the basis of the stable reactivity condition of the reactor and the additional restrictions prohibiting CORE ALTERATIONS and positive reactivity change in the event the single injection system becomes inoperable.
SALEM - UNIT 1 B 3/4 1-3 JANUARY 19, 1999 Revised by NRC letter dated
REACTIVITY CONTROL SYSTEMS BASES 3/4.1.2 BORATION SYSTEMS The boron injection system ensures that negative reactivity control is available during each mode of facility operation.
The components required to perform this function include:
- 1) borated water sources, 2) charging pumps,
- 3) separate flow paths, 4) boric acid transfer pumps, and 5) an emergency power supply from OPERABLE diesel generators.
With the RCS average temperature ~ 350°F, a minimum of two boron injection flow paths are required to ensure single functional capability in the event an assumed failure renders one of the flow paths inoperable.
The boration capability of either flow path is sufficient to provide a SHUTDOWN MARGIN from expected operating conditions of 1.6% delta k/k after xenon decay and cooldown
. to 200°F.
The maximum expected boration capability (minimum boration volume) requirement is established to conservatively bound expected operating conditions throughout core operating life.
The analysis assumes that the most reactive control rod is not inserted into the core.
The maximum expected boration capability requirement occurs at EOL from full power equilibrium xenon conditions and requires borated water from a boric acid tank in accordance with TS Figure 3.1-2, and additional makeup from either:
(1) the second boric acid tank and/or batching, or (2) a maximum of 41,800 gallons of 2,300 ppm borated water from the refueling water storage tank.
With the refueling water storage tank as the only borated water source, a maximum of 73,800 gallons of 2,300 ppm borated water is required.
However, to be consistent with the ECCS requirements, the RWST is required to have a minimum contained volume of 364,500 gallons during operations in MODES 1, 2, 3 and 4.
The boric acid tanks, pump~, valves, and piping contain a boric acid solution concentration of between 3.75% and 4% by weight.
To ensure that the boric acid remains in solution, the tank fluid temperature and the process pipe wall temperatures are monitored to ensure a temperature of 63°F, or above is maintained.
The tank fluid and pipe wall temperatures are monitored in the main control room.
A 5°F margin is provided to ensure _the boron will not precipitate out.
Should ambient temperature decrease below 63°F, the boric acid tank heaters, in conjunction with boric acid pump recirculation, are capable of maintaining the boric acid in the tank and in the pump at or about 63°F.
A small amount of boric acid in the flowpath between the boric acid recirculation line and the suction line to the charging pump will precipitate out, but it will not cause flow blockage even with temperatures below 50°F.
With the RCS temperature below 350°F, one injection system is acceptable without single failure consideration on the basis of the stable reactivity condition of the reactor and the additional restrictions prohibiting CORE OPERATIONS and positive reactivity change in the event the single inject.ion system becomes inoperable.
SALEM - UNIT 2 B 3/4 1-3 JANUARY 19, 1999 Revised by NRC letter dated
REACTIVITY CONTROL SYSTEMS BASES The boron capability required below 200 °F in sufficient to provide a SHUTDOWN.
MARGIN of 1% delta k/k after xenon decay and cooldown from 200 °F to 140.°F.
This condition requires either 2,600 gallons of 6,560 ppm borated water from the boric acid storage tanks or 7,100 gallons of 2,300 ppm borated water from the refueling water storage tank..
The 37,000 gallons limit in the refueling water storage tank for Modes 5 and 6 is based upon 21,210 gallons that is undetectable due to lower tap location, 8,550 gallons for instrument error, 7,100 gallons required for shutdown margin, and an additional 140 gallons due to rounding up.
The limits on contained water volume and boron concentration of the RWST also ensure a pH value of between 7.0 and 10.0 for the solution recirculated within containment after a LOCA.
This pH band minimizes the evolution of iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.
The contained water volume limits include allowance for water not available because of discharge line location and other physical characteristics.
The OPERABILITY of one boron injection system during REFUELING ensures that this system is available for reactivity control while in MODE 6.
3/4.1.3 MOVABLE CONTROL ASSEMBLIES The specifications of this section ensure that (1) acceptable power distribution limits are maintained, (2) the minimum SHUTDOWN MARGIN is maintained, and (3) limit the potential effects of rod mis-alignment on associated accident analyses.
OPERABILITY of the control rod position indicators is required to determine control rod positions and thereby ensure ompliance with the control rod alignment and insertion limits.
