ML20083H830
| ML20083H830 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 12/15/1983 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20083H798 | List: |
| References | |
| NUDOCS 8401050048 | |
| Download: ML20083H830 (11) | |
Text
8[kf t UNITED STATES
%.g% e, )' o NUCLEAR REGULATORY COMMISSION E
WASHINGTON. D. C. 20555 s. vja s.... f
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ENVIRONMENTAL IMPACT APPRAISAL BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTbG AMENDMENT N0.61TO FACILITY OPERATING LICENSE N0. DPR-71 AND SU9POR[ LNG AMENDMENT N0.8/TO FACILITY OPERATING LICENSE NO. OPR-62
' RELATING TO THE MODIFICATION OF THE SPENT FUEL STORAGE P0OL CAROLINA POWER & LIGHT COMPANY 2RUNSWICK JTEAM ELECTRIC PLANT, UNITS 1 AND 2 DOCKET NOS. 50-325 AND 50-324
- 1. 0 INTRODUCTION AND DISCUSSION The combined spent fuel storage capacity of the two nuclear units at Brunswick Station was originally 1440 BWR fuel assemblies, or storage for approximately 1.3 cores from each of the two units.
This capability was later increased by a modular, rack aesivi to a maximum of 616 PWR or 1386 BWR assemblies.
In actualf:y tne installed storage capabity was for 304 PWR and 2088 BWR assemolies at tne plant.
This 11miteo storage capability was in Keeping with the expectation generally i' eld in the industry that spent fuel would be kept onsite for a period of 3 to 5 years and then shipped offsite for reprocessing and recycling of tha fuel.
. Reprocessing of spent fuel did not develop as had been anticipated, however, and in September, 1975, the Nuclear Regulatory Commission (NRC, the Commission) directed the NRC staff (the' staff) to prepare a Generic Environmental Impact 5tatement'(GEIS, the Statement) on spent fuel storage.
The Commission directed the staff to analyze alternativas for the handling and storage of spent light water power reactor fuel with particular emphasis on developing long range policy.
The Statement wouid consider alternative methods of spent fuel storage as well as the possible restriction or termination of the generation of spent fuel through nuclear power plant shutdown.
A Final Generic Environmental Impact Statement on Handling and Storage of Spent Light Water Power Reactor Fuel (NUREG-0575), Volumes 1-3 (the FGEIS) was issued by the NRC in, August, 1979.
In the FGEIS, consistent with the long range policy, the storage of spent fuel is considered to be interim storage, to be used until the issue of permanent disposal is resolved and implemented.
One spent fuel storage clternative considered in detail in the FGEIS is the expansion of onsite fuel' storage capacity by modification of the existing spent fuel pools.
Applications for fifty such spent fuel capacity increases have been reviewed and approved.
The finding in each case has t'een that the environmental impact of such increased storage capacity is negligible.
However, since there are variations in storage pool designs and limitations caused bys he spent fuel already stored in some of the pools, the FGEIS t
recommends \\thdt licensing reviews.'e dcne on a case-by-case basis to resolve i
olant specific concerns.
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,In addition to the alternative of increasing the storage capacity of the sbting spent fuel podis.fatner spent fuel storage alternatives are discussed J
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040105004hB31215 DR ADOCK 0300o324 1
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s; in ditall in the FGEIS.
The fnding of the FGEIS is that the environmental jrpact costs of interim storage are essentially negligible, regardless of where such spent fuel is stored.
A comparison of the impact-costs of the various alternatives reflect the advantage of continued generation of nuclear power versus its replacement by coal fired power generation.
In the bounding case considered in the FGEIS, that of shutting down the reactor when the spent fuel storage capacity is filled, the cost of replacing nuclear stations before the end of their normal lifetime makes this alternative uneconomical.
ibis Environrr. ental Impact Appraisal (EIA)' addresses the environmental concerns related only to expansion of the Brunswick Station spent fuel storage pools.
