ML20248D472
| ML20248D472 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 08/02/1989 |
| From: | Hodgdon A NRC OFFICE OF THE GENERAL COUNSEL (OGC) |
| To: | NRC COMMISSION (OCM) |
| Shared Package | |
| ML20248D476 | List: |
| References | |
| CON-#389-8985 OL-2, NUDOCS 8908110051 | |
| Download: ML20248D472 (26) | |
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. NUCLEAR REGULATORY COMMISSION
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- In the' Matter of
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J4E PHILADELPHIA ELECTRIC COMPANY Docket Nos. 50-352-OL-2
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50-353-OL-2 (t.imerick Generating. Station i-Units l'and 2)
(SevereAccidentMitigation:
,DesignAlternatives)
NRC STAFF RESPONSE TO COMMISSION QUESTIONS 1
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Ann P. Hodgdon V
Counsel for NRC Staff
. August 2, 1989 1
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August 2, 1989 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE COMMISSION O
In the Matter of PHILADELPHIA ELECTRIC COMPANY
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Docket Nos. 50-352-OL-2
)
50-353-0L-2 (Limerick Generating Station
)
Units 1 and 2)
)
(Severe Accident Mitigation
)
Design Alternatives)
NRC STAFF RESPONSE TO COMMISSION QUESTIONS On July 26, 1989, the Nuclear Regulatory Commission (Commission) issued a Memorandum and Order in which, among other things, it directed the NRC Staff to file responses to five questions. The five questions sought information for use in the Commission's effectiveness review of Linerick Unit 2 full power operation.
The Staff's answers to the questions follow. Affidavits identifying the person who prepared each answer together with that person's professional qualifications are also provided.
Q.1.
Provide an evaluation of the incremental increase in occupational radiation exposure associated with postponing the installation of SAMDAs to the first refueling outage.
Answer:
The staff is currently performing an evaluation of severe accident mitigation design alternatives for the Limerick Generating Station in response to the February 28, 1989 Court of Appeals decision which held that the NRC had failed to consider mitigation alternatives as required by 4
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the National Environmental Policy Act of 1969. The staff evaluation is considering the six mitigation alternatives which the Appeal Board in
'ALAB-819 indicated were supported with the required bases and specificity, D
as well as other mitigation alternatives, as appropriate, which were considered in the Containment Performance Improvement Program being conducted by the Office. of Nuclear Regulatory. Research within the NRC.
The staff evaluation is scheduled for issuance by August 16, 1989.
As part of this evaluation, the staff requested information from the licensee with regard to severe accident mitigation, including cost / benefit analyses'for mitigation alternatives as well as information relating to occupational exposures incurred in the installation of various mitigation alternatives.
In response, the licensee has provided the following information with regard to the six mitigation alternatives which the Appeal Board indicated were supported with the required bases and specificity. For each alternative, the estimate of the installation hours required in a radiologically controlled area and the estimated occupational exposure incurred in installation are given. The licensee assumed that installation work would be performed after the first fuel cycle.
In the licensee's analysis, dose rates which were measured at Limerick Unit I during its first and second refueling outage, adjusted to reflect achievable dose rates from the use of temporary shielding and from decontamination efforts, were used in the calculation of estimated occupational exposure values. The mitigation alternatives for which data are provided were described in a June 23, 1989 licensee submittal to the NRC, and are generally comparable to the descriptions of the corresponding
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systems presented in NUREG/CR-4025, titled " Design and Feasibility of Accident Mitigation Systems for Light Water Reactors," dated August 1985.
The staff notes that the following constitute estimates of the incremental i
increases in occupational radiation exposure incurred in the installation
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of mitigatior alternatives after the first fuel cycle as compared with installation prior to achieving reactor criticality.
Ir.cremental increases in occupational exposure for installation after the first fuel cycle as compared with installation after low power testing were not i
derivea.
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i Pool heat removal system: 21,000 installation hours, 58 person-rem.
I Drywell spray (with new spray header): 61,000 installation j
hours, 416 person-rem.
Anticipated transient without scram vent:
15,000 installation hours, 14
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person-rem.
