ML20128C120
| ML20128C120 | |
| Person / Time | |
|---|---|
| Site: | Vogtle, 05000426, 05000000, 05000427 |
| Issue date: | 05/31/1973 |
| From: | Morris R INTERIOR, DEPT. OF, GEOLOGICAL SURVEY |
| To: | |
| Shared Package | |
| ML19292B772 | List:
|
| References | |
| FOIA-84-624 NUDOCS 8505280191 | |
| Download: ML20128C120 (52) | |
Text
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e DRAFT REMorris 5/21/73 Site Examination report, Alvin T. Vogtle Inclear Plant Units 1, 2, 3, h Docket Nos. 50 k24, h25, h26, h27 The site visit to the Alvin T. Vogtle Nuclear Plant (VNP) was conducted April 2h and 25, 1973. In attendance vere representatives from the applicant, Georgia Power Co., and consuJting fir =s Southern Services, Inc., and Bechtel Corp., and me=bers of the AEC staff and U.S.G.S.
The VNP is located on the southwest tank of the Savannah River, near Augusta, Georgia. The AEC Savanrah River Plant is directly across the river in South Carolina. All major facilities of VNP vill be on the crest of a broad well-drained hill. Surface soils are sandy and are derived frem weathering of typical coastal plain sediments. Within the near surface strata are calcareous fossil zones that in some instances have been dissolved by ground water and collapse sinks have formed over the voided zene. The applicant plans to remove these critical strata in the are. of Class I structures. The excavation vill require removal of about 100 feet of ' strata in order to reach a suitable founding stratum, described in the PSAR as the bearing stratum, which is a clayey silty marl.
The marl has very low permeability and for=s an aquaclude between ground
~ water of the overlying and underlying strata. The clay / marl ranges in g528 1 g41015 SHOLLys4-624 paa
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thickness from 60 to 100 feet. Two velocity layers are recognized in the unit, a lower zone with a sonic velocity of near 7,000 fps (compressional wave) and an upper zone of about 5,000 fps. Outcrops of the unit were observed 'in bluffs along the Savannah River.
Core samples from several test holes, selected from over 300 holes drilled during site subsurface investigations, were displayed for examination. Structure contours of the bearing strata show a southwesterly-plunging asymmetric anticline with very shallow dips to the southeast and slightly steeper dips to the northwest. There are no indications of faults within the area for which structure contours are shown. The VNP site appears to be favorably located with regard to structural setting, although.there may be some nearby Triassic basin-bounding faults buried by the 1,000 or more feet of coastal plain strata in this area.
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'/h flSGLC AEC Question 2.19 4
What is the geologic significance of the clastic dikes mentioned on page 2.5-6?
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Response
I Refer to paragraph 2.5.1.3.2.
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VNP AEC Question 2.20 i
On pages 2.5-2,3 the basement complex is describ'ed as also including Triassic sediments.'+'What is the configuration and location, with respect to the site of the Triassic basin? What is the evidence that the basin is not bounded by faults, in a manner similar to other fault-bounded Triassic basins in the Piedmont.
Response
Refor to paragraph 2.5.1.3.1..
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'AEC Question 2.21
-t The cross _section (B-B'). illustrated in figure 2.5-6 shows a monoclinal' flexure (albeit with' vertical exaggeration).. Discuss the structural.
relationship of this flexure and any bounding fault of the Triassic basin.
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Response
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e-2.21 7/6/73 Amendment 3-
WP AEC Question 2.22 T
Discuss.the possible relationship between the apparently anamalous high seismic response in.the zone. enclosed by the 8-1/2 value shown on fig-
.ure:2.5-26 to basin bounding structures in the basement complex.
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Response
Refer to paragraph 2.5.2.10.
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l 7/6/73 Amendment-3 2.22
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V5P AEC Question 3.3 f
The s'implified lumped mass and soil spring approach proposed in the PSAR to characterize soil-structure interaction is not appropriate. The use of equivalent soil' springs may produce a pronounced filtering of the ground motion response amplitude and response frequencies due to inadequate repre-sentation of soil parameters.
Indicate ycur intent to adopt one of the following methods for soil-structure interaction analysis:
(a) A nonlinear finite element approach with appropriate nonlinear stress-strain and damping relationship for the soil.
3 (b) An iterative linear finite element approach with appropriate nonlinear stress-strain and damping relationship. for the soil (pseudo-nonlinear approach).
(c) Lumped springs to represent the soil with appropriate dampings (not more than 10% of critical damping corresponding to horizontal and vertical springs), utilizing a variation in the soil properties corresponding to the span of maximum and minimum strain levels so that the floor response spectra obtained envelop those using the finite element approach.
If a pseudo-nonlinear finite element approach is used, identify the manner in which variation in the properties of the soil are accounted for.
(Para. 3.7.2.1)
Response
3 See paragraph 3.7.2.1.1.1.
3.3 7/6/73 Amendment 3
.. s' gp AEC Question 3.4 Specify the' number of significant cycles of stress reversal expected during the lifetime of the plant. Describe how this number is arrived at by pro-viding information on the estimated number of seismic events, and the magni-
-3 tude duration and number of stress cycles for each event.
(Para. 3.7.3.1)
Response
Refer to paragraph 3.7.3.1.1.
7/6/73 Amendment 3 3.4
VNP
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Cretaceous period.
Seismic refraction surveys at the site indicate that this basement complex-Cretaceous contact occurs at a depth of approximately 950 feet.
More or less constant 4
deposition continued from the Cretaceous through mid-Tertiary f
periods in the Savannah River basin area with the youngest identified Tertiary sediments being Miocene in age.
Variegated clays and sands lithologically similar to the Miocene Hawthorne l
formation were encountered in the upper portion of one of the l
higher holes drilled at the site,.but insufficient exposures of 1
these clays and sands were present to show as a mappable unit.
t For regional geology map see figure 2.5-3.
Figure 2.5-4, which is a portion of the Tectonic Map of North America, shows the relationship of the site, on the essentially undisturbed sediments of the Coastal Plain, to the Piedmont Province to the north and' west with its older and more complex geologic units.
The b:sement complex, as exposed in the Piedmont Province, has undergone at least two periods of granitic intrusion or granitization as well as well-developed faulting and folding.
This activity, however, has been i
essentially quiescent since the deposition of the Cretaceous sediments in. tha cos.stal plain.
This wedge of Cretaceous and younger sediments, which feather out at the Fall Line near Augusta, is reported to reach depths of approximately 4,000
(
feet at the coastal line near Savannah, Georgia.
The lowest member of the sediments appears to represent an alluvial deposit, po'ssibly of coalescing fans derived from the erosion of the older basement rocks to the west and north.
The encroaclunent of a shallow sea in the Uppermost Cretaceous and j
Lower Tertiary times resulted in the shoreward migration of estuarine and shallow marine deposits.
In the vicinity of the site, lignitic sands and clays are replaced by marls, coquinas, and shallow water sand.
These deposits grade coastward into deeper water lithological units of the same age, such as limestone and shales.
The present dip seaward of these units is approximately 30 feet per mile at the Cretaceous basement complex contact.
The basement complex is described above as including Triassic l
sediments.
The location and configuration of these sediments l
with regard to the VNP is shown on figure 2.5-4A.
This Triassic basin, its location, and supporting evidence are discussed 'in reference 2. 5.7.2 (Siple, G. E., 1967).
Here Siple discusses the core obtained in the bottom of the holes 3
drilled on the SRP as lithologically characteristic of "the fanglomerate or conglomerate facies of the Newark group of late Triassic age."
The outline of the basin has been determined largely on the -basis of aeromagnetic surveys which show the
- Triassic sediments as " lows" compared to the surrounding igneous-metamorphic Piedmont complex.
2.5-3 7/6/73 Amendment 3 i
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Based.,on what are believed to be similar Triassic basin occur-rences' in the Piedmont area and on the steep magnetic gradient delineating the northwest and southeast edges of the basin, it is assumed that at least these sides are bounded by faults and 3
that,the Triassic sediments have been preserved in a down-dropped graben w$ thin the basement rock.
2.5.1.3.2 Stratigraphy The stratigraphy applicabid to the Savannah River basin area is suussarized in table 2.5-1.
Igneous and estamorphic rocks varying in age from Precambrian to Paleozoic form the lowest unit believed to be present at the site.
This taaterial was not encountered during drilling or indicated by the deep refraction seismic work, but is known to form the true basement material by direct or inferred means throughout the Georgia-South Carolina area.
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2.5-3a 7/6/73 Amendment 3
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VNP Table 2.5-1 STRATIGRAPHIC UNITS IN THE VICINITY OF THE ALVIN W. V0GTLE NtiCLEAR PLANT SITE
- System Series Formation Description Recent Alluvial fill and terrace deposits in Quaternary to Alluvium stream valleys, consisting of tan to Pleistocene gray sand, clay, silt, and gravel.
Miocene Hawthorn Tan, red, and purple sandy clay, Formation interbedded lenses of gravel, and numerous elastic dikes.
i Red, brown, yellow, and buff fine to
,g, Barnwell coarse, massive to cross-bedded sand Tertiary g g)
Formation
'and sandy clay.
