ML20198K009
| ML20198K009 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 09/18/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20198J990 | List: |
| References | |
| NUDOCS 9812300321 | |
| Download: ML20198K009 (10) | |
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Wo vg 3* 4 UNITED STATES j j f
NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20066-0001 s
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION ON THE REQUEST FOR EXEMPTION FROM CERTAIN 10 CFR PART 50 REQUIREMENTS FOR EMERGENCY PLANNING FOR CONSUMERS ENERGY COMPANY BIG ROCK POINT NUCLEAR PLANT DOCKET NO. 50-155
- 1. INTRODUCTION By letter dated September 19,1997, as supplemented by letters dated October 29,1997, and March 2 and July 30,1998, Consumers Energy Company (the licensee) submitted a request for exemptioa from offsite and some onsite emergency planning requirements contained in 10 CFR 50.47 and Appendix E to 10 CFR Part 50. On August 30,1997, the licensee permanently shutdown the Big Rock Point Nuclear Plar' (BRP) and on September 20,1997, completed the removal of fuel from the reactor vessel.
- 2. MCKGROUND The NRC may grant exemptions from the requirements of its regulations which, pursuant to
._ 10 CFR 50.12(a), (1) are authorized by law, will not present an undue risk to the pui:N health l
} and safety and are consistent with the common defense and security, and (2) present special i circumstances. Sect,on 50.12(a)(2) of 10 CFR 50 identifies special circumstances to be l present, in part, Genever application of the regulation in the particular circumstances would
! not serve the underlying purpose of the rule or is not necessary to achieve the underlying j purpose of the rule, compliance would result in undue hardship or cost that are significantly in i excess of those incurred by others similarly situated, or circumstances exist that were not i
considered when the regulation was adopted for which it would be in the public interest to grant j an exemption.
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, in the licensee's submittals the following special circumstances were presented. BRP shut down on August 30,1997, and is now in a permanently shutdown and defueled condition. With l the plant in a permanently shutdown and defueled condition, the applicable design basis
- accidents are limited to a fuel handling incident and spent fuel cask drop. The licensee has also evaluated other radiological events such as a loss of spent fuel pool water level and
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cooling, fire involving radioactive resin, and the decommissioning events summarized in the i NRC's Generic Environmental Impact Statement for decommissioning facilities (NUREG-0586). j The calculated maximum offsite dose from these postulated releases is less than the U.S.
! Environmental Protection Agency (EPA) Protective Action Guides (PAGs). The licensee also j estimated that by April 6,1998, a beyond design basis event involving fuel damage (caused by i
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. 2 e i I a loss of spent fuel pool water and a subsaquent overheating of the stored fuel) and the release
- of radioactive materials sufficient to exceed EPA PAGs at the site boundary is not credible.
Once a radiological release warranting prompt offsite response is no longer possible, offsite
! response capability, including offsite emergency plans, would no longer be necessary. The
! licensee also stated, during a meeting open to public observation held at NRC Headquarters on August 13,1998, that requiring BRP to comply with the requirements for offsite emergency '
planning when it is no longer warranted would result in undue financial hardship to BRP, its owners, and their ratepayers.
- 3. DISCUSSION AND STAFF EVALUATION
.The staff's evaluation consists of two parts. The first part concerns the staff's review of the
, licensee's analysis of the radiological consequences from potential events involving radioactive j material. The second part concerns the staff's review of each of the specific emergency 4
- preparedness regulations from which the licensee requested to be exempted.