Filtered vent (with gravel bed filters):
5,400
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i installation hours, ? person-rem.
I Core debris control:
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Dry crucible below basemat: 80,000 installation hours, 173 j
person-rem.
Wet rubble bed: 20,900 installation hours, 14 person-rem.
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Large containment vacuum breaker:
no estimates provided by the licensee.
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With regard to the large containment vacuum breaker, the staff considers that the occupational radiation exposure incurred in its installation would be comparable to that of the filtered vented containment system.
The licensee did not perform a cost analysis for this mitigation alternative because it concluded that no quantifiable benefit for the mitigation of the consequences of a severe accident would result from the installation of the large containment vacuum breaker.
Although an assessment of the bases for the above results provided by the licensee is ongoing as part of the staff evaluation, the staff's impression of the licensee results is that they are generally reasonable.
In the staff's response to the utility's June 5, 1989 Motion filed with the Commission, information regarding the occupational exposure 'ncurred in the installation of the wet rubble bed core retention device was presented in an attached affidavit. The estimates indicated in th?
affidavit were a bounding calculation in that it was assumed that all work was performed in a 40 mrem per hour radiation area. The work hour estimates, derived from NUREG/CR-4025, included all work related to the installation of the rubble bed core retention device, and thus included work in non-radiologically controlled areas. The information provided for work hour estimates in NUREG/CR-4025 did not allow conclusions as to which portions of the work would be performed in radiologically controlled areas. The staff evaluation is also considering mitigation alternatives, as appropriate, which are being considered in the Containment Performance Improvement Program.
These alternatives are generally less costly and require fewer and less extensive hardware modifications to the plant. The
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staff believes that the occupational exposure incurred in the installation
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of these ' alternatives is bounded by the estimates provided by the licensee for the six mitigation alternatives indicated in ALAB-819.
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Q.2. Provide an evaluation of the incremental environmental effects from the risk of severe accidents of operation of Limerick with no SAMDAs in place.for one fuel cycle.
Response
The Final Environmental Statement for Limerick provides estimates of societal risks from severe accidents initiated by internal events and external events (seismic, fire,'and floods). Estimated values for selected risk measures are reproduced in Table 1.
The risk estimates were based on core damage frequency estimates. appropriate at that time.
Sincethestaffreview(1984),.thelicenseehasmadenumerous modifications to plant hardware and procedures as described by the utility in a June 23, 1989 submittal and described in a July 27, 1989 meeting with i
the staff. Two of~the modifications made by the licensee were in response to insights / recommendations identified in NLiREG-1068. These involve improvedAutomaticDepressurizationSystem(ADS)initiationlogic
.following the potential loss of high pressure coolant sources, and improved design to achieve an alternate method of room cooling for High Pressure Injection systems during loss of offsite power events.
The staff considers these improvements to be worth a factor of 2.5 reduction in core
. damage frequency for the most likely accident scenarios. As a result, the l:
FES estimates of risk would be reduced by nearly a factor of 2.5.
Table 2 l
presents these reduced values of risk.
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'Because the severe accident risk associated with not operating Limerick 2 j
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is zero, the values. in Table 2 represent the incremental risk of operation for one fuel cycle without additional SAMDAs.-
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To place these risk estimates in perspective, the FES concluded.that the early fatality risk to an individual within one mile of the plant is a very small fraction of the risk to the teme individual cf accidental death from all other sources.
In addition,- the latent fatality risk to the population living within'50 miles'of the plant is a very small fraction of the cancar fatality risk in the same population from all other causes.
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~ FES, ESTIMATES OF SOCIETAL RISKS FROM TABLE 1 SEVERE ACCIDENTS, PER REACTOR-YEAR
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REFERENCE:
Estimated risk within Estimated. risk within Consequence type the 50-mile region the entire region Early fatalities with 5(-3)*
5(-3)
Supportive medical treatment (persons)
Latent cancer fatalities 4(-2) 7(-2)
(excludin
.(persons)g thyroid)
Total person-rems 7(2) 1(3)
Land area for long-term 1(3) 1(3) interdiction (m)**
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- 5(-3)=5x108 =.005
- About 2.6 million me equals to 1 mir, i
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'TdBLE? REVISED ESTIMATED VALUES OF SOCIETAL
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~ RISKS FROM SEVERE ACCIDENTS Estimated risk within Estimated risk within.