OPERABLE condition for the analog rod position indicators is defined as being capable of indicating rod position to within the allowed rod misalignment relative to the bank demand position for a range of positions.
For the Shutdown Banks and Control Bank A this range is defined as the group demand counter indicated position between O and 30 steps withdrawn inclusive, and between 200 and 228 steps withdrawn inclusive. This permits the operator to verify that the control rods in these Banks are either fully withdrawn or fully inserted, the normal operating modes for these banks.
Knowledge of these banks positions in these ranges satisfies all accident analysis assumptions concerning their position.
The range for control Bank B is defined as the group demand counter indicated position between O and 30 steps withdrawn inclusive, and between_l60 and 228 steps withdrawn inclusive.
For Control Banks C and D the range is, defined as the group demand counter indicated position between O and 228 steps, withdrawn.
Comparison of the group demand counters to the bank insertion limits with verification of rod position with the analog rod position indicators (after thermal soak after rod motion) is sufficient verification that the control rods are above the insertion limits.
The full out position will be specifically established for each cycle by the Reload Safety Analysis for that cycle.
This position will be within the band established by "FULL WITHDRAWN" and will be administratively controlled.
This band is allowable to minimize RCCA wear, pursuant to Information Notice 87-19.
SALEM - UNIT 1 B 3/4 1-4 April 29, 1998 Revised by NRC letter dated
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REACTIVITY CONTROL SYSTEMS BASES
==================================================================
The ACTION statements which permit limited variation from the basic requirements are accompanied by additional restrictions which ensure that the original criteria are met.
Mis-alignment of a rod requires measurement of peaking factors or a restriction in THERMAL POWER; either of these restrictions provide assurance of fuel rod integrity during ~ontinued operation.
The reactivity worth of a mis-aligned rod is limited for the remainder of the fuel cycle to prevent exceeding the assumption used in the accident analysis.
The maximum rod drop time restriction is consistent with the assumed rod drop time used in the accident analyses.
Measurement with Tavg >541°F and with all reactor coolant pumps operating ensures that the measured drop times will be representative of insertion times experienced during a reactor trip at operating conditions.
Control rod positions _and OPERABILITY of the rod position indicators are required to be verified on a nominal basis of once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> with more frequent verifications required if an automatic monitoring channel is inoperable.
These verification frequencies are adequate for assuring that the applicable LCO's are satisfied.
The terms "Shutdown Rod Position Indicator", "Analog Rod Position Indicator", "Control Rod Position Indicator", and Rod Position Indicator" are all used* in this bases section or in the Technical Specifications, and all refer to indication driven by the output of the Analog Rod Position Indication (ARPI) system.
One method for determining rod position are the indicators on the control console.
An alternate method of determining rod position is the plant computer.
Either the control console.indicator or plant computer is sufficient to comply with this specification.
The plant computer receives the same input from ARPI as the control console indicators and provides resolution equivalent to or better than the control console indicators.
The plant computer also provides a digital readout of rod position which eliminates interpolation and parallax errors inherent.to analog scales.
SALEM - UNIT 1 B 3/4 1-5 April 7, 1998 Revised by NRC letter dated
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EMERGENCY £ORE COOLING SYSTEMS BASES requirement produces the conditions necessary to correctly set the manual throttle valves.
The exemption is limited to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to ensure timely surveillance completion once the necessary conditions are established.
3/4.5.5 REFUELING WATER STORAGE TANK The OPERABILITY of the RWST as part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECCS in the event of a LOCA.
The limits on RWST minimum volume and boron concentration ensure that:
(1) sufficient water is available. within containment to permit recirculation cooling flow to the core, (2) the reactor will remain subcritical in the cold condition following a small LOCA assuming complete mixing of the RWST, RCS, and ECCS water volumes with all control rods inserted except the most reactive control assembly (ARI-1), and (3).the reactor will remain subcritical in the cold condition following a large break LOCA (break flow area > 3.0 sq. ft.)
assuming complete mixing of the. RWST, RCS, and ECCS water and other sources of water that may eventually reside in the sump following a LOCA with all control rods assumed to be out {ARO).
The limits on contained water volume and boron concentration also ensure a pH value of between 7.0 and 10.0 for the solution recirculated within containment after a LOCA.
This pH band minimizes the evolution of iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.
The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics.
