ML19291D491
| ML19291D491 | |
| Person / Time | |
|---|---|
| Issue date: | 08/18/1981 |
| From: | Dircks W NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | |
| References | |
| TASK-RICM, TASK-SE SECY-81-245A, NUDOCS 8109170437 | |
| Download: ML19291D491 (37) | |
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RULEMAKING ISSUE (Commission Meeting)
For:
The Commissioners 7
/
j From:
William J. Dircks, Executive Director for Operatiorfsx
Subject:
INTERIM AMENDMENTS TO 10 CFR PART 50 RELATED TO HY R Eh00}iTd0
Purpose:
To obtain Commission approval for publication of proposed and final amendments in the Federal Register.
Category:
This paper covers a major policy question.
Issue:
(a) Whether applicants and licensees of light-water nuclear power plants should be required to provide inerted contain-ment atmospheres for Mark I and II BWRs; (b) Whether applicants and licensees of BWRs and PWRs that rely on purge /repressurization systems as the primary means for controlling combustible gases following a LOCA should be required to have certain types of hydrogen recombiner cap-ability for use following the start of an accident.
(c) Whether applicants and licensees of Mark III BWRs and FWR Ice Condenser facilities should be required to provide 3
hydrogen control systems that can handle large amounts of hydrogen; (d) Whether applicants and licensees of BWRs and PWRs should be
-(
required to demonstrate the survivability of certain safety systems during and following a hydrogen burn; and (e) Whether applicants and licensees of BWRs and PWRs should be i
required to perform and submit analyset concerning hydrogen control, containment structural integrity and safety system survivability.
Ciscussion:
During the Policy Session on April 23, 1981, the Commission was briefed by the staff on Effective Interim Amendments to 10 CFR a
Part 50 Related to Hydrogen Control and Certain Degraded Core Considerations (SECV-81-245).
As noted in Enclosure "A". the Cxciscion indicated that further consideration would be given
Contact:
M. R. Fleichman 443-5981 8109170437 810818 CF SUBJ CF
The Commissioners 2
to the amendments at a later Commission meeting.
During the Policy Session on April 30, 1981, the Commission reviewed SECY-81-246 and approved for publication in the Federal Register a notice of proposed rulemaking that would incorporate into 10 CFR Part 50 a set of TMI-2 requirements for operating license applications (Enclosure "B").
This proposed rule was published in the Federal Register on May 13, 1981 and a similar rule with
. respect to operating reactors was disapproved by the Commission (SECY-81-422 dated July 15, 1931) on August 6,1981.
~The InteFiiiRule (SECY-81-245), which was discussed with the Commission on April 23, 1981, covered the following specific items:
1.
Inerting of Mark I and II BWRs 2.
H2 Control for Mark IIIs and Ice Condensers 3.
Equipment Survivability 4.
Analyses 5.
Dedicated H2 Control Penetrations 6.
H2 Recombiner Capability 7.
High Point Vents 8.
Post-Accident Protection of Safety Equipment and Areas 9.
In-Plant Iodine Instrumentation 10.
Post-Accident Sampling 11.
Leakage Integrity Outside Containment 12.
Accident Monitoring Instruments 13.
Detection of Inadequate Core Cooling 14.
Training and Human Engineering Of the above list, items 5, and 7 to 14 were included in the pro-posed rule for operating license applications that was published on May 13, 1981.
The remaining five items (i.e., 1 to 4, and 6) deal primarily with hydrogen control and are hereby being resub-mitted for Commission consideration.
Items 2 and 3, on hydrogen control for Mark III BWRs and ice condensers PWRs, and equipment survivability, were not previously published for comment.
The implementation dates for these items have also been revised for consistency with the proposed rule on operating license applications.
In view of the fact that the requirements for inerting of Mark I and II BWRs and hydrogen recombiner capability were previously proposed for comment (45 FR 65466), the staff recommends that these items be published as a final rcle (Enclow re "C").
The remaining hydrogen control requirements, namely nydrogen control for Mark III BWRs and ice condenser PWRs, assurance of contain-ment structural integrity and equipment survivability during and following a hydrogen burn, and supporting analyses, should be pub-lished as a proposed rule for public comment since they were not previously proposed (Enclosure "D").
In order to specify more completely the analysis needed to support the hydrogen control
The Commissioners 3
for Mark III and ice condenser containments and system sele 3
the assuran e containment structural integrity and equipment survivability, the staff is proposing to provide supplementary guidance to be used by the respective designers (see Enclosure "0").
Recommendations:
That the Commission:
1.
Approve the publication of final amendments, as set forth in Enclosure "C", which would require the inerting of Mark I and II BWR containments and hydrogen recombiner capability for certain LWRs.
2.
ADprove the publication of proposed amendments, as set forth in Enclosure "D", which would require hydrogen cmtrol systems for Mark III BWRs and ice condenser PWRs, assurance of con-tainment structural integrity and equipment survivability during and following a hydrogen burn, and supporting analyses for certain LWRs.
3.
Note:
(a) That these amendments are applicable to LWRs whose cps were issued prior to March 28, 1979.
Other amendments pertaining to applicants with pending CP and manufactur-ing license applications were published for comment on March 23, 1981 and are also described in NUREG-0718, Rev. 1 dated July 14, 1981.
Requirements for future generations of LWRs are under development.
(b) That the notice of final rulemaking in Enclosure "C" will be published in the Federal Register to be effec-tive 30 days after publication.
(c) That the notice of proposed rulemaking in Enclosure "D" will be published in the Federal Register allowing 60 days for public comment.
(d) That pursuant to S 51.5(d) of Part 51 of the Commission's regulations neither an environmental impact statement nor a negative declaration need be prepared in connec-tion with the amendment since the amendment is nonsub-stantive and insignificant from the standpoint of environmental impact.
(e) The reporting requirements in connection with the analyses required by the proposed rule (Enclosure "D")
are being submitted for OMB review and approval under the Paperwork Reduction Act.
(f) Th:t pursuant to the Regulatory Flexibility Act of 1980, the proposed rule contains a statement that the Commission
The Commissioners 4
certifies that the rule will not, if promulgated, have a significant economic impact upon a substantial number of small entities and a copy of this certification will be forwarded to the Chief Counsel for Advocacy, SBA by the Division of Rules and Records, ADM.
(g) That the Subcommittee on Nuclear Regulation of the Senate Committee on Environment and Public Works, the Subcommit-tee on Energy and the Environment of the House Committee on Interior and Insular Affairs, the Subcommittee on Energy Conservation and Power of the House Committee on Energy and Commerce, and the Subcommittee on Environment, Energy and Naturai Resources of the House Committee on Governr.ent Operations will be informed.
