ML19259B060
| ML19259B060 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 12/04/1978 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19259B057 | List: |
| References | |
| NUDOCS 7901160038 | |
| Download: ML19259B060 (4) | |
Text
s
[
umTro sTATas NUCLEAR REGULATORY COMMisslON 3~
!.($ ) j wAsmucion, o. c.20sse
'...A e SAFETY EVALUATION BY TPE OFFICE OF NUCLEAR REACTOR REGULATION e
SUPPORTING AMENDMENT NO.17 TO LICENSE NO. DPR-72 FLORIDA POWER CO,RPORATION, ET AL CRYSTAL RIVER UNIT 3 NUCLEAR GENERATING PLANT DOCKET NO. 50-302 Introduction By letters dated July 15, October 11, November 8,1977 and February 17, 1978, Florida Power Corporation (FPC) proposed changes to the Crystal
~
River Unit 3 (CR-3) Technical Specifications. These changes pertain to sodium thiosulfate tank operability, emergency core cooling system (ECCS) surveillance, two reactor coolant pump (RCP) operation, condenser temperature monitoring and exhaust gas flow rate monitoring.
We have evaluated the proposed cMnges.
Evaluation 1.
Sodium Thiosulfate Tank Ooerability Paragraph 2.C.(4) of the CR-3 operating license requires that the sodium thiosulfate tank (part of the spray additive system) be isolated until permanent modifications to the chemical additive system have been acproved and installed. FPC has proposed a change to this system which we are currently reviewing.For the period until a modification has been approved and installed, FPC has requested that the existing requirements regarding sodium thicsulfate tank operability (volume, concentrations and flow rates) be deleted.
Since the subject tank is required by license condition to be isolate.d from the spray additive systemty locked closed valves, we find that maintaining the tank in an operable condition is unnecessary and the licensee's proposed change is acceptable.
7 90116 0 0 3g
. 2.
ECCS Surveillance Maintenance of proper flow resistance and pressure drop in ECCS piping utilizing comon headers is necessary to (1) prevent total pump flow from exceeding runout conditions when the system is in its minimum resistance configuration; (2) provide a
. proper flow split between injection points in accordance with the assumptions used in the ECCS. loss of coolant accident (LOCA) analyses, and (3) provide an acceptable level of total ECCS flow to all injection points equal to or above that assumed in the ECCS-LOCA analyses. Many plants have manual and/or motor operated valves in the ECCS piping that have mechanical or electrical stops to ensure that these flow requirements 're satisfied. In view of the safety function associated with the proper setting of these " throttle valves", we requested that licensees detemine if throttle valves were used at their facilities to meet the ECCS flow requirements discussed above and, if so, that they propose surveillance requirements regarding throttle valve settings and system flow verifications.
In its response, FPC stated that motor operated valves in the Low Pressure Injection (LPI) system and stop check valves in the High Pressure Injection (HPI) system were used as throttle valves to meet flow requirements as discussed previously. FPC proposed a change which would require verification of the correct position of each mechanical position stop for the HPI stop check valves and trification of proper operation of the flow switches for the LPI itor operated throttle valves under the following conditions:
1.
Prior to placing the applicable system (HPI or LPI) back in service following periodic valve stroking or maintenance on these valves, and 2.
At least once every 18 months.
In addition, FPC proposed a requirement to perfom a flow balance test to confim specified minimum flow rates following completion of HPI or LPI system modifications that alter system flow characteris tics.
DHV-110 and 111 are the motor operated valves in the LPI system which act as automatic flow controllers in the discharge of the LPI pumps. These valves prevent total pump flow from exceeding runout conditions. For the flow verification test, FPC proposed
. a minimum acceptable flow limit of 2000 gpm.The previously accepted operating range for flow control was 2800-3100 gpm.
In view of the upper bound on acceptable flow due to LPI pump runout considerations, we have detennined that the maximum acceptable flow (3100 gpm) should be included as a limit for this flow verification test. This change has been discussed with FPC and is acceptable.
MUV-2, 6 and iC are the stop check valves in the HPI system used to assure an acceptable level of HPI flow to all injection points. FPC has proposed a minimum acceptable flow for each injection leg of 250 gpm at 600 psig backpressure. These valves do not function to limit flow for pump runout considerations, and the minimum ficw specified satisfies current ECCS requirements.
Manual adjustment of flows for certain small breaks, as discussed in the Exemption issued September 1,1978, is accomplished using other HPI system valves. The addition of these surveillance requirements does not affect the terms or conditions of the September 1, 1978 Exemption.
Based on the above, and because the proposed requirements will provide sufficient additional assurance that the ECCS will function as intended, we have determined that the proposed change is acceptable.
3.
Two RCP Operation The current CR-3 Technical Specifications contain limits associated with power operation when only two of four reactor coolant pumps are operating. Paragr'tph 2.C.(3) of the CR-3 license, however, prohibits power operation with less than three of RCP's in operation until safety analysis of such operations have been submitted and approved. FPC has proposed a change deleting all references to two pump operation at power stating that this will make it clearer that operation in that mode is not allowed. Since two RCP operation at power will continue to be prohibited by both the license condition and now by the Technical Specifications, those limits dealing with two RCP operation perfonn no function with respect to reactor safety and their deletion is acceptable.
4.
Condenser Temeerature Monitoring Appendix B Technical Specification 2.1.1 requires monitoring of the condenser temperature rise by using detectors located in the condenser inlet and outlet water boxes as originally installed.
FPC has found that one of the detectors reads higher than the average discharge temperature and could cause unnecessary derating of the unit. Therefore, FPC has proposed to move the temperature monitoring instruments downstream to where a representative average discharge temperature can be obtained. We approve of the change as its purpose is to more accurately monitor the unit aT as is the intent of this requirement. This change does not involve a change to the Limiting Conditions for Operation.
4 5.
Condenser Vacuum Pumo Exhaust Flow Rate Monitoring Section 2.4.2.G of the Appendix B Technical Specifications states that gaseous release flows, except from the turbine building ventilation exhaust, shall be continuously measured. FPC has proposed to change this requirement to a flow detemination every shift for the condenser vacuum pump exhaust, since this exhaust was not designed to have a continuous flow rate recorder.
The subject pump operates in either the normal operation or hogging mode.
In normal operation. the flow rate is constant and greater than the flow rate in the hogging mode. This is possible by compensating air drawn from the condenser with air drawn from the turbine building. The hogging mode is used infrequently for short periods of time following extended shutdowns.
Since the flow rate during nomal operation is constant, a measurement of flow once per shift coupled with the time of operation, will provide adequate data for release rate determinations and is therefore acceptable.
Environmental Consideration We have determined that the amendment does not authorize a change in effluent types or total amounts nor an increase fn power level and will not result in any significant environmental impact. Having made this detemination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact and, pursuant to 10 CFR 551.5(d)(4), that an environmental impact statement, or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of this amendment.
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission's regulations and the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Dated: January 4,1979