Additional discussion of the, alternatives to increasing the storage capacity of existing spent' fuel pools is contained in the FGEIS.
s 1.1 Description of the Proposed Action By lctter dated April 16, 1981, and supplemented by letters dated June 22 and November 23, 1981, March 16, April 5, May 20 and September 16, 1982 and February 23, March 31, and May 5,1983, Carolina Power & Light Company proposed an amendment that would allow an increase in the licensed storage capacity, of the two spent fuel pools to 3946 fuel as.semblies.
The storage cappcity would be increase compact, neutron absorbingd by replacing, some, existing racks with new, more....
racks. 'Th,is,would provide storage for spent fuel generated at Brunswick while maintaining full core off load capability at each, unit through 1987.
The environmental impacts of the Brunswick facility, as designed, were l
considered in the NRC's Final EnvironmeM al Statement (FES) issued January 1974 relative to the continuation of construction and operation of the facility.
The licensee later increased the s.torage.SA.oaC.ity..to aLmaximum.o.f 616 PWR or i
1386 BWR bundles.
The environmental impact..of this. action was considered in.
sn environmental impa'ct ' appraisal issued with our, authorization for this action l
in Amendment Nos. 8 and 30 issued August 26, 1977 In this EIA we have evaluated any additional environmental impacts which are attributable to the currently proposed increase in the SFP storage capacity for the Station, j
1.2 Need for Increased Storage Capacity Spent fuel storage pools are provided for each of the two nuclear generating units at the Brunswick facility.
Tt'e facility now has 304 PWR and 1908 BWR spaces provided by racks already installed and usable.
Of the 1908 BWR spaces, 1080 spaces are occupied by spent fuel and 828 spaces are empty.
For i
the Unit 2 maintenance outage now scheduled for Spring 1984, the full core of 560 susemblies needs to be removed and stored temporarily in order to safely t
and with minimum perscnnel exposure perform needed inspections and modifica-tions.
Of the 828 empty spaces available, 530 are located in the racks now installed in Unit 2.
Obviously this number of empty spaces will not accommo-date tne full Unit 2 cora.
Further, a spent fuel cask is not available (not licensed) to move spent fuel from Unit 2 to Unit 1 and, therefore, no way is i
available to make use of the space available in the other unit.
Therefore, 2
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additionnl space is n:cd:d in the immediate future if Unit 2 is to be able to off load the full core to perform the required maintenance.
- 1. 3 Fuel Reprocessing History l
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Currently, spent fuel is not being reprocessed en a commercial basis in the-I United States.
The Nuclear Fuel Services (NFS) plant at West Valley, New York, was shutdown in 1972 for alterations and expansion; in September 1977, NFS informed the Commission that it was withdrawing from the nuclear fuel reprocessing business.
The pool is oa land owned by the State of New York.
NSF's lease with the State of New York expired in 1980 and their license has been suspended.
The State of New York has requested the utilities who own the spent fuel pre 3ently stored in the pool to remove it.
The Allied General Nuclear Services (AGNS) proposed plant in Barnwell, South Carolina, is not licensed to opera +.e.
The General Electric Company's (GE) Morris Operation (MO) in Morris, Illinois is in a decommissioned condition.
Although no plants are licensed for reprocessing fuel, the storage pool at Morris, Illinois is licensed to store spent fuel.
On May 4, 1982, the license held by GE fce spent fuel storage activities at its Morris Operation was renewed for another 20 years; GE is not accepting any additional spent fuel for storage at this facility.
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2.0 THE FACILITY The principal features of the spent fuel storage and handling at Brunswick Station as they relate to this action are described here as an aid in following the evaluations in subsequent sections of this environmental impact appraisal.
2.1 The Spent Fuel Pool (SFP)
Spent fuel assemblies are intensely radioactive due to their fresh fission product content when initially removed from the core; also, they have a high thermal output.
