ML20100J094
| ML20100J094 | |
| Person / Time | |
|---|---|
| Site: | Hope Creek  |
| Issue date: | 02/26/1996 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20100J092 | List: |
| References | |
| NUDOCS 9602280236 | |
| Download: ML20100J094 (5) | |
Text
'
s@ RE% k UNITED STATES
. [.
S NUCLEAR REGULATORY COMMISSION E
f WASHINGTON, D.C. 20666-0001
\\...../
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.
94 TO FACILITY OPERATING LICENSE NO. NPF-57 PUBLIC SERVICE ELECTRIC & GAS COMPANY ATLANTIC CITY ELECTRIC COMPANY HOPE CREEK GENERATING STATION DOCKET N0. 50-354
1.0 INTRODUCTION
By letter dated February 5, 1996, as supplemented hy letter dated February 14, 1996, the Public Service Electric & Gas Company (the licensee) submitted a request for changes to the Hope Creek Generating Station (HCGS), Technical Specifications (TS). The proposed amendment would change TSs 4.6.2.2b,
" Suppression Pool Spray," and 4.6.2.3b, " Suppression Pool Cooling," to include flow through the RHR heat exchanger bypass line (in addition to the RHR heat l
exchanger) in the Suppression Pool Cooling and Suppression Pool Spray flow path used during RHR pump testing. The February 14, 1996 letter provided clarifying information that did not change the initial proposed no significant hazards consideration determination nor the Federal Reaister notice.
2.0 DISCUSSION The HCGS RHR, as described in Section 5.4.7 of the HCGS Updated Final Safety Analysis Report, consists of four independent loops which are designated as A, B, C, and D.
Each loop contains a motor-driven pump, piping, valves, instrumentation and controls.
Each loop takes suction from the suppression pool and is capable of discharging water to the reactor vessel via separate low pressure coolant injection (LPCI) nozzles, or back to the suppression pool j
via a full flow test line.
Loops A and B have heat exchangers that each contatti a bypass line, with a " butterfly" control valve, to control flow through the RHR heat exchangers. Discharge flow from the RHR and bypass line can be manually diverted to containment spray (which inciudes suppression pool spray (SPS)) or suppression pool cooling (SPC).
At the present, TS 4.6.2.2b requires that, "...each of the RHR pumps develops a flow of at least 500 gpm on recirculation flow through the RHR heat exchanger and suppression pool spray sparger when tested pursuant to Specification 4.0.5." Similarly, TS 4.6.2.3b requires that, "...each of the RHR pumps develops a flow of at least 10,000 gpm on recirculation flow f
9602280236 960226 PDR ADOCK 05000354 PDR
, through the RHR heat exchanger and the suppression' pool wher' tested pursuant to Specification 4.0.5."
The February 5, 1996 application'dould add the words "its associated closed bypass valve," after the words "RHR neat exchanger," tn TS 4.6.2.2b and 4.6.2.3b to include the Residual Heat Removal (RHR) heat exchanger bypass line flow as a component of the total, verified, flow rates.
3.0 EVALUATION The use of a " butterfly" valve in an RHR heat exchanger bypass line results in good flow control but poor leak-tightness as demonstrated by industry experience. The valves in question are 18 inch, 7600 Series, Butterfly
)
Control Valves provided by Fisher Controls and are designated as valve numbers F048A and F0488.
Leak-tightness is not a requirement in this case, as indicated in the February 5,1996 application, in that only 8985 gpm (of the j
total RHR pump flow in the SPC mode) is required for RHR heat exchanger flow i
for the limiting SPC heat removal capability. Heat removal in the SPS mode was found by the licensee to be bounded by the SPC heat removal capability.
As indicated in the February 14, 1996 supplement, testing, by the licensee, during the current refuel outage, resulted in a demonstration that flow through the "A" RHR heat exchanger is 9968 gpm while flow through the "B" heat exchanger is 9648 gpm.
In order to perform this test, a temporary flow monitor was located at the outlet of each RHR heat exchanger. The licensee has committed to perform the RHR heat exchanger flow test, in the SPC mode, once per operating cycle (not to exceed 24 months).
In addition, the licensee has committed to perform valve performance testing of the RHR heat exchanger bypass " butterfly" valves, to test proper valve stroke, on a quarterly basis.
Based upon the above, the NRC staff concludes that the currently demonstrated flow through the RHR heat exchangers is adequate and that bypass flow is not excessive considering the selection of a " butterfly" valve for flow control.
In addition, the proposed periodic testing of RHR heat uchanger flow, and
" butterfly" valve leakage, will detect component degradation in a timely manner. Accordingly, the addition of the words "its associated closed bypass valve," after the words "RHR heat exchanger," to TS 4.6.2.2b and 4.6.2.3b, is acceptable. The NRC staff has also reviewed the proposed changes to the TS Bases for TS 4.6.2 and finds these changes to be acceptable.
