ML19221A972
| ML19221A972 | |
| Person / Time | |
|---|---|
| Issue date: | 03/31/1979 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| NUREG-75-087-02.5.1, NUREG-75-087-R-790331, NUREG-75-87-2.5.1, NUREG-75-87-R-790331, SRP-02.05.01, SRP-2.05.01, NUDOCS 7907120093 | |
| Download: ML19221A972 (5) | |
Text
$pt e "f G oq' NUREG 75/087 o
!\\-
/,;,
U.S. NUCLEAR REGULATORY COMMISSION
< f1,4 W5pl STANDARD REVIEW PLAN
\\..# M OFFICE OF NUCLEAR REACTOR REGULATION SECTION 2.5.1 BASIC GE0 LOGIC AND $EISMIC INFORMATION REVIEW RESPONSIBILITIES Primary - Geosciences Branch (GB) g Secondary - None I.
AREAS OF REVIEW GB reviews the geologic and seismic irformation submitted in the applicant's safety l
analysis report (SAR) in accordance with Appendix A to 10 CFR Part 100, " Seismic and Geologic Siting Criteria for Nuclear Po er Plants." GB judges the adequacy of the l
geologic and seismic information cited in support of the applicant's conclusions con-cerning the suitability of the plant site. The geologic and seismic information which must be provided in order for the site review to proceed is divided into the following three categories; l.
Gco'ugic Satures: mass-wasting, differential subsidence, faulting, soil and foundation instability, chemical weathering, cavernous or karst terrains, evidence of preconsolidation via erosional processes and volcanism.
2.
Seismic features: ground failure under cynamic loading, liquefaction, 'fibratorv ground motion, tsunami, and residual stresses.
l 3.
Man-made conditions: changes in groundwater conditions, s bsidence or collapse caused by withdrawal of fluids or mineral extraction, induced seismicity and fault movement caused by fluid injecticn or withdrawal.
Information relating to the above corditions as presented in SM Sections 2.5.1.1 (Regional Geology) and 2.5.1.2 (Site Geology), should be reviewed in terms of the regional and site physicgraphy, geomorpholcgy, stratigraphy, lithology, and tectonics.
In addition, with specific reference to site geolcgy, the following subjects should be reviewed as they relate to the above-mentioned conditions: topography, slope stability, l fluid injection er withdrawal, minerml extraction, faulting, shearing, jointing, seismicity and fracturing.
l The above information should be documented by appropriate references to all relevant published and unpublished materials. Illustration should include but should not be USNRC STANDARD REVIEW PLAN siendero re.,ew piens..e p.epe,ed for the gu.dence of the off.co of Nucies, Reac to, Reguisi,on et off <espor.s bie so, ihe,e..e of oppuoi.ons to construc,.nd operate nucleetpowee plants These documents see made eve:iebie to ttie pubase se peat of the Commission o pow y to mform the nurteer.ndustry and the gene +ei pubhc of regu.etory procedures and pohr en Standard eeview piens are not subst+tu *e for requietory guides oe the Commiss.on s rogu stmas and e
compoence w.th them to not requared The stande,d reviour pteri secteens e e hoved to Revis on 2 of the Stende<d Format and Convent of Sa'ett Analys s Reports for Nuc ees Powee Plante swot all se(ttons of the Stenderd Poe, net have a correspondmg review pian Pabhseed standard review piens weit be rev+ned period +ceity se appropriate to secommodete comments and to retinct new mformation and esperience Commente end suggest ons for enprovement will be cons de<ed and should be sent to the U S Nuciens Reguietory Commieseon Office of Nucteer Reactor Regu setten Wreshmeten D C 20566 79071200 0 6 008 a'
limited to physiographic, topographic, geologic, tectonic, gravity, and magnetic maps, structure and stratigraphic sections, buring logs, and aerial photographs. Certain sites wil! require illustrations of specialized character such as maps of subsidence, irregular weathering conditions, landslide potential, hydrocarbon extraction (oil or gas wells), faults, joints, and karst features. Some site characteristics must be l
documented by reference to seismic reflection or refraction profiles or to maps pro-duced by various remote sensing techniques.