The SFP was designed for storage of these assemblies to allow for radioactive and thermal decay prior to shipping them to a reprocessing facility.
The major portion of decay nccurs in the first 150 days following removal from the reactor core.
After this period, the spent fuel assemblies may be withdrawn and placed in heavily shielded casks for shipment.
Space permitting, the assemblies may be stored for longer periods, allowing continued fission product decay and thermal cooling.
2.2 SFP Cooling System The spent fuel and cooling system (SFPCS) for each unit at the Brunswick Station consists of two pumps in parallel, with a pump and heat exchanger in series.
The heat removal design capability is 6.53 x 108 Btu /hr at 125*F and 12.0 x 106 Btu /hr at 150*F.
The residual heat removal system (RHR) can be crosstied with the SFPCS in the event supplemental heat removal capability is required.
Heat is transferred from the spent fuel pool cooling system to the reactor building closed cooling water system.
The reactor building closed cooling water system, in turn, transfers heat to the service water system.
The RHR system is also a closed system cooled by service water.
The service water system is a once-through cooling system in which well water or strained water from the Atlantic Ocean is supplied from pumps in the intake structure and returned to the ocean after removing heat from a number of systems, including the reactor building closed cooling water and the RFR systems.
- 2. 3 Radioactive Wastes The plant contains waste treatment systems designed to collect and process the gaseous, liquid and solid waste that might contain radioactive material.
The waste treatment systems are evaluated in the NRC's Final Environmental State-ment (FES) dated January, 1974.
There will be no change in the waste treat-ment systems described in Section III.D.2 of the FES because of the proposed modification.
- 2. 4 Spent Fuel Pool Cleanup System The SFP cleanup system is part of the pool cooling system.
It consists of a demineralizer with inlet and outlet filters, and the required piping, valves, and instrumentation.
There is also a separate skimmer system to remove surface dust and debris from the SFP.
This cleanup system is similar to such systems at other nuclear plants which maintain concentrations of radioactivity in the pool water at acceptably low levels.
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3.0 ENVIRONMENTAL IMPACTS OF THE PROPOSED ACTION 3.1 l
Nonradiological Consequences of the Proposed Action The nonradiological environmental impacts of Brunswick, as designed, were considered in the FES issusa January, 1974.
Increasing the number of assemblies stored in the existing fuel pools will not cause any new nonradio-logical envirormental impacts not previously considered.
The amounts of waste heat emitted by each of the units as a result of the proposed increased spent fuel storage capacity will increase slightly (less than one percent), but will result in no measurable increase in impacts upon the environment.
- 3. 2 Radiological Consequences of the Proposed Action 3.2.1 Introduction The potential offsite radiological environmental impact associated with the expansion of spent fuel storage capacity at Brunswick has been evaluated.
During the storege of the speni fuel under watcr, both volatile and non-volatile radioactive nuclides may be released to the water from the surface of the assemblies or from defects in the fuel cladding.
Most of the material released from the surface of the assemblies consists of activated corrosion products such as Co-58, Co-60, Fe-59 and Mn-54, which are not volatile.
The radic-nuc', ides that might be released to the water through defects in the cladding, such as is-134, Cs-137, Sr-89 and Sr-90, are also precominantly non-volatile at the temperature conditions that exist in peal storage.
The primary impact of such non-volatile radioactive nuclides is their contribution of radiation levels to which workers in and near the SFP would be exposed.
The volatile fission product nuclides of most concern that might be released through' defects in the fuel cladding are the noble gases (xenon and krypton), tritium and the focine isotopes.
Experience indicates that there is little radionuclide leakage from spent fuel stored in pools after the fuel has cooled for several months.
The predominance of the radionuclides in the pool water appear to be radionuclides that were present in the reactor coolant system prior to refueling (which becomes mixed with water in the spent pool during refueling operations), or crud dislodged from the surface of the spent fuel during transfer from reactor core to the SFP.
