ML20215G164
| ML20215G164 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 06/04/1987 |
| From: | Cockfield D PORTLAND GENERAL ELECTRIC CO. |
| To: | Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| NUDOCS 8706230143 | |
| Download: ML20215G164 (4) | |
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RECEIVED F
NRC l_
m [C 1997 Jg g A II: IO Portland GeneralBectricCarey David W. Cockfield Vice President, Nuclear bO/0// y June 4, 1987 Trojan Nuclear Plant Docket 50-344 i
License NPF-1 Mr. John B. Martin Regional Administrator, Region V U.S. Nuclear Regulatory Commission Creeksido Oaks Office Park 1450 Maria Lane, Suite 210 Walnut Creek CA 94596-5368
Dear Mr. Martin:
TROJAN NUCLEAR PLANT Applicability of Technical Specification 3.0.3 for Hydrostatic Testing of Reactor Coolant System and Attached Systems Pursuant to discussions with members of your staff and the Office of Nuclear Reactor. Regulation, this letter advises you of our plans for performing a hydrostatic test of the Reactor Coolant System (RCS) and, attached systems and the necessity of temporarily entering Limiting Condition for Operation (LCO) 3.0.3 of the Trojan Technical Specifications. The test will be performed at the end of the current refueling outage.
The hydrostatic test will demonstrate the structural integrity of welds associated with several Plant modifications, including the installation of new flow control throttle valves in Emergency Core Cooling Systems (ECCS).
Four of these valves were installed in a portion of the Safety Injection (SI) System which is not isolable from the RCS; therefore, the hydrostatic test will pressurize piping in both systems. The test must be performed in Mode 3 to comply with the primary-to-secondary differential precouro limi-tation across the steam generator tube shoot of 1600 psid, as specified in Section 1.2 of'the Technical Manual for Steam Generators (E201A-D). The system configurations will require shutting the SI cold leg common injec-tion header isolation valve (MO-8835) to establish the test pressure boundary, thereby eliminating the flowpath for both SI pump discharge trains required by ECCS Surveillance Requirement 4.5.2.a.c of the Technical Specifications. As a result, LCO 3.0.3 becomes the coc. trolling Technical Specification. With MO-8835 shut, LCO 3.0.3 requires that the Plant be placed in Mode 4 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> if correct.ive measures are not completed.
8706230143 B70604 DR ADOCK 050 4,
MO/
121 S W Salmon Stmet. Portland. Oregon 97204
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Porutvid W MCeiiiptin3r
~Mr.' John B. Martin
' June 4, 1987
'Page 2 The period of. time spent in this condition during the test will be minimized-and'will not exceed this 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> limit.
A more detailed discursion of the test and associated safety considerations
.is attached. We-would be pleased-to answer any questions you might have regarding this matter.
Sincerely, Attachment c:
Mr. Terence Chan Project Directorate No. 3 U.S. Nuclear Regulatory Commission Mr. R. C. Barr NRC Resident Inspector Trojan Nuclear Plant
d E
4 Trojan Nuclear Plant Mr. John B. Martin i
Docket 50-344 June 4, 1987 l
License NPF-1 Attachment Page 1 of 2 SAFETY CONSIDERATIONS ASSOCIATED WITH THE HYDROSTATIC TEST OF THE REACTOR COOLANT SYSTEM AND ATTACHED SYSTEMS During the 1987 refueling and maintenance outage, modifications were per-formed affecting the pressure boundaries of the Reactor Coolant System (RCS)
I and attached systems.
In accordance with Technical Specification 4.0.5 and l
Section IWA-4210 of the American Society of Mechanical Engineers (ASME)
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Boiler and Pressure Vessel Code, the new welds forming the pressure retain-ing boundary must be subjected to a hydrostatic pressure test. This test i
will demonstrate the structural integrity of ASME Class 1 (RCS) and adjacent l
ASME Class 2 piping. The Class 2 piping is separated from the RCS by check valves which must be bypassed to pressurize appropriate sections of piping.
The governing test pressure is RCS pressure at 1.02 times the normal operating pressure of 2235 psig.