As appropriate, maps should include a superimposed plot plan of the plant facilities.
Other documentation should show the relationship of all seismic Category I facilities (clearly identified) to subsurface geology. Core boring logs, logs and maps of trenches, aerial and Environmental Resources Technology Satellite (ERTS) photographs, and geo-physical data should be presented for evaluation. In addition, a plot plan showing the locations of all structures, borings, trenches, profiles, etc. should be included.
The review can be brought to an earlier conclusion if the following suggestions are followed by the applicant. The SAR should contain sufficient data to allow the reviewer to make an independent assessment of the applicant's conclusions. That is, the reviewer shcild be led in a logical manner from the data and premises given to the conclusions that are drawn without hav ng to make an extensive independent literature search.
i Controversial information should not be ignored so as to enhance a particular position.
The geologic terminology used should conform to standard reference works (Refs. 3, 6).
Finally, the objective of Section 2.5 of the SAR is to describe geologic anj seismic features as they affect the site under review, and all data, information, discussions, interpretations, and conclusions should be directed to this objective. Aimless presen-tation of data, although it may appear to satisfy the investigative requirements, will result in a disjointed SAR and cause needless delays in completing the safety review.
II.
ACCEPTANrE CRITERIA The " Seismic and Geologic Criteria for Nuclear Power Plan +s" (Ref. 1) and the Standard Format (Ref. 2) are the basis for the staff review of all tases. The information presented in the SAR must be complete and thoroughly documented, and must be consistent witn the requirements of References 1 and 2.
United States Geological Survey (USGS) and other Federal or State agency published and open file papers, maps, aerial photo-graphs, geophysical data, etc., covering the region in which the site is located, are used to establish the staff's conclusions as to the completeness and acceptability of the SAR.
Subsection 2.5.1.1, " Regional Geology," will be considered acceptable if a complete and documented discussion is presented of all geologic, seismic, and man-made features.
This section should contain a review of the regional physiography, geomorphology, stratigraphy, structure, and geologic history to provide a framework within which the geologic, seismic and man-made features of '. fety significance to the site can be evaluated.
Rev. 1 2.5.1-2 146 009
Subsection 2.5.1.2, " Site Geology," will be judged acceptable if it contains a descrip-tion and evaluation of site-related geologic features, seismic conditions, and man-made conditions which are a potential hazard to the site. This section should also contain 9
the following general site information:
1.
The site stratigraphy, including relationship to and correlation with the regional stratigraphy.
2.
The structural geo'egy of the site and the relationship of site structure to regional tectonics.
3.
The geologic history of the site as it relates to the regional geologic history.
4.
The engineering significance of geologic features underlying the site as they relate to:
a Dynamic behavior during prior earthquakes.
b.
Zones of alteration, irregular weathering, or zones of structural weakness.
c.
Unrelieved residual stresses in bedrock, d.
Materials that could be unstable because of their mineralogy or unstable physical properties.
e.
Effects of man's activities in the area.
5.
The site groundwater conditions.
III. REVIEW PROCEDU E The staff review is conducted in three phases. The first phase is the acceptance review, a brief review of the SAR to evaluate its completeness and to identify obvions safe *y issues that could re ult in delays at subsequent stages of the review. After an san is docketed, the staff condt. cts a thorough review of the material. In this second pnase of the review an effort is made to identify all safety issues. The reviewer should carefully examine the SAR to see that all interpretations are founded on sound geological and seismological practice and do not exceed the limits of validity of the applicant's data or of other data published in the literature. The questions and coments transmitted to the applicant will identify issues that have not been addressed, areas where staff interpretations differ from those given in the SAR, and issues that have not been sufficiently documented to permit the staff to concur in the conclusions reached by the applicant. When possible, tne staff should take positions on safety-related issues at this point. The third review phase is the staff evaluation of the applicant's responses to questions raised in the second phase. At the end of the third phase, the staff takes positions on all safety-related issues, either concurring with 2.5.1-3 Rev. 1
the applicant's positions or taking ir conservative positions as may be necessary in the staff's view to assure the required degree of safety.