(h) That a public announcement will be issued (Enclosure "E").
(i) That copies of the Notices of Final and Proposed Rule-making will be distributed by TIDC, ADM to each affected licensee and other interested parties.
Sunshine Act:
Recommend affirmation at an open meeting.
William'JI Dircks Executive Director of Operations
Enclosures:
"A" - Memorandum Chilk to Dircks dated 4/27/81 "B" - Memorandum Chilk to Dircks dated 5/8/81 "C" - Notice of Final Rulemaking "D" - Notice of Proposed Rulemakina "E" - Draft Public Announcement DISTRIBUTION Commissioners Commission Staff Offices Exec Dir for Operati s
Exec Legal Director ACRS ASLBP ASLAP Secretariat 6
[7590-01]
NUCLEAR REGULATORY COMMISSION 10 CFR Part 50 Interim Requirements Related to Inerted Reactor Containments and Hydrogen Recombiner Capability AGENCY:
Nuclear Regulatory Commission.
ACTION:
Final Rule.
SUMMARY
The Nuclear Regulatory Commission is amending its regulations to require inerted containment atmospheres and additionally, hydrogen recombiner capability to reduce the likelihood of venting radioactive gases follow.ng an accident.
The inerting requirement applies only to boiling water nuclear power reactors with either Mark I or Mark II type containments; the requirement for hydrogen recombiner capability applies to light-water nuclear power reactors that rely upon purge /repressuriza-tion systems as the primary means of hydrogen control.
EFFECTIVE DATE:
[30 days following publication in the Federal Register)
FOR FURTHER INFORMATION CONTACT:
Morton R. Fleishman, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commiss_ ion, Washington, D.C.
20555, telephone 301-443-5981.
SUPPLEMENTARY INFORMATION:
On October 2, 1980, the Nuclear Regulatory Commission published in the FEDERAL REGISTER (45 FR 65466) a notice of proposed rulemaking on " Interim Requirements Related to Hydrogen Control and Certain Degraded Core Considerations" (Interim Rule) inviting written comments or suggestions on the proposed rule by November 3, 1980.
The 1
Enclosure "C"
[7590-0.1]
notice concerned Um:= d rend: rents to 10 CFR Part 50, " Domestic Licensing of Production and Utilizat on Facilities," to improve hydrogen manage-i ment in light water reactor facilities and to provide specific ~ design and other requirements to mitigate the consequences of accidents resulting in a degraded reactor core.
Thirty-five persons submitted comments regarding the proposed
~
amendments.
Although the comment period was scheduled to expire on November 3, 1980, comments received subsequent to that date have been considered, with the latest comment letter being dated February 9, 1981.
The comments are part of the public record and may be examined and copied in the Commission's Public Document Room at 1717 H Street NW., Washington, D.C.
A summary of the comments along with a comment analysis and a value/ impact assessment are also available for inspection and copying in the Public Document Room.
These comments have been carefully reviewed and evaluated during preparation of this final rule.
The final rule contains revisions to the proposed rule that reflect these comments.
The commenters were about equally divided between those in favor of and those opposed to publishing the interim amendments.
Whether or not the commenter favored publishing a final rule, additional detailed comments were generally provided on specific aspects of tha proposed amendments.
The NRC's Office of Nuclear Reactor Regulation sent a letter on September 5, 1980 to all nuclear power plant licensees, applicants and construction permit holders providing a " Preliminary Clarification of the TMI Action Plan Requirements." This was followed by a series of four regional meetings, noticed by publication in the FEDERAL REGISTER (45 FR 60508) and held during the week of September 22, 1980, in order 2
Enclosure "C"
~
[7590-01]
to provide a more detailed explanation of the requirements and to cbtain industry comments.
Based on the discussions at the meetings and other comments received, the NRC revised the requirements and notified the applicants, licensees and construction permit holders to this effect by a letter dated October 31, 1980.
The letter and revised requirements are included in NUREG-0737, " Clarification of TMI Action Plan Requirements."1 On May 13, 1981, the Commission published in the FEDERAL REGISTER (46 FR 26491) a notice of proposed rulemaking which proposed licensing requirements for pending operating license applications (Oi Rule).
The proposed OL Rule was based upon the requirements described in NUREG-0737 and includes, among others, many of the requirements originally included in the proposed Interim Rule published in October 1980.
Items originally proposed in the Interim Rule were:
1.
Inerting of Mark I and II boiling water reactors (BWRs) 2.
Design analyses for Mark III BWRs and pressurized water reactors (PWRs) 3.
Dedicated hydrogen control penetrations 4.
Hydrogen recombiner capability 5.
High point vents 5.
Post-accident protection of safety equipment and areas In plant iodine instrumentation
~*
8.
Post-accident sampling 9
Leakage integrity outside containment ICepies of this report may be obtained from GPO Sales Program, Division of Technical Information and Document Control, U.S. Nuclear Regulatory Commission, Washington, D.C. 20555.
3 Enclosure "C"
[7590-01]
10.
Accident monitoring instrumen = ic.r 11.
Detection of inadequate core cooling 12.
Training to mitigate degraded core accidents Of the above list, all except items 1, 2 and 4 were included in the proposed OL Rule and have been appropriately revised to reflect the comments received during the comment period on the final Interim Rule.
- Hence, those items included in the OL Rule have been deleted from this Interim Rule.
Furthermore, those public comments received pertaining to the OL Rule items will not be discussed here.
They may be examined and copied in the Commission's Public Document Room along with the response to the comments (SECY 81-245, " Interim Amendments to 10 CFR Part 50 Related to Hydrogen Control and Certain Degraded Core Considerations").
The final Interim Rule contains revisions to the proposed Interim Rule that reflect all of the applicable comments including those (a) given in response to the notice of proposed rulemaking, and (b) generated during the regionel meetings and in response to the clarification letters of September 5, 1980 and October 31, 1980.
Before discussing the comments and the specific revisions resulting from the comments, it should be noted that, while 6 50.44 has applied only to light-water nuclear power reactors with zircaloy fuel cladding, the new amendments in the Interim Rule are not as limited and apply to light-water nuclear power reactors with either stainless steel or zircaloy fuel cladding.
The Commission will be considering further modification of 650.44 during the long-term rulemaking effort relative to consideration of degraded or melted cores in safety regulation.
Part of this long-term rulemaking will involve a thorough reevaluation of hydrogen generation and control.
In the interim, the Commission wishes 4
Enclosure "C"
[7590-01]
to leave in place the existing provisions of s50.44 because of its requirements for dealing with design basis accidents.
