ML20050C178
| ML20050C178 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 03/15/1982 |
| From: | Goddard R NRC OFFICE OF THE EXECUTIVE LEGAL DIRECTOR (OELD) |
| To: | Foster R, Kelley J, Morris P Atomic Safety and Licensing Board Panel |
| References | |
| ISSUANCES-SP, NUDOCS 8204080245 | |
| Download: ML20050C178 (2) | |
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UNITED STATES D
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M 4m E WASHINGTON, D. C. 20555 March 15, 1982 d{
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6 Janes'L. Kelley, Chairman Dr. Peter A. florris
/ co Administrative Judge Administratiye Judge Atomic Safety and Licensing Atomic Safety and Licensing Board Panel Board Panel U.S. Nuclear Regulatory Commission U.S. fiuclear Regulatory Commission Washington, D.C. 20555 Washington, D.C. 20555 Dr. Richard Foster
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Administrative Judge P.O. Box 4263 D
Sunriver, Oregon 97701 NEC(:j APR y
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In the Matter of
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Commonwealth Edison Company (Quad Cities Station, Units 1 and 2) 1 O/
Docket Nos. 50-254-SP & 50-265-SP 4
s (Spent Fuel Pool Modification)
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Dear Administrative Judges:
The purpose of this letter is to confirm in writing the positions taken by the Nuclear Regulatory Commission Staff Counsel in the captioned proced-ing during the telephone conference call with the Board and parties which took place on Wednesday, March 10, 1982. The following numbered paragraphs incorporate the Staff's response ta questions propounded in the Licensing Board's Order scheduling this ennference call:
(1) The answer is appropriately furnished by ".pplicant Commer. wealth Edison Company.
(2) The Staff estimates that the Environmental Inpact Appraisal and Safety Evaluation for the reracking can be completed and served approxmiately April 9,1982.
(3) Discovery. The Staff has no pending discovery actions and anticipates no further discovery in this proceeding, in the event that Intervenors accede to withdraw the structural engineering contention dealing with the adequacy of the racks.
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-to withstand a seismic event.
In the event this contention is
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not withdrawn, the Staff would request approximately onc week's 1
time from receipt of notification of the intentions of the
-Intervenors with regard to this contention to file intensive b
interrogatories upon the Intervenors to ascertain their basis
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for this contention.
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(4) The Staff is enclosing affidavits of fir. Roby Bevan and two technical reviewers with regard to Contentions 1 through 4, which Intervenors have requested be withdrawn. fir. Bevan will subsequently prepare an affidavit to support the intervenors request to withdraw Contention 7(a). Contention 7(b)and7(c) were the subject of a motion to withdraw by Intervenors, solely as a result of internal discussions held by their groups, and the Staff has not taken a position or furnished any technical information to the groups with regard to these two subparts of Contention 7.
(5) The Staff does not anticipate filing motions for sumary disposition in this proceeding. However, further negotiations are being held with regard to the withdrawal of remaining contentions in the proceeding.
(6) The answer is appropriately furnished by Applicant Comonwealth Edison Company.
(7) The Staff took the position that a hearing comencing dur' ;
the week of liay 10, 1982, would adequately accomodate tt remaining schedule for the case.
It is anticipated that uch a hearing would take no more than three days to complete, without allowing time for extensive limited appearances or litigation of Admitted Contention 9 (structural adequacy of the new racks).
The Staff anticipates that Mr. Bevan's affidavit on Contention 7(a) will be fomarded to the Board and parties not later than liarch 19, 1982.
Sincerely, Richard J. Goddard Counsel for NRC Staff
Enclosure:
As stated cc: Atomic Safety and Licensing Board Panel Atomic Safety and Licensing Appeal Board Panel Citizens for Safe Energy Quad-Cities Alliance for Safe Energy and Survival Older Americans for Elderly Riohts Q'/
Robert G. Fitzgibbons, Jr., Esq.
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3 I, Roby Bevan, being duly sworn, state that I am an employee of the U.S. Nuclear Regulatory Commission (NRC).
