ML13064A275

LaSalle County Station, Units 1 and 2 - Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Reliable Hardened Containment Vents (Order Number EA-12-050)

ML13064A275
Person / Time
Site:	LaSalle
Issue date:	02/28/2013
From:	Kaegi G T Exelon Generation Co
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
RS-13-112
Download: ML13064A275 (28)

Text

Exelon Generation RS-13-112 February 28, 2013 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 LaSalle County Station, Units 1 and 2 Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 Order No. EA-12-050

Subject:

Overall Integrated Plan in Response to March 12, 2012 Commission Order Modifying Licenses with Regard to Requirements for Reliable Hardened Containment Vents (Order Number EA-12-050)

References:

1. NRC Order Number EA-12-050, "Issuance of Order to Modify Licenses with Regard to Reliable Hardened Containment Vents," dated March 12, 2012 2. NRC Interim Staff Guidance JLD-ISG-2012-02, "Compliance with Order EA-12-050, Reliable Hardened Containment Vents", Revision 0, dated August 29,2012 3. Exelon Generation Company, LLC's Initial Status Report in Response to March 12,2012 Commission Order Modifying Licenses with Regard to Reliable Hardened Containment Vents (Order Number EA-12-050), dated October 25,2012 On March 12, 2012, the Nuclear Regulatory Commission

("NRC" or "Commission")

issued an order (Reference

1) to Exelon Generation Company, LLC (EGC). Reference 1 was immediately effective and directs EGC to require BWRs with Mark I and Mark II containments to take certain actions to ensure the operability of reliable hardened containment vent (RHCV) systems to remove decay heat and maintain control of containment pressure following events that result in loss of active containment heat removal capability or prolonged Station Blackout (S80). Specific requirements are outlined in Attachment 2 of Reference

1. Reference 1 requires submission of an Overall Integrated Plan by February 28, 2013. The interim staff guidance (Reference

2) was issued August 29, 2012 which provides direction regarding the content of this Overall Integrated Plan. The purpose of this letter is to provide the Overall Integrated Plan pursuant to Section IV, Condition C.1 , of Reference

1. This letter confirms EGC has received Reference 2 and has an Overall Integrated Plan complying with the guidance for the purpose of ensuring the functionality of reliable hardened containment vent (RHCV) systems to remove decay heat and maintain control of containment pressure following events that result in loss of active containment heat removal capability or prolonged Station Blackout (SBO) as described in Attachment 2 of Reference

1. Reference 3 provided the EGC initial status report regarding reliable hardened containment vents, as required by Reference

1.

1.LaSalle County Station, Units 1 and 2 Hardened Containment Vent System Overall Integrated Plan

References:

Licensees shall provide a complete description of the system, including important operational characteristics. The level of detail generally considered adequate is consistent with the level of detail contained in the licensee's Final Safety Analysis Report.

System Overview:

The Hardened Containment Vent System will be designed to mitigate lossof-decay-heat removal by providing sufficient containment venting capability to limit containment pressurization. The vent will be designed with sufficient capacity to accommodate decay heat input equivalent to 1% of 4067 MWt which accounts for a 14.7% potential power uprate abovethe current licensed thermal power of 3546 MWt. Thus, the hardened vent capacity will be adequate to relieve decay heat for a prolonged station blackout (SBO) event.

intended for use as one element of core damage prevention strategies. Venting the containment to remove decay heat and limit containment pressurization supports core cooling strategies during a prolonged SBO event.

path from the containment to an elevated release point above the Reactor Building roof is shown in the simplified piping and instrumentation diagram (P&ID) in Section 8 of this report.

each unit is fully independent of the other unit The piping flow path is dedicated function; there are no inter-system connections; and no ductwork will be used in the flow path. This ensures flow out of the containment is discharged to the outside atmosphere above the unit's Reactor Building.

Equipment and components:

a)Containment isolation piping, valves and controls -

piping and supports up to and including the second containment isolation valve designed in accordance with the existing containment penetration design basis.

The design of the CIVs will be consistent with the plant's CIV design basis. The in-series CIVs are normally closed, fail closed airoperated valves existing penetrations open to the containment atmosphere, located outside the containment.

flow path downstream of the CIVs will not interface with any other fluid system. Therefore, there are no interfacing system valves.

flow path downstream of the CIVs will have a normally closed, fail-closed, air-operated Pressure will control upstream pressure and have an adjustable pressure setpoint to allow pressure control over a large range of pressures, which includes pressures well below Licensees shall provide complete description of the system, including important operational characteristics.

The level of detail generally considered adequate is consistent with the level of detail contained in the licensee's Final Safety Analysis Report.

System Overview:

Equipment and components:

containment design pressure up to pressures near containment design pressure.

operation.

System control:

System control:

The HCVS shall be designed to minimize the reliance on operator actions.

During events that significantly challenge plant operations, individual operators are more prone to human error. In addition, the plant operations staff may be required to implement strategies and/or take many concurrent actions that further places a burden on its personnel.

During the prolonged SBO condition at the Fukushima Dai-ichi units, operators faced many significant challenges while attempting to restore numerous plant systems that were necessary to cool the reactor core, including the containment venting systems. The difficulties faced by the operators related to the location of the HCVS valves, ambient temperatures and radiological conditions, loss of all alternating current electrical power, loss of motive force to open the vent valves, and exhausting do battery power. The NRC staff recognizes that operator actions will be needed tooperate the HCVS valves; however, the licensees shall consider design features for the system that will minimize the and reliance on operator actions to the extent possible during a variety of plant conditions, as further discussed in this ISG.

The HCVS shall be designed to be operated from a control panel located in the main control room or a remote but readily accessible location. The HCVS shall be designed to be fully functional and self sufficient with permanently installed equipment in the plant, without the need for portable equipment or connecting thereto, until such time that additional on-site or off-site personnel and portable equipment become available.

The HCVS shall be capable of operating in this mode (i.e., relying on permanently installed equipment) for at least 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> during the prolonged SBO, unless a shorter period is justified by the licensee. The HCVS operation in this mode depends on a variety of conditions, such the cause for theSBO (e.g., seismic event, flood, tornado, high winds), severity of the event, and time required for additional help to reach the plant, move portable equipment into place, and make connections to the HCVS.

When evaluating licensee justification for periods than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, the NRC staff will consider the number of actions and the cumulative demand on personnel resources that are needed to maintain HCVS functionality (e.g., installation of portable equipment during the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore power to the HCVScontrols and/or instrumentation) as a result of design limitations. For example, the use of supplemental portable power sources may be acceptable if the supplemental power was readily available, could be quickly and easily moved into place, and installed through the use of pre-engineered quick disconnects, and the necessary human actions were identified along with the time needed to complete those actions.

Conversely, supplemental power sources located in an unattended warehouse that require a qualified electrician to temporarily wire into the panel would not be considered acceptable by the staff because its installation requires of complex, time-consuming actions in order to achieve a successful outcome.