These include, for example, requiring:
1.
The capability for measuring hydrogen concentrations in containment.
2.
The capability for ensuring a mixed atmosphere in containment.
3.
The capability for controlling combustible gas concentrations in containment following a postulated LOCA.
4.
The capability to deal with hydrogen from radiolytic decom-position of the reactor coolant and the corrosion of metals.
These have release characteristics that differ from those associated with metal-water reaction.
5.
That the combustible gas control systems conform with the general requirements of Criteria 41, 42 and 43 of Appendix A of 10 CFR Part 50.
Severa1 commenters have expressed concern that the various rule-makings currently being pursued by NRC should be integrated, i.e., safety goal, degraded core considerations, minimum engineered safety features, siting and emergency planning.
The NRC shares this concern.
On October 15, 1980 t1e Executive Director for Cparations established a Degraded Cooling Steering Group to coordinate degraded cooling and related rules.
This group has completed its work anc prepared a plan to ensure future integration of these activities.
Numerous commenters have questioned many of the implementation dates specified in the rule, indicating that they cannot be met for a variety of reasons, such as procurement lead time, need for-the design studies, 5
Enclosure "C"
[7590-01]
availability of acceptable equipment, etc.
The staff agrees -ita +.haza comments and has made appropriate changes to the implementation dates.
INERTING OF MARK I & II BWRs [9 50.44(c)(3)(i)]
Some commenters, particularly those associated with Mark I boiling water reactors (BWRs), questioned the a/"isability of requiring inerting of containments and suggested that other hydro, control options be permitted.
This issue has been extensively reviewed and discussed among the Commission, NRC statf and industry participants.
Numerous reports and letters have been written and many meetings held in order to thoroughly air the issue.
Considering the information previously developed, the Commission continues to believe that it would be prudent, pending com-pletion of the long term rulemaking on degraded core cooling, to require that all Mark I and II BWR containments be provided with an inerted atmosphere during normal operations.
The proposed rule's deadline for installation of inerting systems has been extended to account for delay in publication of a final rule.
The rule has also been changed to clarify that the paragraph applies only to Mark I and II DWRs.
HYDROGEN RECOMBINER CAPABILITY [S 50.44(c)(3)(ii)]
Several commenters have recommended that S 50.44(c)(3)(ii) be modi-fied to allow the use of alternate means of hydrogen control, such as internal recombiners, rather than restrict the rule to external recom-biners.
The proposed rule was not intended to preclude this alternative.
6 Enclosure "C'
[7590-01]
In fact, if internal recombiners were present before or will be installed in the future, this section of the rule would not apply since purge /
repressurization systems would not be the primary means for combustible gas control.~ This section of the rule only applies to facilities that rely upon purge /repressurization systems as the primary means of con-trolling combustible gases following a LOCA.
It should also be noted that this section of the rule does not require actual installation of external recombiners, rather, it requires only the capability for installation.
To avoid confusion, the rule has been clarified to indi-cate that internal recombiners are an acceptable alternative to the installation of external recombiner capability.
REGULATORY FLEXIBILITY ACT In accordance with the Regulatory Flexibility Act of 1980, 5 U.S.C.
605(b), the Commission hereby certifies that this rule will not, if pro-mulgated, have a significant economic impact on a substantial number of small entities.
This rule affects only the licensing and operatiori of nuclear power plants.
The companies that own these plants do not fall within the scope of the definition of "small entities" set forth in the Regulatory Flexibility Act or the Small Business Size Standards set out in regulations issued by the Small Business Administration at 13 CFR Part 121.
Since these companies are dominant in their service areas, this rule does not fall within the purview of the Act.
Accordingly, notice is hereby given that, pursuant to the Atomic Energy Act of 1954, as amended, the Energy Reorganization Act of 1974, as amended, and section 553 of title 5 of the United States Code, the 7
Enclosure "C"
[7590-01]
following amendments to 10 CFR Part 50 are published as a Secument sub-ject to codification.
PART SD--DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES 1.
The authority citation for Part 50 reads as follows:
AUTHORITY:
Secs. 103, 104, 161, 182, 183, 189, 68 Stat. 936, 937, 948, 953, 954, 955, 956, as amended (42 U.S.C. 2133, 2134, 2201, 2232, 2233, 2239); secs. 201, 202, 206, 88 Stat. 1243, 1244, 1246 (42 U.S.C., 5841, 5842, 5846), unless otherwise noted.
Section 50.78 also issued under sec. 122, 68 Stat. 939 (42 U.S.C. 2152).
Sections 50.80-50.81 also issued under sec. 184, 68 Stat. 954, as amended; (42 U.S.C. 2234).
Sec-tions 50.100-50.102 issued under sec. 186, 68 Stat. 955; (42 U.S.C. 2236).
For the purposes of sec. 223, 68 Stat. 958, as amended; (42 U.S.C. 2273),
650.54 (i) issued under sec. 161i, 68 Stat. 949; (42 U.S.C. 2201(i)),
SS50.70, 50.71 and 50.78 issued under sec. 1610, 68 Stat. 950, as amended; (42 U.S.C. 2201(o)) and the Laws referred to in Appendices.
2.
Section 50.44 of Part 50 is amended by revising paragraph (c) to read as follows:
650.44 Standards for combustible gas control system i.n light water cooled power reactors.
(c)(1) For each boiling or pressurized light-water nuclear power reactor fueled with oxide pellets within cylindrical zircaloy cladding, it shall be shown that during the time period following a postulated LOCA but prior to effective operation of the combustible gas control system, 8
Enclosure "C"
[7590-01]
either:
(i) An uncontrolled hydrogen-oxygen recombination would not take place in the containment; or (ii) the plant could withstand the conse-quences of uncontrolled hydrogen-oxygen recombination without loss of safety function.
(2) If neither of these conditions can be shown, the containment shall be provided with an inerted atmosphere or an oxyger deficient condi-tion in order to provide protection against hydrogen buining and explo-sions during this time period.
(3) Notwithstanding paragraphs (c)(1) and (c)(2) of this section:
(i) [As seen-as practicabie-bet-not-inter-than-dene-30--1981] Effec-tive [4 months after the effective date of,r.he rule] or 6 mcnths after initial criticality, whichever is later,* an inerted atmosphere shall be provided for each boiling light-water nuclear power reactor with a Nark I or Mark II type containment; [feeility-for which-the-applicatien-fer-a centainment permit was-decketed-between-March-157-1964-and-dely-17-1972-]
and (ii)[(iv3--By-daneary-1--1982;-f acilities] Effective [24 months after the effective date of the rule] all licht-water nuclear _gewer reactors that rely upon purge /repressurization systems as the primary means for controlling combustible gases following a LOCA shall be provider! with either internal recombiners or_ the capability to install external recom-biners following the start of an accident.
