B12476, Suppls 860930 & 1224 Requests for Extension of Single Failure Exemption.Description of Good Faith Efforts,Eccs Mods Resulting from Small & Medium LOCA Concerns & Single Failure Analysis of Core Deluge Piping Sys Encl
| ML20206A304 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 04/01/1987 |
| From: | Mroczka E CONNECTICUT YANKEE ATOMIC POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| B12476, NUDOCS 8704070483 | |
| Download: ML20206A304 (34) | |
Text
_ _ _ _ ____ _ . . _ _
1 CONNECTICUT YANKEE ATOMIC POWER COMPANY l l
B E R L I N. CONNECTICUT P o. Box 270
- HARTFoRO, CONNECTICUT 06141-0270 TELEPHONE A Pril 1,1987 203 M5-5000 1
Docket No. 50-213 B12476 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555
References:
(1) 3. F. Opeka letter to C. I. Grimes, "Haddam Neck Plant Small Break LOCA Permanent Resolution, Request for Extension of Single Failure Exemption," dated September 30,1986.
(2) C. I. Grimes letter to 3. F. Opeka, " Revision to Technical Specifications - Repositioning Flow Control Valve RH-FCV-( 796 in the Residual Heat Removal System," dated
! December 24,1986.
l 1
(3) F. M. Akstulewicz letter to CYAPCO, " Meeting Summary Concerning the Licensee's Proposed Plant Modifications for the Resolution of Recently Identified Small Break Loss-of-Coolant Accident Concerns," dated March 2,1987.
Gentlemen:
Haddam Neck Plant ECCS Modifications Additional Information - Request for Extension of Single Failure Exemption Further to References (2) and (3), Connecticut Yankee Atomic Power Company (CYAPCO) hereby submits an expanded good faith efforts description, a detailed description of the ECCS modifications as a result of the small and medium break lOCA concerns, an extensive single failure analysis and a stress analysis of the Core Deluge piping system.
In Reference (1), CYAPCO requested a one-cycle extension of the single failure exemption granted in April 1986. As previously stated, the extension is necessary because the electrical modifications for the permanent resolution cannot be completed until the 1989 refueling outage.
In December 1986, while analyzing the design for these modifications, a medium sized break in the Core Deluge System was identified which could not be sufficiently mitigated during sump recirculation. Procedures were developed, a flow control valve (FCV) was repositioned, and the technical specifications were changed to provide a temporary resolution to this problem. Reference (2) granted the technical specification change and requested that CYAPCO submit the stress analysis for the Core Deluge System. This stress analysis is provided in Attachment 3. \
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, U.S. Nuc!::ar Regulatory Commission B12476/Page 2 April 1,1937 I On Februtry 18, 1987, CYAPCO met with the Staff to discuss the ECCS l modifications. Reference (3)is a summary of this meeting. The Staff requested that CYAPCO submit a detailed description of the modification, including the justification for changing the setting of FCV-796 during the 1989 refueling 4
4 outage, a summary of LOCA analysis data, the seismic criteria for the i modification, the manual operator action times involved during switchover from injection to recirculation, the pre-operational flow testing plans, and the justifications for providing neither additional flow instrumentation nor an automatic switchover scheme. This information is provided in Attachment 1.
The Staff also requested that CYAPCO provide an in-depth ECCS single failure analysis in order to be assured that no other break locations exist that could not adequately be mitigated. This single failure analysis was completed and is i summarized in Attachment 2.
The Staff also requested that CYAPCO expand the good faiths efforts discussion j that is contaiaed in Reference (1) to include the permanent hardware modifications. This information is provided below.
Good Faith Efforts l As previously stated in Reference (1), CYAPCO seeks temporary relief from General Design Criteria (GDC) 35 through this request to extend the exemption from single failure requirements. CYAPCO requests that it be permitted to postpone full implementation to the range of breaks in question for one i
additional fuel cycle. The necessary mechanical modifications will be accomplished in the time frame in which CYAPCO previously indicated its desire i to complete the modification. However, the electrical modifications can not be completed until the 1989 refueling outage in parallel with the construction of the new switchgear room, i
CYAPCO previously described its good faith efforts to respond promptly to the discovery of the unaddressed range of small break LOCAs. Indeed, the Staff concluded in this regard that "CYAPCO has been expeditious in its efforts to satisfy the ECCS requirements, including the Interim Acceptance Criteria (IAC).
Further, the licensee has shown good faith in rectifying the problem and in j with the Commission's regulations as promptly as attempting practicable."g) comply j
! Reference (1) previously described the diligent effort put into identifying the i best permanent resolution. As described previously, CYAPCO has performed extensive additional analyses to evaluate several potential options to identify the best permanent response to this condition. CYAPCO believes that the permanent response ultimately decided upon provides the best practical solution
- for responding to LOCAs. When fully implemented, this option provides the i highest level of assurance that these breaks can be properly addressed. It is important to note that although one or more options might have been capable of more quickly providing an adequate response from the standpoint of simply I
i (1) Frank 3. Miraglia letter to 3. F. Opeka, " Exemption from Single Failure Criterion (GDC 35)- fladdam Neck Plant," dated April 28, 1986.
1 I
U.S. Nuclear Regulatory Commission B12476/Page 3 April 1,1987 satisfying the limitations of applicable requirements,(2) the solution decided upon provides the best overall reduction in risk in the most practical manner.
Thus, although full implementation will require extending the exemption for an additional fuel cycle, both from a regulatory and public health and safety standpoint, the overall benefits from the proposed permanent modification are greater than any of the other practical options considered.
Further, good cause exists for the length of the requested extension. CYAPCO will implement all necessary mechanical modifications during the Cycle 14 refueling outage. These modifications inclucje testing of new valves, piping and pipe supports.13) installation Since and mechanical this modification will not be used for Cycle 15 operation, the emergency operating procedures (EOPs) need not be changed. However, appropriate revisions to EOPs, including training thereto, will be accomplished prior to Cycle 16 operation. These changes to the procedures, specifically EOP ESI.3a and ESI.4a, will be exercised on the simulator prior to the implementation of the permanent modifications.
Similarly, changes to technical specifications regarding surveillance of the new unpowered valves have been initiated and will be submitted to the NRC by June 1,1987, in ample time for the start of Cycle 15. Additional changes to technical specifications regarding the electrical modifications will also be made and submitted to the NRC prior to the Cycle 15 refueling outage.
Presently, there are no unused, safety-related motor control center (MCC) compartments available at Haddam Neck from which to power up the new valves. However, with the installation of the new switchgear room, to be completed during the Cycle 15 refueling outage, additional safety-related MCC compartments will become available. Accordingly, all electrical modifications will be completed in 1989 during the Cycle 15 refueling outage.
As previously described, CYAPCO considered a temporary modification to accomplish power operation of these valves prior to the Cycle 15 outage. The (2)
For instance, the loop fill header option may not have strictly satisfied the core temperature limitations of the IAC for the case wherein one of the injection lines is completely severed. Also, for other break locations there remained some potential for core uncovery (even though maintaining accep table fuel cladding temperatures from a regulatory compliance standpoint). Consequently, 'CYAPCO did not consider this option to be desirable as a primary response mechanism even when equipment necessary to implement this option was available and installation thereof could have been completed sooner than the HPSI recirculation option.
(3)
CYAPCO has procured the necessary motor operated valves from other
' utilities. These valves, originally Intended to be used in now-cancelled facilities, were originally procured as safety grr.de and were expected to satisfy all applicable seismic and environmental requirements. The valves are acceptable and are fully seismically quallfled and with some minor modifications will be environmentally qualified.
U.S. Nuct:ar Regulatory Commission B12476/Page 4 April 1,1937 cost associated with " Jerry Rigging" a power supply from a safety related MCC during the 1987 refue'ing outage would exceed $500,000. The temporary modification would also require an exemption from the single failure criteria, as MCC 5 is the only MCC where emergency power will be available until the new switchgear room is completed. Consequently, Haddam Neck would be swapping mechanical single failure problems with electrical single failure problems for one cycle of operation. It is our view that this work should be done right the first time to preclude the potential for adverse effects from an undesirable configuration.
