ML20197J679

Responds to Items Identified in Eg&G Rept Reviewing Util 851228 Submittal on Meeting Requirements of Reg Guide 1.97, Per Generic Ltr 82-33 & Suppl 1 to NUREG-0737

ML20197J679
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	05/13/1986
From:	Withers B PORTLAND GENERAL ELECTRIC CO.
To:	Varga S Office of Nuclear Reactor Regulation
References
RTR-NUREG-0737, RTR-NUREG-737, RTR-REGGD-01.097, RTR-REGGD-1.097 GL-82-33, TAC-51362, NUDOCS 8605200139
Download: ML20197J679 (10)

Text

,

- ammma

- Pbetisuid W M C 0iiipts y

- E bart D Wahers Vce Presdort May 13, 1986 Trojan Nuclear Plant Docket 50-344 License NPF-1 Director of Nuclear Reactor Regulation ATTN: Mr. Steven A. Varga Director, PWR-A Project Directorate No. 3 U.S. Nuclear Regulatory Commission Washington DC 20555

Dear Sir:

Regulatory Guide 1.97 Review Generic Letter 82-33 dated December 17, 1982, " Supplement 1 to NUREG-0737 Requirements for Emergency Response Capability", required licensees to sub-mit a report describing how they intend to meet the requirements of Regula-tory Guide 1.97, " Instrumentation for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident". Our December 28, 1985 letter transmitted the requested. report regarding the post-accident monitoring capability at Trojan. Your March 3, 1986 letter to Mr. Bart D. Withers transmitted a report prepared by EG&G Idaho, Incorporated documenting your review of our Regulatory Guide 1.97 submittal. Attachment A to this letter is our response to the 12 items identified in the EG&G report conclusion section as requiring further j justification or clarification.

i Attachment B to this letter documents a change in our commitment to environmentally qualify the accumulator isolation valves and position indication along with justification for this change.

Sincerely, Bart D. Withers Vice President Nuclear Attachments I

B605200139 860513 PDR ADOCK 05000344 (pg )

p PDR i, I l

= 4

• e ,

= =. -

7 Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 May 13, 1986 License NPF-1 Attachment A Page 1 of 8 RESPONSE TO OPEN ITEMS IDENTIFIED IN REVIEW OF TROJAN COMPLIANCE WITH REGULATORY GUIDE 1.97

1. Comment: Neutron flux - the licensee should install a redundant channel of Category 1 instrumentation for this variable.

' , Response: Reactivity control is automatically achieved and main-tained by reactor trip and injection of boron by the safety injec-tion system. Reactor trip is verified by rod bottom indication as an.immediate operator action. Rod bottom indication is expected to be received prior to the instrumentation being significantly degraded by a harsh environment. Automatic post-accident boron injection flow rates and concentrations are designed to provide adequate shutdown margin for accidents without measuring the boron concentration. Boron injection of 2000 ppm from the refueling water storage tank and accumulators can be verified with qualified Category 1 and 2 instrumentation.

Neutron flux could be considered a backup means of verifying automatic reactor shutdown and detecting and verifying reactivity control. As such, neutron flux would be classified as Category 2 instrumentation not requiring' redundant, qualified channels.

The existing source range detectors consist of three systems which are powered from Class 1E tsitery-backed buses.

Two source range monitors have a range of 1 to 106 counts per secon'd . Two intermediate range monitors have a range of 10-11 to 10-3 amps and overlap both source range and power range indica-tion. Four power range monitors have a range of 0 to 200 percent.

These monitors provide an equivalent range of 10-9 percent to 200 percent full power. All ranges are indicated and any channel may be recorded. Although the existing neutron flux monitors are not environmentally qualified for post-accident monitoring, they are qualified to perform their immediate safety function of reactor protection. For long-term monitoring, a single qualified channel is considered adequate.

The installation of one fully qualified channel for neutron flux, along with the existing means of verifying reactivity control, meets the intent of Regulatory Guide 1.97 for this variable.

Any boron dilution would be detected by periodic sampling using the Post-Accident Sampling System (PASS), which has been reviewed and approved under NUREG-0737, Item II.B.3.

i

~ ^ ^ ^ "

Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 May 13, 1986 License NPF-1 Attachment A.

Page 2 of 8

2. Comment: Condenser air removal exhaust noble gas - the licensee should provide the information required by Section 6.2 of NUREG-0737, Supplement 1 for this variable and identify and justify any deviations.