4 Eocene Yellow-brown to green, fine to coarse glauconitic quartz sand, interbedded oh, McBean with green, red, yellow, and tan clay, dlg)
Formation sandy unr1 er limestone, and lenses j!
of siliceous limestone.
o Dark-gray to black sandy lignitic Believed Ellenton micaceous clay containing dissemi-to be Upper Formation nated crystals of gypsum. Medium Cretaceous to' dark-gray coarse sand and white kaolin.
Tan, buff, red,. and white cross-bedded Tuscaloosa micaceous quartzite and arkosic sand Cretaceous Upper Formation and gravel, interbedded with red, brown, and purple clay and white kao-lin.
Gray, dark-brown and brick-red sand.
Newark stone, siltstone, graywacke and clay-Triassic Upper Group stone with included sections of fan-glomerate or conglomerate.
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Basement Rock Granite, gneiss, chlorite-hornblen'de, Paleozoic of the and chlorite-tremolite schist, slate, and Carolina Siste and volcanic rocks.
Precambrian Belt and Charlotte Belt
- Af ter Siple in USGS Water Supply Paper 1841 2.5-4
VGD Deposition of continental sediments during the Triassic is known to nave occurred fron samples obtained from drilling N
through the coastal province.
Much of this material was croded during the post-Triassic, pro-cretaceous tine, but local basins containing Triassic sediments woro preserved beneath the peneplain surface formed.
Aerial magnetic surveys in the past decade have disclosed that one of these Triassic basins extends
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fron bcncath the Atomic Encrgy Connission's Savannah River Project (S RP ) in South Carolina to several miles beyond the site of the Vogtlc Nuclear Plant in Georcia.
On the SRP, the basin was confirmed by seismic reflection studies and deep core holes.
The deposits consist of siltstono, claystones, and sandstones resembling those of the typical Newark Group l
fanglomerates of the Upper Triassic period.
Measurements made at the Vogtle site indicate that a material with refraction velocity of 12,000 feet per second exists at approximately 950 feet below the plant site, which agrees with the Triassic basin sediment data.
Overlying the peneplained surface of the Precambrian,-Triassic basement complex is the nonmarine Tuscaloosa Formation.
This foruation is composed larcely of detritus derived from the weatheret granitic-netamorphic basement rocks and contains considerable coarse grained quartz, partially altered feldspar, and mica (generally of the muscovite variety).
In gross ap-pearanco, it consists of light-gray to light-brown to white, g
cross-bedded, arkosic to quartzitic sands and gravels inter-t bouded with lenses of silt and clay, of red, white, brown, or purple color.
Tne variegated clays are generally of'relatively pure kaolin and are nined extensively in the vicinity of the Fall Line.
Overlying the Lower Cretaceous TuscaloosC Formation is the Ellenton Formation, which occurs sporadically and locally within the Savannah River basin, but occurs consistently in the plant site area.
Originally described by Siple in his work on the SRP, it is believed to be of Upper Cretaceous age.
The Ellenton Formation consists of dark-gray to black, sandy, lignitic, micaccous clay interbedded with medium to coarse-grained quartz sand in its type area.
The lower part of the Ellenton Formation is composed generally of a clayey quartz sand varying in texture from medium to coarse-grained, becoming locally gravelly.
Deconposed pyrite or marcasite fragments, lignite, muscovite, and kaolinitic aggregates are quite common.
The Ellenton Fornation is distincuished from the Tuscaloosa Fornation by the latter's marked preponderence of muscovite and kaolin as compared to that in the Ellenton Formation.
Above the Lllenton Formation are the Tertiary deposits of the Locene through niocene periocs.
The lowest of these is the 2.5-5 4
VNP middle Eocene McBean Formation, which has been described as consisting of glauconitic quartz sands of yellow-brown to green color, interbedded with similar colored sandy marls or limestone.
In the Hancock Landing area on the Georgia side of the Savannah River this formation is prominently represented by a bluff-forming, hard, dark gray-green, sandy marl referred to as the " clay bearing horizon" in this report.
The red-brown to buff-colored fine to coarse grained sands and sandy clay overlying McBean have been classically assigned to the Barnwell Formation of late Eocene age.
Recent Strati-l graphic work on the Eocene-Oligocene boundary by Herrick and Furlow (*3, however, suggests these deposits are actually of Oligocene age and that the Eocene Barnwell Formation may not exist in Georgia.
(The time interval from Eocene through Miocene was one of marine advances and withdrawals in the Coastal Plain province.
As a result of these environmental fluctuations, vertical and horizontal variations in deposits of the same age and within a relatively short distance are common.
The confusion of formational nanes in the literature, which is still being unraveled, has resulted in large part from separate names assigned to different facies of the same formations.)
The Tertiary deposit immediately under the soil horizons of the higher elevations is the Hawthorne Formation of Miocene age.
This deposit generally-consists of variegated, orange through violet, dense sandy clay with mottled or alligator-skin appearance due to color patterns.
Clastic dikes are locally common.
The clastic dikes are considered restricted to the Hawthorne Formation and have not been observed in the vicinity
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of the proposed site.
In the site area the Hawthorne Formation is present as a capping on only the ~ highest ridges.
1 A description of the Hawthorne Formation in the Savannah River Plant area.across the river in South Carolina may be found in USGS W.P.S.
- 1841.
On page 58 (figure 20) of this report, Siple shows a photograph of the clastic dikes exposed in a road cut 5 miles northwest of Dunbarton (approximately 13 miles 3
northeast of the plant site).
With regard to the origin of these dikes Mr. Siple has the following comments:
"The origin of the dikes may be attributed to several factors:
(1) shrinkage resulting from weathering, (2) seismic activity, and (3) relief of compressional stresses by the upward movement of plastic material.
Many similar structural features in consolidated sediments elsewhere are generally explained on the basis of the first hypothesis, and the nonoriented or unalined dikes in this area most probably were formed in this manner.
however, this hypothesis does not appear to be a completely satis f actory explanation for the formation of the alined dikes,
inasmuch as they are apparently confined to the post-Eocene or 7/6/73 Amendment 3 2.5-6
VNP i
at least post-Claiborne sediments.
Although the second possibility, seismic activity, is a likely causative force, it also seems probable that the dike itself was formed both by means of infilling, at an equal pace, of overlying material and
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by the mechanism included in hypothesis 3.
So far as is known, there is no material present now in a stratigraphically higher position in the geologic section and similar in composition to the fracture fill that conceivably might have worked down into the fissure as it was being formed.
There is, however, greenish-gray clay in the Hawthorne Formation at downdip localities that could have been present in this area in the geologic past and would be a likely source for such filling.
There is also similar clay stratigraphically lower in the geologic section - a fact which suggests that possibly some dikes were injected up through the younger Tertiary rocks.
3 Conceivably this injection may have been brought about by the failure of underlying beds to support compressional stresses.
Under such conditions the weight of the overlying material would cause a failure in the substructure brought about by ground water solution of the underlying calcareous beds.
When these beds could no longer suppo' t the overlying formations, r
fractures would develop as the superstructure collapsed, and clastic material below would migrate up into the fractures.
I Some corroborative evidence for such an origin is indicated by the large number of solution sinks in the vicinity of the dikes, as for example, in the northeastern quarter of the Ellenton quadrangle.
Conversely, dike swarms are indigenous to those areas exhibiting other features of solution and collapse."
The Quarternary appears largely represented by the flood plain deposits and valley fill associated with the rivers and larger streams in the area.
2.5.1.3.3 Structure The major structural trend affecting the Georgia-South Carolina region along the southern portion is the pre-Mesozoic Appalachian system.
Tectonic activity had ceased on this i
system before the deposition of the Cretaceous sediments in the Savannah River valley area, as is evidenced by the lack of tectonic folding or documented fault offsets in the. sediments.
Faulting, perhaps of major proportions, appears to have occurred in the basement complex during the pre-Cretaceous, t
however, to account for the down-warped or down-faulted segments of Triassic sediments found preserved within the basement complex throughout much of the Atlantic Coastal Plain.
The coastal plain sediments indicate tne Savannah River basin has remained remarkably stable throughout Upper Fbsozoic and 2.5-6a 7/6/73 Amendment 3
VNP i
to 90 feet (+) in Holes 38 and 156, are stratigraphically part of the Oligocene.
This is true, also, for the shell bearing horizon in Hole 45 on the SRP.
2.5.1.4.3 Structure The geologic structure in this area is best illustrated by figure 2.5-10 showing the contours on the top of the bearing stratum.
Although the surface of this marl bed is believed to be a formational contact, the contours indicate only a minimum amount of differential erosion.
The contours were derived from outcrop and drill hole information and indicate a general dip to the south and east of about 30 feet to the mile throughout the plant site area.
The general dip is interrupted on the northeast by a gentle dip to a maximum slope of five percent (3 degrees) to the northwest, and lowers the reversal of the surface of the bearing stratum approximately 50 feet in that direction.
The dip reversal is seen with a 20 to 1 vertical exaggeration on section B-B' of figure 2.5-6.
The trend of the axis is approximately northeast-southwest.
It is an anomaly that has been the subject of much investigation and discussions.
Numerous holes were drilled to determine its character, and g-water pressure tests were made to determine if it affected the watertightness of the bearing stratum.
No indication that it was a fault controlled feature was found during the extensive inves tigations.
It does not appear to be an erosional feature on the top of the unit as it is reflected in both the top and bottom of the bearing stratum to an approximately equal extent.
