ML20215J985
| ML20215J985 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 10/20/1986 |
| From: | Bailey J GEORGIA POWER CO. |
| To: | Youngblood B Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.F.1, TASK-TM GN-1127, NUDOCS 8610270289 | |
| Download: ML20215J985 (7) | |
Text
E 4
Georgio Power Company Post Offic2 Box 282 Waynesbora Georgia 30830 Telephone 404 554-9961 404 7244114 Southern Company Services, Inc.
Post Office Box 2625
-Birmingham, Alabama 35202 Telephone 205 8704011 Vgtie PMect October 20, 1986 Director of Nuclear Reactor Regulation File:
X7BC35 Attention:
Mr. B. J. Youngblood Log:
GN-1127 PWR Project Directorate #4 Division of PWR Licensing A U. S. Nuclear Regulatory Commission Washington, D.C.
20555 NRC DOCKET NUMBERS 50-424 AND 50-425 CONSTRUCTION PERMIT NUMBERS CPPR-108 AND CPPR-109 V0GTLE ELECTRIC GENERATING PIANT - UNITS 1 AND 2 SER CONFIRMATORY ITEM 42: NUREG-0737, ITEM II.F.1
Dear Mr. Denton:
Attached for your staff's review is CPC's re.$ponse to II.F.1, Nobel Gas Monitor and Sampling of Plant Effluents.
If your staff requires any additional information, please do not hesitate to contact me.
Since rely,
.h.
J. A. Bailey Project Licensing Manager JAB /sm Attachment xc R. E. Conway NRC Regional Administrator R. A. Thomas NRC Resident Inspector J. E. Joiner, Esquire D. Feig B. W. Churchill, Esquire R. A. McManus M. A. Miller (2)
L. T. Gucwa B. Jones, Esquire Vogtle Project File G. Bockhold, Jr.
0804V
$50$
00 o
a
r Item II.F.1, Attachment 1.
" Noble Gas Efflu2nt Monitor" and " Sampling and Analysis for Plant Effluents FSAR Section 11.5 provides detailed descriptions of the effluent monitors installed at VEGP.
The following paragraphs provide the additional information required by NUREG-0737,Section II.F.1, Attachments 1 and 2, for the potential accident release pathways.
A.
Plant Vent Monitor The plant vent collects discharges from the Containment Purge System, the Auxiliary Buf1 ding HVAC System, the Fuel Handling Building HVAC System, and the electrical penetration filter and exhaust system.
FSAR ' Figure 9.4.9-2 includes the piping and instrumentation diagram for the plant vent monitors, RE-12444A, B and C.
These monitors are located in the Equipment Building, Level 1,
at elevation 220 feet (FSAR Figure 12.3.1-3, Sheet 16).
There are two Seismic Category 1 isokinetic samplers provided for each plant vent.
One is for sampling during normal operation when the flow through the plant vent is approximately 150,000 cfm (90,000 cfm for Unit 2) and the other is for sampling during post-accident conditions (with offsite power unavailable) when the flow through the plant vent is reduced to approximately 9,000 cfm (3,200) cfm for Unit 2).
The isokinetic probes are installed in accordance with ANSI N13.1-1969 and have the capability of maintaining isokinetic flow conditions with variations of vent flow velocity of 120 percent.
Switching from the i
normal operation isokinetic probe to the post-accident isokinetic probe is provided automatically on low plant vent flow.
t The valves employed in the isokinetic flow switching manifold are Seismic Category 2, however, the valves and sample tubing are supported by l
Seismic Category _1 supports.
Each plant vent has a Seismic Category l
1 flow transmitter, that is powered by a non-Class IE battery backed power source.
The flow transmitter is used to measure the total vent flow rate and can be read out in the Control Room and TSC via the emergency response facility computer.
The vent flow rate reading allows the operator to compute the effluent radiation level in units of pCf/sec (Xe-133).