My present position is Operating Reactors Project Manager, Operating Reactors Branch #2,
- Division of Licensing within the Office of Nuclear Reactor Regulation.
The purpose of my affidavit is to respond to a contention having to do with corrosion of fuel rod cladding due to increased fuel storage
- and resultant increased temperatures in the pools. An exact statement of
-the contention and my response to that contention follows.
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Contention 1 Intervenors contend that the additional spent fuel assemblies which will be stored in the proposed high density spent fuel storage racks will increase the temperature of the spent fuel pool water and cause the cladding of the rods to corrode, thereby endangering the public health and safety.
Response to Contention 1 The temperature of the spent fuel pool water is maintained at about 95-100 F, except when newly discharged spent fuel is in the pool.
During refueling the temperature can rise to 125-150 F due to increased decay heat from the newly discharged fuel. Within a week or two the decay heat rate is diminished such that the pool water temperature is again easily kept in the 95-100 F range.
Thase temperatures stated above are not maintained for reasons having to do with corrosion of fuel cladding, but are primarily for the canfort and safety of personnel working in the area. The temperatures indicated are easily held using only part of the presently installed spent fuel pool cooling capability. With the proposed increased spent fuel storage capacity, the heat load on the pool cooling capability will increase gradually over the years.
Should the pool eventually be filled to capacity (the limiting case),
the pool cooling capability that is presently installed will still be adequate to maintain pool water temperatures that are consistent with personnel comfort and safety.
It is not expected that the pool temperature conditions will change significantly from those of the past as a result of the increased storage capability. Therefore, danger to the public health and b
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safety resulting frca increared corrosion of fuel cladding as a result of increased pool water. temperature is not a valid concern.
The above statements and opinions are true and correct to the best of my personal knowledge and belief.
d e-s Roby B. Bevan, Jr.
Subscribed and sworn to before me th i s il i s day of November, 1981.
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UNITED STATES OF AMERICA NUCLEAR REGULATORY C0tCISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of
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Docket Nos. 50-254 COMMONWEALTH EDISON COMPANY
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50-265
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(Spent Fuel Pool Modifications)
(Quad Cities Station, Units 1 and 2) )
TESTIMONY OF CHANDU P, PATEL ON CONTENTION 3.a I, Chandu P. Patel, do state as follows:
I am employed by the United States Nuclear Regulatory Commission, as a nuclear engineer in the Division of Systems Integration, Effluent Treatment Systems Branch.
This testimony addresses Contention 3.a concerning the matter of increasing
- the capacity of the ventilation systen., which is stated as follows:
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"Intervenors contend that the increased amounts of irradiated fuel in the proposed spent fuel pools will increase radiological releases from the pools and occupational exposures in the pools area.
In light of this, the present radiation monitoring system is inade-quate to provide a reasonable assurance of public health and safety.
Specifically, reanalysis of the present system should be required, and should consider:
a.
increasing the capacity of the ventilation' system "
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2 It should be noted that the spent fuel storage capcity will be increased by changing the design of spent fuel storage racks from present design to a high density rack design.
Thus, the licensee will be able to store more spent fuel assemblies in the same pool. Additional capacity will accommo-date the spent fuel which has been out of the reactor for a longer period of time, e.g., four to five years.
With respect to releases of gaseous materials to the atmosphere, the only radioactive gas of significance which could be attributable to storing additional fuel assemblies for longer periods of time would be the noble gas radionuclide Krypton-85. Other short lived radionuclides are not present in the aged fuel.
Due to the reduced specific activity, low radiological heating and the physical characteristics of spent fuel, there will not be a significant release of fission products, including Krypton-85, from the stored fuel after it has decayed for one year in the spent fuel pool. Thus, the amount of Krypton-85 released from the aged fuel at the spent fuel pool temperature will be neg-ligibly small.
Based on above analysis, I conclude that there is no need to increase the capacity of the ventilation system due to the increased storage of spent fuel assembli,es.