During and after refueling, the spent fuel pool cleanup system reduces the radioactivity concentrations considerably.
A few weeks after refueling, the spent fuel cools in the pool so that the fuel cladding temperature is relatively cool, approximstely 180 F.
This substantial temperature reduction reduces the rate of release of fission products froa the feel pellets, cnd decreases the gas pressure in the gap between pellets and cladding, thereby tending to retain the fission products within the gap.
In addition, most of the gaseous fission products have short half-lives and decay to insignificant levels within a few months.
Based on operational reports submitted by licensees, and discussions with storage facility operators, there 5
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has not bsen any significant leakag2 of fission products from spInt light water reactor fuel stored in the Morris Operation (MO) (formerly Midwest l
Recovery Plant) at Morris, Illinois, or at Nuclear Fuel Services' (NFS) storage pool at West Valley, New York.
Spent fuel has been stored in these two pools I
which, while it was in a reactor, was determined to have significant leakage and was therefore removed from the core.
After storage in the onsite spent
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fuel pool, this fuel was later shipped to either M0 or NFS for extended storage.
l Although the fuel exhibited significant leakage at reactor operating conditions, there was no significant leakage from this fuel in the offsite storage facility.
3.2.2 Radioactive Material Released to the Atmosphere With respect to releases of gaseous materials to the atmosphere, the only radioactive gas of significance which could be attributable to storing addi-tional fuel assemblies for a longer period of time would be the noble gas radionuclide Krypton-85 (Kr-85).
As discussed previously, experience has demonstrated that after spent fuei has decayed 4 to 6 months, there is no longer a significant release of fission products, including Kr-85, from stored fuel containing cladding defects.
One hundred forty (140) fuel assemblies are expected to be stored following each March refueling at Unit 1 and each November refueling at Unit 2.
Since space must be reserved to accomacdate a complete reactor core unloading operation (nominally 560 fuel assemblies), and module spaces are reserved for PWR fuel assemblies, the useful pool capacity is 901 fuel assemblies at Unit 1 and 1243 fuel assemblies et Unit 2.
At an input of 140 fuel assemblies per year, the storage capacity is approximately 9 years at Unit 2 and 6.5 years at Unit 1.
For the simplest case, we assumed that all of the Kr-85 that is going to leak from defected fuel is going to do so in the 12 month interval between refuelings.
In other words, all of the Kr-85 available for release is assumed to come out of the fuel before the next batch of fuel enters the pool.
Our calculations show that the expected release of Kr-85 from a 140 fuel assembly refueling is approximately 62 Ci each 12 months.
As far as potential dose to offsite populations is concerned, this is actually the worst case, since each refueling would generate a new batch of Kr-85 to be released.
As more and more fuel is ddded to the pool, one might think that this would increase the releases, but according to the terms of our model, this is not the case since all of the Kr-85 available for release has already lef t the defected fuel previously stored in the pool before the next batch enters, with the result that the annual releases are not cumi lative but remain approximately the same.
In other words, the enlarged capacity of the pool has no effect on the total amount of Kr-85 released to the atmosphere each year.
Thus, we conclude that toe proposed modifications will not have any significant impact on exposures offsite.
Assuming that the spent fuel will be stored onsite for several years, Iodine-131 releases from spent fuel assemulies to the SFP water will not be significantly increased because of the expansion of the fuel ctorage capacity since the Iodine-131 inventory in the fuel will decay to negligible levels between refuelings for each unit.
Storing additional spent fuel assemblies is not expected to increase the bulk water temperature during normal refuelings above the 150 F used in the design 6
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analysis.
Therefore, it is not expected that there will be any significant change in the annual release of tritium or iodine as a result of the proposed modifications from that previously evaluated in the FES.
Most airborne releases of tritium and iodine result from evaporation of reactor coolant, which contains tritium and iodine in higher concentrations than the spent fuel pool.