I 3.1 Radm!oaical Consecuences With the plant permanently shutdown and defueled, the design basis accidents and transients l postulated to occur during reactor operation are no longer possible. Specifically, the potential i for a forced release of a large radiological source term to the environment, due to the high pressure and temperature associated with reactor operation, is no longer possible. Additionally, a marked reduction in the radiological source term has occurred following final plant shut down i on August 29,1997, due to the radioactive decay of shor1 lived isotopes contained within the ,
spent fuel cladding. ,
! Revision 7 to the BRP Final Hazards Summary Report (FHSR) includes revised analyses of I postulated accidents at BRP in its permanently shutdown and defueled status. Chapters 9 and 15 of the FHSR describes the radiological consequences of accidents that could release radioactive materials, to the environment. !n particular, these chapters, in part, describe a loss of spent fuel pool cooling and level, cask drop, and fuel assembly drop. The staff reviewed ;
these FHSR analyses and the accidents and events evaluated in licensee letters dated l February 27,1995, November 20,1997, and April 29,1998, to determine whether the ,
! radiologicalimpact of these events would require an offsite emergency plan. ,
! 3.1.1 Heavy Load Droos onto Soent Fuel l
L The licensee considered a spectrum of potential accidents involving mechanical damage to spent fuelincluding:
e Single bundle damage during fuel handling e Damage to 22% of the core due to a drop of a heavy load into the pool .
- e Damage to all bundles from the last core offload l e Damage to all bundles in the pool due to a heavy load drop event a
The licensee's analysis (which did not give credit for containment isolation and used an atmospheric dispersion coefficient for a ground level release in accordance with Regulatory f .-
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Guide 1.25) showed that the offsite dose at the site boundary dropped below Environmental l
i Protection Agency (EPA) protection action guide (PAG) values of 1 Rem total effective dose
' equivalent (TEDE) and 5 Rem to the thyroid after the fuel had decayed for 63 days.
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I 3.1.2 Losa.of So' ent Fuel Pool Coolino i-
{ The licensee analyzed the heat up of the spent fuel pool which would occur upon a loss of
[ spent fuel pool cooling. The licensee determined that,93 days following shutdown, the spent j fuel pool temperature increase would not exceed 150 'F if a loss of spent fuel pool cooling occurred. The licensee states that 150 'F is the temperature below which the strength j! properties of the fuel pool concrete are not degraded. 3 i
! 3.1.3 Loss of Soent Fuel Pool Water Level The licensee also analyzed the potential for a loss of spent fuel pool water due to drainage from '
- 1. the pool. The spent fuel pool is a concrete structure which is lined with a 3/16 inch stainless
- steel plate. The spent fuel pool utilizes anti-siphoning makeup lirJ.ts and a weir discharge l system to maintain 23 feet of water over the active portion of the fuel. The potential for l accidental draining of the spent fuel pool which could cause zircaloy to react with steam was j evaluated as part of the Spent Fuel Pool Expansion Hearings in the early 1980's. This evaluation showed that accidental draining of the fuel pool was unlikely; however, to provide ,
j added assurance, the licensee installed additional makeup sources for the fuel pool. As part of f the hearings, the NRC evaluated the licensee's analysis and concluded that the reliability of the makeup system had been established based on the single failure criterion of Appendix A to 10 ,
CFR Part 50 and sound engineering practice (20 NRC 601). ,
The licensee analyzed the potential for a self-sustaining zircaloy oxidation if a complete loss of spent fuel pool water occurred. The licenses concluded that, as of April 6,1998, air cooling of spent fuel would be sufficient to maintain spent fuel clad temperature below 565'C, the temperature below which zircaloy cladding would not be subject to an incipient clad failure.
This cladding temperaW is below the expected cladding failure temperature of 671'C and the self-sustaining zircaloy oxidation temperature of about 900*C.
The Plant Systems Branch (SPLB) staff reviewed the licensee's calculations and determined that the heatup of the fuel would be greater for a scenario where the active fuel is totally uncovered and water blocks the assembly inlet so that no natural circulation flow path exists.
The staff calculated that, for this case, as of August 30,1998, it would take approximately 14 .
hours for the hottest location in the highest power assembly to reach 900'C. The heat up time was calculated assuming an adiabatic heat up of a fuel rod and using conservative decay heat assumptions. SPLB staff considers this scenario bounding for any loss of inventory scenario since any other scenario would have some heat removal from the assembly and a longer heat up time. Consequently, the staff determined that, in view of the low likelihood of the bounding scenario and the time elapsed since the shutdown of the facility, there would be sufficient time for mitigative actions and, if necessary, offsite measures after a postulated loss of water and before the spent fuel of the highest power assembly would heat up to 900'C.
