ML20028G407
| ML20028G407 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek, Callaway, 05000000 |
| Issue date: | 02/04/1983 |
| From: | Petrick N STANDARDIZED NUCLEAR UNIT POWER PLANT SYSTEM |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.B.3, TASK-TM 83-0007, 83-7, NUDOCS 8302090308 | |
| Download: ML20028G407 (7) | |
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SNUPPS Stenderdiaod Nucieer Unit i
Power Plant System 5 Choke Cherry Road Nicholas A. Petrick Rockville, Marytend 20050 Executive Director (301) 8694010 February 4,1983 SLNRC 83 0007 FILE: 0278 SUBJ:
NUREG-0737 II.B.3, Post Accident Sampling Capability Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Comission Washington, D. C. 20555 Docket Nos. STN 50-482 and STN 50-483
Dear Mr. Denton:
The enclosure provides additional information regarding the post-accident sampling system design for the SNUPPS facilities. The information is-provided to resolve, in part, License Condition 20 for Callaway Unit No.1 and License Condition B.17 for Wolf Creek Generating Station Unit No.1 The enclosed data supplement the information contained in Section 18.2.3 of the SNUPPS FSAR. Additional information describing the administrative controls and procedures to be implemented for post-accident sampling at the l
SNUPPS facilities will be provided later in accordance with the provisions l
of the license conditions.
Very(truly yours, RMMQ Nicholas A. Petrick filF/nid j
enclosure cc:
D. T. McPhee KCPL J. H. Neisler USNRC/ CAL l
G. L. Koester KGE T. E. Vandel USNRC/WC l
D. F. Schnell UE 8302090308 830204 PDR ADOCK 05000482 A
Enclosure to SLNRC 83- 0007 SNUPPS POST ACCIDEtiT SAMPLING SYSTEM Responses to License Condition Items for Post Accident Sampling System (PASS) Capability:
ITEM #1:
Demonstrate compliance with all requirements of NUREG-0737. II.B.3 for sampling, chemical, and radiological analysis capability, under accident conditions.
SNUPPS Desiger The SNUPPS post accident sampling system (PASS) is an online automated system designed to provide immediate detailed analysis of liquid and gas samples. The system is capable of analyzing for radionuclides and various chemical species in reactor coolant, containment atmosphere and containment sump samples taken during normal and/or accident conditions.
Sample collection and analysis is possible immediately upon the decision to take a sample. Valving and sample flow control is performed by computer from a control panel located in the health physics area. This area is considered a vital area for which continuous occupancy is assured during accidents as described in Section 18.2.2 of the FSAR.
The PASS also can be used to take grab samples by automatic or remote manual methods and handle them by semi-remote manual methods in the event of failure of the on-line system. Redundant sample points are provided with sample isolation valves (i.e. containment isolation valves) powered via class IE redundant circuits to assure sample availability.
The on-line sampling capability includes analysis for:
Liquid samples (reactor coolant and containment sump):
-3 Gross radioactivity 10 Ci/mi to 10 Ci/mi Gamma spectrum isotopic analysis Boron content 50-6500 ppm Chloride content 0.1-20 ppm Dissolved hydrogen 0-3000 cc/kg Dissolved oxygen 0-20 ppm ph 0-14 Conductivit 0-1000judhos Gas sample (containment atmosphere):
Hydrogen content (see below) l 0xygen content 0-39wt%
l Gross radioactivity 10 pCi/ml - 10 pCi/ml
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Gamma spectrum isotopic analysis 1 of 6
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Gaseous hydrogen is monitored by dedicated, redundant Class IE powered hydrogen analyzers with a range of 0-10 volume %.
The hydrogen analyzers are provided with redundant nefety grade containment isolation valves which are powered by Class IE power supplies.
Before a radiological or chemical analyses is performed the sample lines are purged to staure representative sampling. During normal operation the purged liquid samples are returned to the waste holdup tank fcr reprocessing before being returned to the reactor coolant inventory.
During accident conditions the liquid samples are returned to the reactor coolant drain tan'k located in the containment. Containment atmosphere samples are returned to the containment during-normal and accident conditions.
ITEM.f2:
Provide sufficient shielding to meet the requirements GDC 19, assuming Regulatory Guide 1.4 source terms.
SNUPPS Design:
The SNUPPS PASS is controlled from a panel located in the health physics area which is below grade elevation in the control building. The health physics area is considered a vital area for which continuous occupancy is assured during accidents and has a dose rate less than 0.015 R/hr, as described in Section 18.2.2 and figure 18.2-7 of the TSAR.
Only in the event of failure of the online system is the operator required to retrieve grab samples from the sampling cabinet for offline analysis. The grab sample system is designed so that operator doses will be as low as reasonably achievable and within limits specified in GDC 19.
The provis'ons to minimize personnel exposure while retrieving grab samples are as follows:
1.
The sample line sizes and component internal volumes were minimized to reduce the amount of radioactivity at the sample panel location.
2.
The sample can be drawn automatically by operator selection at the remote panel, thereby minimizing operator time in the vicinity of the sample.
3.
The sample lines within the sample panel are purged automatically af ter sampling with demineralized water, or instrument air as appropriate, including the connections to the cask and those on the cask itself.
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4.
Diluted or undiluted samples can be obtained.
5.
The ceska can be remotely disconnteted from the panel.
6.
The sample panel is shielded with lead.
7.
The undiluted sample casks ere heavily shielded and the transport cart is electrically powered with an 8 ft control cable to maximize distance between the source and the operator.
Item f3:
Commit to meet the samnling asd analysis requirement of Regulatory Guide 1.97, Revision 2.