Interim modifications would also have an undesirable effect on operator training in that the operating procedures would only be valid for one cycle until the permanent modifications were completed. Current congestion on the main control boards would also complicate our ability to install a humanly engineered arrangement in the control room for the contemplated interim instrumentation and controls. This congestion will be alleviated in 1989 as a result of major (a total budget of $18 million has been allocated) modifications to upgrade the Nuclear Instrumentation, Radiation Monitoring and Reactor Protection Systems.
Hence, the planned modification schedule would enable us to optimize the final configuration in the control room, and would be synchronized with our Control Room Design Review efforts.
In summary, the best conceivable interim approach still would not satisfy single failure requirements, would be extremely expensive, would require additional occupational exposure to install and then remove electrical cabling, and would be -
interim in nature. Although powering the valves during the 1987 outage is not feasible, CYAPCO intends on performing all the necessary mechanical modifications during this outage. Details of these modifications are specified in Attachment 1.
As stated above, good faith efforts have been made to warrant extension of the subject exemption until the conclusion of the Cycle 15 outage.
Conclusion For the above reasons, the Staff is requested to grant this extension to the exemption from single failure requirements.
l Very truly yours, l CONNECTICUT YANKEE ATOMIC POWER COMPANY
$L ah E.'3 troczka g -
Sem/or Vice President Attachment cc: C. O. Thomas, ISAP Project Director Dr. T. E. Murley, Region 1 Administrator F. M. Akstulewicz, NRC Project Manager, Haddam Neck Plant P. D. Swetland, Resident Inspector, Haddam Neck Plant
Attachment i B12476/Page 1 Attachment 1 ECCS Modification The purpose of this modification is to provide a permanent, single-failure proof means to mitigate LOCAs. Figures 1-A through 1-E give the system line-ups for the injection and recirculation phases.
These modifications are considered to be nuclear safety related since the systems affected by this modification are used to mitigate the consequences of a design basis accident. All permanent equipment used and work performed for this modification is required to be QA Category I and seismically and environmentally qualified.
Mechanical Modifications The existing High Pressure Injection System (HPSI) pump suction will be cross-connected with the Residual Heat Removal (RHR) pump discharge. The cross-connect will establish the redundant means for recirculating coolant at high pressures by using an RHR pump, taking suction from the containment sump as a booster pump in series with a HPSI pump.
The core deluge line will be provided with a redundant MOV so that it can be isolated from the safety injection system during initiation of sump recirculation to mitigate the effects of a core deluge line break.
The following items are included in the scope of this modification.
o Replace existing HPSI pump suction manual valves (SI-V-854A, B) with motor-operated valves. This modification will prevent backflow of potentially contaminated water into the Refueling Water Storage Tank (RWST). The existing valve, SI-MOV-24, which is in series with these MOVs, will serve as a redundant isolation valve.
o Provide an 8" cross-tie connection between the RHR pump discharge and HPSI pump suction. The cross-tie will also contain two 8" MOVs (one for each HPSI pump) which are normally closed during plant operation and which will isolate this cross-tie. This line will also contain a manual maintenance valve which will be open during normal operation.
o Modify the existing redundant isolation valves in the HPSI pump miniflow line to pr3 vide remote operation from the control room. Presently, an air operated valve (AOV) provides redundancy to the two manual valves which isolate the HPSIline from the RWST and provide a means of preventing over-pressurization of an idle pump suction line. This modification is not required to satisfy the single failure criterion and has been postponed until the 1989 refueling outage in order to better optimize this system. It is our intention to insert additional MOVs in this line, however, the details of this modification have not yet been finalized.
o Install a 3" manual throttle valve in each of the four HPSI injection lines to prevent HPSI flow from exceeding RHR design flow when an RHR pump is feeding a HPSI pump. When in sump recirculation, two of the four HPSI
Attachment i B12476/Page 2 injection lines will be isolated to further limit HPSI flow. These valves will also be used to balance the flow through the four HPSIinjection paths.
o Replace the existing core deluge manual valve SI-V-873 with an MOV to provide a redundant, remote means to isolate core deluge from safety injection for mitigation of the effects of a core deluge line break. This valve is not required for operation until the new modification is fully implemented.
At that time, FCV-796 will be fully opened, thereby changing the flow distribution such that 3he present method for mitigating a medium break in the core deluge systemt!) will no longer be used.
All mechanical modifications, except as noted above, will be performed during the Cycle 14 refueling outage.
Electrical Modifications These modifications consist of providing safety-related electrical power and controls to provide manual operation from the control room for the HPSI suction valves, the HPSI/RHR cross-tie valves, the HPSI miniflow valves and the core deluge isolation valve. The valves on the HPSI/RHR cross-tie will be interlocked to prevent an inadvertent opening while the LPSI pump breakers are closed which could cause over-pressurization of the HPSI pump suction line. These modifications will be integrated with the new switchgear modifications to facilitate the installation of cable runs and conduits. CYAPCO intends to power two (2) of the MOVs from the safety bus in the new switchgear room and power the remaining MOVs from the old switchgear room (two (2) from a new motor control center and one (1) from MCC-5). Additional safety-related power will also be required for the new HPSI miniflow isolation valves. These modifications will be completed by the end of the Cycle 15 outage.
Flow Control Valve FCV-796 Flow control valve FCV-796 is currently throttled to ensure adequate flow to the ccre via either the charging system or the core deluge system. However, once the modification is fully implemented, FCV-796 will be fully opened.
The HPSI pump suction piping will be cross-tied to the RHR pump discharge downstream of FCV-796. Therefore, available net positive suction head (NPSH) for the HPSI pumps will be directly affected by the position of FCV-796. Since the new cross-tie will not be utilized in Cycle 15 operation, the pcMtion of FCV-796 does not have to be changed.
LOCA Analysis The Staff requested that CYAPCO submit data to provide confidence that all break sizes can be adequately mitigated. Table 1-A provides a matrix intended to show (1)
Presently, adequate core cooling can be accomp!!shed by using either the charging or core deluge systems when RCS pressure is below approximately 120 psig.
Attachment i B12476/Page 3 acceptable plant responses for the full range of LOCA break sizes. This data assumes that interruption to core flow between injection and recirculation is sufficiently brief to preclude core uncovery. A parallel effort has been completed to examine all possible break locations more extensively in order to reconfirm the ability to mitigate these breaks assuming a single failure following the ECCS long-term modifications. The results of this effort are that all break locations will meet the single failure criterion.
Seismic Criteria The seismic criteria for the Haddam Neck Plant have been evaluated under the Systernatic ISAP).t2) InEvaluation our Augustand 11,Integrated Safety) Assessment Programs (SEP and 1981 letter,( CYAPCO submitted information regarding the seismic standards used at the Haddam Neck Plant. A deadweight, thermal and dynamic seismic piping analysis is being performed for this modification. These analyses are based on the provisions of ANSI B31.1 Power Piping Code,1973 Edition, Summer 1973 Addenda. These criteria, along with the loading combinations and associated stress limits are listed in the August 11, 1981 submittal.
These criteria have been approved by the NRC,(4) and are the standard for the analyses of safety-related piping at the Haddam Neck Plant. There is no apparent advantage to building the ECCS modifications to more stringent requirements than that of the existing piping.
