DD-87-21, Director'S Decision DD-87-21 Denying Addl Relief Requested by Petitioners That Commission Order Immediate Implementation of Relief Noted in 860506 Petition Re Suspension of Further Licensing of Nuclear Plants in Us
| ML20195G912 | |
| Person / Time | |
|---|---|
| Issue date: | 12/15/1987 |
| From: | Murley T Office of Nuclear Reactor Regulation |
| To: | GOVERNMENT ACCOUNTABILITY PROJECT |
| Shared Package | |
| ML19313A417 | List: |
| References | |
| RTR-NUREG-1250, RTR-NUREG-1251 2.206, DD-87-21, NUDOCS 8712240113 | |
| Download: ML20195G912 (18) | |
Text
DD-87-2A
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' UNITED STATES OF AMERICA NUCLEAR REGULATCRY Co MISSION
'g7 gC 16 P3 :54 0FFICE OF NUCLEAR REACTOR REGULATION f a H . ,. a ,_ ,
Thomas E. Murley, Director QIffyg;:fi<vicr '
In the Matter of )
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Potential Inplications of ) (10 C.F.R. 2.206)
Chernobyl Accident for All )
NRC Licensed Facilities )
INTRODUCTION By letter to the Director of the Office of Nuclear Reactor Regulation dated May 1, 1987 (Petition) Thomas Carpenter, on behalf of Government Accountability Project (GAP) and others (together, Petitioners), requested that the Comission order immediate implementation of the relief that the ;
Petitioners had requested in a petition filed on May 6, 1986 as a result of the April 25, 1986, accident at the Chernobyl power station in the Ukraine, U.S.S.R. The action requested in the May 6, 1986 petition was that the NRC [
(1) suspend further licensing of nuclear facilities in the United States pending completion of a study and report on the accident at the Chernobyl plant, (2) review the findings of the final report for their applicability to facilities licensed by the NRC, and (3) request pubite conenents on whether the record should be reopened to consider new issues raised in the final report I
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t t n 2-that are material to any pending licensing proceeding or current license. V The present Petition essentially requests the same relief. This Petition, which is supported by an enclosuro entitled, "Memorandum of Points and Authorities in Suppcrt of Chernobyl Petition," asserts that there is a similarity between the Chernobyl reactor and boiling water plants in the United States. Furthermore, the Petition maintains that the Chernobyl accident provides important experience
.that warrants a review of existing industry standards under NRC regulations.
By letter dated June 8,1987, the Petitioners were informed that imediate implementation of their requests was not warranted, but that their Petition would be treated under 10 C.F.R. % 2.206 of the Comission's regulations and that action would be taken on their requests within a reasonable time.
I have now completed my evaluation of the matters raised by the Petitioners.
As discussed below, the staff has corrpleted a study and prepared a final report of the Chernobyl accident and reviewed the findings of the final report for their applicability to currently licensed facilities or facilities under construction.
Thus, to the extent that the Petition requests that the staff undertake such a study and review, those requests have, in effect, already been granted. For the reasons discussed below, the additional relief requested by the Petitioners is l
! denied.
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- The May 6, 1986 petition was denied by letter dated May 27, 1986. The l
dental was based upon the Petitioners' failure to provide specific information which would compel a halt to licensing of facilities in the United States.
1 DISCUSSION i l
I. I The Petitioners request that the NRC (1) initiate all currently available legal options to learn as expeditiously as possible all material facts concerning the Soviet accident; (2) prepare and make publicly available ongoing analyses of the relevance of this information to NRC-licensed facilities; (3) prepare a final, published report of these findings; (4) review the findings of the final report to determine the safety consequences with respect to licensed facilities operating or under construction in the United States; and (5) suspend the granting of operating licenses for facilities under construction in the United States until the final report is completed.