There are similar examples that could apply to mechanical systems, such pneumatic/compressed air systems.

The HCVS shall be designed to minimize the reliance on operator actions.

During events that significantly challenge plant operations, individual operators are more prone to human error. In addition, the plant operations staff may be required to implement strategies and/or take many concurrent actions that further places burden on personnel.

During the prolonged sao condition at the Fukushima Dai-ichi units, operators faced many significant challenges while attempting to restore numerous plant that were necessary to cool the reactor core, including the containment venting The difficulties faced by the operators related to the location of the HCVS valves, ambient temperatures and radiological conditions, of a/l alternating current electrical

power, of motive force to open the vent valves, and exhausting dc battery power. The NRC staff recognizes that operator actions will be needed to operate the HCVS valves; however, the licensees shall consider design features for the that will minimize the need and reliance on operator actions to the extent possible during variety of plant conditions, further discussed in this ISG. The HCVS shall be designed to be operated from control panel located in the main control room or remote but readily accessible location.

The HCVS shall be designed to be fully functional and sufficient with permanently installed equipment in the plant, without the need for portable equipment or connecting thereto, until such time that additional on-site or off-site personnel and portable equipment become available.

The HCVS shall be capable of operating in this mode (i.e., relying on permanently installed equipment) for at least hours during the prolonged sao, unless shorter period is justified by the licensee.

The HCVS operation in this mode depends on variety of conditions, such the cause for the sao (e.g., seismic event, flood, tornado, high winds), severity of the event, and time required for additional help to reach the plant, move portable equipment into place, and make connections to the HCVS. When evaluating licensee justification for periods than hours, the NRC will consider the number of actions and the cumulative demand on personnel resources that are needed to maintain HCVS functionality (e.g., installation of portable equipment during the first hours to restore power to the HCVS controls and/or instrumentation) result of design limitations.

For example, the use of supplemental portable power sources may be acceptable if the supplemental power readily available, could be quickly and easily moved into place, and installed through the use of pre-engineered quick disconnects, and the necessary human actions were identified along with the time needed to complete those actions. Conversely, supplemental power sources located in an unattended warehouse that require qualified electrician to temporarily wire into the panel would not be considered acceptable by the staff because its installation requires series of complex, time-consuming actions in order to achieve successful outcome. There are similar examples that could apply to mechanical such pneumatic/compressed air LaSalle County Station, Units 1 and 2 HCVS Overall Integrated Plan The HCVS shall be designed to minimize plant operators' exposure to occupational hazards, such as extreme heat stress, while operating the HCVS system.

During a prolonged SBO, the drywell, wetwell (torus), and nearby in the plant where HVCS components are expected to be located will likely experience an excursion in temperatures due to inadequate containment cooling combined with loss of normal and emergency building ventilation systems.

In addition, installed normal and emergency lighting in the plant may not be available. Licensees should take into consideration plant conditions expected to experienced during applicable beyond design basis external when locating valves, instrument air supplies, and other components that will be required to safely operate the HCVS system. Components required for manual operation should be placed in areas that are readily accessible to plant operators, and not require additional actions, such as the installation of ladders or temporary scaffolding, to operate the system.

When developing a design strategy, the NRC staff expects licensees to analyze potential plant conditionsand use its acquired knowledge of these areas, in terms of how temperatures would react to extended SBO conditions and the lighting that would be available during beyond design external events. This knowledge also provides an input to system operating procedures, training, the choice of protective clothing, required tools and equipment, and portable lighting.

The HCVS shall be designed to minimize plant operators' exposure to occupational hazards, such extreme heat stress, while operating the HCVS system.

During prolonged sao, the drywell, wetwell (torus), and nearby areas in the plant where HVCS components are expected to be located will likely experience an excursion in temperatures due to inadequate containment cooling combined with of normal and emergency building ventilation In addition, installed normal and emergency lighting in the plant may not be available.

Licensees should take into consideration plant conditions expected to be experienced during applicable beyond design basis extemal events when locating valves, instrument air supplies, and other components that will be required to safely operate the HCVS system. Components required for manual operation should be placed in areas that are readily accessible to plant operators, and not require additional actions, such the installation of ladders or temporary scaffolding, to operate the system. When developing design strategy, the NRC staff expects licensees to analyze potential plant conditions and use its acquired knowledge of these areas, in terms of how temperatures would react to extended sao conditions and the lighting that would be available during beyond design basis external events. This knowledge also provides an input to system operating procedures, training, the choice of protective clothing, required tools and equipment, and portable lighting.

The HCVS shall also be designed to minimize radiological consequences that would impede personnel actions needed for event response.

The design of the HCVS should take into consideration the radiological consequences resulting from the event that could negatively impact event response. During the Fukushima event, personnel actions to manually operate the vent valves were impeded due to the location of the valves in the torus rooms. The HCVS shall be designed to be placed in operation by operator actions at a control panel, located in the main control room or in a remote location. The system shall be deigned to function in this mode with permanently installed equipment providing electrical power (e.g., dc power batteries) and valve motive force (e.g., N2/air cylinders).

The system shall be designed to function in this mode for a minimum duration of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> with no operator actions required or credited, other than the system initiating actions at the control panel.

Durations of less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> will be considered if justified by adequate supporting information from the licensee. To ensure continued operation of the HCVS beyond 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, licensees may credit manual

actions, moving portable equipment to supplement electrical power and valve motive power sources.In response to Generic Letter (GL) 89-16, a number of facilities with Mark I containments installed vent valves in the torus room, the drywell, or both. Licensees can continue to use these venting locations or select new locations, provided the requirements of this guidance document are satisfied. The HCVS improves the chances of core cooling by removing heat from containment and lowering containment pressure, when core cooling is provided by other systems. If core cooling were to fail and result in the onset core damage, closure of the vent valves may become necessary if the system was not designed for accident service. In addition, leakage from the HCVS within the plant and the location of the external release from the HCVS could impact the event response from on-site operators and off-site help arriving at the plant.

An adequate strategy to minimize radiological consequences that could impede personnel actions should include the following:

The HCVS shall also be designed to minimize radiological consequences that would impede personnel actions needed for event response.

The design of the HCVS should take into consideration the radiological consequences resulting from the event that could negatively impact event response.

During the Fukushima event, personnel actions to manually operate the vent valves were impeded due to the location of the valves in the torus rooms. The HCVS shall be designed to be placed in operation by operator actions at control panel, located in the main control room or in remote location.

The system shall be deigned to function in this mode with permanently installed equipment providing electrical power (e.g., dc power batteries) and valve motive force (e.g., N2Iair cylinders).

The system shall be designed to function in this mode for minimum duration of hours with no operator actions required or credited, other than the system initiating actions at the control panel. Durations of less than hours will be considered if justified by adequate supporting information from the licensee.