Procedures / Training / Operating Times The two emergency operating procedures (EOPs), ES-1.3a and El.4a, that will be affected by this modification in 1989 will be revised. CYAPCO intends to exercise the EOPs on the simulator prior to implementation. CYAPCO has determined that there will be adequate time between injection and recirculation to implement the steps in the EOPs. The basis for this conclusion is provided below. With all the valves electrically operated and controlled from the control room, CYAPCO estimates that switchover from recirculation to injection will take approximately 2.5 minutes. In 1985, the NRC conducted a walk-through to demonstrate that the manual switchover operation could be completed within the time available. An (2) Recent Correspondence: 3. F. Opeka letter to C. I. Grimes, "Haddam Neck Plant Integrated Safety Assessment Program," dated October 27,1986, and
- 3. F. Opeka letter to 3. A. Zwolinski, " Safety-Related Piping Seismic )
Qualification Program - Criteria Document," dated June 27,1985. {
(3)
W. G. Counsil letter to D. M. Crutchfield, "Haddam Neck Plant Seismic Reevaluation Program, SEP Topic III-6, Seismic Design Considerations,"
dated August 11,1981.
(4)
D. M. Crutchfield letter to W. G. Counsit, "SEP Topic III-6, Seismic Design Considerations Haddam Neck Plant," dated February 25,1983.
Attachment 1 B12476/Page 4 April 2,1985 letter (5) concluded that the 2'.5 minutes required to complete the switchover was satisfactory. CYAPCO expects our new switchover time to be very close to 2.5 minutes and therefore will also be sr.tisfactory. The actual switchover time will be verified on the simulator prior to start-up of Cycle 16.
Operational Flow Testing Upon completion of all piping modifications and non-destructive examinations, flow testing of the installed systems will be conducted to verify functionality. Each test will be run to show that the new piping will perform its intended LOCA mitigation function.
The flow testing will be performed in the following order:
- 1. HPSI injection and globe valve balancing,
- 2. Short-term recirculation verification,
- 3. Long-term recirculation verification.
The injection line balancing test will be performed with the system lined-up as shown in Figure 1-F. With one pump running, two globe valves at a time will be set to their predetermined required flow rate (1000 1 100 gpm per line). This will be repeated until each globe valve has been set by reading the flow on the temporarily installed ultrasonic flow meter. After setting the globe valves, a four loop injection test will be performed using one HPSI pump. This test will show that adequate flow to cool the core exists and that the injection lines are properly balanced.
The short-term recirculation test will be performed with the system aligned as shown in Figure 1-G. One RHR pump taking suction from Loop I will be feeding its corresponding HPSI pump on the ECCS train. The RHR heat exchanger outlet flow control valve (RH-FCV-795) will be fully open. The purpose of this test is to show that adequate NPSM exists for the HPSI and RHR pumps and that the RHR pump flow is 200G 1 200 gpm. Flow will be read using a temporary ultrasonic flow meter on the cross-tie line or another appropriate straight piping run. This line-up will ensure adequate water is being recirculated back to the RCS and that no pump damage is taking place.
The long-term recirculation test will be performed with the ECCS aligned as shown on Figure 1-H. Af ter the fuel has been returned to the reactor and the head has been reassembled, total RHR pump output will be recorded with one charging pump supplying 200 gpm to the Loop 2 cold leg and one RHR pump injecting into the reactor head through one partially open core deluge valve. The test objective is to maintain RHR flow less than 2200 gpm. This will be accomplished procedurally by requiring SI-MOV-371 A or B to be throttled, thus reducing RHR output. Flow will be read on FT-602 and by the ultrasonic flow meter. The long-term recirculation test will prove that adequate core cooling flow can be delivered to the core regardless of break size and location, i
(5) 3. A. Zwolinski letter to W. G. Counsil, " Integrated Plant Safety Assessment Report (IPSAR) Section 4.23.3, ESF Switchover From Injection to l Recirculation Mode (Time for Operator Action) - Haddam Neck Plant", dated April 2,1985.
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Attachmtnt 1 B12476/Page5 Flow Instrumentation CYAPCO does not intend to add permanent flow instrumentation to any piping in this modification. CYAPCO has concluded that additional flow instrumentation is not necessary and cannot be economically justified for the following reasons:
o Environmentally qualified flow transmitters would not be used to balance the flows in the HPSI injection lines (while setting the globe valves). Instead, this will be done with clamp-on ultrasonics. Flow transmitters cannot attain the accuracy that ultrasonics can achieve at these high flow velocities. The need for qualified flow indication for each HPSI injection line during normal or accident operation has not been demonstrated. The safety analyses and the operating procedures do not require detailed flow indication in these lines.
o Qualified flow transmitters are not required for the HPSI/RHR cross-tie piping. Flow can be adequately determined by the use of existing qualified valve position and pump motor ampere readings. However, detailed flow information is not necessary for operator action. The operator need only know if there is or is not flow, and this can be determined by the above methods.
Automatic Switchover During the February 18, 1987 meeting with the Staff, the question of whether CYAPCO had considered installing an automatic switchover from injection to i
recirculation was raised. CYAPCO does not believe an automatic switchover scheme is necessary. This issue was previously analyzed in SEP Topic VI-7.B, ESF Switchover from Injection to Recirculation mode (Automatic ECCS Realignment).
During this review, it was noted that initiation of an inadvertent switchover before sufficient water is in the sump could result in possible pump cavitation and damage. Another drawback of an automatic switchover is that it would require extensive modifications, since many new field devices would have to be installed. 1 The main issue of the SEP review was the availability of time to complete required actions. To address this concern, CYAPCO performed a walk-through of the procedure with the NRC to demonstrate that manual switchover operation could be completed within the time availqb e. Since the walk-through was completed in 2.5 minutes, the NRC concludedt3 that adequate time exists to perform the required actions. The NRC also concluded that the automatic switchover scheme is not warranted and that this issue is resolved. We believe the manual switchover operation time will not sufficiently change once the new modifications are implemented. LOCA analysis has shown that a five (5) minute switchover time yields acceptable results. For these reasons, CYAPCO believes automatic switchover is still not warranted.
Technical Specifications CYAPCO intends to submit to the NRC by June 1,1987, changes to the technical specifications regarding surveillance of the new unpowered valves. Specifically, section 3.6.B will be changed to add the five (5) new valves, two in the HPSI pump (5) Ibid I
B12476/Page 6 !
suction line, two in the HPSI/RHR cross-tie, and one in the core deluge line. The four (4) globe valves will also be included in this section and Section 4.3.G and H to require periodic surveillance.
The leak rate technical specifications will not be changed until the new modification is fully implemented. The present procedure, which will continue to be used for Cycle 15 operation, specifies that the high pressure safety injection system will be used to mitigate small breaks in the reactor coolant system. The basis contained in the Haddam Neck Plant technical specifications (Section 4.4 -
Containment Testing) states that for "such small breaks there would be no fuel damage and leakage of radioactivity from the recirculation system would be negligible." Since CYAPCO will continue to use the same procedure, this basis remains valid, and therefore, the HPSI system does not have to be included in leak rate testing. Once the ECCS modifications are installed and powered during the 1989 refueling outage, the HPSI system will be used to mitigate various break sizes. At this point in time, the HPSI system will be added to the leak rate technical specification.
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1 Attachment I B12476/Page 1 Attachment 1 ECCS Modification I The purpose of this modification is to provide a permanent, single-failure proof means to mitigate LOCAs. Figures 1-A through 1-E give the system line-ups for the injection and recirculation phases.
These modifications are considered to be nuclear safety related since the systems
! affected by this modification are used to mitigate the consequences of a design basis accident. All permanent equipment used and work performed for this
, modification is required to be QA Category I and seismically and environmentally qualified.
l Mechanical Modifications
. The existing High Pressure Injection System (HPSI) pump suction will be cross-
] connected with the Residual Heat Removal (RHR) pump discharge. The cross-2 connect will establish the redundant means for recirculating coolant at high i pressures by using an RHR pump, taking suction from the containment sump as a 1 booster pump in series with a HPSI pump.
The core deluge line will be provided with a redundant MOV so that it can be isolated from the safety injection system during initiation of sump recirculation to mitigate the effects of a core deluge line break.