Full Class 2 test pressure cannot be used since the separating check valves are oriented for flow into the RCS and the pressure would 2xceed RCS limits per ASME Section XI, Article IWB-5000.
Temporary Plant Test (TPT) 196, Revision 0, Reactor Coolant System Hydrostatic Test, has been written for this test.
The test is to be performed while in Mode 3 at the conclusion of the refueling outage. The test must be performed in either Modes 1, 2, or 3 in order to comply with the primary-to-secondary differential pressure limita-tion across the steam generator tube sheet of 1600 psid as specified in Section 1.2 of the Technical Manual for Steam Cenerators (E201A-D).
In order to establish a test pressure boundary which includes four new flow l
control throttle valves installed in the Safety Injection (SI) System, the SI cold les common injection header isolation valve (MO-8835) must be shut.
(The SI hot leg injection isolation valves, MO-8802A and MO-8802B, will remain in their normal shut position during the test.) In the Trojan Technical Specifications, Emergency Core Cooling System Surveillance l
Requirement 4.5.2.a.c requires MO-8835 to be open (with power removed) for automatic system operation during Modes 1, 2, or 3.
Therefore, closure of f
3 this valve (during the test) results in entering Limiting condition for Operation (LCO) 3.0.3 of the Trojan Technical Specifications.
During the period when the valve is closed (not to exceed 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />), an operator will i
be stationed to immediately reposition the valve manually should it be l
necessary.
An appendix to the test procedure provides restoration instruc-f tions for both a small break Loss-of-Coolant Accident (LOCA) and large j
break LOCA. The injection flowpaths from the Residual Heat Removal System, g
the SI accumulators, and the centrifugal charging pumps are not affected by l
this test.
During a safety injection, flow will be provided immediately by l
these systems.
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The hydrostatic test is scheduled to be performed at the end of the current
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of 557'F.
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refueling outage. RCS temperature will be near no-load Tave The reactor will remain suberitical with control rods fully inserted l
throughout the test. The decay heat load will be low since the Plant has j
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I
t Trojan Nuclear Plant Mr. John B. Martin Docket 50-344 June 4 1987 License NPF-l' Attachment Page 2 of 2 I
been shut down since April 1, 1987 and 48 fuel assemblies have been replaced with new ones.and nine fuel assemblies have been replaced with ones from' earlier cycles with an insignificant amount of decay heat. For 1
.the Trojan LOCA analysis, decay heat and initial fuel rod temperatures are based on operation at 102 percent power for more than 60 days.
Because 1
Trojan has been shutdown for more than 60 days, the decay heat is less than 5 percent of the decay heat assumed in the LOCA. Fuel rod temperatures have equalized to the Reactor Coolant System average temperature. The consequences of a LOCA depend upon decay heat power icvel, initial core temperatures, and injection flow rates. With the substantial reduction in decay. heat. power level, the required flow rates are only a small fraction of those assumed in the LOCA analysis. Prior to the hydrostatic test, nondestructive examination, including liquid penetrant tests and radiography, of.the welds associated with installation of the throttle i
valves will have been satisfactorily completed.
1 In. view of the above, the test will not increase the probability or 1
consequences of an accident or equipment malfunction previously evaluated l
I in the Final Safety Analysis Report (FSAR). The proposed test does not degrade the primary coolant pressure boundary, but rather.verifles its integrity.
Since the test will be performed in Mode 3 with low decay heat l
generation due to the installation of new fuel and the long shutdown l
period, the consequences of a LOCA are well bounded by existing analyses.
.The proposed test will not create the possibility of an accident or equip-i ment malfunction not previously analyzed. During the short period of time MO-8835 is required to be shut, an operator will be stationed at the valve to manually open it if necessary. This precautionary measure ensures valve opening capability, even in the event of electrical malfunction or loss of power.
l The margin of safety, as defined in the bases of the Technical Specifica-tion, will not be reduced by the performance of this test since the flow path remains available and the low decay heat generation rate makes the l
small delay in the initiation of cold les safety injection acceptable.
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