To ensure continued operation of the HCVS beyond hours, licensees may credit manual actions, such moving portable equipment to supplement electrical power and valve motive power sources. In response to Generic Letter (GL) number of facilities with Mark I containments installed vent valves in the torus room, near the drywell, or both. Licensees can continue to use these venting locations or select new locations, provided the requirements of this guidance document are satisfied.

The HCVS improves the chances of core cooling by removing heat from containment and lowering containment pressure, when core cooling is provided by other systems. If core cooling were to fail and result in the onset core damage, closure of the vent valves may become necessary if the system was not designed for severe accident service. In addition, leakage from the HCVS within the plant and the location of the external release from the HCVS could impact the event response from on-site operators and off-site help arriving at the plant. An adequate strategy to minimize radiological consequences that could impede personnel actions should include the following:

1.Licensees shall provide permanent radiation shielding where necessary to facilitate personnel to valves and allow manual operation of the valves locally. Licensee may use alternatives such providing features to facilitate manual operation of valves from remote locations, as discussed further in this guidance under Requirement 1.2.2, or relocate the vent valves to areas that are significantly less challenging to operator access/actions.

2.In accordance with Requirement 1.2.8, the HCVS shall be designed for pressures that are consistent with the higher of the primary containment design pressure and the primary containment pressure limit (PCPL), as well including dynamic loading resulting from system actuation. In addition, the system shall be leak-tight. As such, ventilation duct work (i.e., sheet metal) shall not be utilized in the design of the HCVS.

Licensees should perform appropriate testing, such as hydrostatic or pneumatic testing, to establish the leak-tightness of the HCVS.

3.The HCVS release to outside atmosphere shall be at an elevation higher than adjacent plant structures.

Release through existing plant stacks is considered acceptable, provided the guidance under Requirement 1.2.6 is satisfied. If the from HCVS is through a vent stack different than the plant stack, the elevation of the stack should be higher than the nearest building or structure.

The HCVS shall have the capacity to vent the steam/energy equivalent of 1 percent of licensed/rated thermal power (unless a lower value is justified by and be able to maintain containment pressure below the primary containment design

1. Licensees shall provide permanent radiation shielding where necessary to facilitate personnel access to valves and allow manual operation of the valves locally. Licensee may use alternatives such as providing features to facilitate manual operation of valves from remote locations, as discussed further in this guidance under Requirement or relocate the vent valves to areas that are significantly less challenging to operator access/actions.

2. In accordance with Requirement the HCVS shall be designed for pressures that are consistent with the higher of the primary containment design pressure and the primary containment pressure limit (PCPL), as well as including dynamic loading resulting from system actuation.

In addition, the system shall be tight. As such, ventilation duct work (i.e., sheet metal) shall not be utilized in the design of the HCVS. Licensees should perform appropriate testing, such as hydrostatic or pneumatic testing, to establish the leak-tightness of the HCVS. 3. The HCVS release to outside atmosphere shall be at an elevation higher than adjacent plant structures.

Release through existing plant stacks is considered acceptable, provided the guidance under Requirement 1.2.6 is satisfied.

If the release from HCVS is through a vent stack different than the plant stack, the elevation of the stack should be higher than the nearest building or structure.

The HCVS shall have the capacity to vent the steam/energy equivalent of percent of licensed/rated thermal power (unless a lower value is justified by analyses), and be able to maintain containment pressure below the primary containment design pressure.

LaSalle County Station, Units 1 and 2 Integrated Plan Beyond design external events such as a prolonged SBO could result in the loss of active containment heat removal capability.

The primary design objective of the HCVS is to provide sufficient venting capacity to prevent a long

-term overpressure failure of the containment by keeping the containment pressure below the primary containment design pressure and the PCPL. The PCPL may be dictated by other factors, such as the maximum containment pressure at which the safety relief valves and the HCVS valves can be opened and closed.The NRC staff has determined that, for a vent sized under conditions of constant heat input at a rate equal to 1 percent of rated thermal power and containment pressure equal to the lower of the primary containment design pressure and the PCPL, the exhaust-flow through the vent would be sufficient to prevent the containment pressure from increasing. This determination is based on studies that have shown that the torus suppression capacity is typically sufficient to absorb the decay heat generated during at least the first three hours following the shutdown of the reactor with suppression pool as the source of injection, that decay heat is typically less than 1 percent of rated thermal power three hours following shutdown of the reactor, and that decay heat continues to decrease to well under 1 percent, thereafter. Licensees shall have an auditable engineering for the decay heat absorbing capacity of their suppression pools, selection of venting pressure such that the HCVS will have sufficient venting capacity under such conditions to maintain containment pressure at or below the primary containment design pressure and the PCPL. If required, venting capacity shall be increased to an appropriate level commensurate with the licensee's venting strategy. Licensees may also venting capacity sized under conditions of constant heat input at a rate lower than 1 percent of thermal power if it can be justified by analysis that primary containment design pressure and the PCPL would not be exceeded. In where plants were granted, have applied, or plan to apply for power uprates, the licensees shall use 1 percent thermal power corresponding to the uprated thermal power.

The for the venting capacity shall give appropriate consideration of where venting is being performed from (i.e., wetwell or drywell) and the difference in pressure between the drywell and the suppression chamber. Vent sizing for multi-unit sites must take into consideration simultaneous venting from all the units, and ensure that venting on one unit does not negatively impact the ability to vent on the other units.

capacity of the wetwell path will be designed for venting steamenergy at a capacity of 1of 4067 MWt power at containment pressure of 45 psig. This pressure is thelower of the containment design pressure (45 psig) and the PCPL value (60 psig). The thermalpower of 4067 MWt assumes a power uprate of 14.7% above the currently licensed thermal power of 3546 MWt.

be accessible to plant operators and be capable of remote operation and control, or manual operation, during sustained operations.

The preferred location for remote operation and control of the HCVS is from the main control room. However, alternate locations to the control room are also acceptable, provided the licensees take into consideration the following:

1.Sustained operations mean the ability to open/close the valves multiple times during the event.

Licensees shall determine the number of open/close cycles during the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of operation and provide supporting consistent with the plant-specific containment venting strategy.

2.An assessment of temperature and radiological conditions that operating personnel may encounter both in transit and locally at the controls. Licensee may use alternatives such providing features to facilitate manual operation of valves from remote locations or relocating/reorienting the valves.

Beyond design basis external events such prolonged SBO could result in the loss of active containment heat removal capability.

The primary design objective of the HCVS is to provide sufficient venting capacity to prevent long-term overpressure failure of the containment by keeping the containment pressure below the primary containment design pressure and the PCPL. The PCPL may be dictated by other factors, such the maximum containment pressure at which the safety relief valves (SRVs) and the HCVS valves can be opened and closed. The NRC staff has determined that, for vent sized under conditions of constant heat input at rate equal to percent of rated thermal power and containment pressure equal to the lower of the primary containment design pressure and the PCPL, the exhaust-flow through the vent would be sufficient to prevent the containment pressure from increasing.