- The following items are included in the scope of this modification.
o Replace existing HPSI pump suction manual valves (SI-V-854A, B) with motor-operated valves. This modification will prevent backflow of potentially contaminated water into the Refueling Water Storage Tank (RWST). The existing valve, SI-MOV-24, which is in series with these MOVs, will serve as a redundant isolation valve.
j o Provide an 8" cross-tie connection between the RHR pump discharge and
! HPSI pump suction. The cross-tie will also contain two 8" MOVs (one for each HPSI pump) which are normally closed during plant operation and which will isolate this cross-tie. This line will also contain a manual maintenance
- valve which will be open during normal operation.
- o Modify the existing redundant isolation valves in the HPSI pump miniflow line -
to provide remote operation from the control room. Presently, an - air operated valve (AOV) provides redundancy to the two manual valves which isolate the HPSIline from the RWST and provide a means of preventing over-pressurization of an idle pump suction line. This modification is not required to satisfy the single failure criterion and has been postponed until the 1989 refueling outage in order to better optimize this system. It is our intention to insert additional MOVs in this line, however, the details of this modification have not yet been finalized.
o Install a 3" manual throttle valve in each of the four HPSI injection lines to prevent HPSI flow from exceedin5 RHR design flow when an RHR pump is feeding a HPSI pump. When in sump recirculation, two of the four HPSI i
t
-. -- - . , - - . ,_ . _ ,_, , , _ _ _ _ _ - . __ - _ . , , , _ . . . ~
Attachment 1 B12476/Page 2 injection lines will be isolated to further limit HPSI flow. These valves will also be used to balance the flow through the four HPSIinjection paths.
o Replace the existing core deluge manual valve SI-V-873 with an MOV to provide a redundant, remote means to isolate core deluge from safety injection for mitigation of the effects of a core deluge line break. This valve is not required for operation until the new modification is fully implemented.
At that time, FCV-796 will be fully opened, thereby changing the flow distribution such that 3he present method for mitigating a medium break in the core deluge systemtl) will no longer be used.
All mechanical modifications, except as noted above, will be performed during the Cycle 14 refueling outage.
Electrical Modifications These modifications consist of providing safety-related electrical power and controls to provide manual operation from the control room for the HPSI suction valves, the HPSI/RHR cross-tie valves, the HPSI miniflow valves and the core deluge isolation valve. The valves on the HPSI/RHR cross-tie will be interlocked to prevent an inadvertent opening while the LPSI pump breakers are closed which could cause over-pressurization of the HPSI pump suction line. These modifications will be integrated with the new switchgear modifications to facilitate the installation of cable runs and conduits. CYAPCO intends to power two (2) of the MOVs from the safety bus in the new switchgear room and power the remaining MOVs from the old switchgear room (two (2) from a new motor control center and one (1) from MCC-5). Additional safety-related power will also be required for the new HPSI miniflow isolation valves. These modifications will be completed by the end of the Cycle 15 outage.
Flow Control Valve FCV-796 Flow control valve FCV-796 is currently throttled to ensure adequate flow to the core via either the charging system or the core deluge system. However, once the modification is fully implemented, FCV-796 will be fully opened.
The HPSI pump suction piping will be cross-tied to the RHR pump discharge downstream of FCV-796. Therefcre, available net positive suction head (NPSH) for the HPSI pumps will be directly affected by the position of FCV-796. Since the new cross-tie will not be utilized in Cycle 15 operation, the position of FCV-796 does not have to be changed.
LOCA Analysis The Staff requested that CYAPCO submit data to provide confidence that all break sizes can be adequately mitigated. Table 1-A provides a matrix intended to show (1)
Presently, adequate core cooling can be accomplished by using either the charging or core deluge systems when RCS pressure is below approximately 120 psig.
Attachment 1 B12476/Page 3 acceptable plant responses for the full range of LOCA break sizes. This data assumes that interruption to core flow between injection and recirculation is sufficiently brief to preclude core uncovery. A parallel effort has been completed to examine all possible break locations more extensively in order to reconfirm the ability to mitigate these breaks assuming a single failure following the ECCS long-term modifications. The results of this effort are that all break locations will meet the single failure criterion.
Seismic Criteria The seismic criteria for the Haddam Neck Plant have been evaluated under the Systematic Evaluation and Integrated Safety Assessment Programs (SEP and ISAP).(2) In our August 11, 1981 letter,(4 CYAPCO submitted information regarding the seismic standards used at the Haddam Neck Plant. A deadweight, thermal and dynamic seismic piping analysis is being performed for this modification. These analyses are based on the provisions of ANSI B31.1 Power Piping Code,1973 Edition, Summer 1973 Addenda. These criteria, along with the loading combinations and associated stress limits are listed in the August 11, 1981 submittal.
These criteria have been approved by the NRC,(4) and are the standard for the analyses of safety-related piping at the Haddam Neck Plant. There is no apparent advantage to building the ECCS modifications to more stringent requirements than that of the existing piping.
Procedures / Training / Operating Times The two emergency operating procedures (EOPs), ES-1.3a and El.4a, that will be affected by this modification in 1989 will be revised. CYAPCO intends to exercise the EOPs on the simulator prior to implementation. CYAPCO has determined that there will be adequate time between injection and recirculation to implement the steps in the EOPs. The basis for this conclusion is provided below. With all the valves electrically operated and controlled from the control room, CYAPCO estimates that switchover from recirculation to injection will take approximately 2.5 minutes. In 1985, the NRC conducted a walk-through to demonstrate that the manual switchover operation could be completed within the time available. An (2) Recent Correspondence: 3. F. Opeka letter to C. I. Grimes, "Haddam Neck Plant Integrated Safety Assessment Program," dated October 27,1986, and J.F. Opeka letter to 3. A. Zwolinski, " Safety-Related Piping Seismic Qualification Program - Criteria Document," dated June 27,1985.
(3) W. G. Counsil letter to D. M. Crutchfield, "Haddam Neck Plant Seismic Reevaluation Program, SEP Topic III-6, Seismic Design Considerations," j dated August 11,1981.
(4) D. M. Crutchfield letter to W. G. Counsil, "SEP Topic III-6, Seismic Design Considerations Haddam Neck Plant," dated February 25,1983.
j l
l
' Attachment 1 B12476/Page 4 April 2,1985_ letter (5) concl'uded that the 2'.5 minutes required to complete the switchover was satisfactory. CYAPCO expects our new switchover time to be very close to 2.5 minutes and therefore will also be satisfactory. The actual switchover time will be verified on the simulator prior to start-up of Cycle 16.
Operational Flow Testing
] Upon completion of all piping modifications and non-destructive examinations, flow 4
testing of the installed systems will be conducted to verify functionality. Each test will be run -to show that the new piping will perform its intended LOCA
- mitigation function.
The flow testing will be performed in the following order:
- 1. HPSIinjection and globe valve balancing,
- 2. Short-term recirculation verification,
- 3. Long-term recirculation verification.
The injection line balancing test will be performed with the system lined-up as i
shown in Figure 1-F. With one pump running, two globe valves at a time will be set j to their predetermined required flow rate (1000 1 100 gpm per line). This will be
] repeated until each globe valve has been set by reading the flow on the temporarily
- installed ultrasonic flow meter. After setting the globe valves,' a four loop
- injection test will be performed using one HPSI pump. This test will show that i adequate flow to cool the core exists and that the injection lines are properly balanced.
The short-term recirculation test will be performed with the system aligned as :
1 shown in Figure 1-G. One RHR pump taking suction from Loop I will be feeding its corresponding HPSI pump on the ECCS train. The RHR heat exchanger outlet flow i control valve (RH-FCV-796) will be fully open. The purpose of this test is to show that adequate NPSH exists for the HPSI and RHR pumps and that the RHR pump i flow is 2000 1 200 gpm. Flow will be read using a temporary ultrasonic flow meter on the cross-tie line or another appropriate straight piping run. This line-up will ensure adequate water is being recirculated back to the RCS and that no pump a damage is taking place.
