ML20140D822

Documents 851216 Telcon & Addl Response to Item 1.2 of Generic Ltr 83-28, Post-Trip Review:Data & Info Capabilities. NRC Agreed That Final SER Would Be Published to Close Out Issue

ML20140D822
Person / Time
Site:	Millstone
Issue date:	01/10/1986
From:	Opeka J NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	Charemagne Grimes, Thadani A Office of Nuclear Reactor Regulation
References
A05364, A5364, GL-83-28, TAC-53607, NUDOCS 8602030120
Download: ML20140D822 (11)

Text

I NORTHEAST UTILITIES m , , o u w w mo ew. u=~

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P O BOX 270 r..s., ....a H ARTFORD, CONNECTICUT 06141-0270 L L J 'f.T.Z," C.', $'~. (203) ses-sooo January 10, 1986 Docket Nos. 50-245 50-336 A05364 Office of Nuclear Reactor Regulation Attn: Mr. Christopher I. Grimes, Director Integrated Safety Assessment Project Directorate Division of PWR Licensing - B Mr. Ashok C. Thadani, Director PWR Project Directorate No. 8 Division of PWR Licensing - B U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Gentlemen:

Millstone Nuclear Power Station, Unit Nos. I and 2 Request for Additional Information - Generic Letter 83-28, Item 1.2 In a letter dated November 6,1985(l), the Staff provided a draf t Technical Evaluation Report (TER) representing the Staff's initial judgement of our response to Generic Letter 83-28, Item 1.2 for Millstone Unit Nos.1, 2 and 3.

The Staff also requested a telephone conference to review the open items outlined in the draf t TER.

In a December 16, 1985 telephone call, representatives of Northeast Nuclear Energy Company (NNECO) provided the Staff with additional information on the open items from the draf t TER for Millstone Unit Nos. I and 2. Based on this additional information, the Staff concluded that NNECO's verbal responses adequately addressed the Staff's concerns. The Staff and NNECO agreed that upon receipt of NNECO's formal documentation of the additional information, the Staff would publish a final Safety Evaluation I?cport (SER) satisfactorily closing out this issue for Millstone Unit Nos. I and 2.

Attachments I and 2 to this letter formally document the additionalinformation provided in the December 16,1985 telephone call, for Millstone Unit Nos. I and 2 respectively.

(1) 3. A. Zwolinski letter to 3. F. Opeka dated November 6,1985, "Draf t Technical Evaluation Report (TER) for ATWS Item 1.2 (Generic Letter 83-28)."

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We trust this submittal addresses all of the Staff's o ,cerns on this issue so that a final SER can be issued.

Very truly yours NORTHEAST NUCLEAR ENERGY COMPANY

. F. ChJu V

3. F. Opeka>

Senior Vice President

. o Docket No. 50-245 Attachment 1 Millstone Unit No.1 Additional Information on Generic Letter 83-23, Item 1.2 January,1986

In the NRC's draf t Technical Evaluation Report (TER) of NNECO's response to Generic Letter 83-28, Itern 1.2 (Post-Trip Review: Data and Information Capabilities) for Millstone Unit 1, the Staff reported NNECO's response was

, unsatisfactory in the following areas:

o Parameters recorded o Time history recorders performance characteristics o Data retention capability In a December 16, 1985 telephone call, NNECO provided the Staff with additional information on these items. This information is documented below as part of NNECO's formal response to Generic Letter 83-23, Item 1.2.

Parameters Recorded in Table 1, the NRC provided a list of desirable BWR parameters for Post-Trip review with the circled parameters designating parameters the NRC required further information on. This information is provided below.

a) Safety Injection - Presently, LPCI is recorded on a Strip Chart Recorder while core spray system initiation is only indicated in the control room.

b) Containment Isolation - Containment isolation status is recorded on the Sequence of Events Recorder. MSIV's position will be recorded on the Sequence of Events Recorder when the new process computer is installed.

c) Turbine Trip - Turbine trip is recorded on the Sequence of Events Recorder, d) Control Rod Position - Time of scram initiation will be recorded on the Sequence of Events Recorder on the new process computer. Scram times (time for rods to be fully inserted) will be recorded on the Rod Worth Minimizer computer. Thus, indirectly, the time at which all rods become fully inserted can be ascertained from available data, e) Drywell Pressure - Drywell pressure is recorded on a Strip Chart Recorder and is planned to be incorporated into the SPDS.

f) Suppression Pool Temperature - Suppression pool temperature is recorded on a Strip Chart Recorder with a high temperature alarm recorded on the Sequence of Events Recorder.

g) Turbine Stop Valve / Control Valve Position - Turbine stop valve closure is recorded on the Sequence of Events Recorder. Control valve closure is recorded on a Strip Chart Recorder only when the turbine is on line.

h) Turbine Bypass Valve Position - Turbine bypass valve position is recorded on a Strip Chart Recorder.

i) Scram Discharge Level - Scram discharge volume high and high-high level alarms are recorded on the Sequence of Events Recorder, j) Condenser Vacuum - Condenser low vacuum and low vacuum turbine trip alarms are recorded on the Sequence of Events Recorder.

