Followup Actions Resulting from the NRC Staff Reviews Regarding The Three Mile Island Unit 2 Accident (Generic Letter 79-40)


                               UNITED STATES 
                          WASHINGTON, D.C. 20555 




Over the past several months following the Three Mile Island accident, the 
NRC staff has been conducting an intensive review of the design and 
operational aspects of nuclear power plants and the emergency procedures for
coping with potential accidents. The purpose of these efforts was to 
identify measures that should be taken in the short-term to reduce the 
likelihood of such accidents and to improve the emergency preparedness in 
responding to such events. To carry out this review, efforts within NRR were 
established in four areas: (a) licensee emergency preparedness, (b) operator 
licensing, (c) bulletins and orders followup (primarily in the areas of 
auxiliary feedwater system reliability; loss of feedwater and small break 
loss-of-coolant accident analysis; emergency operating guidelines and 
procedures) and (d) Short-Tern Lessons Learned. 

It is the purpose of this letter to set forth NRR's requirements established
to date as a result of those efforts. Additional requirements may be 
developed as NRR's Lessons Learned Task Force completes its Long-Term 
Requirements. In addition, Commission review of the results of other 
investigations, including the Presidential Commission and the NRC's Special 
Inquiry Group, can be expected to load to additional requirements. 

     Lessons Learned Task Force Report 

     The principal element of the staff activities listed above is contained
     in the report titled, "TMI-2 Lessons Learned Task Force Status Report 
     and Short-Term Recommendations" (NUREG-0578), a copy of which was 
     previously sent to you.  The Task Force report contains a set of 
     recommendations to be implemented in two stages over the next 16 months
     on operating plants.  The Task Force recommended 20 licensing 
     requirements and three rulemaking matters in 12 broad areas. 

     The Advisory Committee on Reactor Safeguards has completed its review 
     of the Task Force report.  The several public meetings of the ACRS 
     subcommittee on TMI-2 and the public meeting of the full committee 

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     on August 9 provided an opportunity for the presentation and discussion
     of public comments on the report. The ACRS letter of August 13, 1979 to
     Chairman Hendrie states that the Committee agrees with the intent and 
     substance of all the Task Force recommendations, except four upon which
     the Committee offered constructive comments to achieve the same 
     objectives articulated by the Task Force.  The Committee also noted 
     that effective implementation will require a more flexible, perhaps 
     extended, schedule than proposed by the Task Force. A copy of the ACRS 
     letter is provided as Enclosure 1. 
     After considering all comments received, we have concluded that the 
     following actions are appropriate for operating nuclear power plants. 

     (a)  The staff will be proposing a new rule on a Limiting Condition of 
          Operation to require plant shutdown for certain human or 
          procedural errors, particularly those which are repetitive in 
          nature. As such, no action is required on your part at this time. 
     (b)  At the present time we are delaying efforts regarding proposed 
          rulemaking on both the inerting requirements for Mark l and II BWR
          containments, and the requirement regarding hydrogen recombiner 
          capability; accordingly, no action is required on your part at 
          this time. 

     (c)  The ACRS comments on the shift technical advisor have resulted In 
          our reassessment of the possible means of achieving the two 
          functions which the Task Force intended to provide by this 
          requirement. The two functions are accident assessment and 
          operating experience assessment by people onsite with engineering 
          competence and certain other characteristics. We have concluded 
          that the shift technical advisor concept is the preferable 
          short-term method of supplying these functions.  We have also 
          concluded that some flexibility in implementation may yield the 
          desired results if there is management innovation by individual 
          licensees.  We have prepared a statement of functional 
          characteristics for the shift technical advisor that will be used 
          by the staff in the review of any alternatives proposed by 
          licensees. A copy is provided as Enclosure 2. 

     (d)  Three additional instrumentation requirements for short-term 
          action were developed during the ACRS review of NUREG-0578. These 
          items relate to containment pressure, containment water 

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          level and containment hydrogen monitors designed to follow the 
          course of an accident. Descriptions of these items are provided in
          Enclosure 3. 