The internal or external recombiners must [that] meet the combustible gas control requirem9nts in paracraph (d) of this sectian.
The containment penetrations that are used must [ meet-the-criteria-in paragraphs-(e3(3)(A3-ant-te3(3)(B3 of-this-sectien-spplicabie-to-externai-recembiners-] either be:
- Comparative text.
Additions shown by underline, deletions by bracket and crossout.
9 Enclosure "C"
i
[7590-01)
(A) dedicatg.d to that servicp oniv, conform to the recui_rements of Criteria 54 and 56 of Append 5r. A of this part, be designed against pos,tulated single failures for containment isolation ourooses, and be sized to satisfy the flow reduirener.ts of the external recombiners, or (B) of a combined design for usa by either external recombiners or purge /repressurization systems and other systems, conform to the g
requireq3nts of, Criteria 54 and 56 of Appendix A of this part, be desioned 1
against postuiated single failures both for containment isolation ourposes aryd for qqg' ation of the external recombiners or ourge/repressurization systens, and be sized to satisfy the flow recuirements of the external recembiners or ourge recre;surization systems.
Dated at Washington, D.C. this day of 1981.
For the Nuclear Regulatory Commission.
Samuel J. Chilk, Secretary of the Commission.
I
(
5 10 Enclosure "C"
g 4
ENCLOSURE D
[7590-01]
NUCLEAR REGULATORY COMMISSION 10 CFR Part 50 Interim Requirements Related to Hydrogen Control AGENCY:
Nuclear Regulatory Commission.
ACTION:
Proposed Rule.
SUMMARY
The Nuclear Regulatory Commission is considering amending its regulations to improve hydrogen control cspability during and following an accident in light-water reactor facilities.
The amendments would require improved hydregen cor. trol systems for boiling water reactors with Mark III type containments and for pressur' ired wate* reactors with ice condenstr type containments.
All light-water nuclear power reactors not relying upon an inerted atmospnere for hydrogen control would be required to shcw that certain important safety systems must be able to function during and following hydrogen burning.
DATES:
Comment period expires [60 days following publication in the FEDERAL REGISTER].
FOR FUATHER INFORMATICN CONTACT:
Morton R. Fleishman, Office of Nuc. lear Regulatory Research, U.S. Nuclear Regulatory Commission, Washington, D.C.
20555, telephone 301-443-5981.
ADDRES.5-Written comments or suggestions for consideration in connection with the proposed ameadments should be submitted to the Secretary of the 1
Enclosure "D"
[7590-01)
Commission, U.S. hclear Regulatory Commission, Washington, D.C. 20555, Attention:
Docketing and Service Branch.
Copies of comments received msy be examined in the Commission's Public Document Room at 1717 H Street NW., Washington, D.C.
SUPPLD1ENTARY INFORMATI0tc The accident at Three Mile Island, Unit 2 (TMI-1) resulted in a severely damaged or degraded reactor core. a con-comitant release of radioactive material to the prilt.ary coolant rystem, and a fuel cladding-water reaction which resulted in the generation of a large amcunt of hydrogen.
The Nuclear Regulatory Commission has taken numerous actions to correct the design and operational limitations revealed by the accident.
Included in these actions are several rule-making proceedings intended to improve the hydrogen control capability of light-water nuclear power reactors.
On October 2, 1980, the Nuclear Regulatory Commission published in the FEDERAL REGISTER (45 FR 65466) a notice of proposed rulemaking on " Interim Requirements Related to sydragen Control and Certain Degraded Core. Considerations" (Interim Rule).
Tne notice concerned proposed amendments to 10 CFR Part 50,
" Domestic Licensing of Production and Utilization Facilities," to improve hydrogen management in light-water reactor facilities and to provide specific design and other requirements to mitigate the con-sequences of accidents resulting in a degraded reactor core.
On March 23, 1981, the Commission published in the FEDERAL REGISTER (46 FR 18045) a notice of proposed rulemaking on " Licensing Requirements for Pending Construction Permit and Manufacturing License Applications."
The notice proposed a set of licensing requireets applicaSle to con-struction permit applications that stemmed from lessons learned from the 2
Enclosure "D"
[7590-01]
TMI-2 accident.
On May 13, 1981, the Commission published in the FECE UL REGISTER (46 FR 26491) a notice of proposed rulemaking on " Licensing Recuirements for Pending Operating License Applications" (OL Rule).
As a result of the various activities and considerations relative to the October 2, 1980 notice, the Commission decided to split the Interim Rule into two parts.
One part was to be included in the OL Rule.
The other part, limited only to hydrogen control, was to be issued separately.
The details of this split are described in the companion FEDERAL REGISTER notice appearing elsewhere in this issue (see Table of Contents under NRC Rules and Regulations) related to inerting and hydro-gen recombiner capability.
The Commission has also been considering the ability of all licht-water reactors, particularly pressurized light-water reactor facilities with ice condenser type containments and boiling light-water reactor facilities with Mark III type containments, to withstand an accident with the concomitant generation of large amounts of hydrogen, such as the type which occurred at Three Mile Island, Unit 2 (TMI-2).
As a result, three new amendments to the regulations are being proposed for public comment.
HYDROGEN CONTROL FOR MARK III 3WRs AND ICE CONDENSER PWRs [g 50.44(c)(3)(iii)]
It is proposed that boiling water reactor (BWR) facilities with Mark III type containments and pressurized water reactor (PWR) facilities with ice condenser type containments, for which construction permits were issued prior to March 28, 1979, be required to install hydrogen control systems capable of accommodating an amount of hydrogen equivalent to that generated from the reaction of 75% of the fuel cladding (surrounding the active fuel region) with water, witnout loss of containment integrity.
This 3
Enc 1csure "D"
[7590-01]
new requirement is being contemplated as a result of safety issucs raised during licensing reviews of new ice condenser and Mark III plants.
In these reviews, it has become clear that additional protection is required to provide assurance that large amounts oi' hydrogen can be safely accom-modated by these plants.
The particular type of hydrogen contrcl system to be selected is left to the discretion of the applicant or licensee; however, it must be found acceptable by the NRC based upon suitable programs of experiment and analysis.
The selection should be supported by comparative analyses of alternative systems to show their relative advantages and disadvantages.
These comparisons are to be submitted as part of the analyses required under S 50.44(c)(3)(v).
At present, a distributed igniter system has been found acceptable for the Sequoyah plant with an ice condenser containment, but only as an interim solution while tha hydrogen control matter is studied further.