In addition to the evaluation of the likelihood of an accidental draining of the spent fuel pool, the
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licensee evaluated two potential consequences of the complete draining of the spent fuel pool.
The two consequences evaluated are: (1) the radiological impact due to gamma rays emanating from the uncovered fuel rods, and (2) the potential for initiation of a rapid oxidation of the zircaloy cladding around the fuel rods.
The licensee calculated the offsite radiologicalimpact of a postulated complete loss of spent fuel pool water with the computer code Microskyshine. The fuel was modeled as a thin planer source to minimize self-shielding effects of the fuel. An assumed complete drain down of the ,
pool results in a dose rate of 0.046 mrem per hour at the closest site boundary, in the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that it is assumed needed to reestablish fuel pool water level, an individual at this location would only receive .0011 Rem, well within the EPA's early phase PAG of one Rem TEDE.
Microskyshine is a commercially available computer code, widely used in the radiation shielding industry, and is acceptable to the staff.
3.1.4 Non-Fuel Related Decommissionina Accidents
- The licensee evaluated potential non-fuel related decommissioning accidents including l explosions and fires, loss of contamination control, waste transportation accidents, external events and natural phenomena. The licensee's analysis showed that all postulated' i decommissioning accidents for the BRP plant are bounded by the results described in the l NRC's Generic Environmental Impact Statement on decommissioning of nuclear facilities l (NUREG-0586) which found that radiation doses to the maximally-exposed individual from an !
accidental airborne release of radioactive material during decommissioning were low.
Decontamination of systems during decommissioning and dismantlement operations is ,
expected to generate significant radioactive waste in the form of contaminated domineralizer !
resins. The worse case event that would provide a motive force for the release and transport of airborne radioactivity offsite is a fire in a fully loaded resin liner. Resins are collected and de-watered in liners onsite prior to transporting offsite for disposal. Using a release fraction of 1%,
and current design basis meteorology, the licensee calculated a fire in a resin liner loaded with
- the maximum activity allowed, would result in a maximum offsite dose of .096 Rem TEDE. The i release fraction is consistent with the release fractions listed in Schedule C to 10 CFR 30.72, ,
- for mixed fission and corrosion products. The calculational methods and assumptions used in j this analysis are acceptable to the staff.
The staff has determined from review of the licensee's analysis that the postulated dose to the
, general public from any reasonably conceivable accident would not exceed EPA PAG levels
' and, for the bounding accident, the length of time available provides confidence that mitigative actions and, if necessary, offsite measures for the public could be taken, without preplanning. ,
g Therefore, the staff concludes that it is acceptable to exempt the licensee from those ;
emergency preparedness requirements for responding to events involving the release of i radioactive material in which would result in offsite doses in excess of the EPA PAGs.
t 3.2 Evaluation of Emeraency Plan Exemotions Under $50.54(q), a licensee authorized to possess and operate a nuclear power reactor shall follow and maintain in effect both onsite and offsite emergency plans which meet the standards r
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5 in $50.47(b) and the requirements in Appendix E to 10 CFR Part 50. The licensee requested to :
L be exempted from some of the standards in $50.47(b) and the requirements in Appendix E to
- 10 CFR Part 50 that relate to response to events involving the release of radioactive material :
t which would result in offsite dose in excess of the EPA PAGs. The staff's evaluation of each of
- the requested exemptions is described below. !
j 10 CFR 50.47(b)(3) i I -. The licensee requested eliminating the arrangement to accommodate State and local staff at a near site emergency operation facility. The emergency plan would continue to maintain arrangements for requesting and using assistance resources from other organizations.
The staff found this change acceptable.
The licensee requested exemption from the need for State and local plans to rely on information provided by the licensee for offsite response measures.
The staff found this change acceptable.
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- 10 CFR 50.47(bMS)
. The licensee requested exemption from the need for establishing procedures and means for notification of the public within the emergency planning zone (EPZ).
, The staff found this change acceptable. .