The long-term recirculation test will be performed with the ECCS aligned as shown l on Figure 1-H. Af ter the fuel has been returned to the reactor and the head has
~
i
} been reassembled, total RHR pump output will be recorded with one charging pump supplying 200 gpm to the Loop 2 cold leg and one RHR pump injecting into the reactor head through one partially open core deluge valve. The test objective is to i
maintain RHR flow less than 2200 gpm. This will be accomplished procedurally by requiring SI-MOV-871 A or B to be throttled, thus reducing RHR output. Flow will be read on FT-602 and by the ultrasonic flow meter. The long-term recirculation test will prove that adequate core cooling flow can be delivered to the core i l regardless of break size and location. 1 i
(5) 3. A. Zwolinski letter to W. G. Counsil, " Integrated Plant Safety Assessment i Report (IPSAR) Section 4.23.3, ESF Switchover From Injection to i )
Recirculation Mode (Time for Operator Action) - Haddam Neck Plant", dated l April 2,1985.
j i i
-m. - - - -- - . , , = - , , -*-y-,.r-T-- -
iv-r~- --+-- 7 -- - - - - - - - y- i rw w-,--rr,-gr- -
p w wr-wr---i- ,w=-v -r --
r--g- g vie-- -- ry--yv ww
Attachment 1 B12476/Page5 Flow Instrumentation CYAPCO does not intend to add permanent flow instrumentation to any piping in this modification. CYAPCO has concluded that additional flow instrumentation is not necessary and cannot be economically justified for the following reasons:
o Environmentally qualified flow transmitters would not be used to balance the flows in the HPSI injection lines (while setting the globe valves). Instead, this will be done with clamp-on ultrasonics. Flow transmitters cannot attain the accuracy that ultrasonics can achieve at these high flow velocities. The need for qualified flow indication for each HPSI injection line during normal or accident operation has not been demonstrated. The safety analyses and the operating procedures do not require detailed flow indication in these lines.
o Qualified flow transmitters are not required for the HPSI/RHR cross-tie piping. Flow can be adequately determined Ly the use of existing qualified valve position and pump motor ampere readings. However, detailed flow information is not necessary for operator action. The operator need only know if there is or is not flow, and this can be determined by the above methods.
Automatic Switchover During the February 18, 1987 meeting with the Staff, the question of whether CYAPCO had considered installing an automatic switchover from injection to recirculation was raised. CYAPCO does not believe an automatic switchover scheme is necessary. This issue was previously analyzed in SEP Topic VI-7.B, ESF Switchover from injection to Recirculation mode (Automatic ECCS Realignment).
During this review, it was noted that initiation of an inadvertent switchover before sufficient water is in the sump could result in possible pump cavitation and damage. Another drawback of an automatic switchover is that it would require extensive modifications, since many new field devices would have to be installed.
The main issue of the SEP review was the availability of time to complete required actions. To address this coricern, CYAPCO performed a walk-through of the procedure with the NRC to cemenstrate that manual switchover operation could be completed within the time available. Since the walk-through was completed in l 2.5 minutes, the NRC concluded (51 that adequate time exists to perform the !
required actions. The NRC also concluded that the automatic switchover scheme l is not warranted and that this issue is resolved. We believe the manual switchover !
operation time will not sufficiently change once the new modifications are implemented. LOCA analysis has shown that a five (5) minute switchover time yields acceptable results. For these reasons, CYAPCO believes automatic switchover is still not warranted.
Technical Specifications 1
l CYAPCO intends to submit to the NRC by June 1,1987, changes to the technical I specifications regarding surveillance of the new unpowered valves. Specifically, l section 3.6.B will be changed to add the five (5) new valves, two in the HPSI pump (5) Ibid
Attachmsnt 1 B12476/Page 6 suction line, two in the HPSI/RHR cross-tie, and one in the core deluge line. The four (4) globe valves will also be included in this section and Section 4.3.C and H to require periodic surveillance.
The leak rate technical specifications will not be changed until the new modification is fully implemented. The present procedure, which will continue to be used for Cycle 15 operation, specifies that the high pressure safety injection system will be used to mitigate small breaks in the reactor coolant system. The basis contained in the Haddam Neck Plant technical specifications (Section 4.4 -
Containment Testing) states that for "such small breaks there would be no fuel damage and leakage of radioactivity from the recirculation system would be negligible." Since CYAPCO will continue to use the same procedure, this basis remains valid, and therefore, the HPSI system does not have to be included in leak rate testing. Once the ECCS modifications are installed and powered during the 1989 refueling outage, the HPSI system will be used to mitigate various break sizes. At this point in time, the HPSI system will be added to the leak rate technical specification.
FIGURE l-A i HADDAM NECK ECCS SYSTEM -
M NEY RWST
' i M\ 61 A
$;'insy" Fcv41:
i NEV N V-857A j
May 2 X ,\ M 1 6tB C g EV ,
S l
MOV-854 A M
- ' ' PUMPS l V-8578 M MOV-901 NEY MOV-8 B , "
Mk MOV-861D s , MOV-902 NEY LINE -
j J
F \ \ X V-102 LPSI CONTAINMENT ) y SUMP j LOOP 2 CL l EO c 9-. MOV-874 M g M "' '
FROM LOOP 1 HL ' R l F y FCV-602 2 \ MOV-871A NORM AL RHR (CLOSED) l ri
.NOV-22
\ _
RHR h MOV-873 W
E
) ;
l PUMPS (g D V-808 A H H g M
RHR HX'S MOV-33B MOV-33 A M M v-21 VCT *l E6 :@ g h
!' g M MOV-871B 1
M E MOV-373 m m -2928 B
Mov-257 h CHARGING FCV-110 y ;
wm
)
g """"S Rmm M MOV-32 FCV-110 A
FIGtfRE l-H HADDAM NECK ECCS SYSTEM ,
M RWST g NEV X
r' .
'\ NO r",61A WD i flICII IfEAn 97 NEV RECIRC USING MOV-24 d k V_857A ,
R CilARCING SvS MO - 61B NEV C
, S MOV-054 A M r HPSI ma X \ 7, MOV-901 V-8578 NEW r
r, MOV-8548 y X \ MOV-861D
) MOV-902 NEW LINE _
4 c: \ \ x V-102 LPSI PUMPS <
' CONTAINMENT g 3 )
l LOOP 2 CL
[
NMOV-874 M C
g M
FROM LOOP 1 HL F ' 2 g NORM AL RHR
'\
- y FCV'-602 g' .\
MOV-871A E (CLOSED) Mov-873
)
MOV-22 RHR h H l L2 PUMPS (g D I
V-808A H H RHR g
_ M
"'M V-21 HX'S V-33B MOV-33A M VCT H H M M ,
7'
\ U i " " v-' s H
O" I E de MOV-373! c '
MOV-257 N h[ CHARGING - FCV-110 q LOOP 2 CL REGEN HX M idOV-292C f
MOV-32 y F d FCV-110 A I
} _ _ _ _ _ _ - - - _ _ _ _ _ _
i FICilRE l-C i HADDAM NECK ECCS SYSTEM NEW RWST M 1 ri N
\ MOV-r '861 A t r.9 - b y-IIIGli llEAD RECIRC ] Moy-2 3 r "
V-857A R USING lipSI PUMPS 1987-1999 d b
%\ MO - 61B C MOV-854 A 5 r HPSI PMS lI hM0/ 61C ;
MOV-901 V-857B NEY Mov'-854B " ~
] M MOV-902 NEW LINE -
c d X X x V-102 LPSI PUMPS I
r CONTAINMENT SUMP r
d \ .
l LOOP 2 CL 874 M 0 FROM LOOP 1 R M r, ,
R NORMAL RHR _ FCV-602 Q (CLOSED) y MOV-873 MOV-871 A E lM0"V-22 RHR
} '
l ,
PUMPS (Q
V- 08 A '
~
M RHR y HX'S MOV-338 MOV-33A M [.