Therefore, even if there were a higher evaporation rate from the spent fuel pool, the increase in tritium and iodine released from the plant as a result of the increased stored spent fuel would be small compared to the amount normally released from the plant and that which was previously evaluated in the FES.
If it is desired to reduce levels of radioiodine, the air can be diverted to charcoal filters for the removal of radioiodine before release to the environ-ment.
In addition, the station radiological effluent Technical Specifications which are not being changed by this action, limit the total releases of gaseous activity.
3.2.3 Solid Radioactive Wastes The concentration of radionuclides in the pool water is controlled by the filters and the demineralizer and by decay of short-lived isotopes.
The activity is highest during refueling operations when the reactor coolant water is introduced into the pool, and decreases as the pool water is processed through the filters and demineralizer.
The increase of radioactivity, if any, due to the proposed modification, should be minor because of the capability of the cleanup system to continuously remove radioactivity in the SFP water to acceptable levels.
The licensee does not axpect any significant increase in the amount of solid waste generated from the spent fuel pool cleanup systems due to the proposed modification.
While we agree with the licensee's conclusion, as a conserva-tive estimate we have assumed that the amount of solid radwaste may be increased by an additional two resin beds a year due to the increased operation of the spent fuel pool cleanup system.
The annual average volume., per unit, of solid wastes shipped from the Brunswick Plant during 1978 through 1980 was 15,000 cubic feet.
If the storage of additional spent fuel does increase the amount of solid waste from the SFP cleanup systems by about 160 cubic feet per unit per year, the increase in total weste volume shipped would be approximately 1% and would not have any significant additional environmental impact.
The present spent fuel racks to be removed from the SFP because of the proposed modification are contaminated and will be disposed of as low level solid waste.
We have estimated that approximately 7000 cubic feet of solid radwaste will be removed from the plant because of the proposed modification.
Averaged over the lifetime of the plant this would increase the total waste volume shipped from the facility by less than 3%.
This will not have any significant additional environmental iraact.
3.2.4 Radioactive Material Released to Receiving Waters There should not be a significant increase in the liquid release of radionuclides from the plant as a result of the proposed modification.
Since the SFP cooling and cleanup system operates as a closed system, only water originating from cleanup of SFP floors and resin sluice water need be considered as potential sources of radioactivity.
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It is expected that neither the quantity nor activity of the floor cleanup water will change as a result of this modification.
The SFP demineralizer resin removes soluble radioactive material from the SFP water.
These resins are periodically sluiced with water to the spent resin storage tank.
The amount of radioactivity on the SFP demineralizer resin may increase slightly due to the additional spent fuel in the pool, but the soluble radioactive material should be retained on the resins.
If any radioactive material is transferred from the spent resin to the sluice water, it will be removed by the liquid radwaste system for processing.
After processing in the liquid radwaste system, the amount of radioactivity released to the environment as a result of the proposed modification would be negligible.
3.2.5 Occupational Radiation Exposures We have reviewed the licensee's plans for the removal and disposal of the low density rocks and the installation of the high density racks with respect to occupational radiation exposure.
The occupational exposure for the entire operation in estimated by the licensee to be about 81 man-rem.
We consider this to be a reasonable estimate because it is based on realistic dose rates and occupancy factors for individuals performing a specific job during the pool modification.
This operation is expected to be a small fraction of the total annual man-rem burden from occupational exposure.
We have estimated the increment in onsite occupational dose resulting from the proposed increase in stored fuel assemblies,on the basis of information supplied by the licensee for dose rates in the spent fuel pool area from radionuclide concentrations in the SFP water and from the spent fuel assemblies.
The spent fuel assemblies themselves vill contribute a negligible amount to dose rates in the pool area because of the depth of water shielding the fuel.
Consequently, the occupational radiation exposure resulting from the additional spent fuel in the pool represents a negligible burden.