1 10 CFR 50.47(bM6) 4 i The licensee requested exemption from the need for the provision of prompt communications 2 with the public.
The staff found this change acceptable.
l 10 CFR 50.47(bV7) 1 i The licensee requested exempt.on from the need for providing information to the public on a periodic basis concerning initial actions in an emergency, and a physical location for the
- dissemination of information to the news media.
j The staff found this change acceptable.
10 CFR 50.47(bV91 :
- The licensee requested an exemption from the requirement to have the capability to assess and monitor specifically "offsite" consequences of radiological emergency conditions.
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The licensee's exemption request is based on the conclusion that no design basis accident or ,
j - credible beyond design basis accident can result in radioactive releases which exceed EPA !
PAGs at the site boundary. The bounding accident assessed by the staff was & low likelihood event that resulted in postulated doses in excess of EPA PAGs. However, the length of time 1- available provides confidence that offsite measures for the public could be taken without preplanning. In Section 10.2, " Assessment Methods," of the licensee's draft Defueled ,
Emergency Plan, the licensee states the following:
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" Radiological release assessments are performed using measured radiological and
- meteorological data. Dose assessment graphs are initially used by the Site Emergency
- Director or other trained emergency response personnel to determine the industrial area dose rate.
Additional assessments of potential radiation dose to plant personnel from direct radiation or potential exposure from various other sources will be performed as appropriate."
The licensee has committed to revise this section of its emergency plan to .specify that it will have the capability to determine the potential impact of a radiological emergency to the general
! public. This information would be used to determine whether offsite measures for the general
> public would be appropriate. The staff found this change acceptable on the basis of the l 4
licensee's commitment to maintain the capability to determine the potential impact of a radiological emergency to the general public.
10 CFR 50.47(b)(10) i The licensee requested exemption from the requirement to develop protective actions for the )
plume exposure and ingestion pathway EPZs. l i
j The staff found this change acceptable.
I 10 CFR 50 Anoendix E IV i !
The licensee requested exemption from the requirement to provide an analysis of the time i required to evacuate and take other protective actions offsite. ,
- The staff found this change acceptable.
i 10 CFR 50 Aooendix E IV A.3.
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The licensee requested exemption from the requirement to describe licensee headquarters personnel who will be sent to the plant site in an emergency.
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- The staff found this change acceptable.
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10 CFR 50 Accendix E IV A.4.
The licensee requested an exemption in order to eliminate the term "offsite" in relation to dose :
projections that will be performed.
The licensee's exemption request is based on the conclusion that no design basis accident or credible beyond design basis accident csn result in radioactive releases which exceed EPA .
PAGs at the site boundary. The bounding accident assessed by the staff was a low likelihood event that resulted in postulated doses in excess of EPA PAGs. However, the length of time available provides confidence that offsite measures for the public could be taken without preplanning. In Section 10.2, " Assessment Methods," of the licensee's draft Defueled Emergency Plan, the licensee states the following:
" Radiological release assessments are performed using measured radiological and meteorological data. Dose assessment graphs are initially used by the Site Emergency Director or other trained emergency response personnel to determine the industrial area dose rate.
Additional assessments of potential radiation dose to plant personnel from direct radiation or potential exposure from various other sources will be performed as appropriate."
The licensee has committed to revise this section of its emergency plan to specify that it will have the capability to determine the potential impact of a radiological emergency to the general public. This information would be used to determine whether offsite measures for the general public would be appropriate. The staff found this change acceptable on the basis of the licensee's commitment to maintain the capability to determine the potentialimpact of a radiological emergency to the general public.
_10 CFR 50 Accendix E IV A.S.
The licensee requested exemption from the requirement to identify individuals with special qualifications.
The staff found this change acceptable.
10 CFR 50 Aooendix E IV A.8.
The licensee requested exemption from the requirement to identify State and local officials responsible for protective actions.
The staff found this change acceptable.
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8 10 CFR 50 Accendix E IV B.
The licensee requested exemption from the requirement to base emergency action levels on offsite monitoring results and consideration of protective measures outside the site boundary.