Consequence type the 50-mile region the entire region i
Per Reactor One Fuel Per Reactor One Fuel-j Year Cycle Year Cycle-Early fatalities with 5(-3) 8(-3) 5(-3) 8(-3)
Supportive medical treatment (persons)
Latent cancer fatalities 3(-2)
'4(-2) 4(-2) 6(-2)
(excludin (persons)g thyroid)
Total ~ person-rems 5(2) 7(2).
7(2) 1(3)
Land' area for long-term 7(2) 1(3) 7(2) 1(3) interdiction (m )
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Q.3. Provide an evaluation of the incremental environmental effect of l
generating non-nuclear replacement energy equivalent to one fuel cycle's energy production by Limerick Unit 2.
Answer:
The Final Environmental Statement (FES) related to the operation of
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Limerick Generating Station, Units 1 and 2,1984 provides a brief discussion (page 9-44 through 9-47) of the environmental impacts associated with non-nuclear energy production. This discussion was used as a starting point for preparing this response. A number of assumptions were made before comparing environmental impacts of alternative energy production equivalent to one fuel cycle at Limerick.
Impacts were evaluated for the entire fuel cycle not just those associated with power plant operation. Question 2 only considered impacts associated with power plant operation since Question 2 dealt with severe accidents at the nuclear station. The period of time equivalent to one nuclear fuel cycle for Limerick Unit 2 was assumed to be 15 months. The capacity factor of the unit during this period of time was assumed to be 65%. The replacement energy was assumed to be obtained from the Mid-Atlantic Area Council (MAAC) Power Pool of which Philadelphia Electric Company is a member. The basis for the above assumptions are discussed in the response to Question 5.
It is also assumed that 65% of the replacement energy would be generated by existing coal fired facilities, and 35% from oil fired units. This mix of energy production is based on the results of a Argonne National Laboratory developed production-cost simulation model for the period 1990-91.
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With these assumptions, the response to this question becomes one of a company the coa's and oil fuel cycles to the nuclear fuel cycle for an 15 month period. The coal versus nuclear comparison has been analyzed a number of times during the late 1970's and early 1980's as part of the National Environmental Policy Act mandated review of new nuclear power facilities. One of the most comprehensive comparisons, which in earlier versions provided the basis for the comparison in the Limerick FES, is i
found in NUREG-0332.' titled " Potential Health and Environmental Impacts Attributable to the Nuclear and Coal Fuel Cycles," dated June-1987. Few environmental comparisons between oil-fired generating stations'and i
nuclear generation have been made.
L. Hamilton, in " Health and Environmental Hazards of Different Energy Systems," in " Nuclear Power Experience" Vol. 4. IAEA, 1983 (Hamilton, 1983), provides a review of occupational'. health effects of oil-fired power generation.
The capacity factor was assumed to 65% and the duration of a fuel cycle to' be 1.25 years. A rationale for.there a:sumptions is presented in the response to Question 5.
Under these assumptions a 1055 MW(e) plant will oroduce approximately 0.8 Gw(e)-yr. In comparing the two alternatives from the standpoint of environmental icpact, previous impact analyses have examined health effects to man and all other impacts to the environment that were not identified as acute or chronic impacts to either the work force or the public. Considerable effort has been expended on estimating mortality (deaths) and morbidity (injury and illnesses) associated with l'
the methods of power generation. Quantitative estimates of health impacts have been derived; however, no comparable information exists for impacts
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to the ecosystem of coal, oil and nuclear fuel cycles.
For the purposes of this response, quantitative estimates of health risk due to 0.8
- GW(e)-yr of power generation by fossil fuel (65% coal and 35% oil) and the nuclear fuel cycles is provided. A qualitative comparison of the remaining impacts associated with damage to the ecosystem is provided with some measure of relative damage. The following provides an estimate of the health effects of the replacement energy derived by both coal and oil-fired units and nuclear fuel cycles from 0.8 GW(e)-yr operation.