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The above statements and opinions are true and correct to the best of my personal knowledge and belief.
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m.lst f-fc h Chandu P. Patel, Nuclear Engineer Effluent Treatment Systems Branch Division of Syster. Integration, NRR Subscribed and sworn to before me thisd'hk day of November, 1981.
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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSIfiG BOARD In the Matter of Docket Nos.
50-254 COMMONWEALTH EDIS0N COMPANY 50-265 (Spent Fuel Pool Modifications)
(Quad Cities Station, Units 1 and 2)
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TESTIMONY OF SEYMOUR BLOCK ON CONTENTION 3.b I, Seymour Block, do state as follows:
I am employed by the United States Nuclear Regulatory Commission,'as a Senior Health Physicist in the Division of Systems Integration, Radiological Assessment Branch.
This testimony addresses Contention 3.b concerning the matter of spent fuel pool instr.umentation, which is stated as follows:
3.
"Intervenors contend that the increased amounts of. irradiated fuel in the proposed spent fuel pools will increase radiological. releases from the pools and occupational exposures in the pool's area.
In light of this, the present radiation monitoring system is inadequate
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to provide a reasonable assurance of public health and safety.
Speci-fically, reanalysis of the present system should be required, and sho0ld consider:
b.
increasing the range, sensitivity and number of area monitors, including GM monitors, and monitors of the pool water itself.-
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Response
(3)(b) The increment in dose rate resulting-from the proposed increase in stored fuel assemblies will be quite small compared to the dose rate from the present spent fuel pool capacity. The spent fuel assemblies themselves contribute a negligible dose rate to the pool area because of the depth of water shielding in the pool. Calculations made for the dose equivalent rate (mrem /hr) above the surface of a typical spent fuel pool from 1100 fuel ele-ments stored in high density racks showed a radiation level of about 10-8 mrem /hr. Thus the direc.t radiation dose rate levels from the fuel assemblies themselves is not an important part of the total dose rate in the spent fuel pool area.
The major contribution of dose rate in the-spent fuel pool area comes from introduction of reactor conlant water into the pool a'rea during,
refueling.
Dislodging of crud (activation products) from the surface of an assembly during fuel ' handling, radioactivity in the reactor coolant water from fuel' leaks, and leakage of radioactivity from the stored spent fuel provides the radioactivity in the pool.
Thus, the increase in the number of fuel.
elements in the pool due to the spent fuel pool modification should not cause a significant incr. ease in the radionuclide concentration and subsequent increase in dote rate.
Gamma ' isotopic concentrations ind'icate that the contribution' from the 60Co, 134Cs, 13{Csand 58 o activities provides the major source of dose rate above the pool.
C Most of the activation products producing this dose rate comes from the water interchange of the primary coolant water during transfer from the reactor during refueling. Many of these products'will be removed t om the pool 'by the spent fuel pool clean-up system. Therefore the monitoring equipment used 9
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at the: pool are essentially low range survey meters which provide dose rate.
data to occupants in the spent fuel pool area during the fuel transfer and eventual clean-up. These radiation surveys are performed independent of the u
Jmodification to assure that exposures to personnel occupying the pool area will be maintained ALARA during all spent fuel pool operations.
Additionally, 6 remote area monitors (RAMS) have been installed as follows:
two are on the west wall adjacent to the pool in a general occupied area; one monitors Unit 1 pool while the other monitors Unit 2 pool. They have a sensitivity range of 0.01 to 100 mr/hr and are in a background expected to be 1 mr/hr.
The alarm J
set-point for these monitors is 5 mr/hr and they have local and control room
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read-out and alarm. Two additional monitors are at the same location as the previous two, bu't have sensitivity ranges of from 10 to 106 mr/hr and an alarm set point of 100 mr/hr. They serve as monitors for Unit 1 and Unit 2 pools that will initiate the standby gas treatme'nt system and isolate the Reactor Building Ventilation System in case of abnormal releases. These monitors have control room read-out and alarm.