SALEM - UNIT 1 B 3/4 5-3 April 29, 1998 Revised by NRC letter dated
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3/4.9 REFUELING OPERATIONS BASES
==================================================================
3/4.9.1 BORON CONCENTRATION The limitations on minimum boron concentration (2000 ppm) ensure that:. 1) the reactor will remain subcri tical during. CORE ALTERATIONS, *and 2) a uniform boron concentration is maintained for reactivity control in the water volume having direct access to the reactor vessel. The limitation on Kett of no greater than 0.95 which includes a conservative allowance for uncertainties, is sufficient to prevent reactor criticality during refueling operations.
The sampling and analysis required by.surveillance requirement 4.9.1.2 ensures the boron concentration required by Limiting Condition of Operation 3.9.1 is met.
Sampling and analysis of the refueling canal is required if water exists in the refueling canal, regardless of the amount.
3/4.9.2 INSTRUMENTATION The OPERABILITY of the source range neutron flux monitors ensures that-redundant monitoring capability is available to detect changes in the reactivity condition of the core.
3/4.9.3 DECAY TIME The minimum requirem~nt for reactor subcriticality prior to movement of irradiated fuel assemblies in the reactor pressure vessel ensures that sufficient time has elapsed to allow the radioactive decay of the short lived fission products. This decay time is consistent with the assumptions used in the accident analyses.
3/4.9.4 CONTAINMENT BUILDING PENETRATIONS The requirements on containment building penetration closure and OPERABILITY ensure that a release of radioactive material within containment will be restricted from leakage to the environment. The OPERABILITY and closure restrictions are sufficient to restrict radioactive material release from a fuel element rupture based upon the lack of containment pressurization potential while in the REFUELING MODE.
3/4.9.5 COMMUNICATIONS The requirement for communications capability ensures that refueling station personnel can be promptly informed of significant changes in the facility status or core reactivity conditions during CORE ALTERATIONS.
SALEM - UNIT 1 B 3/4 9-1 April 29, 1998 Revised by NRC letter dated
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REACTIVITY, CONTROL SYSTEMS BASES The boron capability required below 200°F is sufficient to provide a SHUTDOWN MARGIN of 1% delta k/k after xenon decay and cooldown from 200°F to 140°F.
This condition requires either 2,600 gallons of 6,560 ppm borated water from the boric acid storage tanks or 7,100 gallons of 2,300 ppm borated water from the refueling water storage tank.
The 37,000 gallons limit in the refueling water storage tank for Modes 5 and 6 is based upon 21,210 gallons that is undetectable due to lower tap location, 8,550 gallons for instrument error, 7,100 gallons required for shutdown margin, and an additional 140 gallons due to rounding up.
The limits on contained water volume and boron concentration of the RWST also ensure a pH value of between 7.0 and 10.0 for the solution recirculated within containment after a LOCA.
This pH band minimizes the evolution of iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.
The contained water volume limits include allowance for water not available because of discharge line location and other physical characteristics.
The OPERABILITY of one boron injection system during REFUELING ensures that this system is available for reactivity control while in MODE 6.
3/4.1.3 MOVABLE CONTROL ASSEMBLIES The specifications of this section ensure that (1) acceptable power distribution limits are maintained, (2) the minimum SHUTDOWN MARGIN is maintained, and (3) limit the potential effects of rod mis-alignment on associated accident analyses.
OPERABILITY of the control rod position indicators is required to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits. OPERABLE condition for the analog rod position indicators is defined as being capable of indicating rod position to within the allowed rod misalignment relative to the bank demand position f6r a range of positions. For the Shutdown Banks, and Control Bank A this range is defined as the group demand counter indicated position between 0 and 30 steps withdrawn inclusive, and between 200 and 228 steps withdrawn inclusive.
This permits the operator to verify that the control rods in these banks are either fully withdrawn or fully inserted, the normal operating modes for these banks.
Knowledge of these banks positions in these ranges satisfies all accident analysis assumptions concerning their position.
The range for control Bank B is defined as the group demand counter indicated position between O and 30 steps withdra~ inclusive, and between.160 and 228 steps withdrawn inclusive.
For Control Banks C and D the range is defined as the group demand counter indicated position between O and 228 steps withdrawn. Comparison of the group demand counters to the bank insertion limits with verification of rod po~ition with the analog rod position indicators (after thermal soak after rod motion) is sufficient verification that the control rods are above the insertion limits.
