ML19309H418
| ML19309H418 | |
| Person / Time | |
|---|---|
| Issue date: | 04/04/1980 |
| From: | Hendrie J NRC COMMISSION (OCM) |
| To: | Stafford R SENATE |
| References | |
| NUDOCS 8005130190 | |
| Download: ML19309H418 (11) | |
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UNITED STATES P\\
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80 0513 0 /TO WASHINGTON, D.C. 20555 Q5; Vl
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April 4,1980 OFFICE OF THE COMMISSIONE R The Honorable Robert T. Stafford United States Senate Washington, D.C.
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Dear Senator Stafford:
I am pleased to respond to the questions we discussed during the Committee on Environment and Public Works Hearing on February 28, 1980.
I trust they are fully responsive to your concerns.
In the event that you require any additional information, please do not hesitate to call me.
Sincerely, eph M. Hendrie Commissioner
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1.
"!!culd you please explain your reasons for originally withholding from public disclosure certain portions of your September 25, 1972 note to Mr. O' Leary regarding Dr. Hanauer's September 20, 1972 memorandum on pressure suppression containments?"
portions of my September 25, 1972 note to Mr. O' Leary regarding Dr.
Hanauer's September.20, 1972 memorandum on pressure suppression containments were originally'wlthheld on the basis of Exemption 5 of the Freedom of Information Act.
Exemption 5 specifies as exempt from release predecisional advice, opinions, and recommendations of the staff.
In general, these items constitute internal communications that would not ordinarily be available to a party in litigation with the agency.
The basis of the exemption is to encourage among staff groups a free and vigorous exchange of opinion and predecisional ideas and advice of the sort that might be inhibited if disclosure was automatic.
The hP regulations recognize, however, that the Freedom of Information Act is primily a disclosure statute and not a withholding statute.
To withhold documents, our regulations provide, in 10 CFR 9.9, that in addition to finding that the information is legally withholdable we must find that production or disclosure is contrary to the public interest or will adversely affect the rights of any person.
In making this determination the staff considers a variety of factors, including whether there is a compelling public need for the material, the age of the document, and
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the effect its release may have on future decision-making of the agency.
Two years ago, when the Freedom of Information Act request and draft answer came up to.me for approval, the staff, consistent with its previous practice in the use of Exemption 5, had recommended several deletions from my note.
My concern in reviewing the recommendation was whether those deletions met the test of Exemption 5.
Finding that they did, I approved the deletions.
2.
"Following an exchange of correspondence'with the Committee, you publicly released the text of that document, a,s well as the texts of 153 other documents you authored while.a member of the Atomic Energy Commission regulatory staff.
Would you describe the basis for your decision at that time to release the documents?"
As I noted to in my letters to Senator Hart in June of 1978 on this subject, and in the answer to question 1, the deletions from my note were made in accordance with Exemption 5 of the Freedom of Information Act on the basis that the deleted material reflected advice, recom-mendations, and opinions that were predecisional in nature and the disclosure might tend to inhibit the free exchange of opinion within the staff and the providing of candid : dvice to agency management in the future.
I was concerned, in approving those deletions, only with whether they met a fair reading of Exemption 5.
In reviewing the matter after receiving Senator Hart's letter encouraging release of both the September 25, 1972 note and the other documents that had been withheld by the staff, I concluded that for whatever merit the judicious use of Exemption
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. 5 may have in encouraging the exchange of frank opinions within the staff, my own case was a different one.
As Chairman of the NRC at the time, I recognized in the course of my review of the matter that I had a special 6bligation to make available past documents that I had written whatever their nature.
As I wrote Senator Hart at the time, "Here, I must agree after some reflection, the public interest would have been better served by a prompt release of the full text of my note.
I propose to do that now and also to review the other materials supplied to your staff at the time of my confirmation hearing with the aim of an early release of those not already public."
A day later I wrote Senator Hart saying in part, "I spent last evening reading the 154 documents.
It was a nostalgic experience.
With the exception of one sentence, I am placing the full text of the 154 documents in our. public Document Room.
The single exception is an unnecessarily personal remark in a matter not connected with the work of the technical review staff."
