IR 05000498/1982005
| ML20053C335 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 05/07/1982 |
| From: | Crossman W, Hunnicutt D, Tapia J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | |
| Shared Package | |
| ML20053C333 | List: |
| References | |
| 50-498-82-05, 50-498-82-5, 50-499-82-05, 50-499-82-5, NUDOCS 8206010693 | |
| Download: ML20053C335 (4) | |
Text
+
.
l APPENDIX U. S. NUCLEAR REGULATORY COMMISSION
REGION IV
Report:
50-498/82-05 50-499/82-05
'
Dockets:
50-498 Category A2 50-499 Licensee:
Houston Lighting and Power Company (HL&P)
P. O. Box 1700 Houston, Texas 77001
'
Facility:
South Texas Project, Units 1 and 2
'
Inspection at:
South Texas Project and Brown & Root Company (B&R)
,
Office, Houston, Texas Inspection conducted: March 30 - April 2, 1982 Inspector:
. -#6 6-7-62.
. Tapia, g ctor Inspector, Engineering Section Date Accompanying NRC Personnel: D. Sells, Project Manager, Licensing Branch No. 3, Division of Licensing, NRR L. Heller, Section Chief, Hydrologic and Geotechnical Engineering Branch, Division of Engineering, NRR D. Gupta, Geotechnical Engineer, Hydrologic and Geotechnical Engineering Branch, Division of Engineering, NRR 5///[gk Reviewed:
w,---
W. A. Crossman, Chief, Reactor Project Section B Date'
Approved:
h2 umn.m-ff-8/7[8A D. M. H~unriicutt, Chief', Engineering Section Dr ter a
.,
L 8206010G %
-.
.
. _,
-
.
-2-Inspection Summary Inspection on March 30 - April 2, 1982 (Report 50-498/82-05; 50-499/82-05)
Areas Inspected:
Special, announced inspection to review data and analysis dealing with liquefaction potential of identified engineered backfill areas and to review results of geotechnical monitoring.
The inspection involved 28 inspector-hours by one NRC inspector.
Results:
No violations or deviations were identifie.
-3-DETAILS 1.
Persons Contacted Principal Licensee Employees M. E. Powell, Licensing Team Leader R. L. Engen, Civil Engineer M. A. McBurnett, Licensing Engineer G. W. Steinmann, Site Civil Engineer Other Personnel C. B. Pettersson, Lead Geotechnical Engineer, B&R R. J. Woodward, Geotechnical Engineer, Woodward-Clyde Consultants C. Hedges, Project Manager, Woodward-Clyde Consultants M. S. Power, Geotechnical Engineer, Woodward-Clyde Consultants J. M. Young, Civil / Structural Engineer, Bechtel Power Corporation R. H. Talmage, Senior Geologist, Bechtel Power Corporation S. M. Feroz, Soil Engineering Supervisor, Bechtel Power Corporation 2.
Liquefaction Analysis The NRC inspector accompanied two geotechnical engineers from the NRC Office of Nuclear Reactor Regulation (NRR) in reviewing the data and analysis dealing with the liquefaction potential of identified engineered backfill areas.
The review included the results of the field investiga-tion boring program which identified the four small, isolated zones where a relative density less than construction quality control criteria was indicated.
Evaluation of the liquefaction potential of the identified zones was accomplished by correlating the stresses developed in a zone with the standard penetration resistance values.
Using this technique, the licensee, in its " Final Report Concerning Show Cause Order Item 2,"
reported a factor of safety against liquefaction of greater than 1.5 for three zones and a minimum factor of safety of 1.35 for the fourth.
The calculations, Document No. Y310XC004 ASH, of those reported factors of safety were reviewed during this inspection.
The document included calculations performed by Dr. H. Bolton Seed and verification calcula-tions performed by Shannon & Wilson, Inc., Geotechnical Consultants.
A similar calculation, Document No. Y310XC005 ASH, for the analysis of thin layers immediately below mat foundations at a relative density of 45 percent, was also reviewed.
The reported factor of safety against liquefaction for this 4-inch layer was 1.8.
As reported in NRC Inspection Report No. 50-498/81-10; 50-499/81-10, paragraph 4, this review by the Geotechnical Branch of NRR is being per-formed at the request of the NRC's Office of Inspection and Enforcement.
.
The licensee's conclusions relative to the calculations addressing the
!
liquefaction potential are being evaluated, and the NRR reviewers will document their findings in the Safety Evaluation Report.
l l
l
'
_
_
__ _ ___
_
_
.. _
.
._ _
i
-
.
.
l
.
-4-
!
!
3.
Geotechnical Monitoring The NRC inspector reviewed the following calculations:
No. 3Y310SC264-14F,
" Differential Settlements in Unit 1 Buildings," and No. 3Y3105C264-18C,
" Differential Settlements in Unit 2 Buildings." These documents present
!
'
comparisons of structural movements at instrumentation locations along sections in each. building.
The reviewed calculations represented data which had been reduced as of June 15, 1981.
The licensee is in the process of updating the settlement results and committed to submit the information
.
when available.
Geotechnical instruments used are Borehole Heave Points and Sonde Extensometers.
The field measurement of geotechnical instru-ments and structural benchmarks is performed in accordance with Technical Reference Document No. SY310SR112-B, "Geotechnical Monitoring." The NRC representatives toured the site and observed the location and condition
"
of instruments and benchmarks.
,
Geotechnical monitoring activities will receive continuing assessment in the course of subsequent inspections.
s i
No violations or deviations were identified.
.
?
l i
i
,
i
,
,
. -. -. -. _ -
... - -. -
7,
-.,.. -
,
,
_.
.., -..
,.-.,.-.-
-
-
-