I The sample from the isokinetic probe is routed to the shielded cartridge assembly.
This assembly provides for passive collection of both i
particulate and iodine samples on filters.
Another cartridge assembly l
1s on standby and may be valved into the system.
This allows sampling to continue while the other cartridge assembly is removed for analysis.
i In a high range sample condition, high activity will be accumulated
)
on the filters, so the filters are surrounded with a two-inch lead shield for personnel protection and activity transportation.
The onsite I
laboratory is capable of identifying and quantifying isotopes from l
the iodine and particulate filters using a computer enhanced germanium gama spectroscopy system.
Samples with more than 100 pCi of activity will be analyzed offsite or in some other nonroutine manner.
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Thg shielding design basis is the same as given in Table II.F.1-2 (i.e.,
10' pC1/cc of gaseous radioicdine and particulates deposit 1d on the filters, 30 minutes sampling time, average gamma energy of 0.5 Mev).
The filters have a greater than 90 percent effective adsorption for all forms of gaseous iodine and a greater than 90 percent effective retention for 0.3 micron diameter particles.
The filters are designed with materials which minimize the adsorption of noble gases.
The shielded cartridge assembly is designed to require minimum maintenance.
The dimensional envelope of the assembly is approximately 9 in. H x 10 in. W x 7.5 in. D.
It weighs approximately 150 pounds.
After passing through the shielded cartridge assembly, the sample is routed to the gas detector assembly.
This assembly contains threq radioactive gas detectors which cover a range of 10-6 pCf/cc to 109 pCi/cc (Xe-133).
The range capacity of the low-range and intermediate-range detectors provide for sufficient overlap to ensure continuity of linearity.
A software modification is being processed to provide sufficient overlap between the intennediate and high range detectors to ensure continuity of linearity.
This software modification is scheduled to be completed by November 1,1986. The low-range detector utilizes a beta scintillator, whereas the mid-range and high-range detectors are solid-state GM tubes and are specially selected for this application.
As the lower range detectors reach their individual top-of-scale setpoints, they are programmed to be turned off.
After activity levels return to within their ranges, they are programmed to be turned on.
The assembly also contains the necessary pump, flow control valves and flowmeter.
The gas detector assembly is Seismic Category 1 and is powered by a non-Class IE power source that is automatically loaded onto,the diesel generator on loss-of-offsite power.
The detectors used in the wide range effluent monitor have a primary laboratory calibration report which documents the initial
" type" calibration which was performed.
The initial calibration was performed with the use of National Bureau Standards (NBS) traceable gaseous and solid sources which establish both. the energy and linearity response of the detectors.
Gaseous standards were introduced into the sample chamber to establish the sensitivity of the 3 detectors.
They were subjected to Xe-133 at approximate concentrations of 6E-4, 2E-3, 2,
53, and 85 pCf/cc.
These concentrations were chosen so as to provide 2 points per detector.
The energy response check of the G-M tubes was performed using Co-60, Cs-137. Ba-133, Co-57 and Cd-109 point sources in a fixed geometry.
The calibration report for the beta scintillation detector provides energy response for Ar-41, Kr-85, Xe-133, and Xe-135.
j Subsequently, the detectors were calibrated against two (2) secondary sealed standards with fixed geometrical configurations.
These secondary j
calibration standards provide for the periodic on-site recalibration to ensure the response of each detector is in agreement with the response i
as determined in the original " type" calibration.
The frequency of the field calibration for the wide range effluent monitor is every refueling.
Each detector has a solenoid-actuated check source to verify operability.
l Th2 plant vent monitor data processing module (DPM) receives input from the plant vent monitor.
The DPM provides digital communication with the communication console in the Control Room.
The DPM stores the average radiation level for the following intervals:
- 24 most recent 10-minute periods
- 24 most recent 1-hour periods
- 30 most recent 1-day periods The plant vent monitor DPM is Seismic Cate a non-Class 1E battery backed power source. gory 1 and is powered from The infomation from the DPM is displayed in the Control Room via the communications console on a CRT and hard copy printer on demand.