It dips in the wrong direction to reflect possible near-surface 3
expression of the underlying Triassic basin boundaries.
No relationship to the assumed boundary fault contact at the northern edge of the Triassic basin could be found.
As the assumed northern Triassic basin boundary fault would have to be down-thrown towards the sea, the fact that the flexure in the bearing horizon slopes in the opposite direction, i.e.,
to the northwest, seems to negate any genetic relationship.
It appears to have been formed previous to and in part possibly during the deposition of the thick shell deposits that roughly coincide with the reversal, as may be seen on figure 2.5-10A.
A local, well developed, striated bedding plane was found in one hole (No. 246) at the base of the marl.
This is near the southwestern or lower side of the anomaly and well away from the plant area.
Water losses were also noted related to jointing in the upper 15 feet of the marl during some exploratory drilling investigating this feature.
These phenomena were not observed elsewhere throughout the plant site investigation.
It is believed that the reversal represents 2.5-11 7/6/73 Amendment 3
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VNP deposition on an erosional irregularity on the underlying sands, with the possibility of some local differential compaction during or shortly after deposition of the bearing stratum.
Solution depressions are readily apparent on the topographic map of the site and, as the site explorations shown on figure 2.5-1 indicate,-they were the subject of considerable i
2.5-lla 7/6/73 Amendment 3 l3
VNP investigation, both from geophysical and drilline and coring techniques.
These depressions were found to be due to the leaching of calcium carbonate from the shell zone, with subsequent settling of the overlying materials.
The underlyine bearina stratum, being a clayey and impermeable aquiclude, acts as a barrier to the downward migration of the shallow ground waters, causing them to discharge as springs alona the upper
. surface of the bearing stratum.
The generally disseminated nature of the shells throughout the shell zone does not lead to the formation of steep-sided sink holes, as would be the case in a true limestone topocraphy.
Although minor solutien channels do exist and were encountered in the drillinn above the bearina stratum, there was no evidence of significant deterioration of the bearing stratum due to solutioning activity.
As the foundation excavation for the plant will remove all materials above the bearing stratum (see figure 2.5-11) solutioning of the overlying shell zone does not pose a geologic hazard for the plant.
2.5.1.4.4 Ground Water Conditions The plant site is on an interfluvial high underlain by permeable sands.
At a depth of less than 80 feet is the marl, or bearing unit, which is impermeable, restrictina vertical movement of ground water.
The marl thus separates unconfined around water in the sands from the underlyina Tuscaloosa aquifer system.
The stream channels boundina the site have cut down to the marl and act as interceptor drains for ground water moving laterally through the sands, preventina inflow or out flow to adjacent areas.
Gr und water present beneath the marl is confined, and is part 2
of the Tuscaloosa aquifer system.
The marl has been determined to be impermeable and there is no movement of water through it.
The field studies and permeability tests to determine the aquifer characteristics are described in subsection 2.4.13, along with a more detailed discussion of ground water conditions.
l The field studies included installation of observation points to nonitor water levels in the two aquifer zones.
Eiahteen l
I points are present in the shallow sands, and fourteen are maintained open to the confined zone beneath the marl aquiclude.
These are listed in table 2.4-2, and water levels taken are summarized in table 2.4-3.
The water table below the plant site is at a depth of 45 feet.
Water table levels for October 1971 are shown on figure 2.4-24.
6/4/73 Amendment 2 2.5-12
VNP I
The map divides the coterminous United States into the following four zones:
Areas where there is thought to be no reasonable expectancy of earthquake damage - Zone 0 I
Areas of expected minor damage - Zone 1 Areas where moderate damage could be expected - Zone 2.
Areas where major destructive earthquakes may occur -
zone 3 7
The site lies inside Zone 2 where moderate damage could be expected.
According to this map, moderate damage corresponds to intensity VII on the Modified Mercalli Scale.
The zones are based principally on the known distribution of damaging earthquakes, their intensities and geological considerations.
Since the Charleston earthquake of August 31, 1886 resulted in the greatest intensities in this part of the country, the zones there will be based on data from this shock.
The Dutton isoseismal map most probably forms the basis for the zones in this area; therefore, since the Dutton map included,
the site in the VII (MM) area, it appears in this zone of the
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risk map even though the site may never have experienced en intensity this high in historic times.
The high seismic response zone enclosed by the 8-1/2 (Rossi-Forel) isoseismal line shown on figure 2.5-26 has been discussed by C. E. Dutton in "The Charleston Earthquake" (USGS 9th Annual Report, 1887-88).
"......The shocks at Columbia, South Carolina, judging from all accounts, were more forcible than 'at Savannah.
The first two impulses, which appear to have corresponded to the two maxima already described at Charleston, threw the whole city into a state of terror.
The swaying of buildings was very great; the jarring, like that of a wagon rumbling over a stony pavement, was excessive, shaking down plaster, chandeliers, crockery and light objects, and producing a loud rattle, which, added to the J
subterranean roaring, caused the greatest consternation.......
Still no instances have been reported of the demolition of any buildings.
The most remarkable circumstance, however, connected with Columbia is the fact that a considerably greater intensity is indicated for that city than for the localities to the southeast of it nearer to the centrum.
There is, indeed, a belt of country along the Piedmont region where the same state 2.5-45 7/6/73 Amendment 3
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VNP
'of' affairs prevailed, and this belt coincides with a marked change in the geologic formations.
It is that belt where the Tertiary-Cretaceous system of marls, sandstones, clays and quicksands forming the great coastal plain and lower Piedmont region terminate and the more ancient metamorphic crystalline rocks appear.
In South Carolina and in adjoining portions of Georci.a and North Carolina the unconformable contact of the older and later rocks is found, stretching from northeast to southwest.
Towards the ocean are the later formations, while to the north-westward lie the older rocks of the Southern Appalachian region.
A line drawn from the earthquake centrum to Columbia would cross the line of contact of the two stratigraphic systems almost perpendicularly.
The earthquake impulses leaving the centrum declined in energy towards the northwest at a rate which seems to be a natural one, so far as can be judged i
from the accounts at hand.
But as they approached the line of l
contact of the younger beds with the older, the energy seems to have increased for a time as the waves sped onward.
Thus at Orangeburgh, which is 32 miles nearer the centrum than Columbia, the account given by Prof.
R.
Means Davis leaves j'
little doubt that the violence of the shocks was notably ~1ess.
Nor was Orangeburgh exceptional in this respect when compared 3
with 'other localities similarly situated with reference to the contact lines of the strata.
Similar accounts indicating a l
more moderate energy come from many other places in the same county; also from Barnwell, Williston, Statesburg, Camden i
Junction, and Sumtar.
But if we proceed northwestward from these places until we reach the older metamorphic rocks - we find traces of increased vigor.
Thus Augusta, in Georgia, just beyond the 100-mile circle, was shaken with great violence.
Many buildings were seriously damaged.........-
So great was the alarm felt, that business and society were for two days as fully paralyzed as in Charleston.
Everyone was in a state of apprehension that the worst was yet to come and the only thing to be thought of was safety.
Indeed, among all the large cities of the South the general tenor of the reports indicates that Augusta stands next to Charleston in respect to the degree of violence of the shocks and the consternation of the people.
Augusta is built in close proximity to the contact of the newer and older strata, and starting from that city it will be of interest to follow this line of contact northeastward.
In detail the course is more or less sinuous........
In this neighborhood the towns of Bath, Graniteville, and Vauclusa, which stand upon outcrops of crystalline rocks, report shocks of very great severity.
Still farther to the northeastward,
'Batesburg, Leesville, and Lexington give similar reports....
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7/6/73 Amendment 3 2.5-45a L
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Throughout the State of North Carolina the vigor of the shocks was very great........
There 1s, however, a notable difference as a general rule between the eastern part of the State within the coastal region and the Piedmont and mountain region.
It was notably less forcible in the coastal plain........
There are"many indications that the vast masses of littoral deposits e
I of unconsolidated sands, clays, and marls along the Atlantic 3
border and coastal plain, especially in the Carolinas, greatly tempered and modified the force of the earthquake.
It may be said that they ' cushioned' the shocks, not elastica 11y, but by actually dissipating in some measure portions of the rays of energy which here affected the surface........"
2.5.2.11 Earthquake Frequency Table 2.5-10 shows earthquake frequency in the vic'nity of the i
Vogtle site.
It is based on actual data from the historic earthquake record of about 300 years, and shows the shocks which were felt in the site area.
2.5.2.12 Sununary and Conclusions I
The first historical quake felt in the eastern Uniter! States is
(
listed as occurring in Canada in 1663, so there is an historical earthquake record of 300 years for the scutheastern i
United States.
This area of the country experiences moderate to low' earthquake activity with the exception of the Charleston area.
The greatest intensity experienced at the site resulted 4
l from the August 31, 1886, Charleston earthquake about 104 miles east of the site.
Considering the reports from nearby towns, the intensity at the site was no greater than a VII.
The great New Madrid, Mo. 1811-1812 shocks were also felt at the site, but with no greater intensity than VI (MM).
Other distant and nearby shocks, however, have been barely felt at the site, probably with no greater intensity than IV.
2.5-45b 7/6/73 Amendment 3 i
l
Table 2.5-10 EARTilOUAKES FELT AT TIIE VOGTLE SITE Miles Latitude Longitude Epicentral From-Probable Intensity.
