ML20094F666
| ML20094F666 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 08/08/1984 |
| From: | Woolever E DUQUESNE LIGHT CO. |
| To: | Knighton G Office of Nuclear Reactor Regulation |
| References | |
| 2NRC-4-117, NUDOCS 8408130005 | |
| Download: ML20094F666 (7) | |
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'Af 4 )787-5 41 (412)923 1960 Nuclear Construction Division Telecop (412) 787-2629 Robinson Plaza, Building 2, Suite 210 Pittsburgh, PA 15205 August 8, 1984 United States Nuclear Regulatory Conunission Washington, DC 20555 ATTENTION:
Mr. George W. Knighton, Chief Licensing Branch 3 Office of Nuclear Reactor Regulation
SUBJECT:
Beaver Valley Power Station - Unit No. 2 Docket No. 50-412 Response to Draf t SER Open Item No.177 Gentlemen:
The response to the NRC Gect echnical Engineering Section's Draft SER Open Item No.177 is provided in Attachment 1.
The associated revision to FSAR Section 2,5 /.13 is provided in Attachment 2.
DUQUESNE LIGHT COMPANY By p J 7 Wdolever vice President JD0/wjs Attachments Ms. M. Ley, Project Manager (w/s) cc:
Mr. E. A. Licitra, Project Manager (w/a)
Mr. G. Walton, NRC Resident Inspector (w/a)
SUBSCRIBED AND RN TO BEFORE ME THIS
/ 4 DAY OF esug 1984.
la w&J K
/
Notary Public ELVA G. LESONDAK, NOTARY PUBLIC ROBINSON TOWNSHIP, ALLEGHENY COUNTY g}
MY COMMISSION EXPlRES OCTOBER 20,1986hg 1 1 h
8408130005 840008 DR ADOCK 05000412 PDR
Unitsd Stctss Nuclocr R3gulctory Commiosien Mr. Cacrgs W. Knighton, Chisf Page 2 COMMONWEALTH OF PENNSYLVANIA )
)
SS:
COUNTY OF ALLEGHENY
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On this 7 day of my
/((
, be fore me, a A
Notary Public in and for said Comn[nwealth and County, personally appeared E. 'J. Woolever, who being duly sworn, deposed and said that (1) he is Vice President of Duquesne Light, (2) he is duly authorized to execute and file the foregoing Submittal on behalf of said Company, and (3) the statements set forth in the Submittal are true and correct to the best of his knowledge.
4
~L Notary Public ELVA G. LESONDAK, NOTARY PUBLIC ROBINSON TOWNSHIP, ALLEGHENY COUNTY MY COMMISSION EXPIRES OCTOBER 20,1986 f.
-ATTACHMENT 1 Draft SER Open Item No. 17 7 (Section 2.5.4.3.3):
Settlement Monitoring Program:
The applicant must include, in the forthcoming anendment of the FSAR, the following information:
..3.
- A commitment to nonitor the settlements of all Category I struc-tures throughout the plant life.
Response
Refer to revised FSAR Section 2.5.4.13 (Attachment 2).
This revision will be incorporated into a future FSAR amendment.
ATTACRMENT 2 BVPS-2 FSAR L
h Eleven borings performed after the final densification program indicated that the densification requirements had been achieved. The
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given on Figure 2.5.4-32 and summary plots of boring locations are p3 relative density before and after densification are given on Figure 2.5.4-43.
The densit'ication program required that the mean relative density at each boring location be not less than 75 percent r_
for the sands and gravels as determined by the Gibbs and Holtz (1957) one sample within relationships. In any one boring, not more than
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the sands and gravels was allowed a relative density less than 70 percent and none were allowed to be less than 65 percent.
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The results of the after-densification borings are summarized on r
Figure 2.5.4-43.
Only three of 93 sand and gravel samples have relative densities lesa than 65 percent, and of these, two are very close to the soil surface.
- Thus, it is concluded that adequate densificat:.on of the sands and gravels was achieved with a mean relative density of 92.3 percent and a mean-less-one-standard-deviation rela'tive density of 79.8 percent.
Surface and Subsurface Instrumentation o y 2.5.4.13 RF Ine,-t A was established in mid-1977 to monitor ths comprehensive program
@ 2..G",4-Joa). aettlement of the BVPS-2 structures during and aften construction.
g bench marks were installed at various locations around the
.TMert 8.[ Permanent site to provide reliable survey reference points.
Several
('
, g,,y,4 31 piezometers were installed to monitor changes in ground-water
=-
elevation in order to evaluate possible correlations between 4 N' settlement data and changes in ground-water elevation. In each S
3-structure a series of settlement markers were or-will be installed
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during construction. They are so located that they can be monitored throughout the construction pnase as.well. as after construction. The locations of the bench marks and pie:ometers are shown on Figure 2.5.4-14 and the locations of the settlement markers installed ee at present are shown on Figures 2.5.4-44 and 2.5.4-45.
g The observed settlements to date (Figure 2.5.4-46) can be compared 1
E with the predicted total stTtic se ttlements as shown on Figure 2.5.4-20.
2.5.4.13.1 Bench Marks y(
Six permanent bench marks were installed at the locations shown on Y
Figure 2.5.4-14.
A typical bench mark installation detail is shown I
on Figure 2.5.4-47.
