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i January 25, 1980 Mr. M. O. Rothwell Bechtel Power Corporation
?.0. Box 1000 Ann Arbor, MI 48106 MIDI.AND PROJECT GWO 7020 -
SOII.S RESPONSES TO 50.54(f) QUESTIONS File: 0485.16 UFI: 00234(S), 71*01 Serial: CSC-4763 After discussions in Bethesda, Maryland, with the NRC on January 16, 1980, and the CP/Bechtel discussions in Ann Arbor on January 22, 1980, the fol-lowing areas should be clarified and/or amplified in our responses to the 50.54(f) questions.
1.
J atanzeck should clarify the slide shown in Washington to indicate the y
, jlay the tank foundation was placed and it should be noted that this is V a six month settlement update only.
via an MCAR update or old question response update..This can be accomplished p 2.
a11 edged quarter inch diesel fuel oil tank settlement needs to be crifisi or deleted from wherevar it was supposedly reported to the NRC.
(J. Wanzeck) 3/ S. Afifi, in the respaase to Question 4, should explain that table 4-1
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is a projection (show totals only) and not what the structure can stand.
He will also relocate this table to Question 27.
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o should verify that "to date" settlement plus additional future ettlement will cause no problems to the diesel generator structure in the response to Question 14.
4.
S. Afifi will indicate how we arrived at the half-inch figure for settle-ment caused by vibration of the diesel generator pedestals due to opera-tion of the diesel generators. In response to Question 27, Dr. Woods analysis to include his method of calculation will be utilized.
S' Afifi vill delete the word " clay" from the third line under note on 5.
- table 4-1.
(Renumbered 27-
).
He will also include the total settle-(
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-File: 0445.16 seric1:.CSC-4763 e 4-1 footnote 2 (Renumbered 27- ) - S. Afifi will explain how he settlement of the borated water storage tank is based on measure-6.
I monts of' the Diesel Generator Building settlement here and in the U,
response-to question 31.
The individual best fit curves projecting diesel generator settlement Therefore, no margin for standard deviation on the best fit.We need to amplify the fact 7.
a is appears to_be unconservative.
the-curves assume the surcharge remains and that the worst data poin
-are utilised for total settlement.something on the worst settlement being ment calculations and their affect on the structure and connections
- 8. Afifi will add some discussion to amplify the conservative aspects and a statement,on the piesometer in response to Question 27.
Item B. basis for accuracy.
Our outline of response to question 27 states:will be changed and one sent 8.
The ou We do not appear to be getting the response curacy is conservatism.
a on the borated water storage tanks..It is necessary to show that for S. Afifi will add emphasis
^ ace soil is adequate in more concise terms.
o the acceptable quality of the soil and that filling the tanks is only t
It will be noted that s
ing done to verify the settlement prediction.
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i l practice. We this -is not a soils problem; rather it is more l ke normaalso h h ld somehow 4
not have the problems which could arise if the foundati i
the tank followed by a tear in the tank wall.We:should also state that we d in this~ analysis.
degree of randommess in the soll as was present in the Die
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Building.-
S. Afifi will do more research 4
, ill be able to withstand seismic events.
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on the overload test necessity.
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l response to question' 33 needs to be amplified to incit de the effect bouyancy on the load tests and what effect the lack of water (if any) 9.
Ou Possibly there from site dewatering will have on the tank settlement.
7 will be a retest after dewatering (S. Afifi).
- 10. ' B. Paris will address whether or not there will be any effect on the u l
d mate heat sink pond seal due to site dewatering in response to 24. f. an l
in note why we are using timers instead of float switches in the pumpsThe basis'for t l
response to 24.
c., utilizing Loughney's input.
l i in tion of the gravel pack material will also be addressed by B. Par if i
the response to 24. d. tion on the riser pipes will be shown by B. Paris on th i
f.