Time History Recorders Performance Characteristics The new process computer for Millstone 1, which is scheduled to be operational in 1988, is being procured to have one second resolution for analog data points and four msec resolution for digital points. The computer will have the capacity to store data for 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> pre-trip to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> post-trip.

Data Detention Capability Scram reports are retained for the life of the plant. A procedure change will be initiated to attach the Pre-Post Trip Analog Reports to the Scram Reports for life of plant storage.

- Millstone 1 Desirable BWR Parameters for Post-Trip Review (circled parameters are not recorded)

SOE Time History Recorder Recorder Parameter / Sional x Reactor Trip Safety Injection 8xx x

Containment Isolation Turbine Trip 8x Control Rod Position x (1) x Neutron Flux, Power x (1) Main Steam Radiation (2) Containment (Dry Well) Radiation 4.-

x (1) @ Drywell Pressure (Containment Pressure)

@ Suppression Pool Temperature Primary System Pressure x (1) x x (1) .x Primary System Level x MSIY Position Turbine Stop Valve / Control Valve Position

@(1)

@ Turbine Bypass Valve Position x Feedwater Flow x Steam Flow (3) Recirculation; Flow, Pump Status

@(1) Scram Discharge Level Condenser Vacuum

@(1) x AC and DC Syste= Status (Bus Voltage)

(3)(4) Safety Injection; Flow. Pump / Valve Status x Diesel Generator Status (On/Off, Start /Stop)

(1): Trip parameters.

(2): Parameter may be recorded by either an SOE or time history recorder.

(3): Acceptable recorder options are: (a) system flow recorded on an SOE recorder, (b) system flow reco,rded on a time history recorder, or (c) equipment status recorded on an SOE recorder.

(4): Includes recording of parameters for all applicable systems from the following: HPCI, LPC1, LPCS, IC, RCIC.

TABLE 1

Docket No. 50-336 Attachment 2 Millstone Unit No. 2 Additional Information on Generic Letter 83-28, Item 1.2 i

1 January,1986

In the NRC's draf t Technical Evaluation Report (TER) of NNECO's response to Generic Letter 83-28, item 1.2 (Post-Trip Review: Data and Information Capabilities) for Millstone Unit 2, the Staff reported NNECO's response was unsatisfactory in the following area:

o Parameters recorded o Time history recorders performance characteristics o Data retention capability In a December 16, 1985 telephc,ne call, NNECO provided the Staff with additional information on these items. This information is documented below as part of NNECO's formal response to Generic Letter 83-23, item 1.2.

Parameters Recorded in Table 2, the NRC provided a list of desirable PWR parameters for Post-Trip review with the circled parameters designating parameters the NRC required further information on. This information is provided below.

a) Reactor Trip - Reactor trip is recorded on the Sequence of Events Recorder.

b) Safety injection - Safety injection does not initiate a reactor trip, however both safety injection initiators (high containment pressure or low pressurizer pressure) do initiate trips and are recorded on the Sequence of Events Recorder.

c) Containment Isolation - Containment isolation is recorded on the Sequence of Events Recorder.

d) Turbine Trip - TurWne trip event is recorded on the Sequence of Events Recorder, e) Control Rod Position - Control rods fully inserted is recorded on the Sequence of Events Recorder.

f) Neutron Flux, Power - Neutron flux / power will be recorded on the Sequence of Events Recorder when a neutron flux / power trip is initiated.

in addition neutron flux / power is recorded on the Pre-Post Trip Analog Recorder.II) g) Containment Pressure - Containment pressure will be recorded on the Sequence of Events Recorder when a high containment pressure trip is initiated. In addition, a wide range value (0-250 psig)is recorded on a Strip Chart Recorder.

(1) Presently, the Pre-Post Trip Analog Recorder for Millstone Unit 2 has a sample interval of 1.5 minutes for the time period 5 minutes to 1 minute pre trip and 15 sec for the interval 1 minute pre-trip to 5 minutes post-trip. For a description of the sample intervals to be utilized in the new process computer, please refer to our discussion on time history performance characteristics.

h) Containment Radiation - Low range measurement of containment radiation

, is measured on a Strip Chart Recorder and high range alarm is recorded on the Sequence of Events Recorder.