MOV-21 l VCT H H M M r,
\ MOV-s7:e U
G M H E MOV-3 3 g MOV-2928 MOV-257 h 6 H RG G FCV-110 y p ; )
PUMPS REGEN HX M N2a
. MOV-32 FCV-110 A
~'
FictrRE l_p flADDAM NECK ECCS SYSTEM M
NEV RWST @
N \ MO r ,- -
F t9 -
- u, 61 A 9F NEV ECCS Sil0RT TERM d ky.057A R MOV-24 RE RC LINE UP M 61B C g NEY MOV-854A HPSl ma X <\ '
OV-901 V-8578 w F NEV MOV-8548 X \ MOV-861D
) % MOV-902 NEW LINE _
0; \ \ x V-102 LPSI CONTAINMENT
} }
l LOOP 2 CL E6 c FROM LOOP l HL M g '
.MOV-874 M 0 NORM AL RHR (CLOSED) \ -
F J
pyg F v E' g
NMOV-873 .\
MOV-871 A r, R E
I M0v-22 w y ;
I ,,
euMes (g D V-808 A - H I-M Run g M V-21 HX'S MOV-33B MOV-33A M VCT F' ""-I H M M
,\ ,, U M MOV-8718 g W E 9M- M0v-373 m MOV-2928 MOV-257 @[ CHARGINO FCV-110 y ,
n M LOOP 2 CL REGEN HX Q- A MOV-32 FCV-110 A
FIGURE l-E HADDAM NECK ECCS SYSTEM NEV RWST @
ri N \ MO ri 61 A RMT_
M 9F NEV n -857A V Q ECCS LONG TERM RECIRC LINE UP MOV-24 \ '
MO - 619 C NEV M r,
NEY MOV-854 A y
MO 61C M d PUMPS V-8578 MOV-901 NEV 1
MOV-83dB N \ ri MOV-861D
) %MOV-902 NEW LINE x x x V-102 LPSI PUMPS CONTAINMENT f --,
}
c M
g ,,
- E-@ -
~
0 FROM LOOP 1 HL NORMAL RHR e _
i FCV-602 y g \ ,,
R E
(CLOSED) l MOV-22 RHR 4 MOV-873 MOV-871 A l
PUMPS
(
V-808 A H
~~
S MOV-33B MOV-33 A MOV-21 VCT ,, -4 l- n M U
,\
g MOV-871B G E
- ri X B MOV-2928 MOV-257 h CHARGING
- -110 y p ) y PUMPS LOOP 2 CL
, REGEN HX M M g MOV-292C MOV-32 d,__, A FCV-110 A
TABLE l-A LOCA MITIGATION (=ith ECCS Lang Tero Madificaticns)
I RECIRCULATION INJECTION i LT 0.005 ft2 mitigated by : Core covery is maintained by :
! SMALL i BREAK : 1 HPSI pump + SG cooling ! SG cooldown (begun,in injection l l LOCAs : ----- l phase) and 1 HPSI pump makeup flow !
No uncovery : :
- g _______...________________.._________________________________.._______________
- ! 0.005 - 0.3 ft2 mitigated by i Max boiloff is LT 1 HPSI pump flow :
! ! -------- i is bounded for retirc. by :
- 0.075 ft2 break, discharge given below) !
cold leg, RCPs off : :
- ! (Charging line break is bounded I l l l by this category)
- : Special Case: Max boiloff at 1600 sec = 58.1 lbm/sec l HPSI Injection Line break l l l l
- : PCT = 1181 F !
- : Special Cases Max boiloff at 400 sec = 88.8 lbm/sec i Core Deluge Line break : :
! 3 I ------- l 1 HPSI pump flow is GT 130.9 lbm/sec :
Bounded by 0.005 - 0.3 ft2 : !
category for injection phase :
- : Mitigated by 1 HPSI pusp : :
! : Special af f ect is recirculation ; i I : is as soon as 400 sec. :
LARGE : 0.3 - DEG of cold leg is mitigated : Max bolloff at 480 set (soonest
- LOCAs : ---------------- i 1 : PCI is limited to 2300 F (Interia 1 HPSI pump flow is 6T 130.9 lba/sec 7 :l t : Acceptance Criteria)
(1) All 4 HPSI lines are aligned to deliver HPSI flow.
(2) Two HPSI lines are aligned to deliver HPS! flow.
(3) Recirculation gpn at conservatively high bounding pressure of 1000 psig.
(4) RCS pressure is less than 700 psig.
l i SBLOCA I LONS TERM RECIRCULATION l g
l & :
I LBLOCA : Core flushing at SE B hours by RHR pump / core deluge : l l l flow and 1 Charging Pump. ! l
___._______________...________________________ ___.________ .. ._____ 1 Abbreviations: RHR - residual heat renoval l HPSI - high pressure safety injecion PCT - peak clad temperature '
LPSI - low pressure safety injection _
DE6 - double ended guillotin**
FIGURE.1-F llADDAM NECK ECCS SYSTEM
, INJECTIO:i LINE UP (Globe Valve Setting) -
l's NEV "
M
\
1 n a- sis j MD 86tA i
g, Xv-a57A
V-901 1HPSI PUMP ON q
V-9578 j & .\ ._
M(E-7b6tC ris e OM a NEW l MOV-8548l 9,g
,+ '\ HOV-0610 l _
, (th.TRA504 tc Ft.0*] MEA 59R LN6 F
d \' ,\ N DEVICE 8-oCAT8 084S V-102 l LPSI
- PUMPS CONTA9fTNT c
< S4FF g d -
- cw.rp)
- LOOP 2 Ct. -
l l@ Mc8 MAL RHR W C.
FRCHLOOPI E M )MOV-874 0
l "f lMOV-22 K - 7 FC R 2 y g
g NOV-873 g ;
- ) ; ,
RHR MOV-871 A E
! Im PUMPS 0# M H } D
~ (M)V-80sA RHR E
.T.M0v-23 HX'S Moy.333 ' Mov.33A W l vcr ,, w s g g g L
l M N0v-e71s G
- M '-4 E
MOV-373 y NOV-257 N FCV-110 NOV-2928 i
CHARGING -
d h ; )
]
,y_,,g N
""""S*
j 3 d FCV-IlOA RounHx fM0v-2,2c t00P 2 Ci. ,
_ -- _. - _m_ __
FIGURE l- G i
ilADDAM NECK ECCS SYSTEM Chort-Tern Recirculation Line-un (Testing Only) _
RWST EV C*}-- N N 061A '
r(v . [g
' ' MV
'V-857A NOV-24 d p i q Ho ; -;8688 R
Yuv
! M C
, KV g NOV-854 A M
PUMP g ri MOV 86tC 4 9,n MOV-901 V-8578 gy M NOV-8548 l g M MOV-902 MVLK
\ MOV-061D I-ULTRASartsc S J 3
C d \ \ N V-102 LPSI PUMPS CONTAMMENT f - -.
sump g
j ;c m ED)
LOOP 2 CL -
l 4'L ) %
lMOY~87*
NMAL RHR C FROM LOOP 1 E M O NORMAL RHR FC S 2 y ] \ R lMOV-22 1 RHR MOV-873 MOV-87t A E PUMP ON W l ,,
( F,80 V-808 A H Y
~
MOV-21 H S MOV-338 MOV-33 A VCT ;g
,, H H S g
M MeV-871s 6 M M y MOV-257 NOV-373 0 b '
FCV-110 NOV-2928 4
CHARGWG PUMPS OFF d }-- ; )
4 kEbfN HX MOV-292C LOOP 2 CL M
i MOV-32 N [A FCV-IIOA ,
i T ICl'F E. 1-H HADDAM NECK ECCS SYSTEM Long-Tern Pecirculation Line-up (Testing Only) -
M RWST NEV
-0< ~
---c (} NN _
f<v. yg 063A
' F NEV M MOV-24 d ' V-857A '
R
.T NEV MO -8618 {
MOV-854 A y c Ncv M g
" PUMPS OFp ri MO 6tC 9,M ,
MOV-903 V-8578 1
Nov-es48 M MOV-902 gytg DIG--\ MOV-86ID O,
l C E h \ DC v-102 LPSI PUMPS CONTAINMENT SUMP i a f----.