Question 24.
all past loads have been S. 1.o, K. Wiedner and T. Johnson will show thettlements of the Category I l
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accounted for in the analysis of the fut The Imc questioned whether 29 structures in response to Question 28 an e in the past was now locked the stress induced by differential sett1 f
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- r. M. O. Rothwell rile: 0485.16 Serial:
CSC-4763 in the structure and additive to future loads, such as, additional settle-ment, seismic, etc. Our response will include some crack investigative depth core drilling and analysis of relief of stress due to identified po itive remedial measures,
- 12. A response on the Q-ducts has to include an analysis as a category one structure.
It was noted that this may not have been used as criteric in 1970, however, in 1976 this was checked per BC-TOP 4.
This will be in-cluded in our response to Question 30.
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- 13. The response for 24. c. will include an analysis for the concrete service I
water pipes in the cooling pond and any other concrete pipes embedded in the class one fill. In the 24. c. response, B. Paris will also note that V
concrete pipes are generally away from critical structures and discuss probability failures.
14./ After considerable discussion, it appears that the NRC is desirous of 1/ having Bechtel's proppsed detailed method of analysis for the seismic
't event (Question 25). Bechtet will provide their normal analysis for new soils conditions under affected category I structures.
(M. Rothwell)
Bechtel plans a lump mass analysis to include an envelope for settlement.
In discussing Question 26, the NRC noted that they are not in a position to adopt new methods or codes at this point in time, however they (on their own) wish to compare the new methods with earlier analysis to estab-lish some level of margin.
S. Lo's analysis will be complete sometime in mid 1980.
- 15. Miscellaneoust A.
Ceneral A review of the response to Question 16-20 of the subject document criterion indicates that the applicant proposes to impose the 3.0 Se of subparagraph NC-3652.3(b) of the ASME B&PVC,Section III and the 5% radial deformation limit of the AWWA. Additional criteria which address buckling of the piping should be imposed since neither of the proposed 2 criteria are based on this failure mode. Additionally, criteria compliance analyses should be based on maximum expected dif-farential settlement over the life of the plant.
B.
Response to Question 16, Page 16-1 (Civil) e response addresses stresses based on representative pipes being profiled, i.e.1 on current local settlements. The response should be modified to include settlements over the life of the plant.
F C.
Response to Question 17. Page 17-1. Paragraph 1 (Riat)
If all Seismic Category I piping is not to be profiled, criteria for selection of piping to be profiled should be documented.
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Re pon,t, Question 17, P g7 17-2, P r gr ph 2 (Riat)
The calculation assumes that the curvature is constant over the length of pipe.
In general, this condition will not be met. Criteria for
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changes in curvature should be addressed.
E.
Response to Question 17, Page 17-3, Paragraph 2 (Riat)
If the settlement stresses are based on current profiles only, the analysis should be extended to include settlements over the life of the plant and effects of change in curvature (See item C).
F.
Response to Question 17 (Riat)
The question regarding measures to be taken to alleviate conditions if settlement stresses approach code allowables or cannot be determined has not been addressed.
G.
Response to Question 18, Page 18-1, Paragraph 2 and 3 (Riat)
It is not clear that most of the anticipated differential settlement will occur by the time of final closurc (Paragranh 2).
Provisions for effects of settlements occuring af ter final closure should be specified. The evaluations of Paragraph 3 addresses this issue partially.
H.
Response to Que' tion 18, Page 18-2, Paragraph 2 and 3 (Riat) s Criteria for assessment of the flexibility of piping to accomodate more than the expected differential settlement should be specified.
I.
Response to Question 19, Pages 19-1 to 19-3 (Civil)
The disposition of. this response will be delayed pending receipt and review of evaluations based on the preload program (See last paragraph on Page 19-3).
J.
Response to Question 20 (Riat)
The first paragraph of the response is acceptable. However, the remainder f the response requires clarification.
T. C. Cooke Project Superintendent TCC/ps
Attachment:
Attendees List CC: CAHunt KWiedner (Bechtel)
BDahr (Bechtel)
CSKeeley SAfifi (Bechtel)
LCurtis (Bechtel)
DBMiller ABoos (Bechtel)
LDavis (Bechtel)
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Attendees 1/16/ 80
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f Organization Name DPM/NRR Darl Hood COE Detroit Dist.