Th~ full out position will be specifically established for each cycle by the Reload Safety Analysis for that cycle.
This position will be within the band established by "FULL WITHDRAWN" and will be administratively controlled.
This band is allowable to minimize RCCA wear, pursuant to Information Notice 87-19.
SALEM - UNIT 2 B 3/4 1-4 April 29, 1998 Revised by NRC letter dated r*,
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EMERGENCY CORE COOLING SYSTEMS BASES The LCO is not strictly a flow limit, but rather a flow limit based on a flow line resistance.
Line pressure and flow must be known to establish the proper line resistance.
Flow line resistance is-determined by assuming that the RCS pressure is at normal operating pressure, and that the centrifugal charging pump discharge pressure is greater than or equal to 2430 psig.
Charging pump header pressure is used instead of RCS pressure, since it is more representative of flow diversion during an accident.
The additional LCO modifier, charging flow control valve full open, is required since the valve is designed to fail open.
With the LCO specified discharge pressure and control valve position, a flow limit is established.
This flow limit is used in the accident analysis.
A provision has been added to exempt surveillance requirement 4.0.4 for entry into MODE 3, since the surveillance cannot be performed in a lower mode.
The exemption is permitted for up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after the RCS pressure has stabilized within +/- 20 psig of normal operating pressure.
The RCS pressure requirement produces the conditions necessary to correctly set the manual throttle valves.
The exemption is limited to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to ensure*timely surveillance completion once the necessary conditions are established.
3/4.5.5 REFUELING WATER STORAGE TANK The OPERABILITY of the RWST as a part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECCS in the event of a LOCA.
The limits on RWST minimum volume and boron concentrations ensure that:
(1) sufficient water is available within containment to permit recirculation cooling flow to the core, (2) the reactor will remain subcritical in the cold condition following a small LOCA assuming complete mixing of the RWST, RCS, and ECCS water volumes with all control rods inserted except the most reactive control assembly (ARI-1), and (3) the reactor will remain subcritical in the cold condition following a large break LOCA (break flow area > 3.0 sq. ft.)
assuming complete mixing of the RWST, RCS, and ECCS water and other sources of water that may eventually reside in the sump following a LOCA with all control rods assumed to be out (ARO).
The limits on contained water volume and boron concentration also ensure a pH value of between 7.0 and 10.0 for the solution recirculated within containment after a* LOCA.
This pH band minimizes the evolution of iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.
The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other_physical characteristics.
SALEM - UNIT 2 B 3/4 5-3 April 29, 1998 Revised by NRC letter dated
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I 3/4.9 REFUELING OPERATIONS BASES
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3/4.9.1 BORON CONCENTRATION The limitations on minimum boron concentration (2000 ppm) ensure that: 1) the reactor will remain subcritical during CORE ALTERATIONS, and 2) a uniform boron concentration is maintained for reactivity control in the water volume having direct access to the reactor vessel. The limitation on Kett of no i
greater than 0.95 which includes a conservative allowance for uncertainties, is sufficient to prevent reactor criticality during refueling operations.
The sampling and analysis required by surveillance requirement 4.9.1.2
- .ensures the boron concentration required by Limiting Condition of Operation 3.9.1 is met.
Sampling and analysis of the refueling canal is required if water exists in the refueling canal, regardless of the amount.
3/4.9.2 INSTRUMENTATION The OPERABILITY of the source range neutron flux monitors ensures that redundant monitoring capability is available to detect changes in the reactivity condition of the core.
3/4.9.3 DECAY TIME The minimum requirement for reactor subcriticality prior to movement of irradiated fuel assemblies in the reactor pressure vessel ensures that sufficient time has elapsed to allow the radioactive decay of the short lived fission products.. This decay time is consistent with the assumptions used in the accident analyses.
3/4.9.4 CONTAINMENT BUILDING PENETRATIONS The requirements on containment building penetration closure and OPERABILITY ensure that a release of radioactive material within containment will be restricted from leakage to the environment. The' OPERABILITY and ciosure restrictions are sufficient to restrict radioactive material release from a fuel element. rupture based upon the lack of containment pressurization potential while in the REFUELING MODE.
3/4.9.5 COMMuNICATIONS The requirement for communications capability ensures that refueling station personnel can be promptly informed of significant changes in the facility status or core reactivity conditions during CORE ALTERATIONS.
SALEM - UNIT 2 B 3/4 9-1 April 29, 1998 Revised by NRG letter dated