The fifth RAMS is on the fuel loading crane and will always be at location of crane. work.
It has a range of from 0.1 to 1000 mr/hr, and local read-out and alarm at 15 mr/hr.
The last RAMS
- is located at the east wall and is adjacent to the equipment hatch.
It has a range of 0.01 to 100 mr/hr and set to alarm at 15 mr/hr.
It also has con-The 'ose rate ranges and set points described d
trol room read-out and alarm.
above will not be.affected as a result of the modification.
Besides the RAMS systems in the spent fuel pool area, continuous airborne radioactivity monitors (CAMS) are available which can be used to [nonitor RU
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any airborne radioactivity that may be generated in the SFP area. These monitoring systems use scintillation detectors and GM detectors to monitor for iodine and particulates respectively. Their sensitivity ranges from 10 to 106 counts per minute and a variable set point alarm is available so that the alarm set point can be determined based on the background in the area to be monitored. The count rate is continuously recorded on chart paper.
There are no radiation r::itors which continuously and directly monitor the spent fuel pool water.
Direct pool water monitors are not needed, although they can be acceptably sensitive devices for monitoring spent fuel pool wate,r under certain conditions (e.g. on-line monitoring of water upstream of clean-up system pipe lines).
However, the existing area radiation monitors, airborne radioactivity monitors and portable survey meters are adequate to detect any changes in background radiation levels around the spent fuel pool that could
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result in significant occupational exposure. 'Thereby, spent fuel pool water monitors are not necessary for maintaining occupational exposure ALARA.
Experience has 'lso indicated that there is little radionuclide leakage from a
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spent fuel stored in the pool after the fuel has cooled for several months sir}ce, as stated previously, the radionuclides that were present in the reactor coolant system prior to refueling or crud dislodged from the surface of the spent fuel during transfer, comprise the activity in the SFP water.
During and after refueling, the spent fuel pool clean-up systea reduces the
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radioactivity concentration in the water considerably.
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' In conclusion the staff feels that the radiation monitoring performed in the Quad-City spent fuel pool is adequate to detect normal and abrormal releases of radicactive materials from the increased r. umber of spent fuel bundles.
The above statements and opinions are true and correct to the best of my persona 1' knowledge and belief.
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Seymour Block, Senior Health Physicist Radiation Protection Section Radiological Assessment Branch Division of Systems Integration, NRR Subscribed and sworn to before me this f_F day of November 1981.
dudu.[ d2C), Notary Public My"CommIssionExpires: O. / / !. //? '
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. I, Roby Bevan, being duly sworn, state that I am an employee of the U.S. Nuclear Regulatory Comission (NRC). My present position is Operating R'eactors project Manager, Operating Reactors Branch #2, Division of Licensing within the Office of Nuclear Reactor Regulation.
The purpose of my affidavit is to respond to a contention having to do with the durability and performance of Boraflex, and with corrosion of the stainless steel of the racks.
An exact statement of the contention and j
my response to that contention follows.
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Contention 4 Intervenors contend that Licensees' application to install its proposed spent fuel storage racks should be denied as a.
the durability and performance of the Boraflex in the spent fuel pool water environment is unknown and unsubstantiated, and b.
the corrosion rate of the stainless steel in the racks in unknown, and may result in their structural failure, thereby failing to provide a reasonable assurance of public health and safety.
Response to Contentions 4a. and b.
The staff has completed a review of portions of the Licensees' application, including an evaluation of the durability and performance of the Boraflex neutron absorber material and the corrosion behavior of the stainless steel in the racks. This evaluation has been officially trans-mitted from the Division of Engineering to the Division of Licensing for inclusion in the forthcoming Safety Evaluation Report on the Quad Cities Station augmented spent fuel storage application.
The material in this evaiuation addresses the concerns expressed by the Intervenors, and a copy is attached hereto in response to the stated concerns.
The attached report might be changed somewhat by editing before inclusion in the forthcoming Safety Evaluation Report.