Joe Kubinski Bechtel - Geotech William Paris Jr.
Bechtel - Geotech Jo Wanzeck Bechtel S. S. Afifi Bechtel W. R. Perris Bechtel M. O. Rothwell Bechtel Karl Wiedner Consumers Power Cil Keeley Consumers Power T.13. Cooke NRC-SEB F. Schaufig Consumers Power J. J. Eabritski Bechtel S. Lo Bechtel T. E. Johnson COE NC Division Chicago John F. Horton Army Corps NCD Chicago t
James W. Simpson U.S. Army COE, Detroit i
William Lawhead NRC-SEB R. E. Lipinski NRC Region III:IE Gene Callagher NRC Region III:IE Ross Landsman NRC NMSS I
Daniel M. Gillen A. J. Cappucci NRC/ DSS /MEB R. O. Busnak NRC/ DSS /HZB H. L. Brarmer NRC/DSE/KMB Ray Gonzales NRC/ DSS f
J. P. Knight NRC/ DSS /GSB I
R. E. Jackson NRC/NRR/0AB l
J. C. Spraul NRC/IE/RCI R.'E. Shewmaker 1/22/80 Bechtel M. Rothve11 Bechtel S. Afifi Bechtel J. Wanzeck Bechtel B. Paris Bechtel Consumers Power Company l
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POW 8r sussect MIDLAND PROJECT GWO 7020 PRE-MEETING WITH CONSULTANTS File B3.0.3 Serial: CSC-4274 UFI#-00234-S.
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Attendees:
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Karl Wiedner, Bechtel Power g,; pg, / i'd 2 Phil Martinez, Bechtel Power Sherif Afif1, Bechtel Power ill 4
Dr. Ralph Peck, Consultant Dr. A. Hendron, Jr., Consultant
?,.~09 M Dr. M. T. Davisson, Consultant
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]Q Tom Cooke, Consumers Power Company
. _ui There was a brief discussion on the various options. One of the main reasons for Option Five (Areal Dewatering) was that it grew. to a large extent out of the dewatering process for Option One. The consultants expressed the opinion that we had to answer liquefaction questions wherever anyone might think they could occur (for example, the control tower at 6KSF loading). It could be a-real thorn in the job at a later date, andareal dewatering is the only clean method. It is very hard to argue against dewatering, and it would be very difficult to prove the effectiveness of grouting. The question was asked about the wa:er that could be trapped in clay. Ihe consultants responced that over the long haul, it would drain with permanent drainage and could be proven by piezometers. While peripheral walls would probably do the job, there would be soms intermediate walls. Any vain of water would be drained.
Piezometers would convincingly prove that the area was dry.. The construction dewatering process for the Amif f ary Building electrical penetration areas will assist in determining how much dewatering and how many wells, etc., are required.
P. Martines indicated that Bechtel would have to take another look at the design calculations in the foundation areas.
The Auxiliary Building electrical penetration area is a high narrow structure with a torsion box at the lower portion. The soil was designed to take the hori-zontal shear. The low soil blow counts values indicate that this structure is possibly being ' cantilevered to some extent off of the control tower. Dr. Peck axpressed the need for the design basis for this structure.
Dr. Hendron indicated that the borings were not necessarily indicative of what was beneath the structure.
A parametric study for the structure should be made based on a range of soil prop-parties. A quick rough analysis should first be done, followed by a detailed analysis. Karl Wiedner discussed the possible outer end settlement and his theory on how the structure had possibly picked up a cantilevered load during construction phases.
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tie Midland Project CWO 7020 - Pre-Meeting with Consultants File: B3.0.3 Serial: CSC-4274 UFIl-00234 August 6, 1979 Tom Davisson then mentioned that, since we were thinking of permanent dewatering a different underpinning method may be acceptable (one that would take vertical loads only).