     (e)  An additional requirement following issuance of NUREG-0578, which 
          concerned a remotely operable high point vent for gas from the 
          reactor coolant system, was developed. A description of this 
          requirement is provided in Enclosure 4. 

     (f)  The Lessons Learned Task Force has compiled a set of errata and 
          clarifying comments for NUREG-0578. It Is provided as Enclosure 5.

     Following our review of each of the proposed Task Force requirements, 
     ACRS review, and comments received we have concluded that all operating
     reactor licensees should begin to implement the actions contained in 
     NUREG-0578, as modified and/or supplemented by items (a) through (f) 
     above, as soon as possible. Accordingly, please submit within 30 days 
     of receipt of this letter, your commitment to meet these requirements 
     on the implementation schedule contained in Enclosure 6.  The 
     implementation dates for the Commission rulemaking actions a those 
     deferred actions, identified above, will be established later. 

     Regarding implementation of these topics for Systematic Evaluation 
     Program (SEP) plants that are part of the SEP, we have determined that 
     implementation of these topics should not, in general, wait for final 
     resolution of the SEP. For good cause shown, such as interaction with 
     an SEP topic resolution, implementation delay may be justifiable on a 
     selected issue. 

     Other Review Areas 

     Enclosure 7 outlines the requirements developed to date resulting from 
     the staff's Emergency Preparedness Studies. Enclosure 8 provides the 
     implementation schedules for the emergency preparedness requirements 
     which, you will note, includes three of the Lessons Learned Topics. We 
     also require that you provide commitments to comply with each of the 
     requirements of Enclosure 7 in accordance with the implementation 
     schedules shown in Enclosure 8. Such commitments should be included in 
     your letter due in 30 days of receipt of this letter. Further, the 
     Commission has initiated a rulemaking procedure, now scheduled for 
     completion in January 1980 in the area of Emergency Planning and 
     Preparedness. Additional requirements are to be expected when 
     rulemaking is completed and some modifications to the emergency 
     preparedness requirements contained in this letter may be necessary. 

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     Enclosure 9 outlines the staff recommendations concerning improvements 
     in the area of operator training and are provided for your information.
     Those recommendations are undergoing Commission review, and are 
     expected to be adopted as requirements in the near future. Further 
     Commission review in the areas of operator training and qualification 
     can be expected to result in substantial additional requirements. 
     A number of other related actions on your facility have been underway 
     for some time under the direction of the NRR Bulletins and Orders Task 
     Group. Each licensee will receive additional guidance from this group, 
     particularly related to auxiliary feedwater systems and small break 
     LOCAs, in the near future.  Your activities should continue in these 
     areas, as all the mentioned activities are meant to complement one 

The measures discussed above represent a set of requirements that should be 
implemented at this time. As stated earlier, other requirements may follow 
in the future. To assist in explaining in more detail each of these 
requirements, the NRC will hold regional meetings during the week of 
September 24, 1979, similar to those held for Emergency Preparedness. 
Attached as Enclosure 10 is s copy of the Federal Register Notice announcing
such meetings. 

If you have any questions regarding these actions, please contact the NRC 
Project Manager for your facility. 


                                   Darrell G. Eisenhut, Acting Director 
                                   Division of Operating Reactors 

1.   ACRS Ltr: Carbon to Hendrie dtd 8/31 /79
2.   Alternatives to Shift Technical Advisor 
3.   Instrumentation to Monitor Containment conditions
4.   Installation of Remotely Operated High Point Vents 
          in the Reactor Coolant System
5.   NUREG-0578 Errata 
6.   Implementation Schedule
7.   Requirements for Improving Emergency Preparedness 
8.   Emergency Preparedness Improvements - Implementation Schedule 
9.   Improvements in Operator Training 
10.  Federal Register Notice


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