These estimates were derived in the late 1970's ar.d early 1980's to assist in the comparison of alternative energy sources in connection with the preparation of FES's under NEPA. While more precise numbers may exist in f
the literature, time constraints in preparing this response precluded an exhaustive literature search for more recent information.
For the coal fuel cycle, NUREG-0332 reported the health effects among tne total US population per GW(e)-yr.
Correcting the values for 0.8 GW(e)-yr results in a mortality rate of 7 to 12 and a morbidity rate of 120-160.
This includes potential mortality and morbidity to both the workers and members of the public. The various sources of risk that contribute to these values vary in the precision of the estimates.
In some cases the values represent best-estimate values found in the literature and do not represent the total range of values reported.
Furthermore, estimates of potential health risks to the public due to coal power generation, principally from stack effluents, are highly controversial and the actual
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range could vary by two orders of magnitude. Using a value af zero for the
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above risk, the low range value for morbidity would drop to 80.
For the oil-fired fuel cycle, Hamilton,1983 reported 'only occupational health risks per GW(e)-yr. Correcting these values for 0.8 GW(c)-yr results in a' mortality rate of.18 and a morbidity rate of 19. Souren of risk to the general public such as transportation accidents, refining accidents and effluents, and the health effects associated with stack effluents at the power station are not included. Since these health effects are not quantified for the purposes of this response it was conservatively assumed to be zero however they are likely to be greater than for the nuclear fuel cycle and less than the coal fuel cycle.
Based on the above health effects discussion for the coal and oil fuel cycles the mortality and morbidity associated with 0.8 GW(e)-yr of replacement power in the ratio of 65% coal and 35% oil would conservatively result in an expected mortality value of 6.2 deaths and an expected morbidity value of 98 illnesses and injuries.
For the nuclear fuel cycle NUREG-0332 reported the potential health effects among the total US population per GW(e)-yr. Correcting the values 1
for 0.8 GW(e)-yr results in a mortality rate of 1.0 to 1.4 and a morbidity rate of 14 to 27 per GW(e)-yr. Again this includes potential mortality and morbidity to both the workers and members of the public. This estimate includes the risk associated with the use of 56 Mw(e) of power by 1
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. coal combustion.for the enrichment of the nuclear fuel necessary to-
- produce one Gw(e)-y by nuclear power generation.
Ecological impacts associated with the coal, oil and nuclear fuel cycles are considerably more difficult to quantitatively compare. The impacts are often to different components of the ecosystem and vary greatly in their effect. A brief comparison of environmental impacts follows.
A modern fired plant requires approximately 3 million metric tons of coal for 0.8 GW(e)-yr. Of this, most is obtained by strip mining and transported long distances. The coal fuel cycle generates about 300,000 metric tons of solid waste'for 0.8 GW(e)-yr at the power station for disposal, usually near urban areas. This does not include any waste generated'during mining operations or coal beneficiation (cleaning).
Storage of coal ash at or near the site of generation can produce highly caustic leachates that can and often does contain high concentrations of heavy metals such as cadmium, chromium, arsenic and lead.
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Run-off from coal mined areas as well as from coal beneficiation procedures results in acid mine drainage, which adversely affects waterbodies and the aquatic biota that inhabit them. Acid precipitation also has a serious effect on aquatic biota found downwind of major centers for power generation that rely on coal for fuel.
It has also been linked with a reduction in agricultural and forest production as well cs surface erosion of man-made structures. Recently, there has been concern over the e
greenhouse effect, which links fossil fuel energy production with a global warming trend.
i The National Academy of Sciences Committee on Nuclear and Alternative Energy Systems (CONAES) concluded in 1979 that the coal fuel cycle is one w:
of the most ecologically damaging alternatives to the nuclear fuel cycle.
Production of electrical energy using oil provides a number of potential hazards to the environment.
Leakage, spillage and groundwater contamination, and saltwater intrusion are recurring problems in well-fields. Transport of oil, typically over long distances, by tanker or pipeline has the potential for serious environmental damage if an oil spill should occur. Refining results in both liquid and airborn releases that are often toxic and in some cases carcinogenic.