This determination is based on studies that have shown that the torus suppression capacity is typically sufficient to absorb the decay heat generated during at least the first three hours following the shutdown of the reactor with suppression pool the source of injection, that decay heat is typically less than percent of rated thermal power three hours following shutdown of the reactor, and that decay heat continues to decrease to well under percent, thereafter.

Licensees shall have an auditable engineering basis for the decay heat absorbing capacity of their suppression pools, selection of venting pressure such that the HCVS will have sufficient venting capacity under such conditions to maintain containment pressure at below the primary containment design pressure and the PCPL. If required, venting capacity shall be increased to an appropriate level commensurate with the licensee's venting strategy.

Licensees may also use venting capacity sized under conditions of constant heat input at rate lower than percent of thermal power if it can be justified by analysis that primary containment design pressure and the PCPL would not be exceeded.

In cases where plants were granted, have applied, plan to apply for power uprates, the licensees shall use percent thermal power corresponding to the uprated thermal power. The basis for the venting capacity shall give appropriate consideration of where venting is being performed from (i.e., wetwell drywell) and the difference in pressure between the drywell and the suppression chamber. Vent sizing for multi-unit sites must take into consideration simultaneous venting from all the units, and ensure that venting on one unit does not negatively impact the ability to vent on the other units.

The HCVS shall be accessible to plant operators and be capable of remote operation and control, manual operation, during sustained operations.

The preferred location for remote operation and control of the HCVS is from the main control room. However, alternate locations to the control room are also acceptable, provided the licensees take into consideration the following:

1. Sustained operations mean the ability to open/close the valves multiple times during the event. Licensees shall determine the number of open/close cycles necessary during the first hours of operation and provide supporting basis consistent with the plant-specific containment venting strategy.

2. An assessment of temperature and radiological conditions that operating personnel may encounter both in transit and locally at the controls.

Licensee may use alternatives such providing features to facilitate manual operation of valves from remote locations relocatinglreorienting the valves.

3.

HCVS operation during a prolonged SBO (electric power, N2/air) shall be located above the maximum design external flood level or protected from the design basis external flood.

4.

demonstrated during the Fukushima event, the valves lost motive force including electric power and pneumatic air supply to the valve operators, and control power to solenoid valves. If direct access and local operation of the valves is not feasible due to temperature or radiological hazards, licensees should include design features to facilitate remote manual operation of the HCVS valves by means such as reachrods, chain links, hand wheels, and portable equipment to provide motive force (e.g., air/N2 bottles, diesel powered compressors, and dc batteries). The connections between the valves and portable equipment should be designed for quick deployment. If a portable motive force (e.g., air or N2 bottles, dc power supplies) is used in the design strategy, licensees shall provide reasonable protection of that equipment consistent with the staff's guidance delineated in AD-ISG-2012-01 for Order EA-12-049.

5.

scaffolding to the HCVS valves or remote operating locations.

4.Sustainability of remote operation will be addressed by locating the DC power and pneumatic motive sources at an accessible location.

only electrically active component that may be located in an inaccessible area and is required to open an will either be located in an accessible location or alternatively for each AOV will be arranged such that energizing the dedicated DC power supply can open the valve.

will be provided with a hydraulic over-ride at an accessible location in case the air operated controls fail.

Any supplemental connections will be preengineered to minimize staffing resources and any needed portable equipment will be reasonably protected from assumed hazards.

The HCVS shall include a means to prevent inadvertent actuation.

3. All permanently installed HGVS equipment, including any connections required to supplement the HGVS operation during a prolonged sao (electric power, N2/air) shall be located above the maximum design basis external flood level or protected from the design basis external flood. 4. During a prolonged sao, manual operation/action may become necessary to operate the HGVS. As demonstrated during the Fukushima event, the valves lost motive force including electric power and pneumatic air supply to the valve operators, and control power to solenoid valves. If direct access and local operation of the valves is not feasible due to temperature or radiological hazards, licensees should include design features to facilitate remote manual operation of the HGVS valves by means such as reach rods, chain links, hand wheels, and portable equipment to provide motive force (e.g., air/N2 botties, diesel powered compressors, and dc batteries).

The connections between the valves and portable equipment should be designed for quick deployment.

If a portable motive force (e.g., air or N2 botties, dc power supplies) is used in the design strategy, licensees shall provide reasonable protection of that equipment consistent with the staff's guidance delineated in JLD-ISG-2012-01 for Order EA-12-049.

5. The design shall preclude the need for operators to move temporary ladders or operate from atop scaffolding to access the HGVS valves or remote operating locations.

The HGVS shall include a means to prevent inadvertent actuation.

LaSalle County Station, Units 1 and 2 HCVS Overall Integrated Plan The design of the HCVS shall incorporate features, such as control panel key-locked switches, locking systems, rupture discs, or administrative controls to prevent the inadvertent use of the vent valves. The system shall be designed to preclude inadvertent actuation of the HCVS due to any single active failure. The design should consider general guidelines such single point vulnerability and spurious operations of any plant installed equipment associated with HCVS.

The objective of the HCVS is to provide sufficient venting of containment and prevent long-term overpressure failure of containment following the loss of active containment heat removal capability or prolonged SBO. However, inadvertent actuation of HCVS due to a design error, equipment malfunction, or operator error during a design basis loss-of-coolant accident (DBLOCA) could have an undesirable effect on the containment accident pressure (CAP) to provide adequate net positive suction to the emergencycore cooling system (ECCS) pumps. Therefore, prevention of inadvertent actuation, while important for all plants, is essential for plants relying on CAP. The licensee submittals on HCVS shall specifically include details on how this issue will be addressed on their individual plants for all situations when CAP credit is required.

The HCVS shall include a means to monitor the status of the vent system (e.g., valve position indication) from the control room or other location(s). The monitoring system shall be designed for sustained operation during a prolonged SBO.

Plant operators must be able to readily monitor the status of the HCVS at all times, including being able to understand whether or not containment pressure/energy is being vented through the HCVS, and whether or not containment integrity has been restored following venting operations. Licensees shall provide a means to allow plant operators to readily determine, or have knowledge of, the following system parameters:

(1)HCVS vent valves' position (open or closed), (2)system pressure, and (3)effluent temperature.

Other important information includes the status of supporting systems, such as availability of electrical power and pneumatic supply pressure. Monitoring by means of permanently installed gauges that are at, or nearby, the HCVS control panel is acceptable. The staff will consider alternative approaches for system status instrumentation; however, licensees must provide sufficient information and justification for alternative approaches.

