ML15260A018
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 February 15, 1980 Docket Nos:.- 269, 50-270, 50-287, 50-289, 50-302, 50-312, 50-313, 50-346 MEMORANDUM FOR:
Z.R. Rosztoczy, Chief Analysis Branch Division of Systlems Safety FROM:
R.A. Capra, B&W Project Manager, Standardization Branch, Division of Project Management THRU:
Kane, Acting Chief, Standardization Branch, LA'Division of Project Management
SUBJECT:
OUTSTANDING ITEMS ON B&W OPERATING PLANTS ASSOCIATED WITH WORK REQUESTED BY THE BULLETINS & ORDERS TASK FORCE As you know, several outstanding items still remain regarding the B&W operating plants.
Some of these items have been responsed to by the B&W licensees and need to be reviewed by the Analysis Branch.
Some of these items may be covered in the TMI-2 Task Action Plan; however, since we are actively engaged in hearings on Rancho Seco and TMI-1, I don't think we can afford to delay reviewing the licensees' submittals.
The Rancho Seco hearing is scheduled to begin on February 26, 1980 and the TMI-1 restart proceeding is in the discovery stage at this time.
Enclosure (1) identifies four items for which we have received responses to our requests for additional information. In addition, Enclosure (1) also provides a status of three additional items for which we will receive responses within the next few weeks.
I will forward additional information on these items as they are received.
If you have any questions, please contact me on X-27745.
Robert A. Capra, 8&W Project Manager
Enclosures:
Standardization Branch 1-Status of outstanding items Division of Project Manager 2 through 8 (identified in Enc1 1) cc:
(7
- 0. Ross H. Silver R. Tedesco G. Mazetis R. Reid P. Norian
- 7. Novak S. Lewis
LNLL{J@6L (I )
B&W OPERATING PLANT OPEN ITEMS FROM B&OTF WORK (ANALYSIS BRANCH)
SUBJECT CONC RNS REGARDING POSSIBLE VOIDING IN THE RCS DURING ANTICIPATED TRANSIENTS Status:
Letter from R. Reid to all B&W Operating Plants dated 01/09/80, requested that the B&W I fens.ees evaluate concerns expressed by D. Hunter (IE-RIII) regarding possible void formation taing place on the hotter regions of the reactor vessel during anticipated transiets.
Responses from three of the utilities have been received (Oconee,.SMUD, and Davis-Bss.
Each response forwards a generic report prepared by B&W entitled, "POTENTIAL REACTOR SYSTEM VODING DOURING ANTICIPATED TRANSIENTS," January 1980.
Action:
It is requested that the Analysis Branch take the lead in reviewing this document in a timely fashion. The California Energy Commission has appended R. Reid's letter Of 01100 leter to its testimony in the Rancho Seco Hearing as evidence that the staff is oncerndd a~b6Ut the safety of the B&W operating plants. A copy of this report is included As Endosure (2) b his memorandum.
- 2. BENCHMARK ANALYSIS OF SEQUENTIAL AFW FLOW TO THE OTSG USING CRAFT-2 with 3-NODE OTSG REPNRSE TION Status:
Lettr from D. Ross to all B&W Operating Plants dated 08/21/79, identified the o1tstinding items related to the B&W Small Break Analysis. One of the items listed requested that the licensees provide a benchmark analysis of sequential AFW flow to the OTSGs following a loss of ain feedwater.
An analysis was provided in a letter from J. Taylor (B&W) to R. Mattson (NRC) dated 06/15/79.
However, in this analysis the TRAP-2 code with a 6 node OTSG. Since al1 small brk a analyses presented to the NRC were performed using the CRAFT-2 code with a 3 node OTSG mode1 we required that a benchmark analysis also be performed using the CRAFT-2 code.
Responses from three of the utilities have been received (Oconee, SMUD, and Davis -esse).
Each response forwards a generic analysis prepared by B&W.