3. Comment: Containment effluent radioactivity-noble gas - the licensee should provide the information required by Section 6.2 of NUREG-0737, Supplement 1 for this variable and identify and justify any deviations.

4. Comment: Effluent radioactivity-noble gas - the licensee should provide the information required by Section 6.2 of NUREG-0737, Supplement 1 for this variable and identify and justify any deviations.

11. Comment: Noble gases and vent flow rates - the licensee should 1 provide the information required by Section 6.2 of NUREG-0737, Supplement 1 for these variables and identify and justify any deviations.

Response: See attached Table A-1. The main condenser air discharge noble gas monitor (PRM-6), Containment purge exhaust monitor (PRM-1), and Auxiliary Building exhaust monitor (PRM-2) do not meet Regulatory Guide 1.97 Category 2 environmental qualification requirements.

As stated in Section 4.2 of previously submitted PGE-1043, " Accident Monitoring Instrumentation Review", it is considered appropriate to recategorize the noble gas effluent instruments from Category 2 to Category 3 on the basis of previous requirements specified by NUREG-0737.

With respect to the noble gas effluent monitors, PGE has adopted the position that Regulatory Guide 1.97 Category 3 design and qualifica-tion criteria will be applied to this equipment. This position is justified on the basis that:

a. Category 3 criteria are equivalent to the NUREG-0737 criteria under which this equipment was installed. The post-accident environment is the specified service environment this instru-mentation was selected to withstand.

b. Effluent radiation monitors are not necessary for the safe shutdown of the reactor, long-term core cooling, or Containment of radioactive material following an accident.

k . :,

Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 May 13, 1986 License NPF-1 Attachment A Page 3 of 8

'1

c. More rigorous demonstration of environmental qualification as l would be required by imposition of Category 2 criteria is not i

justified by the importance of the safety function this equipment performs.

The noble gas effluent monitors provide readouts in counts per minute (cpm) and mR/hr. Conversion factors are readily available in the control room to convert cpm and mR/hr to pCi/cc for the specific detectors. The converted ranges cover those prescribed by Regulatory Guide 1.97 except the Auxiliary Building exhaust which has an upper limit of 300 pC1/cc. _ Noble gas effluent monitor readout units and Auxiliary Building effluent monitor range have been reviewed and accepted as deviations to NUREG-0737 by NRC letter to B. D. Withers dated December 23, 1981.

Noble gas vent flow instruments do not meet the Regulatory Guide 1.97 range of 0 to 110 percent.

The existing condenser air discharge flow instrument is inoperable and will be repaired or replaced by the end of the 1987 refueling outage. The instrument range will cover approximately 0 to 110 per-cent of the design flow rate. Standard industrial grade equipment, suitable to provide sufficiently accurate responses to perform the intended function in the environment to which they will be exposed during accidents, will be provided. This is consistent with PGE's position that this variable is Category 3, as is the noble gas monitor.

Containment effluent flow indication is provided on a recorder in the control room with a range of 0 to 70,000 cfm. This flow is measured downstream of the radiation monitor in the Containment purge exhaust duct, which is designed for 50,000 cfm normal opera-tion. The existing instrumentation covers 0 to 140 percent of the design flow. The Trojan Emergency Procedures provide direction to assume conservative flow rates for calculating releases when

reliable flow indication is not available.

The Auxiliary Building accident effluent release flow rate is deter-mined by the number of exhaust fans running. Release rates are calculated based on the maximum design flow rate (26,000 cfm) per fan multiplied by the number of exhaust fans running. Local flow meters are available for each fan. This method of determining Auxiliary Building effluent release flow rate was discussed in a meeting with PGE, NRC, and EG&G on March 23, 24, and 25, 1982, with respect to license amendment 50 (10 CFR 50 Appendix I compliance),

with no exceptions taken.

Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 May 13, 1986 License NPF-1 Attachment A Page 4 of 8

5. Comment: Quench tank temperature - since the tank design pressure and rupture disk release pressure is 100 psig, instrumentation with a range up to and including 338'F should be provided.

Response: The existing pressurizer relief tank (PRT) temperature range of O'F to 300*F is adequate for' the intended function of the '

instrument. During normal operation, the PRT temperature is used to determine if PRT cooling is required to maintain the temperature below 200*F. PRT temperature is used in conjunction with pressure and level to monitor for abnormal conditions during an accident. A temperature near 300*F would indicate abnormal conditions. Tempera-ture indications above 300*F would not provide any useful informa-tion to.the operator. As the temperature approaches 300*F, abnormal conditions would be assessed and the intended function of the instrument is accomplished.