The means to monitor system status shall support sustained operations during a prolonged SBO, and be designed to operate under potentially harsh environmental conditions that would be expected following a of containment heat removal capability and SBO. Power supplies to all instruments, controls, and indications shall be from the power sources supporting the HCVS operation. "Sustained operations" may include the use of portable equipment to provide an alternate source of power to components used to monitor HCVS status. Licensees shall demonstrate instrument reliability via an appropriate combination of design, analyses, operating experience, and/or testing of channel components for the following sets of parameters:

The design of the HGVS shall incorporate features, such control panel key-locked switches, locking systems, rupture discs, or administrative controls to prevent the inadvertent use of the vent valves. The system shall be designed to preclude inadvertent actuation of the HGVS due to any single active failure. The design should consider general guidelines such single point vulnerability and spurious operations of any plant installed equipment associated with HGVS. The objective of the HGVS is to provide sufficient venting of containment and prevent long-term overpressure failure of containment following the loss of active containment heat removal capability or prolonged sao. However, inadvertent actuation of HGVS due to design error, equipment malfunction, or operator error during design basis loss-of-coolant accident (DaLOGA) could have an undesirable effect on the containment accident pressure (GAP) to provide adequate net positive suction head to the emergency core cooling system (EGGS) pumps. Therefore, prevention of inadvertent actuation, while important for all plants, is essential for plants relying on GAP. The licensee submittals on HGVS shall specifically include details on how this issue will be addressed on their individual plants for all situations when GAP credit is required.

The HGVS shall include means to monitor the status of the vent system (e.g., valve position indication) from the control room or other location(s).

The monitoring system shall be designed for sustained operation during prolonged saQ.

Plant operators must be able to readily monitor the status of the HGVS at all times, including being able to understand whether or not containment pressure/energy is being vented through the HGVS, and whether or not containment integrity has been restored following venting operations.

Licensees shall provide means to allow plant operators to readily determine, or have knowledge the following system parameters:

(1) HGVS vent valves' position (open or closed), (2) system pressure, and (3) effluent temperature.

Other important information includes the status of supporting systems, such availability of electrical power and pneumatic supply pressure.

Monitoring by means of permanently installed gauges that are at, or nearby, the HGVS control panel is acceptable.

The staff will consider alternative approaches for system status instrumentation; however, licensees must provide sufficient information and justification for alternative approaches.

The means to monitor system status shalJ support sustained operations during prolonged sao, and be designed to operate under potentially harsh environmental conditions that would be expected following of containment heat removal capability and saQ. Power supplies to all instruments, controls, and indications shall be from the power sources supporting the HGVS operation. "Sustained operations" may include the use of portable equipment to provide an alternate source of power to components used to monitor HCVS status. Licensees shall demonstrate instrument reliability via an appropriate combination of design, analyses, operating experience, and/or testing of channel components for the following sets of parameters:

radiological conditions that the instruments may encounter under normal plant conditions, and during and after a prolonged SBO event.temperatures and pressure conditions as described under requirement 1.2.8, including dynamic loading from system operation.humidity based on instrument location and effluent conditions in the HCVS.

The HCVS shall include to monitor the effluent discharge for radioactivity that may be from operation of the HCVS. The monitoring system shall provide indication in the control room or other location(s), and shall be designed for sustained operation during a prolonged SBO.

Licensees shall provide an independent to monitor overall radioactivity that may be released from the HCVS discharge. The radiation monitor does not need to meet the requirements of NUREG 0737 for monitored releases, nor does it need to be able monitor releases quantitatively to ensure compliance with Title 10 of the Code of Federal Regulations (10 CFR) Part 100 or 10 CFR Section 50.67. A wide-range monitoring system to monitor the overall activity in the release providing indication that effluent from the

containment environment that is passing by the monitor is acceptable. The use of other existing radiation monitoring capability in lieu of an independent HCVS radiation monitor is not acceptable because plant operators need accurate information about releases coming from the containment via the HCVS in order to make informed decisions on operation of the reliable hardened venting system.The monitoring system shall provide indication in the control room or a remote location (i.e., HCVS control panel) for the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of an extended SBO with electric power provided by permanent DC battery sources, and supplemented by portable power sources for sustained operations. Monitoring radiation levels is required only during the events that necessitate operation of the HCVS. The reliability of the effluent monitoring system under the applicable environmental conditions shall be demonstrated by methods described under Requirement 1.2.4.

• radiological conditions that the instruments may encounter under normal plant conditions, and during and after a prolonged sao event.

• temperatures and pressure conditions as described under requirement including dynamic loading from system operation.

• humidity based on instrument location and effluent conditions in the HCVS.

The HCVS shall include a means to monitor the effluent discharge for radioactivity that may be released from operation of the HCVS. The monitoring system shall provide indication in the control room or other location(s), and shall be designed for sustained operation during a prolonged SaD.

Licensees shall provide an independent means to monitor overall radioactivity that may be released from the HCVS discharge.

The radiation monitor does not need to meet the requirements of NUREG 0737 for monitored releases, nor does it need to be able monitor releases quantitatively to ensure compliance with Title 10 of the Code of Federal Regulations (10 CFR) Part 100 or 10 CFR Section 50.67. A wide-range monitoring system to monitor the overall activity in the release providing indication that effluent from the containment environment that is passing by the monitor is acceptable.

The use of other existing radiation monitoring capability in lieu of an independent HCVS radiation monitor is not acceptable because plant operators need accurate information about releases coming from the containment via the HCVS in order to make informed decisions on operation of the reliable hardened venting system. The monitoring system shall provide indication in the control room or a remote location (i.e., HCVS control panel) for the first hours of an extended sao with electric power provided by permanent DC battery sources, and supplemented by portable power sources for sustained operations.

Monitoring radiation levels is required only during the events that necessitate operation of the HCVS. The reliability of the effluent monitoring system under the applicable environmental conditions shall be demonstrated by methods described under Requirement 1.2.4.

The HCVS shall include design features to minimize unintended cross flow of vented fluids within a unit and between units on the site.

At Fukushima, an explosion occurred in Unit 4, which was in a maintenance outage at the time of the event.

Although the facts have not been fully established, a likely cause of the explosion in Unit 4 is that hydrogen leaked from Unit 3 to Unit 4 through a common venting system. System cross-connections present a potential for steam, hydrogen, and airborne radioactivity leakage to other areas of the plant and to adjacent units at multi-unit sites if the units are equipped with common vent piping. In this context, a design that is

free of physical and control interfaces with other systems eliminates the potential for any cross-flow and is one way to satisfy this requirement. Regardless, system design shall provide design features to prevent the cross flow of vented fluids and migration to other within the plant or to adjacent units at multi-unit sites.

The current design of the hardened vent at several plants in the U.S. includes cross connections with the standby gas treatment system, which contains sheet metal ducts and filter and fan housings that are not leak tight hard pipes. In addition, dual unit plant sites are often equipped with a common plant stack.