It consists of a 2-inch diameter extra strong steel pipe anchored into bedrock, inside of a 3 1/2-inch diameter 5
E casing extending to the top of rock. The bench, marks are identified by a brass monument inscribed with the bench mark number, elevation,
.y coordinates, and date of initial survey.
a The elevations of the bench marks were checked at three-month i
intervals for the first year after installation and once per year r.
thereafter.
In addition, the elevations of bench marks in the
-W i
Amendment 4 2.5.4-30 December 1983 W
==
=
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f-
' INSERT "A" The ' settlements. of all - BVPS-2 Category I structures are being inonitored
' during construction and will be monitored throughout the life of the plant.
A comprehensive program was es tablished in mid-1977 to monitor the settle-
'ments during construction and to aid in establishing the long-term, pos t-l' construction settlement nonitoring program.
2.5.4-30a i
+-
BVPS-2 FSAR immediate vicinity of construction activities are monitored monthly q
and any bench mark that is disturbed or is suspected of being disturbed is resurveyed.
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Bench marks are checked by running one or a series of leveling loops
,within the established bench marks.
If, by comparison with the elevation measured during the original survey, it has been determined that a bench mark has been disturbed, a new brass monument is installed and the bench mark resur'teyed.
All survey work performed in conjunction with checking and reestablishing bench marks is done using first order vertical control.
2.5.4.13.2 Piezometers six stand pipe piezemeters were installed at the locatiens shown on are shown Figure 2.5.4-14.
Typical piezameter installation details on Figure 2.5.4-27 and specific installation data are given in Appendix 2.5A.
Tip elevations range between el 646 and el 651 feet and all of the piezometers are located within the in situ sand and gravel.
Piezometer data and Ohio River elevation data are recorded weekly and are included in Appendix 2.5A.
With the exception of one period during February 1979, the ground-water levels recorded in the piezometers show very good correlation with the Ohio River O
elevations.
During February 1979, the river rose to el 6EL feet and the piezometer data indicate an apparent time lag.
- However, the piezometers were only read weekly during the period of high water and in the interim between readings the water level in the piezometers may have-continued to rise, thereby reducing the apparent elevation difference between the ground-water levels and the Ohio River elevation.
2.5.4.13.3 Settlement Markers The locations of the currently installed settlement markers are shown
.l on Figures 2.5.4-44 and 2.5.4-45.
Details of the several types of markers are shown on Figure 2.5.4-48.
Construction activity in certain structures requires that settlement markers be relocated periodically in order to provide continuing access to the markers.
In such structur.s, temporary markers have been installed instead of permanent markers. Temperary settlement markers have been installed on the reactor containment building, the safeguards area, the fuel and-decontamination
- building, and the cooling tower.
When construction activity diminishes to the point that markers are no longer subject to periodic relocation, the temporary settlement markers are replaced with permanent ones.
Art bem.p uring construction, settlement markers munitored monthly.
When the individual structures are fully loaded and their settlement u
Amendment 4 2.5.4-31 December 1983 Iment 'B" (we. h 4, 1.s. +-so)
_m
=
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==--
= - - - - - - - - - - - - - -
= - - -
=
/-Ine,fB*(c-dd BVPS-2 FSAR
( 6 -e /. g. 2.s.5-so) profiles begin to level out, the period between readings will be c.,,j increased.
Leveling loops run for settlement monitoring must close to one of the permanent bench marks with a maximum error of 10.005 foot.
2.5.4.13.4 Data Processing Data processing is accomplished using a SWEC computeri:ed data storage system entitled Settlement Monitoring System (IS-233).
The settlement marker elevations are input into the computer storage I
files and a computer printout providing the complete settlement j
record of each marker is produced. A specimen page of output is l
given on Figure 2.5.4-49.
For each settlement marker, settle' ment versus time plots have been prepared using arithmetic and log time scales. These plots are not included herein but are provided in the report on Settlement Monitoring Program (DLC 1980). A summary of the observed settlements to date is provideo on Figure 2.5.4-46.
The Ohio River elevation and pie:: meter data is included in Appendix 2.5A.
2.5.4.14 Construction Notes The removal of uncontrolled fill placed during the construction of
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SAPS and BVPS-1.is discussed irr Section 2.5.4.5.
The removal of a lens of stiff silty clay found during the reactor containment excavation is also discussed in section 2.5.4.5.
of loose granular material was discovered in the SVPS-2 area A sone during the excavation for the reactor containment excavation. It was densified using the pressure injected footing technique.
The densification program and its evaluation are fully described in the Report on Soil Densification Procram, (DLC 1976).
2.5.4.15 References (or Section 2.5. *,
- Bowles, J.
E.
1977.
Foundation Analysis and Design. McGraw-Hill Book Company, New York, N.Y.
- Bullen, K.
E.
1963.
An Introduction to the Theory of Seismology.
Cambridge University Press, Cambridge, England.
Christian, J. T. 1976. Relative Motion Between Two Points During an
- Earthquake. Journal of the Geotechnical Engineering Division, Vol.
102, No. GTil. November, ASCE.
Dravo Corporation 1974. Subsurface Investigation Routing of Sludge Transportation Pipes Around Beaver Valley Power Station, Little Blue
.)
Amendment 4 2.5.4-32 December 1983 1
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