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With the 153 other documents, as with the full text of my September 25, 1972 note, I concluded that the ordinary and reasonable considerations of allowing staff members free reign to trade opinions and predecisional 3
i comments without the inhibitica that having these materials become public records might impose, had to be reconsidered when the author of the documents was Chairman of the agency.
In hindsight, I believe it would have been better for me to have made public the 154 documents along with all of the other materials which were made public at the time of my confirmation hearings.
It would probably have saved us all a good deal of trouble and considerable correspondence.
3.
"With the knowledge and sensitivity gained from this experience, would you please give the Subcommittee your current views on how much information should be made available to the public regarding NRC's activities, and especially its public health and' safety activities? Do you know whether the othe'r Commission. members share your views on this question, and can we be assured that information such as that contained in your 1972 note and in Dr. Hanauer's memorandum will be made available to the public on a timely basis?"
My view is that the NRC needs to conduct its activities in a way that is clearly apparent to the public and the Congress, especially with regard to public health and safety activities.'
I think that is currently the case.
- take some pride in the increase in openness of the NRC process over the years that I was Chairman.
In that time, with appropriate o
recommendations from your Subcommittee and the oversight subcommittees on the House side, the Commission began to make public transcripts of all of its open meetings and to limit the use of Exemption 5 of the Freedom of Information Act.
In fact, at one point I asked the staff to
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. make a study of putting every document the agency produces in the Public Document Room.
It turned out that that was impractical because of the volume of.documentn The facilities and capability of the public Document Room to digest, correlate, and file all of the agency paper simply was not up to the volume being produced.
However, I believe that substantially all of the essential internal documents pertaining to health and safety matters are routinely made public.
There are still some Exemption 5 withholdings of certain internal communications.
For the most part, these are predecisional legal advice from staff counsel, the premature release of which would prejudice the agency's ability to maintain its position in the various litigations that we become involved in, or are predecisional recommendations of the staff for which premature disclosure would prejudice the agency's ability to accomplish its objectives.
Examples of this sort of material would be memoranda of the General Counsel's office advising the Commission on various litigation options in specific cases or staff advice on, or Commission discunion of, positions to be taken with regard to legislation or Congressional testimony.
I think these are proper and legitimate items to be withheld until specific litigation postures are taken in cases or Commission positions on legislation or testimony are given at hearings.
But, as I said before, I believe that most of the agency's essential health and safety business is reflected in the Public Document Room on a timely and continuing basis.
I am sure that my colleagues on the Commission share my belief that the agency's activities, especially in the public health and safety area, must be conducted in a matter that is open and apparent to public and Congressional scrutiny.
I believe that the sort of material contained in the 1972 notes would now be routinely filed in the Public Document Room.
I would note that one of my first actions upon becoming Chairman was to establish a Public Document Room file of:my official correspondence.
4.
"Dr. Hendrie, your June 21, 1978 letter to the Chairman of the Subcommittee included a statement of your present view of the matters connected with you 1972 note, including the acceptability i
of the pressure suppression concept and your reasons for making,
that judgment.
Would you briefly summarize those views?"
My present view is that the pressure suppression containment concept is an acceptable one from the safety standpoint.
It is certainly true that the pressure suppression containments are more complex systems than the dry containments.
From the staff's standpoint, they constitute a more difficult review task, involving analysis of numerous test results to establish appropriately conservative design criteria for the various elements and equipment.,,.,However, the fact that they are more complex l
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. from a review standpoint did not seem to me in 1972, nor does it now, an adequate basis for ruling out an otherwise acceptable design option.
The press,ure suppression containments have both advantages and disadvantages compared to the diy containments.
The large heat sinks (suppression pools or ice volumes) included in the pressure suppression containments mean that there is a place for the absorption of primary system fluid energy released in any breach of the primary system.
This pulls the containment overpressure rapidly down to atmospheric or close to atmos-pheric pressure in a much shorter time than is the case with the dry containments.
This is clearly a safety advantage, since it reduces the time at overpressure during which the containment can leak to the environ-ment.
