ML19309G476
| ML19309G476 | |
| Person / Time | |
|---|---|
| Site: | Bailly |
| Issue date: | 04/10/1980 |
| From: | Rolonda Jackson Office of Nuclear Reactor Regulation |
| To: | Rubenstein L Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8005070025 | |
| Download: ML19309G476 (7) | |
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UNITED STATES y'
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NUCLEAR REGULATORY COMMISSION
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E WASHINGTON, D. C. 20555
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APR 10 1980 MEMORANDUM FOR:
L. S. Rubenstein, Chief
' ight Water Reactors Branch No. 4, DPM FROM:
x b -+ E. Jackson, Chief
.anch, DSS Geost...
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SUBJECT:
DRAFT REGULATORY STAFF POSITIONS AND DRAFT REQUESTS FOR INFORMATION PLANT NAME: Bailly Nuclear 1 LICENSING STAGE:. Post CP DOCKET NUMBER: 50-367 TAC NUMBER: 4764 MILESTONE NUMBER: R-18 RESPONSIBLE BRANCH: LWR-4; M. D. Lynch, LPM REVIEW STATUS: Awaiting h,'olicant's Response Attached to this memorandum are draft Regulatory Staff Positions and draft.
Requests for Information for the Bailly Plant.
In accordance with our previous.
commitment to the applicant (Meme 0. Thompson to R. Jackson, dated March 6, 1980, subject: Site Visit to Bailly wita COE Detroit) please transmit this information to the applicant before April 14, 1980 in preparation for our meeting with the applicant on April 17, 1980. Our positions and questions may be modified as a result of the meeting discussions.
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ob$r D j ks ',' Cii Geosciences Br 'ch Division of/
tems Safety
Attachment:
As stated cc: w/o attachment.*
H. Denton R. Mattson F. Schroeder D. Ross D. Vassallo cc: w/ enclosure See next page
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i l 4 cc: w/ attachment J. Knight S. Varga R. Jackson D. Lynch L. Heller i
F. Schauer i
J. Ma G. Lear E. Gallagher P. Barrett
- 0. Thompson N. Gehring, COE Detroit 1
M. Davisson, Consultant W. Hall, Consultant PDR j
Local PDR 4
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PLANT NAME: Bailly Nuclear 1 LICENSING STAGE:. Post CP DOCKET NUMBER: 50-367 TAC NUMBER: 4764 RESPONSIBLE BRANCH: LWR-4; M. D. Lynch, LPM MILESTONE NUMBER: R-18 REVIEW STATUS: Awaiting Applicant's Response Prepared by: Dr. Owen 0. Thompson, Geosciences Branch, DSS Draft Regulatory Staff Positions 1.
The staff and its consultants require that all piles must be driven to a final resistance of at least 60 blows for the last 3 inches (60/3").
2.
All indicator piles and all piles redriven after heave must meet the 60/3" criterion. Thus, indicator piles not now meeting this criterion must be redriven.
3.
After the indicator piles have been redriven to the 60/3" criterion, the NRC must be provided with and approve the applicant's evaluation which shcws that there is no inclination towards relaxation of piles and concomitant reduction in capacity. The redriving, evaluation of redriving,and commencement of production pile driving may be done in selected areas before redriving is completed.
4.
During driving and redriving, sample data must be submitted to NRC as production proceeds. Also, contours of the bearing layer must be continually re-established.
5.
The densification of the so-called pre-construction areas by pipe piles must be completed before additional production piles are driven in these areas. The licensee's evaluation of the densification program must be reviewed and approved by NRC before production piles are installed in the pre-construction areas.
To tha extent possible, production piles should be installed in the pre-l construction areas before other' areas.
6.
The specific pile tolerances of 3 inches in location, 10 deg. in rotation and 2% in piumb are acceptable. The staff also wili accept greater tolerances on up to 10% of production piles, contingent upon approval by the Chief Structural Engineer and concurrence by NRC.
In such cases a Non Conformance Report will be written by the QA management and the deviation approved by the Chief Structural Engineer. Deviations greater than 12 inches in location, 20 deg. in rotation or 4% in plumb will not be acceptable to NRC under any foreseeable circumstances.
7.
FieldsplicesinadjacentpilesmustbeseparatedYerticallybyadistance of at least 3 ft.
8.
Field bending of reinforcing steel will not be permitted except as allowed by approved codes.
9.