Examples of acceptable means for prevention of cross flow is by valves, leak-tight dampers, and check valves, which shall be designed to automatically close upon the initiation of the HCVS and shall remain closed for long the HCVS is in operation. Licensee's shall evaluate the environmental conditions (e.g.

pressure, temperature) at the damper locations during venting operations to ensure that the dampers will remain functional and sufficiently leak-tight, and if necessary, replace the dampers with other suitableequipment such valves. If power is required for the interfacing valves to move to isolation position, it shall be from the same power sources the vent valves. Leak tightness of any such barriers shall be periodically verified by testing as described under Requirement 1.2.7.

both units are fully independent of each other with separate discharge points.

Therefore, the capacity at each unit is independent of the status of the other unit each unit has no interfacing systems. This eliminates any potential for inter-system leakage through valves and dampers, and it eliminates the need to isolate interfacing system valves.

The HCVS shall include features and provision for the operation, testing, inspection and maintenance adequate to ensure that reliable function and capability are maintained.

The HCVS piping run shall be designed to eliminate the potential for condensation accumulation, subsequent water hammer could complicate system operation during intermittent venting or to withstand the potential for water hammer without compromising the functionality of the system. Licensees shall provide a drain valves, pressure and temperature gauge connections) to periodically test system components, including exercising (opening and closing) the vent valve(s). In situations where total elimination of condensation is not feasible, HCVS shall be designed to accommodate condensation, including applicable water hammer loads.

The HCVS outboard of the containment boundary shall be tested to ensure that vent flow is released to the outside with minimal leakage, if any, through the interfacing boundaries with other systems or units.

Licensees have the option of individually leak testing interfacing valves or testing the overall leakage of the HCVS volume by conventional leak rate testing methods. The test volume shall envelope the HCVS between the outer primary containment isolation barrier and the vent exiting the plant buildings, including the The HCVS shall include design features to minimize unintended cross flow of vented fluids within unit and between units on the site.

At Fukushima, an explosion occurred in Unit which was in maintenance outage at the time of the event. Although the facts have not been fully established, likely cause of the explosion in Unit is that hydrogen leaked from Unit to Unit through common venting system. System cross-connections present potential for steam, hydrogen, and airborne radioactivity leakage to other areas of the plant and to adjacent units at multi-unit sites if the units are equipped with common vent piping. In this context, design that is free of physical and control interfaces with other systems eliminates the potential for any cross-flow and is one way to satisfy this requirement.

Regardless, system design shall provide design features to prevent the cross flow of vented fluids and migration to other areas within the plant or to adjacent units at mUlti-unit sites. The current design of the hardened vent at several plants in the U.S. includes cross connections with the standby gas treatment system, which contains sheet metal ducts and filter and fan housings that are not leak tight hard pipes. In addition, dual unit plant sites are often equipped with common plant stack. Examples of acceptable means for prevention of cross flow is by valves, leak-tight dampers, and check valves, which shall be designed to automatically close upon the initiation of the HCVS and shall remain closed for long the HCVS is in operation.

Licensee's shall evaluate the environmental conditions (e.g. pressure, temperature) at the damper locations during venting operations to ensure that the dampers will remain functional and sufficiently leak-tight, and if necessary, replace the dampers with other suitable eqUipment such valves. If power is required for the interfacing valves to move to isolation position, it shalJ be from the same power sources the vent valves. Leak tightness of any such barriers shall be periodically verified by testing described under Requirement The HCVS shall include features and provision for the operation, testing, inspection and maintenance adequate to ensure that reliable function and capability are maintained.

The HCVS piping run shall be designed to eliminate the potential for condensation accumulation, subsequent water hammer could complicate system operation during intermittent venting or to withstand the potential for water hammer without compromising the functionality of the system. Licensees shalJ provide means (e.g., drain valves, pressure and temperature gauge connections) to periodically test system components, including exercising (opening and closing) the vent valve(s).

In situations where total elimination of condensation is not feasible, HCVS shall be designed to accommodate condensation, including applicable water hammer loads. The HCVS outboard of the containment boundary shall be tested to ensure that vent flow is released to the outside with minimal leakage, if any, through the interfacing boundaries with other systems or units. Licensees have the option of individually leak testing interfacing valves or testing the overall leakage of the HCVS volume by conventional leak rate testing methods. The test volume shall envelope the HCVS between the outer primary containment isolation barrier and the vent exiting the plant buildings, including the

volume up to the interfacing valves. The test pressure shall be based on the HCVS design pressure.

Permissible leakage rates for the interfacing valves shall be within the requirements of American Society of Mechanical Engineers Operation and Maintenance of Nuclear Power Plants Code (ASME OM) - 2009, Subsection ISTC - 3630 (e) (2), or later edition of the ASME OM Code. When testing the HCVS volume, allowed leakage shall not exceed the sum of the interfacing valve leakages as determined from the ASME OM Code. The NRC staff will consider a higher leakage acceptance values if licensees provide acceptable justification.

When reviewing such requests, the NRC staff will consider the impact of the leakage on the habitability of the rooms and areas within the building and operability of equipment in these during the event response and subsequent recovery periods. Licensees shall implement the following operation, testing and inspection requirements for the HCVS to ensure reliable operation of the system.

Testing and Inspection Requirements Description Frequency Cycle the HCVS valves and the interfacing system valves not used to Once per year maintain containment integrity during operations.

Perform visual inspections and a walkdown of HCVS components Once per operating cycle Test and calibrate the HCVS radiation monitors.

Once per operating cycle Leak test the HCVS.

(1) Prior to first declaring the system functional,(2) Once every five years thereafter; and (3) After restoration of any breach of system boundary within the buildings Validate the HCVS operating procedures by conducting an open/close Once per every other test of the HCVS control logic from its control panel and ensuring that operating cycle all interfacing system valves move to their proper (intended) positions.

The HCVS shall be designed for pressures that are consistent with maximum containment design pressures, as welldynamic loading resulting from system actuation.

The vent system shall be designed for the higher of the primary containment design pressure or PCPL, and a saturation temperature corresponding to the HCVS design pressure. However, if the venting location is from the drywell, an additional margin of 50 OF shall be added to the design temperature because of the potential for superheated conditions in the drywell. The piping, valves, and the valve actuators shall be designed to withstand the dynamic loading resulting from the actuation of the system, including piping reaction loads from valve opening, concurrent hydrodynamic loads from SRV discharges to the suppression volume up to the interfacing valves. The test pressure shall be based on the HCVS design pressure.

Permissible leakage rates for the interfacing valves shall be within the requirements of American Society of Mechanical Engineers Operation and Maintenance of Nuclear Power Plants Code (ASME OM) 2009, Subsection ISTC 3630 (e) or later edition of the ASME Code. When testing the HCVS volume, allowed leakage shall not exceed the sum of the interfacing valve leakages as determined from the ASME Code. The NRC staff will consider higher leakage acceptance values if licensees provide acceptable justification.