6. Comment: Steam generator level - the licensee should upgrade the wide range instrumentation to Category 1 requirements.

Response: As previously stated in our submittal and acknowledged in

.your review, steam generator wide range level instrumentation will be upgraded to Category 1. This modification will be completed by the end of the 1987 refueling outage.

7. Comment: Steam generator pressure - the licensee should either upgrade the existing 0 to 1500 psig instrumentation to meet Category 1 requirements or expand the range of the Category 1 instrumentation.

Response: Category 1 0-1200 psig pressure instrumentation is provided. One 0-1500 psig transmitter per steam line is installed.

'These transmitters are powered by reliable diesel generator backed buses. The indication is continuous on a dedicated indicator for each transmitter. The transmitters are located in the Turbine Building, which is considered a mild environment except for a main feed or steam line break in the Turbine Building and would be quali-fled to perform for all other accidents. PGE considers the existing instrumentation adequate to provide the necessary information for operator response to accident conditions.

Steam generator pressure below 1230 psig (the highest safety valve setpoint) does not require any operator action at Trojan. Responses-

. to steam pressure indication above 1230 psig are beyond the design basis for'the Plant and should not require qualified instrumenta-tion. Pressure indication above 1200 psig for a main feed or steam line break would not provide any useful information for the operator to respond to.

7 Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 May 13, 1986 License NPF-1 Attachment A

- Page 5 of 8

8. Comment: Condensate storage tank - the licensee should provide seismically qualified instrumentation for this Type A variable.

Response: Redundant, Class 1E, seismically qualified instrumenta-

. ' tion is being provided for the condensate storage tank level indica-tion. This modification will be complete by the end of the 1986 1 refueling outage.

t

9. Comment: Containment spray flow - the licensee should provide additional information for the alternate instrumentation for this variable.

Response: Spray pump discharge pressure alone does not indicate proper system flow; pump discharge pressure, sodium hydroxide flow

.and valve position are used in combination. Design conditions for-the Containment spray system are 2800 gpm at a pump discharge pressure of approximately 215 psig. Indication of proper spray flow rate is also verified by sodium hydroxide flow indication (35-40 gpm, design). Spray pump discharge pressure, sodium hydroxide tank level and flow-indication are Category 2. After the spray additive tanks are isolated, the only way spray flow could be degraded would be the closure of the Containment spray isolation valve, loss of pump suc-tion, or loss or degradation of the pump. Increased pump discharge pressure along with isolation valve closed indication or decreased pump discharge pressure would indicate a decrease in Containment spray flow. Pump discharge pressure close to 215 psis, along with containment spray isolation valve open indication, provides 4 indication of proper Containment spray flow.

, 10. Comment: Component cooling water flow to engineered safety feature

system components - the licensee should verify that the alternate

! instrumentation is Category 2.

. Response: The alternate instrumentation, CCW pump discharge pressure transmitters and CCW heat exchanger inlet and outlet

[

temperature indicators, meet Category 2 requirements.

12. Comment: Particulates and halogens - the licensee should provide the information required by Section 6.2 of NUREG-0737, Supplement 1 for this variable and identify and justify any deviations.

Response: See attached Table A-1. Justification for deviation from flow rate range is contained in Comments 2, 3, 4, and 11 response.

i r

l l

Trojan NucicEr Pltnt Mr. Stavin A. Vnrgs Docket 50-344 May 12, 1986 Licen o NPF-1 Attachment A TABLE A-1 Page 6 of 8 Variable NRC Troian Auxilicry Building - Noble Gas and Vent Flow Rate (E-3C)

C:,ttg ry 2 3 QA Yes Yes Instrument Range 10-6 to 103 pCi/cc 10-6 to 102 pCi/cc 0 to 110% flow Note 1 Environmental Qualification Yes No Saismic Qualification No No Schedule -

Complete Redundant No No Power Supply Highly reliable Highly reliable Contral Room Indication Continuous recording Continuous count rate recording TSC -

EOF -

Comments -

Cond:nrer Air Removal System EXH -

Noblo Gas and Vent Flow Rate (E-3D)

C:trg ry 2 3 QA Yes Yes In;trument Range 10-6 to 105 pCi/cc 10-6 to 105 pCi/cc 0 to 110% flow Note 1 Envir nmental Qualification Yes No S31smic Qualification No No Sch:dule - End of 1987 outage R;dundant No No Power Supply Highly reliable Highly reliable control Room Indication Continuous recording Continuous count rate recording TSC -

E!F -

C:mments -

Cotunon Plant Vent - Noble Gas and Vent Flow Rate (E-3E)

C;tigory 2 QA Yes Instrument Range 10-6 to 103 pCi/cc 0 to 110% flow Environmental Qualification Yes Solo ic Qualification No Schidule -

Redundant No Power Supply Highly reliable Crntrol Room Indication Continuous recording TSC -

EOF -

Cotanents - Not in design.