A post-accident inerting system has also been discussed for the ice condenser and Mark III containments.
Whatever systems are finally proposed and approved for the long term, large amounts of hydrogen must be safely accommodated, and operation of the system, either intentionally or inadvertently, must not further aggravate the course of an accident or endanger the plant during normal operations.
The amount of hydrogen to be assumed in the design of the hydrogen control system is that amount generated by assuming that 75% of the fuel cladding surrounding the active fuel region reacts with water.
The 75% is judged to be representative of the maximum amount of hydrogen likely to be generated in en accident in which the threat to the containment is limited to the threat posed by the combustion of hydrogen.
Events with metal-water reactions in excess of 75% are judged to have a very low probability of termination before core melt.
This 4
Enclosure "0"
[7590-01]
75% value also appears to be reasonable because it is sufficiently greater than the fuel cladding-water reactirn analyzed to have occurred at TMI-2 to provide a conservative estimate for the cladding reaction that may occur during a TMI type degraded core accident.
It is expected that the 75% value will permit plants that are either completed or are well along in the construction stage to have a hydrogen control system added without the need for major modifications to their containment structures.
Research now in place will, over the next several years, yield data on the likeli-hood of termination of sequences with large amounts of cladding interaction.
Owners of Mark III BWRs now under construction have been surveyed Dy the NRC staff to determine the effect on their plant designs of the requirement that they do not exceed ASME Service Level A Limits or the Service Load Category during inadvertent full inerting of a post-accident inerting system.
This survey was conducted because a post-accident inerting system (rather than a distributed ignition system) was thought to be the nreferred approach for the Mark Ill containments.
Based on their responses, the Commission has concluded that there would be no significant impact in specifying these requirements for inadvertent full inerting.
Modest deviations from these ASME criteria will be permitted if good cause is shown.
A comparable survey was not conducted for ice condenser plants because the distributed ignition system apparently is the approach preferred by the owners of these plants.
There are ongoing programs of research in a number of areas of hydro-gen generation, release, burning, and control.
These include the analysis of accident sequei.tas, the chronology of hydrogen and steam injection (from the primary system into containment), the analysis of operations 5
Enclosure "D"
[7590-01']
to recover coolability, and an assessment of equipment survivability.
These studies are expected to reveal the advantages and disadvantages of various hydrogen control systems, including those that involve deliberate burning of the hydrogen within containment.
Based on the state of tech-nology as of August 1981, the Commission believes that control methods that do not involve burning provide protection for a wider spectrum of accidents than do those that involve burning.
As a result of the review of the deliberate ignition systems installed at Sequoyah and McGuire, the staff has identified issues which need to De investigated further.
A spectrum of degraded core accident scenarios, including those which may lead to inadvertent suppression of combustion in the lower compartment due to a steam rich atmosphere, and several hydrogen combustion phenoment are continuing to be reviewed.
In addition, there is incomplete verification of analytical models.snd equip-ment survivability.
These issues are being addressed in ongoing research by NRC ar.d the nuclear industry.
The Commission concludes that the issues are sufficiently resolved to warrant interim approval of deliberate igni-tion systems for ice condenser plants.
However, the Commission has required in individual licensing proceedings and,in the section of this rule on analyses (S50.44(c)(3)(v)) that studies of alternative hydrogen management systems be performed prior to the long-term approval of any particuiar method.
6 Enclosure "D"
[7590-01]
SURVIVABILITY OF CERTAIN SAFETY SYSTEMS DURING AND FOLLOWING A HYDROGEN BURN [y 50.44(c)(3)(iv)]
A new requirement is being considered on safety system survivability.
(In this context, survivability differs from qualification, as used else-where, in that generous application of safety 9,argins is not required.)
It would apply to all BWRs and PWRs, for which construction permits were issued prior to March 28, 1979, that do not have an inerted containment atmosphero for hydrogen control.
That is, plants for which there exists the possibility that substantial amounts of hydrogen can be burned in the containment will be covered by the proposed new requirement.
Safety systems provic~ed on tnece plants that are needed (a) to shut down the reactor and maintain the reactor in a safe shutdown condition, and (b) to prevent loss of containment integrity, must survive the environmental conditions associated with hydrogen burning and local detonations.
- Thus, for example, if a distributed igniter system is selected for controlling large amounts of hydrogen, the applicants or licensees must assure that the specified safety systems can survive and continue to perform their needed safety functions during and following hydrogen burning.
If no new hydrogen control system is required, as is likely to be the case for PWRs with large dry containments, these applicants and licensees would still hue to perform analyses to:
(1) show containment structural integrity, as defined in 5 50.44(c)(3)(iii) can be maintained; and (2) assure that the specified safety systems can continue to perform their needed safety functions during and following hydrogen burning and local detonations.
This survivability requirement for certain identified essential systems is needed because the environmental pressures and temperatures assoc.iated with hydrogen burning and local detonations can 7
Enclosure "D"
[7590-01]
be more severe than the conditions for which the equipment has been pre-viously qualified.
ANALYSES [6 50.44(c)(3)(v)]
The proposed Interim Rule required that for all PWR and BWR plants, except the Mark I and II BWRs, design analyses must be performed for new hydrogen control measures.
Many commenters indicated that the descrip-tion of the design analyses was not precise enough to elicit the desired response.
Furthermore, several commenters have suggested that it is inappropriate to have a regulation requiring hydrogen control design studies in view of the fact that unambigious event descriptions and accept-ance criteria are not supplied.
The Commission agrees with these comments in part.
As a result, the Commission intends to provide supplementary guidance concerning acceptable procedures that should be used, both for design of the hydrogen control systems per S 50.44(c)(3)(iii), for the demonstration of equipment survivability per S 50.44(c)(3)(iv), and for the analysis of containment structural integrity.
The Commission is considering three different approaches concerning, the supplementary guidance to be provided for performing the analyses.
In tne first approach, the Commission would identify accident secuences or scenaria which are found by probabilistic risk assessment techniques to M significant contributcrs to the likelihood of core degradation and thus pose a significant hydrogen threat.
The licensee would then perform analyses, using tNse segrances, to determine the tie variation of the hydrogen and suam release rates to the containment building.
The anal-yser., which would include the failure assumptions of the different 8
Enclosure "D"
[7590-01]
scenarios as well as the accident recovery phase and allowances for uncertainties, would provide the pressure and temperature histories to which the containment would be exposed.
A list of possible accident sequences being considered under this approach is given in Table I.