The staff found this change acceptable.
10 CFR 50 Accendix E IV C.
The licensee requested axemption from the requirement to base emergency action levels on offsite radiological monitoring information and information from other sensors, such as containment pressure, that are no longer appropriate. The licensee requested to eliminate emergency classification above the Alert level.
The staff found this change acceptable.
10 CFR 50 Accendix E IV D 1.
The licensee requested exemption from the requirement for administrative and physical means for the prompt notification of the public of protective measures.
The staff found this change acceptable.
10 CFR 50 Accendix E IV D 2.
The licensee requested exemption from the requirement for yearly dissemination of emergency planning information to the public.
The staff found this change acceptable.
10 CFR 50 Accendix E IV D.3.
The licensee requested exemption from the requirement to demonstrate that State / local officials have the capability to make public notification promptly, and changed the time for notification of State and local agencies to within 30 minutes after declaring an emergency.
The staff found this change acceptable.
10 CFR 50 Anoendix E IV E.8.
The licensee requested exemption from the requirement to provide for a near site emergency operations facility.
The staff found this change acceptable.
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- . 9 l 10 CFR 50 Anoendix E IV E.9.a. j i The licensee requested elimination of the term "within the plume exposure pathway EPZ" from the description of communication systems with State / local govemments. '
The staff found this change acceptable.
, 10 CFR 50 Anoendix E IV E.9.c.
l The licensee requested exemption from the requirements for provision of communications j among the near site emergency operations facility, the nuclear facility, state and local ;
- emergency operations centers and field assesement teams.
7 The staff found this change acceptable.
l 10 CFR 50 Anoendix E IV E.9.d.
- The licensee requested exemption from the requirements for provision of communications by ,
- the licensee from the onsite technical support center and near site emergency operations
- facility to the NRC Headquarters and Regional Operations Center. The licensee will maintain
! provision for these communications from the control room, and changed the frequency of test of i such communications to quarterly.
! The staff found this change acceptable.
10 CFR 50 Aooendix E IV F.1 The licensee requested to delete local news media persons from the list of categories of
, emergency personnel provided periodic training.
The staff found this change acceptable. ,
l 10 CFR 50 Anoendix E IV F.2. -1 l
The licensee requested to eliminate the requirement to test the public notification system as l part of emergency preparedness exercises. l The staff found this change acceptable.
i 10 CFR 50 Anoendix E IV F.2.c.
l The licensee requested exemption from the requirement for a biennial exercise with full l participation of offsite authorities.
The staff found this change acceptable. !
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. 10 10 CFR 50 Anoendix E IV F.2.d.
The licensee requested exemption from the requirement for an ingestion pathway exercise.
The staff found this change acceptable.
10 CFR 50 Anoendix E IV F.2.e.
i The licensee requested to modify the language of this section by deleting the phrase ' located within the plume exposure pathway EPZ," and adding the word " contiguous" to clarify the governmental entities who would be permitted to participate in emergency preparedness drills.
The staff found this change acceptable.
10 CFR 50 Accendix E IV F 2.f.
The licensee requested to eliminate the requirement to perform remedial exercises.
The staff found this change acceptable.
4.0 CONCLUSION
S The staff concludes that the licensee's request for an exemption from certain requirements of 10 CFR 50.47(b), and Appendix E to 10 CFR Part 50 is acceptable in view of the greatly reduced offsite radiological consequences associated with the current plant status. The staff finds that the postulated dose to the general public from any reasonably conceivable accident would not exceed the EPA PAG dose levels and, for the bounding accident, the length of time available provides confidence that mitigative actions and, if necessary, offsite measures for the public could be taken, without preplanning. The approval of the requested exemptions from 10 CRF 50.47(b)(9) and Section IV.E.A.4 of Appendix E to 10 CFR Part 50 is contingent upon the licensee implementing its commitment to revise its emergency plan to specify it will maintain the capability to determine the potential impact of a radiological emergency to the general public.
Principal Contributors: James B. O'Brien Roger L. Pedersen
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