When reviewing such requests, the NRC staff will consider the impact of the leakage on the habitability of the rooms and areas within the building and operability of equipment in these areas during the event response and subsequent recovery periods. Licensees shall implement the following operation, testing and inspection requirements for the HCVS to ensure reliable operation of the system. Testing and Inspection Requirements Description Frequency Cycle the HCVS valves and the interfacing system valves not used to Once per year maintain containment integrity during operations.

Perform visual inspections and walkdown of HCVS components Once per operating cycle Test and calibrate the HCVS radiation monitors.

Once per operating cycle Leak test the HCVS. (1) Prior to first declaring the system functional;(2)

Once every five years thereafter; and (3) After restoration of any breach of system boundary within the buildings Validate the HCVS operating procedures by conducting an open/close Once per every other test of the HCVS control logic from its control panel and ensuring that operating cycle al/ interfacing system valves move to their proper (intended) positions.

The HCVS shall be designed for pressures that are consistent with maximum containment design pressures, as well as, dynamic loading resulting from system actuation.

The vent system shall be designed for the higher of the primary containment design pressure or PCPL, and saturation temperature corresponding to the HCVS design pressure.

However, if the venting location is from the drywell, an additional margin of 50 OF shall be added to the design temperature because of the potential for superheated conditions in the drywell. The piping, valves, and the valve actuators shall be designed to withstand the dynamic loading resulting from the actuation of the system, including piping reaction loads from valve opening, concurrent hydrodynamic loads from SRV discharges to the suppression

pool, and potential for water hammer from accumulation of steam condensation during multiple venting cycles.

The HCVS shall discharge the effluent to a release point above main plant structures.

The HCVS release to outside atmosphere shall be at an elevation higher than adjacent plant structures.

Release through existing plant stacks is considered acceptable, provided the guidance under Requirement 1.2.6 is satisfied. If the release from HCVS is through a stack different than the plant stack, the elevation of the stack should be higher than the nearest building or structure. The release point should be situated away from ventilation system intake and exhaust openings, and emergency response facilities. The release stack or structure exposed to outside shall be designed or protected to withstand missiles that could be generated by the external events causing the prolonged SBO (e.g., tornadoes, high winds).

The HCVS system design shall not preclude the containment isolation valves, including the vent valve from performing their intended containment isolation function consistent with the design for the plant. These items include piping, piping supports, containment isolation valves, containment isolation valve actuators and containment isolation valve position indication components.

pool, and potential for water hammer from accumulation of steam condensation during multiple venting cycles.

The HGVS shall discharge the effluent to a release point above main plant structures.

The HGVS release to outside atmosphere shall be at an elevation higher than adjacent plant structures.

Release through eXisting plant stacks is considered acceptable, provided the guidance under Requirement 1.2.6 is satisfied.

If the release from HGVS is through a stack different than the plant stack, the elevation of the stack should be higher than the nearest building or structure.

The release point should be situated away from ventilation system intake and exhaust openings, and emergency response facilities.

The release stack or structure exposed to outside shaJl be designed or protected to withstand missiles that could be generated by the external events causing the prolonged sao (e.g., tornadoes, high winds).

The HGVS system design shall not preclude the containment isolation valves, including the vent valve from performing their intended containment isolation function consistent with the design basis for the plant. These items include piping, piping supports, containment isolation valves, containment isolation valve actuators and containment isolation valve position indication components.

The HCVS vent path up to and including the second containment isolation barrier shall be designed consistent with the design basis of the plant. These items include piping, piping supports, containment isolation valves, containment isolation valve actuators and containment isolation valve position indication components. The HCVS design, out to and including the second containment isolation barrier, shall meet safety-related requirements consistent with the design of the plant. The staff notes that in response to GL 89-16, in many the HCVS vent line connections were made to existing systems. In some the connection was made in between two existing containment isolation valves and in others to the vacuum breaker line. The HCVS system design shall not preclude the containment isolation valves, including the vent valve from performing their intended containment isolation function consistent with the design basis for the plant. The design shall include all necessary overrides of containment isolation signals and other interface system signals to enable the vent valves to open upon initiation of the HCVS from its control panel.

path piping and supports up to and including the second containment isolation valve will be designed in accordance with existing design basis. As with all other LaSalle mechanical penetrations open to the containment atmosphere (i.e., General Design Criteria 56 penetrations),

will be located outside containment. Associated actuators, position indication, and power supplies are also designed consistent with the requirements to meet the station design basis for containment isolation.

design will not preclude any existing CIVs and the new performing their intended containment isolation function when required by the plant's designbasis.

circuit for the allow operation of the valves from its control panel when required following containment pressurization and a containment isolation signal.

All other HCVS components shall be designed for reliable and rugged performance that is capable of ensuring HCVS functionality following a seismic event. These items include electrical power supply, valve actuator pneumatic supply, and instrumentation (local and remote) components.

All components of the HCVS beyond the second containment isolation barrier shall be designed to ensure HCVS functionality following the plant's design basis seismic event. These components include, in addition to the hardened vent pipe, electric power supply, pneumatic supply and instrumentation. The design of power and pneumatic supply lines between the HCVS valves and remote locations (if portable sources were to be employed) shall also be designed to ensure HCVS functionality. Licensees shall ensure that the HCVS will not impact other safety-related structures and components and that the HCVS will not be impacted by non-seismic components. The staff prefers that the HCVS components, including the piping run, be located in seismically qualified structures. However, short runs of HCVS piping in non-seismic structures are acceptable if the licensee provides adequate justification on the seismic ruggedness of these structures. The hardened vent shall be designed to conform to the requirements consistent with the applicable design codes for the plant, such the American Society of Mechanical Engineers Boiler and Pressure Vessel Code and the applicable Specifications, Codes and Standards of the American Institute of Steel Construction.

The HCVS vent path up to and including the second containment isolation barrier shall be designed consistent with the design basis of the plant. These items include piping, piping supports, containment isolation valves, containment isolation valve actuators and containment isolation valve position indication components.

The HCVS design, out to and including the second containment isolation barrier, sha/l meet safety-related requirements consistent with the design basis of the plant. The staff notes that in response to GL in many cases, the HCVS vent line connections were made to existing systems. In some cases, the connection was made in between two existing containment isolation valves and in others to the vacuum breaker line. The HCVS system design sha/l not preclude the containment isolation valves, including the vent valve from performing their intended containment isolation function consistent with the design basis for the plant. The design sha/l include al/ necessary overrides of containment isolation signals and other interface system signals to enable the vent valves to open upon initiation of the HCVS from its control panel.

A/I other HCVS components shall be designed for reliable and rugged performance that is capable of ensuring HCVS functionality fol/owing a seismic event. These items include electrical power supply, valve actuator pneumatic supply, and instrumentation (local and remote) components.

A/I components of the HCVS beyond the second containment isolation barrier shall be designed to ensure HCVS functionality following the plant's design basis seismic event. These components include, in addition to the hardened vent pipe, electric power supply, pneumatic supply and instrumentation.