Piles which have been driven greater than 10 ft. below grade may not be pulled. Such piles shall cut off at least 12 inches below proposed bottom of mat elevation, and abandoned. When piles are pulled, if the pile does not pull cleanly, the disturbed soil must be recompacted. Recompaction specifications must be included in the construction documents.
- 10. A qualified inspector, as described in the QC manual, must be provided for eachpiledrivingrigwhilepilest.ebeingdriYen. The qualifications of the inspector (s) must be submitted to NRC for approval prior to pile driving.
- 11. Checking pile heave at a distance of 3 pile rows is not adequate -- this distance could be as little as 10 ft. Pile heave checks should extend adistanceofatleast50ftfromthepilebeingdriYen. This criterion i
l also applies to redriven piles. Thus, it is poss'ible that piles could require redriving more than once.
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. 12. Heave on the densification (pipe) piles must be monitored as for production piles.
- 13. Settlements of all portions of the foundation mat must be monitored during construction. At least four (4) permanent bench marks must be installed outside the construction area and anchored into rock. Settlement readings shouldprohidedocumentationofdifferentialsettlementsoccurringatsignificant stages of foundation construction.
- 14. The elevations of the permanent bench marks must be determined prior to the start of pile driving.
- 15. The long-term capacity of piles must be established. This can be done by performing load tests in which the maximum load (twice dead load plus live load) is held for at least 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> or until the rate of settlement is less than 0.01 inches per day. At least two (2) such tests should be made. Details of the proposedlong-termloadtestsmustbesubmittedtoNRCforourrehiewandapprohal.
- 16. Load tests as described in the QC manual must be made on production piles. The load tested piles must include a) atleast1pilewithType"A"drihingrecord(rapidincrease in driving resistance near final penetration) b)atleast1pilewithType"B"drihingrecord(slowincreaseindriving resistance up to final penetration) c) at least 2 piles in preconstruction areas d) at least 2 lateral load tests
(
e) at least 2 uplift load tests f)atleast2pilesredrihenafterheahing g) at least 2 piles tested for long-term settlement as in paragraph 15 above.
. The piles tests must be performed throughout the period of pile installation.
When appropriate, one pile may be used for more than one of the above tests.
The basis for selecting the piles to be tested must be submitted to NRC and approved by the staff. Additional tests may be required depending on the results of the initial tests.
- 17. Details of the cushion behavior must be included in the pile driving records.
- 18. Provide a comitment to stop construction and evaluate existing conditions if unusual or potentially detrimental conditions are encountered during pile foundation construction.
Oraft Reauests for Information 1.
Provide the proposed pile driving sequence, with consideration of positions 2 and 3, above. Also, provide detailed site and pile location plans, which show the pile identifications.
2.
Describe the proposed sequence of construction for foundations.
In your response include excavating, pile driving, backfilling to matsubgrade,matconstruction, dewatering,andothersignificantactiYities.
Also consider the following:
a) closely spaced piles will require special backfilling and compaction procedures b)pilesonornearconstructionslopeswilltendtomohetowardtheslope c) temporary sheeting and shoring details, if applicable, will need to be reviewed by NRC d) piles driven from an elevation above fir.al' grade will be subject to surcharge which will not be present during plant service.
l 3.
Provide the staff with copies of the QA/QC manual which will be used for construction. We believe that the issue submitted July 14, 1978 (R. Bohn, Nipsco, to R. Boyd, NRC) has ueen revised, i
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,o 4.
Provide the densification (pipe) pile placement plan. Describe, or provide a reference to the methods to be adopted which will show that the preconstruction areas have been adequately densified by the pipe pile installations.
5.
The staff considers it necessary to have a qualified NRC pile inspector on site during pile driving. The staff and its consultants also needs to witness typical and critical items of foundation construction. Commit to provide appropriate support facilities and services on site for these activities.
6.
Provide details of the settlement monitoring program which meets the demands of position 13, above.
7.
In the indicator pile program, piles were cased from ground surface down to proposed mat subgrade elevation in order to eliminate frictional resistance in this zone. However, the surcharge effects (increased effective confining pressures) on the p iles at lower depths were present on indicator piles but will not be present during plant service. Provide analyses and calculations which show that after removal of the surcharge loading the production piles will haveanadequatefactorofsafetyinserhice.
,8.
If the flanges of the piles are deformed during driving, the reduction in effective butt area may result in driving stresses exceeding the pile butt yield stress. Thus, the effective driving energy reaching the pile may be reduced.
Provide criteria with justification which will ensure that during the last 5 ft of driving the pile butts are trimmed if the flanges at the butt are excessively deformed.
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