- ~ ,..>
LOOP 2 CL om1, j@ N$ MAL RitR
- C rean too, i g lMOV-s74 O
" " "H" IM0v-22 K _ FCMo2 y ', g K ;; a y ,pg ; 1 pHg ,y M0v-a73 MOV-e71 A E Im PUMP DN gL, M y1 _
~
v-50sA
@ H RHR P D E
VCT 9MMOV-23 HX'S V-338 MOV-33 A M L
,, H H g g
,\ U MOV-s71s 6 M --e E
HOV-257
' MOV-373 0 b ICV-110 MOV-2929 2 0 0 q p.s 1 CH ARGING ON d h g ; oPEN )
9 REGEN HX MOV-292C LOOP 2 CL MOV-3 2 d A d M FCV-Il0A ,
L _ _ - _ . -__ _ _ _ - - _ .
Attachment 2 B12476/Page1 ATTACHMENT 2 ECCS Single Failure Analysis A simplified failure modes and effects analysis (FMEA) was performed on the Haddam Neck modified ECCS pumps and valves in order to assure compliance with the single failure criteria. The tables that follow present the results of the analysis. The assumptions made in performing this FMEA are summarized below:
- 1. The analysis addressed single failure scenarios only per Standard IEEE-352.
- 2. Failure of manual valves which do not change state during the LOCA are excluded.
1
- 3. The failure of a check valve to open on the discharge of an ECCS pump is bounded by the failure of the pump and is not listed separately.
- 4. The failure of normally closed isolation valves to remain closed is addressed but only the first isolation valve to the pressure boundary is listed. Any valve in series will not be exposed to the pressure boundary unless additional failures happen.
- 5. The charging system is available for injection following the LOCA but is not required and acts as a backup to HPSI system. The charging pumps are required for long term recirculation and failure modes pertinent to alignment of charging for long term recirculation are addressed.
During the February 18,1937 meeting, the Staff requested that CYAPCO explain how RH-MOV-22 meets the single failure criteria. RH-V-303A serves as a redundant valte to RH-MOV-22. This concern was previously addressed in SEP Topic VI-7.B. At this time, the NRC questioned whether the manual valve RH-V-303A could be used as a back up to RH-MOV-22. The NRC concluded in the SER for SEP Topic VI-7.B that adequate time existed for an operator to manually open RH-V-303A as a redundant valve to RH-MOV-22.
l
._ ._. - _. . _ = .. - -. . - . _ _ - - . - . - - .-- - - .
TABLE 2-A COMPONENT FUNCTION FAILURE MODE EFFECT ON SYSTEM COMPENSATING FEATURES SI-MOV-24 RWST TO SI PUMP SPURIOUSLY CLOSES LOSS OF SUCTION TO BREAKER RACKED OUT AND SUCTION S1 PUMPS FOR POWER REMOVED TO PRECLUDE INJECTION FAILURE LPSI PUMP P-92-A INJECTION FLOW FAILS TO START / LOSS OF 1 OF 2 LPSI LPSI PUMP P-92-B AVAILABLE FAILS TO RUN PUMPS FOR INJECION LPSI PUMP P-92-B INJECTION FLOW FAILS TG START / LOSS OF 1 OF 2 LPSI LPSI PUMP P-92-A AVAILABLE FAILS TO HUN PUMPS FOR INJECION 4
CHG PUMP P-18-1A LONG TERM RECIRC. FAILS TO START / LOSS OF 1 OF 2 CHG CHG PUMP P-18-1B AVAILABLE FLOW FAILS TO RUN PUMPS FOR RECIRC. FLOW CHG PUMP P-18-1B LONG TERM RECIRC. FAILS TO START / LOSS OF 1 OF 2 CHG CHG PUMP P-18-1A AVAILABLE FLOW FAILS 10 RUN PUMPS FOR RECIRC. FLOW ,
RH-MOV-33A RHR TO CHG PUMPS FAILS TO OPEN NONE RH-MOV-338 IN PARALLEL FOR RHR TO CHG CROSSTIE i RH-MOV-338 RHR TO CHG PUMPS FAILS TO OPEN NONE RH-MOV-33A IN PARALLEL FOR RHR TO CHG CROSSTIE CH-FCV-110 THROTTLE CHG FLOW FAILS OPEN/ RHR PUMP RUNOUT THROTTLE CHG VALVES DURING LONG TERM LOSS OF AIR DURING LONG TERM CH-MOV-292B AND RECIRC. RECIRC. CH-MOV-292C l CH-FCV-110A THROTTLE CHG FLOW FAILS OPEN/ RHR PUMP RUNOUT THROTTLE CHG VALVES DURING LONG TERM LOSS OF AIR DURING LONG TERM CH-MOV-292B AND/OR RECIRC. RECIRC. CH-MOV-292C CH-MOV-2923 THROTTLE CHG FLOW FAILS AS IS RHR PUMP RUNOUT THROTTLE OPEN CORE DELUGE DURING LONG TERM DURING LONG TERM VALVE SI-871A OR D RECIRC. RECIRC.
CH-MOV-292C THROTTLE CHG FLOW FAILS AS IS RHR PUMP RUNOUT THROTTLE OPEN CORE DELUGE DURING LONG TERM DURING LONG TERM VALVE SI-871A OR 8 RECIRC. RECIRC.
LD-MOV-2OO LETDOWN ISOLATION FAILS TO CLOSE LOSS OF REACTOR LD-AOV-230 IN SERIES FOR COOLANT DUE TO ISOLATION (NEW VALVE) AND CONTINUATION OF FLOW CONTROL VALVES LETDOWN
TABLE 2-3
- COMPONENT FUNCTION FAILURE MODE EFFECT ON SYSTEM COMPENSATING FEATURES SI-MOV-901 RHR TO HPSI PUMP FAILS TO OPEN LOSS OF 1 OF 2 SI-MOV-902 TO HPSI PUMP P-15-1A FOR RECIRC. RECIRC FLOW PATHS P-15-1B IN PARALLEL FOR INITITATION RECIRC. FLOW ,
SI-MOV-902 RHR TO HPSI PUMP FAILS TO OPEN LOSS OF 1 OF 2 SI-MOV-901 TO HPSI PUMP P-15-1B FOR RECIRC. RECIRC FLOW PATHS P-15-1A IN PARALLEL FOR INITIATION RECIRC. FLOW SI-MOV-854A RWST TO HPSI PUMP FAILS TO CLOSE NONE SI-MOV-24 IN SERIES FOR P-15-1A ON RECIRC. ISOLATION;PER PROCEDURES INITIATION USE HPSI PUMP P-15-1B FOR RECIRC.
SI-MOV-854B RWST TO HPSI PUMP FAILS TO CLOSE NONE SI-MOV-24 IN SERIES FOR P-15-1B ON RECIRC. ISOLATION;PER PROCEDURES INITIATION USE HPSI PUMP P-15-1A FOR RECIRC.
SI-MOV-903 HPSI PUMPS MINIFLOW ISOLATION VALVE TO BE INSTALLED DURING 1989 REFUELING OUTAG!:
HPSI PUMP INJECTION AND RECIR FAILS TO START / LOSS OF 1 OF 2 HPSI HPSI PUMP P-15-1B P-15-1A FLOW FAIL TO RUN FLOW SOURCES AVAILABLE HPSI PUMP INJECTION AND RECIR FAILS TO START / LOSS OF 1 OF 2 HPSI HPSI PUMP P-15-1A P-15-1B FLOW FAIL TO RUN FLOW SOURCES AVAILABLE SI-MOV-861A* SI INJECTION VALVE FAILS TO OPEN FOR LOSS OF 1 OF 4 SI-MOV-861B,C,D AVAILABLE INJECTION INJECTION PATHS FOR INJECTION; FAILED VALVE CONSIDERED 1 OF 2 CLOSED FOR RECIRC. PHASE FAILS TO CLOSE NONE-REQUIRE 2 OF 4 SI-MOV-861B,C,D AVAILABLE ON RECIRC. VALVES TO CLOSE FOR ISOLATION; FAILED VALVE CONSIDERED 1 OF 2 VALVES OPEN FOR RECIRC.