It is not anticipated, however, that any substantive or conclusory changes will be made unless unexpected new information that differs significantly from that on which the evaluation was based comes to light.
The above statements and opinions are true and correct to the best of my knowledge and belief.
Subscribed and sworn to before me tnis N^ day of November,1981.
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'u Roby B. Bevan, Jr.
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SAFETY EVALUATION REPORT QUAD CITIES STATION UNITS 1 AND 2 COMMONWEALTH EDIS0N CO.
DOCKET NUMBER 50-254/265 CHEMICAL ENGINEERING BRANCH CORROSION ENGINEERING SECTION 9.1.2 Spent Fuel Storage Nuclear reactor plants include storage facilities for the wet storage of spent fuel assemblies. The safety function of the spent fuel' pool and storage racks is to maintain the spent fuel assemblies in a subcritical array during all credible storage conditions. We have reviewed the com-patibility and chemical stability of the materials (except the fuel assemblies) wetted by the pool water.
In addition, our review has included an evaluation of the Boraflex neutron absorber material used in the high density storage locations for environmental stability.
There will be both the old and the new types of spent fuel storage cells"in the Quad Cities Stati.on spent fuel pools during the transition time while new storage modules are being installed. The transition period is expected to last slightly over one year. The spent fuel pool is filled with demineralized high-pur.ity, high resistivity water.
The new high-density spent fuel storage racks are of welded s' ainless steel t
construction with a "Borafle'x" neutron absorber sandwiched between the stain-less steel sheets. The neutron absorber is composed of boron carbide powder in a rubber-like silicone polymeric matrix.
The old low density fuel storage tubes provide for the interim storage of fuel assemblies and are constructed of aluminum without neutron absorber material. The anticipated corrosion of the aluminum alloys,1100 or 6061, is negligible in water of spent fuel pool quality-at -temperatures up to the boiling point of water: at 125'C (257'F) a corrosion rate of 1.5 x 10-4 mils / day has been measured for alloy 6061 aluminum, in water pH 7, which corresponds to a total corrosion of 1.1 mils in twenty years. Since the oxidation rate will continue to decrease slightly over this period, this estimate should be conservative.
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The inherent high corrosion resistance of aluminum and stainless steel makes them well suited for use in demineralized water. Aluminum and stainless steel fuel storage racks submerged in water have been in use for 10 years with no deterioration evident.
Aluminum and 300-series stainless steel are very similar insofar as their coupled potential is concerned.
Because the pool water has very low con-ductivity, galvanic corrosion should not occur. The use of stainless steel fasteners in aluminum to avoid detrimental galvanic corrosion is a recommended practice and has been used successfully for many years by the aluminum industry.
The pool liner, rack lattice structure and the high density fuel storage tubes are stainless steel which is compatible with the storage pool environ-ment.
In this environment of oxygen-saturated high purity water, the corrosive deterioration of the type 304 stainless steel s'hould not exceed a depth of 6.00 x 10-5 inches in 100 years, which is negligible relative to the initial thickness.
Dissimilar metal contact corrosion (galvanic attack) between the stainless steel of the pool liner, rack lattice struc-ture, fuel storage tubes, and the Inconel and the Zircaloy in the spent fuel assemblies will not be significant because all of these materials are protected by highly passivating oxide films and are therefore at similar potentials.
The Boraflex poison material is composed of non-conductive materials and therefore will not develop a galvanic poter.tial in contact with the metal components. Boraflex has undergone extensive testing to study the effects of gamma irradiation.in various environments, and to verify its structural integrity and suitability as a neutron absorbing material.
The space which contains the Boraflex is vented to the pool. Venting will allow gas generated by the chemical degradation of the silicone polymer binder during heating and irradiation to escape, and will prevent. bulging or swelling of the stainless steel tube.
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the materials will compromise the integrity of the racks, the applicant has ' committed to conduct a long tenn fuel storage cell surveillance pro-Surveillance samples are in the form of removable stainless steel gram.
clad Boraflex sheets, which are proto-typical of the fuel storage cell wall s.
