ML19276H403
| ML19276H403 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/23/1972 |
| From: | US ATOMIC ENERGY COMMISSION (AEC) |
| To: | US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML19276H402 | List: |
| References | |
| NUDOCS 7910180696 | |
| Download: ML19276H403 (3) | |
Text
.-
's ENCLOSURE "O.
1 MEETING
SUMMARY
THREE MILE ISLAND UNIT 1 On May 15, 19 72, members of the staff of RO made a presentation to members of the staff of L that provided detailed and updated information of the status of the ring-girder of the Three Mile Island Nuclear Generating Station Unit 1.
The presentation was based on an inspection of the f acility on May 4,1972, by S. Folson, T. Varella, L. Beratan and H. Schierling.
The presentation included a brief summary of the events that led to the defects along the entire ring-girder.
The present status of the ring-girder is as follows :
1.
North Section--Segments with only upper or lower tendon conduits and bearing plates have been completely repaired in accordance with procedures documented by the applicant.
2.
North Section--Segments with upper and lower tendon conduits and bearing plates have been excavated extensively into solid and sound concreta.
For this purpose all reinforcing bars were cut The applicant intends to proceed with the repair by replacing out.
reinforcing bars using cadweld splices.
3.
South Section--Dirt pockets were recently uncovered along the entire construction joint between lif tc 3 and 4 on the surface of the ring-girder.
These pockets were cleaned out and two-inch diameter bore cores have been taken up to a depth of approximately 3.5 feet.
The as-built location of the constructicn joint varies by as much as one foot from the design location.
Concrete voids exis t parti-cularly around the bearing plates and along the ccnstruction joint.
However, the voids along the south section are far less extensive than those that were uncovered along the north section.
I pointed out that the repair procedures presently employed on the north section were discussed between the staf f and the applicant, that the applicant documented the repair procedures (" Report on Centainment Building Ring-Girder Construction and Repair," dated December 1,1971, and an addendum to that report dated January 21, 1972) and that the staf f found these repair procedures adequate if certain provisiens were included.
A letter to this ef fect was sent to the applicant on March 1,1972, in which we requested the applicant to make a written commitment to include these provisions.
As of today, we have not received such a written commitment. Our review of the preoosed reoair nrocedures was base.1 c; the a.;stmption : -
- _ 3 _ :"
_::ica f th;. -:-::r22_
is defect-f ree as was indicatec oy cae applicant in our meetings and in his submit tals.
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In an extensive discussien, it was questioned whether the observed defects resulted frem inadequate design, code violation, poor work-manship, or inadequate quality control.
It was the consensus that poor workmanship and ineffective quality control were probably the major causes.
The need for additional precautions in pouring the ring girder concrete for containments of similar design (Gilbert Associates) was reviewed.
It was concluded that Regulatory Operations would take appropriate steps to alert and inform the applicant of the Crystal River plant with respect to the difficulties experienced at Three Mlle Island.
With regard to further resolution of the problem at Three Mile Island it was agreed that the applicant be requested by letter to provide (1) the above indicated written commitment to include certain provisions in his repair procedures and (2) a complete evaluation of the repaired ring-girder with reference to the design requirements. A letter including this request was sent to the applicant on May 16, 1972.
S. Folsom indicated that the repair work might further delay the fuel loading date and would involve additional expenditures on the order of $1,000,dOO.
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ENCLOSURE NO. 2 ATTENDANCE LIST DRO - HQ R. H. Engelken DRO - HQ J. B. Henderson G. W. Reinmuth DRO - HQ DRO - HQ 1
C. Gower D. E. Whitesell DRO - HQ DRO - HQ L. L. Beratan DRO - I S. A. Folsom DRS - I A. A. Varella DRO - II W. B. Swan L
R. W. Klecker L
A. Schwencer L
K. Kniel L
A. L. Gluckmann L
K. Shewnaker L
F. P. Schaver L
H. Schierling 1420 349