On the other hand, the pressure suppression containments tend to be smaller in internal volume than the' dry containments, and the control of any hydrogen evolved in a serious accident is thus.more difficult.
Also, there are simply more things that have to work in the event of a significant accident for the pressure suppression concept to be successful.
The staff has adopted quite conservative design and performance criteria for these pressure suppression containment systems, and I believe they are adequate for the purpose.
5.
"What is your own assessment of the safety concerns regarding pressure suppression containments that are discussed in Dr. Hanauer's 1972 memorandum?"
The various technical issues noted in Dr. Hanauer's memorandum, as well as other matters related to pressure suppression containment designs, have been subjects of continuing staff attention and analysis.
I think the various measures that have been required to be implemented in plants, and the conservatisms that are applied by the staff in analyses of pressure suppression containments provide adequate assurance that these containments will function as required in the ' event of an accident.
Ongoing research and analysis work, including the cpntainment-related studies of the Three Mile Island accident, may. indicate better solutions to some of the technical issues raised by Dr. Hanauer and to issues that were identified later.
Such improvements are to be expected in the course of the development and implementation of any major technology.
If such improved measures are developed for pressure suppression containments, they will be applied to operating units as appropriate and necessary and used for new units.
But the prospect for future. improvements does not i
imply that the present pressure suppression containment systems are deficient or unsafe.
To the contrary, as I have indicated before, I believe they are adequate for the units that use the concept.
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6.
"Should the possible consequences for nuclear power development be a factor in the NRC's decision whether to require additional needed safety measures, and was this a factor in your decision on Mr. Hanauer's re' commendation to discourage the further use of pressure suppression containments?"
My view is that if an additional safety measure is determined to be necessary then it must be applied, regardless of the consequences for nuclear power development.
That was also my feeling in 1972.
My note of that time on Dr. Hanauer's memorandum is certainly not clear at all on the point.
As I have said, my feeling, which was not expressed in the note, was that the pressure suppression concept is a reasonable and acceptable form of containment.
Imposition of a requirement that it not be permitted in spite of being acceptable would have certainly had a major effect on nuclear power development, as I said in my note.
7.
"Would you describe in detail your own personal view on the degree of safety that should be the standard adhered to by the NRC in j
making its licensing and regulatory determinations for nuclear power plants? Do you know if that view is shared by your fellow commissioners?"
The statutory safety requirements for nuclear unit licensing are adequate protection of the public health and safety, or no unreasonable risk to the public health and safety, or various other versions of this basic language.
My view has always been that that standard means that the incremental risk to members of the public from nuclear generating units should be a very small additional increment to the normal and everyday risks of life.
Further, it means to me that nuclear electricity is to be supplied by a technology that ~ offers no more overall risk to the public than do alternative means of providing electricity.
The safety 1
philosophy used in achieving that level 'of protection is the. defense-in-depth concept.
Briefly, this requires that nuclear plants be bdilt to a very high quality standard in the first place, that essential safety systems be redundant and be able to function effectively in the event of an accident or other need for their functioning in spite of both an additional failure in the safety systems and loss of offsite power, and-finally that in spite of the protections offered by high quality in initial construction and redundancy of all essential safety systems, that a number of very severe accidents and malfunctions are hypothesized l
and further safety measures are required to deal with these and protect the public.
This basic safety philosophy thus anticipates that there will be errors of design and construction and failures of the equipment including essential safety equipment and that accidents are indeed possible and must be protected against.
Over the years.a substantial body of Commission regulations and staff regulatory guides, technical positions, and staff gui' dance documents have been developed to specify
the detailed measures required to implement this safety philosophy.
Plant design, construction, and operation is judged against this body of l
regulations and staff, documents.
There has been driticism of this body of regulations and staff documents from the standpoint that it does not clearly define a quantitative safety goal or provide a clear statement of how much safety is enough.
It is my view that it would be helpful to have a more precise definition of the meaning of adequate protection and how it is to be achieved.
I believe that my fellow Commissioners share the view that an improved statement of the Commission's guiding safety philosophy and safety goals would be helpful.
You would have to ask my colleagues themselves for a j
more detailed accounting of their views.
8.