Pertinent references, such as published geological reports, professional papers, open file material, university theses, physiograph'c and geological maps, and aeromagnetic and gravity maps, are ordered from the appropr, ate sources and reviewed. The general references used extensively by the staff are References 3 and 4.
The GE0-Reference File (Ref. 5) is used to identify specific references.
The judgments on acceptance or rejection of the SAR are governed by two criteria: (1) adherence to the Standard Format in identifying and describing the geolo6ic, seismic and man-made features that affect safety of the site; and (2) provision of adequate information and documentation to allow for an independent review of the conclusi3ris made therein.
During the acceptance review the staff decides to what extent consultants such as the USGS, the Corps of Engineers, State geological survey organizations, or other specialists should be involved. The nece ary information is then made available to these consult-ants. Consultants are asked to nandle such varied tasks as reviewing the geotechnical l
engineering aspects of plants located at sites with complex foundation conditions, verifying an applicant's mineral identifications, or evaluating the suitability of foundations with respect to bearing capacity and settlement and evaluation of sicpe stability conditions for safety-related slopes, dams and dikes.
9 Af ter ducketing, a detailed review of the SAR and relevant refere nces is conducted by the staff and its advisors. Questions and comments are developed from items that have not been adequately addressed by the applicant, those which becomi apparent during the detailed review, or those which develop from the additional information provided as a result of the acceptance review. These questions (Q-1) usually rec,uire the applicant to conduct additional investigations cr to supply clarifying information. Many ques-tions result from the reviewer's discovery of references not cited by the applicant that contain conclusions which are in conflict with those made by the applicant. When the applica.t provides insufficient data to support his interpretations and conclusions, and there are reasonable and more conservative alternative interpretations in the l
literature, the staff will request additional investigations. This phase of the review will usually involve meetings with the applicant to clarify questions and allow him to present new data.
In addition, during the Q-1 phase, the staff visits the site.
The applicant's responses to Q-1 are reviewed and any remaining issues are settled either by additional questions or by staff positions. A staff position is usually in the form of a requirement to design for a specific condition in a way which the staff cons. M tu be sufficiently conservative and consistent with the requisites of l
Reference 1.
When all safety issues have been resolved, the staff provides its input to the safety evaluation report (SER).
Rev. I 2.5.1-4
IV.
EVALUATION FINDINGS The staff's findings for construction permit (CP) reviews will consist of a report summarizing the geology at the site and the pertinent design aspects of the plant. All geologic features that may potentially aff N t the safety of the plant will be identi-fied, described, and measures taken to deal with them will be given. The seismic design b': sis will be described.
Operating license (OL) applications are reviewea for any new information developed subsecuent to the CP.
The review will also determine whether the CP recoromendations have '.;een implemented.
A typical CP-stage finding for this section of the SER follows:
"Ba,ed on our review of the PSAR materials and our independent review of the relevant published literature, we have concluded that the site is located in the Piedmont tectonic province. The last recognizable regional tectonic event occurred here in Triassic to Jurassic time (225 - 136 mybp). No Holocene faulting of tectonic origin is known in the province and no capable faults within the meaning of Appendix A to 10 CFR Part 100 have been recognized."
V.
REFERENCES 1.
10 CFR Part 100, Appendix A, " Seismic and Geologic Siting Criteria for Nuclear Power Plants."
2.
Regulatory Guide 1.70, " Standard Fermat and Content of Safety Analysis Reports for Nuclear Power Plants," Revision 2.
3.
M. Gray, R. McAfee, Jr., and C.
L. Wolf, eds., " Glossary of Geology," American Geological Institute, Washington (1972).
4 G. V. Cohee (chairman) et al., " Tectonic Map of the United States," U. S. Geo'ogical Survey and American Assnciation of Petroleum Geologists (1952).
5.
"Geo-
Reference:
Computerized File of Earth Science Titles," American Geological Institute, Washington.
6.
M. W Higgins, " Cataclastic Rocks," Professional Paper 687, U. S. Geological Survey (1971). (Includes extensive discussion of the terminology of cataclastic rocks.)
146 012 2.5.1-5 Rev. I