O DEVELOPMENT FOR SI-MOV-B,C,D SIMILAR
TAliLE 2-C COMPONENT FUNCTION FAILURE MODE EFFECT ON SYSTEM COMPENSATING FEATURES RHR PUMP P-14-1A REC 1RC. FLOW SOURCE FAILS TO START / LOSS OF 1 OF 2 RHR RHR PUMP P-14-1B AVAILA.
FAILS TO RUN PUMPS RHR PUMP 1-14-1B RECIRC. FLOW SOURCE FAILS TO START / LOSS OF 1 OF 2 RHR RHR PUMP P-14-1A AVAIL.
FAILS TO RUN PUMPS RHR-MOV-22 SUMP TO RHR PUMPS FAILS TO OPEN NONE LINE MANUAL VALVE RH-V-808A IN PARALLEL RH-MOV-780 LOOP 1 HOT LEG TO SPURIOUSLY OPENS NONE RHR LINE RH-MOV-781 IN SERIES MAINTAINS ISOLATION RH-MOV-21 RWST TO RHR LINE SPURIOUSLY OPENS NONE RH-CV-784 IN SERIES PREVENTS BACKFLOW RH-MOV-874 RHR PUMPS TO SI SPURIOUSLY OPENS RHR PUN.' RUNOUT BREAKER OPEN, POWER PUMPS POTENTIAL REMOVED TO PREVENT FAILU.
SI-MOV-871A CORE DELUGE VALVE FAILS TO OPEN FOR LOSS OF 1 OF 2 SI-MOV-871B IN PARALLEL INJECTION PHASE INJECTION PATHS FOR INJECTION FAILS TO CLOSE NONE SI-MOV-873 IN SERIES FOR FOR SHORT TERM ISOLATION i
i RECIRC. PHASE I FAILS TO OPEN FOR LOSS OF 1 OF 2 SI-MOV-871B IN PARALLEL LONG TERM RECIRC. LONG TERM CORE FOR LONG TERM RECIRC.
PHASE l DELUGE PATHS j SI-MOV-871B CORE DELUGE VALVE FAILS TO OPEN FOR LOSS OF 1 OF 2 l SI-MOV-871A IN PARALLEL INJECTION PHASE INJECTION PATHS FOR INJECTION
, FAILS TO CLOSE NONE SI-MOV-873 IN SERIES FOR FOR SHORT TERM ISOLATION RECIRC. PHASE FAILS TO OPEN FOR LOSS OF 1 OF 2 SI-MOV-871A IN PARALLEL LONG TERM RECIRC. LONG TERM CORE FOR LONG TERM RECIRC.
PHASE DELUGE PATHS SI-MOV-873 ISOLATION VALVE SPURIOUSLY CLOSES LOSS OF 2 OF 2 CORE BREAKER RACKED OUT AND i FOR CORE DELUGE DELUGE PATHS POWER REMOVED TO PRECLUDE l FAILURE l RH-MOV-803 RHR TO LOOP 2 COLD SPURIOUSLY OPENS NONE l
LEG RH-MOV-804 IN SERIES !
MAINTAINS ISOLATION I
1 S
E ,
R 2 0 U 7 6 T 3 2 A - -
E VW VW F CO CO L L e G AF HF w N BK CK I C C e T EA EA A VB VB S L L N AS AS E VT VT P N N M KE KE O CV CV C EE EE HR HR CP CP M
E T
S Y
S N
D T
C E
F E E F N N E O O N N D
2 E
L E E E B D S S A O O OL T M L LA C . N CN E CO G R ORI OI U TIT TS L CA I SEI SI A LRT LS _
F I I I ANN AN FOI FO P
M P N U M D P U I -
P T G C H G N C H U C F ON N TO OO I TI TT T SC TC WU CU 9 RS VS T
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Attachment 3 B12476/Page1 ATTACHMENT 3 I
Core Deluge Stress Analysis -
l The NRC Staff requested that CYAPCO submit the core deluge stress analysis l
and provide information on the inspection schedule for the core deluge piping.
It is our intention to inspect one fourth of the 32 welds in this piping during the next refueling outage. The remaining welds will be inspected through the j inservice inspection (ISI) program in accordance with the schedule set forth in ASME code Section 11. We believe this plan of action is justified when 3 considering the results of the stress analysis and the consequences of high -
manrem exposures.
. In our December 17, 1986 submittal, CYAPCO incorrectly stated that t
' maximum stress was approximately 0.58 of the applicable code allowable.
Upon review of the detailed analyses of record, the maximum stress was
{ determined to be 0.83 and 0.90, respectively, of the code allowables and is summarized in Tables 3A and 3B.
The following tables summarize the maximum stresses for the various loading
- conditions considered in the Core - Deluge piping analysis. The values were obtained from the latest revisions of stress problems AC-4A and AC-4F (see '
Figure 3-A) performed as part of the on-going SEP effort at the Haddam Neck
- Plant.
1 Results of the analysis indicate that the piping stress levels for deadweight, thermal and seismic loading conditions are within their specified allowable i
limits. Thus the previous statement that the likelihood of the proposed break occurring in the core deluge line is small remains true.
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L
! (1) This estimate was originally stated in our E. 3. Mroczka letter to C. I. Grimes, dated December 17,1986, " Proposed Amendment to Facility Operating License No. DPR-61, Revision to Technical Specifications, Flow Control Valve Repositioning," and then repeated in the safety evaluation contained in the C. I. Grimes letter to 3. F. Opeka, dated December 24, 1986, " Revision to Technical Specifications - Repositioning Flow Control i Valve RH-FCV-796 in the Residual Heat Removal System." j k
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I TABLE 3-A FADDAM Mr.CK "LANT !
CORE DELUGE PIPING MAXIMUM STRESS
SUMMARY
STRESS PROBLEM AC-4A Line Nos. 6"-SI-60lR-59 & 6"-SI-250lR-39 4"-SI-250lR-41 & 4"-SI-250lR-42 Analyzed Data Maximum Code Allowable Condition Point Stress Stress
- Pressure +
~
1450 7,120 psi (1.0)S=16,600 h
psi Deadweight Thermal +
Seismic Anchor 1355 7,243 psi SA = 27,400 psi Displacements Seismic (DBE) 1375 27,071 psi (1.8) Sh=29,880 psi
+ 2PA (SRSS)+
Pressure +
Deadweight
- Based on the loading combination and stress limits defined in Table I of the Maddam Nech "lant SEP criteria docu-ment.
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TABLE 3-B
. IIADDN! HECV. "LAMT CORE DELUGE PIPING MAXIMUM STRESS
SUMMARY
STRESS PROBLEM AC-4F Line Nos. 6"-SI-60lR-38 & 6"-SI-250lR-40 4"-SI-250lR-43 & 4"-SI-250lR-44 Analyzed Data Maximum Code Allowable Condition Point Stress Stress
- Pressure + 2715 7,920 psi (1. Ch hS =16,600 psi Deadweight Thermal +
Seismic Anchor 2660 7,924 psi SA = 27,400 psi Displacements Seismic (DBE) 2765 24,724 psi (1.E) Sh=29,880 psi
+ 2PA (SRSS)+
Pressure +
Deadweight Based on the loading combination and stress limits defined in Table I of the Haddam Neck Plant SEP criteria docu-ment.
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