Date
- N
- w Intensity Site at Site 1811-1812 36.6 89.6 XII 500 No greater than VI 1843, Jan. 4 35.2 90.0 VIII 500
. Barely felt at site l
1861, Aug. 31 Virginia VI 400 Very low at site
.l 1886, Aug 31 32.9 80.0 X
104 VI or low VII l
1886, Oct. 22 32.9 80.0 VI 104 Recorded in Charleston, Atlanta,_ Augusta and i
u Elsewhere i
8 1886, Oct. 22 32.9 80.0 VII 104 Recorded at Summerville, N
w 5
S Washington, Richmond, Louisville, and Elsewhere a
1886, Nov. 5 32.9 80.0 VI 104 Recorded at Charleston, Richmond, Washington, i'
and Elsewhere 1903, Jan. 23 32.1 81.1
'VI 82 III or less i
1905, Jan. 27 34.0 86.0 VII 200 Very low at site i
1907, Apr. 19 32.9 80.0 V
104 III or less 1912, June 12 32.9 80.0 VII 104 IV or less 1914, Sept. 22 33.0 80.3 V
87 III or less 1916, Feb. 21 35.5 82.5 VI 163 IV or less 1916, Oct. 18 33.5 86.2 VII 275 Very low at site I
1945, July 26 34.3 81.4 VI 83 III or less 1959, Aug. 3 33.0 79.5 VI 134 IV or.less 4
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REFERENCE
- ,s '
Geology and Ground Water e
aleckville
'"~ ', '
-dl((
l of the Savannah River Plant
. js j5f[h h f
.i and Vicinity, by GeorgeE.Siple sc ~Mkskma, ggrgc Geological Suryey Water-M _ W@eg~p> M@Mg@jj.ifSF
,l Supply Paper 1841.
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m SCALE IN MILES N
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y 04 %9 TI APEltTUllE b.t.,CAllD ALVIN W. V0GTLE NUCLEAR PLANT Also Avmilable On UNITS 1,2,3 & 4 h
l TRIASSIC BASIN 8f* 5' 30' Tl FIGURE 2.5-4A.
g APEltTUltE 7fsf73 3,,,namone 3 I
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VNP i
Based on what are believed to be similar Thiassic basin occur-rences in the Piedmont area and on the stee'p magnetic gradient delineating the northwest and southeast edges of the basin, it 3
is assumed that at least these sides are bounded by f aults and that the Triassic sediments have been preserved in a down-dropped graben within the basement rock.
The geology and tectonics of South Carolina north'of the Savannah River in the vicinity of the VNP site is very similar in most respects to that in eastern Georgia.
Regional geology of South Carolina in the vicinity of the site is illustrated in the accompanying figure 2.5-3A; some details of structure are-shown on figure 2.5-3.
The five topographic belts of the Coastal Plain as described in paragraph 2.5.1.2 continue across the Savannah River into South Carolina; however, the two innermost or landward belts are 5
narrower and less well defined.
In eastern South Carolina, the Congaree Sand Hills belt is an extension of the Tif ton Upland and-Fall Line Hills belts of Georgia.
In western South Carolina toward the Savannah River, the Aiken Plateau interrupts the trend of the Congaree Sand Hills (Cooke, 1936, figure 1).
It is characterized in its more poorly drained and less dissected parts by shallow undrained depressions
(" Carolina bays") that appear to be caused by the underground removal of calcareous material occurring as limy facies of the Barnwell or McBean formations.
2.5.1.3.2 Stratigraphy The stratigraphy applicable to the Savannah River basin area is summarized in table 2.5-1.
Igneous and metamorphic rocks varying in age from Precambrian to Paleozoic form the lowest unit believed to be present at the site.
I This material was not encountered during drilling or indicated by the deep refraction seismic work, but is known to form the l
true basement material by direct or inferred means throughout the Georgia-South Carolina area.
i l
2.5-3a 7/27/73 Amendment 5 h
VNP 6
f Table 2.5-1 a
STRATIGRAPHIC -UNITS IN THE VICINITY OF THE ALVIN W. V0GTLE NUCLEAR PLANT SITE System Series Formation Description Recent Alluvial fill and terrace deposits in Qutternary to
-Alluvium stream valleys, consisting of. tan to Pleistocene gray sand, clay, silt, and gravel.
NEocene Hawthorn Tan, red, and purple sandy clay,
' Formation interbedded lenses of gravel, and numerous elastic dikes.
Red, brown, yellow, and buff fine to
,g, Barnwell coarse, massive to cross-bedded sand Tartiary ty Formation and sandy clay.
S Eocene Yellow-brown to green, fine to coarse g_
glauconitic quartz sand, interbedded g,
McBean with green, red, yellow, and tan clay, d3 y Formation sandy marl or limestone, and lenses j3 of siliceous limestone.
U Dark-gray to black sandy lignitic B211eved E11enton micaceous clay containing disseed-to be Upper Formation nated crystals of gypsum. Medium Crataceous to dark-gray coarse sand and white kaolin.
Tan, buff,. red, and white cross-bedded Tuscaloosa-micaceous quartzite and arkosic sand Crataceous Upper Formation and gravel, interbedded with red, brown, and purple clay and white kao-lin.
Gray, dark-brown and brick-red sand-Neuark stone, siltstone, graywacke and clay-Triassic Upper Group stone with included sections of fan-glomerate or conglomerate.
Basement Rock Granite, gneiss, chlorite-hornblende, Paleozoic of the and chlorite-tremolice schist, slate, and Carolina Slate and volcanic rocks.
s Precambrian-Belt and Charlotte Belt a fter.Siple in USGS Water Supply Paper 1841 A
2.5-4
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ALVIN W. VOGTLE NUCLEAR PLANT UNITS 1,2,3 & 4 REGIONAL GEOLOGY SOUTH CAPsOLINA ADJACENT TO SITE FIGURE 2.5 3A
"'""/"
7/27/73 Amendment 5 l.-
VNP at least post-Claiborne sediments.
Although the second possibility, seismic activity, is a likely causative force, it also seems probable that the dike itself was formed both by means of infilling, at an equal pace, of overlying material and by the mechanism includeo in hypothesis 3.
So far as is known, there is no material present now in a stratigraphically higher position in the geologic section and similar in composition to the fracture fill that conceivably might have worked down into the fissure as it was being formed.
There is, however, greenish gray clay in the Hawthorne Formation at downdip localities that could have been present in this area in the geologic past and would be a likely source for such filling.
There is also similar clay stratigraphically lower in the geologic section - a fact which suggests that possibly some 3
dikes were injected up through the younger Tertiary rocks.
Conceivably this injection may have been brought about by the failure of underlying beds to support compressional stresses.
Under such conditions the weight of the overlying material would cause a failure in the substructure brought about by ground water solution of the underlying calcareous beds.
When these beds could no longer support the overlying formations, fractures would develop as the superstructure collapsed, and clastic material below would migrate up into the fractures.
Some corroborative evidence for such an origin is indicated by the large number of solution sinks in the vicinity of the dikes, as for example, in the northeastern quarter of the Ellenton quadrangle.
Conversely, dike swarms are indigenous to those areas exhibiting other features of solution and collapse."
The Quarternary appears largely represented by the flood plain deposits and valley fill associated with the rivers and larger streams in the area.
Most of the stratigraphic units occur north of tne Savannah River in South Carolina.
The chief difference is the appearance of much more extensive areas underlain by calcareous facies of the Barnwell formation, as shown in figure 2.5-3A.
l These facies are named the Cooper marl and the Santee limestone t
(Cooke, 1936, p. 40).
The Santee limestone underlies the Cooper marl and appears to be equivalent to the basal part of the Barnwell (Cooke, 1936, p. 72).
The Cooper marl may be the 5
same age as the upper part of the Barnwell, although the top of the Barnwell may not be as young e.s the upper part of the Cooper marl.
l l
Recent investigation by Siple (1967) in Aiken and Barnwell Counties, South Carolina, reveals Miocene Hawthorne outliers occurring a considerable distance landward from the main belt of Hawthorne strata as shown in Cooke's 1936 map, approaching 2.5-7 7/27/73 Amendment 5
}
I
VNP as near as 8 miles to the outcrop of crystalline basement rocks at the fall line near Augusta, Georgia (see figure 2.5-3A).
Similar Hawthorne outliers are also known in Georgia, as is shown in figure 2.5-3.
A comparison of figures 2.5-3 and 2.5-3A, which show the site region geology in Georgia and South Carolina, respectively, demonstrates the general similarity and continuity of geology across the Savannah River.
The Tuscaloosa-McBean contact crosses the Savannah River about 14 miles downstream from 5
Augusta; the McBean Formation crops out along the Savannah River at least as far as the site.
The isolated patch of oligocene strata (Flint River formation) crops out in the same general area on both sides of the Savannah River.
Although the Barnwell Formation is not mapped as a lime at the site locality, the site is nonetheless on the regional strike with limy beds that are believed to be f acies equivalents of the Barnwell Formation, as shown on figure 2.5-3A.
2.5.1.3.3 Structure The major structural trend affecting the Georgia-South Carolina region along the southern portion is the pre-Mesozoic Appalachian system.
Tectonic activity had ceased on this i
system before the ceposition of the Cretaceous sediments in the Savannah River valley area, as is evidenced by the lack of tectonic folcing or documented fault offsets in the sediments.