The design of power and pneumatic supply lines between the HCVS valves and remote locations (if portable sources were to be employed) sha/l also be designed to ensure HCVS functionality.

Licensees shall ensure that the HCVS will not impact other safety-related structures and components and that the HCVS will not be impacted by non-seismic components.

The staff prefers that the HCVS components, including the piping run, be located in seismically qualified structures.

However, short runs of HCVS piping in non-seismic structures are acceptable if the licensee provides adequate justification on the seismic ruggedness of these structures.

The hardened vent shall be designed to conform to the requirements consistent with the applicable design codes for the plant, such as the American Society of Mechanical Engineers Boiler and Pressure Vessel Code and the applicable Specifications, Codes and Standards of the American Institute of Steel Construction.

To ensure the functionality of instruments following a seismic event, the NRC staff considers any of the following acceptable methods:Use of instruments and supporting components with known operating principles that are supplied by manufacturers with commercial quality assurance programs, such ISO9001. The procurement specifications shall include the seismic requirements and/or instrument design requirements, and specify the need for commercial design standards and testing under seismic loadings consistent with design basis values at the instrument locations.Demonstration of the seismic reliability of the instrumentation through methods that predict performance by analysis, qualification testing under simulated seismic conditions, a combination of testing and analysis, or the use of experience data. Guidance for these is based on sections 7, 8, 9, and 10 of IEEE Standard 344-2004, "IEEE Recommended Practice for Seismic Qualification of 1E Equipment for Nuclear Power Generating Stations," or a substantially similar industrial standard could be used.Demonstration that the instrumentation is substantially similar in design to instrumentation that has been previously tested to seismic loading levels in accordance with the plant design at the location where the instrument is to be installed (g-levels and frequency ranges). Such testing and analysis should be similar to that performed for the plant licensing 2.Demonstration of seismic reliability via methods that predict performance described in To ensure the functionality of instruments following a seismic event, the NRC staff considers any of the following as acceptable methods:

• Use of instruments and supporting components with known operating principles that are supplied by manufacturers with commercial quality assurance programs, such as IS09001. The procurement specifications shall include the seismic requirements and/or instrument design requirements, and specify the need for commercial design standards and testing under seismic loadings consistent with design basis values at the instrument locations.

• Demonstration of the seismic reliability of the instrumentation through methods that predict performance by analysis, qualification testing under simulated seismic conditions, a combination of testing and analysis, or the use of experience data. Guidance for these is based on sections and 10 of IEEE Standard 344-2004, "IEEE Recommended Practice for Seismic Qualification of Class E Equipment for Nuclear Power Generating Stations," or a substantially similar industrial standard could be used.

• Demonstration that the instrumentation is substantially similar in design to instrumentation that has been previously tested to seismic loading levels in accordance with the plant design basis at the location where the instrument is to be installed (g-Ievels and frequency ranges). Such testing and analysis should be similar to that performed for the plant licensing basis.

Electrical Power used for each instrument will be reported in future 6 month status reports.

Licensees shall develop, implement, and maintain procedures necessary for the safe operation of the HCVS. Procedures shall be established for system operations when normal and backup power is available, and during SBO conditions.

Procedures shall be developed describing when and how to place the HCVS in operation, the location of system components, instrumentation available, normal and backup power supplies, directions for sustained operation, including the storage location of portable equipment, training on operating the portable equipment, and testing of equipment. The procedures shall identify appropriate conditions and criteria for use of the HCVS. The procedures shall clearly state the nexus between CAP and ECCS pumps during a DBLOCA and how an inadvertent opening of the vent valve could have an adverse impact on this nexus.

The HCVS procedures shall be developed and implemented in the same manner as other plant procedures necessary to support the execution of the Emergency Operating Procedures (EOPs).

Licensees shall establish provisions for out-of-service requirements of the HCVS and compensatory measures. These provisions shall be documented in the Technical Requirements Manual (TRM) or similar document. The allowed unavailability time for the HCVS shall not exceed 30 days during modes 1, 2, and 3.

If the unavailability time exceeds 30 days, the TRM shall direct licensees to perform a assessment and take the necessary actions to restore HCVS availability in a timely manner, consistent with plant procedures and prevent future unavailability for similar causes.

and implemented following the plant's process for initiating or revising procedures and will contain the following details:appropriate conditions and criteria for use in operation,the location of system components,instrumentation available,training on operating the portable equipment, andtesting of portable equipment Licensees shall develop, implement, and maintain procedures necessary for the safe operation of the HGVS. Procedures shal/ be established for system operations when normal and backup power is available, and during SBO conditions.

Procedures sha/l be developed describing when and how to place the HGVS in operation, the location of system components, instrumentation available, normal and backup power supplies, directions for sustained operation, including the storage location of portable equipment, training on operating the portable eqUipment, and testing of equipment.

The procedures shall identify appropriate conditions and criteria for use of the HCVS. The procedures shall clearly state the nexus between GAP and EGGS pumps during a DBLOGA and how an inadvertent opening of the vent valve could have an adverse impact on this nexus. The HGVS procedures sha/l be developed and implemented in the same manner as other plant procedures necessary to support the execution of the Emergency Operating Procedures (EOPs). Licensees shal/ establish provisions for out-of-service requirements of the HGVS and compensatory measures.

These provisions sha/l be documented in the Technical Requirements Manual (TRM) or similar document.

The aI/owed unavailability time for the HGVS sha/l not exceed 30 days during modes and 3. If the unavailability time exceeds 30 days, the TRM shal/ direct licensees to perform a cause assessment and take the necessary actions to restore HGVS availability in a timely manner, consistent with plant procedures and prevent future unavailability for similar causes.

LaSalle County Station, Units 1 and 2 HCVS Overall Integrated PlanLicensee shall train appropriate personnel in the use of the HCVS. The training curriculashall include system operations when normal and backup power is available, and during SBO conditions.

All personnel expected to operate the HVCS shall receive training in of plant procedures developed for system operations when normal and backup power is available, and during SBO conditions consistent with the plants systematic approach to training. The training shall be refreshed on a periodic and as any changes occur to the HCVS.

Licensee shall train appropriate personnel in the use of the HCVS. The training curricula shall include system operations when normal and backup power is available, and during sao conditions.

All personnel expected to operate the HVCS shall receive training in the use of plant procedures developed for system operations when normal and backup power is available, and during sao conditions consistent with the plants systematic approach to training.

The training shall be refreshed on periodic basis and as any changes occur to the HCVS.

Section 7: ChangesUpdates to this Overall Integrated Implementation Plan

A piping and instrumentation diagram or a similar diagram that shows system components and interfaces with plant systems and structures is acceptable.

Relief Line WW A piping and instrumentation diagram similar diagram that shows system components and interfaces with plant systems and structures is acceptable. -------,

one-line diagram