These specimens will be removed and examined periodically.
From our evaluation as discussed above we conclude that the corrosion that will occur in the spent fuel storage pool environment should be of little significance during the remaining life of the plant.
Components in the spent fuel storage pool are constructed of alloys which have a low differential galvanic potential between them and have a high resistance to general corro-sion, localized corrosion, and galvanic corrosion. Tests under irradiation and at elevated temperatures in water indicate that the Boraflex material will not undergo significant degradation.during the expected service lif,e of 40 years.
We further conclude that the environmental compatibility and stability of
'the materials used in the spent fuel. storage pool are adequate, based on test data and actual service experience in operating reactors.
We have reviewed the surveillance program and we conclude that'the monitoring of the materials in the spent fuel storage pool, as proposed by the licensee, will provide reasonable assurance that the Boraflex material will continue to perform its function for the design life of the pool. We therefore find that the implementation of a monitoring program and the selection of appropriate materials of construction by the licensee meet the requirements of 10 CFR Part 50, Appendix A, Criterion 61, by[having a espaEility to perm'it ~
appropriate periodic inspection and testing of components, and Criterion 62, by preventing criticality by maintaining structural integrity of components and of the b'oron poison.
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i I Roby Bevan, being duly sworn, state that I am an employee of the U.S. Nuclear Regulatory Commission (NRC). My present position is Operating Reactors Project Manager, Operating Reactors Branch #2, Division of Licensing within the Office of Nuclear Reactor Regulation.
.The purpose of my affidavit is to respond to a contention having to do with-the adequacy of the spent fuel pool cooling systems and the adequacy of the spent fuel pool cleanup systems. An exact statement of the contention and my response to that contention follows.
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Contention 5 Intervenors contend that in the light of the increase in decay heat which will result from the proposed increase in the spent fuel pools' storage capacity, the current capacity of the radioactive waste treatment and cooling system for the spent fuel pools will be inadequate for the proposed modification, therby failing to provide the requisite assurance of public health and safety.
Response to Contention 5 In response to the part of the contention concerning the adequacy of the pools' cooling system, reference is made to the response given for contention 1.
As stated there, the presently installed pool cooling capability is more than sufficient to handle the heat load with the pool filled to the limit of the proposed capacity. At present, the pool heat load is held by using only one of two cooling loops for each of the two units.
Should the reracking proposal be implemented and the new storage spaces ha gradually filled up over the years, the average age of the spent fuel in the pool will increase, so that the average decay rate and heat load per assembly stored will decrease.
Should the pools be filled to capacity in this manner at some time in the future, the heat load on the pool will have been increased by only 50% or less over what is is now.
This is well within the present cooling capability of the system.
In response to the part of the contention concerning the adequacy of the radioactive " waste treatment system --- for the spent fuel pools,"
some clarification is in order. Strictly speaking, there is no such system; we believe, however.that the contention is meant to refer to the spent fuel pool cleanup system. This is the system that provides for the 1
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removal of radioactive materials, corrosion products and other impurities from the pool.
The staff has completed its review of that portion of the Licensees' application having to do with the spent fuel pool cleanup system.
This evaluation has been officially transmitted from the Division of Engineering to the Division of Licerising for inclusion in the forthcoming Safety Evaluation Report on the Quad Cities Station augmented spent fuel storage application. The material in this evaluation addresses the concerns expressed by the Intervenors and a copy is attached hereto in response to the stated concerns.
The attached report might be changed somewhat by editing before inclusion in the forthcoming Safety Evaluation Report.
It is not anticipated, however, that any substantive or conclusory changes will be made unless unexpected new information that differs significantly from that on which the evaluation was based comes to light.
The above statements and opinions are true and correct to the best of nly knowledge and belief.
Roby B. Bevan, Jr.
Subscribed and sworn to before me this O ra day of November, 1981.
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO EXPANSION OF QUAD CITIES STATION UNITS 1 & 2 SPENT FUEL POOL STORAGE DOCKET NO. 50 - 254/2'5 SPENT FUEL POOL CLEANUP SYSTEM I.