Faulting, perhaps of major proportions, appears to have occurreu in the basement complex during the pre-Cretaceous, however, to account for the down-warped or down-f aulted segments of Triassic sediments found preserved within the basement complex throughout much. of the Atlantic Coastal Plain.
The coastal plain sediments indicate the Savannah River basin has remained remarkably stable throughout Upper Mesozoic and Cenozoic times.
The areas of gentle warping recorded in the Georgia-South Carolina area appear in the coastal zone near the city of Savannah or along the southern border with Florida and do not extend to the ~ vicinity of the site.
Studies in conjunction with the SRP inoicate that the Savannah River has been migrating from northeast toward the southwest, leaving a series of well-developea terraces, abandoned meanuers, and flow marking on its South Carolina side.
These features, indicative of previous occupation by the river, are missing from the Georgia side throughout tne Burke County area.
The relatively straight bluff along the Georgia side of this area appears related to a facies change in whicn a hard, bluff-forming clay marl has replaced a green gray silty sand found on 2.5-7a 7/27/73 Amendment 5
f l
VNP the SRP.
The southwestward migration of the Savannah River has resulted in the undercutting of the marl, formation of the linear bluff along the Georgia side, and erosion of the marl facies from the adjacent South Carolina bank.
Structural conditions in South Carolina are completely comparable to those in Georgia.
The site is located over the approximate southern limit of a downfaulted Triassic basin, c
L which extends about 30 miles to the northeast, as outlined in figure 2.5-4A.
Tectonic activity associated with the formation of this basin ceased before the deposition of the Cretaceous sediments upon the basin, as is evidenced by the lack of documented fault offsets in the Cretaceous sediments.
If the j
l Triassic sediments be considered part of the basement complex upon which the Cretaceous and Tertiary materials were i
5 deposited, then the surface of the basement as shown by the structure contours given in figure 2.5-4A descends evenly and without discontinuity across the Triassic sediments.
The only post-Cretaceous warping recorded north of the Savannah River is the " Great Carolina Ridge" (Cooke,1936, p.158), the axis of which lies roughly along the North Carolina-South Carolina i
state line.
It is the landward extension of the Cape Fear arch, which formed during the late Eocene time by an arching of the earth's crust.
Only the Cretaceous and Eocene sediments are af fected by this flexure (Cooke, 1936, p. 158), indicating that activity along the arch ended before deposition of tne Miocene blanket of sediments, about 25 million years ago.
2.5.1.3.4 Ground Water Conditions l
The thick sequence of alternating beds of sand, clay, marl, and limestone underlying the Coastal Plain include several areally extensive aquifer systems containing large quantities of ground water, principally under confined conditions.
Water enters the permeable sands and limestones, principally by direct infiltration of precipitation in their outcrop areas, and migrates southeasterly along the beds, following the slight 2
regional dip.
The nearly impermeable, interbedded clays and marls confine the water within the aquifers, and artesian conditions develop.
The occurrence of ground water, and its utilization in the region is discussed in detail in i
subsection 2.4.13.
The principal regional aquifer system that underlies the plant 4
site is - dae permeable sands of the Tuscaloosa formation.
Water is used from tne Tuscaloosa aquifer in a zone approximately 60 miles wide down-dip of the Fall Line.
Eastward, to the coast, the Tuscaloosa aquifer is deep, and ground water supplies are derivec from overlying, younger formations.
7/27/73 Anendment 5 2.5-7b
-i
+.
Table 2A-1.
DRILLING STATISTICS (Continued)
Number and Type Hole Surface U.D.
No.
Incation Deptte Elevation Purpose Type Drilling Samples Taken Remarks:
30 N 1,145,072 85.0*
91.0 Preliminary Standard Pen ASTM None X-ray diffraction E
626,534 Investigation
& Rotary Tri-cone 31 N 1,143,764 210.0' 211.0 Preliminary Standard Pen ASTM None Observe well/X-ray E
625,237 Investigation
& Rotary Tri-Cone diffraction 32 N 1,144,784 210.08 214.0 Preliminary Standard Pen ASTM None Observe well E
623,572 Investigation
& Rotary Tri-Cone 33 N 1,146,834 220.08 238.0 Preliminary Standard Pen ASTM None Observe well/qamma E
624,864 Investigation
& Rotary Tri-Cone loqqed 34 N 1,147,180 115.08 86.0 Preliminary Standard Pen ASTM None Observe well E
624,846 Investigation
& Rotary Tri-Cone 35A 70.08 94.4 Preliminary Standard Pen ASTM None Investigation
& Rotary Tri-Cone BJ M
36B 150.0' 98.4 Preliminary Standard Pen ASTM None Z
Investigation 5 Rotary Tri-Cone 9
37 N 1,145,243 210.08 195.0 Preliminary Standard Pen ASTM None
' Soil solubilit y test /
E 622,690 Investigation
& Rotary Tri-Cone X-ray diffractlon/
Paleo analynis 38 N 1,143,474 270.0' 257 Preliminary Standard Pen ASTM None E
619,772 Investigation
& Rotary Tri-Cone 19 N 1,149,703 90.0*
118 Preliminary Standard Pen. ASTM None X-ray dif fract ion E
622,835 Investigation
& Notary Tri-Cone 40 N 1,143,210 250.08 215 Preliminary Standard Pen ASTM None E
621,759 Investigation
& Rotary Tri-Cone 41 N 1,142,049 120.0*
222.8 Preliminary Standard Pen ASTM None E
628,658 Investigation
& Rotary Tri-Cone 42 N 1,143,392 250.0' 210 Preliminary Standard Pen ASTM None Paleo analysis /
E 623,553 Investigation
& Rotary Tri-cone carbonate solubilit y tert 42A N 1,143,380 150.08 210.6 Ilydrologic Standard Pen ASTM None Observe well - 150' E
623,535 Data
& Rota ry Tri-Cone
VNP 2.5.1.4.2 Stratigraphy The stratigraphic succession of lidhologic units at the site is relatively simple, but designations of formation names are not i
always in agreement because of the complexity of the strata (see location and details of cross sections on figures 2.5-5 H
through 2.5-9.
1 The site stratigraphy is probably best illustrated by the logs of Holes 147 and 136, both of which were cored with nearly 70 percent recovery to a depth of 300 feet below the ground.
surface.
These holes have surface elevations of 209.5 and 226.2, respectively.
Elevations Description Ground surface -
Upper sand stratum:
185 (+)
Beneath a surface veneer of
~
light brown, fine to medium-grained blow sand, the upper unit consists of fine to medium-grained red, silty, subangular sand, uncemented, some local clayey seams.
185 - 178 (+)
Yellow silty to sandy clay,
.t locally pure, as-in Hole
~
136, but more often found as a clayey sand or sand with thin clay layers.
This marks the contact between the red sands above and the yellow, clayey and I
often calcareous, sands below.
178 - 141 (+)
Yellow to tan, fine to
~
medium-grained silty to clayey sands with occasional clay lenses.
Calcareous material in the form of shell fragments or i
occasional shells are common in this interval i
locally.
141 - 135 (+)
Shell zone: The material in
~
this zone varies from a l
hard calcareously cemented sandstone, to a coquina in 1
l 2.5-8 l
l
d Table 2A-1 DRILLING-STATISTICS (Continued)
_.._,_... Number and Type not.
Surface v.D.
No.
location
_. _. _ _ _ _ _. _ _ -Depth Elevation Purpose Type Drilling Samples Taken Remarks:
102A Adjacent to 177.0' 211.5 Float Standard Pen ASTM Denison-15 102 Foundation Denelon & Rotary Tri-Cone 103 N 1,142,796 100.0' 212.4 Plant Standard Pen ASTM iions E
623,927 Foundation 104 N 1,143,184 100.0' 217.1 Plant Standard Pen ASTM None E
623,398 Foundation
& Rotary N>
m emW 4\\w 4\\
4 La U
(D D
O-
'3 en D
tt i
LTI
Table 2A-1 w
D DRILLING STATISTICS (Continued) w N
~
Nanber and Type j
Note Surface u.u.
No.
Iscation Depth Elevation Purpose Type Drilling Samplee Taken Demarkss Q
5 425 N 1,143,306 1 30.0' 210.4 Mydrologic Standard Pen ASTM None Gasosa logged / observe U
E 623,544 Data
& potary Tri-Cone well - 130' b
42C N 1,143,390 90.0' 210 Nydrologic Standard Pen ASTM None Gamma logged / observe p
E 623,563 Data
& Rotary Tri-Cone well - 90' tt 42D N 1,143,403 70.0' 209.7 Mydrologic Standard Pen ASTM None Observe well - 70' E
623,571 Data
,& Rotary Tri-Cone 42E N 1,143,408 55.0' 209.6 Nydrologic Standard Pen ASTM None Observe well - 55' E
623,500 Data
& notary Tri-cone 43 N 1,144,314 55.0' 282.9 Preliminary Standard Pen ASTM None E
621,810 Investigation
& Rotary Tri-Come tJ 38 44 N 1,146,517 90.0' 241.3 Preliminary Standard Pen ASTN None 4
[
E 623,911 Investigation
& notary Tri-Cae g
45 18,300' 370.0' 273.52 Prolininary Standard Pen ASTM None Gasma logged /Paleo NE of 36 Investigation
& Rotary Tri-Cone analysis 101 N 1,142,945 A00.0' 210.0 Plant!