The scenarios include the production of subst6atial amounts of hydrogen as part of core-melt seque; ices; they were selected, based on experience and engineering judgment, because they are the more pro.%ble severe accident sequences which could be terminated short of primary vessel melt-through with available recovery techniques.
In the second approach, a base sequence would be chosen by the Commission based on its significance and t tracteristics from the stand-point of hydrogen threat.
Key aspects of this scenario would then be parametrically varied, by the licensee, in determining the acceptability of the hydrogen control system or the containment response.
This would provide a wider range than that of the selected base sequence alene.
The acceptability of the analyses used in this approach would depend on the selection and range of the parameters being varied.
The range must be chosen to include the effects of physically realistic degraded core accident scenarios with recovery.
Table II represents a preliminary list of parameter variations that appear to provide reasonable extensions of a PWR small-break scenario (Item 1 of Table I).
A corresponding BWR list has not yet been prepared.
In the third approach, the Commission would use a set of accident sequences as in Tabh I, and perform analyses which would define a reason-able envelope of time histories of hydrogen and steam release rates into the containment building.
This envelope definition could be based on variations in the progression of different sequences and/or variations 9
Enclosun. "0"
[7590-01]
Table I.
Accident Sequences Leading to a Significant Hydrogen Threat PWR 1.
Small LOCA with temporary loss of emergency core cooling (ECC) injection.
2.
Transient with temporary loss of all feedwater and the high pressure ECC system.
3.
Interruption of all AC electric power with failure of the auxiliary feedwater system.
BWR 4.
Transient with reactor isolation and temporary failure of all coolant make-up systems.
5.
Small LOCA with temporary failure of ECC injection.
6.
Transient with failure of reactor shutdown systems and interruption of ECC systems.
Table II.
Parametric Variations of a PWR Small-Break Scenario Rate of Timing of Rate of Steam /
Concurrent, H Releaset H Release Enthalpy Release Failures &
2 2
(1b/ min)
(lb/ min (millions Recoveries of Etu/ min))
2
- Starting at Time 10 of Uncovering of Top 600(1)
- Fans 30 of Core 3,600(6)
- Containment 100
- Prior to major
- 10,000(16)*
Sprays steam release
- All AC power 1,000
- Concurrent with
- Recirculation major steam release
- Following major steam release This high rate of steam release may accur for about 10 min. during ECC recovery.
tThese rates should be assumed to be constant during the period of release and represent release from the primary system to the contain-ment building.
10 Enclosure "D"
[7590-01]
due to uncertainties within a particular sequence.
The envelope of hydro-gen and steam source terms to the containment would then be provided to all licensees for use in subsequent analyses.
This approach would avoid the need for case-by-case sequence analyses using codes like MARCH and involving extensive iterative review of the MARCH analyses with the Commissicn.
The intent would be for the Commission to provide hydrogen and steam source terms generic to each reactor type (BWR or PWR) and let the licensees' and NRC's ensuing attention be on the containment analysis.
(The staff intends to publish for comment these gencric source term anal-yses during the comment period for this proposed rule.)
The Commission particularly welcomes comments concerning which of the above approaches is prefered as well as suggestions regarding improve-ments or other alternatives.
The proposed rule has also been modified to clarify the types of analyses required.
They can be grouped into four classes, depencling upon containment design, as follows:
1.
BWP,s with Mark 1 and II type containments are required to be inerted by the cc:rpsnion rule on inerted containments appearing elsewhere in this issue.
(See Table of Contents under NRC Rules and Regulations.)
There are no fe tner analyses required of these plants.
2.
Effective [one year after the effective date of the rule], or the date of issuance of a license authorizing operation above 5 percent of full power, whichever is later, analyses would be required for BWRs with Mark III type containments and PWRs with ice condenser type contain-ments to demonstrate that the installed hydrogen control system is ade-quate and will perform its intended function in a manner that provides adequate safety margins.
Analyses should also De performed to assess the effectiveness of alternative systems.
11 Enclosure "D"
[7590-01) 3.
Effective [one year after the effective date of the rule] or the date of issuance of a license authorizing operation above 5 percent of full power, whichever is later, additional analyses would be required for BWRs with Mark III type containments and PWRs with ice condenser type contain-ments, identical to that described under item 4, to show that safe shutdown will be asured and containment structural integrity maintained during degraded core accidents.
4.
Owners of all other containments would be required to perform and submit by [two years after the effective date of the rule] or the date of issuance of a license authurizing operation aoove 5 percent of full power, whichever is later:
(i) analyses to assure that during degraded core accidents containment structural integrity will be main-tained; and (ii) equipment survivability analyses to assure continued containment integrity and safe shutdown capability.
These degraded core accidents will be assumed to produce hydrogen releases tc the contain-ment resulting from the reaction of up to and including 75% of the fuel cladding surrounding the active fuel region with water for a range of time periods consistent with the accident scenarios analyzed.
The analyses required by this section serve two purposes.
- First, they support continued re.iance on the interim requirements of this rule.
Second, the results will be considered in a longer term rulemaking on degraded cores.
PAPERWORK REDUCTION ACT The proposed rule will be submitted to the Office of Management and Budget for clearance of the application requirements that may be appro-priate under the Paperwork Reduction Act (Pub. L.96-511).
Tne SF-83 12 Enclosure "D"
[7590-01]
"i.equest for C?earance," Supporting Statement, and related documentation submitted to OMB will be placed in the NRC Public Document Room at 1717 H Street NW., Washington, D.C. 20555.
The material will be available for inspection and copying for a fee.
REGULATORY FLEXIBILITY ACT In accerJar.ce with the Regulatory Flexibility Act of 1980, 5 U.S.C.
605(b), the Commission hereby certifies that this rule will not, if pro-mulgated, have a significant economic impact on a substantial number of small entities.
This proposed rule affects only the licensing and opera-tion of nuclear power plants.
The companies that own these plants do not fall within the scope of the definition of "small entities" set forth in the Regulatory Flexibility Act or the Small Business Size Standards set out in regulations issued by the Small Business Administration at 13 CFR Part 121.
Since these companies are dominant in their service areas, this proposed rule does not fall within the purview of the Act.
Accordingly, notice is hereby given that, pursuant to the Atomic Energy Act of 1954, as amended, the Energy Reorganization Act of 1974, as amended, and section 553 of title 5 of the United States Code, adnp-tion of the following amendments to 10 CFR Part 50 is contemplated.
PART 50--DOMESTIC LIriNSING OF PRODUCTION AND UTILIZATION FACILITIES 1.