Immediately upon learning of the event at the Chernobyl plant in the Soviet Union, the NRC formed a task force to evaluate thoroughly the accident and to learn as much as possible about its causes, course, and consequences. The results of this effort, including a detailed account of the accident progression at Chernobyl, were published in January 1987 in NUREG-1250, "Report on the Accident at the Chernobyl Nuclear Power Station," which was prepared collaboratively by the NRC, other United States Government agencies, and other groups. ;
The NRC also has issued for public comment a draft report entitled, "Implications of the Accident at Chernobyl for Safety Regulation of Commercial Nuclear Power Plants in the United States" (NUREG-1251, August 1987). NUREG-1251
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assesses the implications of the Chernobyl accident with respect to a number of reactor safety regulatory issues associated with significant factors that led to or exacerbated the consequences of the Chernobyl accident. These issues include the areas of administrative controls and operational practice, design, containment, emergency planning, severe-accident' phenomena, and graphite-
. moderated reactors.
The causes of the accident at Chernobyl are documented and discussed in detail in NUREG-1250. As set forth therein, although the Chernobyl accident was initiated by serious operator violations of safety procedures, the ensuing reactor damage stenned from basic design features of the RBMK 1000 reactor.
The design of reactors in the United States specifically precludes the type of
! damage that occurred at Chernobyl. The RBMK reactor design does not use large steel reactor pressure vessels with water as a moderator, such as are employed in the designs of reactors in the United States. Rather, the RBMK uses a graphite-moderated pressure tube concept, which, in some conditions or modes of operation, has an undesirable characteristic known as a positive void coefficient.
A positive void coefficient means that rapid power increases, leading to vaporization of cooling water in the pressure tubes, will produce further power
- increases. This condition is extremely difficult to control. At Chernobyl, this condition developed so quickly that the operators and automatic safety systems had no opportunity to respond, and an explosion resulted. In addition, before the event, some safety systems had been deactivated and a number of t
operating procedures were violated. Moreover, the slow-acting safety control 1
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rod system of the RBMK design further contributed to the event, which was exacerbated still further by the ensuing graphite fire.
In the United States, as comercial nuclear power was being developed, the importance of control stability and negative void and negative power coefficients was explicitly recognized. As documented in NUREG-1251, the nuclear cores of commercial reactors in the United States are designed specifically to prevent the power instability that caused the Chernobyl accident. Unlike the Chernobyl reactor, the cores in reactors in the United States are equipped with fast-acting safety control rod systems. Thus, because of the physics inherent in their design, reactors in the United States respond to an increase in voiding by reducing power.
Notwithstanding important design differences between the Chernobyl reactor and comercial reactors in the United States, the findings from NUREG-1250 and ,
NUREG-1251 have added to our understanding of some of the phenomena that may be involved in a severe nuclear accident, and they have provided some additional insights that are useful in guiding our severe-accident programs. The overall conclusion of the staff regarding the implications of the Chernobyl accident for the safety regulation of comercial nuclear power plants in the United States is stated in NUREG-1251 as follows:
ho imediate changes are needed in the NRC's regulations regarding the design or cperation of U.S. comercial nuclear reactors. Nuclear design, shutdown margin, containment, and operational controls at U.S. reactors protect them against a combination of lapses such as those experienced at Chernobyl. Although the NRC has always acknowledged the possibility of major accidents, its regulatory requirements provide adequate protection against the risks, subject
to continuing vigilance for any new information that may suggest particular weaknesses, and also subject to taking measures to secure compliance with the requirements. Assessments in the light of Chernobyl have indicated that the causes of the accident have been largely anticipated and accenrnodated for comercial U.S.
reactor designs.
Thus, the staff's actions have essentially satisfied the requests in the Petition that the NRC (1) study and prepare a report of the accident and (2) review the findings of the report for applicability to currently licensed facilities. With respect to the Petitioners' request that the NRC suspend the granting of optrating licenses for facilities under construction until completion of the final report, this request is denied. As discussed above, the steam explosion in the reactor core, which ruptured the reactor core and the surrounding building, was caused by a nuclear physics design vulnerability specific to the RBMK reactor. On that basis and because of other factors discussed above, I find that the contention of the Petitioners concerning the suspension of the granting of operating licenses to facilities under construction is without merit.
II.
The Petitiorers further request that the NRC request public coments on whether the "record" should be opened to consider "new issues" raised in the final report on Chernobyl that are material to any pending licensing proceeding.