Standard Pen ASTM None E
623,517 Poundation
& notary Tri-cone 1
101A N 1,142,950 100.0' 210.6 U.D. Sagles notary Tri-Cone 3* Denison-16 Observe well to 200' E
623,515 for neactor Denison & Shelby 3* Shelby-12 Poundation l
lola 20' North of 65.0' 210.8 nulk Sample 24' Auger Hone 24-inch diameter 101 (100 lb) bucket auger holes i
drilled adjacent to existing logged holes solely for 5
the purpose of ob-taining bulk soils samples from speci-i fic depths for testing.
102 N 1,142,796 200.0' 211.5 Plant Standard Pen ASTM None E
623,727 Poundation
& Rotary Tri-Cone l
I
Table 2A-1 DRILLING STATISTICS (Continued)
Number and Type Hole Surface U.D.
No.
tocation Depth Elevation Purpose Type Drilling Samples Taken Remarks:
104A Adjacent to 200.0' 217.1 U.D Samples Rotary Tri-Cone, Shelby-5 4104 for Reactor Stan. Pen ASTM, Denison-6 Foundation Shelby & Denison U.D. Samples from 100' to 200' Standard Pen ASTM w/ intermittent Denison Samples 105 N 1,142,996 30 0.0' 209.7 Reactor Standard Pen ASTM None E
623,626 Foundation
& Rotary'Tri-Cone 106 N 1,142,996 150.0' 209.6 Plant Standard Pen ASTM None E
623,726 Foundation
& Rotary Tri-Cone g
3 107 N 1,142,996 300.0' 209.4 Reactor Standard Pen ASTM None Gamma Logged g
4 E
623,876 Foundation
& Rotary Tri-cone 8t t
107A N 1,142,999 300.0' 209.4 U.D. Samples Mtary Tri-Cone Denison-20 i
E 623,891 for Reactor
& Denison Foundation 1078 20' North of 65.0' 209.4 Bulk Sample 24" Auger Hone 24-inch diameter l
107 (100 lb) bucket auger holes 4
drilled adjacent
\\
to existing logged holes solely for 5
g the purpose of ob-2 taining bulk solle q
t.)
samples from speci-fic depthe for
{
testing.
i h
108 N 1,142,99e 100.0' 210.2 Plant Standard Pen ASTM None p.
E 624,026 Foundation
& Rotary Tri-Cone U
O 109 N 1,143,405 200.0' 216.0 Plant Standard Pen ASTM None i
l E
623,357 Foundation
& Rotary Tri-Cone m
110 N 1,143,385 100.0*
213.5 Plant Standard Pen ASTM None E
623,504 Foundation
& Rotary Tri-Cone
Table 2A-1 DRILLING STATISTICS (Continued)
Number and Type Hole Surface U.D.
No.
Incation Depth Elevation Purpose Type Drilling Samples Taken Remarks:
111 N 1,143,256 200.0' 207.2 Turbine Standard Pen ASTM Denison-4 E
623,726 roundation Denison, Shelby &
Shelby-10 Rotary Tri-Cone 111A Adjacent to 142.0' 207.2 Turbine Rotary Tri-Cone 4" Denison-3 111 roundation Denison 112 N 1,143,256 100.0' 204.3 -Turbine Standard Pen ASTM None E
623,876 roundation
& Dotary Tri-Cone u>
8 0
4
-\\
M M\\w Las D
O.
9m D
et Ln
VNP Unconfinea ground water is present near the surf ace in the Coastal Plain in the outcrop, or recharge areas of each aquifer.
Locally, small bocies of percheu water are found where there are lenses of clay or other low permeable materials above the water table, retarding the downwaru movement of infiltrating precipitation.
Development and use of ground water in the area is predominantly by small domestic wells in the shallow, unconfined zones.
Few deep walls or large capacity industrial 2
or municipal wells are present, and only a small percentage of the aquifer capacities is realized.
Wells in aquifers such as the Tuscaloosa are capable of yields of 2000 gpm or more.
Wells will be constructed in the Tuscaloosa aquifer to provide makeup water for cooling.
The amount used will be less than 4000 gpm, which is only a fraction of the aquifer capacity.
Quality of ground water in the region is good to excellent.
It is low in total dissolved solids, and generally suitable for domestic and industrial uses.
2.5.1.4 Site Geology I
2.5.1.4.1 Topography The site is located on rolling hills, carved from an upland at about 300 feet elevation.
Elevations vary' from about 80 feet at the Savannah River to 280 feet on the crest of a knoll above Mathes Pond.
Surface drainage is to the Savannah River which borders the site on the northeast, via a dendritic series of i
creeks and branches that essen'.lally surround the property.
Rainfall is relatively evenly distributed on a monthly basis and, except during heavy storms, rain tends to soak in rather than run off.
Solutioning of underlying calcareous sands and shells has caused local depressions to form, creating areas of internal drainage.
Springs generally emerge at the top of the l
hard clay marl, causing sapping and headward erosion of the overlying sands and clays and formation of amphitheaters and eventually ravines.
Where thick shell deposits are present, l
small-scale cavernous conditions occur along favored l
percolation paths.
The coalescing of the solution depressions i
or collapse of these small subterranean channels on the top of i
l the clay marl result in ravines with small drainage areas and with amphitheaters at the head like that in which Mathes Pond l
1s located.
L I
i 2.5-7c 7/27/73 Anendment 515
..--_m,-__,.
, ~ _ _ _ _, _..,.
. ~. _ _., _ - _ _. _. -. _,
Table 2A-1
' DRILLING STATISTICS (Continued)
Number and Type Hole Surface U.D.
No.
Location Depth Elevation Purpose' Type Drilling
-Samples Taken Remarks:
113 N 1,143,156 200.0' 203.1
-Turbine Standard Pen ASTM None E
624.026 Foundation
& liotary Tri-Cone 114 N 1,143,504 200.0' 212.0 Plant Standard Pen ASTM Denison-4 Carbonate.
E 623,526 Foundation Denison, Shelby E.
Shelby-16 solubility test Rotary Tri-Cone iteA Adjacent to 155.0' 212.0 Plant Standard Pen ASTM 4" Denison-3 114 Foundation DPRSion, Rotary Tri-Cone 115 N 1,143,506 100.0' 208.5 Plant Standard Pen ASTM None E
623,726 Foundation
& Rotary Tri-Cone 116 N 1,143,503 200.0*
208.0 Plant Standard Pen ASTM None Ca rbonate E
623,928 Foundation
& Rotary Tri-Cone solubility test 117 N.1,143,940 100.08 197.8 Intake Tunnel Standard Pen ASTM teone I
E 624,343 Foundation
& Rotary Tri-Cone
't!
co 118 N 1,144,449 100.0' 198.0 Intake Tunnel Standard Pen ASTM None E
624,961 Foundation
& Rotary Tri-Cone 119 N 1,144,966 100.0' 117.76 Intake Tunnel Standard Pen ASTM None E
625,639
& Rotary Tri-Cone 120 N 1,145,310 100.08 86.8 Intake Stru.
Standard Pen ASTM teone E
626,389 Foundation
& Rotary Tri-Cone 121 N 1,145,472 200.0' 88.8 Intake Stru.
Standard Pen ASTM None Observe well to 08' E
626,200 Foundation.
& Rotaay Tri-Cone 122 N 1,145,719 100.0' 111.4 Intake Stru.
Standard Pen ASTM None E
625,884 Foundation
& Rotary Tri-Cone 123 N 1,146,101 200.08 89.3 Intake Stru.
Standard Pen ASTM None E
625,843 Foundation
& Rotary Tri-Cone 124 N.1,141,896 200.0' 260.2 Cooling Tower Standard Pen. ASTM None Observe well to top E
623,527 Foundation
& Rotary Tri-Cone of Marl / Gamma Loqqewt 125 N 1,142,156 100. 0'.
248.1 Cooling Tower Standard Pen ASTM None E
624,027 Foundation
& Rotary Tri-Cone A
- ~ _
c%
- -)
Table 2A-1
?
s DRILLING-STATISTICS (Continuedl Nud er and Type
,,J Hole Surface U.D.
No.