The authority citation for.Part 50 reads as follows:
AUTHORITY:
Secs. 103, 104, 161, 182, 183, 189, 68 Stat. 936, 937, 948, 953, 954, 955, 956, as amended (42 U.S.C. 2133, 2154, 2201, 2232, 2233, 2239); secs. 201, 202, 206, 88 Stat. 1243, 1244, 1246 (42 U.S.C., 5841, 13 Enclosure "D"
[7590-01]
5842,5846), unless otherwise noted.
Section 50.78 also issued under sec. 122 68 Stat. 939 (42 U.S.C. 2152).
Sections 50.80-50.81 also 1
issued under sec. 184, 68 Stat. 954, as amended; (42 U.S.C. 2234).
Sec-tions 50.100-50.102 issued under sec. 186, 68 Stat. 955; (42 U.S.C. 2236).
For the purposes of sec. 223, 68 Stat. 958, 4:. amended; (42 U.S.C. 2273),
650.54 (i) issued under sec. 161i, 69 Stat. 949; (42 U.S.C. 2201(i)),
6950.70, 50.71 and 50.78 issued under sec. 1610, 68 Stat. 950, as amended; (42 U.S.C. 2201(o)) and the Laws referred to in Appendices.
2.
Section 50.44 of Part 50 is amended by adding the following paragraphs to paragraph (c) to read as follows:
550.44 Standards for combustible gas control system in light water cooled power reactors.
x (c)
(3)
(iii) Effective [one year after effective date of the rule], or the date of issuance of a license authorizing operation above 5 percent of full power, whichever is later, each boiling light-water nuclear power reacter with a Mark III type containment and each pressurized light-water nuclear power reactor with an ice condenser type containment, for which a construct. ion permit was issued prior to March 28, 1979, shall be pro-vided with an acceptable hydrogen control system justified by suitable programs of experiment and analysis.
The hydrogen control system must be capable of handling an amount of hydrogen equivalent to that generated from the reaction of 75% cf the fuel cladding surrounding the active fuel region (excluding the cladding surrounding the plenum volume) with water, 14 Enclosure "D"
[7590-01]
without loss of containment structural integrity (i.e., steel containments must meet the requirements of the ASME Boiler and Pressure Vessel Code,Section III, Division 1, Subsubarticle NE-3220, Service Level C Limits, except that evaluation of instability is not required, considering pres-sure and dead load alone.
Concrete containments must meet the require-ments of the ASME Boiler and Pressure Vessel Code,Section III, Division 2, Subsubarticle CC-3720, Factored Load Category, considering pressure and dead load alone.
These subsubarticles have been submitted for approval for incorporation by reference by the Director of the FEDERAL REGISTER.
A notice of any changes made to the material incorporated by reference will be published in the Federal Register.
Copies of the ASME Boiler and Pressure Vessel Code may be purchased from the American Society of Mechanical Engineers, United Engineering Center, 345 East 47th Street, New York, N.Y. 10017.
It is also available for inspection at the Nuclear Regulatory Commission's Public Document Room, 1717 H Street NW., Washing-ton, D.C.)
If the hydrogen control system relies on post-accident inerting, the containment structure must be capable of withstanding the increased pressure (A) during the accident, wnere it must not exceed Service Level C Limits or the Factored Load Category (as previously specified in this paragraph) and (B) following inadvertent full inerting that may occur during normal plant operations, where it must not exceed either Service Level A Limits (for a steel containment) or the Service Load Category (for a concrete containment).
Equipment required to maintain safe shut-down and containment integrity must be designed and qualified for the environment caused by post-accident inerting.
Furthermore, inadvertent full inerting during normal plant operations must not adversely effect systems and components needed for safe operation of the plant.
Modest 15 Enc 1csure "D"
[7590-0'13 deviations from these criteria will be considered by the Commission if good cause is shown.
(iv) Effective [one year after effective date of the rule] or the date of issuance of a license authorizing operation above 5 percent of full power, whichever is later, each boiling and pressurized light-water nuclear power reactor, for which a construction permit was issued prior to March 28, 1979, that does not rely upon an inerted atmosphere to con-trol hydrogen inside the containment, shall be provided with systems necessary to assure safe shutdown and maintain containment integrity that are capable of performing their functions during and after being exposed to the environmental conditions created by the burning (or local detona-tion) of hydrogen.
The amount of hydrogen to be considered is equivalent to that ger.erated from the reaction of 75% of the fuel cladding surrounding the active fuel region (excluding the claddir.g surrounding the plenum volume) with water.
(v) Analyses shall be performed and submitted to the Director of Nuclear Reactor Regulation for light-water nuclear power reactors, for which a construction permit was issued prior to March 28, 1979, to eval-uate the consequences of large amounts of hydrogen generated after the start of an accident (hydrogen resulting from the reaction of uo to and including 75 percent of the fuel cladding surrounding the active fuel region with water) including consideration of hydrogen control measures as appropriate.
Each analysis must include the period of recovery from the degraded condition.
The accident scenarios to be used in the analyses must be acceptable to the NRC staff.
The scope and implementation require-ments for the analyses for the various types of light-water nuclear power reactors are as follows:
16 Enclosure "D"
[7590-01]
(A) For each boiling light-water nuclear power recctor with a Mark III type containment and each pressurized light-water nuclear power reactor with an ice condenser type containment, analyses shall be performed that justify the selection of the hydrogen control system required by S 50.44 (c)(3)(iii).
These analyses shall be completed and submitted by [one year after the effective date of the rule], or tha aate of issuance of a license. authorizing operation above 5 percent of full power, whichever is later.
(B) For each light-water nuclear power reactor that does not rely upon an inerted atmosphere to control hydrogen inside the containment, analyses shall be performed to show that containment structural integrity as defined in 5 50.44(c)(3)(iii) will be maintained, and systems and com-ponents necessary to assure safe shutdown and maintain containment integ-city will be capable of performing their functions during and after being exposed to the environmental conditions created by the burning of hydrogen, includ'ng the effect of local detonations.
These analyses shall be com-pleted and submitted as follows:
for boiling light-water nuclear power reactors with Mark III type containments and pressuri[$d light-water nuclear power reactors with ice condenser type containments, by [one year after the effective date of the rule] or the date of issuance of a license authorizing operation above 5 percent of full power, whichever is later; for the other light-water nuclear power reactors requiring these analyses, by [two years after the effective date of the rule] or the date of issuance 17 Enclosure "D"
[7590-01]
of a license authorizing operation above 5 percent of full power, whichever is later.
Dated at Washington, D.C. this day of 1981.
For the Nuclear Regulatory Commission Samuel J. Chilk Secretary of the Commission 18 Enclosure "D"
6 a
ENCLOSURE E
NRC ADOPTS FINAL RULE ON HYDROGEN CONTROL FOR NJCLEAR POWER REACTORS; PROPOSES ADDITIONAL REQUIREMENTS The Nuclear Regulatory Commission is amending its regulations to improve methods of controlling hydrogen ganerated during nuclear power reactor accidents.