"Do the NRC staff members have clear guidance on the standard of safety that they should be requiring in making their safety assessments, or is more guidance needed? What assurances are there that the policies you have described will be carried out in NRC's licensing i
actions?"
I think the existing body of Commission regulations and staff regulatory guides, technical positions, and other documents constitute in sum an adequate guidance to the staff on the standards of safety for licensing purposes and for review of the performance of operating units.
- However, as I noted above, a more precise enunciation by the Commission of the safety goal of " adequate protection" and how it is to be achieved would be helpful.
I think the staff tries very conscientiously to carry out the guidance provided by the Commission in its regulations, policy statements, and discussions at Commission meetings.
Since NRC licensing actions are taken after extensive public hearings before Licens.ing Boards appointed by the Commission, and with review of the decisions of those Licensing Boards by the Appeal Board appointed by the Commission, I think that Commission policies as laid down in the regulations and formal Commission statements are indeed carried out by the staff and that there is a review and check that the staff does carry out the policies laid down.
9.
"The July 1978 Technical Update on Pressure Suppression Type Containments prepared by the Office of Nuclear Reactor Regulation seems to indicate that several early assumptions about the likely performance of these containments were shown to be incorrect, and that other unanticipated difficulties arose as a result of further studies or operating experience.
Why weren't these difficulties
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identified during the AEC's and later the NRC's design review process?
In particular, what was the basis for the early deter-minations that the prassure suppression designs were adequate from a health and' safety standpoint, and in hindsight, was that basis sufficient 'to' support that decision?"
9 The first generation of pressure suppression containment designs were licensed on the basis of test results and analyses from experiments done in connection with the Humboldt Bay and Bodega Bay plant designs.
The results of those test and analyses showed that for a major breach in the primary reactor system, the pressure suppression features of the contain-ment worked adequately to condense the steam and reduce the pressure in the containment.
More sophisicated experimentation techniques, used a decade later in tests conducted specifically to investigate short-term hydrodynamic effects, showed that some of the hydrodynamic loadings that accompany the blowdown of the primary system in the event of the largest loss-of-coolant accidents could reach transient values higher than those
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observed in the Humboldt tests.
A consequence of these later findings i
has been a requirement for increased structural strength in various com-ponents of the early BWR pressure suppression containments.
It should be noted that the basic result of the early test; namely, that the pressure suppression concept worked to condense steam and to keep down the pressure in the containment is not at issue in the later testing.
Nor do the current results show that the early BWR containments in unmodified form would have failed to function effectively in the event of a significant accident.
The current concern and requirements for structural improvements are connected with a desire to restore to those structures the safety margins that had originally been included in them.
Because the newly identified hydrodynamic loads are of very short duration, it is my belief that because of the flexibility and ductility of these large steel structures, they would have accomodated the loads without failure or significant effect on function if a'n accident had occurred.
10.
"It also appears from the 1978 Update thai there are still so-called unresolved safety issues rega> ding the use of pressure suppression containments.
How does NRC go about making a deter-mination that a plant may be licensed or may continue to operate even though such unresolved safety issues exist, and what was the basis for concluding that the plants, such as the Vermont Yankee plant, with pressure suppression containments could continue to operate on an interim basis until these issues are resolved?"
The safety-related design aspects of pressure suppression containments proposed by applicants have been carefully reviewed by the staff and extensive tests and analyses have been done.
The need for conservatism in various system performance aspects and concern about possible problems Y
, such as the technical issues raised by Dr. Hanauer in his 1972 memorandum have been subjects of staff attention for a long time.
As operating experience has accumulated, and as further test and safety research work has been done, se'veral problems in the detailed designs of these systems have been identified.
In each case the staff has reviewed the pertinent design features of the affected operating plants and has required changes in operating procedures and equipment modifications to maintain adequate safety margins.
An example is the identification of new suppression pool hydrodynamic loads referred to above that had not been explicitly included in the original design basis of the BWR pressure suppression containments.
There is an extensive staff report, NUREG-0408, on this i
subject.
All of these matters,. including those listed by Dr. Hanauer have been taken into account in the licensing of the individual plants.
j There have been many tests and experiments on pressure suppression containment designs and phenomena.