The Auxiliary Building control tower and the material below the electrical penetration areas have potential for horizontal shear resistance.
three options would be tot The (1) do nothing, (2) supply something for vertical loads only, and (3) supply something for vertical loads and horizontal shear.
The first step would be to check the horizontal shear resistance required.
Possibly horizontal support could be picked up from the Reactor Building and/or Turbine Building.
electrical penetration areas we still would have to analyze for an aid span. Caissons were mentioned as another option.
with an average blow count of three would have modest shear strength.It was noted tha sultants noted that they did not have sufficient desigu information.
The con-basis at the time of this meeting.and other Bechtel personnel present did no Karl Wiedner However, at T. C. Cooke's suggestion, the con-sultants agreed to formulate their quastions in writing for Bechtel response.
The consultants noted that in their opinion, $3 Million for the underpinning of the Auxiliary Building electrical penetration areas was very low, especially when compared to the estimate, of $20 Million for permanent dewatering.
They also stated that we definita1y have a diesel-generator liquefaction problem although the sand would probably never actually liquefy during an earthquake.
The problem was the difficulty in providing calculations which verify this and would not be subject to argument.
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A brief discussion ~ then followed concerning possible liquefaction regarding util-icies, sand backfill around buildings, tank farm, railroad bay and control tower, For the tank farm, railroad bay and control tower, a safety factor of 1.5 etc.
is generally acceptable.
However, if for any reason, the acceleration criteria goes up in the futura Dr. Pack felt that it may be difficult to prove no lique-faction problems.
of proving beyond a shadow of a doubt that everything was satisfacto needicssly conservative decisions may be formulat'ed on the "what if" type questions.
The consultants noted that they were still in favor of a general dewatering program, especially in light of possibly more stringent seismic requirements in the future and the knowledge now available to the effect that generally speaking sand exists in more areas than originally anticipated in the power block area.
The consultants believed that the permanent dewatering program, in general, was a must.
The temporary dewatering system would show how the permanent system would work.
The water can be lowered sufficiently to make the site acceptable in the new licensing Washington to discuss the situation with the NRC.Dr. Peck stated that he could a arena.
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August 15, 1979 TELECOPY BLC-8021
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i Mr. G.S. Kaaley i
f Project Manager CONSUMERS POWER COMPANY 1945 W. Parnall Road Jackson, Michigan 49201 Midland Units 1 and 2
Subject:
Consumers Power Company Bechtel Job ',220 DIESEL GENERATOR BUILDING REMOVAL OF SURCHARGE File: 0614/2801
References:
1)
BLC-680'. dated 11/16/78, P. Martinez to'G. Keeley 2)
Meeting Notes of Consultants Meeting on 5/10/79 3)
Meeting Notes of Consultants Meeting on 6/18 and 6/19/79 4)
Meeting Notes of Consultants Meeting on 6/28/79, Denver, Colo.
5)
Summary of Presen-tat' ion to NRC dated 8/10/79 6)
BEBC-3176 (teletype) dated 8/13/79 R.L. Castleberry to 1
J.F. Newgen I
Daar Mr. Keeley:
The purpose of this letter is to advise you that the intent of the d
proload program has been achieved, and the surcharge can now be we advised you in a letter (Reference 1) of our On November 16, 1978,
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AUG161979 140 LAND PROF' MANACEMENT l
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Bechtel Powar corporauun
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August 15, 197.9 TELT. COPY CONh'AtERS POW.R COMPANY BLC-8021 i
Page 2 intent to carry out our consultants' reconunendation to preload the The placement of 9
diesel generator building and equipment foundations.
ltd surcharge inside and around the diesel generator building was comp e e The surcharge consisted of sand as shown in Drawing 10, 1979.
in April 1979.