Storage of the oil in tank farms can result in groundwater surface runoff contamination.
Impacts associated with power generation are primarily related to stack effluents causing acid precipitation and contributing to the greenhouse effect.
A modern light-water reactor requires approximately 180,00 to 250,000 metric tons of uranium ore to produce enough 0 0 to generate 0.8 38 GW(e)-yr. Enrichment of ttle fuel adds approximately 210,000 metric tons of coal per 0.8 GW(e)-yr.
The greatest volume of wastes from the nuclear fuel cycle are the uranium mill tailings representing about 240,000 metric tons for 0.8 GW(e)-yr,
which are disposed of near the source of the ore, usually in fairly desolate areas of the western United States. Additional wastes include about 21,000 metric tons of coal ash produced in the enrichment process and the spent nuclear fuel destined for the high level waste repository.
Low level waste on the order of 800 metric tons is also generated.
Since uranium mining occurs in the more arid western portions of the United States, acid mine run off is not as significant a problem as it is in the Eastern coal mining regions. Nuclear power generation does not produce acid rain or significant quantities of CO and does not contribute 2
to the greenhouse effect.
Since the nuclear fuel cycle relies on coal generation for enrichment approximately 6% of the impacts associated with the generation of one GW(e)-yr by coal combustion is experienced by the ecosystem for each GW(e)-yr generated by the nuclear fuel cycle.
Table 1 provides a summary of impacts associated with 0.8 GW(e)-yr I
generated by the nuclear fuel cycle and impacts associated with the i
replacement energy equivalent composed of 65% coal-fired ccpacity and 35%
oil-fired capacity.
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Based on Table 1 the estimated incremental environmental effect associated with generating non-nuclear replacement energy by coal combustion and oil-fired capacity equivalent to one fuel cycle's energy production at the I
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.l-Limerick Unit 2 station is 5 deaths, 78 injuries or illnesses and a I
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significantly greater impact to the ecosystem.
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TABLE 1.
SUMMARY
OF IMPACTS FOR 0.8 GW(e)-yr -
ENERGY PRODUCTION FROM NUCLEAR VERSUS FOSSIL FUEL CYCLES 3-2 Fossii Nuclear 3
1.
Mortality, all sources frcm 6.2 1.0 to 1.4 fuel cycle for-both workers ano general public-98,4 14-27 3
2.
Morbidity, all sources.from fuel cycle for both workers and general public 0
3.
Ecological Impacts Great Small 1.
From NUREG-0332 and Hamilton 1983.
2.
Assumes,0.8 GW(e)-yr energy production, 65% by coal combustion and 35% by oil-fired capacity.
3.
Does not include health effect on the general public from oil-fired capacity.
4.
Of this value approximately 24 to.52 individuals represent morbidity to the general public from coal-fired power stations.
'The actual value could be from 0 to several hundred.
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Includes all impacts to the ecosystem that do not result in obvious acute or chronic health impacts to man.
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4 REFERENCES National Research Council " Energy in Transaction 1985-2010," National Academy of Sciences Commmittee on Nuclear and Alternative Energy Systems, Washington, D.C.
1979.
U.S. Nuclear Regulatory Commission, " Potential Health and Environmental Impacts Attributable to the Nuclear and Coal Fuel Cycles," USNRC Report NUREG-0332, June 1987.
Hamilton L. " Health and Environmental Hazards of Different Energy Systems," in Nuclear Power Experience, Vol. 4 (Vienna-International Atomic Energy Agency, 1983):
799-832.
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Q.4. Provide an evaluation of whether operation of Unit 2.for one fuel cycle would foreclose later installation of SAMDAs.
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- Answer: The. staff is~ currently performing an evaluation of severe accicent mitigation design alternatives for the Limerick Generating Station. The mitigation alternatives being considered include the six alternatives l
which the' Appeal' Board in ALAB-819 had indicated were supported with the required bases and specificity. The staff evaluation which is scheduled for completion by August 16,1989, is also considering other mitigation alternatives, as appropriate, bastd on recent results from the Containment-Performance Improvement Program being conducted by the Office of Nuclear Regulatory Research within the NRC.