Trojan Nuclc:r Pl:nt Mr. Stivsn A. Virgs Dock t 50-344 May 12, 1986 Licen o NPF-1 Attachment A TABLE A-1 (cont'd) Page 7 of 8 Variable NRC Trojan Vent From S/G Safety Relief Valves of Atmospheric Dump Valves - Noble cas (E-3F)

C ttstry 2 3 QA Yes Yes Inc,trument Range 10-1 to 103 pCi/cc 10-1 to 103 pCi/cc 0 to 110% flow Note 2 Envir:nmental Qualification Yes Yes*

Saismic Qualification No No Schedule - Complete Redundant No No Power Supply Highly reliable Highly reliable Contr31 Room Indication Continuous recording Continuous dose rate recording TSC -

EOF Comments -

• Environmentally qualified for steam generator tube rupture only.

Contcinment or Purge Effluent - Noble Gas rnd Vent Flow Rate (E-3A)

Catsgsry 2 3 Yes Yes QA Instrument Range 10-6 to IC I' pCi/cc 10-6 to 105 pCi/cc 0 to 110% flow Note 1 Environmental Qualification Yes No Scismic Qualification No No Schedule - Complete R dundant No No Power Supply Highly reliable Highly reliable C ntesl Room Indication Continuous recording Continuous count rate recording TSC EOF Comments -

Trojan Nucloce Plant Mr. Stcv:n A. Vcrgs Docket 50-344 May 12, 1986

- Litenr, NPF-1 Attachment A TABLE A-1 (cont'd) Page 8 of 8 Variable NRC Trojan All Cther Identified Release Points -

Noble cas and Vent Flow Rate (E-3C)

C;tegtry 2 QA Yes In;trument Range 10-6 to 102 pCi/cc l

0 to 110% flow Envir:nmental Qualification Yes S;ismic Qualification No Schedule -

Redundant No Power Supply Highly reliable Control Room Indication Continuous recording

'TSC -

ROF -

Conments - No other release points identified.

All Identified Plant Release Points Particulates and Halogens (E-4)

C;tsg:ry 3 3 QA No No In trument Range 10-3 to 102 pCi/cc 10-3 to 102 pCi/cc 0 to 110% flow Note 1 Envir:nmental Qualification No No l S;ismic Qualification No No Sch;dule - Complete R:dundant No No l P;wer Supply -

C:ntrol Room Indication Not required (portable) Crab sample TSC -

1 E!F -

l Comments -

N2ts 1: Flow instruments and ranges are discussed in response to Comments 2, 3, 4, and 11.

C;to 2: Flow rate is based on 86,000 lbm/hr for each safety valve.

c- - - - -

Trojan Nuclear Plant Mr. Steven A. Varga Docket 50-344 May 13, 1986 License NPF-1 Attachment B Page 1 of I COMMITMENT CHANGE FROM ORIGINAL REGULATORY GUIDE 1.97 SUBMITTAL Accumulator isolation valve and position indication: In the original Trojan Regulatory Guide 1.97 review submittal, PGE committed to provide Category 2 accumulator pressure indication, discharge isolation valves and isolation valve position indication. Upon further review of necessary accumulator status instrumentation, PGE concludes that Category 2 pressure indication alone provides sufficient information to determine accumulator availability and status. This results in a deviation to Regulatory Guide 1.97 not previously discussed.

Deviation: Accumulator isolation valve position indication does not meet Category 2 environmental qualification requirements.

Justification: Accumulator isolation valves are administratively controlled and maintained open with power removed during operation.

These valves are not required to change position during an accident for the accumulators to fulfill their safety function.

Accumulator pressure is the primary source of information for control room indication of accumulator safety function operation and will meet Category 2 requirements. The isolation valve position is not available with power removed from the valve, however, valve position is verified open by administrative controls. PGE considers this appropriate for this variable.

a JDD/kal 0843W.586 1

%