Incation Depth Elevation Purpose Type Drilling Samples Taken Remarks:
.~
126 N 1,142,997 100.0' 241.4 Cooling Tower Standard Pen ASTM None E
625,306 Foundation
& Rotary Tri-Cone
't;,
127 N 1,144,206 100.0*
199.2 Switchyard Standard Pen ASTM None
~ E 623,176 Foundation
& Rotary Tri-Cone 128 N 1,144,206 100.0' 198.0 Switchyard Standard Pen ASTM None E
623,876 Foundation
& Rotary Tri-Cone 129 N 1,143,856 100.0*
215.9 Switchyard Standard Pen ASTM Mone observe well to top
~
e E
623,576 Fourulation
& Rotary Tri-Cone of Marl 130 N 1,142,796 100.G' 209.6 Plant Standard Pen ASTM None E
623,527 Foundation
& Rotary Tri-Cone 131 N 1,14 3,256 100.0' 213.6 Plant Standard Pen ASTM None 4
E 623,576 Foundation
& Rotary Tri-Cone M
132 N 1,144,988 150.08 169.5 Intake Stru.
Standard Pen ASTM None t
M:
E 626,154 Bluff Slope
& Rotary Tri-Cone Z-Stat:111ty 9
133 N 1,145,146 150.0' 155.0 Intake Stru.
Standard Pen ASTM None E
626,089 Foundation
& Rotary Tri-Cone 134 N 1,146,750 200.0' 191.3 Geologic--
Standard Pen ASTM None E
621,024 Fill-in
& Rotary Tri-Cone r
Section Between B16 & B37 135 N 1,143,992 200.0' 200.5 Geologic--
Cored w/NWM None Observe well to 1
E 622,742 Depression Barrel Face -
below Mar 1/ carbonate Investigation discharge bit solubility test 136 N 1,142,996 300.0' 209.5 Geologic--
Cored w/4x5-1/2 Mone Gamma togged /
E 623,849 Center of barrel, F-D bit carbonate Reactor solubility test 137 N 1,144,839 200.0' 230.6 Unit 1 Cored w/NWM None Observe ' well t o t op E
622,117 Geologic barrel, F-D bit of Marl / Gamma Loqq+d/
Depression Carbonate Investigation solubility test i
Table 2A-1 DRILLING STATISTICS (Continued)
Q Number and Type N
Nole Surface U.D.
M No.
IAcation Depth Elevation Purpose Type Drilling Samples Taken
- Remarks:
9 138 N 1,143,000 99.5' 225.2 Reactor rdn Standard Pen ASTM None Observe well to top w
E 622,500 Units 3 & 4
& Rotary Tri-Cone of Marl
.t*
138A N'1,142,966 200.0' 224.9 U.D. Samples Rotary Tri-Cone, 4" Denison-17 3
E 622,509 for Reactor Denison & Shelby 3" Shelt:y-15 Foundation h
139 N 1,142,996 300.0' 210.9 Geologic Nole Cored w/4x5-1/2 None Cassna Logged /
g3 E
623,526 Edge of barrel, F-D Bit Carbonate
- 3 Reactor solubility test et Unit 2 W
140 N 1,142,846 96.0' 222.4 Units 3 & 4 Standard Pen ASTM None Observe well to E
622,702
& Rotary Tri-Cone Marl - 96.0' 141 N 1,142,860 105.0' 230.4 Units 3&4 Standard Pen ASTM None Observe well to E
622,293 6 Rotary Tri-Cone Harl - 105.0' N
142 N 1,14 3,2 8 3 105.0' 231.2 Units 3 6 4 Standard Pen ASTM None Observe well to
(
E 622,262
& Rotary Tri-Cone Marl - 95.0' p
y 143 N 1,143,283 88.5' 224.5 Units 3 & 4 Standard Pen ASTM None Observe well to E
622,738
& Rotary Tri-Cone Marl - 88.5' 144 N 1,145,403 48.5' 103.2 Intake Struc.
Standard Pen ASTM None Observe well to E
626,124 s Rotary Tri-Cone 48.5' 144A N 1,145,406 51.0' 103.9 Intake strue.
Rotary Tri-Cone 3" Denison-14 E
626,133
& Denison 145 N 1,142,792 192.0' 218.7 Geologic - In Cored w/NWM None C===
I4gged/
E 621.063 Depression barrel, F-D Bit Observe well to Marl - 82.0' 146 N 1,142,966 300.0' 209.6 Seismic Shot Rotary Tri-Cone None This hole was drilled E
623,750 Nole with a tri-cone rotary drill bit only and not logged as it was inten-ded for use in cross-5 hole seismic studies.
The hole was located adjacent to carefully cored holes $136 or 0139 (see figure 2.5-10).
Table 2A-1 DRILLING STATISTICS (Continued)
~
misaber and Type note surface u.D.
No.
Location Depth Elevation Purpose Type Drilling Samples Taken memarks:
147 N 1,142,975 300.0' 226.2 Goulogic cored w/4 5-1/2 teone Camens Logged / Observe E
662,471 Investigation barrel, F-D Bit well to 300.0'/
Units 3 6 4 carbonate soleility test let N 1,142,996 300.0' 209.0 Seismic Shot notary Tri-Cone None This hole was drilled E
623,014 Hole with a tri-cone rotary drill bit only and not logged as it was inten-ded for use in cross-5 hole seismic studies.
It was located 4
adjacent to carefully g
cored holes $136 or og M
0139 (see figure 2.5-10).
-s OW
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>U in D
As 3
in D
tt tsa
?
Table 2A-1 DRILLING STATISTICS (Continued)
Number and Type Hole Surface U.D.
No.
Incation Depth Elevation Purpose Type Drilling Samples Taken Remarks:
149 N 1,142,996 300.0' 209.2 Setemic Shot Rotary Tri-Cone None This hole was drilled E
623,779 Hole with a tri-como rotary drill bit only and not logged as it was inten-ded for use in cross-hole seismic studies.
The hole was located adjacent to carefully cored holes $136 or 0139 (see figure 2.5-10).
150 N 1,142,996 170.0*
210.3 Seismic Shot Rotary Tri-Cone None This hole was drilled E
623,556 Hole with a tri-cone rotary drill bit only and not w
3, logged as it was inton-5 I
dod for use in crose-g hole eelemic studies.
The hole was located
'O adjacent to carefully cored holee 0136 or 0139 (see figure 2.5-10).
151 N 1,142,946 300.0' 210.4 Soissio Shot Rotary Tri-Cone None This hole was drilled E
623,849 Hole with a tri-cono rotary drill bit only and not 4
y logged as it was inton-g ded for use in crose-4 y
-4 hole seismic studies.
N The hole was located j
adjacent to carefully cored holes $136 or 0139 (see figure 2.5-10).
152 N 1,133,831 200.0' 152.7 Geologic Hole Cored w/NWM None Paleo analyelo O
E 633,344 to Complete barrel, F-D Eit U
Sect. between h
Plt. Site &
o Criffin p
Landing et 153 N 1,143,000 39.5' 226.2 Determine Rotary Tri-Cone None E
622,128 Depth of Bearing Horizon l
Table 2A-1 DRILLING STATISTICS (Continued)
Number and Type Nole Surface U.D.
No.
Iscation Dept h Elevation Purpose Type Drilling Samplee Taken Resnarke s 154 N 1,142,796 300.0' 209.5 Seismic Shot Rotary Tri-Cone None comune logged E
623,849 Nole 155 N 1,143,332 86.7' 226.0 Determine Rotary Tri-Cone None E
621,470 Depth of tear-j ing Norizon 156 N 1,131,584 260.0' 237.7 Coelogic Cored w/NNH None E
642,340 Hole - Criffin barrel F-D Bit Landing 157 N 1,145,605 104.1' 207.6 Geologic Nole Cored w/NNH None Filled with Cravel E
621,598 barrel F-D Bit to 149.5' for y
Packer Test g
'o 8
158 N 1,143,838 72.0' 213.0 Determine Rotary Tri-Cone None E
622,866 Depth to Bear-
[
ing Norison 159 H 1,143,931 80.2' 222.2 Determine Rotary Tri-Cone None E
622,401 Depth to Bear =
ing Horizon
-J
\\
ta 4N 4
(J m
D On3m D
(t tn N
Table 2A-1 DRILLING STATISTICS (Continued) '
Number and Type liole Surface U.D.
No.
Iocation Ijepth Elevation Purpose Type Drilling Samples Taken Remarks:
160 N 1,144,157 78.0' 213.7 Determine Rotary Tri-Cone Itone E
622,625
, Depth to Bear-ing Horizon 161 N 1,144,102 65.08 201.0 Determine Rotary Tri-Cone leone E
622,899 Depth of Bear-ing Horizon 162 N 1,144,977 90.0' 235.5 Determine Rotary Tri-cone None E
622,318 Depth to Bear-ing Ilorizon 163 N 1,144,748 95.0' 238.6 Determine Rotary Tri-Cone leone E
621,985 Depth to Bear-ing Horizon M
16 4 N 1,145,401 145.0' 103.2 Seismic Shot Rotary Tri-Cone None Gamma Ingged
{
E 626,120 Hole - Intake,
g g
N 165 N 1,145,354 155.08 112.2 Seisaic Shot Rotary Tri-Cone leone E
626,138 Hole - Intake-166 H 1,145,215 185.0' 143.1 Seismic Shot Rotary Tri-Cone None E
626,194 Hole - Intake 167 N 1,145,388 145.0' 104.6 Seismic Shot Rotary Tri-Cone None E
626,087 Hole - Intake 168 N 1,145,375 147.0' 105.8 Seismic Shot Rotary Tri-Cone None E
626,055 Hole - Intake 169 N 1,145,364 147.0' 106.5 Seismic Shot Rotary Tri-Cone None E
626,027 Hole - Intake 170 N 1,142,988 180.0' 228.3 Packer Test Rotary Tri-Cone None Packer Test E
622,440 17 1 N 1,143,420 90.0' 223.1 Deept Seismic Rotary Tri-Cone None E
621,944 Shot Hole 172 N 1,143,452 90.0' 224.1 Deep Seismic Rotary Tri-Cone None E
621,959 Shot llole 4
m
Table 2A-1 DRILLING STATISTICS (Continued)
Number and Type Nole surface U.D.