In general, the Petitioners argue that, following the accident at Three Mile Island, the Comission estab21shed a precedent that mandates a review of existing industry standards whenever an event within the industry provides
"important. industry experience." The Petitioners assert that the Chernobyl accident meets the requirement of "important industry experience" necessary for a review of Comission and industry standards. Hence, the Petitioners claim that the Comission must take the same initiative in response to the Chernobyl incident that it did in reviewing its regulations following the accident at Three Mile Island, and that a failure to do so, absent a full explanation, would constitute "arbitrary and capricious behavior" prohibited by the Administrative Procedure Act.
As discussed in the preceding paragraphs, the NRC did respond imediately to the accident at Chernobyl by forming a task force and coordinating a major fact-finding effort. The NRC's comitment to identify the lessons learned from the Chernobyl accident and determine their relevance to facilities in the United States and existing industry standards is evidenced by the publication of draft NUREG-1251, "Implications of the Accident at Chernobyl for Safety Regulation of Comercial Nuclear Power Plants in the United States." After all comments received during the public coment period are duly considered, a final report will be issued.
The basic design differences between the RBMK reactor at Chernobyl and reactors in the United States had a direct bearing on the NRC's response to the accident at Chernobyl. The accident at Chernobyl was a highly energetic reactivity excursion that mechanically disrupted the core. Fragmented fuel that came into contact with water rapidly vaporized the water. This generated combustible hydrogen by the chemical reaction of core materials and water at the high temperatures reached in the accident. Because of the basic design i
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l differences between the RBMK reactor at Chernobyl and reactors in the United States, the specific accident mechanisms involved at Chernobyl have no exact parallel in reactors in the United States. Within days of the accident at Chernobyl, it was recognized that the inherent vulnerabilities in the RBit design were not present in comercial reactor design in the United States.
Therefore, it was determined that imediate regulatory action was not warranted.
~However, as a precaution, it was deemed that the most prudent course of action was to undertake an intensive effort to understand the accident phenomenology and to assess U.S. power plant design and operational practices in light of the factors that led to and exacerbated the accident at Chernobyl. NUREG-1251 provides this assessment.
The Petitioners specifically identify three basic areas that they allege constitute "industry weaknesses," for which they claim consideration and revision of existing standards are warranted. Broadly stated, these areas involve (1) containment structures, (2) operator training, and (3) emergency planning. The Petitioners also state that consideration and revision of st?ndards need not be limited to these areas.
With regard to containment, the Petitioners argue that the containment used at Chernobyl was the type comonly employed at many boiling water reactors in the United States, and that the Chernobyl accident, in light of this similarity, creates new "industry experience" that must be considered < / the Comission.
- In this connection, the Petitioners call for (1) a complete review of all containment structures at both completed plants and those under construction.
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in order to provide a uniform, complete standard of adequacy for all plants and (2) a public forum en the contair, ment standard proposed by the NRC.
Because the accident phenomenology at Chernobyl was unique to the RBMK design, it is impossible to directly compare how reactor containments in the United States would survive an accident similar to that at Chernobyl. However, the role of the containment building as a vital barrier to the release of fission products to the environment has been recognized for some time in power plant design and regulation in the United States. The NRC began to give attention to severe accidents even before the accident at Three Mile Island and has increased its emphasis in this area since that accident. The Chernobyl accident focused new attention on containments and their performance under severe-accident conditions. Thus, design differences notwithstanding, the implications of the Chernobyl accident were evaluated with respect to containment design and performance.
Specifically, the staff evaluated the implications of the accident at Chernobyl with respect to activities already in place in the areas of l
, containment integrity and the ability to prevent the release of large quantities of fission products during severe accidents. In its assessment of the impact of the Chernobyl experience on current programs addressing centsinment adequacy (NUREG-1251, Chapter 3), the staff concludes that ongoing research programs and regulatory initiatives are adequate to identify and implement the design and operational improvements needed to provide greater assurance of containment survival in severe accidents. These programs under way include the systematic search for plant-specific vulnerabilities in l
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containment structures and performance to be achieved through the implementation of the Comission's Severe Accident Policy. Section 3.1.1 of huREG-1251 provides a brief sumary of the basis and purpose of the Comission's Severe Accident Policy:
Severe-accident evaluations and research had progressed to the point that the Comission issued a Severe Accident Policy Statement in August 1985 (50 FR 32138) concluding that existing plants posed no undue rTsk to the public.