At the same time, the Commission also is considering additional amendments for hydrogen control capability for power reactors.
The accident at Three Mile Island 2 in March 1979 resulted in the release of radioactive material to the coolant system and the generation of hydrogen from fuel cladding-water reaction well in excess of amounts required to be assumed for reactor design purposes.
As part of its response to that accident, the NRC has initiated a long-term rulemaking proceeding to determine to what extent nuclear power reactors should be designed to deal effectively with damaged and melted fuel accidents.
In the interin., the Commission has determined that changes covered by this rule are of such safety significance that they should be implemented pending completion of the long-term rulemaking.
Consequently, the Commission has set out soecific hydrogen control requirements in a FEDERAL REGISTER notice published on The new rules require that:
boiling water reactors having Mark I or II ccntainments inert the containment atmosphere (remove oxygen) to provide protection against hyo;ogan burning and explosions during accidents involving generation of large mounts of hydrogen.
1 Enclosure "E"
nuclear power reactors which % oc genting nave the capability to install external hydrogen recombiners so tnat means other than venting would be available for hydrogen control.
The amendments to Part 50 of NRC regulations will become effective 30 days after publication in the FEDERAL REGISTER.
The additional amendments being considered by the Commission that also would improve hydrogen control capabili+'s: wouIdrequirethat:
bciling water reactors having Mark III containments and pressurized water reactors with an ice ;cndenser-type containment be provided with a system capable of han>2iing an amount of hydrogen--equivalent to that which would be generated if tnere were et least a 75% fuel cladding-vatar reaction--withcut loss of containment integrity.
each boiling uter re2ctor and pressurized water reactor that does not rely on an inerted atmosphere for hydrogen control be provided with safety systems-needed for assuring safe shutdown and maintaining containment integ-rity--that can fun: tion after the burning of substantial amounts of hydrogen.
analyses be performed for the recctor categories mentioned above to justify the hydrogen control systems selected and to assure containment struc-tural integrity and survivability cf needed sr.foty systems during a hydrogen burn.
The proposed amendments to Part 50 are being published in the FEDERAL REGISTER on Interested persons are invited to submit written cotments or suggestions for consideration in connection with the proposed amendments to the Secretary of the Commission, U.S. Nuclear Regulatory Commission, Washington, D.C. 20555, Attention:
Docketing and Service Branch, by 2
Enclosure "E"
e d
e EllCLOSURE A 6
"*/
UNITE D STATES
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It.. -
E v.e.: mt.
or. 0 :.2:sts ACE b - Mineeq; /
ven;cn g,' :.L-p j April 27,1951 Cys:
Dirch Cornell OF F ICE OF THE p
stCRETARY
,ielshman r
Denton Stello Shapar MEMORANDUM FOR: Iilliam J. Dircks, Executiv Alirector Vollmer for Operations FROM:
Samuel J. Chilk, Secretar Q
l
SUBJECT:
STAFF REQUIREMENTS - BRIEFINGJON EFFECTIVE INTERIM AMENDMENTS TO 10 CFR 50 CN HYCRD3EN DONTROL AND CERTAIN DEGFADED CORE CONSIDERATIONS (SECY-Sl-245), 10:00 A.M., THURSDAY, APRIL 23 1981, COMMISSIONERS' CONFERENCE ROOM, D.C. OFFICE (OPEN TO PUBLIC ATTENDANCE)
The Co.=ission was briefed by staff on the proposed interim rule on hydrogen control and certain degraded core considerations.
Co:missioner Gilinsky would like to hve the staff explain to him why the evaluation of instability is not reouired for steel containments (reference pages 21-22 of Enclosure C to SECY-81-245).
(NRR)- Suspease 5-15-81 The Comission agreed to deletion of the last sentence of the paragraph ending on page 22 of Enclosure C to SECY-81-245 from the proposed rule.
The Comission reached no decisien at the meeting. The Chairman indicated that further consideration would be given to the proposal at a Comission meeting at a later date.
cc:
Chairman Hendrie Commissioner Gilinsky Comissioner Bradford Commissioner Ahearne Comission Staff Offices Public Document Room eP Q
<:g1,%[l I f f W Enclosure "A'
O i
ENCLOSURE B
to
. _.,. c :. r.;.
REFER 10:
M510r.304
- pf
- a r cg'o UNITE D STATES A C TI O.'
- n l'h N fJUCLEAR REGULATORY COMMISSION 5.ghgdj r
Lys:
r: s m ss mcr on. o.e. 20sss wfMtei O
.7 g
f May.8, 1981 nehm Eisenhut Ol s hinski orFACE OF THE ggy,73 gg I',i r o cu e SECRET ARY
< FladEf.ifi Shapar f
MEMORANDUM FOR: VUilliam J. Dircks, Executiv Director for Operations S tello Besaw FROM:
Samuel J. Chilk Secret y/
Fel ton Philips
SUBJECT:
STAFF REQUIREMENTS - PROPOS D RULE ON OL APPLICATIONS
~
(SECY-81-246) AND INTERIM BMFNDMENTS Gr1 HYDROGEN CONTROL,(SECY-Bi-245) 10:10 A.M., THURSDAY, APRIL 30, 1981, COMMISSIONERS' CONFERENCE ROOM, D.C. JFFICE (OPEN TO PUBLIC ATTENDANCE)
The Commission, by a vote of 3-1 (Commissioner Bradford dissenting), approved a Federal Register Notice as modified below seeking comment on a proposed rule that incorporates into 10 CFR Part 50 a set of THI-2 requirements for operating license applications.
The Commission requested that the Federal Register Notice be modified:
1.
to indicate in the Statement of Consideration that a similar rulemaking with respect to operating reactors will be published for comment in the near future; 2.
to inc.rpdate those items on the attached errata sheet that was distributed by staff at the meeting; and 3.
to solicit comment on the effective date and'its application to pending proceedings.
The Commission requested that the Federal Register Notice be sent te all known interested persons.
Connissioner Bradford dissented from the publication of the orcocsed rule on the crounds that the subiect matter was too broad to be dealt with coherentiv and effectivelv in a sincie rulemakinam.
Attachment:
As Stated cc:
Chairmar Hendrie
]
Commissioner Gilinsky Commissioner Bradford Commissioner Ahearne Commission Staff Offices Public Document Room bt "rg J,4 f p 1 pif SM Enclosure "L"
4 e
ENCLOSURE C e