7220-C-1141 issued for construction on January
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10, 1979 (Reference 2,
During the meeting with the consultants on May It was recommended the surcharge depth of 20 feet was considered adequate.
by the consultants that the surcharge be maintained at that level ttlement.
approximately 6 additional weeks to allow prediction of long-term se d
In the first part of June 1979, additional instrumentation was installe b
d During a to obtain precise settlement data and measurement of re oun.the mid-June meeting (Reference 3), the consultants concluded that on basis of available data at that time, prediction of future settlement i
be could not be made, and it was requested that the settlemnt read ngs continued to improve the data base.
ldd During a late June 1979 meeting (Reference 4), the consultants conc u that the surcharge could be removed in August, prov have been made.
trend continued af ter proper temperature corrections f Goldberg-The temperature correction devices were developed by the staff oT ion has been summarized by R.B. Peck, one of the consultants at the p Zoino-Dunnicliff & Associates.
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to the NRC on July 18, 1979, as follows (Reference 5.
"The results of the preload procedure have been The observed pore pressures were convincing.
smaller than actually anticipated, and theyHence, primary cons dissipated rapidly.
was accomplished quickly, and the curve of settlement as a function of the logarithm of time became linear shortly after the completion Therefore, it is of placement of the fill.
possible to forecast the settlement that would occur at any future time by simple extra-polation, on the assumption that the surcharge E"en this amount of will remain in place.
However, the settlement would be acceptable.
projected settlement determined on this basis is an upper bound because the surcharge will be removed, and the real sectiements will,
certainly be smaller. "
It was R.B. Peck's judgment t!)at foregoing circumstances eliminate l generator uncertaintics concerning the sectiement behavior of the diosa building resulting from the undcrlying c. lay fill.
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CONatlMERS POWgR COMPANY BLC-8021-Page 3 On August 2,1979, consultants R.B. Peck and A.J. Hendron, Jr. were provided with the latest precise settlement data and calculations for establishing residual settlement.
On August 10 and 13, 1979, A.J. Hendron concurred, in a telephone conversation, with Bechtel's findings that the rate of settlement has decreased to such an extent that for the last 6 weeks there has been essentially no settlement, and that sufficient data have been obtained to allow prediction of long-term settlement by extrapolating the available settlement data. Calculations based on l
present data indicate that the residual settlement over a period of
'40 years due to secondary consolidation of clay will be less than 1 inch.
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A copy of this confirmation letter from the consultants will be provided 1
as soon as it is received.
Because of the favorable settlement character-istics of the surcharge, the design intent of the PSAR in regard to prediction of long-term settlement has been met.
In conclusion, the preload operation has been successfully completad.
The acceptance criteria have been met by providing a reliable residual settlement prediction. Structures, components, and utilities will be designed to accommodate the long-term settlement.
e Removal of surcharge will commence on August 15, 1979. Construction has been ir st;ructed accordingly (Reference 6).
Very truly'yours,
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P.A. Martines Project Manager i
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4 T.J. Sullivan B.W.' Margus11o W. Bird i
T.C. Cooke I
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SUGG U TIONS ON BULK INSTALLATION ACTIVITIES -
$',c"UI..cc FILE Ok60 UFI 73* SERIAL 7594 cc SIUfovell, P-26-3363 DBMiller, Midland (3)
TCCooke, Midland Since March, Project persennel have informally discussed with you some sur;-
gestions which we feal c:ay be pertinent to assure a continuing quality effort on the l'idland Pmject. Attached to this memo are recommendations which we fael you should evaluate for possible implementatio's on the remaining vork on the Midland Project. Some of these items were previously discussed with you. -
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There have been several problem areas associated with the Diesal Generator
, Settlement and as our consultant, Dr Peck, noted we may never be able to determine any one principal reason for the incompletely consolidated material which caused the settlement. In spite of this, it is the opinion of CP Co i
Plc Field personnel that there any be one underlying cause for our problem.