SNUPPS Design:
Specific sampling capabilities of the SNUPPS PASS are given in response to Item fl. SNUPPS capcbilities acet or exceed the accident sampling capabilities recommended in Reg. Guide 1.97, Rev. 2 as described in Appendix 7A of the FSAR. The SNUPPS PASS is designed to fanction accurately and reliably in neraal and accident environments. The radiation detection and analysis system, inline chemical analysis components, data aquisition hardware and software, and sample delivery systems are components that have been carefully selected from suppliers of products of proven capebility and reliability. Responses to Items #4 and f5 below address the functioning of the system during abnormal occurrences.
Item f4:
Verify that all electrically powered components associated with post accident sampling are capable of being supplied with power and operated within 30 minutes of an accident in which there is core degradation, assuming a loss of offsite power.
SNUPPS Design:
The PASS panel is nornally powered from non Class lE offs'te power, but is provided with the capability to be ranually transferred to a Class l
IE, diesel backed source.
In the event of a safety injection actuation
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signal, concurrent with a loss of offsite power, the operator will be required to reset the safety injection actuation signal in the control rpon before manually loading the PASS onto the Class IE bus at the MCC.
In the event of safety injection only, without loss of offsite power, power to the PASS would be uninterupted. This design provides the l
capability to return power to PASS within 30 minutes of a loss of the normal power supply.
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s The containment isolation valves associated with the PASS are redundant for all sample points and are supplied with diverse Class IE power supplies. As such, the single failure of any one safety grade power supply will not preclude the PASS from obtaining liquid or gaseous samples. The return lines to the containment are also provided with redundant safety grade isolation valves powered by diverse, Class IE power.
ITEM #5:
Verify that valves which are not accessible for repair after an accident are environmentally qualified for the conditions in which they must operate.
SNUPPS Design:
The containment isolation valves, both inside and outside the containment are Class IE and are qualified for all accident conditions.
All valves within the sample panel were selected so that they would be able to withstand the environmental conditions both during normal operation and accidents. Use of materials susceptible to radiation was avoided. All valves were selected for high reliability and low maintenance requirements.
ITEM #6:
Provide a procedure for relating radionuclide gaseous and ionic species to estimate core damage.
SNUPPS Design:
Radionuclide cualysis for containment atmosphere, containment sump and reactor coolant is performed by an inline intrinsic germanium detector and associated multichannel analyzer. A rotating tungsten-alloy collimator is used to select the proper sampling geometry for the wide range of activities possible. Isotope identification and quantification are performed automatically. The concentration of a particular radioactive species is used to evaluate fuel performance during steady state operations and transients and to characterize fuel damage during accident conditions. Activated corrosion products, noble gases, halogens, and cesiums which are normally present in the RCS, originste from anticipated events such as crud bursts, iodine spikes or fuel defects. They are characterized by relatively low level radioactivity concentrations. Major fuel degradation is indicated by the presence of significantly higher concentrations of these species and the presence of l
refractory isotopes or fuel fines. The concentrations of each species l
is related to the amount of fuel degradation cerswi2 ring dilution l
volumes and decay times. Specific procedures and normal operating experience will be used to develop detailed interpretation of radionuclide analysis of the samples.
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ITEM #7:
State the design or operational provisions to prevent high pressure carrier gas from enterinE the reactor coolant system from online gas analysis equipment, if it is used.
SNUPPS Design:
High pressure carrier gases are not used in the SNUPPS design.
ITEM #8-Provide a method for verifying that reactor coolant dissolved oxygen is at less than 0.1 ppm if reactor coolant chlorides are determined to be greater than 0.15 ppm.
SNUPPS Design:
The ranges specified for the online equipment are 0.1-20 ppm for the chloride analyzer and 0-20 ppm for the oxygen analyzer. Therefore the requirement can be met.
ITEM #9:
Provide information on (a) testing frequency and type of testing to ensure long term operability of the post accident sampling system and (b) operator training requirements for post accident sampling.
SNUPPS fesign:
a.
The SNUPPS PASS was designed for use during both normal and post accident conditions. The long term operability of the PASS is assured by performing system operational checks and system functional checks intermittently.
An operational check shall verify the ability of the PASS to analyze routine samples.
A functional check shall verify the ability of the PASS to analyze known sample concentrations.
b.
The PASS vendor will provide initial training of plant personnel to indoctrinate them in the design and operation of the PASS.
This training will cover as a minimum.
- System function, requirement, and layout
- Operating procedures, control, and alarms
- Maintenance 5 of 6
The utility will provide training of plant personnel to instruct them in the design and operation of the PASS. This training will cover as a minimum:
- System function, requirement, and layout
- Operating procedures, control, and alarma
- Maintenance All personnel using the PASS will be qualified by the utility in the task being performed. Requelification will occur every two years.
Identif'ication of Online Instrumentation The ? ASS components are designed to function under the expected environmental conditions during an accident. The following is a list of the specific components planned for use along with model number, but equivalent equipment may be used in the future.
COMPONENT MAKE AND MODEL #
Radioisotopic High Purity Germanium Detector Canberra High voltage supply Canberra 3105 Preamps Canberra 2001 Low LN alarm sens r Canberra 1786 2
Log Ratemeter Tennelec TC595 Analyzer Canberra Jupiter Series 80 MCA Series 80 Chassis 8683A 3 amplifiers /ADC 8623 PHA/LTC Chemical Analyzers Dissolved oxygen Beckman 7002 Dissolved hydrogen Teledyne Basings 225 Chloride Orion Boron SAI ph Beckman 960B Conductivity Beckman RA6X8 l
Oxygen Beckman 7002 The safety grade containnent atmosphere hydrogen analyzers belong to a different system. They are Consip-Delphi K III's.
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