Based on present and projected operations in the spent fuel pool area, we estimate that the proposed modification should add less that one percent to the total annual occupational radiation exposure burden at this facility.
Thus, we conclude that storing additional fuel in the SFP will not result in any significant increase in doses received by occupational workers.
3.3 Environmental Impact of Spent Fuel Handling Accidents Although the new high density racks will accommodate a larger inventory of spent fuel, we have determined that the installation and use of the racks will not change the radiological consequences of a postulated spent fuel handling accident, and a fuel shipping cask drop accident, in the SFP area, from those values previcusly reported in the Brunswick FES, based on the following considerations.
The heaviest identified load with this modification is a 15 x 17 rack weighing 16 tons, whereas the main hoist on the reactor building crane is rated at 125 tons.
From a previous review we had concluded that the overhead crane load handling system and Technical Specifications meet our requirements and are acceptable.
Spent fuel casks are of course not permitted over spent fuel stored in the pool.
Further the licensee's spent fuel storage cask is not 8
currently licensed for use.
The only items transported over spent fuel are other fuel assemblies, pool canal gates, and a fuel channel measuring device, none of which approach this weight capacity of 125 tons.
We have concluded then that the likelihood of a heavy load handling accident is sufficiently small that the proposed modifications are acceptable, and no additional restrictions on load handling operations in the vicinity of the SFP are required.
3.4 Radiological Impacts to the Population The proposed increase of the storage capacity of the SFP will not create any significant additional radiological effects to the population.
The additional total body dose that might be received by an individual at the site boundary, and by the estimated population within a 50-mile radius, is less than 0.10 mrem /yr i
and 0.001 man-rem /yr, respectively.
These doses are small coepared to the fluctuations in the annual dose this population receives from background radiation.
The pcpulation dose represents an increase of less than 0.01 percent of the dose previously evaluated in the FES for the Brunswick Steam Electric Plant, Units 1 and 2.
We find this to be an insignificant increase in dose to the population resulting from the proposed action.
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SUMMARY
The findings contained.in the Final Generic Environmental Statement on Handling and Storage of Spent Light Water Power Reactor Fuel, (the FGEIS) issued by the NRC in August, 1979, were that the environmental impact of interim storage of spent fuel was negligible, and the cost of the various alternatives reflect the advantage of continued generation of nuclear power with the accompanying spent fuel storage.
Because of the differences in spent fuel pool designs, the FGEIS recommended licensing spent fuel pool expansions on a case-by-case basis.
Expansion of the spent fuel storage capacity at Brunswick Station does not significantly change the radiological impact evaluated by the NRC in the FES issued in January,1974.
As discussed in Section 3.4 of this EIA, the additional total body dose that might be received by an individual at the site boundary or the estimated population within a 50 mile radius is less than 0.10 mrem /yr and 0.001 man-rem /yr respectively, and is less than the natural fluctuations in the dose this population would receive from background radia-tion.
The occupational exposure for the modifications (including rack decon-tamination for on site storage) of the SFPs is estimated by the licensee to be 87 man-rem.
This is conservative.
Operation of the plant with additional spent fuel in the SFP is not expected to increase the occupational radiation exposure by more than one percent of the total annual occupational exposure at the two units.
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5.0 BASIS AND CONCLUSION FOR NOT PREPARING AN ENVIRONMENTAL IMPACT STATEMENT We have reviewed the proposed modifications relative to the requirements set forth in 10 CFR Part 51 and the Council of Environmental Quality's Guidelines, 40 CFR 1500.6.
We have determined, based on this assessment, that the proposed license amendments will not significantly affect the quality of the human environment.
Therefore, the Commission has determined that an environmental impact statement need not be prepared and that, pursuant to 10 CFR 51.5(c),
the issuance of a negative declaration to this effect is appropriate.
Principal Contributors:
R. A. Hermann T. Cain R. J. Serbu J. S. Boegli P. Wu Dated:
December 15, 1983 4
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