The staff has considered whether operation of Limerick, Unit 2 for one fuel cycle would foreclose later installation of the mitigation alternatives being considered in its evaluation. The staff concludes th:t Unit 2 operation at full power would not aake the-installation of the mitigation alternatives physically impossible. The occupational radiation exposures incurred during installation of the mitigation alternatives after operation for one fuel cycle would be greater than exposures incurred during installation prior to achieving reactor criticality. This is because dose rates would likely be higher after power operation as a result of activation of materials in the reactor coolant system and contamination of reactor coolant surfaces. The staff concludes that the amount of occupational exposure indicated in the response to Question 1 is
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l, comparable to that which would be expected from major maintenance activities performed at operating nuclear power plants during outages.
This conclusion is based on information from documents such as (1) NRC
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- Inspection Report No. 50-286/89-13(IndianPointStation, Unit 3), dated
' June 6,1989,(2) NUREG/CR-4494, " Radiological Assessment of BWR Recirculatory Pipe Replacement," dated February 1986, and.(3)
NUREG/CR-1595, " Radiological Assessment of Steam Generator R uoval and p
Replacement: Update and Revision," dated December 1980.
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Apart from potential constraints resulting from radiological exposure
' concerns, possible constraints attributable to construction / installation L
of SAMDAs were also considered.
Because Unit 2 is a completed facility, construction / installation is more difficult and, consequently, more costly.
In tMs regard, the staff notes the June 5,1989 affidavit of Corbin A.'McNeill, Jr., Executive Vice President-Nuclear of Philadelphia Electric Company, filed with PECo's Motion to the Commission, which stated in pertinent part:
PECo would agree that, for purposes of evaluation of SAMDA's, the cost / benefit analysis of alternatives for Unit 2 could be viewed as of the time of initial licensing. Hence, the evaluation would not be skewed by l
any incremental costs associated with adding a design alternative after operation has commenced. Based upon this evaluation, the fact that Unit 2 would be operated during the pendency of a hearing would not prejudice the addition of design alternatives.
Based on Mr. McNeill's representation, cost-related factors would not foreclose later installation of any SAMDAs.
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s l Q.5. Provide an evaluation of tha' dollar cost resulting from a delay in
~ tarting up Limerick Unit 2 for a period of time equivalent to one s
fue1 cycle,
Response
The' staff estimates that a delay in starting up Limerick Unit 2 for a period of time equivalent to one fuel cycle would result in a cost of approximately $228 million (1989 dollars).
This cost estimate represents the replacement energy cost penalty associated with 15 months of. lost generation from the Limerick 2 unit 1/ eplacement energy cost refers to the during the 1990-91 timeframe.
R change in generating-system production cost that results from shutting down or delaying operation of a reactor. The change in production cost is determined from the difference betWen the total variable costs (variable fuel cost, variable 0 & H cost, and purchased energy cost) when the reactor is available for generation and when it is not. All fixed costs such as carrying charges on the capital investment are excluded from this analysis as these costs would remain independent of whether or not the reactor operates or not.
1/
The Limerick 2 fuel cycle is projected to be 18 months in duration,
~
but during the last 3 months of a fuel cycle the reactor is scheduled to be down for refueling. Thus, the incremental downtime associated with one fuel cycle is only 15 months.
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An NRC. sponsored study provides replacement energy costs for each nuclear power reactor expected to be in operation by the fall of 1991. 2/ The
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replacement' energy cost for each hypothetical reactor shutdown is determined from two production-cost simulations. The first assumes all units in a power pool, including the reactor of interest, operate normally, and the second assumes all units operate normally except the reactor of interest which is assumed to be unavailable for generation.
The model relies on extensive data files on power pool specific inventories of generating units and their associated costs, and relevant demand characteristics. Production cost simulations are performed on a power pool basis rather than for the individual utility to provide more realistic estimates that allow economy energy exchanges to be modeled directly. Based on the seasonal results reported, the average daily replacement energy cost for Limerick 2 in the 1990-91 timeframe is about
$493,000. 3,/ This estimate is expressed in 1985 dollars and assumes the Limerick 2 unit would have operated at about a 73% capacity factor. 4/
The capacity factor assumption embedded in NUREG/CR-4012 Vol. 2 is basec' on historical data for all nuclear power reactors.