However, the Comission pointed out that at each plant there will be systems, components, or procedures that are the most significant contributors to risk. Utilities should identify these contributors and develop approsriate courses of action, if and as needed to ensure acceptable margins of safety. Furthermore, the Comission stated that such examinations "will include specific attention to containment performance in striking a balance between accident prevention and consequence mitigation."
Implementation of the Severe Accident Policy Statement through the Individual Plant Examinations (IPEs), utilizing emerging research, is expected to indicate whether risk outliers exist at specific plants that justify improvements in containment system performance. This implementation is the principal NRC program for identifying plant-specific severe-accident risk outliers and for implementing new requirements. Other ongoing programs and initiatives that address the adequacy of containment designs are described in more detail in Section 3.1.2 of NUREG-1251. Inasmuch as the implementation of the Comission's Severe Accident Policy will require the review of containments for all plants, the Petitioners' request for review of containment structures has been granted.
With regard to operator training, the Petitioners argue that the existing NRC regulations governing the establishment of training programs as set forth r
11 in 10 C.F.R. Part 50, Appendices E and F, do not provide for monitoring operator training or the individuals who will provide such training. Asserting that Chernobyl provides important "industry experience" in this area, the Petitioners claim that current regulations must be revised to provide for such monitoring.
Contrary to the Petitioners' assertion, 10 C.F.R. Part 50, Appendix E.
Section F requires initial training, periodic retraining, and exercises to test the adequacy of training for control room shift personnel to ensure their familiarity with emergency response plans and duties. The adequacy of this training is evaluated by NRC through inspections and exercise evaluations.
With regard to training received by operators in the use of and adherence to operating procedures, Chapter 1 of NUREG-1251 describes and assesses the adequacy of administrative centrols and operational practices for reactors in the United States. Section 1.1.1 provides details of NRC requirements and guidance for procedures development and use, required procedure coverage, standards, and NRC inspection and enforcement in these areas:
I The NRC has a large body of guidance and requirements that includes general and specific measures for development and use of adelnistrative procedures and controls. These controls govern all operating activities at nuclear pcwer plants, and are designed to avoid the types of violations that occurred at Chernobyl. Procedures are violated in licensed plants, but only rarely with the knowledge that a violation is being committed. In its program to ensure safety and quality, the NRC has developed and published quality assurance requirerents for activities affecting nuclear safety. Criterion V of 10 CFR 50 Appendix B, "Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants,"... prescribes the general requirement for having procedures and for following them, A second level of administrative controls for procedures
P y t is contained in each slant's Technical Specifications (TS),
which are a part of tie license.... Both Technical Specifications
- and Criterion V have the force of law.
Technical Specifications require procedures to be reviewed by
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the Unit Review Group when initially written and before being i changed, except for temporary changes made on the spot that do not alter the intent. The Unit Review Group is made up of key j
( plant supervisory personnel who are knowledgeable about plcnt 1 g safety. The objective of this review is to ensure that exparts
- - from the various technical disciplines review the procedures for
[ operations or changes that could affect safety. This review J
!! backs up the technical procedure writer and his/her supervisor's
( decisions on safety. There is a further screening of procedures and changes to procedures to determine whether or not they may C involve an unreviewed safety question or technical specification, ..
- in which case prior NRC approval is required by 10 CFR 50.59.
L The NRC requires that all of these activities, including h r compliance with procedures, be periodically audited, and audit 5 results be provided to appropriate management; corrective action E is required when deficiencies are found.
1 Additionally, reactor operators must be licensed by the NRC. Because plant h operation requires extensive use of procedures, operators are trained in ;
both the technical details of procedures and in their implementation. NRC !
{ examines operators in these areas in accordance with 10 C.F.R Part 55.
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In view of the fact that the Cocinission's existing regulations provide
- for operator training, an assessment of the adequacy of the training, and an .
[ examination of operators themselves, I find the Petitioners' contention that.