4.0 EXIGENT CIRCUMSTANCES
The need to resolve issues associated with RHR heat exchanger bypass leakage was recognized after HCGS was shut down for the current refueling cycle.
a-Since the February 5, 1996, proposed license amendment is needed prior to i
entry into Operational Condition 3 on February 27, 1996, the licensee has requested that the NRC staff consider the application on an exigent basis.
The NRC staff has reviewed the licensee's application for license amendment F
I and finds that (1) the exigent circumstances exist, as provided in 10 CFR 50.91(a)(6), in that the licensee and the Commission must act quickly and that time does not permit the Commission to publish a Federal Reaister notice allowing 30 days for prior public comment, and (2) that the licensee has not I'
i l
l :
' failed to use its best' efforts to make a timely application and avoid creating the exigent circumstance. The Commission noticed the licensee's February 5, 1996 application for license amendment in the Federal Reaister on February 9, 1996 (61 FR 5040), at which time the Commission made a proposed finding that i
the proposed amendment involved no significant hazards consideration and there j
has been no public comment in response to the notice.
5.0 FINAL NO SIGNIFICANT HAZARDS CONSIDERATION
DETERMINATION l
The Commission's regulations in 10 CFR 50.92 provide that the Commission may l
make a final determination that a license amendment involves no significant hazards consideration if operation of the facility in accordance with the 4
amendment:
)
1.
Will not involve a significant increase in the probability or consequences of an accident previously analyzed.
i i
The proposed amendment request changes Surveillance Requirement (SR) 4.6.2.3.b of Technical Specification (TS) 3.6.2.3, Suppression Pool Cooling, and SR 4.6.2.2.b of TS 3.6.2.2, Suppression Pool Spray, to clarify that the intent of these specific SRs is to confim Residual Heat l
Removal (RHR) pump performance during Suppression Pool Cooling (SPC) and Suppression Pool Spray (SPS) operation. The proposed change revises the SRs to include the RHR heat exchanger bypass line, with the bypass valve J
closed, and the RHR heat exchanger in the SPC and SPS flow path used i
during performance of the surveillance.
The RHR system is an accfdent mitigation system. The proposed changes do not change the operation or capabilities of the RHR system in either mode of operation. The proposed changes do not involve any physical changes to the RHR system. The proposed changes merely modify the acceptable flow path for the surveillance tests; the purpose of which is to verify pump performance in these modes of operation. Therefore, the proposed change to the SRs for the SPC and SPS mode of operation of the RHR system j'
will not increase the probability of an accident previously evaluated.
Furthermore, the performance of the RHR system in any of its operational modes will be unchanged by the proposed change. The changes affect only the pump performance SRs for the SPC and SPS modes of RHR system operation. The surveillances tsing changed only modify the acceptable i
flow path used during the performance of the pump performance surveillance. The surveillances still verify that pump performance has not degraded to a point where the accident mitigation function of the i
i system has been compromised. Therefore, the proposed thange will not involve an increase in the consequences of an accident previously evaluated.
- l
2.
Will not create the possibility of a new or different kind of accident from any previously evaluated.
i The proposed change, a clarification of the SPC and SPS mode flow paths for pump performance testing, does not result in a modification of the RHR system, change the method of SPC or SPS operation, or alter the system's effectiveness. Suppression Pool Cooling and Containment Spray 1
Cooling, of which Suppression Pool Spray is a part, are manually initiated actions.
Existing procedures for the initiation of these two modes of operation are unchanged, including the requirement that the Low Pressure Coolant Injection valve is closed before the containment spray valves can be opened.
There are no new failure modes created by the proposed changes and no new accident initiating events are created.
Therefore, the proposed changes will not create the possibility of a new or different kind of accident from any previously evaluated.
3.
Will not involve a significant reduction in a margin of safety.
The proposed changes do not change the operation of the RHR system in any of its modes of operation. The changes only clarify the fact that the purpose of the SRs is to confirm RHR pump performance through the most j
restrictive conditions of the flow path while operating in either the SPC or SPS modes. The changed surveillance still verify that pump performance has not degraded to a point where the original design basis can not be met.
In order to assure the system meets its original design basis, adequate flow through the heat exchanger during surveillance testing will be maintained.
Since the function of all of the operational modes of the RHR system are unaffected by the revised surveillance test flow path, the proposed changes will maintain the existing margin of safety.
Based upon the above, the Commission has made a final determination that the proposed amendment involves no significant hazards consideration.
6.0 STATE CONSULTATION
In accordance with the Commission's regulations, the New Jersey State Official was notified of the proposed issuance of the amendment.
The State official had no comments.
7.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has made a final finding l
11
j e
i
' li that the amendment involves no significant hazards consideration.
Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
i
}
8.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, i
and (3) the issuance of the amendment will not be inimical to the common l
defense and security or to the health and safety of the public.
i Principal Contributor:
D. H. Jaffe Date: February 26. 1996 I
l
_