No.
location Depth Elevation Purpose Type Drilling Samples Taken itemark s 173 N 1,141,664 30.0' 189.6 Deep Seismic notary Tri-Cone None E
626,629 Shot Hole 174 N 1,141,691 09.0' 189,0 Deep Seismic stotary Tri-Cone None E
626,642 Shot Hole 175 N I,143,386 165.0' 233.1 Investigate Standard Pen ASTN None Gamma Logged / Observe E
621,363 Geologic
& Itotary Tri-Cone well Set to 165.0*
Anomaly 176 N 1,142,117 80.0' 196.4 Water notary Tri-Cone None Observe well to 75.0' E
625,423.0'5 Observation well y
177 N 1,143,560 30.0' 213.0 Water Rotary Tri-Cone None Observe well to 80.0' 8
E 624,865 Observation H
well 4
w Z
178 N 1,144,958 93.0' 240.4 Water notary Tri-Cone None Observe well to 91.0' E
622,994 Observation well 179 N 1,144,059 133.0*
274.8 Water notary Tri-Cone None Observe well to E
621,779 Observation 131.0'
(
well PJ q
100 N 1,142,965 162.0' 210.1 Packer Test notary Tri-Cone None Packer Test N
E 623,724 4
W 181 N 1,143,744 200.0' 258.3 Innstigate Standard Pen ASTM Mone Observe Hole 200'/
E 620,833 Geologic s notary Tri-Cone casena Logged pg Anomaly CD D
182 N 1,144,232.0'4 220.0' 260.4 Investigate Standard Pen ASTN None g
E 620,820 Geologic s notary Tri-Cone g
Anomaly 3
rt
Table 2A-1 DRILLING STATISTICS (Continued)
Ntsaber and Type Hale Surfaos U.D.
No.
Location Depth Elevation Purpose Type Drilling Samples Taken mamarks 183 N 1,143,026.0'4 60.0' 210.8 Water notary Tri-cone None Observe well to 60.0' E
623,526 Observation This hole was drilled well only as observation well for the shallow aquifer and was sched-uled on the basis of data fross adjacent logged holes (see figure 2.5-10).
5 184 N 1,142,996 65.0' 209.4 Water notary Tri-cone None observe well to 65.08 E
623,906 Observation This hole was drilled well only as observation 4
M well for the shallow Z
D I
aquifer and was sched-uled on the basis of w"
data from adjacent g,
logged holes (see figure 2.5-10).
4\\
N J
\\w W
Pa to3 CL 3
tu D
rt Ln
T ble 2A-1 DRILLING STATISTICS (Continued)
Number and Type Hole Surface U.D.
No.
Location Depth Elevation Purpose Type Drilling Samples Taken Remarks:
200 N 1,142,860 10d.08 209.0 Aux. Bldg.
Standard Pen ASTM, Shelby-2 E
623,560 Foundation Rotary Tri-Cone, Flight Auger, Shelby 201 N 1,142,860 100.08 211.4 Aux. Bldg.
Rotary Tri-Cone, Shelby-1 E
623,740 Foundation Std. Pen ASTM, Shelby 202 N 1,142,710 155.78 215.5 Emergency Flight Auger, Std.
Shelby-8 E
623,380 Cooling Pen ASTM, Shelby, Denison-8 i
Tower Denison Foundation 203 N 1,142,730 154.8' 210.9 Railroad Plant Rotary Tri-Cone, Shelby-8 E
623,650 Entrance Std. Pen ASTM, Denison-8 Foundation Shelby, Denison 4
w
{
204 N 1,142,710 156.08 212.8 Emergency Rotary Tri-Cone, Shelby Z 9
E 623,910 Cooling Std. Pen ASTM, Denison-8 g
Tower Fdn Shelby, Denison a
205 N 1,143,310 100.08 212.0 Turbine Rotary Tri-Cone, None E
62?,240 Foundation Std. Pen ASTM 206 N 1,143,310 99.5' 204.0 Turbine Rotary Tri-<one, None E
623,900 Foundation Std. Pen ASTM 207 N 1,143,220 100.5' 212.3 Cooling Tower Rotary Tri-Cone, None E
624,560 Foundation Std. Pen ASTM 208 N 1,143,220 90.58 218.1 Cooling Tower Rotary Tri-Cone, None E
625,070 Foundation Std. Pen ASTM 209 N 1,143,220 99.4' 216.2 Cooling Tower Rotary Tri-Cone, Hone E
625,586 Foundation Std. Pen ASTM 210 N 1,142,680 101.0' 216.9 Cooling Tower Rotary Tri-Cone, None E
624,560 Foundation Std. Pen ASTM 211 N 1,142,680 101. 5' 219.0 Cooling Tower Rotary Tri-Cone None E
625,070 Fcundation Std. Pen ASTM.
e
VNP AEC Question 2.23 Provide those boring logs of holes drilled in the proposed plant ar,ea that were not submitted in the PSAR.
For example, the logs for drill holes 101B, 107B, 146, 148, 149, 150, 151, 103, and 184, which are located in the cohtainment buildings locations, were not provided in the PSAR.
5
Response
There are no logs for the subject holes because these holes were drilled for obtaining limited information only for a special purpose as stated in table 2A-1 and therefore no permanent log was intended.
l l
l f
i I
l t
l l
2.23 7/27/73 Ar.endment 5
VNP AEC Ouestion 2.24 Discuss the significance and magnitude of possible subsidence resulting from fluid withdrawal by means of the proposed water wells that will supply normal make-up water and cooling water during emergency-shutdown conditions.
Verify your estimate of 5
the magnitude of subsidence by providing the appropriate analyses.
Res pons e The answer to this question is provided in paragraph 2.4.13.1.3.3E.
7/27/73 Amendment 5 2.24
1 VNP 4
AEC Ouestion 2.25 In order to complete the geologic and tectonic framework for the proposed site, describe and discuss the geology to the north of the Savannah River, using as guidelines the " Seismic and Geologic Siting Criteria" and the " Standard Format and Content of SARs for Noclear Power Plants."
Show in an appropriate figure the extent and locations of the nearby Triassic Basin and clastic dikes mentioned on page 2.5-6.
5 Re spon se The geology to the north of the Savannah River and the extent and location of the nearby Triassic Basin and clastic dikes are discussed in paragraphs 2.5.1.3.1, 2.5.1.3.2, and 2.5.1.3.3, which were included in Amendment 4.
The geologic map covering the area north of the Savannah River and based on existing geologic data is provided in paragraphs 2.5.1.3.1, 2.5.1.3.2, and 2.5.1.3.3, and figure 2.5-3A.
l l
l 2.25 7/27/73 Amendrent 5 l
VNP 4
[
AEC Question 2.26 The Regulatory Position regarding the site foundation j
exploration for the Vogtle Nuclear Plant is as follows:
i In.the Vogtle site exploration program a large number of f
borings were deployed over a large area of investigation.
Although we and our consultants, the Corps of Engineers, agree that the general geologic conditions at the site are basically as described in the PSAR,- we believe.that more specific. details i
of the foundation conditions, pertinent to design, may have been overlooked due to the. wide spacing of the borings covering the critical structure locations.
specifically, some solutioning of the calcareous clay bearing stratum cannot be rule 6. out, because of its heterogeneous interlayering of sand and fractured limestone which could have l
created solution channels, as evidenced. at times by partial or complete loss of drilling fluid in the marl.
i We and our consultants therefore recommend that, for the 5'
containment. buildings locations, additional borings be placed on a minimum grid of 50 feet on centers and that they penetrate
~
at least 40 feet of fresh, unweathered marl stratum.
- Other, less heavy Category I structures should have an average boring spacing of not more than 100 feet on centers, depending upon the reliance that can be placed on geologic interpretation between borings.
An appropriate number of samples should be recovered from these borings and tested to demonstrate the high bearing capacities represented in Table 2.5-2 of the PSAR, the low compressibility characteristics, and that the upper 15' to 20' of the marl can adequately support the heavy structures.
The applicant has assigned the mechanism causing surface depres sions ' (sinkholes) to the erosion of the shell bed above the marl bearing stratum.
The applicant should provide assurance that the control mechanism for creating sinkholes is due to this entirely, and not in part to deep seated leaching and consolidation of the soils below the bearing stratum.
We, therefore, recommend that the applicant correlate in detail the geometry, locations, and amount of depression of the sinkholes with the extent and thickness of the shell bed; and provide a detailed discussion of the geomorphology of the area.
The additional borings recommended above will provide valuable data in this regard, also.
Re spon se The answer to this question will be submitted later.
7/27/73 Amendment 5 2.26
r-4 VNP AEC Question 3.26 specify the allowable value of tangential shear that can be resisted by concrete alone in a prestressed concrete structure and indicate the reinforcement that will be provided to carry the shear in excess of the allowable.
-Response 5
The answer to this question is provided in paragraph 3.8.1.4.5.
3.26 7/27/73 Arendment 5
W: e g,
. 7 97.
VNP.
AEC' Question 3.27-I ubmit a -lis'e of computer programs that will be used in structural and S
x
-seismic analyses Lto. determine stresses and ' deformations' of Seismic Cate-gory.I structures'... Include a brief description'of;each program and the
' extent':of;its application.
3 Response' Refer.to revised appendix 3F-1 for. response to this question.
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e
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y.
==
c.
j :. '
7/6/7'3 ~ Amendment.~ 3 3.27 1,