It is intentionally high as it removes the effects of scheduled outages in order to allow the analyst the flexibility of explicitly incorporating planned outage 2/
NUREG/CR-4012, Vol. 2, " Replacement Er.ergy Costs for Nuclear
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Electricity-Generating Units in the United States: 1987-1991, "Argonne National Laboratory, January 1987.
3/
ibid., Table S. 1, page 3.
4/
ibid, page 97.
schedules. Since Linerick 2 will not have a refueling outage and is likely not to have any scheduled maintenance during its initial 15 months 7
of operation, this capacity factor assumption may not be unreasonable.
Alternatively, forced outages and repairs tend to be above average for an immature reactor. Assuming this to be the case, and to add conservatism to the staff's estimate, the staff assumes Limerick 2's forced outages will be about 30% above the national average for all nuclear reactors.
This translates to a 55% capacity factor over the 15 month timeframe. An indicaticn of the conservatism built into this number is reflected in the fact that from February 1986 to May 1987 (initial 15 months of operation)
Limerick Unit 1 operated at a 79.3% capacity factor.
In spite of this extremely strong performance by Limerick Unit 1, the staff chose to view this as only one data point and opted for a value more representative of an average reactor.
Modifying the NUREG/CR-4012 replacement energy cost estimate to reflect a 65% capacity factor and adjusting to 1989 dollars based on the GNP Implicit Price Deflator results in a daily penalty for Limerick 2 of just under $500,000. Assuming a loss of nuclear generation for 15 months results in a total cost penalty of $228 million [456 days X $500,000 per day].
For comparative purposes the staff notes that the Philadelphia Electric Company (PECo) has also estimated replacement energy cost penalties for l
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the Limerick 2 unit. E,E The replacement energy cost for relatively 1
.hort term outages (one to five months) associated with SAMDA l
l modifications made in the 1991-94 timeframe is estimated at $850,000 per day 1/ This estimate assumes 1991-94 dollars and an effective 100%
capacity factor for Limerick Unit 2.
Elsewhere, PEco estimates replacement energy costs for a Limerick Unit 2 delay in the 1990-91 timeframeat$11.9millionpermonth.El This estimate assumes a capacity factor on the order of 75%. These estimates result in total 2 placement er. orgy cost penalties of $214 million to $388 million vs. the staff's estimate of $228 million.
The staff is aware that during the delay period sizable interest (approximately $360 million per year) will accrue on the capital investment in Limerick 2.
The utility has identified these interest charges, in the form of Allowance for funds Used During Construction (AFUDC),asacostofdelay.El The staff's position is that although the delay in commercial availability may effect who ultimately covers the interest charges [ Stockholder vs. ratepayer] and the timing of their 5/
Bechtel Power Corporation, "SAMDA Estimate Process and Cost Estimate Breakdown - Limerick Generating Station for Philadelphia Electric Company, " July 27, 1989, PP 11, 49, 55.
6/
Affidavit of Corbin McNeil, Executive VP-Nuclehr, Philadelphia Electric Company Before the U.S. Nuclear Regulatory Commission, June 15, 1989.
7/
Bechtel, op. cit.
p/
McNeil, op. cit. p. 2.
9/
ibid.
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- recovery, the carrying charges on the debt are essentially a fixed cost that are independent of whether the reactor operates or not. Therefore, it'is not an incremental cost'of delay.
i.
In a somewhat similar vein, other costs may be incurred during the delay period such as secairity, maintenance, and operational costs. PEco has estimated these at $5.3 million per month. El :owever comparable costs 1
would also be incurred if the plant were operational, and therefore these costs teo should not be viewed as incremental costs of a delay.
Respectfpily submitted, kvin isb c Ovt.- -
Ann P. Hodgdon Ccunsel for NRC Staff Dated at Rockville, Maryland this 2nd day of. August, 1989 Le g / ibid.
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