1) Containment Sump Level - Wide range containment sump level (0-7f t) is measured on a Strip Chart Recorder j j) Primary System Pressure - High or low primary system pressure is a reactor trip and is recorded on the Sequence of Events Recorder. In i addition, primary system pressure is recorded on the Pre-Post Trip Analog i Recorder and a Strip Chart Recorder.

k) Primary System Temperature - Primary system temperature is not a direct reactor trip. However, primary system temperature is recorded on both I the Pre-Post Trip Analog Recorder and a Strip Chart Recorder.

1) Pressurizer Level - Pressurizer level is not a reactor trip. However,

! pressurizer level is recorded on the Pre-Post Trip Analog Recorder and a Strip Chart Recorder. In addition, low pressurizer level is recorded on the l Sequence of Events Recorder.

m) Reactor Coolant Pump Status - Reactor coolant pump underspeed is a

! reactor trip and is recorded on the Sequence of Events Recorder, n) Primary System Flow - Low primary system flow which is a reactor trip is recorded on the Sequence of Events Recorder.

o) Safety injection; Flow, Pump / Valve Status - Safety injection pump start is e

recorded on the Sequence of Events Recorder. The valves are pre-

positioned to give a specified flow rate. When the pumps come up to speed, required flow is obtained through pre-positioning of the safety injector valves.

i p) MSIV Position - MSIV closure is recorded r,n the Sequence of Events Recorder, q) Steam Generator Pressure - Steam generate,r pressure is a trip parameter and is recorded on the Sequence of Events Recorder when a steam j generator pressure trip is initiated. In addition, steam generator pressure

is recorded on the Pre-Post Trip Analag Recorder and a Strip Chart Recorder.

r) Steam Generator Level - Steam generator level is a trip parameter and is recorded on the Sequence of Events Recorder when a steam generator level trip is initiated. In addition, steam generator level is recorded on the Pre-Post Trip Analog Recorder and a Strip Chart Recorder.

s) Feedwater Flow - Feedwater flow is not a trip parameter. However, feedwater flow is recorded on the Pre-Post Trip Analog Recorder and a Strip Chart Recorder.

i i

t) Steam Flow - Steam flow is not a trip parameter. However, steam flow is recorded on the Pre-Post Trip Analog Recorder and a Strip Chart Recorder. .

u) Auxiliary Feedwater System; Flow, Pump / Valve Status - Auxiliary feedwater pump start and valve opening are recorded on the Sequence of Events Recorder.

v) AC and DC System Status (Bus Voltage) - Low AC or DC voltage (undervoltage) events are recorded on the Sequence of Events Recorder.

~

w) Diesel Generator Status (Start /Stop, On/Off) - Diesel generator start and failure events are recorded on the Sequence of Events Recorder.

x) PORY Position - PORVs open coincident with a reactor trip on high pressure. No direct position indication is available, however, PORV position can be inferred from the quench tank high level, pressure or temperature alarms, tailpipe high temperature alarm, or acoustic monitoring alarm, all of which are recorded on the Sequence of Events Recorder.

Time History Recorders Performance Characteristics The new process computer for Millstone 2, which is scheduled to be operational in 1987, is being procured to have the capability to record parameter values at the following sample intervals.

a) For the interval 15 minutes pre-trip to 1 minute pre-trip the sample interval will be 15 seconds.

b) For the period I minute pre-trip to 1 minute post-trip, the sample interval will be 5 seconds.

c) For the interval 1 minute post-trip to 15 minutes post-trip, the sample interval will be 15 seconds.

Data Retention Capability Pre-Post Trip Analog printouts and Strip Chart Recorder information is retained for the life of the plant.

Millstone 2 '

Desirable PWR Parameters for Post-Trip Review (circled parameters are not recorded)

SOE Time History Recorder Parameter / Sional Recorder Reactor Trip

@ Safety Injection (1)

Containment Isolation Turbine Trip (1)

Control Rod Position x Meutron Flux, Power (1)

Containment Pressure Containment Radiation t.

Containment Sump Level .

x Primary System Presti.'e (1)@ Primary System Temperature (1) x x (1) x Pressurizer Level Reactor Coolant Pump Status (1)

Primary System Flow (1) @ Safety Inj.; Flow, Pump /Yalve Status MSIY Position

@ Steam Generator Pressure x

x Steam Generator Level (1) x Feedwater Flow (1) x Steam Flow (1) x 3

Auxiliary Feedwater System; Flow.

Pump /Value Status AC and DC System Status (Bus Voltage)

Diesel Generator Status (Start /Stop, 8x x

On/Off)

PORY Position (1): Trip parameters

! (2): Parameter may be monitored by either an SOE or time history recorder.

(3): Acceptable recorder options are: (a,) system' flow recorded on an SOE l

recorder, (b) system flow recorded on a time history recorder, or (c) equipment status recorded on an SOE recorder.

TABLE 2 f

l 1