INTRODUCTION The spent fuel pool cleanup system consists of a filter demineralizer (precoat filter material and powdered anion.and cation resin), filters, and associated piping, valves, and fittings.
The
. system is designed to remove corrosion products, fission products, and impurities from the pool water.
Pool water purity is monitored by a continuous conductivity meter installed on the inlet to the fuel pool demineralizersi and by periodic grab samples for laboratory analysis.
Once a week a representative grab sample is obtained from the fuel pool demineralizer inlet line for p i for chlorider silicar and turbidity a'n a l y s i s.
Weekly activith checks are made f or gross bett and gross alpha.
Once a month a sample from the same location is obtained for a gamma isotopic analysis.
All peaks are identified.
All identified isotopes are quantified, and an.LLD is determined for,K -85.
r The criterion for a demineralizer b6ckwash and precoat is a consistent excursion from the chemistry. limits, or high differential pressure (25 psid) across the deminer~alizer.
We agree with the licensee that the proposed high density fuel storage will not al.ter 'the chemistry or radiochemistry of the spent fuel pool water.
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EVALUATION Past experience showed that the greatest increase in radioactivity and impurities in spent fuel pool water occurs during refueling
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and spent fuel handling.
The refueling frequency, the amount of core to be replaced for each fuel cycter and frequency of operating the spent fuel pcol cleanup system are not expected to increase as a result of high density fuel storage.
The chemical and radionuclide composition of the spent fuel pool water is not expected to change as a result of the proposed high density fuel storage.
Past experience also shows n'o significant Leakage of fission products from spent fuel stored in pools occurs after
- the fuel has cooled for several months.
To maintain water quality, the Licensee has estabLjshed the fr'equency o~f chemic'al and radionuctide analysis that wilL be performed t o monitor the
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water quality and the need for spent fuel pool cleanup system demineralizer resin and filter replacement.
In addition, the
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Licensee has also set the chemical and radioch.emical Limits to be used in monitoring the spent fuel pool water quality and initiating corrective action.
We agree with the Licensee's contentionse' that the increased quantity of spent fuel to be stored wilL not contribate s,ignificantly to the amount of radioactivity from fission products in the spent fuel pool water.
We conclude tha,t the proposed expansion of the spent fuel pool wiLL not appreciably affect the capability and capacity of the existing spent fuel pool cleanup syste3 More frequent replacements of filters or demineralizer resin, required when E
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J the differential pressure exceeds 25 psid or decontamination effectiveness is-reduced as indicated by the licensee, can offset any potential increase in radioactivity and impurities in the pool water as a result of the expansion of stored spent fuel.
Thus we have determined that the existing fuel pool cleanup syst'em with the proposed I.igh density f uel s torage (1) provides the-capability and capacity of removing radioactive materialse corrosion products, and impurities from the pool and thus meets the requirements of General' Design Criterion 61 in Appendix A of 10 CFR P, art 50 as it relates to appropriate systems to fuel storage; (2) is capable of reducing occupational exposures to radiation by removing radioactive products from the popl water, and thus meet the requirements of Section 20.1(c) 'o f 10 CFR Part 20, as it relates to maintaining radiation exposures as low as is reasonably achievable; (3) confines radioactive materials in the pool water into the filters and demineralizers, and th'us meets Regulatory Position C.2.f(c) of Regulatory Guide 8.8, as it relates t'o reducing the spread of contaminants from the source; and (4) removes suspended impurities from pool water by filters, and thus meets Regulatory Position C.2f(3) of 8egulatory Guide 8.8, as'it relates to removing crud from fluids thr'ough physical action.
CONCLUSION On the basis of the above evaluation, we conclude th,at the existing spent fuel poo.l. cleanup system meets GDC6'1r Section 20.1(c) of 10 CFR Part 20 and the appropriate sections of Regulatory Guide 8.8 and, thereforer is acceptable-for the proposed high density fuel storage.
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