Moisture content. supervision in the field, settlement data, testing, spec interpretation, all seem to center around a certain period of time when the Job was going up and down due to cash flow problems, and when the majority of the earthwork was complete. The single thread that seems to tie all of the known possible causes together is that during the above-mentioned period of
' time there could have been insufficient attention to detail of certain activi-ties during plant fill. People were leaving the site or arriving at the site, t,he aujority of the eacLavurk was done, everyone vmu. Lousing a6 Lhe obr 4=r probless or other work areas or activities that were coming up in the future and that is where the majority of emphasis was placed by all parties. It ap-Pears that people had other work activities in the civil area that.kept them more occupied at that point in time. We are remedying the situation and taking corrective action with respect to effectively checking our quality a's we so to make sure that we do not have a siallar problem so far as future earthwork activities. However, we should not overlook the ' fact that the same thing could happen as other bulk insta11ation activities tail-off. Therefore, as a possible i
suggestion to preclude repetition, we suggest the following 1.
List all areas of bulk installations and their scheduled completion.
2.
Determine which areas may be a prime candidate for problems similar to that which we found with the Diesel Generator Settlement.
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The present concrete act.ivities could be in this category, especially since the bulk of the concrete placement is complete and now we have only small isolated pours remaining.
3.
Assure that personnel pen ming the activities during bulk installation and when tailing off are adequately qualified (construction workers, supervision, technical support and quality personnal).
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Develop specific programs to assure ourselves that as bulk installation progr'ans tail-off, attention to detail will not relax.
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MI** AND SOILS CHRONOLOGY AND S'2tEY Soils placement on the Midland job is broken down between cooling pond cike construction and plant fill. A subcontractor (Canonie, Inc.) constructed the dikes durin; the period of 1969-70 anc 1973-77 Plant area fill (which is essentially cceplete) has been placed by both a subcontractor (Canonie Inc.) and Bechtel. Canonie's work was limited to placement of large, open plant fill areas with mechanical equipment, while Bechtel genera'.ly placed smalle:
areas inaccesible to mechani:ed equipment with hand compactors. Bechtel has, however, placec some areas of plant fill with mechanized equipment. Placement of plant fill has extended from 1974 to present.
All soils testing on the project is performed by a subcontractor (U.S. Testing, Inc.).
Their responsibilities include taking tests in accordance with ASTM standards at locations specified by Bechtel or Canonie. While not explicitly stated in their contract, U.S. Testing has also accepted the job of soils classification to facilitate testing.
Soils placement by Bechtel has been done under the technical direction of Bechtel field engineers assigned to specific plant areas i.e. yard facilities, Auxiliary Building, etc.
There was not a designated soils field engineer on the jobsite. Because they were assigned responsibilities in addition to soils placement (i.e. rebar and formwork inspection, material requisitioning, etc.) the field engineers were not always physically present during the fill placement. Labor foremen were utilized to help call for soils tests under the direction of the field engineer. Technical acceptance of plant fill has been base'd on satisfactory test results.
Bechtel Construction Quality Control performed surveillance over the work done by Canonie. Canonie implemented their own approved QA program and Bechtel QC verified proper im=
plementation by observation and review of records. Two to three times a day Bechtel QC would observe fill placed by Bechtel construction. Full time inspection was not required.
The settlement of the Diesel Generator Building was noted during routine construction survey work.
Settlement markers were assigned and an extensive boring program was endertaken to ascertain the extent of the problem. The results of the boring program which are included in MCAR 24 show material with highly variable in place properties in the first 15 feet under the structure. This fill which includes both clay and sand was placed by Bechtel during 1977.
As a result of the problems noted with the Diesel Generator Building an extensive settle-ment monitoring and soils boring program was undertaken for the balance of the plant. This program, which is still underway, includes borings taken through building base slabs. Those structures / facilities which are or may be effected by soil not meeting specification require-ments to date include:
- 1) Diesel Generator Building
- 2) Unic #1 Main Transformer Area
- 3) Condensate Tank Area
- 4) Service Water Structure (North corner)
- 5) Unit #1 Penetration Room
- 6) Units #1 and #2 Feedwater Isolation Valve Pits
- 7) Borated Water Tank (Western tank only)
As a general rule we note that the " soft" soil encountered under these structures /
facilities was placed by Bechtel using hand held equipment.
A surcharging program is currently underway to preconsolidate the fill under the Diesel Generator Building. Remedial measures to correct soils problems with the other above listed structures / facilities are under investigation.
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