5 in light of Chernobyl, regulations must be revised to provide for monitoring of .
operator training, to be without merit.
Finally, with regard to erergency planning, the Petitioners argue that reevaluation of HRC standards for individual emergency plans is necessary to incorporate lessons learned from Cl'.rnobyl. The Petitioners claim that at p
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Chernobyl, even with well established emergency and evacuation procedures, J coordination with local officials hindered the effectiveness of emergency l
efforts. The Petitioners allege that Chernobyl provides important "incustry ,
experience" in this area and provides the greatest amount of data available l against which existing emergency and evacuation plans can be compared. Thus, !
the Petitioners argue that the Comission must provide a comprehensive plan i for review of emergency procedures currently in place at existing facilities.
The Petitioners also request that the Commission provide a detailed plan for coordination between owners, the NRC, and the State officia's during emergency situations and for the sharing of critical data on plant operation during the !
emergency. The Petitioners also request that the Cosuiission provide a public forum on a detailed plan to be submitted by tha NRC on evacuation, on a state-by-state basis, that will provide an overall strategy for evacuation based on individual plant design parameters.
I i The Petitioners did not support their claim that coordination with t local officials hindered the effectiveness of emergency efforts at Cl.ernobyl.
lI L Further, the Petitioners did not establish a relationship between Soviet :
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j emergency planning and U.S. emergency planning, nor do they establish a ;
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relationship between Soviet emergency response at Chernobyl and a possible f t
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] U.S. response during a domestic accident. In addition, it should be noted !
that the NRC has reviewed the Soviet emergency response to the Chernobyl i accident for implications for U.S. emergency planning and did not identify l e
j j issues that would support the Petitioners' recomendations in this regard.
- Section 7.2 of NUREG-1250 states that initially, Soviet emergency response was [
4 hindered by a lack of adequate equipment and facilities and an underestimation
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14 of the severity of the accident by plant personnel and local officials. However, these did not prevent a massive and apparently effective response by the Soviets.
NUREG-1250 also indicates that the delays in evacuation were dictated by local radiological conditions and logistics:
The available inf>rmation indicates that Soviet protective actions during the Chernobyl emergency consisted of sheltering, administration of KI, evacuation, decontamination, and measures to prevent radiation exposure in the ingestion pathway.
Ths decision to shelter the residents of Pripyat rather than to evacuate them on the day of the accident was based on the permissible levels of radiation measured in Pripyat, while at the same time high levels were measured along potential evacuation routes.
Evacuation of Pripyat did not comence until about 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> after the accident at Chernobyl because of this delayed increase in radiation levels at Pripyat and the need for coordinating the needed logistical resources, and preparing evacuation routes. Ad hoc evacuationcould arrangements" plansbehad to beINSAG, applied p(repared since 1986, not aljj"existing
- p. 78). Arrange-ments for transportation, setting up relocation centers, prov ding radiation monitoring and decontamination services for people, providing replacement clothing and other necessities, identifying and augmenting medical facilities, are some of the things that had to be done in order to carry out an effective evacuation.
i These actions were planned and put into place during the roughly 36hoursfromthetimeoftheaccidyttothestartofthe evacuation (Sanders, 1986, pp.3-4). Time was also needed to i take precautions along the evacuation routes that had been contaminated above permissible levels. This was done by using a polyner substance to cover land areas agng the roads used for the evacuation (Sanders, 1986, p. 4) l V International Nuclear Safety Advisory Group (INSAG), "Sumary Report on l the Post-Accident Review Meeting on the Chernobyl Accident," August 30 -
September 5, 1986, GLC (SPL.I)/3, IAEA, Vienna September 24, 1986.
2/ Sanders, Marshall, Federal Emergency Management Agency, testimony prepared for the U.S. Senate Subcomittee on Nuclear Regulation of the Comittee on Environment 61 and Public Works (hearing cancelled), September 29, 1986, I Washington, D.C.
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Ibid., p.t.