These have included the test work done by the reactor vendors in support of their designs, tests performed for utilities with plants using the pressure suppression concept, NRC-sponsored tests at Lawrence Livermore Laboratory, and tests in Sweden, Germany, Japan, and Italy.
The NRC has access to the tests results from i
other countries through joint participation and through agreements for exchange of safety-related information with foreign regulatory agencies.
The body of test data available on pressure ' suppression containments goes far beyond that supplied by the reactor vendors.
A summary of the test work through 1978 and that still in progress at that time is given in NUREG-0474, the technical update report on pressure suppression containments by the staff.
All of this work goes into the staff's determination that a plant may be licensed or may continue to operate in spite of the various technical issues that may exist.
This is the case specifically for Vermont Yankee, as for other operati.ng units.
I should comment that tha termi; " generic issues." o!" unresolved' safety l
questions" are useLi to designate matters that apply to a number of i
plants and for which individual plant requirements and modifications have been judged adequate for individual license issuance or continued i
operation.
These matters are appropriately considered on a generic basis, since they do apply to a number of units and it is more efficient to do the research and analysis work on a generic basis.
I believe that licensing can continue and that operating units can continue to operate where appropriate individual consideration has been given to each of these issues in the context of a specific plant and specific modifications or operating procedure changes instituted to provide adequate safety.
In my view, it is not necessary to solve all problems with the ultimate and final solutions before any licensing may go on or operation continue, provided there are reasonable and adequate interim measures that may be implemented on the indiiidual plants concerned.
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Answers to Questions asked of Dr. Hanauer by Senator Stafford at the hearing of the Subcommittee on Nuclear Regulation of the Senate Committee on Environmental and Public Work, February 28, 1980.
1.
Question Dr. Hanauer, your September 20, 1972 memorandum appears to identify some seven safety concerns you had at that time regarding the use of pressure suppression containments.
The NRC's 1978 update document lists actions taken by the agency on each of these concerns.
How satisfied are you with the progress that has been made on each of these items, are they still valid concerns, and how serious are they in terms of affecting the safety of the plants using this type of design?
Answer These items are valid concerns, in my opinion, in that they are things to watch for now and in the future.
I am generally satisfied with the progress that has been made.
The ongoing program to establish design basis loads that are appropriate for the anticipated life of facilities with pressure-suppression containments, and to restore the originally intended design safety margins for plants with General Electric Mark I design plants, is going more slowly than previous planned, being about a year behind the' schedule given in the NRC Annual Report for 1978 (page A-7),
l The safety seriousness of the seven concerns enumerated in ray 1972 memorandum vary; all but the last, if they turned out really badly, could jeopardize the containment function in the unlikely event of a large loss-of-coolant O
accident.
I believe that, in the state of knowledge today, adequate assurance is available that the public health and safety is not jeopardized.
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Question What was the basis for your recommendation to discourage the further use of pressure suppression containments in 1972 -- was it a concern about the safety impacts of the items you identified in your memorandum at that time, or was it a concern about the difficulty in assessing the ade-quacy of pressure suppression designs?
Answer Both.
The large amount of resources that I foresaw would have to be expended by industry (the ratepaying public) and the agency (the taxpaying public) in resolving these safety issues to assure public protection were my concerns.
I had no doubt then, and have none now, that piant modifications and improved analyses can be obtained that do in fact resolve the issues.
I was correct about the large resources.
For the Mark I design basis load problem I referred to in n1y answer to Question 1 above, the industry resources already expended, roughly estimated, are over $50 million in costs for tests and generic analysis, plus an additional $15-20 million per plant to be spent in hardware modifications and plant-specific analyses.
The government has spent about $21/2 million in review and confirmatory research.
3.
Question In your judgement, are the concerns you identified regarding these con-tainment designs sufficiently resolved to assure the safety of the plants now operating with these designs?
Answer o
Yes.
The margins of safety will be restored to their originally intended values, and public protection thereby enhanced, when t,he plant hardware modi-fications, discussed 1ri nty answers to Questions 1 and 2 above, are completed in a year or two.
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