Action:
Review response and advise me as to its acceptability. A copy of this response is E iosure (3).
- 3. IMPACT OF RGP SEAL DAMAGE AND LEAKAGE FOLLOWING A LOCA Status:
Letter from R. Reid to all B&W Operating Plants dated 11/21/79, requested that fhe B&W licensees evaluate the impact of RCP seal damage and leakage due to loss of seal, ooling on loss of offsite power. Recommendation 2.6.2.f of NUREG-0565 also requested that licesees should provid an analysis of the limiting small break LOCA with subsequent RCP seal failure, if d'amage cannot be precluded.
Responses from four of the utilities (Oconee, Rancho Seco, Crystal River 3, and Davis-Besse) have been received. The response from ANO-1 is expected shortly.
Action: Coordinate with MEB and advise me of your joint assessmient.
Copies of the respohses are included ad Fnr Purp (4) thrainh (7).
LNCLOSUR I) page 2
- 4. MECHANICAL EFFECTS OF SLUG FLOW ON OTSG TUBES Status:
Letter from R. Reid to All B&W Operating Plants dated 11/21/79, requested licensee to evaluate C. Michaelson's concern reguarding the mechanical effects of induced slug flow oni OTSG tubes caused by the transitioning from solid natural circulation to reflux 66o111ng and back again.
Respohses have been received from three of the utilities (Oconee, Ranco Seco, a" C r stal River 3).
B&W prepared a generic response for this concern.
ActiOn:
Review the generic response and advise me of its acceptability.
A copy of this s"p6nse is included as Entcosure (8).
STATUS OF ADDITIONAL OPEN ITEMS FOR WHICH WE HAVE NOT RECEIVED RESPONSES
Letter from D. Ross to All B&W Operating Plants dated 08/21/79, identified the outstandinh items retated to the B&W Small Break Analysis.
One of these items was to perform.an analysis of the RCS response to a SBLOCA which leads to repressurization of the RCS to the PORV setpoin t (2 Break LOCA). In November 1979, the licensees provided a qualitative assessrient of this accident, with a commitment to provide the detailed quantitative assessment/analysis in February 1980.
8W has completed the analysis and forwarded it to the licensees for review. We should receive this analysis in about 1 week.
- 6. THERMAL-MECHANICAL REPORT ON CONDITIONS IN THE REACTOR VESSEL DURING LONG-TERM RECOVERY FROM A SBLOCA Status: Letter from D. Ross to All B&W Operating Plants dated 08/21/79, identifed the need for the licensees to provide a detailed analysis of the thermal-mechanical conditions in the reactor vessel during recovery from small breaks with an extended loss of all feedwater to show reactor vessel integrity was matained during long-term feed and bleed operations.
B&W has delayed the submissiondfithis repbrt several times.
Presently B&W does not intend on completing this analysis until the March 1980 time frame.
B&W states that this additional time is needed in order to get more detailed and plant specific material and weld information from the utilities in order to make the report meaning ful.
1 1Ld (I) pa ye 3 STATUS OF ADDITINAL OPEN ITEMS FOR WHICH WE HAVE NOT RECEIVED RESPONSES (CONTINUE
- 7.
AUTOMATIC RCP TRIP FOR LOCA CONDITIONS Status:
On 12/17-12/18/79 we sent letters to the B&W licensees giving preliminary design approval to proceed with final design and procurement of equipment necessary to provide a safety-grade automatic RCP trip system for LOCA conditions. The system approved would use a ESFAS actuation signal coincident with low RCP current/power. However, the preliminary design approval was based on the assumption that the licensees would be required to experime.-ntally ve'ify the use of RCP. current/power as a valid and reliable indication of voiding in the RCS.
We have received notification from the B&W licensees that this verification may be too expensive.
Therefore, the licensees are discussing other alternative solutions.
The licenssees have requested until 02/29/80 to find a solution.
At that time it is anticipated that a meeting with the Owners' Group will be needed to once again discuss this issue.