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In comparing the United States and Soviet programs, NUREG-1251 cautions that there is a substantial difference in the emergency planning base between j the United States and the Soviet Union. Specifically, NUREG-1231 states that
! after the accident at Three Mile Island, large resources were expended to improve emergency planning and response capabilities around plants in the United h States. The report also states that, in contrast, there is little indication that the Soviets have comparable site-specific emergency plans for the general 4
public around their nuclear power plants. The report further cautions that economic and societal differences play a part. Fcr example, in the United States, most people have access to private transportation and necessary alternative transportation is preplanned around nuclear pcwer plants.
NUREG-1250 notes that the dimensions of the Soviet response and the utility of the Soviet planning were dictated by the magnitude of the accident at Chernoby1:
l Similarly, the Russian delegation also stated... that when the
- response team from Moscow and other locations arrived at Chernobyl, it found the response plans had only limited value and t teamhadtoresortto"adhoc"planning (Sanders,1986).htthe The massive scale of the accident probably was a major factor in
! forcing ad hoc planning, as it was noted to have overwhelmed l local resources. This was because the release of several million
- curiesinitiallywithsimilarthoughsmallerreleasesdgflywas Warman, not included in Soviet preplanning (INSAG, 1986, p. 79; l
i V See footnote 2/ on pg.13.
5/ I See footnote on pg. 13.
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.l 1986a, p. 3).6/ For example, a c4jor difficulty was that, because ofthe"actualsituation...notpilexistingarrangementscouldbe l applied" (INSAG, 1986, p. 78).7 l 1
l As NUREG-1251 points out, specifics of the Chernobyl release are unique to the RBMK design. The amounts of radioactive material released from plants in the United States would, for most accident sequences, be considerably less because, among other things, plants in the United States have substantial containneents.
In addition, although low-probability, fast-moving accident sequences are possible, severe accidents at plants in the United States would, in general, progress more slowly, resulting in longer warning times before radioactive material would be released.
I NUREG-1251 notes that the NRC did not find any apparent deficiency in :
emergency plans and preparedness in the United States, including the 10-mile plume exposure pathway EPZ (emergency planning zone) size and the 50-mile L
, ingestion exposure pathway EPZ size. NUREG-1251 concludes that these zones t provide an adequate basis to plan and carry out the full range of protective actions for the populations within these zones, as well as beyond them, if the l
need should arise. However, NUREG-1251 does not.e that the planning bases for a t relocation and decontamination and for protective measures for the food ,
ingestion pathway are being reexamined in the light of new research information.
U Warman, Edward A., Senior Consulting Engineer, Stone and Webster Engineering Corporation,liotes of Private Discussions With Soviet -
Delegates at Vienna Meeting, September 5, 1986.
7/ See footnote II on pg. 13.
. l Regarding the Petitioners' reconenendations, the Petitioners fail to establish a nexus between the alleged weaknesses in the Soviet emergency i response to the accident at Chernobyl and U.S. emergency planning and i
preparedness for nuclear power plants. The Petitioners fail to show that l
their recommendations for review of U.S. planning are warranted by the Soviet experience at Chernobyl. Further, the U.S.'s own review of the Soviet response
.at Chernobyl, and its review of implications for U.S. emergency planning and preparedness, still in draft form, do not support the Petitioners' reconsnendations.
CONCLUSION As discussed above, the NRC has already extensively studied the accident that occurred at the Chernobyl facility and the implications of the accident i on facilities in the United States. The NRC has completed and published for I
comment a factual report (NUREG-1250) on the events of Chernobyl and a draft report (NUREG-1251) on the issue of the implications of the Chernobyl accident.
l Therefore, to the extent that the Petition requests that the NRC initiate all currently available legal options to learn the material facts concerning the l
! Chernobyl accident, prepare analyses of the relevance of this information for NRC-licensed facilities, and prepare a final published report of findings on this issue and review these findings to determine the safety consequences with i
! respect to facilities operating or under construction, those requests are, in l
effect, granted. For the reasons stated above, the additional relief l
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requested by the Petitioners is not warranted and is denied. As provided in 10 C.F.R. $ 2.206(c), a copy of this decision will be filed with the Secretary for the Comission's review.
FOR THE NUCLEAR REGULATORY COM11SS10N (f'% S --
Thomas E. Murley, Director Office of Nuclear Reactor Regulation Dated at Bethesda, Maryland, this 15th day of December 1987