The communications console is powered from a non-Class IE source and may be manually loaded onto the diesel generator if power is lost.
The communications console is linked to the emergency response facility computer to provide the radiation infomation into the TSC.
The communications console also provides historical data to the minicomputer for the process and effluent monitoring system.
The following radiation and process flow data is maintained on disc and is available for display on demand:
- 10 minute average for 7 days
- I hour averages for 30 days 1
- daily averages for 30 days B.
Condenser Air Ejector and Steam Packino Exhauster Monitor The gases released from the condenser vacuum exhaust, steam jet air ejectors, and steam packing exhauster are monitored by the condenser air ejector and steam packing exhauster monitor, RE-12839A 8 and C.
FSAR Figure 9.4.4-1, Sheet 3, includes the piping and instrumentation diagram for this monitor.
The monitor is located in the Turbine Building i
Level 3 at elevation 270 feet (FSAR Figure 12.3.1-3), Sheet 32).
1 The condenser air ejector and steam packing exhauster monitor consists of an isokinetic probe, passive particulate and iodine filters, sample l
conditioner, and radiogas detector.
The isokinetic probe is installed in accordance with ANSI N13.1-1969.
Because the sample temperature may be as high as 200F and the relative humidity may be at 100 percent, and as such, to condition the sample stream to be compatible with the radiogas detector, a chiller and a moisture separator are provided upstream of the radi a range or 5 x 10 ggas detector. 5 The radiogas monitor assembly covers pC1/cc to 10 pCf/cc (Xe-133) and contains three detectors.
The range capacity of the low-range and intemediate-range l
detectors provide for sufficient overlap to ensure continuity of linearity.
A software modification is being processed to provide sufficient overlap between the intemediate and high range detectors to ensure continuity of linearity.
This software modification is scheduled to be completed by November 1,1986.
The low-range detector utilizes a beta scintillator, whereas the mid-range and high-range detectors are solid-state GM tubes.
The monitor skid also contains the necessary pump, flow control valves and flowmeter. The vent has a flow transmitter that measures the total vent flow rate.
The condenser air ejector and steam packing exhauster DPM receives input from the monitor and flow transmitter.
The monitor, transmitter and DPM are Seismic Category 2 and are powered by a non-Class 1E source that can be manually loaded onto the diesel generator.
The detectors used in the wide range effluent monitor have a primary laboratory calibration report which documents the initial
" type" calibration which was performed.
The initial calibration was performed with the use of NBS traceable gaseous and solid sources which establish both the energy and linearity response of the detectors.
Gaseous standards were introduced into the sample chamber to establish the sensitivity of the 3 detectors.
They were subjected to Xe-133 at approximate concentrations of 6E-4, 2E-3, 2,
53, and 85 pC1/cc.
These concentrations were chosen so as to provide 2 points per detector.
The energy response check of the G-M tubes was performed using Co-60, Cs-137, Ba-133, Co-57 and Cd-109 point sources in a fixed geometry.
The calibration report for the beta scintillation detector provides energy response for Ar-41, Kr-85, Xe-133, and Xe-135.
Subsequently, the detectors were calibrated against two (2) secondary sealed standards with fixed geometrical configurations.
These secondary calibration standards provide for the periodic on-site recalibration to ensure the response of each detector is in agreement with the response as detemined in the original " type" calibration.
The frequency of the field calibration for the wide range effluent monitor is every refueling.
Each detector has a solenoid-actuated check source to verify operability.
The discussion under the plant vent section on the communication console and historical data storage is also applicable to the condenser air ejector and steam packing exhauster monitor.
C.
Main Steam Line Monitor A radiation monitor is mounted in close proximity to each steam line in the main steam isolation valve areas on Level 1 (FSAR Figure 12.3.1-3, Sheets 10, 19 and 22).
These monitors measure direct dose rate from the main steam line to quantify effluent releases from the steam generator safety valves, atmospheric dump valves and the auxiliary feedwater steam turbine exhaust vent.
FSAR Figure 10.3.2-1 Sheet
?, includes the piping and instrumentation diagram for the main steam line monitors (RE-13119, 13120, 13121 and 13122).
The main steam lina monitor has a range of 10-1 RCf/cc to 103 pCi/cc.
l In order to obtain concentrations of 10-1 to 10J pCi/cc of (Xe-133) j in the main steam line, a large primary to secondary leak must be present coincident with a large amount of fuel failure.
Based on the ratios of isotopic composition in the fuel and steam generator reduction l
factors, relative main steam line concentrations can be detemined.
The main steam Ifne detectors are shielded by 6 to 8 inches of lead.
l This lead acts as a collimator so the detector looks at a known main steam line geometry.
The lead reduces the potential background from the main steam Ifne piping.
l j
The main steam line DPMs receive input from the main st:am lin2 monitors and transmit data to the safety-related display console in the Control Room.
The monitors and DPMs are Seismic Category 1 and Class 1E.
The safety-related display console transmits data to the communication console as shown in FSAR Figure 11.5.2-1.
The detectors used in the main steam line monitor have a primary laboratory calibration report which documents the initial
" type" calibration which was performed.
The initial calibration was perfomed with the use of NBS traceable sources which establish both the energy and linearity response of the detectors.
Solid standards were positioned at various locations of a mocked-up main steam line to duplicate the cone-shaped geometry the detector views.
The sources which were used were Co-60, Cs-137 and Ba-133 for the energy and linearity response.
The readings were integrated over the length of the cone to detemine the overall response for the various isotopes.
Subsequently, two (2) secondary sealed sources with fixed geometrical configurations were related to the. inital " type" calibration.
These secondary calibration standards provide for the periodic on-site recalibration to ensure the response of each detector as in agreement with the response as determined in the original calibration.
The frequency of the field calibration for the main steam line monitor is every refueling.
Each detector has a solenoid-actuated check source to verify operability.
D.
Steam Generator Liquid Monitor In case of a steam generator blowdown line break the release is quantified by the reading from the steam generator liquid monitor.
This monitor consi a range of 4 x 10 gts of an of{-line gamma scintillation detector with
' to 4 x 10-pCi/cc and is located in the Auxiliary Building Level B at elevation 170 feet-6 inches (FSAR Figure 12.3.1-3, Sheet 6).
FSAR Figure 10.4.8-1, Sheet 1,
includes the piping and instrumentation diagram for the steam generator liquid monitor, RE-019.
As discussed in response to NRC question 460.08, the steam generator blowdown line will be automatically isolated after the break is detected, so the release will be limited to a short duration.
The steam generator liquid monitor and its associated DPM are Seismic Category 2 and powered by a non-Class 1E source.
If the steam generator liquid monitor is not available, a sample of the steam generator may also be taken to obtain a more quantitative analysis of the activity released out the break in the steam generator blowdown line.
The detectors used in the Steam Generator Liquid monitor have a primary laboratory calibration report which documents the initial
" type" calibration which was performed.
The initial calibration was performed with the use of NBS traceable liquid sources which establish both the j
energy and linearity response of the detectors.
The calibration standards used in the initial " type" calibration were Cd-109, Co-57 Cr-51 Cs-137, Mn-54, and Co-60 in the Marinell configuration of the monitor skid. - - - -
4e Subsequently, two (2) seccndary sealed standards with fixed geometrical configurations were relattd to the initial " type" calibration.
These secondary calibration standards provide for the periodic on-site recalibration to ensure the response of each detector is in agreement with the response as detemined in the original " type" calibration.
The frequency of the field calibration for the Steam Generator Liquid monitor is every refueling.
Each detector has a solenoid-actuated check source to verify operability.
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